Title of Invention

A PROCESS FOR PRODUCING A FLEECE WITH METALLIC WIRE FILAMENTS AND A FLEECE

Abstract

A process for producing a fleece (1) comprising metallic wire filaments (2), using at least the following steps: a) forming a layer (3) comprising wire filaments (2); b) producing first cohesive connections (4) between at least some of the metallic wire filaments (2) using a first joining process; c) producing second cohesive connections (5) between metallic wire filaments (2) using a second joining process. The invention also describes corresponding fleeces and advantageous possible uses, for example in the treatment of exhaust gas from motor vehicles.

Full Text

- 1 - Joining of metallic wire filaments to form fleeces to produce honeycomb bodies The present invention relates to a process for producing a fleece comprising metallic wire filaments, and to a process for producing a honeycomb body having at least one fleece, and also to a fleece having a multiplicity of metallic wire filaments and a honeycomb body formed therewith. Metallic fiber fleeces are used, for example, as filter material for exhaust gases from stationary and mobile internal combustion engines. They are used in particular to retain particulates (ash, soot, etc.) contained in the exhaust gas, these particulates being at least partially retained by the fiber fleece and being chemically converted, if appropriate using a catalyst. On account of the high thermal and dynamic stresses on the fiber fleeces, in particular in exhaust systems of mobile internal combustion engines of, for example, vehicles, boats, etc., particular demands are imposed on a fiber fleece of this type with regard to their long-term strength; in particular, permanent connection of the fibers to one another is necessary. Fiber fleeces of this type are produced, for example, by welding or by forming sintered connections between the wire filaments. When producing the fleeces, it is necessary to take into account the fact that under certain circumstances they also need to be joined to further components in order ultimately to form an exhaust-gas treatment device. For this purpose, it is on occasion necessary for a specific shape to be imparted to the fiber fleece. However, the desired shaping is impeded by the connections which have been formed between the fibers, and consequently considerable difficulties have arisen in series production with a view to manufacture of - 2 - exhaust-gas treatment units of this type. For example, additional handling tools of special configuration are required, and on account of the poor formability of the smooth fiber fleeces, these tools are also subject to considerable wear. Moreover, there is a risk of the fiber fleece tearing uncontrollably at various locations, in which case under certain circumstances fibers may subsequently become detached in the exhaust system. It is an object of the present invention to at least partially alleviate the technical problems which have been outlined in connection with the prior art. In particular, it is an object to specify a process for producing a metallic fleece which allows simple series production even of exhaust-gas treatment units. Furthermore, it is intended to specify a process for producing a honeycomb body which involves using a metallic fleece which can be subjected to accurate shaping even for series production. Finally, it is also intended to propose a fleece which makes it easy to produce honeycomb bodies and apparatuses for exhaust- gas treatment. These objects are achieved by the process for producing a fleece having the features of patent claim 1, the process for producing a honeycomb body having the features of patent claim 6 and the fleece having the features of patent claim 9. Further advantageous configurations of the invention are described in the dependent patent claims. It should be noted that the features listed individually in the patent claims can be combined with one another in any technologically appropriate way so as to form further configurations of the invention. The process according to the invention for producing a fleece comprising metallic wire filaments comprises at least the following steps: - 3 - a) forming a layer comprising wire filaments; b) producing first cohesive connections between at least some of the metallic wire filaments using a first joining process; c) producing second cohesive connections between metallic wire filaments using a second joining process. A "fleece" is to be understood in particular as meaning a sheet-like structure in which the wire filaments that form the fleece can be arranged in ordered fashion or randomly with respect to one another. Examples of a fleece include woven fabrics, grid structures, knitted fabrics, irregular layers, etc. The fleece may in principle also comprise at least one filler, such as for example other types of fleeces, powders or the like, with the latter ultimately being captively connected to the fleece. The fleece is formed by wire filaments which comprise a corrosion-resistant material which is able to withstand high temperatures. The "wire filament" is a term used to signify in particular an element of elongate length and in particular also encompasses elements in wire form, elements in chip form and similar elements. The metallic wire filaments in particular comprise a material which substantially comprises steel as base material, preferably with high chromium contents (e.g. in a range from 18 to 21% by weight) and/or aluminum contents (e.g. at least 4.5% by weight, in particular at least 5.5% by weight). In principle, aluminized wire filaments can also be used. These metallic wire filaments are preferably designed with a filament length in the range from 0.1 to 50 mm (in particular in a range from 1 to 10 mm) and a filament diameter in the range from 0.01 to 0.1 mm (in particular in a range from 0.02 to 0.05 mm). The weight per unit area of a fleece of this type is preferably in the range from 750 to 1500 g/m2. The porosity of the fleece that is to be produced is preferably in a range - 4 - from 3 0% to 80%, in particular in a range from 45% to 60%. According to step a) , first of all a layer comprising wire filaments is formed. This is to be understood as meaning in particular that the wire filaments are arranged in a loose assembly against and/or on top of one another. For this purpose, the wire filaments (random or oriented) are placed, for example, on a support, so that the wire filaments are in contact with one another. The layer is formed until a desired layer thickness, a specified layer weight and/or a desired porosity is present. The layer therefore represents the starting component for the fleece, without any cohesive connections yet being present between the wire filaments. In step b) , first cohesive connections are produced between at least some of the metallic wire filaments using a first joining process. The first cohesive connections are designed in such a way that the fleece can still be readily shaped, in particular can still be wound helically, wound in a S shape or deformed in a similar way. It is preferable for the majority of the metallic wire filaments to have already been connected to one another by the first joining process, preferably at least 80% of the wire filaments. Furthermore, it is preferable for at least some of the metallic wire filaments to have a plurality of first cohesive connections to adjacent wire filaments, which should be the case in particular for at least 40% of the wire filaments. It is very particularly preferable for step b) to be executed such that cohesive connections with regard to a metallic wire filament are formed only in a subregion of the wire filament which is significantly smaller than the filament length; by way of example, these first cohesive connections are formed only in a subregion amounting to less than 20% (in particular less than 5%) of the filament length. - 5 - With this type of configuration of the first cohesive connections, there is only a relatively small or reduced number of cohesive connections or connection points stiffening the fleece, so that on the one hand it is ensured that the fleece is transportable and even also deformable, but on the other hand the risk of insufficient anchoring or fixing of a significant proportion of the wire filaments is avoided. The first joining process is preferably a joining process selected from the group consisting of manufacturing processes relating to joining by welding and joining by soldering. In principle, it is possible to work with or without filler. Then, in a further step c), second cohesive connections are produced between the metallic wire filaments using a second joining process. In other words, this means in particular that the formation of the first and second cohesive connections takes place locally and temporally separately. During the second joining process, additional second cohesive connections or connection points are generated, which lead to further stiffening of the fleece. In particular, a first flexural strength after step b) (maximum force occurring during bending of the fleece (width: 50 mm) up to a bending angle of 90° with a free bending length of 2 0 mm) is considerably lower than a second flexural strength after step c) has been carried out, the second flexural strength preferably being at least 50%, in particular 100% greater than the first flexural strength. Since the absolute flexural strength value is dependent on the specific configuration of the fleece, it is possible here, purely by way of example (0.3 mm fleece thickness 0.022 mm filament diameter, 85% porosity), to specify a value for the flexural strength. The first flexural strength is in this case in a range from 600 to 12 00 mN and preferably below 1000 mN, whereas after step c) by way of example a second flexural strength of - 6 - at least 1500 mn is produced. After step c) , it is preferable for at least 90% of all the wire filaments to have at least one first and/or at least one second cohesive connection. The process proposed here proposes two-stage generation of the desired fleece property in terms of its structural integrity. This opens up the possibility of the fleece first of all being brought into a readily shapeable state, then being deformed into its final shape and finally acquiring its ultimately desired rigidity in a subsequent joining process. This allows, for example, the production of structured fleeces which are ultimately able to withstand the high dynamic and thermal stresses in the exhaust system of mobile internal combustion engines for a prolonged period of time. Furthermore, it is proposed that a welding process be used as first joining process to carry out step b) . It is very particularly preferable for resistance welding processes to be used to form the first cohesive connections. In this context, what is known as roller seam welding, in which at least two roller-like electrodes are arranged on either side of the fleece, has proven particularly suitable. Applying a voltage to the electrodes and bringing them into contact with the wire filament layer leads to the formation of cohesive connections between the metallic wire filaments. On account of the spatially delimited zone of action of the welding process, first cohesive connections are also generated only in relatively locally limited subregions of the layer or fleece. This allows the desired fleece property to be set in a targeted fashion for further treatment of the fleece. According to a further configuration of the process, it is proposed that a high-temperature treatment of the fleece to form sintered connections be used as second - 7 - joining process to carry out step c). In this case, it is very particularly preferable for the fleece to be exposed to a temperature of over 800°C, in particular over 1100°C. The environment surrounding the fleece can in this case be realized with a vacuum and/or a shielding gas atmosphere. The second cohesive connections are in particular characterized by what are known as sinter necks, which form as a result of surface diffusion between the metallic wire filaments. The second cohesive connections are usually positioned in the region of contact between adjacently fixed wire filaments. According to a further configuration of the process, step b) comprises forming a connection plan, so that at least one anisotropic fleece property is produced. An "anisotropic" configuration of a property is to be understood in particular as meaning that the extent of this property differs significantly as seen in different directions of the fleece. This means, for example, that the fleece after step b) is flexurally rigid in one direction and flexurally yielding in another direction. To achieve this, it is proposed that a connection plan be formed. A "connection plan" is to be understood as meaning a predetermined arrangement of zones of first cohesive connections. This connection plan may comprise a plurality of zones of first cohesive connections arranged in a defined way with respect to one another such that they form a type of pattern. The connection plan can be formed with a plurality of zones, at least some of which are parallel to one another and/or at least some of which cross one another. The specific configuration of the connection plan is dependent mainly on the type of deformation of the fleece which is still desired. The different configuration of the connection plan allows in particular the following fleece properties to be made anisotropic: flexural strength, strength, cold- formability, tensile strength. - 8 - According to a further configuration of the process, at least one of the following steps is carried out between step b) and step c) : transporting the fleece, deforming the fleece, coating the fleece. During transporting of the fleece, the fleece is, for example, removed from a support or moved together with the support to a different location. In this context, it is also possible for the fleece to be at least partially elastically deformed, rotated, etc. The deformation of the fleece comprises, for example, the introduction of openings, winding of the fleece, twisting and/or structuring of the fleece. During the deformation of the fleece, it is preferable to effect a permanent, plastic deformation of the sheet-like structure to form a more complex structure, for example in the manner of a spiral, a cylinder, with a corrugated or zigzag shape, etc. The coating of the fleece may comprise the application of a filler, with this filler being temporarily or permanently fixed to the fleece. A temporary coating could, for example, comprise attaching an adhesive for fixing further components or a powder (solder, filter material, etc.). One example of a permanent coating is the application of any additional material comprising at least one alloying element which is at least partially introduced into the surface of the fleece, if appropriate at the same time as step c) is being carried out. A further aspect of the invention proposes a process for producing a honeycomb body having at least one fleece comprising a multiplicity of metallic wire filaments, which comprises at least the following steps: w) forming a layer of wire filaments; - 9 - x) producing first cohesive connections between at least some of the metallic wire filaments using a first joining process; y) arranging at least one fleece so as to form a honeycomb body; z) producing second cohesive connections between metallic wire filaments using a second joining process. A honeycomb body is characterized in particular by the fact that it is designed with a multiplicity of passages, which are usually arranged substantially parallel to one another and at least some of which a fluid can flow through. Honeycomb bodies of this type are used, for example, to remove pollutants from exhaust gases from mobile internal combustion engines. The honeycomb bodies serve, for example, as supports for a catalytically active coating and/or as a particulate trap. At least one fleece comprising a multiplicity of metallic wire filaments is provided here for building up the honeycomb structure. For details as to the production of the wire filament fleece (steps w) and x) ) , reference should be made to the explanations given above in connection with steps a) and b). After the first cohesive connections have been produced, according to step y) the process step of arranging at least one fleece so as to form a honeycomb body takes place. This arranging step comprises, for example, deforming the fleece, aligning the fleece with respect to further components of the honeycomb body (such as for example additional sheet-metal foils), integrating the fleece in a housing, and the like. It is preferable for step y) to be carried out in such a way that the desired configuration of the honeycomb body having the at least one fleece is present, and finally in step z) the desired long-term strength or rigidity of the fleece or honeycomb body is realized. - 10 - It is in this context particularly advantageous for step y) to encompass the assembly of the at least one fleece with other metallic components, and for cohesive connections also to be formed between at least some of the components during step z) . Further metallic components, which may form part of a honeycomb body, include, for example, a metallic housing, at least one metal foil (which likewise at least partially delimits passages) and metallic connection elements which, for example, allow a plurality of fleeces to be connected to one another and/or close off at least some of the passages in the honeycomb body. In connection with step y) , the intention is in particular the alternate stacking of a smooth fleece and a corrugated metal foil, which are then wound and/or intertwined to form a honeycomb body. This assembly made up of metal foil and fleece is then inserted into a housing, which takes place with a prestress which is such that the assembly made up of fleece and metal foil is temporarily fixed. In this arrangement of the components with respect to one another, second cohesive connections are then formed during step z). It is in this context also advantageous for step z) to comprise a soldering process (specifically what is known as "brazing") carried out at temperatures above 800°C and under vacuum. It is in this context advantageous for at least subregions of the components to be provided with a soldering material, which then forms further cohesive connections between at least some of the components. Therefore, during step z) , on the one hand the fleece is stiffened by the formation of second cohesive connections between the wire filaments, and at the same time a connection is produced between the components. The brazing process described here preferably takes place at temperatures above 1000°C. This process step also improves the quality or strength of the connections. - 11 - A further aspect of the invention proposes a fleece having a multiplicity of metallic wire filaments, some of the wire filaments being cohesively connected to one another according with a connection plan, so that the fleece has at least one anisotropic fleece property. With regard to the anisotropy, reference is made to the explanations given above. The at least one fleece property comprises at least one of the following properties of the fleece: flexural strength, strength, cold-formability, tensile strength. The starting point here is in particular that the wire filaments are arranged randomly with respect to one another. It is in principle possible for the fleece also to be formed using oriented or ordered wire filaments, so that, for example, the arrangement of these filaments already produces an anisotropy. Nevertheless, the preferred option here is a fleece in which the wire filaments are arranged randomly with respect to one another and the anisotropy has been produced by specially formed first cohesive connections. Accordingly, the fleece can be produced in particular by the above process which has been described in accordance with the invention. The invention also proposes a honeycomb body comprising a plurality of passages, the passages at least partially being formed by a fleece of the type described above. In this context, a single fleece is preferably used to delimit a plurality of passages, and in the case of a helical structure of the honeycomb body it is even possible for a single fleece to partially delimit all the passages at least in part. The invention also proposes an apparatus for exhaust- gas treatment, comprising at least one fleece of the type according to the invention, at least one fleece produced by a process according to the invention, or at - 12 - least one honeycomb body of the type mentioned above. The exhaust gas to be purified at least partially flows through this apparatus, with solid particulates at least in part accumulating in or on the fleece. This apparatus is preferably designed as a filter or particulate trap. Therefore, it is particularly advantageous for a vehicle comprising an internal combustion engine to be combined with at least one apparatus of the above type. The vehicle is preferably a truck or passenger car, in which case the apparatus is integrated in its exhaust system. The internal combustion engine is, for example, a spark-ignition engine or a diesel engine. The invention and the technical background are explained in more detail with reference to the figures. The figures also show particularly preferred exemplary embodiments of the invention, although without the invention being restricted to these embodiments. The figures are diagrammatic in form and in general cannot serve to illustrate size ratios. In the figures: Fig. 1 shows a perspective illustration of a first variant embodiment of a fleece; Fig. 2 shows a detail view of the fleece from fig. 1; Fig. 3 shows the sequence of a first fleece production variant; Fig. 4 shows a detail view of a honeycomb body with a fleece; Fig. 5 shows a further variant embodiment of a honeycomb body with a fleece; and - 13 - Fig. 6 shows a vehicle with an exhaust-gas-treatment apparatus. Fig. 1 provides a diagrammatic and perspective illustration of a fleece 1 which is formed by a multiplicity of metallic wire filaments 2. The fleece 1 has first cohesive connections 4, which together form a connection plan 6. In the variant embodiment illustrated, some of the first cohesive connections 4 are formed as a parallel line, in particular a weld seam, this connection plan 6 being crossed by a "zigzag"-like configuration of a further first cohesive connection 4. If the fleece is considered in a state in which second cohesive connections 5 have not yet been generated, the fleece 1 has anisotropic fleece properties. The anisotropy is configured to be different in particular in the direction of the fleece thickness 17 (z direction) or in its plane (x direction and y direction). It is very particularly preferable for an anisotropy to be formed with regard to the x and y directions, so that the fleece 1 is, for example, flexurally yielding in the x direction and flexurally rigid in the y direction. The weld seams illustrated may have a width of up to 100 mm, in which case the distance between the adjacent weld seams may be designed to be smaller than the width of the weld seams. The term weld seam is used to describe a zone with a high number of cohesive connections, in particular compared to the layer or fleece before and after a welding operation. Figure 2 now shows a detail of the fleece from figure 1 at a time when second cohesive connections 5 have been formed. The second cohesive connections 5 are preferably formed as sintered connections which are produced in contact regions of the wire filaments 2. The wire filaments 2 advantageously have a filament length 16 in the range from 1 to 10 mm and a filament diameter 15 in the range from 0.02 to 0.05 mm. On - 14 - account of the random arrangement of the wire filaments 2 with respect to one another, pores 18 are formed, allowing the fleece 1 to be gas-permeable. The porosity of the fleece is in the range from, for example, 45% to 6 0%. After first cohesive connections 4 and second cohesive connections 5 have been formed, the anisotropy which was previously present is greatly reduced or no longer significant. In this context, it should fundamentally be pointed out that the fleece properties relate to the actual fleece and not to its assembly with further components which may influence the rigidity. Fig. 3 illustrates a variant embodiment of the process for producing a fleece 1. Wire filaments 2 are placed by means of a distributor 19 onto a support 3 5 (if appropriate designed as a conveyor belt), so as to form a layer 3 comprising wire filaments 2. When the desired composition of the layer 3 is present, this loose assembly of wire filaments 2 is provided, in a further step, with first cohesive connections by means of a first joining process, so as to generate a fleece 1. In the variant embodiment illustrated, the joining process is carried out by means of a welding installation 20, with the sketched illustration showing a roller seam welding process (resistance welding). After the fleece 1 with anisotropic fleece properties has been formed, it is possible to carry out various further process steps for producing, for example, a honeycomb body, before the second cohesive connections 5 are finally produced in a further process step (illustrated on the right-hand side of fig. 3) . In the illustration, this is done by means of a furnace 21 in which, for example, temperatures of over 1000°C are present, with sintered connections being formed between the wire filaments 2. Fig. 4 illustrates a variant embodiment of a honeycomb body 7 having a fleece 1. The honeycomb body 7 has a multiplicity of passages 11 through which an exhaust - 15 - gas can flow in a direction of flow 23. The passages 11 are delimited on the one hand by a fleece 1 and on the other hand by metal foils 9. The metal foils 9 are in structured form with corrugation peaks 25 and corrugation valleys 26. Flow-influencing means 24, which project into inner regions of the passages 11, are provided for the purpose of influencing the direction of flow 23 of the exhaust gas and/or of the particulates 22 contained therein. Therefore, some of the exhaust gas is diverted toward the fleece 1, with the particulates 22 accumulating at the wire filaments 2 of the fleece 1. A further configuration of a honeycomb body 7 as what is known as a "wall-flow filter" is illustrated in fig. 5. This honeycomb body 7 likewise has a plurality of passages 11 which are closed on alternate sides. The passages 11 in turn are at least partially formed by a fleece 1, it being possible for exhaust gas to enter inner regions of the honeycomb body 7 in a direction of flow 23, and this exhaust gas, as a result of the positioning of connection elements 10 at the end sides 36, being forced to penetrate fully through the fleece 1. To prevent blockages, it is possible to provide openings 27 in the fleece 1, constituting a type of bypass, if the fleeces 1, on account of a high level of accumulated particulates, form an excessively high flow resistance to the exhaust gas. This honeycomb body 7 is arranged in a metallic housing 8 and is preferably soldered to it. Finally, fig. 6 illustrates a preferred intended use of the fleece 1 or the honeycomb body 7. This figure illustrates a motor vehicle 13 having an internal combustion engine 14. The internal combustion engine 14 generates an exhaust gas which is at least partially purified by means of the exhaust system 29 illustrated. For this purpose, the exhaust gas first of all flows through a primary catalytic converter 28. It then flows - 16 - through an oxidation catalytic converter 3 0 and an apparatus 12 for exhaust-gas treatment, which is designed here as a particulate trap 31. The combination of an oxidation catalytic converter 30 and a particulate trap 31, by virtue of the provision of nitrogen oxides, allows continuous regeneration of the particulate trap 31, so that if appropriate it is possible to dispense with thermal regeneration, i.e. burning off of soot constituents. The exhaust gas then also flows to a muffler 32 before leaving the exhaust system 29. - 17 - List of designations 1 Fleece 2 Wire filament 3 Layer 4 First connection 5 Second connection 6 Connection plan 7 Honeycomb body 8 Housing 9 Metal foil 10 Connection element 11 Passage 12 Apparatus 13 Vehicle 14 Internal combustion engine 15 Filament diameter 16 Filament length 17 Fleece thickness 18 Pore 19 Distributor 20 Welding installation 21 Furnace 22 Particulate 23 Direction of flow 24 Flow-influencing means 25 Corrugation peak 26 Corrugation valley 27 Opening 28 Primary catalytic converter 29 Exhaust system 30 Oxidation catalytic converter 31 Particulate trap 32 Muffler 33 Width 34 Distance 35 Support 36 End side - 18 - Patent claims 1. A process for producing a fleece (1) comprising metallic wire filaments (2), using at least the following steps: a) forming a layer (3) comprising wire filaments (2) ; b) producing first cohesive connections (4) between at least some of the metallic wire filaments (2) using a first joining process; c) producing second cohesive connections (5) between metallic wire filaments (2) using a second joining process. 2. The process as claimed in claim 1, in which a welding process is used as first joining process to carry out step b). 3. The process as claimed in claim 1 or 2, in which a high-temperature treatment of the fleece (1) to form sintered connections is used as second joining process to carry out step c). 4. The process as claimed in one of the preceding claims, in which step b) comprises forming a connection plan (6) , so that at least one anisotropic fleece property is produced. 5. The process as claimed in one of the preceding claims, in which at least one of the following steps is carried out between step b) and step c) : transporting the fleece (1) , deforming the fleece (1) , coating the fleece (1). 6. A process for producing a honeycomb body (7) having at least one fleece (1) comprising a multiplicity of metallic wire filaments (2) , which comprises at least the following steps: w) forming a layer (3) of wire filaments (2); - 19 - x) producing first cohesive connections (4) between at least some of the metallic wire filaments (2) using a first joining process; y) arranging at least one fleece (1) so as to form a honeycomb body (7); z) producing second cohesive connections (5) between metallic wire filaments (2) using a second joining process. 7. The process as claimed in claim 6, in which step y) comprises assembling the at least one fleece (1) with other metallic components (8, 9, 10) , and during step z) cohesive connections are formed between at least some of the components (1, 8, 9, 10) . 8. The process as claimed in claim 6 or 7, in which step z) comprises a soldering process carried out at temperatures above 800°C and under vacuum. 9. A fleece (1) having a multiplicity of metallic wire filaments (2) , some of the wire filaments (2) being cohesively connected to one another according to a connection plan (6) , so that the fleece (1) has at least one anisotropic fleece property. 10. The fleece (1) as claimed in claim 9, in which the wire filaments (2) are arranged randomly with respect to one another. 11. A honeycomb body (7) comprising a plurality of passages (11), the passages (11) at least partially being formed by the fleece (1) as claimed in claim 9 or 10. 12. An apparatus (12) for exhaust-gas treatment, comprising at least one fleece (1) as claimed in claim 9 or 10, at least one fleece (1) produced by the process as claimed in one of claims 1 to 8, or at least one honeycomb body (7) as claimed in claim 11. - 20 - 13. A vehicle (13) comprising an internal combustion engine (14) in combination with at least one apparatus (12) as claimed in claim 12. A process for producing a fleece (1) comprising metallic wire filaments (2), using at least the following steps: a) forming a layer (3) comprising wire filaments (2); b) producing first cohesive connections (4) between at least some of the metallic wire filaments (2) using a first joining process; c) producing second cohesive connections (5) between metallic wire filaments (2) using a second joining process. The invention also describes corresponding fleeces and advantageous possible uses, for example in the treatment of exhaust gas from motor vehicles.

Documents:

04666-kolnp-2007-abstract.pdf

04666-kolnp-2007-claims.pdf

04666-kolnp-2007-correspondence others.pdf

04666-kolnp-2007-description complete.pdf

04666-kolnp-2007-drawings.pdf

04666-kolnp-2007-form 1.pdf

04666-kolnp-2007-form 2.pdf

04666-kolnp-2007-form 3.pdf

04666-kolnp-2007-form 5.pdf

04666-kolnp-2007-gpa.pdf

04666-kolnp-2007-international publication.pdf

04666-kolnp-2007-international search report.pdf

04666-kolnp-2007-pct request form.pdf

04666-kolnp-2007-translated copy of priority document.pdf

4666-KOLNP-2007-(15-09-2011)-ABSTRACT.pdf

4666-KOLNP-2007-(15-09-2011)-AMANDED CLAIMS.pdf

4666-KOLNP-2007-(15-09-2011)-DESCRIPTION (COMPLETE).pdf

4666-KOLNP-2007-(15-09-2011)-DRAWINGS.pdf

4666-KOLNP-2007-(15-09-2011)-EXAMINATION REPORT REPLY RECIEVED.PDF

4666-KOLNP-2007-(15-09-2011)-FORM 1.pdf

4666-KOLNP-2007-(15-09-2011)-FORM 2.pdf

4666-KOLNP-2007-(15-09-2011)-FORM 3.pdf

4666-KOLNP-2007-(15-09-2011)-OTHERS.pdf

4666-KOLNP-2007-(15-09-2011)-PETITION UNDER RULE 137.pdf

4666-KOLNP-2007-CORRESPONDENCE OTHERS 1.1.pdf

4666-KOLNP-2007-CORRESPONDENCE OTHERS 1.2.pdf

4666-KOLNP-2007-OTHERS.pdf

4666-KOLNP-2007-PCT REQUEST 1.1.pdf

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