Title of Invention	A THERMALLY STABLE MINERAL WOOL AND A PROCESS FOR PREPARING THE SAME
Abstract	The invention relates to thermally stable mineral wool which can dissolve in a physiological medium, comprising fibres containing the following constituents, expressed in percentage by weight, namely : 35-60% SiO2, preferably 39.55%, 12-27% AI2O3, preferably 16-25%; 0.35% CaO, preferably 3-25% CaO, preferably 3-25%,; 0-30% MgO, preferably 0-15%, 0-17% Na2O, preferably 6-12%, 0-17% K2O, preferably 3-12%, 10-17% R2O(Na2O + K2O), preferably 12-17%;0-5%P2O5, preferably 0-2%;0-20%Fe2O3; )-8%B2O3, preferably 0-4%, and 0.3% TiO2, and at least one phosphorous compound that can react with said fibres at a temperature of less than 1000oC in order to form a coating on the surface thereof. The invention is characterised in that the phosphrous content of said compound, as expressed in phosphorus atom weight, varies between 0.0005%, in particular more than 0.01%, and 1%, in particular less than 0.5%, of the total weight of the fibres. The invention is also characterised in that a phosphorus compound is a molecule in which the phosphorus atom(s) are bound to at least one carbon atom either directly or by means of an oxygen atom.

Title of Invention

A THERMALLY STABLE MINERAL WOOL AND A PROCESS FOR PREPARING THE SAME

Abstract

The invention relates to thermally stable mineral wool which can dissolve in a physiological medium, comprising fibres containing the following constituents, expressed in percentage by weight, namely : 35-60% SiO2, preferably 39.55%, 12-27% AI2O3, preferably 16-25%; 0.35% CaO, preferably 3-25% CaO, preferably 3-25%,; 0-30% MgO, preferably 0-15%, 0-17% Na2O, preferably 6-12%, 0-17% K2O, preferably 3-12%, 10-17% R2O(Na2O + K2O), preferably 12-17%;0-5%P2O5, preferably 0-2%;0-20%Fe2O3; )-8%B2O3, preferably 0-4%, and 0.3% TiO2, and at least one phosphorous compound that can react with said fibres at a temperature of less than 1000oC in order to form a coating on the surface thereof. The invention is characterised in that the phosphrous content of said compound, as expressed in phosphorus atom weight, varies between 0.0005%, in particular more than 0.01%, and 1%, in particular less than 0.5%, of the total weight of the fibres. The invention is also characterised in that a phosphorus compound is a molecule in which the phosphorus atom(s) are bound to at least one carbon atom either directly or by means of an oxygen atom.

Full Text	WO 2006/103375 PCT/FR2006/050280 - 1 - For information purposes only MINERAL WOOL, INSULATING PRODUCT AND PRODUCTION METHOD The present invention relates to the field of artificial mineral wools. It relates more particularly to mineral wools intended for manufacturing thermal and/or acoustic insulation materials or soilless cultivation substrates, and especially to thermally stable mineral wools intended for applications in which temperature resistance is important. These mineral wools are capable of playing an important role in the fire resistance of structural systems into which they are incorporated. The invention relates more particularly to mineral wools of the rock wool type, that is to say those in which the chemical compositions involve a high liquidus temperature and great fluidity at their fiberizing temperature, combined with a high glass transition temperature. Conventionally, this type of mineral wool is fiberized by what are termed "external" centrifugal processes, for example of the type of those using a cascade of spinning wheels supplied with molten material by a static delivery device, as described for example in Patent EP-0 465 310 or Patent EP-0 439 385. The fiberizing process termed "internal" centrifugal process, that is to say one making use of spinners rotating at high speed and pierced by orifices, is, in contrast, conventionally reserved for fiberizing mineral wool of the glass wool type, having broadly a composition relatively rich in alkali metal oxides and a low alumina content, a lower liquidus temperature, - 2 - the viscosity of the wool at the liquidus temperature being higher than that of rock wool or basalt wool. This process is described for example in Patent EP-0 189 354 or Patent EP-0 519 797. However, technical solutions allowing the internal centrifugal process to be adapted to the fiberizing of rock wool have recently been developed, especially by modifying the composition of the constituent material of the spinners and of their operating parameters. For more details on this subject, the reader may refer especially to patent WO 93/02977. Such adaptation consequently makes it possible to combine properties that hitherto have only been inherent to one or other of the two types of wool, namely rock wool or glass wool. Thus the rock wool obtained by an internal centrifugal process is of a quality comparable to that of glass wool, with a lower content of unfiberized particles than in conventionally obtained rock wool. However, it retains the two key advantages associated with its chemical nature, namely a low chemical material cost and a high temperature resistance. Two approaches are therefore now possible for fiberizing rock wool, the choice of one or other depending on a number of criteria, including the required level of quality for the intended application and that of industrial and economic feasibility. Added to these criteria has been, for a few years, that of a biodegradability of the mineral wool, namely its capability of rapidly dissolving in a physiological medium, with a view to preventing any potential pathogenic risk associated with the possible accumulation of the finest fibers in an organism by inhalation. Furthermore, a large number of mineral wool applications use the remarkable thermal stability - 3 - property that certain mineral wool compositions have. In particular, it is known that the thermal stability of mineral wool obtained from iron-enriched slag or basalt is known. The thermal stability of mineral wool is in particular essential for permitting its use in fire-resistant construction systems. One of the key points of fire resistance lies in the capability of the fiber blanket not collapsing (and in thus retaining its thermal insulation properties), this capability stemming from the fact that the fibers undergo no creep or sintering. Patent application WO 01/68546 discloses a mineral wool made thermally stable by the simultaneous use of a particular glass composition and of a phosphorus compound capable of reacting above 100°C with the fibers to form a refractory coating that limits both creep and sintering of the fibers. The phosphorus compounds described in that application are phosphates or polyphosphates, mainly ammonium or sodium phosphates or polyphosphates. These compounds, deposited with the binder on the surface of the fibers, react above 100°C with the surface of the fibers, releasing acid compounds, such as phosphoric acid and/or phosphoric anhydride, which react, depending on the particular chemical composition of the fibers, with the alkaline-earth ions of said fibers to form the above mentioned refractory coating on their surface. It appears that the implementation of the above invention is not without drawbacks in use. The phosphates disclosed in application WO 01/68546 are slightly sensitive, on the one hand, to moisture (when in the polyphosphate state) and, on the other hand, to temperature. The release of acid compounds at relatively low temperature seems to be prejudicial to adhesion between the fibers and the resin-based binder - 4 - (the resin of which is polymerized in an oven at temperatures of about 200°C) , and seems to be the origin of a reduction in the mechanical properties of the end product and above all in the long-term stability of said mechanical properties. It is therefore an object of the present invention to obviate the aforementioned drawbacks by improving the chemical composition of the fibers that mineral wool of the rock wool type contains, so as to give them the capability of being fiberized by the internal centrifugal process, improved mechanical and ageing properties, good thermal stability and good solubility properties in a physiological medium. The subject of the invention is a thermally stable mineral wool capable of dissolving in a physiological medium, which comprises fibers whose constituents are mentioned below, in the following percentages by weight : SiO2 35-60%, preferably 39-55% A12O3 12-27%, 16-25% CaO 0-35%, 3-25% MgO 0-30%, 0-15% Na2O 0-17%, 6-12% K2O 0-17%, 3-12% R20 (Na2O + K2O) 10-17%, 12-17% P2O5 0-5%, 0-2% Fe2O3 0-20%, B2O3 0-8%, 0-4% TiO2 0-3%, and which also includes at least one phosphorus compound capable of reacting at a temperature below 1000°C with said fibers in order to form a coating on the surface of said fibers, said compound having a content, expressed by weight of phosphorus atoms varying from 0.0005%, especially more than 0.01% to 1%, but especially less than 0.5% of the total mass of the fibers, a phosphorus compound being a molecule in which - 5 - the phosphorus atom(s) is (are) linked to at least one carbon atom, directly or via an oxygen atom. Preferably, each phosphorus compound is a molecule in which the phosphorus atom(s) is (are) linked to at least one carbon atom, directly or via an oxygen atom-. Within the context of the present invention, the expression "thermally stable mineral wool" or "mineral wool having a thermal stability" is defined as being capable of exhibiting temperature resistance, that is to say capable of not slumping substantially when it is heated, especially up to temperatures of at least 1000°C. In particular, a mineral wool is considered to be thermally stable if it meets the criteria defined by the draft standard "insulating materials: Thermal stability" as proposed by NORDTEST (NT FIRE XX-NORDTEST REMISS No. 1114-93). This test defines a procedure for determining the thermal stability of a specimen of insulating material at a temperature of 1000°C. A specimen of insulating material (measuring especially 25 mm in height by 25 mm in diameter) is introduced into a furnace but allows the slump of the specimen to be observed as a function of the temperature to which the specimen is exposed. The temperature of the furnace is increased at 5°C per minute from room temperature up to at least 1000°C. This draft standard defines an insulating material as being thermally stable if a specimen of this material slumps no more than 50% of its initial thickness before a temperature the 1000°C is reached. The coating formed on the surface of the high- temperature fibers has the remarkable property of being - 6 - refractory and thus retarding the slump of a specimen of fibers of the selected composition, heated to temperatures that may be up to 1000°C. The or each phosphorus compound may be a single molecule, that is to say, may contain' only one phosphorus atom. The phosphorus compound according to the invention may then be characterized in that the single phosphorus atom is directly linked only to oxygen or hydrogen atoms, that is to say, is linked to at least one carbon atom only by means of an oxygen atom. It may be, as an example, a mono-, di- or tri-phosphoric ester, or unsubstituted phosphonic or phosphinic esters, the carbon-based groups of these esters being alkyl, aryl, alkenyl, alkynyl, acyl or hydroxyalkyl compounds, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, 0 or S. It may alternatively be characterized in that the single phosphorus atom is directly linked to at least one carbon atom. It may be at least partially substituted phosphonic or phosphinic esters or acids (that is to say in which at least one of the hydrogen atoms linked to the phosphorus atom is substituted by a carbon-based substituent). The phosphorus compound in this case could equally be a mono-, di- or tri- phosphoric oxide. The various carbon-based groups of these compounds are alkyl, aryl, acyl or hydroxyalkyl compounds, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, 0 or S. The or each phosphorus compound according to the invention is, however, preferably a molecule made up of several identical or different unitary compounds such as described previously, linked together by covalent - 7 - bonds. The phosphorus compound is then preferably an oligomer or polymer molecule, that is to say, that its structure may be represented as repeating constituent units. The number of these constituent units is advantageously between 2 and 100, especially 2 and 50, or even between 2 and 10. In the case of a molecule containing several phosphorus atoms, the key condition, in accordance with which the phosphorus atoms are linked to a carbon atom, must be seen as signifying that the large majority of the phosphorus atoms respect this condition, it being understood that, in a large molecule, the fact that a small fraction of the phosphorus atoms do not meet this condition is unable to substantially change the manner in which the technical problem is solved. It may thus be a compound in which the majority (or even all) of the phosphorus atoms are linked together by an oxygen atom, for example phosphoric or phosphonic polyester-type compounds. It is, however, more advantageous that the majority (or even all) of the phosphorus atoms be linked together via a carbon-based entity. The phosphorus compound then contains preferably a majority of phosphorus atoms linked together by a group comprising at least one carbon atom, this latter which may be linked directly or by means of an oxygen atom to at least one of the phosphorus atoms. Such a preferred compound may be represented according to the general formula (1) below: - 8 - - n is between 1 and 100, preferably between 1 and 50, especially between 2 and 10; and the substituents R1 to R4 are identical or different, predominantly carbon-based entities, preferably of possibly branched alkyl, aryl, acyl or hydroxyalkyl type, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, 0, S or P. It is preferable that at least one of these substituents, especially the substituent R1, contains an oxygen atom linked to the phosphorus atom of the main chain. If two of the substituents contain an oxygen atom linked to the phosphorus atom of the main chain, the phosphorus compound is advantageously a phosphonic polyester-type oligomer or polymer of general formula (2) below: When all the substituents contain an oxygen atom linked to the phosphorus atom of the main chain, another family of preferred phosphorus compounds is made up of phosphoric polyacid- or polyester-type oligomers or polymers of general formula (3) below: For these last two types of compounds: the chain length n is between 1 and 100, preferably between 1 and 50, especially between 2 and 10; -9- - the substituents R2 and R5 to R8 are identical or different, predominantly carbon-based entities, preferably of possibly branched alkyl, aryl, acyl or hydroxyalkyl type, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, 0, S or P. The number of carbon atoms in each substituent is advantageously between 1 and 15, especially between 2 and 10. A. large number of carbon atoms has in fact the disadvantage of generating a large quantity of carbon-based residues at the time of a temperature rise, whereas too small a number of carbon atoms may result in too easy a hydrolysis. The substituents R6 to R8 may also be hydrogen atoms or a neutralizing base for the phosphoric acid. When the chain length n is equal to 1, it is possible that the R5 and R6 groups be linked together covalently, thus forming a cyclic molecule. When n is greater than 1, some R5, R6 or R7 groups may be linked together covalently. A preferred phosphorus compound is thus the product sold under the trademark AMGARD© CT or CU by Rhodia. It is a mixture of two cyclic phosphonic esters of CAS numbers 41203-81-0 and 42595-45-9 respectively. The first one is a phosphonic ester according to the formula (2) with n=l, all the R2 and R7 groups being methyl groups, the R5 and R6 groups being linked together to form a single alkyl group having 6 carbon atoms. The second one is an ester of the same type, with however n=2, all the R2 groups being methyl groups, the two R5 groups being respectively linked to the R6 and R7 groups to form two C6 alkyl groups. The oligomeric or polymeric phosphorus compounds, presented thus far as linear or cyclic chains, may also be crosslinked networks, the various predominantly carbon-based substituents being able to be themselves linked to at least one other phosphorus atom, for example when these substituents are polyols or - 10 - polyacids. The latter compounds may in particular be obtained by esterification or transesterification reactions between acids or esters, that are phosphonic and phosphoric respectively, and polyols (in particular diols), polyacids (in particular diacids) or else epoxy compounds. Within this scope, molasses (a by-product of sugar refining) are a particularly attractive source of polyols or diols due to their low cost. 1; appeared that the phosphorus compounds according to the invention were able to be obtained by reaction between molasses and the phosphoric or phosphonic acids or esters, this reaction which may even be carried out by simultaneously spraying the two products on the fibers. Phosphorus-based starches may also be employes. The mineral wool according to the invention ion may advantageously comprise a mixture of several phosphorus compounds such as described previously. The point that is common to these compounds, which could be termed "organophosphorus compounds", is the presence of carbon-based compounds within the phosphorus chain itself, which seems to bo the origin of the "blocking" of acid compounds, such at phosphoric acid, for temperatures below 200°C and therefore of the stability of these compounds against the effects of temperature and moisture. The phosphorus compound according to the invention is preferably present in an amount greater than or equal to 0.05%, especially 0.1%, and less than or equal to 2%, especially 1%. This quantity corresponds to the mass of phosphorus compounds relative to the total mass of fibers. Considering the mass of phosphorus in there types of compounds, the mass content of phosphorus atoms - 11 - relative to the mass of fibers is advantageously between 0.0005% to 1%, especially greater than or equal to 0.01% and even 0.1% and less than or equal to 0.5%. The observed coating may be continuous on the surface of a fiber and its thickness is especially between 0.01 and 0.05 urn.. Crystallization of a composition close to that of the coating may also be observed locally on the surface of the fibers and may reach thicknesses of around 0.1 to 0.5 m. According to one advantageous embodiment of the invention, the coating that can form on the surface of the mineral wool fibers potentially consists of an alkaline-earth metal phosphate. Coatings are thus obtained in which the composition is close to that of crystals of the alkaline-earth metal orthophosphate or pyrophosphate type, the melting point of which is known to be above 1000°C. Advantageously, the alkaline-earth metal phosphate that can form on the surface of the mineral wool fibers is a lime phosphate. Lime phosphates, especially orthophosphates (Ca3(PO4)2, or pyrophosphate (Ca2P2O7) , are known to be refractory and these compounds have melting points of 1670°C and 1230°C respectively. As described in application WO 01/68546, a cooperative effect is observed between the fibers that form the subject of the selection of the above constituents and the phosphorus compounds. It may be considered that the phosphorus compound releases, at high temperature (but below 1000°C), phosphoric acid and/or phosphoric anhydride, which starts to react with the fibers of the composition according to the invention. In the case of these compositions, the high alkaline metal content - 12 - that they have may act as a compensator for the charge of aluminum, which is also present at high contents. Thus these are compositions in which the atomic mobility of the alkaline-earth metals is greater than that of these elements in other glass compositions. These relatively mobile alkaline-earth metals are then capable of reacting with the phosphoric acid or phosphoric anhydride to form a refractory compound, especially an alkaline-earth metal phosphate, and thus make it possible to ensure that the mineral wools according to the invention exhibit excellent thermal stability. Thermally stable mineral wool capable of being dissolved in a physiological medium is thus obtained. In the rest of the text, the term "composition" will refer to the ranges of the constituents of the fibers of the mineral wool, or of the glass intended to be fiberized in order to produce said fibers. Any percentage of a constituent of the composition must be understood to be a percentage by weight, and the compositions according to the invention may include up to 5%, especially 3%, of compounds considered as unanalyzed impurities, as is known in this kind of composition. According to a variant of the invention, the composition of the mineral wool is as follows: SiO2 • 39-55%, preferably 40-52% A12O3 16-27%, 16-25% CaO 3-35%, 10-25% MgO 0-15%, 0-10% Na2O 0-15%, 6-12% K2O 0-15%, 3-12% R2O (Na2O + K2O) 10-17%, 12-17% P2O5 0-5%, 0-2% Fe2O3 0-15%, B2O3 0-8%, 0-4% - 13 - TiO2 0-3%, MgO being between 0 and 5%, especially between 0 and 2% when R2O13.0%. By selecting such a composition it is possible to combine the whole series of advantages, especially by varying the many complex roles that a number of its specific constituents play. Specifically, it has been found that the combination of a high alumina content, of between 16 and 27%, preferably greater than 17% and/or preferably less than 25%, especially less than 22%, for a sum of network- forming elements, namely silica and alumina, of between 57 and 75%, preferably greater than 60% and/or preferably less than 72%, especially 70%, with a high quantity of alkali metals (R2O: sodium and potassium) between 10 and 17%, with MgO between 0 and 5%, especially between 0 and 2%, when R2O13.0%, makes it possible to obtain glass compositions possessing the remarkable property of being fiberizable within a very wide range of temperatures and imparting biosolubility in acid pH on the fibers obtained. According to embodiments of the invention, the alkali metal content is preferably greater than 12%, especially 13.0% and 13.3%, and/or preferably less than 15%, especially less than 14.5%. This compositional range proves to be particularly beneficial as it has been observed, contrary to received opinion, that the viscosity of the molten glass does not decrease significantly with an increase in alkali metal content. This remarkable effect makes it possible to increase the difference between the temperature corresponding to the viscosity for fiberizing and the liquidus temperature of the phase that crystallizes, and thus to considerably improve the fiberizing conditions and especially makes it possible to fiberize a new family of biosoluble glasses by - 14 - internal centrifugation. According to one embodiment of the invention, the compositions have an iron oxide content of between 0 and 5%, especially greater than 0.5%, and/or less than 3%, especially less than 2.5%. Another embodiment is obtained with compositions that have an iron oxide content of between 5 and 12%, especially between 5 and 8%, thereby making it possible to obtain fire-resistant mineral wool blankets. Advantageously, the compositions according to the invention satisfy the relationship: (Na2O + K2O)/A12O3) > 0.5, preferably (Na2O + K2O) / A12O3) > 0.6, especially (Na2O + K2O) / A12O3) > 0.7, which appears to favor the temperature corresponding to the viscosity for fiberizing higher than the liquidus temperature being obtained. According to a variant of the invention, the compositions according to the invention preferably have a line content of between 10 and 25%, especially greater than 12%, preferably greater than 15%, and/or preferably less than 23%, especially less than 20% and even less than 17%, combined with a magnesia content of between 0 and 5%, preferably with less than 2% magnesia, especially less than 1% magnesia, and/or a magnesia content greater than 0.3%, especially greater than 0.5%. According to another variant, the magnesia content is between 5 and 10% for a line content between 5 and 15%, and preferably between 5 and 10%. By adding P2O5, which is optional, with contents of between 0 and 3%, especially greater than 0.5% and/or less than 2%, makes it possible to increase the biosolubility in neutral pH. Optionally, the composition may also contain boron oxide, which may - 15 - help to improve the thermal properties of the mineral wool, especially by tending to lower its thermal conductivity coefficient in the radiative component and also to increase the biosolubility in neutral pH. It may also include TiO2 in the composition, optionally, for example up to 3%. Other oxides, such as BaO, SrO, MnO, Cr2O3, ZrO2 and SO3 may be present in the composition, with a total content not exceeding 5%, preferably about 3 or 2%, and even 1%. These various oxides may be intentionally added to the composition according to the invention, but in general they are present as inevitable impurities resulting from the batch materials, from the refractory materials in contact with the glass, or from the refining agents employed to reduce the amount of gaseous inclusions in the mass of molten glass. According to one particularly preferred embodiment of the invention, the mineral wool comprises fibers whose constituents are mentioned below, in the following percentages by weight: SiO2 39-55%, preferably 40-52% A12O3 16-27%, 16-26% CaO 6-20%, 8-18% MgO 0-5%, 1-4.9% Na2O 0-15%, 2-12% K2O 0-15%, 2-12% R2O (Na2O + K2O) 10-14.7%, 10-13.5% P2O5 0-3%, especially 0-2% Fe2O3 (total iron) 1.5-15%, 3.2-8% B2O3 0-2%, preferably 0-1% TiO2 0-2%, 0.4-1%. These compositions by themselves have a remarkably improved high-temperature behavior. It would seem that this composition range makes it possible for crystallization seeds to be nucleated at low temperature, these seeds causing the appearance or - 16 - the growth of crystals at a sufficiently low temperature at which the softening or sintering of the material is not yet able to be effective. It may be considered that, by crystallizing components more fusible than the overall glass composition, the viscosity of the residual glass increases and the surface forces involved for sintering are no longer high enough to prevail over the viscous cohesion forces. Preferably, the alumina is present in an amount of 17 to 25.5%, especially 20 to 25%, in particular 21 to 24.5% and especially around 22 to 23 or 24% by weight. Advantageously, good refractoriness may be obtained by adjusting the magnesia content, especially to at least 1.5%, in particular 2%, especially greater than or equal to 2.5% or 3%. A high magnesia content is conducive to a low-temperature crystallizing effect that opposes the lowering of viscosity generally observed at high temperature, and therefore prevents the material from sintering. One advantageous composition selection consists in providing the required minimum amount of magnesia, this being greater the lower the amount of alumina. Thus, when the alumina is present in an amount of at least 22% by weight, the amount of magnesia is preferably at least 1%, advantageously around 1 to 4%, preferably 1 to 2% and in particular 1.2 to 1.6%. The alumina content is preferably limited to 25% in order to preserve a sufficiently low liquidus temperature. When the alumina is present in a lower amount, for example around 17 to 22%, the amount of magnesia is preferably at least 2%, especially around 2 to 5%. The lime is advantageously present at contents of between 9.5 and 20%, preferably between 10 and 18% and - 17 - even more preferably from 11 to 16%. The total amount of lime and magnesia may advantageously be around 14 to 20%, especially 15 to 19%. The total amount of alkaline-earth metal oxides (lime, magnesia, barium oxide and strontium oxide) is preferably between 10 and 20%, especially from 12 to 18%. The amount of silica is advantageously around 35 to 50%, especially 37 to 48% and more particularly 39 to 4 4%, by weight. Depending on the embodiments of the invention, the alkali metal oxide content is preferably less than or equal to 13.2%, or even 13.0%, especially around 10 to 12.5% and in particular 10.2 to 12% or Jess. Sodium oxide and potassium oxide may each be present in an amount of 3 to 9% by weight. Within this range of alkali metal oxide contents, it proves advantageous to choose a ratio of the alkali metal oxide content to alumina content such that the R2O/Al2O3 molar ratio is less than 1, in particular less than 0.9, especially at most 0.8 and in particular at most 0.75. When the molar ratio is greater than 0.9, it is preferable for the magnesia content to be high enough to produce a low-temperature crystallizing effect, for example at least 2%, or at least 2.5%, otherwise excessively low glass transition temperatures would be obtained, with a deleterious effect on the behavior at very high temperature. An R2O/Al2O3 molar ratio of less than 0.9 produces a favorable effect on refractoriness, in particular at - 18 - low temperature, and therefore on the softening point and the sintering temperature. However, within this composition range a sufficiently large difference is maintained between the temperature corresponding to the viscosity for fiberizing and the liquidus temperature of the phase that crystallizes - thus giving good fiberizing conditions. The iron oxide present in the composition has a positive impact on the nucleation of growth of seeds at low temperature, while still limiting the liquidus. However, its amount is preferably limited so as not to adversely affect biosolubility in acid medium. In a preferred embodiment of the invention, the compositions have iron oxide contents of between 2 and 6%, preferably around 3 to 6%. The titanium oxide provides a very noticeable effect on the nucleation at high and low temperature of spinels within the glassy matrix. A content of the order of 1% or less may prove to be advantageous. P2O5 may be used, at contents of between 0 and 3%, especially between 0.1 and 1.2%, to increase the biosolubility at neutral pH. Other oxides, such as BaO, SrO, MnO, Cr2O3 and ZrO2, may be present in the composition, with a maximum total content of 5%, or even 2%, and even 1%. The difference between the temperature corresponding to a viscosity of 102'5 poise (decipascal.second) , denoted by T1og2.5, and the liquidus of the crystallizing phase, denoted by Tliq, is preferably at least 10°C. This difference, Tlog2.5 - Tiiq, defines the "working range" for the compositions of the invention, that is to say the temperature range within which fiberization is possible, most particularly by an internal centrifugal - 19 - process. This difference is preferably at least 20 or 30°C, and even more than 50°C, especially more than 100°C. The compositions according to the invention have high glass transition temperatures, especially above 600°C. Their annealing temperature, denoted by Tannealing, is especially above 600°C. As mentioned above, the mineral wool exhibits a satisfactory level of biosolubility especially at acid pH. It thus has in general a rate of dissolution, especially measured on silica, of at least 30 and preferably at least 40 or 50 ng/cm2 per hour measured at pH 4.5 using a method similar to that described in the NF T 03-410 standard. Another very important advantage of the invention relates to the possibility of using inexpensive batch materials to obtain the composition of these glasses. These compositions may especially result from the melting of rock, for example of the phonolite type, with an alkaline-earth metal carrier, for example limestone or dolomite, if necessary supplemented with iron ore. By this means, a moderate-cost alumina carrier is obtained. This type of composition, with a high alumina content and a high alkali metal oxide content, may advantageously be melted in fired glass furnaces or electric glass furnaces. The subject of the invention is also a process for obtaining mineral wool according to the invention, which includes a step of fiber-forming followed by a step of supplying, especially by spraying or impregnation of a solution, at least one phosphorus compound onto the surface of said fibers. - 20 - The subject of the invention is also a thermal and/or acoustic insulation product comprising at least one mineral wool according to the invention. The invention also relates to the use of the mineral wool described above in fire-resistant structural systems. The expression "fire-resistant structural systems" is understood to mean systems generally comprising assemblies of materials, especially based on mineral wool and metal plates, that can effectively retard the propagation of heat and also provide protection against flames and hot gases and maintain mechanical strength during a fire. Standardized tests define the degree of fire resistance, expressed especially as the time needed for a given temperature to be reached on the opposite side of the structural system that is exposed to a heat flux generated, for example, by the flames of a burner or by an electric furnace. A structural system is considered to exhibit satisfactory fire resistance if it is able in particular to meet the requirements of one of the following tests: fire door test: tests on mineral fiber boards, as defined in the German standard DIN 18 089 - Part 1 (or equivalent); - fire behavior of building materials and elements, as defined in the German standard DIN 4102 (or equivalent). In particular, the standard DIN 4102 - Part 5 is considered for full-scale tests so as to determine the fire resistance class, and/or the standard DIN 4102 - Part 8 for tests on specimens with a small test bed; and normalized test OMI A 754 (18) (or equivalent), which describes the general fire resistance test - 21 - requirements for "marine"-type applications, especially for ship bulkheads. These tests are carried out on large specimens, with 3 m by 3 m furnaces. Mention may be made, for example, of the case of a steel deck on which the required performance in the case of a fire on the insulation side is to meet the thermal insulation criterion for at least 60 minutes. Other details and advantageous features will become apparent from the description below of nonlimiting preferred embodiments. Table 1 below gives the compositions of the fibers, in percentages by weight, of sixty examples. The "impurities" line corresponds to the inevitable impurities resulting from the batch materials, from the refining agents or from the refractory materials in contact with the molten glass, treated globally. Only their total content is indicated, purely by way of indication, as neither their content, in general less than 2%, or even less than 1%, nor their nature affect the way in which the examples according to the invention solve the stated problem. The compositions according to these examples can be fiberized by an internal centrifugal process, especially according to the teaching of the aforementioned Patent WO 93/02977. Their working ranges, defined by the difference T1Og2.5 - Tliq, are largely positive, especially greater than 50°C, or even 100°C and even greater than 150°C. The liquidus temperatures are relatively low, especially not exceeding 1200°C and even 1150°C. The temperatures (Tlog2.5) corresponding to viscosities of 102.5 poise are compatible with the use of - 22 - centrifugal spinners for high-temperature fiberizing, especially under the operating conditions described in Application WO 93/02977. The preferred compositions are in particular those in which T1Og2.5 is less than 1350°C, preferably less than 1300°C. Table 1 also indicates the annealing temperature (expressed in °C) and the rate of dissolution of the fibers at pH 4.5 (expressed in ng/cm2.h). The latter quantity, measured according to the protocol indicated in standard NF T 03-410, is greater than 30 ng/cm2.h. To illustrate the present invention, various phosphorus compounds were added during the fiberizing process, by spraying them, in a zone located after the zone in which the fibers are attenuated from the molten glass and before the zone in which the mineral wool is collected. The term "adjuvants" refers to the compounds added in this spraying zone, which adjuvants may be supplied simultaneously or separately. The composition of example 45 of Table 1 was fiberized by the internal centrifugal process with or without the presence of various phosphorus-based compounds, in order to obtain mineral wool blankets, and the results of mechanical thermo stability tests are given in Table 2. In these tests, the adjuvant comprises a resin-based binder and, in certain examples, a phosphorus compound added to this binder and sprayed at the same time as the latter. The resin-based binders, well-known in the mineral wool field, have the function of giving the fiber blanket the desired mechanical strength. Within the context of the present tests, a standard binder based on a phenol- - 23 - formaldehyde resin and urea has been employed. Other types of sizing composition, in particular those that are formaldehyde-free, may, of course, also be used, alone or in mixtures. They may be for example: - compositions based on an epoxy resin of the glycidyl ether type and a non-volatile amine hardener (described in Application EP-A-0 369 848), which may also comprise an accelerator chosen from imidazoles, imidazolines and mixtures thereof; compositions comprising a carboxylic polyacid and a polyol, preferably combined with a catalyst of the alkali metal salt of a phosphorus-containing organic acid type (described in Application EP-A-0 990 727); compositions comprising one or more compounds incorporating a carboxylic functional group and/or a -hydroxyaikylamide functional group (described in Application WO-A-93/36368); - compositions incorporating either a carboxylic acid and an alkanolamine, or a resin previously synthesized from a carboxylic acid and from an alkanoiamine, and a polymer containing a carboxylic acid group (described in Application EP-A-1 164 163); sizing compositions prepared in two steps consisting in mixing an anhydride and an amine under reactive conditions until the anhydride is substantially dissolved in the amine. and/or has reacted with it, then in adding water and terminating the reaction (described in Application EP-A-1 170 265) ; - compositions containing a resin that comprises the polymer-free reaction product of an amine with a first anhydride and a second anhydride that is different from the first (described in Application EP- A-1 086 932); compositions containing at least one polycarboxylic acid and at least one polyamine; - compositions comprising copolymers of carboxylic acid and of monomers containing alcohol functional groups such as described in Application US 2005/038193; - 24 - and - compositions comprising polyols and polyacids or polyanhydrides such as maleic acid, described for example in Patent WO 2005/87837 or in Application US 6 706 808. These application or patents EP-A-0 369 848, EP-A-0 990 727, WO-A-93/36368, EP-A-1 164 163, EP-A-1 170 265, EP- A-l 086 932, US 2005/038193, WO 2005/87837, US 6 706 808 are incorporated as reference into the present application, along with applications WO 04/007395, WO 2005/044750, WO 2005/121191, WO 04/094714, WO 04/011519, US 2003/224119, US 2003/22 4120. Aminoplast type resins (melamine-formaldehyde or urea- formaldehyde) may also be used within the scope of. the invention. Comparative example A contained no phosphorus compounds and there formed only the resin-based binder as adjuvant. In the case of the other examples, six different phosphorus compounds were employed. The first three were mineral phosphates or polyphosphates quite similar to those described in application WO 01/68546 and were employed in comparative examples B, C and D. These were the following: sodium metaphosphate. Comparative example B contained 0.2% thereof; - a flame retardant with the trade name "EXOLIT AP 4 62" produced by Clariant GmbH. Based on a ammonium polyphosphate and melamine, it is especially used to improve the fire resistance of polymers (polyurethanes, epoxy resins) and has a very low water solubility. Comparative example C contained 0.2% thereof; and - a flame retardant with the brand name "FR CROS 489" sold by Buddenheim (CAS No. 68333-79-9) . This - 25 - product is an ammonium polyphosphate containing 64% phosphorus expressed in P2O5 form. Comparative example D contained 0.2% thereof. The other three phosphorus compounds were "organophosphorus" compounds employed within the context of the present invention. These were the following: - a flame retardant with the trade name "EXOLIT OP 550" produced by Clariant GmbH. Based on a phosphoric polyester type oligomer, it is especially used as an agent for protecting polyurethanes against: fire. Examples E, F and G according to the invention respectively contained 0.3%, 0.5% and 0.7% of it relative to the total mass of fibers; and - a flame retardant with a brand name "EXOLIT OP 560" produced by Clariant GmbH. Based on an oligomer of the phosphonic polyester type, it is employed in particular as an agent for protecting polyurethanes against fire. Example H according to the invention contained 0.5% thereof; and - a flame retardant with the trade name "FYROL PNX" sold by Akzo Nobel, containing 19% of P2O5. It; is a phosphoric polyester type oligomer of formula (3) in which n varies between 2 and 20, R6, R7 and RB are ethyl groups and R5 is an ethylene group (CAS number 184538- 58-7). Example I according to the invention contained 0.8% of it. These three compounds contain phosphorus atoms and carbon-containing entities, in particular of the alkyl type, in their main chain. Among other examples of phosphorus compounds according to the invention are the products BUDIT 341 or 3118F sold by Buddenheim. The mixture of cyclic phosphonic esters sold under the trademark AMGARD© CT or CU by Rhodia is also particularly interesting. This product, used as a fire retardant for polyester-based textiles, - 26 - has in fact a higher stability than the product EXOLIT OP 550 at the temperature of the oven, and thus makes it possible to obtain better mechanical properties before aging. Its P2O5 content is about 20%. Table 2 gives, for all of these tests, the initial mechanical strength of the mineral wool products obtained and the loss of their mechanical strength (as a relative percentage) after ageing in an autoclave at 105°C under a pressure of 1.5 bar for 15 minutes, and for some of these tests the slump at 1000°C, according to the draft standard "insulating materials: thermal stability" mentioned above. The mechanical strength was measured before and after autoclave ageing by tensile tests carried out on specimens in the form of rings cut from the fibrous products with a density of 14 kg/m3. According to this test, two pins were introduced into the center of the ring and moved apart at a constant rate until the specimen broke. This strength, expressed in N/g, corresponds to the force at break divided by the mass of the specimen. The test was repeated on twenty specimens, the average of the results obtained being indicated in the table. - 27 - Table 2 These results clearly show that the addition of phosphorus compounds such as those described in the prior art (examples B, C and D) do not improve the initial mechanical strength properties or degrade them (upon leaving the oven) and also greatly degrade the variation in these properties over time compared with the case in which no phosphorus compound was added (example A). In contrast, the use of the phosphorus compounds within the context of the present invention, on the one hand, improves the initial mechanical properties of the product and, on the other hand, either does not degrade the variation in these properties after accelerated ageing (examples F, H and I) or even improves them (examples E and G) . Without wishing to be tied by any scientific theory, the beneficial effect of adding the compounds according to the invention seems to be due to the absence of acid compounds being liberated, such as phosphoric acid and/or phosphoric anhydride, during the oven treatment for curing the resin of the binder and during the accelerated ageing treatment on the end product. This is because it seems that the liberation of acid compounds causes the adhesion between the binder and - 28 - the glass fibers to be reduced and/or attacks the surface of the fibers. It has also been demonstrated independently of the present invention that the addition of a base (such as MgO) as additional adjuvant makes it possible to neutralize the acids formed during this binder curing step and offers advantages with regard to the variation in mechanical properties over time of the products thus formed. The beneficial effect of all these types of phosphates (comparative example B or examples E and I according to the invention) on the thermal stability is also confirmed, the slump at 1000°C being reduced by at least a factor of two compared with that of fibers without phosphate compounds. WO 2006/103375 PCT/FR2006/050280 - 35 - CLAIMS 1. A thermally stable mineral wool capable of dissolving in a physiological medium, which comprises fibers whose constituents are mentioned below, in the following percentages by weight: SiO2 35-60%, preferably 39-55% A12O3 12-27%, 16-25% CaO 0-35%, 3-25% MgO 0-30%, 0-15% Na2O 0-17%, 6-12% K2O 0-17%, 3-12% R2O (Na2O + K2O) 10-17%, 12-17% P2O5 0-5%, 0-2% Fe2O3 0-20%, B2O3 0-8%, 0-4% TiO2 0-3%, and at least one phosphorus compound capable of reacting at a temperature below 1000°C with said fibers in order to form a coating on the surface of said fibers, said compound characterized in that the content, expressed by weight: of phosphorus atoms varies from 0.0005%, especially more than 0.01% to 1%, but especially less than 0.5% of the total mass of the fibers, and in that a phosphorus compound being a molecule in which the phosphorus atom(s) is (are) linked to at least one carbon atom, directly or via an oxygen atom. 2. The mineral wool as claimed in claim 1, comprising at least one phosphorus compound chosen from: a) a molecule containing a single phosphorus atom linked to at least one carbon atom, strictly by means of an oxygen atom;. b) a molecule containing a single phosphorus atom linked directly to at least one carbon atom. 3. The mineral wool as claimed in the previous claim, comprising at least one phosphorus compound (a) - 3 6 - chosen from: a mono-, di- or tri-phosphoric ester, or an unsubstituted phosphonic or phosphinic ester, the carbon-based groups of these esters being alkyl, aryl, acyl or hydroxyalkyl compounds, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, 0 or S. 4. The mineral wool as claimed in claim 2, comprising at least one phosphorus compound (b) chosen from an at least partially substituted phosphonic or a mono-, di- or tri-phosphinic ester or acid, the various carbon-based groups of these compounds being alkyl, aryl, acyl or hydroxyalkyl compounds, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, 0 or S. b. The mineral wool as claimed in claim 1, comprising at least one phosphorus compound that is a molecule made up of several compounds of type (a) or (b) as claimed in claims 2 to 4, that are identical or different., linked together by covalent bonds. 6. The mineral wool as claimed in the previous claim, comprising at least one phosphorus compound that is an oligomer or polymer molecule, of which the number of constituent units is preferentially between 2 and 100, especially 2 and 50, or even between 2 and 10. 7. The mineral wool as claimed in claim 5 or 6, comprising at least one phosphorus compound that contains predominantly phosphorus atoms linked together via a carbon-based entity. 8. The mineral wool as claimed in the previous claim, comprising at least one phosphorus compound that may be represented according to the genera] formula (1) below: - 37 - in which: - n is between 1 and 100, preferably between 1 and 50, especially between 2 and 10; the substituents R1 to R4 are identical or different, predominantly carbon-based entities, preferably of possibly branched alkyl, aryl, acyl or hydroxyalkyl type, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, O, S or P. 9. The mineral wool as claimed in the previous claim, comprising at least one phosphorus compound that is a phosphonic polyester-type oligomer or polymer of general formula (2) below: in which: - the chain length n is between 1 and 100, preferably between 1 and 50, especially between 2 and 10; and - the substituents R2 and R5 to R7 are identical or different, predominantly carbon-based entities, preferably of possibly branched alkyl, aryl, acyl or hydroxyalkyl type, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, 0, S or P. 10. The mineral wool as claimed in claim 8, comprising at least one phosphorus compound that is a phosphoric polyacid or polyester-type oligomer or polymer of general formula (3) below: in which: the chain length n is between 1 and 100, preferably between 1 and 50, especially between 2 and 10; - the substituents R5 to R8 are identical or different, predominantly carbon-based entities, preferably of possibly branched alkyl, aryl, acyl or hydroxyalkyl type, which may possibly be of oligomeric or polymeric nature and/or contain one or more heteroatoms chosen from N, O, S or P. 11. The mineral wool as claimed in one of claims 4 to 10, comprising at least one phosphorus compound that is obtained by an ester Lfication or transesterification reaction between acids or esters, that are phosphonic and phosphoric respectively, and polyols (in particular diols), polyacids (in particular diacids) or epoxy compounds. 12. The mineral wool as claimed in the previous claim, comprising at least one phosphorus compound that is obtained by reaction between molasses and the phosphoric or phosphonic acids or esters. 13. A mineral wool as claimed in one of the preceding claims, comprising fibers who constituents are mentioned below, the following percentages by weight: SiO2 39-55%, preferably 40-52% A12O3 16-27%, 16-25% CaO 3-35%, 10-25% MgO 0-15%, 0-10% Na2O 0-15%, 6-12% K2O 0-15%, 3-12% R2O (Na-0 -1- K2O) 10-17%, 12-17% p2O3 0-5%, 0-2% - 39 - Fe2O3 0-15%, B2O3 0-8%, 0-4% TiO2 0-3%, MgO being between 0 and 5%, especially between 0 and 2% when R2O13.0%. 14. The mineral wool as claimed in one of the preceding claims, comprising fibers whose constituents are mentioned below, in the following percentages by weight: SiO2 39-55%, preferably 40-52% A12O3 16-27%, 16-26% CaO 6-20%, 8-18% MgO 1-5%, 1-4.9% Na2O 0-15%, .2-12% K2O 0-15%, 2-12% R2O (Na2O + K2O) 10-14.7%, 10-13.5% P2O5 0-3%, especially 0-2% Fe2O3 (Total Iron) 1.5-15%, 3.2-8% B2O3 0-2%, preferably 0-1% TiO2 , 0-2%, 0.4-1%. 15. The mineral wool as claimed in one of the preceding claims, such that the CaO content is between 9.5 and 20%, preferably between 10 and 18%. 16. The mineral wool as claimed in one of the preceding claims, containing 20 to 25% alumina. 17 . A mineral wool as claimed in one of the preceding claims, containing at least 2%, especially around 2 to 5%, MgO when the alumina is present in an amount of less than 22%, especially 17 to 22%, and containing 1 to 4%, preferably 1 to 2%, MgO when the alumina is present in an amount of at least 22% by weight. 18. The mineral wool as claimed in one of the preceding claims, such that the alkaline metal content is preferably less than or equal to 13.0%, especially around 10 to 12.5%, in particular 12% or less. 19. The mineral wool as claimed in one of the preceding claims, such that the R2O/A12O3 molar ratio is - 40 - less than 0.9, especially at most 0.8, in particular at most 0.75. 20. The mineral wool as claimed in one of the preceding claims, containing 2 to 6% iron oxide. 21. The mineral wool as claimed in one of the preceding claims, containing 1% titanium oxide or less. 22. The mineral wool as claimed in one of the preceding claims, such that the fibers have a rate of dissolution of at least 30 ng/cm2 per hour measured at pH 4.5. 23. The mineral wool as claimed in one of the preceding claims, in which the glass corresponding to the fibers may be fiberized by the internal centrifugal process. 24. The mineral wool as claimed in one of the preceding claims, in which the coating that: can be formed on the surface of the fibers essentially consists of an alkaline-earth metal phosphate. 25. The mineral wool as claimed in the preceding claim, in which the alkaline-earth metal phosphate is a lime phosphate. 26. A process for obtaining mineral wool as claimed in one of the preceding claims which includes a step of fiber-forming followed by a step of supplying, especially by spraying or impregnation of a solution, at least one phosphorus compound onto the surface of said fibers. 27. The use of the mineral wool as claimed ;n any one of the preceding mineral wool claims in fire- resistant structural systems. 28. A thermal and/or acoustic insulation product comprising at least one mineral wool as claimed in one of the preceding mineral wool claims. The invention relates to thermally stable mineral wool which can dissolve in a physiological medium, comprising fibres containing the following constituents, expressed in percentage by weight, namely : 35-60% SiO2, preferably 39.55%, 12-27% AI2O3, preferably 16-25%; 0.35% CaO, preferably 3-25% CaO, preferably 3-25%,; 0-30% MgO, preferably 0-15%, 0-17% Na2O, preferably 6-12%, 0-17% K2O, preferably 3-12%, 10-17% R2O(Na2O + K2O), preferably 12-17%;0-5%P2O5, preferably 0-2%;0-20%Fe2O3; )-8%B2O3, preferably 0-4%, and 0.3% TiO2, and at least one phosphorous compound that can react with said fibres at a temperature of less than 1000oC in order to form a coating on the surface thereof. The invention is characterised in that the phosphrous content of said compound, as expressed in phosphorus atom weight, varies between 0.0005%, in particular more than 0.01%, and 1%, in particular less than 0.5%, of the total weight of the fibres. The invention is also characterised in that a phosphorus compound is a molecule in which the phosphorus atom(s) are bound to at least one carbon atom either directly or by means of an oxygen atom.

Full Text

WO 2006/103375 PCT/FR2006/050280
- 1 -
For information purposes only
MINERAL WOOL, INSULATING PRODUCT AND PRODUCTION METHOD
The present invention relates to the field of
artificial mineral wools. It relates more particularly
to mineral wools intended for manufacturing thermal
and/or acoustic insulation materials or soilless
cultivation substrates, and especially to thermally
stable mineral wools intended for applications in which
temperature resistance is important.
These mineral wools are capable of playing an important
role in the fire resistance of structural systems into
which they are incorporated.
The invention relates more particularly to mineral
wools of the rock wool type, that is to say those in
which the chemical compositions involve a high liquidus
temperature and great fluidity at their fiberizing
temperature, combined with a high glass transition
temperature.
Conventionally, this type of mineral wool is fiberized
by what are termed "external" centrifugal processes,
for example of the type of those using a cascade of
spinning wheels supplied with molten material by a
static delivery device, as described for example in
Patent EP-0 465 310 or Patent EP-0 439 385.
The fiberizing process termed "internal" centrifugal
process, that is to say one making use of spinners
rotating at high speed and pierced by orifices, is, in
contrast, conventionally reserved for fiberizing
mineral wool of the glass wool type, having broadly a
composition relatively rich in alkali metal oxides and
a low alumina content, a lower liquidus temperature,

- 2 -
the viscosity of the wool at the liquidus temperature
being higher than that of rock wool or basalt wool.
This process is described for example in Patent
EP-0 189 354 or Patent EP-0 519 797.
However, technical solutions allowing the internal
centrifugal process to be adapted to the fiberizing of
rock wool have recently been developed, especially by
modifying the composition of the constituent material
of the spinners and of their operating parameters. For
more details on this subject, the reader may refer
especially to patent WO 93/02977. Such adaptation
consequently makes it possible to combine properties
that hitherto have only been inherent to one or other
of the two types of wool, namely rock wool or glass
wool. Thus the rock wool obtained by an internal
centrifugal process is of a quality comparable to that
of glass wool, with a lower content of unfiberized
particles than in conventionally obtained rock wool.
However, it retains the two key advantages associated
with its chemical nature, namely a low chemical
material cost and a high temperature resistance.
Two approaches are therefore now possible for
fiberizing rock wool, the choice of one or other
depending on a number of criteria, including the
required level of quality for the intended application
and that of industrial and economic feasibility.
Added to these criteria has been, for a few years, that
of a biodegradability of the mineral wool, namely its
capability of rapidly dissolving in a physiological
medium, with a view to preventing any potential
pathogenic risk associated with the possible
accumulation of the finest fibers in an organism by
inhalation.
Furthermore, a large number of mineral wool
applications use the remarkable thermal stability

- 3 -
property that certain mineral wool compositions have.
In particular, it is known that the thermal stability
of mineral wool obtained from iron-enriched slag or
basalt is known.
The thermal stability of mineral wool is in particular
essential for permitting its use in fire-resistant
construction systems. One of the key points of fire
resistance lies in the capability of the fiber blanket
not collapsing (and in thus retaining its thermal
insulation properties), this capability stemming from
the fact that the fibers undergo no creep or sintering.
Patent application WO 01/68546 discloses a mineral wool
made thermally stable by the simultaneous use of a
particular glass composition and of a phosphorus
compound capable of reacting above 100°C with the
fibers to form a refractory coating that limits both
creep and sintering of the fibers.
The phosphorus compounds described in that application
are phosphates or polyphosphates, mainly ammonium or
sodium phosphates or polyphosphates. These compounds,
deposited with the binder on the surface of the fibers,
react above 100°C with the surface of the fibers,
releasing acid compounds, such as phosphoric acid
and/or phosphoric anhydride, which react, depending on
the particular chemical composition of the fibers, with
the alkaline-earth ions of said fibers to form the
above mentioned refractory coating on their surface.
It appears that the implementation of the above
invention is not without drawbacks in use. The
phosphates disclosed in application WO 01/68546 are
slightly sensitive, on the one hand, to moisture (when
in the polyphosphate state) and, on the other hand, to
temperature. The release of acid compounds at
relatively low temperature seems to be prejudicial to
adhesion between the fibers and the resin-based binder

- 4 -
(the resin of which is polymerized in an oven at
temperatures of about 200°C) , and seems to be the
origin of a reduction in the mechanical properties of
the end product and above all in the long-term
stability of said mechanical properties.
It is therefore an object of the present invention to
obviate the aforementioned drawbacks by improving the
chemical composition of the fibers that mineral wool of
the rock wool type contains, so as to give them the
capability of being fiberized by the internal
centrifugal process, improved mechanical and ageing
properties, good thermal stability and good solubility
properties in a physiological medium.
The subject of the invention is a thermally stable
mineral wool capable of dissolving in a physiological
medium, which comprises fibers whose constituents are
mentioned below, in the following percentages by
weight :
SiO2 35-60%, preferably 39-55%
A12O3 12-27%, 16-25%
CaO 0-35%, 3-25%
MgO 0-30%, 0-15%
Na2O 0-17%, 6-12%
K2O 0-17%, 3-12%
R20 (Na2O + K2O) 10-17%, 12-17%
P2O5 0-5%, 0-2%
Fe2O3 0-20%,
B2O3 0-8%, 0-4%
TiO2 0-3%,
and which also includes at least one phosphorus
compound capable of reacting at a temperature below
1000°C with said fibers in order to form a coating on
the surface of said fibers, said compound having a
content, expressed by weight of phosphorus atoms
varying from 0.0005%, especially more than 0.01% to 1%,
but especially less than 0.5% of the total mass of the
fibers, a phosphorus compound being a molecule in which

- 5 -
the phosphorus atom(s) is (are) linked to at least one
carbon atom, directly or via an oxygen atom.
Preferably, each phosphorus compound is a molecule in
which the phosphorus atom(s) is (are) linked to at
least one carbon atom, directly or via an oxygen atom-.
Within the context of the present invention, the
expression "thermally stable mineral wool" or "mineral
wool having a thermal stability" is defined as being
capable of exhibiting temperature resistance, that is
to say capable of not slumping substantially when it is
heated, especially up to temperatures of at least
1000°C.
In particular, a mineral wool is considered to be
thermally stable if it meets the criteria defined by
the draft standard "insulating materials: Thermal
stability" as proposed by NORDTEST (NT FIRE XX-NORDTEST
REMISS No. 1114-93).
This test defines a procedure for determining the
thermal stability of a specimen of insulating material
at a temperature of 1000°C. A specimen of insulating
material (measuring especially 25 mm in height by 25 mm
in diameter) is introduced into a furnace but allows
the slump of the specimen to be observed as a function
of the temperature to which the specimen is exposed.
The temperature of the furnace is increased at 5°C per
minute from room temperature up to at least 1000°C.
This draft standard defines an insulating material as
being thermally stable if a specimen of this material
slumps no more than 50% of its initial thickness before
a temperature the 1000°C is reached.
The coating formed on the surface of the high-
temperature fibers has the remarkable property of being

- 6 -
refractory and thus retarding the slump of a specimen
of fibers of the selected composition, heated to
temperatures that may be up to 1000°C.
The or each phosphorus compound may be a single
molecule, that is to say, may contain' only one
phosphorus atom.
The phosphorus compound according to the invention may
then be characterized in that the single phosphorus
atom is directly linked only to oxygen or hydrogen
atoms, that is to say, is linked to at least one carbon
atom only by means of an oxygen atom. It may be, as an
example, a mono-, di- or tri-phosphoric ester, or
unsubstituted phosphonic or phosphinic esters, the
carbon-based groups of these esters being alkyl, aryl,
alkenyl, alkynyl, acyl or hydroxyalkyl compounds, which
may possibly be of oligomeric or polymeric nature
and/or contain one or more heteroatoms chosen from N, 0
or S.
It may alternatively be characterized in that the
single phosphorus atom is directly linked to at least
one carbon atom. It may be at least partially
substituted phosphonic or phosphinic esters or acids
(that is to say in which at least one of the hydrogen
atoms linked to the phosphorus atom is substituted by a
carbon-based substituent). The phosphorus compound in
this case could equally be a mono-, di- or tri-
phosphoric oxide. The various carbon-based groups of
these compounds are alkyl, aryl, acyl or hydroxyalkyl
compounds, which may possibly be of oligomeric or
polymeric nature and/or contain one or more heteroatoms
chosen from N, 0 or S.
The or each phosphorus compound according to the
invention is, however, preferably a molecule made up of
several identical or different unitary compounds such
as described previously, linked together by covalent

- 7 -
bonds. The phosphorus compound is then preferably an
oligomer or polymer molecule, that is to say, that its
structure may be represented as repeating constituent
units. The number of these constituent units is
advantageously between 2 and 100, especially 2 and 50,
or even between 2 and 10. In the case of a molecule
containing several phosphorus atoms, the key condition,
in accordance with which the phosphorus atoms are
linked to a carbon atom, must be seen as signifying
that the large majority of the phosphorus atoms respect
this condition, it being understood that, in a large
molecule, the fact that a small fraction of the
phosphorus atoms do not meet this condition is unable
to substantially change the manner in which the
technical problem is solved.
It may thus be a compound in which the majority (or
even all) of the phosphorus atoms are linked together
by an oxygen atom, for example phosphoric or phosphonic
polyester-type compounds.
It is, however, more advantageous that the majority (or
even all) of the phosphorus atoms be linked together
via a carbon-based entity. The phosphorus compound then
contains preferably a majority of phosphorus atoms
linked together by a group comprising at least one
carbon atom, this latter which may be linked directly
or by means of an oxygen atom to at least one of the
phosphorus atoms. Such a preferred compound may be
represented according to the general formula (1) below:

- 8 -
- n is between 1 and 100, preferably between 1 and
50, especially between 2 and 10; and
the substituents R1 to R4 are identical or
different, predominantly carbon-based entities,
preferably of possibly branched alkyl, aryl, acyl or
hydroxyalkyl type, which may possibly be of oligomeric
or polymeric nature and/or contain one or more
heteroatoms chosen from N, 0, S or P. It is preferable
that at least one of these substituents, especially the
substituent R1, contains an oxygen atom linked to the
phosphorus atom of the main chain.
If two of the substituents contain an oxygen atom
linked to the phosphorus atom of the main chain, the
phosphorus compound is advantageously a phosphonic
polyester-type oligomer or polymer of general formula
(2) below:

When all the substituents contain an oxygen atom linked
to the phosphorus atom of the main chain, another
family of preferred phosphorus compounds is made up of
phosphoric polyacid- or polyester-type oligomers or
polymers of general formula (3) below:

For these last two types of compounds:
the chain length n is between 1 and 100,
preferably between 1 and 50, especially between 2 and
10;

-9-
- the substituents R2 and R5 to R8 are identical or
different, predominantly carbon-based entities,
preferably of possibly branched alkyl, aryl, acyl or
hydroxyalkyl type, which may possibly be of oligomeric
or polymeric nature and/or contain one or more
heteroatoms chosen from N, 0, S or P. The number of
carbon atoms in each substituent is advantageously
between 1 and 15, especially between 2 and 10. A. large
number of carbon atoms has in fact the disadvantage of
generating a large quantity of carbon-based residues at
the time of a temperature rise, whereas too small a
number of carbon atoms may result in too easy a
hydrolysis. The substituents R6 to R8 may also be
hydrogen atoms or a neutralizing base for the
phosphoric acid.
When the chain length n is equal to 1, it is possible
that the R5 and R6 groups be linked together covalently,
thus forming a cyclic molecule. When n is greater than
1, some R5, R6 or R7 groups may be linked together
covalently. A preferred phosphorus compound is thus the
product sold under the trademark AMGARD© CT or CU by
Rhodia. It is a mixture of two cyclic phosphonic esters
of CAS numbers 41203-81-0 and 42595-45-9 respectively.
The first one is a phosphonic ester according to the
formula (2) with n=l, all the R2 and R7 groups being
methyl groups, the R5 and R6 groups being linked
together to form a single alkyl group having 6 carbon
atoms. The second one is an ester of the same type,
with however n=2, all the R2 groups being methyl
groups, the two R5 groups being respectively linked to
the R6 and R7 groups to form two C6 alkyl groups.
The oligomeric or polymeric phosphorus compounds,
presented thus far as linear or cyclic chains, may also
be crosslinked networks, the various predominantly
carbon-based substituents being able to be themselves
linked to at least one other phosphorus atom, for
example when these substituents are polyols or

- 10 -
polyacids.
The latter compounds may in particular be obtained by
esterification or transesterification reactions between
acids or esters, that are phosphonic and phosphoric
respectively, and polyols (in particular diols),
polyacids (in particular diacids) or else epoxy
compounds. Within this scope, molasses (a by-product of
sugar refining) are a particularly attractive source of
polyols or diols due to their low cost. 1; appeared
that the phosphorus compounds according to the
invention were able to be obtained by reaction between
molasses and the phosphoric or phosphonic acids or
esters, this reaction which may even be carried out by
simultaneously spraying the two products on the fibers.
Phosphorus-based starches may also be employes.
The mineral wool according to the invention ion may
advantageously comprise a mixture of several phosphorus
compounds such as described previously.
The point that is common to these compounds, which
could be termed "organophosphorus compounds", is the
presence of carbon-based compounds within the
phosphorus chain itself, which seems to bo the origin
of the "blocking" of acid compounds, such at phosphoric
acid, for temperatures below 200°C and therefore of the
stability of these compounds against the effects of
temperature and moisture.
The phosphorus compound according to the invention is
preferably present in an amount greater than or equal
to 0.05%, especially 0.1%, and less than or equal to
2%, especially 1%. This quantity corresponds to the
mass of phosphorus compounds relative to the total mass
of fibers.
Considering the mass of phosphorus in there types of
compounds, the mass content of phosphorus atoms

- 11 -
relative to the mass of fibers is advantageously
between 0.0005% to 1%, especially greater than or equal
to 0.01% and even 0.1% and less than or equal to 0.5%.
The observed coating may be continuous on the surface
of a fiber and its thickness is especially between 0.01
and 0.05 urn.. Crystallization of a composition close to
that of the coating may also be observed locally on the
surface of the fibers and may reach thicknesses of
around 0.1 to 0.5 m.
According to one advantageous embodiment of the
invention, the coating that can form on the surface of
the mineral wool fibers potentially consists of an
alkaline-earth metal phosphate.
Coatings are thus obtained in which the composition is
close to that of crystals of the alkaline-earth metal
orthophosphate or pyrophosphate type, the melting point
of which is known to be above 1000°C.
Advantageously, the alkaline-earth metal phosphate that
can form on the surface of the mineral wool fibers is a
lime phosphate.
Lime phosphates, especially orthophosphates (Ca3(PO4)2,
or pyrophosphate (Ca2P2O7) , are known to be refractory
and these compounds have melting points of 1670°C and
1230°C respectively.
As described in application WO 01/68546, a cooperative
effect is observed between the fibers that form the
subject of the selection of the above constituents and
the phosphorus compounds. It may be considered that the
phosphorus compound releases, at high temperature (but
below 1000°C), phosphoric acid and/or phosphoric
anhydride, which starts to react with the fibers of the
composition according to the invention. In the case of
these compositions, the high alkaline metal content

- 12 -
that they have may act as a compensator for the charge
of aluminum, which is also present at high contents.
Thus these are compositions in which the atomic
mobility of the alkaline-earth metals is greater than
that of these elements in other glass compositions.
These relatively mobile alkaline-earth metals are then
capable of reacting with the phosphoric acid or
phosphoric anhydride to form a refractory compound,
especially an alkaline-earth metal phosphate, and thus
make it possible to ensure that the mineral wools
according to the invention exhibit excellent thermal
stability.
Thermally stable mineral wool capable of being
dissolved in a physiological medium is thus obtained.
In the rest of the text, the term "composition" will
refer to the ranges of the constituents of the fibers
of the mineral wool, or of the glass intended to be
fiberized in order to produce said fibers. Any
percentage of a constituent of the composition must be
understood to be a percentage by weight, and the
compositions according to the invention may include up
to 5%, especially 3%, of compounds considered as
unanalyzed impurities, as is known in this kind of
composition.
According to a variant of the invention, the
composition of the mineral wool is as follows:
SiO2 • 39-55%, preferably 40-52%
A12O3 16-27%, 16-25%
CaO 3-35%, 10-25%
MgO 0-15%, 0-10%
Na2O 0-15%, 6-12%
K2O 0-15%, 3-12%
R2O (Na2O + K2O) 10-17%, 12-17%
P2O5 0-5%, 0-2%
Fe2O3 0-15%,
B2O3 0-8%, 0-4%

- 13 -
TiO2 0-3%,
MgO being between 0 and 5%, especially between 0 and 2%
when R2O13.0%.
By selecting such a composition it is possible to
combine the whole series of advantages, especially by
varying the many complex roles that a number of its
specific constituents play.
Specifically, it has been found that the combination of
a high alumina content, of between 16 and 27%,
preferably greater than 17% and/or preferably less than
25%, especially less than 22%, for a sum of network-
forming elements, namely silica and alumina, of between
57 and 75%, preferably greater than 60% and/or
preferably less than 72%, especially 70%, with a high
quantity of alkali metals (R2O: sodium and potassium)
between 10 and 17%, with MgO between 0 and 5%,
especially between 0 and 2%, when R2O13.0%, makes it
possible to obtain glass compositions possessing the
remarkable property of being fiberizable within a very
wide range of temperatures and imparting biosolubility
in acid pH on the fibers obtained. According to
embodiments of the invention, the alkali metal content
is preferably greater than 12%, especially 13.0% and
13.3%, and/or preferably less than 15%, especially less
than 14.5%.
This compositional range proves to be particularly
beneficial as it has been observed, contrary to
received opinion, that the viscosity of the molten
glass does not decrease significantly with an increase
in alkali metal content. This remarkable effect makes
it possible to increase the difference between the
temperature corresponding to the viscosity for
fiberizing and the liquidus temperature of the phase
that crystallizes, and thus to considerably improve the
fiberizing conditions and especially makes it possible
to fiberize a new family of biosoluble glasses by

- 14 -
internal centrifugation.
According to one embodiment of the invention, the
compositions have an iron oxide content of between 0
and 5%, especially greater than 0.5%, and/or less than
3%, especially less than 2.5%. Another embodiment is
obtained with compositions that have an iron oxide
content of between 5 and 12%, especially between 5 and
8%, thereby making it possible to obtain fire-resistant
mineral wool blankets.
Advantageously, the compositions according to the
invention satisfy the relationship: (Na2O + K2O)/A12O3) >
0.5, preferably (Na2O + K2O) / A12O3) > 0.6, especially
(Na2O + K2O) / A12O3) > 0.7, which appears to favor the
temperature corresponding to the viscosity for
fiberizing higher than the liquidus temperature being
obtained.
According to a variant of the invention, the
compositions according to the invention preferably have
a line content of between 10 and 25%, especially
greater than 12%, preferably greater than 15%, and/or
preferably less than 23%, especially less than 20% and
even less than 17%, combined with a magnesia content of
between 0 and 5%, preferably with less than 2%
magnesia, especially less than 1% magnesia, and/or a
magnesia content greater than 0.3%, especially greater
than 0.5%.
According to another variant, the magnesia content is
between 5 and 10% for a line content between 5 and 15%,
and preferably between 5 and 10%.
By adding P2O5, which is optional, with contents of
between 0 and 3%, especially greater than 0.5% and/or
less than 2%, makes it possible to increase the
biosolubility in neutral pH. Optionally, the
composition may also contain boron oxide, which may

- 15 -
help to improve the thermal properties of the mineral
wool, especially by tending to lower its thermal
conductivity coefficient in the radiative component and
also to increase the biosolubility in neutral pH. It
may also include TiO2 in the composition, optionally,
for example up to 3%. Other oxides, such as BaO, SrO,
MnO, Cr2O3, ZrO2 and SO3 may be present in the
composition, with a total content not exceeding 5%,
preferably about 3 or 2%, and even 1%. These various
oxides may be intentionally added to the composition
according to the invention, but in general they are
present as inevitable impurities resulting from the
batch materials, from the refractory materials in
contact with the glass, or from the refining agents
employed to reduce the amount of gaseous inclusions in
the mass of molten glass.
According to one particularly preferred embodiment of
the invention, the mineral wool comprises fibers whose
constituents are mentioned below, in the following
percentages by weight:
SiO2 39-55%, preferably 40-52%
A12O3 16-27%, 16-26%
CaO 6-20%, 8-18%
MgO 0-5%, 1-4.9%
Na2O 0-15%, 2-12%
K2O 0-15%, 2-12%
R2O (Na2O + K2O) 10-14.7%, 10-13.5%
P2O5 0-3%, especially 0-2%
Fe2O3 (total iron) 1.5-15%, 3.2-8%
B2O3 0-2%, preferably 0-1%
TiO2 0-2%, 0.4-1%.
These compositions by themselves have a remarkably
improved high-temperature behavior.
It would seem that this composition range makes it
possible for crystallization seeds to be nucleated at
low temperature, these seeds causing the appearance or

- 16 -
the growth of crystals at a sufficiently low
temperature at which the softening or sintering of the
material is not yet able to be effective. It may be
considered that, by crystallizing components more
fusible than the overall glass composition, the
viscosity of the residual glass increases and the
surface forces involved for sintering are no longer
high enough to prevail over the viscous cohesion
forces.
Preferably, the alumina is present in an amount of 17
to 25.5%, especially 20 to 25%, in particular 21 to
24.5% and especially around 22 to 23 or 24% by weight.
Advantageously, good refractoriness may be obtained by
adjusting the magnesia content, especially to at least
1.5%, in particular 2%, especially greater than or
equal to 2.5% or 3%. A high magnesia content is
conducive to a low-temperature crystallizing effect
that opposes the lowering of viscosity generally
observed at high temperature, and therefore prevents
the material from sintering.
One advantageous composition selection consists in
providing the required minimum amount of magnesia, this
being greater the lower the amount of alumina.
Thus, when the alumina is present in an amount of at
least 22% by weight, the amount of magnesia is
preferably at least 1%, advantageously around 1 to 4%,
preferably 1 to 2% and in particular 1.2 to 1.6%. The
alumina content is preferably limited to 25% in order
to preserve a sufficiently low liquidus temperature.
When the alumina is present in a lower amount, for
example around 17 to 22%, the amount of magnesia is
preferably at least 2%, especially around 2 to 5%.
The lime is advantageously present at contents of
between 9.5 and 20%, preferably between 10 and 18% and

- 17 -
even more preferably from 11 to 16%.
The total amount of lime and magnesia may
advantageously be around 14 to 20%, especially 15 to
19%.
The total amount of alkaline-earth metal oxides (lime,
magnesia, barium oxide and strontium oxide) is
preferably between 10 and 20%, especially from 12 to
18%.
The amount of silica is advantageously around 35 to
50%, especially 37 to 48% and more particularly 39 to
4 4%, by weight.
Depending on the embodiments of the invention, the
alkali metal oxide content is preferably less than or
equal to 13.2%, or even 13.0%, especially around 10 to
12.5% and in particular 10.2 to 12% or Jess.
Sodium oxide and potassium oxide may each be present in
an amount of 3 to 9% by weight.
Within this range of alkali metal oxide contents, it
proves advantageous to choose a ratio of the alkali
metal oxide content to alumina content such that the
R2O/Al2O3 molar ratio is less than 1, in particular less
than 0.9, especially at most 0.8 and in particular at
most 0.75.
When the molar ratio is greater than 0.9, it is
preferable for the magnesia content to be high enough
to produce a low-temperature crystallizing effect, for
example at least 2%, or at least 2.5%, otherwise
excessively low glass transition temperatures would be
obtained, with a deleterious effect on the behavior at
very high temperature.
An R2O/Al2O3 molar ratio of less than 0.9 produces a
favorable effect on refractoriness, in particular at

- 18 -
low temperature, and therefore on the softening point
and the sintering temperature.
However, within this composition range a sufficiently
large difference is maintained between the temperature
corresponding to the viscosity for fiberizing and the
liquidus temperature of the phase that crystallizes -
thus giving good fiberizing conditions.
The iron oxide present in the composition has a
positive impact on the nucleation of growth of seeds at
low temperature, while still limiting the liquidus.
However, its amount is preferably limited so as not to
adversely affect biosolubility in acid medium. In a
preferred embodiment of the invention, the compositions
have iron oxide contents of between 2 and 6%,
preferably around 3 to 6%.
The titanium oxide provides a very noticeable effect on
the nucleation at high and low temperature of spinels
within the glassy matrix. A content of the order of 1%
or less may prove to be advantageous.
P2O5 may be used, at contents of between 0 and 3%,
especially between 0.1 and 1.2%, to increase the
biosolubility at neutral pH.
Other oxides, such as BaO, SrO, MnO, Cr2O3 and ZrO2, may
be present in the composition, with a maximum total
content of 5%, or even 2%, and even 1%.
The difference between the temperature corresponding to
a viscosity of 102'5 poise (decipascal.second) , denoted
by T1og2.5, and the liquidus of the crystallizing phase,
denoted by Tliq, is preferably at least 10°C. This
difference, Tlog2.5 - Tiiq, defines the "working range"
for the compositions of the invention, that is to say
the temperature range within which fiberization is
possible, most particularly by an internal centrifugal

- 19 -
process. This difference is preferably at least 20 or
30°C, and even more than 50°C, especially more than
100°C.
The compositions according to the invention have high
glass transition temperatures, especially above 600°C.
Their annealing temperature, denoted by Tannealing, is
especially above 600°C.
As mentioned above, the mineral wool exhibits a
satisfactory level of biosolubility especially at acid
pH. It thus has in general a rate of dissolution,
especially measured on silica, of at least 30 and
preferably at least 40 or 50 ng/cm2 per hour measured
at pH 4.5 using a method similar to that described in
the NF T 03-410 standard.
Another very important advantage of the invention
relates to the possibility of using inexpensive batch
materials to obtain the composition of these glasses.
These compositions may especially result from the
melting of rock, for example of the phonolite type,
with an alkaline-earth metal carrier, for example
limestone or dolomite, if necessary supplemented with
iron ore. By this means, a moderate-cost alumina
carrier is obtained.
This type of composition, with a high alumina content
and a high alkali metal oxide content, may
advantageously be melted in fired glass furnaces or
electric glass furnaces.
The subject of the invention is also a process for
obtaining mineral wool according to the invention,
which includes a step of fiber-forming followed by a
step of supplying, especially by spraying or
impregnation of a solution, at least one phosphorus
compound onto the surface of said fibers.

- 20 -
The subject of the invention is also a thermal and/or
acoustic insulation product comprising at least one
mineral wool according to the invention.
The invention also relates to the use of the mineral
wool described above in fire-resistant structural
systems.
The expression "fire-resistant structural systems" is
understood to mean systems generally comprising
assemblies of materials, especially based on mineral
wool and metal plates, that can effectively retard the
propagation of heat and also provide protection against
flames and hot gases and maintain mechanical strength
during a fire.
Standardized tests define the degree of fire
resistance, expressed especially as the time needed for
a given temperature to be reached on the opposite side
of the structural system that is exposed to a heat flux
generated, for example, by the flames of a burner or by
an electric furnace.
A structural system is considered to exhibit
satisfactory fire resistance if it is able in
particular to meet the requirements of one of the
following tests:
fire door test: tests on mineral fiber boards,
as defined in the German standard DIN 18 089 - Part 1
(or equivalent);
- fire behavior of building materials and
elements, as defined in the German standard DIN 4102
(or equivalent). In particular, the standard DIN 4102 -
Part 5 is considered for full-scale tests so as to
determine the fire resistance class, and/or the
standard DIN 4102 - Part 8 for tests on specimens with
a small test bed; and
normalized test OMI A 754 (18) (or equivalent),
which describes the general fire resistance test

- 21 -
requirements for "marine"-type applications, especially
for ship bulkheads. These tests are carried out on
large specimens, with 3 m by 3 m furnaces. Mention may
be made, for example, of the case of a steel deck on
which the required performance in the case of a fire on
the insulation side is to meet the thermal insulation
criterion for at least 60 minutes.
Other details and advantageous features will become
apparent from the description below of nonlimiting
preferred embodiments.
Table 1 below gives the compositions of the fibers, in
percentages by weight, of sixty examples.
The "impurities" line corresponds to the inevitable
impurities resulting from the batch materials, from the
refining agents or from the refractory materials in
contact with the molten glass, treated globally. Only
their total content is indicated, purely by way of
indication, as neither their content, in general less
than 2%, or even less than 1%, nor their nature affect
the way in which the examples according to the
invention solve the stated problem.
The compositions according to these examples can be
fiberized by an internal centrifugal process,
especially according to the teaching of the
aforementioned Patent WO 93/02977.
Their working ranges, defined by the difference
T1Og2.5 - Tliq, are largely positive, especially greater
than 50°C, or even 100°C and even greater than 150°C.
The liquidus temperatures are relatively low,
especially not exceeding 1200°C and even 1150°C.
The temperatures (Tlog2.5) corresponding to viscosities
of 102.5 poise are compatible with the use of

- 22 -
centrifugal spinners for high-temperature fiberizing,
especially under the operating conditions described in
Application WO 93/02977.
The preferred compositions are in particular those in
which T1Og2.5 is less than 1350°C, preferably less than
1300°C.
Table 1 also indicates the annealing temperature
(expressed in °C) and the rate of dissolution of the
fibers at pH 4.5 (expressed in ng/cm2.h). The latter
quantity, measured according to the protocol indicated
in standard NF T 03-410, is greater than 30 ng/cm2.h.
To illustrate the present invention, various phosphorus
compounds were added during the fiberizing process, by
spraying them, in a zone located after the zone in
which the fibers are attenuated from the molten glass
and before the zone in which the mineral wool is
collected. The term "adjuvants" refers to the compounds
added in this spraying zone, which adjuvants may be
supplied simultaneously or separately.
The composition of example 45 of Table 1 was fiberized
by the internal centrifugal process with or without the
presence of various phosphorus-based compounds, in
order to obtain mineral wool blankets, and the results
of mechanical thermo stability tests are given in
Table 2.
In these tests, the adjuvant comprises a resin-based
binder and, in certain examples, a phosphorus compound
added to this binder and sprayed at the same time as
the latter.
The resin-based binders, well-known in the mineral wool
field, have the function of giving the fiber blanket
the desired mechanical strength. Within the context of
the present tests, a standard binder based on a phenol-

- 23 -
formaldehyde resin and urea has been employed. Other
types of sizing composition, in particular those that
are formaldehyde-free, may, of course, also be used,
alone or in mixtures. They may be for example:
- compositions based on an epoxy resin of the
glycidyl ether type and a non-volatile amine hardener
(described in Application EP-A-0 369 848), which may
also comprise an accelerator chosen from imidazoles,
imidazolines and mixtures thereof;
compositions comprising a carboxylic polyacid
and a polyol, preferably combined with a catalyst of
the alkali metal salt of a phosphorus-containing
organic acid type (described in Application EP-A-0 990
727);
compositions comprising one or more compounds
incorporating a carboxylic functional group and/or a
-hydroxyaikylamide functional group (described in
Application WO-A-93/36368);
- compositions incorporating either a carboxylic
acid and an alkanolamine, or a resin previously
synthesized from a carboxylic acid and from an
alkanoiamine, and a polymer containing a carboxylic
acid group (described in Application EP-A-1 164 163);
sizing compositions prepared in two steps
consisting in mixing an anhydride and an amine under
reactive conditions until the anhydride is
substantially dissolved in the amine. and/or has reacted
with it, then in adding water and terminating the
reaction (described in Application EP-A-1 170 265) ;
- compositions containing a resin that comprises
the polymer-free reaction product of an amine with a
first anhydride and a second anhydride that is
different from the first (described in Application EP-
A-1 086 932);
compositions containing at least one
polycarboxylic acid and at least one polyamine;
- compositions comprising copolymers of carboxylic
acid and of monomers containing alcohol functional
groups such as described in Application US 2005/038193;

- 24 -
and
- compositions comprising polyols and polyacids or
polyanhydrides such as maleic acid, described for
example in Patent WO 2005/87837 or in Application
US 6 706 808.
These application or patents EP-A-0 369 848, EP-A-0 990
727, WO-A-93/36368, EP-A-1 164 163, EP-A-1 170 265, EP-
A-l 086 932, US 2005/038193, WO 2005/87837, US
6 706 808 are incorporated as reference into the
present application, along with applications
WO 04/007395, WO 2005/044750, WO 2005/121191, WO
04/094714, WO 04/011519, US 2003/224119, US
2003/22 4120.
Aminoplast type resins (melamine-formaldehyde or urea-
formaldehyde) may also be used within the scope of. the
invention.
Comparative example A contained no phosphorus compounds
and there formed only the resin-based binder as
adjuvant.
In the case of the other examples, six different
phosphorus compounds were employed. The first three
were mineral phosphates or polyphosphates quite similar
to those described in application WO 01/68546 and were
employed in comparative examples B, C and D. These were
the following:
sodium metaphosphate. Comparative example B
contained 0.2% thereof;
- a flame retardant with the trade name "EXOLIT AP
4 62" produced by Clariant GmbH. Based on a ammonium
polyphosphate and melamine, it is especially used to
improve the fire resistance of polymers (polyurethanes,
epoxy resins) and has a very low water solubility.
Comparative example C contained 0.2% thereof; and
- a flame retardant with the brand name "FR CROS
489" sold by Buddenheim (CAS No. 68333-79-9) . This

- 25 -
product is an ammonium polyphosphate containing 64%
phosphorus expressed in P2O5 form. Comparative example D
contained 0.2% thereof.
The other three phosphorus compounds were
"organophosphorus" compounds employed within the
context of the present invention. These were the
following:
- a flame retardant with the trade name "EXOLIT OP
550" produced by Clariant GmbH. Based on a phosphoric
polyester type oligomer, it is especially used as an
agent for protecting polyurethanes against: fire.
Examples E, F and G according to the invention
respectively contained 0.3%, 0.5% and 0.7% of it
relative to the total mass of fibers; and
- a flame retardant with a brand name "EXOLIT OP
560" produced by Clariant GmbH. Based on an oligomer of
the phosphonic polyester type, it is employed in
particular as an agent for protecting polyurethanes
against fire. Example H according to the invention
contained 0.5% thereof; and
- a flame retardant with the trade name "FYROL
PNX" sold by Akzo Nobel, containing 19% of P2O5. It; is a
phosphoric polyester type oligomer of formula (3) in
which n varies between 2 and 20, R6, R7 and RB are ethyl
groups and R5 is an ethylene group (CAS number 184538-
58-7). Example I according to the invention contained
0.8% of it.
These three compounds contain phosphorus atoms and
carbon-containing entities, in particular of the alkyl
type, in their main chain.
Among other examples of phosphorus compounds according
to the invention are the products BUDIT 341 or 3118F
sold by Buddenheim. The mixture of cyclic phosphonic
esters sold under the trademark AMGARD© CT or CU by
Rhodia is also particularly interesting. This product,
used as a fire retardant for polyester-based textiles,

- 26 -
has in fact a higher stability than the product EXOLIT
OP 550 at the temperature of the oven, and thus makes
it possible to obtain better mechanical properties
before aging. Its P2O5 content is about 20%.
Table 2 gives, for all of these tests, the initial
mechanical strength of the mineral wool products
obtained and the loss of their mechanical strength (as
a relative percentage) after ageing in an autoclave at
105°C under a pressure of 1.5 bar for 15 minutes, and
for some of these tests the slump at 1000°C, according
to the draft standard "insulating materials: thermal
stability" mentioned above.
The mechanical strength was measured before and after
autoclave ageing by tensile tests carried out on
specimens in the form of rings cut from the fibrous
products with a density of 14 kg/m3. According to this
test, two pins were introduced into the center of the
ring and moved apart at a constant rate until the
specimen broke. This strength, expressed in N/g,
corresponds to the force at break divided by the mass
of the specimen. The test was repeated on twenty
specimens, the average of the results obtained being
indicated in the table.

- 27 -
Table 2

These results clearly show that the addition of
phosphorus compounds such as those described in the
prior art (examples B, C and D) do not improve the
initial mechanical strength properties or degrade them
(upon leaving the oven) and also greatly degrade the
variation in these properties over time compared with
the case in which no phosphorus compound was added
(example A).
In contrast, the use of the phosphorus compounds within
the context of the present invention, on the one hand,
improves the initial mechanical properties of the
product and, on the other hand, either does not degrade
the variation in these properties after accelerated
ageing (examples F, H and I) or even improves them
(examples E and G) .
Without wishing to be tied by any scientific theory,
the beneficial effect of adding the compounds according
to the invention seems to be due to the absence of acid
compounds being liberated, such as phosphoric acid
and/or phosphoric anhydride, during the oven treatment
for curing the resin of the binder and during the
accelerated ageing treatment on the end product. This
is because it seems that the liberation of acid
compounds causes the adhesion between the binder and

- 28 -
the glass fibers to be reduced and/or attacks the
surface of the fibers. It has also been demonstrated
independently of the present invention that the
addition of a base (such as MgO) as additional adjuvant
makes it possible to neutralize the acids formed during
this binder curing step and offers advantages with
regard to the variation in mechanical properties over
time of the products thus formed.
The beneficial effect of all these types of phosphates
(comparative example B or examples E and I according to
the invention) on the thermal stability is also
confirmed, the slump at 1000°C being reduced by at
least a factor of two compared with that of fibers
without phosphate compounds.

WO 2006/103375 PCT/FR2006/050280
- 35 -
CLAIMS
1. A thermally stable mineral wool capable of
dissolving in a physiological medium, which comprises
fibers whose constituents are mentioned below, in the
following percentages by weight:
SiO2 35-60%, preferably 39-55%
A12O3 12-27%, 16-25%
CaO 0-35%, 3-25%
MgO 0-30%, 0-15%
Na2O 0-17%, 6-12%
K2O 0-17%, 3-12%
R2O (Na2O + K2O) 10-17%, 12-17%
P2O5 0-5%, 0-2%
Fe2O3 0-20%,
B2O3 0-8%, 0-4%
TiO2 0-3%,
and at least one phosphorus compound capable of
reacting at a temperature below 1000°C with said fibers
in order to form a coating on the surface of said
fibers, said compound characterized in that the
content, expressed by weight: of phosphorus atoms varies
from 0.0005%, especially more than 0.01% to 1%, but
especially less than 0.5% of the total mass of the
fibers, and in that a phosphorus compound being a
molecule in which the phosphorus atom(s) is (are)
linked to at least one carbon atom, directly or via an
oxygen atom.
2. The mineral wool as claimed in claim 1,
comprising at least one phosphorus compound chosen
from:
a) a molecule containing a single phosphorus
atom linked to at least one carbon atom, strictly by
means of an oxygen atom;.
b) a molecule containing a single phosphorus
atom linked directly to at least one carbon atom.
3. The mineral wool as claimed in the previous
claim, comprising at least one phosphorus compound (a)

- 3 6 -
chosen from: a mono-, di- or tri-phosphoric ester, or
an unsubstituted phosphonic or phosphinic ester, the
carbon-based groups of these esters being alkyl, aryl,
acyl or hydroxyalkyl compounds, which may possibly be
of oligomeric or polymeric nature and/or contain one or
more heteroatoms chosen from N, 0 or S.
4. The mineral wool as claimed in claim 2,
comprising at least one phosphorus compound (b) chosen
from an at least partially substituted phosphonic or a
mono-, di- or tri-phosphinic ester or acid, the various
carbon-based groups of these compounds being alkyl,
aryl, acyl or hydroxyalkyl compounds, which may
possibly be of oligomeric or polymeric nature and/or
contain one or more heteroatoms chosen from N, 0 or S.
b. The mineral wool as claimed in claim 1,
comprising at least one phosphorus compound that is a
molecule made up of several compounds of type (a) or
(b) as claimed in claims 2 to 4, that are identical or
different., linked together by covalent bonds.
6. The mineral wool as claimed in the previous
claim, comprising at least one phosphorus compound that
is an oligomer or polymer molecule, of which the number
of constituent units is preferentially between 2 and
100, especially 2 and 50, or even between 2 and 10.
7. The mineral wool as claimed in claim 5 or 6,
comprising at least one phosphorus compound that
contains predominantly phosphorus atoms linked together
via a carbon-based entity.
8. The mineral wool as claimed in the previous
claim, comprising at least one phosphorus compound that
may be represented according to the genera] formula (1)
below:

- 37 -
in which:
- n is between 1 and 100, preferably between 1
and 50, especially between 2 and 10;
the substituents R1 to R4 are identical or different,
predominantly carbon-based entities, preferably of
possibly branched alkyl, aryl, acyl or hydroxyalkyl
type, which may possibly be of oligomeric or polymeric
nature and/or contain one or more heteroatoms chosen
from N, O, S or P.
9. The mineral wool as claimed in the previous
claim, comprising at least one phosphorus compound that
is a phosphonic polyester-type oligomer or polymer of
general formula (2) below:

in which:
- the chain length n is between 1 and 100,
preferably between 1 and 50, especially between 2 and
10; and
- the substituents R2 and R5 to R7 are identical
or different, predominantly carbon-based entities,
preferably of possibly branched alkyl, aryl, acyl or
hydroxyalkyl type, which may possibly be of oligomeric
or polymeric nature and/or contain one or more
heteroatoms chosen from N, 0, S or P.
10. The mineral wool as claimed in claim 8,
comprising at least one phosphorus compound that is a
phosphoric polyacid or polyester-type oligomer or
polymer of general formula (3) below:

in which:
the chain length n is between 1 and 100,
preferably between 1 and 50, especially between 2 and
10;
- the substituents R5 to R8 are identical or
different, predominantly carbon-based entities,
preferably of possibly branched alkyl, aryl, acyl or
hydroxyalkyl type, which may possibly be of oligomeric
or polymeric nature and/or contain one or more
heteroatoms chosen from N, O, S or P.
11. The mineral wool as claimed in one of claims
4 to 10, comprising at least one phosphorus compound
that is obtained by an ester Lfication or
transesterification reaction between acids or esters,
that are phosphonic and phosphoric respectively, and
polyols (in particular diols), polyacids (in particular
diacids) or epoxy compounds.
12. The mineral wool as claimed in the previous
claim, comprising at least one phosphorus compound that
is obtained by reaction between molasses and the
phosphoric or phosphonic acids or esters.
13. A mineral wool as claimed in one of the
preceding claims, comprising fibers who constituents
are mentioned below, the following percentages by
weight:
SiO2 39-55%, preferably 40-52%
A12O3 16-27%, 16-25%
CaO 3-35%, 10-25%
MgO 0-15%, 0-10%
Na2O 0-15%, 6-12%
K2O 0-15%, 3-12%
R2O (Na-0 -1- K2O) 10-17%, 12-17%
p2O3 0-5%, 0-2%

- 39 -
Fe2O3 0-15%,
B2O3 0-8%, 0-4%
TiO2 0-3%,
MgO being between 0 and 5%, especially between 0 and 2%
when R2O13.0%.
14. The mineral wool as claimed in one of the
preceding claims, comprising fibers whose constituents
are mentioned below, in the following percentages by
weight:
SiO2 39-55%, preferably 40-52%
A12O3 16-27%, 16-26%
CaO 6-20%, 8-18%
MgO 1-5%, 1-4.9%
Na2O 0-15%, .2-12%
K2O 0-15%, 2-12%
R2O (Na2O + K2O) 10-14.7%, 10-13.5%
P2O5 0-3%, especially 0-2%
Fe2O3 (Total Iron) 1.5-15%, 3.2-8%
B2O3 0-2%, preferably 0-1%
TiO2 , 0-2%, 0.4-1%.
15. The mineral wool as claimed in one of the
preceding claims, such that the CaO content is between
9.5 and 20%, preferably between 10 and 18%.
16. The mineral wool as claimed in one of the
preceding claims, containing 20 to 25% alumina.
17 . A mineral wool as claimed in one of the
preceding claims, containing at least 2%, especially
around 2 to 5%, MgO when the alumina is present in an
amount of less than 22%, especially 17 to 22%, and
containing 1 to 4%, preferably 1 to 2%, MgO when the
alumina is present in an amount of at least 22% by
weight.
18. The mineral wool as claimed in one of the
preceding claims, such that the alkaline metal content
is preferably less than or equal to 13.0%, especially
around 10 to 12.5%, in particular 12% or less.
19. The mineral wool as claimed in one of the
preceding claims, such that the R2O/A12O3 molar ratio is

- 40 -
less than 0.9, especially at most 0.8, in particular at
most 0.75.
20. The mineral wool as claimed in one of the
preceding claims, containing 2 to 6% iron oxide.
21. The mineral wool as claimed in one of the
preceding claims, containing 1% titanium oxide or less.
22. The mineral wool as claimed in one of the
preceding claims, such that the fibers have a rate of
dissolution of at least 30 ng/cm2 per hour measured at
pH 4.5.
23. The mineral wool as claimed in one of the
preceding claims, in which the glass corresponding to
the fibers may be fiberized by the internal centrifugal
process.
24. The mineral wool as claimed in one of the
preceding claims, in which the coating that: can be
formed on the surface of the fibers essentially
consists of an alkaline-earth metal phosphate.
25. The mineral wool as claimed in the preceding
claim, in which the alkaline-earth metal phosphate is a
lime phosphate.
26. A process for obtaining mineral wool as
claimed in one of the preceding claims which includes a
step of fiber-forming followed by a step of supplying,
especially by spraying or impregnation of a solution,
at least one phosphorus compound onto the surface of
said fibers.
27. The use of the mineral wool as claimed ;n
any one of the preceding mineral wool claims in fire-
resistant structural systems.
28. A thermal and/or acoustic insulation product
comprising at least one mineral wool as claimed in one
of the preceding mineral wool claims.

The invention relates to thermally stable mineral wool which can dissolve in a
physiological medium, comprising fibres containing the following constituents,
expressed in percentage by weight, namely : 35-60% SiO2, preferably 39.55%,
12-27% AI2O3, preferably 16-25%; 0.35% CaO, preferably 3-25% CaO,
preferably 3-25%,; 0-30% MgO, preferably 0-15%, 0-17% Na2O, preferably
6-12%, 0-17% K2O, preferably 3-12%, 10-17% R2O(Na2O + K2O), preferably
12-17%;0-5%P2O5, preferably 0-2%;0-20%Fe2O3; )-8%B2O3, preferably 0-4%,
and 0.3% TiO2, and at least one phosphorous compound that can react with said
fibres at a temperature of less than 1000oC in order to form a coating on the
surface thereof. The invention is characterised in that the phosphrous content of
said compound, as expressed in phosphorus atom weight, varies between
0.0005%, in particular more than 0.01%, and 1%, in particular less than 0.5%,
of the total weight of the fibres. The invention is also characterised in that a
phosphorus compound is a molecule in which the phosphorus atom(s) are bound
to at least one carbon atom either directly or by means of an oxygen atom.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=M6i/lkSBSdzhnahbeK1aTQ==&loc=wDBSZCsAt7zoiVrqcFJsRw==

« Previous Patent

Next Patent »

Patent Number

272819

Indian Patent Application Number

3606/KOLNP/2007

PG Journal Number

18/2016

Publication Date

29-Apr-2016

Grant Date

27-Apr-2016

Date of Filing

24-Sep-2007

Name of Patentee

SAINT-GOBAIN ISOVER

Applicant Address

18 AVENUE D'ALSACE F-92400 COURBEVOIE

Inventors:

#	Inventor's Name	Inventor's Address
1	DOUCE, JEROME	19 RUE MONTGALLET, F-75012 PARIS
2	BERNARD, JEAN-LUE	51, RUE ANDRE OUDEN, GIENCOURT, F-60600 CLERMONT

PCT International Classification Number

C03C 25/42

PCT International Application Number

PCT/FR2006/050280

PCT International Filing date

2006-03-31

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	0550860	2005-04-01	France