Title of Invention

A HIGHLY WEATHERABLE, MOISTURE-CURABLE, ONE-COMPONENTPOLYURETHANE COMPOSITION.

Abstract A Highly weatherable, moisture-curable, one-component polyurethane composition, which is characterized by being curable with moisture in the air,and containing a main component, which will form a polyurethane resin upon curing, and additives. wherein said additives comprise one or more photocurable materials selected from the group consisting of unsaturated acrylic compounds, polyvinyl cinnamate and azide-containing compounds, and a hindered amine photostabilizer.
Full Text HIGHLY WEATHERABLE MOISTURE-CURABLE ONE-COMPONENT
POLYURETHANE COMPOSITIONS
Background of the invention
1. Field of the Invention
The present invention relates to highly weatherable, moisture-curable,
one-component polyurethane compositions which are suitably used as sealants,
inner and outer use adhesives, and waterproofing materials for roofs and wall
surfaces.
2. Description of the Prior Art
Conventionally, moisture-curable, one-component polyurethane
compositions have mainly been used as selants, inner and outer use adhesives,
and waterproofing materials for roofs and wall surfaces. These have, however,
not been free from the problems, such as early surface deterioration and crack
formation in cured products, when used under exposition to the outdoor
environment.
With such backgrounds, the conventional moisture-curable, one-
component polyurethane compositions have been prepared by addition of an
antioxidant to retard the surface deterioration.
Further, a polyester having an excellent weatherability have been used
as the prepolymer to be blended into the moisture-curable, one-component
polyurethane composition, in place of the ordinary prepolymers.
Furthermore, in place of these moisture-curable, one-component
compositions have in part been used, which cause less surface deterioration at
the early stage of exterior exposition.
However, merely adding an antioxidant to the moisture-curable, one-
component poiyurethane compositions as mentioned above could not improve
the weatherability well, so that a recipe for further improvement is desired.
Although use of a polyester as the prepolymer performs a sufficient
improvement in the weatherability, economical problems are unavoidable,
because of the polyester prepolymers are more expensive than those
conventional prepolymers.
Also, the moisture-curable, modified silicone one-component
compositions have such problems as that the adhesive strength is lower, as
compared with the moisture-curable, one-component polyurethane
compositions, and that the degree of surface deterioration turns more significant
than those in moisture-curable, one-component polyurethane compositions,
when exposed to outdoor conditions for a fairly long period of time.
Summary of the Invention
In view of the above situations, an object of the present invention is to
provide moisture-curable, one-component polyurethane compositions having a
high weatherability, with a suppressed cost increase.
After exhaustive investigations to solve the problems as mentioned
above, the inventors have accomplished the present invention. Thus, moisture-
curable, one-component polyurethane compositions according to the present
invention are one-component (i.e. one-component or single liquid) compositions
curable with moisture in the air, and contain a main component which will form a
polyurethane resin upon curing, and additives, wherein said additives comprise
one or more photocurable materials selected from the group consisting of
unsaturated acrylic compounds, polyvinyl cinnamate and azide-containing
compounds, and a hindered amine photostabilizer.
The additives as mentioned above may preferably contain additionally a
blocked amine compound which will form a primary or secondary amine group
with moisture.
Further, the additives as above may preferably further contain a
thixotropy endowing agent comprising an inorganic filler treated with an organic
material selected from the group consisting of fatty acids, metal salts of fatty
acids, fatty acid esters, resinic acids, surface active agents and polyacrylates.
Furthermore, the above additives may preferably contain a thixotropy
endowing agent comprising a polyurea compound represented by the formula:
R1(NHCON-R2, -R3)m
wherein R1 is a residue originated from polyisocyanate; R2 and R3 are
residues each originated from a monoamine, and one of these residues may be
a hydrogen atom; and m is an integer of 2 to 4.
Preferably, the thixotropy endowing agent comprising a polyurea
compound may be added to the present composition in the form of a compound
may be added to the present composition in the form of a paste formed by
dispersing the agent in a phthaiate ester compound.
The present moisture-curable, one-component poiyurethane
compositions are highly weatherable, and can be provided with lower costs than
those using a polyester prepolymer or moisture-curable, modified silicone one-
component compositions.
Moreover, the storage stability and thixotropy of the present
compositions are much improved by blending a thixotropy endowing agent
comprising an above polyurea compound to the additives.
Description of the Preferred Embodiments
The present invention will more fully be described hereinafter. The
moisture-curable, one-part, polyurethane compositions according to the
invention are curable with moisture in the air. Thus they can be used, for
example, for filling up crevices between material parts. Particularly, they are
suitably used as sealants, inner and outer use adhesives, waterproofing material
for roofs and wall surfaces, and other usages in the exterior exposition situation.
The present moisture-curable, one-component poiyurethane
compositions are prepared by blending a main component, which will form a
poiyurethane resin upon curing, with additives.
The main component, which will form a poiyurethane resin upon curing
are not particularly limitative, and may be any of those already known. For
example, a prepoiymer having polypropylene oxide as the principal chain
skeleton and isocyanate group at the terminals is suitably used.
As for the isocyanate in such a prepolymer, there may be mentioned, for
example, toluene 2,4-diisocyanate, toluene 2,6-dilsocyanate, phenylene
diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate,
polyphenylmethane polyisocyanate (Polymeric MD1), naphtylene, 1,5-
diisocyanate, triphenylmethane triisocyanate, and diphenyl sulfone diisocyanate;
and those hydrogenated compounds, such as 1-methyl-2,4-
diisocyanateocyclohexane, 1-methyl-2,6diisocyanatocyclohexane, and
dicyclohexylmethane diisocyanate; ethylene diisocyanate, propylene
diisocyanate, tetramethylene diisocyanate; propylene diisocyanate,
tetramethylene diisocyanate, hexamethylene diisocyanate, and isophorone
diisocyanate; and a dimer (urethodione diisocyanate) and trimer (isocyanurate
triisocyanate) of these diisocyanates.
As for the additives used in the present invention, one ore more
photocurable materials selected from the group consisting of unsaturated acrylic
compounds, polyvinyl cinnamate and azide-containing compounds, are used,
together with a hindered amine photostabilizer.
Photocurable material readily suffers from a chemical change in its
molecular structure by rays of light within a fairly short period of time, with a
physical change such as curing. Such compounds include organic monomers,
oligomers, resins, and other compositions containing them. Typically, they are
unsaturated acrylic compounds, polyvinyl cinnamate and azide-containing
compounds, as mentioned above.
Suitable unsaturated acrylic compounds include acrylic and methacrylic
monomers having one or more unsaturated groups, their oligomers, and
mixtures thereof. There are illustrated propylene (or butylene or ethylene) glycol
di(meth)acrylate, neopentyl glycol di(meth)acrylate, tetramethylene
dimethacrylate, as monomers and oligomers having not higher than 10,000 of
molecular weight.
Polyvinyl cinnamate is a photosensitive resin having cinnamoyl group as
the photosensitive group, and includes that prepared by esterlfying polyvinyl
alcohol with cinnamic acid, and many other polyvinyl cinnamate derivatives.
Azide-containing compounds have been known as photosensitive resins
having azide group as the photosensitive group. Photosensitive rubber liquid
containing a diazide compound as photosensitizer, as well as those illustrated in
,,KANKOSEI JUSHI" (Photosensitive Resins), published on March 17, 1972, by
JNSATSU GAKKAI" (Printing Academy), pages 93-, 106-, and 117-, may be
used singly or as a mixture thereof. if desired, an additional sensitizer may be
added.
Such a photocurable material suffers from a chemical change in the
molecular structure by rays of light within a fairly short period of time, with a
physical change such a curing.
Thus, it forms a film at the surface of the cured composition, and
controls the effect of rays of light on polyurethane in the cured composition,
thereby restraining the deterioration of polyurethane and the formation of cracks.
Blending ratio of the photocurable material per the amount of the main
component as mentioned above (for example, a prepolymer having isocyanate
group at the terminals) is preferably 0.5 to 50 parts by weight per 100 parts by
weight of the main component. An amount less thanO.5 part by weight causes
insufficient photocurability in the resulting composition, which tends to provide
lower weatherability. A blending amount exceeding 50 parts by weight does not
improve the weatherability, when compared to that having 50 parts by weight
blended, accordingly such an amount is uneconimical.
As for the photocurable materials selected from the group consisting of
unsaturated acrylic compounds, polyvinyl cinnamate and azide-containing
compounds, any of those commercially available may be suitably used.
Among them, unsaturated acrylic compounds are particularly preferred,
because of effective improvement in the weatherability and the advantageous
cost of production.
Hindered amine photostabilizer includes UV absorbers, which absorbs
photoenergy such as from sun beams and fluorescent lamp to convert to
harmless heat energy, and quenchers which extinct the active center excited by
photoenergy. As for resins which readily deteriorates by light, heat stabilizer and
antioxidant may combinedly used along with the photostabilizer, thereby their
light resistance and weatherability being significantly improved.
Most of such hindered amine photostabilizers are commercially
available, and include, for example, ADEKASTAB LA-52, LA-57, LA-62, LA-67,
LA-63, LA-68, LA-77, LA-82 and, LA-87 (manufactured by ASAHI DENKA
KOGYO K.K.); bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-
pentamethyl-4-piperidyl) sebacate, 1 -[2-(3,5-di-tert-butyl-4-hydroxyphenyl)-
propionyloxy)ethyl]-4-[3-(3,5-di-tert-buty-4-hydroxyphenyl)propionyloxy]-2,2,6,6-
tetramethylpiperidyl succinate, dimethyl- 1 -(2-hydroxyethyl)-hydroxy-2,2,6,6-
tetramethylpiperidine polycondensate, poly[[6-1(1,1,3,3-tetramethylbuty)imino-
1,3,5-triazin-2,4-diyl][(2,2,6,6-tetramethyl-4-piperdyl)imino] hexamethylene
[(2,2,6,6-tetramethyl-4-piperclyl)imino]], bis(12,2,6,6-pentamethyl-4-piperidyl) 2-
(3,5-di-t-butyl-4-hydroxybenzyl)-2-n-butyl malonate and the like.
Hindered amine photostabilizer absorbs UV photoenergy, for example,
from sun beams and fluorescent lamp, to convert to harmless heat energy.
Thus, it controls UV absorption of polyurethane in the cured composition,
thereby restraining the UV deterioration of polyurethane and formation of cracks.
Blending amount of the hindered amine photostabilizer per the amount
of the main component as mentioned above (for example, a prepolymer having
isocyanate group at the terminals) is preferably 0.01 to 10 parts by weight per
100 parts by weight of the main component. An amount less than 0.01 part by
weight causes insufficient photostability in the resulting composition, which
causes lower weatherability. A blending amount exceeding 10 parts by weight
does not improve the weatherability, when compared with that having 10 parts
by weight blended, accordingly such an amount is uneconomical.
Besides these photocurable materials and hindered amine
photostabilizers, a blocked amine compound may be blended to the present
additives, if desired.
Blocked amine compounds employed are those forming primary or
secondary amino group with moisture, without substantial reaction with the
isocyanate group (they may merely be referred to as "blocked amine
compounds", hereinafter). Such blocked amine compounds include aldimines,
ketimines, enamines, oxazolidines, and other condensates of an aldehyde ore
ketone with a compound having at least one primary or secondary amino group
and also having an active hydrogen, such as primary or secondary amino and
hydroxyl groups (hereinafter, referred to as "active hydrogen compound").
Furthermore, compounds having two or more oxazolidine groups in the
molecule, prepared by a reaction of N-hydroxyoxazolidine with an organic
polyisocyanate, are included.
Typical active hydrogen compounds include those having a primary
amino group and hydroxyl group, those having a secondary amino group and
and hydroxyl group, those having a primary amino group, a secondary amino
group and hydroxyl group, those having to primary amino groups, those having
two secondary amino group, and those having a secondary amino group and
two hydroxyl group.
Specifically, the active hydrogen compounds include 2-(2-
aminoethoxy)ethanol, N-(2-aminoethylene)piperazine, ?-hydroxyhexyl-amine, N-
methyl-1,6-hexanediamine, diethylenetriamine, N-(2-hydroxyethyl)ethylene-
diamine, 3-aminoethylpiperazine, N-2(2-hydoxyethyl)piperazine, polyamides
obtained from fatty acids (for example, dimer acid and tall oil acid) and
anhydrous piperazine, 1-amino-3-aminomethyl-3,5,5-trimethyicyclohexane, N-
(methylaminoethyl)-piperazine, aniline, toluidine, xylidine, isophoronediamine,
diaminocyclohexane, diaminodiphenylmethane, xylylenediamine, diamino-
benzene, norbomanedimethylamine (2,5(2,6)-bis(aminomethyl)-bicyclo[2,2,1]-
heptane), diaminomethylbicycloheptane, ethanolamine, diethanoiamine, di-
propanolamine, hexanolamine, Jeffamine D-230, D-400,D-2000 and T-403
(manufactured by Jefferson Chemical, U.S.), ethylenediamine, 1,3-diamino-
propane, tetramethylenediamine, hexamethylenediamine, heptamethylene-
diamine, octamethylenediamine, decamethylenediamine, 4,4"-diaminodicyclo-
hexylmethane, bisaminomethylcyclohexane, 2,5- or 2,6-diaminomethyl-
bicyclo[2,2,1]heptane, 3(4),8(9)-bis(aminomethyl)-tricyclo[5,2,1,0,2,6]decane, di-
aminodiphenylmethane, diaminodiphenyl ether, phenylenediamine, 3,5-
diethyltoluene-2,4- or -2,6-diamine, polyoxyalkylenediamine (obtained by
addition polymerization of propylene oxide and/or ethylene oxide with water,
ethylene glycol, propylene glycol, etc. and conversion of the hydroxyl groups in
the resulting polyoxyalkylene glycol to amino groups), triamines, such as 1,3,5-
tris(aminomethyl)benzene and 1,3,5-tris(aminomethyl)cyclohexane, and poly-
oxyalkylenetriamine (obtained by addition polymerization of propylene oxide
and/or ethylene oxide with glycerol, trimethylolpropane, etc. and conversion of
the hydroxyl groups in the resulting polyoxyalkylenetriol to amino groups).
Aldehydes and ketones to be condensated with the active hydrogen
compounds include, for example, acetaldehyde, propionic aldehyde, butylic
aldehyde, isobutylic aldehyde, trlmethylacetaldehyde, triethylacetaldehyde,
valeric aldehyde, allulolein, crotonic aldehyde, furfural, benzaldehyde, o-
tolualdehyde, m-tolualdehyde, p-tolualdehyde, 4-ethylbenzaldehyde, 4-
propylbenzaldehyde, 4-butylbenzaldehyde, 2,4-dimethylbenzaldehyde, 2,4,6-
trimethylbenzahldehyde, p-anisic aldehyde, p-ethoxybenzaldehyde, acetone,
methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone, diisobutyl ketone,
methylhepatone, cyclohexanone, trimethylcyclohexanone, isophorone,
acetophenone, and the like. Reaction of the active hydrogen compound with an
aldehyde or ketone may be conducted under the well known conditions.
For example, polyaldimine, a kind of the aldimines as mentioned above,
is prepared as follows: a polyamine and an aldehyde are heated together in a
solvent, such as toluene and xylene, in the presence of an acidic catalyst for an
azeotropic dehydration reaction. The reaction is continued until the distillation of
water into a water separator finishes to obtain a polyaldimine. As for the ratio of
polyamine and aldehyde, 1 to 2 equivalent amount of the aldehyde based on 1
equivalent amount of the amine is appropriate. The reaction is generally over
after several hours. After the reaction, the aldehyde and solvent are evaporated
in vacuo from the reaction mixture to leave a polyaldimine.
Such a blocked amine compound forms a primary or secondary amino
group in the presence of moisture. Accordingly, it restrains a direct reaction of
the main component isocyanate with moisture, and the primary or secondary
amino group originated from the blocked amine group readily reacts with the
main component isocyanate, serving for curing of the composition. Since the
curing reaction with the amino group generates no gas, such as carbon dioxide,
the resulting cured products are free from blistering and peeling. Furthermore,
the blocked amine compound reacts with the photocurable material as
mentioned above, to form a film, thus, the weatherable effect of the
photocurable material and accordingly the same effect in the cured product
being enhanced.
Preferable blending amount of the blocked amine compound is 0.1 to
2.0 as the number ratio of the amino group in the hydrolyzed polyamine to the
isocyanate group in polyisocyanate and/or polyurethane prepolymer having the
isocyanate group. A blending ratio of less than 0.1 gives insufficient effect of the
blocked amine compound on the improvement in curability and weatherability. A
ratio exceeding 2.0 provides the formation of excessive amino groups, thus, the
resulting cured composition being softened with a decreased water resistivity.
Additives according to the present invention may desirably further
contain a thixotropy endowing agent. As for the agent, an inorganic filler treated
with an organic material, as well as a polyurea compound, may be suitably used.
These members can be used singly or combinedly.
Thixotropy endowing agent comprising an inorganic filler treated with an
organic material, includes calcium carbonate treated a fatty acid, such as lauric,
stearic, palmitic, oleic and linolic acids; calcium carbonate treated with a metal
salt of a fatty acid, such as calcium palmitate, calcium stearate and sodium
stearate; calcium carbonate treated with a fatty acid ester, such as stearyl
stearate, lauryl stearate, methyl stearate, butyl stearate, stearyl palmitate, lauryl
palmitate and methyl laurate; calcium carbonate treated with a resinic acid, such
as with rosinic and abietic acids; calcium carbonate treated with an organic
titanium compound, such as isopropyltriisosteroyl titanate; calcium carbonate
treated with a surface active agent, such as alkyl benzenesulfonates; calcium
carbonate treated with a polyacrylate; and talc and bentonite treated with an
organic material in similar way as above.
Various thixotropy endowing agent comprising an inorganic filler treated
with an organic material are commercially available. For example, MC Coat S, M
White, Snow Light SSS, EC Series, MS Series, Cal Fine 500 and other Cal Fine
Series from MARUO Calcium K.K.; RAITON Series from BIHOKU FUNKA
KOGYO K.K.; NCC Series and TSS Series from NITTO FUNKA KOGYO K.K.;
GERUTON 50, SL-101, HAKUENKA Series and HOMOKARU Series from
SHIRAISHI K.K., are available.
Thixotropy endowing agent comprising a polyurea compound is a
compound having multiple urea linkages in the molecule and is obtained by a
reaction of polyisocyanate with a monoamine. Thus, the polyurea compound is
represented by the formula:
R1(NHCON-R2, -R3)m
Wherein R1 is a residue originated from polyisocyanate, R2 and R3 are residues
each originated from a monoamine, and one of these residues may be a
hydrogen atom; and m is an integer of 2 to 4; and obtained by a reaction of
polyisocyanate [R1(NCO)m] with a monoamine [R2R3NH], wherein R1, R2, R3 and
m have the same meanings as above.
The polyisocyanate is not limitative and may be any of known aliphatic,
aromatic and alicyclic polyisocyanates. Specifically, it includes straight chain or
branched aliphatic polyisocyanates having 2 to 8 carbon atoms; benzene or
naphthalene polyisocyanates having no substituent or being substituted with a
halogen atom or an alkyl group of 1 to 4 carbon atoms [the isocyanate group
may be linked to the aromatic ring directly or via any crosslinking group (for
example, an alkylene group of 1 to 4 carbon atoms)]; and alicyclic
polyisocyanates of 3 to 6 carbon atoms [the alicyclic group may be substituted
with methyl or other group, and the isocyanate group may be linked to the
cycloalkyl ring directly or via any crosslinking group (for example, an alkylene
group of 1 to 4 carbon atoms)].
More specifically, the polyisocyanate includes toluene 2,4-diisocyanate,
toluene 2,6-diioscyanate, phenylene diisocyanate, xylylene diisocyanate,
diphenylmethane diisocyanate, polyphenylmethane polyisocyanate (Polymeric
MDl), naphtylene 1,5-diisocyanate, triphenylmethane triisocyanate, and diphenyl
sulfone diisocyanate; those hydrogenated compounds, such as 1-methyl-2,4-
diisocyanatocyclohexane, 1-methyl-2,6-diisocyanatocyclohexane, and dicyclo-
hexylmethane diisocyanate; ethylene diisocyanaate, propylene diisocyanate,
tetramethylene diisocyanate, hexamethylene diisocyanate, and isophorone
diisocyanate; a dimer (urethodione diisocyanate) and trimer (isocyanurate
triisocyanate) of these diisocyanates, and the like. These polyisocyanate
compounds may be used singly or combinedly.
Among these polyisocyanates, an arylalkylaryl diisocyanate, such as
diphenylmethane diisocyanate, is particularly preferred from the view point of
thixotropy, production efficiency and costs.
The monoamine is not limitative and may be any of primary and
secondary amines. R2 and R3 are, respectively, hydrogen atom or a group of
aliphatic hydrocarbons, alicyclic hydrocarbons or aromatic hydrocarbons which
may be substituted, provided that R2 and R3 are never hydrogen atom
simultaneously.
Specifically, R2 and R3 may be respectively, a hydrogen atom: a straight
chain or branched, saturated or unsaturated aliphatic hydrocarbon group of 1 to
8 carbon atoms; an alicycllc group of 3 to 6 carbon atoms which may be
substituted with an alkyl group of 1 to 4 carbon atoms; a benzene of naphtha-
lene ring which may be substituted with a halogen atom or with an alkyl group of
1 to 4 carbon atoms; and aryl-substituted alkyl group of 1 to 4 carbon atoms;
provided also that R2 and R3 are never be hydrogen atom simultaneously.
More specifically, they may be, respectively an aliphatic primary amine,
such as methylamine, ethylamine, propylamine, isopropylamine, butylamine,
amylamine, and hexylamine; an aliphatic secondary armine, such as
dimethylamine, diethylamine, dipropylamine, diisopropylamine, and
dibutylamine; an aliphatic unsaturated amine, such as allylamine and
diallylamine; an aiicyclic amine, such as cyclopropylamine, cyclobutylamine,
cyclopentylamine, and cyclohexylamine, and an aromatic amine, such as
aniline, diphenylamine, methylaniline, ethylaniline, toludine, xylidine,
benzylamine, naphthylamine, and the like. The monoamine used in the present
invention is preferably a monoalkylamine, more preferably a straight chain
alkylamine, among which n-butylamine is the most preferable, from the view
points of thixotropy, production efficiency and costs.
Reaction conditions for the polyisocyanate and monoamine are not
limitative. For example, the polyisocyanate and monoamine are subjected to a
reaction under conventional conditions, by dissolving or dispersing in an ester
plasticizer, which is inert to isocyanate, in a ratio of 1.0 to 1.1 (isocyanate group
/ amino or imino group), thereby to obtain a polyurea compound having multiple
urea likages in the molecule, i.e. thixotropy endowing agent according to the
present invention.
The ester plasticizer includes, for example, phthalate esters, adipate
esters, azelainate esters, sebacate esters, sulfonate ester, trimellitate esters,
phosphate esters, fumarate esters, maleate esters, and the like.
Specifically the phthalate esters include diisodecyl phthalate, dioctyl
phthalate, 2-ethylhexyl phthalate, diisononyl phtalate, dibutyl phthalate, butyl
benzyl phthalate, diheptyl phthalate, bis(9\10"-expoxyoctadecyl) 4,5-
epoxyhexahydrophthalate, and the like. The adipate esters include dioctyl
adipate, 2-ethylhexyl adipate, diisononyl adipate, diisodecyl adipate, and the
like. The azelainate esters include di(2-ethylhexyt) azelainate, and the like. The
sebacate esters include di(2-ethylhexyl) sebacate, and the like. The sulfonate
esters include phenyl alkylsulfonates and the like. The trimellitate esters include
tri(2-ethylhexyl) trimellitate and the like. The phosphate esters include triphenyl
phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate,
xylenyl diphenyl phosphate, tris(chloroethyl) phosphate, tris(dichloropropyl)
phosphate, tris(ß-chloropropyl) phosphate, tris(tribromophenyl) phosphate,
tris(dibromophenyl) phosphate, tris(tribromoneopentyl) phosphate, and the like.
The fumarate esters include butyl fumarate, bis(2-methylpropyl) fumarate,
diisobutyl fumarate, bis(2-ethylhexyl) fumarate, and the like. The maleate esters
include dimethyl maleate, diethyl maleate, and the like.
While, the thixotropy endowing agent dispersed in such a plasticizer
constitutes a dispersion paste of the thixotropy endowing agent of the present
invention, as mentioned below.
Since the thixotropy endowing agent comprising such a polyurea
compound is free from water and silanol group, and inert to the polymer
component, such problems as viscosity increase in the composition during the
production or storage step are avoided. Thus, the composition containing such a
polyurea compound has an excellent storage stability, and performs a sufficient
thixotropy at the working execution.
Blending amount of the thixotropy endowing agent per the amount of the
main component (for example, a prepolymer having an isocyanate group at the
terminals) varies depending on the cases where a thixotropy endowing agent
comprising an inorganic filler treated with an organic material and that
comprising a polyurea compound are used combinedly or singly. In a case of
using merely a thixotropy endowing agent comprising an inorganic filler treated
with an organic material, an amount of 50 to 300 parts by weight is preferable,
based on 100 parts by weight of the main component. An amount less that 50
parts by weight gives insufficient thixotropy in the resulting composition, with
unsatisfactory coating and filling workabilities. An amount exceeding 300 parts
by weight causes inferior storage stability, with unsatisfactory coating and filling
workabilities.
In a case of using a thixotropy endowing agent comprising a polyurea
compound, an amount of 10 to 200 parts by weight is preferable, based on 100
parts by weight of the main component. An amount less than 10 parts by weight
gives insufficient thixotropy in the resulting composition, with unsatisfactory
coating and filling workabilities, similarly as in the above inorganic filler. An
amount exceeding 200 parts by weight causes inferior coating and filling
workabilities.
Besides the additives as mentioned above, the highly weatherable,
moisture-curable, one-component polyurethane composition according to the
present invention may contain other additives, fillers, plasticizers, solvents, and
other conventionally used components, so far as they are consistent with the
objectives of the invention.
The fillers mentioned above include calcium carbonate, titanium oxide,
clay, talc, zinc oxide, glass balloon, carbon black, polyamide, PVC, and the like.
The plasticizer includes, for example, phthalate esters, adipate esters,
azelainate esters, sebacate esters, sulfonate esters, trimellitate esters,
phosphate esters, fumurate esters, maleate esters, and the like.
Specifically, the phthalate esters include diisodecyl phthalate, dioctyl
phthalate, 2-ethylhexyl phthalate, diisononyl phthalate, dibutyl phthalate,
butylbenzyl phthalate, diheptyl phthalate, bis(9",10"-epoxyoctadecyl) 4,5-
epoxyhexahydrophthalate, and the like. The adipate esters include dioctyl
adipate, 2-ethylhexyl adipate, diisononyl adipate, diisodecyl adipate, and the
like. The azelainate esters include di(2-ethylhexyl) azelainate, and the like. The
sebacate esters include di(2-ethylhexyl) sebacate, and the like. The sulfonate
esters include phenyl alkylsulfonates and the like. The trimellitate estes include
tri(2-ethylhexyl)trimellitate and the like. The phosphate esters include triphenyl
phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate,
xylenyl diphenyl phosphate, tris(chloroethyl) phosphate, tris(dichloropropyl)
phosphate, tris(ß-chloropropyl) phosphate, tris(tribromophenyl) phosphate,
tris(dibromophenyl) phosphate, tris(tribromopentyl) phosphate, and the like. The
fumarate esters include butyl fumarate, bis(2-methylpropyl) fumarate, diisobutyl
fumarate, bis(2-ethylhexyl) fumarate and the like. The maleate esters include
dimethyl maleate, diethyl maleate, and the like.
Besides these additives as mentioned above, there may be blended a
curing catalyst, such as organic tin catalysts, amine catalysts and organic and
acid catalysts (for example, methylhexahydromaleic adld anhydride [Trade
name: Hardener HY 1102 BD (manufactured by Ciba-Geigy AG], or [Trade
name: RIKACID MH700 (manufactured by SHIN NIPPON RIKA K.K.)]
pyromellitic adid, barbituric acid, etc.) adhesiveness agent [for example, 3-
glycidyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane/burette-
type HDI adduct, polyisocyanate [Trade name: SUMIDUR E21-1, E21-2, L75,
N75, and N3300, DESMODUR RFE, DESMOSEAL M100 (manufactured by
Sumitomo-Bayer Urethane K.K.], [Trade name: BESTANET T-1890 L
(manufactured by DEGUSSA HUELLS K.K.) etc.], antioxidants, UV absorbers,
organic pigments, and the like.
Highly weatherable, moisture-curable, one-component polyurethane
compositions of the present invention are prepared according to any
conventional method, for example, under the environment wherein moisture is
eliminated as far as possible, for example, under a diminished pressure.
Specifically, a polymer component of the invention (the main component
forming a polyurea resin upon curing) is mixed with a photocurable material and
a hindered amine photostabilizer and, if desired, with a blocked amine
compound and thixotropy endowing agent, in a batch-type double axes
kneading mixer. If necessary, the mixture is then blended with a filler, plasticizer
and other additives than the above, and further kneaded and defoamed, thereby
to obtain the objective composition.
The photocurable material additive in the present moisture-curable, one-
component polyurethane composition forms a film at the surface of the cured
product. The hindered amine photostabilizer additive in the present composition
absorbs UV, thus serving for the high weatherability in the cured product. Also,
use of the ordinary prepolymer in the main component allows lower production
costs as compared with those using a polyester prepolymer and the moisture-
curable, modified silicone one-component compositions.
The blocked amine compound additive gives a sufficient curability to the
composition, and excludes such problems as blistering and peeling in the cured
product. Furthermore, the blocked amine compound reacts with the
photocurable material to form a film. Thus, the weatherable effect of the
photocurable material is enhanced, so that the weatherability of the cured
composition is more improved.
The thixotropy endowing agent comprising the polyurea compound
effectively gives excellent storage stability and thixotropy in the resulting cured
composition. Thus, the agent serves for the storage stability, as well as coating
and filling workabilities, of the composition, when used as sealants, inner and
outer use adhesives, and waterproofing materials for roofs and wall surfaces.
Examples
The present invention will more fully be described in reference to the
working examples, as well as the comparative examples for comparison. "Part"
in the examples means part by weight, unless otherwise identified.
"Synthesis of thixotropy endowing agent dispersed paste (A)"
An isocyanate solution made by dissolving 80 parts of diphenylmethane
diisocyanate in 235 parts of diisodecyl phthalate, and an amine solution made
by dissolving 40 parts of n-butylamine in 275 parts of diisodecyl phthalate, were
introduced into a reaction vessel through each separated quantitative pump in
each equivalent amount. The mixture was stirred by means of a static mixer for
the reaction, thereby a dispersed paste of a thixotropy endowing agent having
multiple urea linkages in the molecule, i.e. thixotropy endowing agent dispersed
paste (A) of the invention, being obtained.
"Preparation of the highly weatherable, moisture-curable, one-
component polyurethane composition"
Example 1
Into a batch-type reaction vessel provided with a double axes kneading
mixer were sequentially introduced 150 parts of a prepolymer having a principal
chain skeleton of polypropylene oxide and isocyanate group (particularly
isocyanate group originated from TDI) at the terminals, and 135 parts of the
thixotropy endowing agent dispersed paste (A) as mentioned above [about 26
parts of the solid polyurea compound, when excluding the diisodecyl phthalate
from the dispersed paste (A), at room temparatures. Additionally, 135 parts of
calcium carbonate, 30 parts of titanium oxide, 75 parts of powdered PVC, 3
parts of calcium oxide, 120 parts of isodecyl phthaiate, 9 parts of
TMPMA(trimethylolpropane trimethacrylate) or ARONIX M-80602m
(manufactured by TOA GOSEJ KAGAKU KOGYO K.K.) which was a
photocurable material comprising an unsaturated acrylic compound, 2 parts of a
hindered amine photostabilizer comprising ADEKASTAB LA-62 (manufactured
by ASAHI DENKA K.K.) 2 parts of 3-glycidyloxypropytrimethoxysilane, 0.6 part
of dibutyltin dilaurate (DBTDL), 6 parts of an adhesiveness agent (Trade name:
SUMIDUR E 21-2 [manufactured by Sumitomo Bayer Urethane K.K.]), 27 parts
of xylene, and 10 parts of Solvent A, were added to the reaction vessel.
The mixture was kneaded under stirring in vacuo and then defoamed,
thereby to obtain a highly weatherable, moisture-curable, one-component
polyurethane composition.
Example 2
Similar procedure as in Example 1 was repeated, except that additional
7 parts of a blocked amine compound comprising ALDIMIN ALD-1
(manufactured by MISTUI Chemical K.K.) was added and, in place of the
dibutyltin dilaurate (DBTDL), 0.6 part of methylhexahydrophtaiic acid anhydride
(Trade name: Hardner HY 1102 BD [manufactured by Ciba-Geigy AG] or
RIKACID MH700 [manufactured by SHIN NIPPON RIKA K.K.]) was added,
thereby to obtain a highly weatherable, moisture-curable, one-component
polyurethane composition.
Example 3
Similar procedure as in Example 1 was repeated, except that, in place of
the thixotropy endowing agent dispersed paste (A), 270 parts of CALFAMIN 500
(Trade name [manufactured by MARUO Calcium K.K.]) was added; addition of
the calcium carbonate was omitted; and, in place of the dibutyltin dilaurate
(DBTDL), 0.6 part of methylhexahydrophthalic acid anhydride (Trade name:
Hardner HY 1102 BD) [manufactured by Ciba-Geigy AG] or RIKACID MH 700
[SHIN NIPPON RIKA K.K.]) was added, to obtain a highly weatherable,
moisture-curable, one-component polyurethane composition.
Comparative Example 1
Similar procedure as in Example 2 was repeated, except that addition of
the TMPMA (trimethylolpropane trimethacrylate) or ARONIX M-8060
(manufactured by TOA GOSEI KAGAKU KOGYO K.K.) which was a
photocurable material comprising an unsaturated acrylic compound was omitted,
to obtain a moisture-curable, one-component polyurethane composition.
Comparative Example 2
Similar procedure as in Example 2 was repeated, except that addition of
the hindered amine photostabilizer comprising ADEKASTAB LA-62
(manufactured by ASAHI DENKA K.K.) was omitted, to obtain a moisture-
curable one-component polyurethane composition.
Comparative Example 3
Similar procedure as in Example 2 was repeated, except that addition of
the TMPMA (trimethylolpropane trimethacrylate) or ARONIX M-8060
(manufactured by TOA GOSEI KAGAKU KOGYO K.K.) which was a
photocurable material comprising an unsaturated acrylic compound, and the
hindered amine photostabilizer comprising ADEKASTAB LA-62 (manufactured
by ASAHI DENKA K.K.) was omitted, to obtain a moisture-curable, one-
component polyurethane composition.
The compositions obtainded in Examples 1 to 3 and Comparative
Examples 1 to 3 were evaluated as follows. Results from Examples 1 to 3 and
from Comparative Examples 1 to 3 are shown in Tables 1 and 2, respectively.
(1)Extrudability
Extrudabllities were estimated according to JIS-A-5758-1992 "Sealants
for Architectural Use", "4.2 Extrudability".
Thus, each sample composition just after the preparation was filled in a
cartridge made of a high density polyethylene, without inclusion of foams, and
the cartridge is readily loaded on an air gun. Each sample composition was
extruded from the end of air gun having no nozzle with a pressure of 98.0 kPa at
a temperature of 20°C, and the period of time until the whole of the sample
composition was extruded out of the cartridge was measured. In this test, a
shorter period of time for extrusion shows better extrudability of the composition.
(2) Storage stability
Each test composition was filled in a cartridge as used in the above
"extrudability test", and the closed cartridge was stood at a temperature of 20°C
under a condition of 55% to 65% relative humidity for one month. Thereafter, the
period of time for extrusion of the whole amount of the testing composition out of
the cartridge was measured in similar way as in the above "extrudability" test,
thereby to estimate the storage ability. In this test, a shorter period of time for
extrusion shows better storage stability of the composition.
(3) Thixotropy (slumping test)
Thixotropies were estimated according to JIS-A-5758-1992 "Sealants for
Architectural Use", "4.3 Slumping Tests".
Thus, three of channeled vessels for slumping tests (made of a
corrosion resistive metal, about 1 mm thickness) were provided. Each testing
composition was readily filled in each vessel, avoiding the formation of foams,
and the surface of the testing composition was smoothed. Then, the testing
composition was readily allowed to suspend perpendicularly for 6 hours in a
50°C thermostat. Thereafter, the length from the bottom of the channels in the
vessel to the end of point of the hanging down composition was measured (mm)
for slump (vertical) value. The estimations were made both of just after and one
month after the preperations.
Lower the slump value of the testing composition, better the thixotropy.
A slump value exceeding 2 mm may be said not to have enough thixtropy.
(4) Weathering tests
Weatherabilities were estimated according to JIS-A-1415-1977
"Accelerated weathering test method for plastic architectural materials".
Thus, each sample composition was cured to form a sheet of about 3
mm thickness, which was then subjected to a weathering test using a sunshine
weather meter (manufactured by SUGA SHIKENKI K.K.) for estimation of the
surface weatherability.
As shown in Table 1, the cured product from the composition in Example
1 shows cracks after a 1500 hour accelerated weathering test, but it is
recognized that if s weatherability is still high enough, when compared with the
results in Comparative Examples 1 to 3. The cured product from the composition
in Example 2 wherein a blocked amine compound comprising ALDIMIN ALD-1 is
added shows no crack after a 3000 hour accelerated weathering test, thus, a
significantly high weatherability being identified.
In the cured product from the composition in Example 3, wherein the
thixotropy endowing agent used is an inorganic filler treated with an organic
material, in place of the polyurea compound, cracks are observed after a 2000
hour accerelated weathering test. This fact shows that the weatherability is
inferior to that in Example 2 wherein the thixotropy endowing agent is a polyurea
compound, even though the weatherability is still enough when compared with
those in Comperative Examples 1 to 3. In other words, the thixotropy endowing
agent comprising a polyurea compound gives more advantageous effect on
weatherability than that comprising an inorganic filler treated with an organic
material. Furthermore, the products in Examples 1 and 2 are identified to be
excellent in the extrudability and slump value, thus, also in the thixotropy, as well
as in the storage stability, while, the product from Example 3 is inferior in the
storage stability to that in Examples 1 and 2. Accordingly, thixotropy endowing
agent comprising polyurea compound gives advantageous effect on the storage
stability when compared to that comprising an inorganic filler treated with an
organic material.

On the other side, products from Comparative Examples 1 to 3 form
cracks during 1200 hours, thus, it is identified that they are inferior in the
weatherability to those In Examples 1 to 3.
As described herein before, the highly weatherabie, moisture-curable,
one-component polyurethane compositions of the present invention contain a
photocurable material and hindered amin photostabilizer as the additives. Thus,
the film forming activity of the photocurable material at the surface of the cured
product, and the UV absorbing effect of the hindered amine photostabilizer, serve
for the high weatherability in the cured products. Besides, use of an ordinary
prepolymer as the main component serves for the lower production cost, when
compared with the case of using a polyester prepolymer and moisture-curable,
modified silicone one-component compositions.
Use of a blocked amine compound as the additives gives sufficient
curability to the composition, and eliminates such problems as blistering and
peeling in the cured product, without foaming. Since the blocked amine
compound reacts with the photocurable material mentioned above to form a film,
the compound enhances the weatherabie effect of the photocurable material,
thus the weatherability of the cured product from the present composition being
much increased.
Use of a thixotropy endowing agent comprising a polyuera compound as
the additives serves for effects on the storage stability and thixotropy, so that the
resulting composition possesses an excellent storage stability and thixotropy.
The present composition exhibits excellent storage stability, as well as
the coating and filling workabilities, when used as sealants, inner and outer use
adhesives, and waterproofing materials for roofs and wall surfaces. For example,
when a sealant comprising the present composition is applied or filled on a
vertical surface, the material steadily stays there and is cured at the sealing
places without flowing down, thus, performing the excellent water-tight and air-
tight effects. Moreover, when a sealant comprising the present composition is
applied for sealing between material parts, it functions as a cushion material or
buffer material for the expand and contract, vibration and deformation between
the material parts.
WE CLAIM:
1. A highly weatherable, moisture-curable, one-
component polyurethane composition, which is
characterized by being curable with moisture in the
air, and containing a main component, which will
form a polyurethane resin upon curing, and
additives, wherein said additives comprise one or
more photocurable materials selected from the group
consisting of unsaturated acrylic compounds,
polyvinyl cinnamate and azide-containing compounds,
and a hindered amine photostabilizer.
2. The highly weatherable, moisture-curable, one-
component polyurethane composition as claimed in
Claim 1, wherein said additives additionally contain
a blocked amine compound which will form a primary
or secondary amino group with moisture.
3. The highly weatherable, moisture-curable, one-
component polyurethane composition as claimed in
Claim 1 or 2, wherein said photocurable material is
an unsaturated acrylic compound.
4. The highly weatherable, moisture-curable, one-
component polyurethane composition as claimed in
Claim 1 or 2 or 3, wherein said additives further
contain a thixotropy endowing agent, comprising an
inorganic filler treated with an organic material
selected from the group consisting of fatty acids,
metal salts of fatty acids, fatty acid esters,
resinic acids, surface agents and polyacrylates.
5. The highly weatherable, moisture-curable, one
component polyurethane composition as claimed in
Claim 2 or 2 or 3, wherein said additives further
contain a thixotropy endowing agent, comprising a
polyurea compound represented by the formula:
R1 (NHCON-R2-R3)m
Wherein R1 is a residue originated from
polyisocyanate; R2 and R3 are residues each
originated from a monoamine, and one of these
residues may be hydrogen atom; and m is an integer
of 2 to 4.
6. The highly weatherable, moisture-curable, one
component polyurethane composition as claimed in
Claim 5, wherein said thioxotropy endowing agent
comprising a polyurea compound is added to the
composition in the form of a paste formed by
dispersing the agent in a phathalate ester compound.
A highly weatherable, moisture-curable, one-component
polyurethane composition, which is characterized by being
curable with moisture in the air, and containing a main
component, which will form a polyurethane resin upon
curing, and additives, wherein said additives comprise
one or more photocurable materials selected from the
group consisting of unsaturated acrylic compounds,
polyvinyl cinnamate and azide-containing compounds, and a
hindered amine photostabilizer.

Documents:

00555-kolnp-2003-abstract.pdf

00555-kolnp-2003-claims.pdf

00555-kolnp-2003-correspondence.pdf

00555-kolnp-2003-description (complete).pdf

00555-kolnp-2003-form 1.pdf

00555-kolnp-2003-form 18.pdf

00555-kolnp-2003-form 2.pdf

00555-kolnp-2003-form 3.pdf

00555-kolnp-2003-form 5.pdf

00555-kolnp-2003-letter patent.pdf

00555-kolnp-2003-priority document.pdf

00555-kolnp-2003-reply first examination report.pdf

00555-kolnp-2003-translated copy of priority document.pdf

555-KOLNP-2003-FORM 27.pdf

555-KOLNP-2003-FORM-27-1.pdf

555-KOLNP-2003-FORM-27.pdf

555-kolnp-2003-granted-abstract.pdf

555-kolnp-2003-granted-claims.pdf

555-kolnp-2003-granted-correspondence.pdf

555-kolnp-2003-granted-description (complete).pdf

555-kolnp-2003-granted-examination report.pdf

555-kolnp-2003-granted-form 1.pdf

555-kolnp-2003-granted-form 18.pdf

555-kolnp-2003-granted-form 2.pdf

555-kolnp-2003-granted-form 3.pdf

555-kolnp-2003-granted-form 5.pdf

555-kolnp-2003-granted-letter patent.pdf

555-kolnp-2003-granted-priority document.pdf

555-kolnp-2003-granted-reply to examination report.pdf

555-kolnp-2003-granted-specification.pdf

555-kolnp-2003-granted-translated copy of priority document.pdf


Patent Number 216885
Indian Patent Application Number 555/KOLNP/2003
PG Journal Number 12/2008
Publication Date 21-Mar-2008
Grant Date 19-Mar-2008
Date of Filing 01-May-2003
Name of Patentee SIKA SCHWEIZ AG
Applicant Address TUFFENWIES 16-22, CH 8064 ZURICH, SWITZERLAND.
Inventors:
# Inventor's Name Inventor's Address
1 SUGIYAMA AKIRA 19 SHINDO, HIRATSUKA CITY, KANAGAWA 254 0017
2 KUNITOMO TAKUYA VERDESTAGE MINAMIRINKAN 309, 2-15-3 RINKAN, YAMATO CITY, KANAGAWA 242 003
PCT International Classification Number C08G 18/10
PCT International Application Number PCT/EP01/14390
PCT International Filing date 2001-12-07
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2000/379381 2000-12-13 Japan