Mat material, exhaust gas purification device, and method for manufacturing mat material

Abstract

The mat material is characterized in that a network is formed on at least one of a first main surface and a second main surface of a base mat comprising inorganic fibers and having the first main surface and the second main surface by a plurality of bases comprising an organic material and fibers extending from each of the plurality of bases in at least two directions.

Description

Technical Field

[0001] The invention relates to a mat material, an exhaust gas purification device and a method for manufacturing the mat material. Background Art

[0002] Exhaust gas discharged from internal combustion engines such as diesel engines contains particulate matter (hereinafter also referred to as PM), and in recent years, the PM has become a problem of harming the environment and human body. In addition, since the exhaust gas also contains harmful gas components such as CO, HC, and NOx, there is also concern that these harmful gas components will affect the environment and human body.

[0003] Therefore, as an exhaust gas purification device for capturing PM in exhaust gas and purifying harmful gas components, various schemes of exhaust gas purification devices have been proposed, which are composed of an exhaust gas treatment body (which is composed of porous ceramics such as silicon carbide and cordierite), a shell (cylindrical member) for accommodating the exhaust gas treatment body, and a holding sealing material arranged between the exhaust gas treatment body and the shell. The main purpose of arranging the holding sealing material is to prevent the exhaust gas treatment body from contacting with the shell covering its outer periphery and being damaged due to vibration or impact caused by the driving of the car, etc.; to prevent exhaust gas from leaking from between the exhaust gas treatment body and the shell; etc.

[0004] As a holding sealing material used in such applications, a mat material composed of inorganic fibers is used. A mat material composed of inorganic fibers is also used for heat insulation and sound insulation purposes when it is wound around a pipe of an automobile or the like.

[0005] Patent document 1 discloses a holding sealing material, wherein a sheet having an opening in at least a portion of its surface is provided on at least one of a first main surface and a second main surface of a base material. In addition, it is disclosed that a sheet made of a heat-fusible material is thermally pressed onto the base material, thereby adhering the sheet to the main surface of the base material without using an adhesive.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2009-85092 Summary of the invention

[0009] Problems to be solved by the invention

[0010] In Patent Document 1, a sheet is provided in order to prevent the inorganic fibers contained in the base material from scattering.

[0011] As a method for producing such a mat material, a method of punching using a punching die having a punching blade (also referred to as a punching process) has been conventionally used.

[0012] In this step, a sheet-like member composed of inorganic fibers and a large-sized attached body to which a flexible sheet is attached are prepared, and the attached body is punched out, whereby a large number of mat materials can be obtained by a single punching process.

[0013] The mat has a long side direction as a winding direction and a short side direction orthogonal to the long side direction.

[0014] When such a mat material is obtained from a large-sized attached body, the parts where the mat material is punched out in the longitudinal direction of the attached body as the long side direction of the mat material and the parts where the mat material is punched out in the transverse direction of the attached body as the long side direction of the mat material are combined to obtain as much mat material as possible from the large-sized attached body.

[0015] In this case, two types of mat materials having different orientation relationships between the longitudinal and transverse directions of the attached body and the long side direction of the mat material can be obtained.

[0016] In addition, in Patent Document 1, the sheet is adhered to the base material by heat pressing, but at this time, the fibers forming the sheet are melted and attached to the base material. Therefore, it is believed that the fiber openings of the sheet after heat pressing reduce the fiber strength. In addition, it is believed that the softness of the sheet is weakened by the mutual fusion of multiple fibers of the sheet. As a result, when the mat material provided with the sheet is wound on an exhaust gas treatment body, etc., the mat material may crack.

[0017] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a mat material capable of suppressing the occurrence of cracks during winding.

[0018] Means for solving problems

[0019] The first embodiment of the mat material of the present invention is characterized in that, on at least one of the first main surface and the second main surface of a base material mat comprising inorganic fibers and having a first main surface and a second main surface, a network is formed by a plurality of bases composed of organic matter and fibers extending from the plurality of bases in at least two directions, respectively.

[0020] The first embodiment of the mat material of the present invention forms a network on at least one of the first main surface and the second main surface of the base material pad through multiple bases composed of organic matter and fibers extending from the multiple bases in at least two directions, so it has high strength and flexibility, thereby being able to suppress the occurrence of cracks when the mat material is wound.

[0021] In the mat material according to the first aspect of the present invention, it is preferred that the maximum width of each of the plurality of base portions is larger than the width of the fibers forming the network.

[0022] As a result, the fibers forming the network can be more tightly bonded to each other, thereby further improving the strength of the entire mat. As a result, the occurrence of cracks when the mat is wound can be more effectively suppressed.

[0023] In the mat material according to the first aspect of the present invention, it is preferred that the glass transition temperature of the fibers forming the network be higher than the glass transition temperature of the organic substance constituting the plurality of bases.

[0024] Thereby, the above-mentioned network can be easily formed using hot-melt powder.

[0025] In the mat material according to the first aspect of the present invention, it is preferred that the network is formed three-dimensionally.

[0026] This can improve the strength of the network formed on the first main surface and / or the second main surface of the base mat, and can disperse the stress applied to the network, thereby more effectively suppressing the occurrence of cracks when the mat is wound.

[0027] In the mat material according to the first aspect of the present invention, it is more preferable that the fibers forming the network are composed of at least one of organic fibers and inorganic fibers.

[0028] From the viewpoint of more effectively suppressing the occurrence of cracks when the mat is wound, the fibers forming the network are more preferably composed of organic fibers.

[0029] The second aspect of the mat material of the present invention is characterized in that on at least one of the first and second main surfaces of a base mat including inorganic fibers and having a first and second main surfaces, a fiber bundle and single fibers formed by interweaving a plurality of fibers form a network.

[0030] In the mat material of the second embodiment of the present invention, the mesh material includes a fiber bundle, but the fiber bundle is formed by interweaving a plurality of fibers, and further, the mesh material is formed by such fiber bundles and short fibers, so that the strength and flexibility of the fibers forming the mesh material can be suppressed from being reduced. As a result, the generation of cracks when the mat material is wound can be suppressed.

[0031] The mat material according to the second aspect of the present invention preferably includes a plurality of the fiber bundles having different extending directions from each other, and the web is preferably formed by the plurality of the fiber bundles and the single fibers.

[0032] Thereby, the number of fibers of the longitudinally oriented fibers and the number of fibers of the transversely oriented fibers can be made equal.

[0033] In the mat material according to the second aspect of the present invention, it is preferred that at least one of the fiber bundle and the single fiber is bent.

[0034] This increases the number of intersections between the fibers forming the web, and makes it possible to disperse the stress applied to the web, thereby more effectively suppressing the occurrence of cracks when the mat is wound.

[0035] In the mat material according to the second aspect of the present invention, it is preferable that the mesh is formed three-dimensionally.

[0036] This can improve the strength of the mesh formed on the first main surface and / or the second main surface of the base mat, and can disperse the stress applied to the mesh, thereby more effectively suppressing the occurrence of cracks when the mat is wound.

[0037] In the mat material according to the second aspect of the present invention, it is more preferable that the fiber bundle and the single fiber each consist of at least one of organic fibers and inorganic fibers.

[0038] From the viewpoint of more effectively suppressing the occurrence of cracks when the mat is wound, the fiber bundle and the single fiber are more preferably each composed of organic fibers.

[0039] The exhaust gas purification device of the present invention comprises: an exhaust gas treatment body, which is used for exhaust gas circulation; a retaining sealing material, which is wound around the outer periphery of the above-mentioned exhaust gas treatment body; and an outer shell, which accommodates the above-mentioned exhaust gas treatment body wound with the above-mentioned retaining sealing material. The exhaust gas purification device is characterized in that the above-mentioned retaining sealing material is a mat material of the first or second mode of the present invention.

[0040] As described above, the mats of the first and second aspects of the present invention can suppress the generation of cracks during winding. Therefore, the exhaust gas purifying device of the present invention can suppress the leakage of untreated exhaust gas from the cracks of the mat.

[0041] The manufacturing method of the mat material of the present invention is characterized in that it comprises: a base mat preparation step, preparing a base mat containing inorganic fibers and having a first main surface and a second main surface; a sheet material preparation step, preparing a sheet material containing fibers extending in at least two directions; a sheet material processing step, spreading hot-melt powder on the above-mentioned sheet material and heating it to make the above-mentioned hot-melt powder adhere to the above-mentioned sheet material; and a sheet material attaching step, hot-pressing the above-mentioned sheet material to which the above-mentioned hot-melt powder is attached to at least one of the above-mentioned first main surface and the second main surface of the above-mentioned base mat, and attaching the above-mentioned sheet material to the above-mentioned base mat.

[0042] In the manufacturing method of the mat material of the present invention, hot-melt powder is spread on a sheet material containing fibers extending in at least two directions and heated, so that the hot-melt powder is attached to the sheet material, the sheet material attached with the hot-melt powder is hot-pressed to at least one of the first main surface and the second main surface of the substrate pad, and the sheet material is attached to the substrate pad, so that the sheet material can be attached to the substrate pad while preventing the fibers forming the sheet material from melting. Therefore, the strength and flexibility of the fibers forming the sheet material can be suppressed from being reduced. In addition, by heating and melting the hot-melt powder, a network with a base can be formed. As a result, cracks can be suppressed from occurring when the mat material is wound. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a perspective view schematically showing an example of the mat material according to the first aspect of the present invention.

[0044] Figure 2 It is schematically shown Figure 1 A magnified top view of the network is shown.

[0045] Figure 3 It is a perspective view schematically showing an example of an attached body.

[0046] Figure 4 It is a plan view schematically showing an example of a process of obtaining two types of mat materials by punching.

[0047] Figure 5 It is a perspective view schematically showing an example of a mat material according to a second aspect of the present invention.

[0048] Figure 6 It is schematically shown Figure 5 An enlarged top view of the mesh is shown.

[0049] Figure 7 It is a perspective view schematically showing another example of an attached body.

[0050] Figure 8 It is a plan view schematically showing another example of the process of obtaining two types of mat materials by punching.

[0051] Fig. 9 This is a cross-sectional view schematically showing an example of the exhaust gas purification device of the present invention.

[0052] Fig.10 This is a photograph of the mat of Comparative Example 1. DETAILED DESCRIPTION

[0053] The following is a detailed description of the mat material, the exhaust gas purification device, and the method for manufacturing the mat material of the present invention. However, the present invention is not limited to the following configurations, and can be appropriately changed for application without changing the gist of the present invention. It should be noted that a combination of two or more of the preferred configurations of the present invention described below is also the present invention.

[0054] The first embodiment of the mat material of the present invention is characterized in that, on at least one of the first main surface and the second main surface of a base material mat comprising inorganic fibers and having a first main surface and a second main surface, a network is formed by a plurality of bases composed of organic matter and fibers extending from the plurality of bases in at least two directions, respectively.

[0055] Figure 1 It is a perspective view schematically showing an example of the mat material according to the first aspect of the present invention.

[0056] Figure 1 The mat material 10 shown has the following structure: on the first main surface 21 of the base material mat 20 having the first main surface 21 and the second main surface 22, a base part and fibers (both on the first main surface 21 and the second main surface 22) are formed. Figure 1 A network 70 is formed by (not shown in the figure).

[0057] On the long side of the mat 10 ( Figure 1 A convex portion 11 is formed at one of the ends (in the direction indicated by the double arrow L), that is, a first end, and a concave portion 12 is formed at the other end, that is, a second end.

[0058] The convex portion 11 and the concave portion 12 are formed by overlapping convex portions and concave portions provided on the base material pad 20 and the network 70 , respectively.

[0059] The convex and concave portions of the mat material are shaped so as to fit into each other when the mat material is wound around an exhaust gas purifying device, an exhaust gas treating body, or an exhaust pipe having a cylindrical outer circumference.

[0060] It should be noted that in Figure 1 , the direction indicated by the double arrow W is the short side direction of the mat material, and the direction indicated by the double arrow T is the thickness direction of the mat material.

[0061] It should be noted that Figure 1 2 shows a case where the network 70 is formed only on the first main surface 21 of the substrate pad 20, but the network 70 may be formed on each of the first main surface 21 and the second main surface 22 of the substrate pad 20. In addition, in addition to the first main surface 21 and / or the second main surface 22 of the substrate pad 20, the network 70 may also be formed on the side of the substrate pad 20.

[0062] Figure 2 It is schematically shown Figure 1 A magnified top view of the network is shown.

[0063] It should be noted that in Figure 2 In the figure, in order to show the configuration relationship between the network 70 and the base material pad 20, the base material pad 20 is also shown by a dotted line.

[0064] like Figure 2 As shown, the network 70 is formed by a plurality of bases 71 made of an organic substance and fibers 72 extending from the plurality of bases 71 in two directions.

[0065] Such a network 70 has high strength and flexibility, and thus can suppress the occurrence of cracks when the mat 10 is wound.

[0066] Here, as the fibers 72 , there are longitudinally oriented fibers 31 and transversely oriented fibers 32 extending in two directions, the longitudinal direction and the transverse direction, respectively.

[0067] The longitudinally oriented fibers 31 are oriented in the longitudinal direction and are aligned with the long side direction ( Figure 1 The direction indicated by the double arrow L is roughly parallel.

[0068] The orientation direction of the transversely oriented fibers 32 is transverse and is aligned with the short side direction ( Figure 1 The direction indicated by the double arrow W is roughly parallel.

[0069] Here, the direction in which the length direction of the fibers constituting the longitudinally oriented fibers 31 is arranged is the orientation direction of the longitudinally oriented fibers 31 , and the direction in which the length direction of the fibers constituting the transversely oriented fibers 32 is arranged is the orientation direction of the transversely oriented fibers 32 .

[0070] The longitudinally oriented fibers 31 in which the fibers are oriented (arranged) in the longitudinal direction and the transversely oriented fibers 32 in which the fibers are oriented (arranged) in the transverse direction are stacked to form a nonwoven fabric having fiber orientations in the longitudinal and transverse directions.

[0071] The nonwoven fabric composed of the fibers 72 is produced by a production process of direct spinning from a raw material, and the spun fibers are stretched in the longitudinal and transverse directions to orient the long fiber filaments in the longitudinal and transverse directions.

[0072] The nonwoven fabric formed of the fibers 72 has voids, and there are openings surrounded by the longitudinally oriented fibers 31 and the transversely oriented fibers 32 .

[0073] It should be noted that Figure 2 The figure shows the situation where the longitudinally oriented fibers 31 and the transversely oriented fibers 32 are stacked one layer each, but the number of layers of the longitudinally oriented fibers 31 and the transversely oriented fibers 32 is not particularly limited, and the longitudinally oriented fibers 31 and the transversely oriented fibers 32 can be alternately stacked in a total of more than 3 layers.

[0074] In addition, the order of laminating the longitudinally oriented fibers 31 and the transversely oriented fibers 32 is not particularly limited.

[0075] Furthermore, the network 70 may include fibers extending in three or more directions, and for example, may include fibers extending in an oblique direction in addition to the longitudinally oriented fibers 31 and the transversely oriented fibers 32 .

[0076] In addition, the relationship between the orientation direction of the longitudinally oriented fibers 31 and the transversely oriented fibers 32 and the long side direction and the short side direction of the mat 10 is not particularly limited. It is preferred that the orientation direction of one of the longitudinally oriented fibers 31 and the transversely oriented fibers 32 is parallel to the long side direction of the mat 10, and the orientation direction of the other of the longitudinally oriented fibers 31 and the transversely oriented fibers 32 is parallel to the short side direction of the mat 10.

[0077] The bases 71 are distributed in the network 70. Different from the fibers 72 extending one-dimensionally, each base 71 extends in the long side direction, short side direction and thickness direction (particularly the long side direction and short side direction) of the mat material 10. Furthermore, the fibers 72 extending in different directions are joined to each other by welding each base 71. That is, the base 71 is arranged in the region where the longitudinally oriented fibers 31 and the transversely oriented fibers 32 intersect, so that these fibers are joined to each other.

[0078] Thus, from the perspective of making the fibers 72 forming the network 70 more and more firmly bonded to each other, the maximum width of each base portion 71 is preferably greater than the width of the fiber 72. As a result, the generation of cracks when the mat material 10 is wound can be more effectively suppressed. For example, the base portion 71 may also be large enough to occupy at least a portion of the region where the plurality of longitudinally oriented fibers 31 and the plurality of transversely oriented fibers 32 intersect, but it is more preferred that one base portion 71 includes a plurality of regions where the longitudinally oriented fibers 31 and the transversely oriented fibers 32 intersect.

[0079] It should be noted that, here, the maximum width of each base portion 71 and the width of the fiber 72 are preferably compared when the network 70 is viewed from above.

[0080] The base portion 71 also plays a role in fixing the network 70 to the base mat 20. That is, the base portion 71 joins the fibers 72 forming the network 70 to the base mat 20 by welding.

[0081] As described above, the network 70 is formed by a non-woven fabric and a base 71, wherein the non-woven fabric is formed by layering fibers 72 oriented in multiple directions (for example, longitudinally oriented fibers 31 and transversely oriented fibers 32), and the base 71 is distributed on the non-woven fabric to connect fibers 72 of different orientation directions located in different layers to each other (for example, longitudinally oriented fibers 31 and transversely oriented fibers 32 to each other).

[0082] In this way, the network 70 is formed three-dimensionally. That is, the network 70 extends in the long-side direction and the short-side direction of the mat 10 and has a thickness in the thickness direction of the mat 10.

[0083] As a result, the strength of the web 70 is further improved, and the stress applied to the web 70 is dispersed, so that the occurrence of cracks when the mat 10 is wound can be more effectively suppressed.

[0084] It should be noted that Figure 2 , the network 70 includes a fiber bundle formed by interweaving a plurality of fibers and a single fiber, but the network 70 may be formed only of a fiber bundle or only of a single fiber.

[0085] The following describes the details of these configurations.

[0086] The base material mat constituting the mat material of the first embodiment of the present invention is composed of inorganic fibers. The inorganic fibers are not particularly limited and may be alumina-silica fibers, alumina fibers, silica fibers, etc. In addition, glass fibers or biosoluble fibers may also be used. As long as the properties required by the mat material such as heat resistance and wind erosion resistance are changed, it is preferred to use thick-diameter fibers and fibers of fiber length that are suitable for the environmental standards of various countries.

[0087] Among them, low-crystalline alumina inorganic fibers are preferred, and low-crystalline alumina inorganic fibers composed of mullite are more preferred. In addition, inorganic fibers composed of a spinel compound are further preferred.

[0088] The base material mat has a long side direction as a winding direction and a short side direction orthogonal to the long side direction.

[0089] In the base material mat, it is preferred that a convex portion is formed at one of the ends on the long side side of the base material mat, namely the first end, and a concave portion is formed at the other end, namely the second end. The convex portion and the concave portion of the base material mat are preferably shaped to fit into each other when the mat material is wound around an exhaust gas purification device, an exhaust gas treatment body, or an exhaust pipe having a cylindrical outer circumference.

[0090] Alternatively, the base material pad may have a shape without protrusions and recesses.

[0091] The thickness of the base material pad is preferably 2 mm to 30 mm.

[0092] If the thickness of the base material mat is less than 2 mm, the thickness is too thin, so the heat insulation performance and sound insulation performance are reduced. On the other hand, if the thickness of the base material mat exceeds 30 mm, the flexibility is reduced, and the assembly property to the component as the assembly object is reduced.

[0093] The bulk density of the substrate mat is not particularly limited, but is preferably 0.05 g / cm 3~0.30g / cm 3 .

[0094] If the bulk density of the substrate pad is less than 0.05 g / cm 3 On the other hand, if the bulk density of the substrate mat exceeds 0.30 g / cm 3 , the base material pad becomes hard, the assembly property to the component to be assembled is reduced, and the base material pad is easy to break.

[0095] On at least one of the first main surface and the second main surface of the base material forming the mat material of the first aspect of the present invention, a network is formed by a plurality of bases made of an organic substance and fibers extending from the plurality of bases in at least two directions.

[0096] The organic substance constituting the base is different from the material of the fibers forming the network (hereinafter referred to as network fibers). Specifically, the base is formed by thermally fusing hot-melt powder (hot-melt adhesive) to the network fibers.

[0097] Therefore, the glass transition temperature Tg1 of the network fiber is preferably higher than the glass transition temperature Tg2 of the organic substance constituting the base. Thus, a network having a base can be easily formed using hot-melt powder.

[0098] The glass transition temperature Tg1 of the network fiber is not particularly limited, but is preferably -140°C to 90°C, and more preferably -130°C to 80°C.

[0099] The glass transition temperature Tg2 of the organic substance constituting the base is not particularly limited, but is preferably -140°C to 90°C, and more preferably -130°C to 80°C.

[0100] Furthermore, the difference between the glass transition temperature Tg1 of the network fiber and the glass transition temperature Tg2 of the organic matter constituting the base, i.e. (Tg1-Tg2), is also not particularly limited, but is preferably 220°C or less, and more preferably 200°C or less in order to integrate the network fiber with the base.

[0101] The organic material constituting the base is not particularly limited as long as it can be used as a hot-melt powder, and specific examples thereof include polyethylene (PE), polyethylene terephthalate (PET), polyamide (PA), and ethylene-vinyl acetate copolymer resin (EVA).

[0102] The above-mentioned network fibers are preferably long fiber filaments.

[0103] The long fiber filaments are preferably longer than common short fiber lengths (eg, 10 mm to 50 mm), and the average fiber length of the filaments is preferably longer than 100 mm, and more preferably several hundred mm or more.

[0104] The long fiber filaments may be continuous long fibers.

[0105] The average fiber diameter of the network fiber is usually 10 μm or less, preferably about 5 μm, in the main constituent filaments.

[0106] The network preferably has substantially the same planar shape as the base material mat. That is, the arrangement area of ​​the network and the base material mat preferably substantially coincides when viewed from above.

[0107] In addition, it is preferred to form a sheet consisting of a network and attach the sheet to the base material mat. The attachment of the sheet to the base material mat is preferably performed by hot-melt powder.

[0108] The basis weight of the sheet composed of the network is not particularly limited, but is preferably 5 g / m 2 Above 100g / m 2 Below, more preferably 5g / m 2 Above 50g / m 2 Below, more preferably 5g / m 2 Above 30g / m 2 the following.

[0109] It should be noted that the basis weight of the sheet material referred to here is the basis weight per sheet material.

[0110] The network fibers are preferably composed of at least one of organic fibers and inorganic fibers.

[0111] For example, the longitudinally oriented fibers may be composed of organic fibers and / or inorganic fibers, and the transversely oriented fibers may be composed of organic fibers and / or inorganic fibers. The materials of the longitudinally oriented fibers and the transversely oriented fibers may be different from each other, but usually, when the longitudinally oriented fibers are composed of organic fibers, the transversely oriented fibers are also composed of organic fibers, and when the longitudinally oriented fibers are composed of inorganic fibers, the transversely oriented fibers are also composed of inorganic fibers.

[0112] The network fibers are more preferably composed of organic fibers, thereby more effectively suppressing the occurrence of cracks when the mat is wound.

[0113] For example, both the longitudinally oriented fibers and the transversely oriented fibers may be composed of organic fibers.

[0114] More specifically, suitable materials for the above-mentioned network fibers include polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP) and the like.

[0115] In the mat material according to the first aspect of the present invention, it is preferred that the base mat further include at least one of an inorganic binder and an organic binder.

[0116] The amount of the inorganic binder used (weight of the inorganic binder / weight of the mat material) may be, for example, more than 0 wt % and not more than 15 wt %.

[0117] The amount of the organic binder (weight of the organic binder / weight of the mat material) may be more than 0 wt % and less than 15 wt %.

[0118] As the inorganic binder, alumina sol, silica sol, or the like can be used.

[0119] As the organic binder, acrylic resin, acrylate emulsion, rubber emulsion, water-soluble organic polymer such as carboxymethyl cellulose and polyvinyl alcohol, thermoplastic resin such as styrene resin, thermosetting resin such as epoxy resin, etc. are preferably used.

[0120] Next, a method for producing the mat material of the first aspect of the present invention, that is, a method for producing the mat material of the present invention will be described.

[0121] The manufacturing method of the mat material of the present invention is characterized in that it comprises: a base mat preparation step, preparing a base mat containing inorganic fibers and having a first main surface and a second main surface; a sheet material preparation step, preparing a sheet material containing fibers extending in at least two directions; a sheet material processing step, spreading hot-melt powder on the above-mentioned sheet material and heating it to make the above-mentioned hot-melt powder adhere to the above-mentioned sheet material; and a sheet material attaching step, hot-pressing the above-mentioned sheet material to which the above-mentioned hot-melt powder is attached to at least one of the above-mentioned first main surface and the second main surface of the above-mentioned base mat, and attaching the above-mentioned sheet material to the above-mentioned base mat.

[0122] In the method for producing a mat of the present invention, it is preferred to produce two types of mats. The two types of mats are a first mat and a second mat, and both of the mats are the mat of the first embodiment of the present invention.

[0123] In the method for producing a mat of the present invention, first, a base mat having a first main surface and a second main surface and a sheet including fibers extending in at least two directions are prepared.

[0124] The structure and physical properties of the base material mat prepared here are the same as those of the base material mat described in the mat material of the first embodiment of the present invention, and therefore detailed descriptions thereof are omitted here.

[0125] In addition, the structure and physical properties of the sheet prepared here are the same as the network described in the mat material of the first embodiment of the present invention, except that it does not have a base portion, and therefore detailed description is omitted here.

[0126] However, the base mat and sheet material prepared here are preferably large-sized sheets from which a plurality of mat materials of the first embodiment of the present invention can be obtained by punching.

[0127] The base mat can be obtained by various methods, for example, by papermaking or needle punching.

[0128] In the case of the papermaking method, it can be produced by, for example, the following method.

[0129] The inorganic fibers are opened and dispersed in a solvent to prepare a mixed solution. The mixed solution is flowed into a former having a filter net formed on the bottom surface, and the solvent in the mixed solution is desolventized to obtain an inorganic fiber aggregate. Thereafter, the inorganic fiber aggregate is dried to obtain a substrate mat.

[0130] In the case of the needle punching method, it can be produced, for example, by the following method.

[0131] A spinning mixture made of alkaline aluminum chloride aqueous solution and silica sol as raw materials is spun by a blow spinning method to produce an inorganic fiber precursor having an average fiber diameter of 3 μm to 10 μm. Next, the inorganic fiber precursor is compressed to produce a continuous base mat of a specified size, and a sintering treatment is performed to obtain a base mat. Needle punching treatment is performed at any stage before or after the sintering treatment to interweave the inorganic fibers.

[0132] The sheet can be produced, for example, by the following method.

[0133] First, a raw material (such as a resin) is melt-spun by a nonwoven spinning device such as a meltblown nonwoven fabric or a spunbond nonwoven fabric. Next, the fibers are arranged in the longitudinal direction (MD) and the transverse direction (CD) and stretched to produce a longitudinally stretched web formed by longitudinally stretching a continuum composed of long fiber filaments, and a transversely stretched web formed by transversely stretching a continuum composed of the same long fiber filaments. After that, the longitudinally stretched web and the transversely stretched web are laminated and joined to produce a laminated sheet (nonwoven fabric) formed by laminating longitudinally oriented fibers and transversely oriented fibers.

[0134] As a method for joining the longitudinally stretched web and the transversely stretched web, for example, a water jet method, a needle punch method, a hot air method, a heat embossing method, an adhesive bonding method, a stitch bonding method, an ultrasonic sealing method, an induction heating sealing method, etc. can be used.

[0135] Next, hot-melt powder (powdered hot-melt adhesive) is spread on the sheet and heated to allow the hot-melt powder to adhere to the sheet.

[0136] It should be noted that the heating temperature and heating time at this time are not particularly limited and can be appropriately set according to the characteristics of the hot-melt powder.

[0137] Next, the sheet material to which the hot-melt powder is attached is thermally compressed and bonded to at least one of the first main surface and the second main surface of the base material mat, thereby attaching the sheet material to the base material mat.

[0138] In this case, it is preferable to obtain an adhered body by adhering a large-sized sheet to a large-sized base material pad.

[0139] It should be noted that the conditions for hot pressing at this time are not particularly limited and can be appropriately set according to the characteristics of the hot melt powder. The heating temperature is preferably between 115°C and 140°C, more preferably between 120°C and 130°C, and the heating time is preferably between 25 seconds and 60 seconds, more preferably between 30 seconds and 50 seconds.

[0140] Figure 3 It is a perspective view schematically showing an example of an attached body.

[0141] The attached body 150 is formed by attaching the large-sized sheet 130 to the first main surface 121 of the large-sized base mat 120 , and is a rectangular sheet having two longitudinal sides and two transverse sides.

[0142] The sheet 130 is a sheet formed by stacking longitudinally oriented fibers and transversely oriented fibers. The longitudinally oriented fibers of the sheet 130 are oriented longitudinally and parallel to the two longitudinal sides of the attached body 150 . The transversely oriented fibers of the sheet 130 are oriented transversely and parallel to the two transverse sides of the attached body 150 .

[0143] Next, by punching the attached body, a mat material of a predetermined shape can be produced.

[0144] In the manufacturing method of the mat material of the present invention, hot-melt powder is spread on a sheet material containing fibers extending in at least two directions and heated, so that the hot-melt powder is attached to the sheet material, the sheet material attached with the hot-melt powder is hot-pressed to at least one of the first main surface and the second main surface of the substrate pad, and the sheet material is attached to the above-mentioned substrate pad, so that the sheet material can be attached to the substrate pad while preventing the fibers formed by the sheet material, that is, the network fibers themselves from melting. Therefore, the strength and flexibility of the network fibers can be suppressed from being reduced. In addition, by heating and melting the hot-melt powder, a network with a base can be formed. As a result, cracks can be suppressed from occurring when the mat material is wound.

[0145] In the punching process of the attached body, it is preferred to perform a process of obtaining a first mat material in which the longitudinal direction of the attached body is the long side direction of the mat material and the transverse direction of the attached body is the short side direction of the mat material, and a second mat material in which the transverse direction of the attached body is the long side direction of the mat material and the longitudinal direction of the attached body is the short side direction of the mat material, thereby obtaining two types of mat materials, the first mat material and the second mat material.

[0146] Figure 4It is a plan view schematically showing an example of a process of obtaining two types of mat materials by punching.

[0147] for Figure 4 The attached body 150 shown is punched out to obtain two types of mat materials.

[0148] Figure 4 The left side shows the orientation direction of the longitudinally oriented fibers of the obtained sheet ( Figure 4 The longitudinal direction shown in the figure is the long side direction of the mat material, and the transverse orientation direction of the sheet material is the orientation direction of the fibers ( Figure 4 The first mat material 1 has a transverse direction (as shown) that is a short side direction of the mat material.

[0149] in addition, Figure 4 The right side of the figure shows the orientation direction of the transversely oriented fibers of the obtained sheet ( Figure 4 The transverse direction shown in the figure is the long side direction of the mat material, and the longitudinal orientation direction of the sheet material ( Figure 4 The second mat material 2 has the longitudinal direction (as shown) as the short side direction of the mat material.

[0150] In the first mat 1 and the second mat 2, the number and density of fibers of the sheet oriented along the long side direction of the mat (longitudinally oriented fibers or transversely oriented fibers) and the fibers of the sheet oriented along the short side direction of the mat (transversely oriented fibers or longitudinally oriented fibers) are the same, and therefore they show approximately the same tensile strength and windability.

[0151] In the punching process, it is preferred that the orientation direction of one of the longitudinally oriented fibers and the transversely oriented fibers of the sheet be parallel to the long side direction of the first mat and parallel to the short side direction of the second mat.

[0152] In addition, it is preferred that the orientation direction of the other of the longitudinally oriented fibers and the transversely oriented fibers of the sheet be parallel to the short-side direction of the first mat and parallel to the long-side direction of the second mat.

[0153] Figure 4 The punching direction shown is the direction that satisfies the above conditions.

[0154] In the method for producing the mat of the present invention, a method using a sheet including fibers extending in at least two directions has been described. However, the mat of the first aspect of the present invention may be produced without using such a sheet.

[0155] For example, hot-melt powder may be used to sequentially laminate fibers extending in different directions on at least one of the first and second main surfaces of the base mat. More specifically, the longitudinally oriented fibers (longitudinally extended web) may be firstly hot-pressed to at least one of the first and second main surfaces of the base mat using hot-melt powder, and then the transversely oriented fibers (transversely extended web) may be hot-pressed to the longitudinally oriented fibers using hot-melt powder.

[0156] Next, a mat material according to a second aspect of the present invention will be described.

[0157] The second aspect of the mat material of the present invention is characterized in that on at least one of the first and second main surfaces of a base mat including inorganic fibers and having a first and second main surfaces, a fiber bundle and single fibers formed by interweaving a plurality of fibers form a network.

[0158] Figure 5 It is a perspective view schematically showing an example of a mat material according to a second aspect of the present invention.

[0159] Figure 5 The mat material 210 shown in the figure has the following structure: on the first main surface 221 of the base material mat 220 having the first main surface 221 and the second main surface 222, a fiber bundle and a single fiber (both on the first main surface 221 and the second main surface 222) are formed. Figure 5 A mesh 270 (not shown in the figure) is formed.

[0160] On the long side of the mat 210 ( Figure 5 A convex portion 211 is formed at one of the ends (in the direction indicated by the double arrow L), that is, the first end, and a concave portion 212 is formed at the other end, that is, the second end.

[0161] The convex portion 211 and the concave portion 212 are formed by overlapping convex portions and concave portions provided on the base material pad 220 and the mesh 270 , respectively.

[0162] The convex and concave portions of the mat material are shaped so as to fit into each other when the mat material is wound around an exhaust gas purifying device, an exhaust gas treating body, or an exhaust pipe having a cylindrical outer circumference.

[0163] It should be noted that in Figure 5 , the direction indicated by the double arrow W is the short side direction of the mat material, and the direction indicated by the double arrow T is the thickness direction of the mat material.

[0164] It should be noted that Figure 5 2 shows a case where the mesh 270 is formed only on the first main surface 221 of the substrate pad 220, but the mesh 270 may be formed on each of the first main surface 221 and the second main surface 222 of the substrate pad 220. In addition, the mesh 270 may be formed on the side surface of the substrate pad 220 in addition to the first main surface 221 and / or the second main surface 222 of the substrate pad 220.

[0165] Figure 6 It is schematically shown Figure 5 An enlarged top view of the mesh is shown.

[0166] It should be noted that in Figure 6In order to show the configuration relationship between the mesh 270 and the base material pad 220, the base material pad 220 is also shown by a dotted line.

[0167] like Figure 6 As shown, the web 270 is formed of a fiber bundle 271 formed by interweaving a plurality of fibers and a single fiber 272 .

[0168] Therefore, it is possible to suppress a decrease in the strength and flexibility of the fibers forming the mesh 270 , and thus it is possible to suppress the occurrence of cracks when the mat 210 is wound.

[0169] The plurality of fibers constituting the fiber bundle 271 are twisted and entangled with each other. In this way, the fibers constituting the fiber bundle 271 are not fused with each other but are only entangled with each other, so that the softness of the web 270 can be suppressed from being reduced as described above.

[0170] The number of fibers constituting the fiber bundle 271 is not particularly limited, but is preferably 2 to 10, and more preferably 3 to 7.

[0171] It should be noted that the single fiber 272 is a fiber that is not entangled with other fibers.

[0172] The fiber bundles 271 include a plurality of fiber bundles extending in different directions from each other, and the web 270 is formed by these plurality of fiber bundles and the single fibers 272. As a result, in the web 270, the number of fibers in the longitudinal direction and the number of fibers in the transverse direction can be made equal.

[0173] Here, as fibers forming the web 270, there are longitudinally oriented fibers 231 and transversely oriented fibers 232 extending in two directions, namely, the longitudinal direction and the transverse direction.

[0174] The longitudinally oriented fibers 231 are oriented in the longitudinal direction and are aligned with the long side direction ( Figure 6 The direction indicated by the double arrow L is roughly parallel.

[0175] The orientation direction of the transversely oriented fibers 232 is transverse and is aligned with the short side direction ( Figure 6 The direction indicated by the double arrow W is roughly parallel.

[0176] Here, the direction in which the length direction of the fibers constituting the longitudinally oriented fibers 231 is arranged becomes the orientation direction of the longitudinally oriented fibers 231 , and the direction in which the length direction of the fibers constituting the transversely oriented fibers 232 is arranged becomes the orientation direction of the transversely oriented fibers 232 .

[0177] The longitudinally oriented fibers 231 in which the fibers are oriented (arranged) in the longitudinal direction and the transversely oriented fibers 232 in which the fibers are oriented (arranged) in the transverse direction are stacked to form a nonwoven fabric having fiber orientations in the longitudinal and transverse directions.

[0178] This nonwoven fabric is produced by a production process of direct spinning from a raw material, and the spun fibers are stretched in the longitudinal and transverse directions to orient long fiber filaments in the longitudinal and transverse directions.

[0179] In addition, the nonwoven fabric has voids, and there are openings surrounded by the longitudinally oriented fibers 231 and the transversely oriented fibers 232 .

[0180] Furthermore, some of the longitudinally oriented fibers 231 are intertwined to form longitudinally oriented fiber bundles 271a extending in the longitudinal direction, and the remaining fibers of the longitudinally oriented fibers 231 exist as longitudinally oriented single fibers 272a extending in the longitudinal direction.

[0181] Similarly, part of the transversely oriented fibers 232 are interwoven to form transversely oriented fiber bundles 271b extending in the transverse direction, and the remaining fibers of the transversely oriented fibers 232 exist as transversely oriented single fibers 272b extending in the transverse direction.

[0182] However, the fibers forming the mesh 270 do not necessarily need to extend in a straight line, and it is preferred that at least a portion of the fibers forming the mesh 270 be bent. Figure 6 As shown, it is preferred that there are curved fiber bundles 271c and curved single fibers 272c. Thus, the intersections of the fibers forming the mesh 270 are increased, and the stress applied to the mesh 270 can be dispersed, thereby further suppressing the generation of cracks when the mat 210 is wound.

[0183] More specifically, the bent fiber bundle 271c and the bent single fiber 272c are each bent in, for example, an arc shape along the orientation direction (longitudinal direction or transverse direction) thereof.

[0184] It should be noted that only one of the bent fiber bundle 271 c and the bent single fiber 272 c may be present, but from the viewpoint of suppressing cracks in the mat 210 , it is preferable that both of them be present.

[0185] in addition, Figure 6 The figure shows the situation where the longitudinally oriented fibers 231 and the transversely oriented fibers 232 are stacked in one layer respectively, but the number of layers of the longitudinally oriented fibers 231 and the transversely oriented fibers 232 is not particularly limited, and the longitudinally oriented fibers 231 and the transversely oriented fibers 232 can be alternately stacked in a total of more than 3 layers.

[0186] In addition, the order of laminating the longitudinally oriented fibers 231 and the transversely oriented fibers 232 is not particularly limited.

[0187] In this way, the mesh 270 is formed three-dimensionally. That is, the mesh 270 extends in the long-side direction and the short-side direction of the mat material 210 and has a thickness in the thickness direction of the mat material 210.

[0188] As a result, the strength of the mesh 270 is further improved, and the stress applied to the mesh 270 is dispersed, so that the occurrence of cracks when the mat 210 is wound can be more effectively suppressed.

[0189] It should be noted that the mesh 270 may include fibers extending in more than three directions. For example, in addition to the longitudinally oriented fibers 231 and the transversely oriented fibers 232, it may also include fibers extending in an oblique direction. There may also be fiber bundles and single fibers extending in the oblique direction using these fibers.

[0190] In addition, the relationship between the orientation direction of the longitudinally oriented fibers 231 and the transversely oriented fibers 232 and the long side direction and short side direction of the mat material 210 is not particularly limited. It is preferred that the orientation direction of one of the longitudinally oriented fibers 231 and the transversely oriented fibers 232 is parallel to the long side direction of the mat material 210, and the orientation direction of the other of the longitudinally oriented fibers 231 and the transversely oriented fibers 232 is parallel to the short side direction of the mat material 210.

[0191] That is, it is preferred that the orientation direction of either the longitudinally oriented fiber bundle 271a and the longitudinally oriented single fiber 272a, or the transversely oriented fiber bundle 271b and the transversely oriented single fiber 272b extending in the transverse direction is parallel to the long side direction of the mat material 210, and the orientation direction of the other is parallel to the short side direction of the mat material 210.

[0192] Figure 5 and Figure 6 The mesh 270 shown further includes a plurality of bases 273 made of an organic substance, and fiber bundles 271 and single fibers 272 extend from the bases 273 in a plurality of directions.

[0193] The bases 273 are distributed in the mesh 270, and each base 273, unlike the fibers extending one-dimensionally, extends in the long side direction, short side direction, and thickness direction (particularly the long side direction and short side direction) of the mat material 210. Furthermore, the fiber bundles 271 and single fibers 272 extending in different directions are joined to each other by welding each base 273. That is, the base 273 is arranged in the region where the fiber bundles 271 and single fibers 272 intersect, and these fibers are joined to each other.

[0194] In addition, the base portion 273 plays a role of fixing the mesh 270 to the base mat 220. That is, the base portion 273 joins the fibers forming the mesh 270 to the base mat 220 by welding.

[0195] In this way, the mesh 270 is formed by a non-woven fabric formed by layering fiber bundles 271 and single fibers 272 oriented in multiple directions (for example, longitudinally oriented fibers 231 and transversely oriented fibers 232), and a base 273 distributed on the non-woven fabric and connecting fibers of different orientation directions located in different layers to each other (for example, longitudinally oriented fibers 231 and transversely oriented fibers 232 to each other).

[0196] The following describes the details of these configurations.

[0197] The base material mat constituting the mat material of the second embodiment of the present invention is composed of inorganic fibers. The inorganic fibers are not particularly limited and may be alumina-silica fibers, alumina fibers, silica fibers, etc. In addition, glass fibers or biosoluble fibers may also be used. As long as the properties required by the mat material such as heat resistance and wind erosion resistance are changed, it is preferred to use thick-diameter fibers and fibers of fiber length that are suitable for the environmental standards of various countries.

[0198] Among them, low-crystalline alumina inorganic fibers are preferred, and low-crystalline alumina inorganic fibers composed of mullite are more preferred. In addition, inorganic fibers composed of a spinel compound are further preferred.

[0199] The base material mat has a long side direction as a winding direction and a short side direction orthogonal to the long side direction.

[0200] In the base material mat, it is preferred that a convex portion is formed at one of the ends on the long side side of the base material mat, namely the first end, and a concave portion is formed at the other end, namely the second end. The convex portion and the concave portion of the base material mat are preferably shaped to fit into each other when the mat material is wound around an exhaust gas purification device, an exhaust gas treatment body, or an exhaust pipe having a cylindrical outer circumference.

[0201] Alternatively, the base material pad may have a shape without protrusions and recesses.

[0202] The thickness of the base material pad is preferably 2 mm to 30 mm.

[0203] If the thickness of the base material mat is less than 2 mm, the thickness is too thin, so the heat insulation performance and sound insulation performance are reduced. On the other hand, if the thickness of the base material mat exceeds 30 mm, the flexibility is reduced, and the assembly property to the component as the assembly object is reduced.

[0204] The bulk density of the substrate mat is not particularly limited, but is preferably 0.05 g / cm 3 ~0.30g / cm 3 .

[0205] If the bulk density of the substrate pad is less than 0.05 g / cm 3On the other hand, if the bulk density of the substrate mat exceeds 0.30 g / cm 3 , the base material pad becomes hard, the assembly property to the component to be assembled is reduced, and the base material pad is easy to break.

[0206] On at least one of the first main surface and the second main surface of the base mat constituting the mat material of the second aspect of the present invention, a network is formed by fiber bundles and single fibers formed by intertwining a plurality of fibers.

[0207] The fibers forming the web (hereinafter referred to as web fibers) are preferably long-fiber filaments.

[0208] The long fiber filaments are preferably longer than common short fiber lengths (eg, 10 mm to 50 mm), and the average fiber length of the filaments is preferably longer than 100 mm, and more preferably several hundred mm or more.

[0209] The long fiber filaments may be continuous long fibers.

[0210] The average fiber diameter of the web fibers is usually 10 μm or less, preferably about 5 μm, in the main constituent filaments.

[0211] The mesh may further include a plurality of bases made of organic matter.

[0212] The organic substance constituting the base is made of a different material from the mesh fibers. Specifically, the base is formed by thermally fusing hot-melt powder (hot-melt adhesive) to the mesh fibers.

[0213] Therefore, the glass transition temperature Tg3 of the mesh fibers is preferably higher than the glass transition temperature Tg4 of the organic matter constituting the base. Thus, a mesh having a base can be easily formed using hot-melt powder.

[0214] The glass transition temperature Tg3 of the web fibers is not particularly limited, but is preferably -140°C to 90°C, and more preferably -130°C to 80°C.

[0215] The glass transition temperature Tg4 of the organic substance constituting the base is not particularly limited either, but is preferably -140°C to 90°C, and more preferably -130°C to 80°C.

[0216] Furthermore, the difference between the glass transition temperature Tg3 of the mesh fiber and the glass transition temperature Tg4 of the organic matter constituting the base, i.e. (Tg3-Tg4), is also not particularly limited, but is preferably 220°C or less, and more preferably 200°C or less in order to integrate the mesh fiber with the base.

[0217] The organic material constituting the base is not particularly limited as long as it can be used as a hot-melt powder, and specific examples thereof include polyethylene (PE), polyethylene terephthalate (PET), polyamide (PA), and ethylene-vinyl acetate copolymer resin (EVA).

[0218] The mesh preferably has substantially the same planar shape as the base material mat, that is, preferably, the arrangement areas of the mesh and the base material mat are substantially consistent when viewed from above.

[0219] In addition, it is preferred to form a sheet made of a mesh and attach the sheet to the base material pad. The attachment of the sheet to the base material pad is preferably performed using hot-melt powder.

[0220] The basis weight of the sheet composed of the mesh is not particularly limited, but is preferably 5 g / m 2 Above 100g / m 2 Below, more preferably 5g / m 2 Above 50g / m 2 Below, more preferably 5g / m 2 Above 30g / m 2 the following.

[0221] It should be noted that the basis weight of the sheet material referred to here is the basis weight per sheet material.

[0222] The mesh fibers are preferably composed of at least one of organic fibers and inorganic fibers.

[0223] For example, the longitudinally oriented fibers may be composed of organic fibers and / or inorganic fibers, and the transversely oriented fibers may be composed of organic fibers and / or inorganic fibers. The materials of the longitudinally oriented fibers and the transversely oriented fibers may be different from each other, but usually, when the longitudinally oriented fibers are composed of organic fibers, the transversely oriented fibers are also composed of organic fibers, and when the longitudinally oriented fibers are composed of inorganic fibers, the transversely oriented fibers are also composed of inorganic fibers.

[0224] The web fibers are more preferably composed of organic fibers, thereby more effectively suppressing the occurrence of cracks when the mat is wound.

[0225] For example, both the longitudinally oriented fibers and the transversely oriented fibers may be composed of organic fibers.

[0226] More specifically, suitable materials for the web fibers include polyethylene terephthalate (PET), polyethylene (PE), and polypropylene (PP).

[0227] In the mat material according to the second aspect of the present invention, it is preferred that the base mat further include at least one of an inorganic binder and an organic binder.

[0228] The amount of the inorganic binder used (weight of the inorganic binder / weight of the mat material) may be, for example, more than 0 wt % and not more than 15 wt %.

[0229] The amount of the organic binder (weight of the organic binder / weight of the mat material) may be more than 0 wt % and less than 15 wt %.

[0230] As the inorganic binder, alumina sol, silica sol, or the like can be used.

[0231] As the organic binder, acrylic resin, acrylate emulsion, rubber emulsion, water-soluble organic polymer such as carboxymethyl cellulose and polyvinyl alcohol, thermoplastic resin such as styrene resin, thermosetting resin such as epoxy resin, etc. are preferably used.

[0232] Next, a method for producing a mat according to a second aspect of the present invention will be described.

[0233] The manufacturing method of the second embodiment of the mat material of the present invention can be manufactured through the following steps: a base material mat preparation step, preparing a base material mat containing inorganic fibers and having a first main surface and a second main surface; a sheet material preparation step, preparing a sheet material containing a fiber bundle and a single fiber formed by interweaving a plurality of fibers; a sheet material processing step, spreading hot-melt powder on the above-mentioned sheet material and heating it to make the above-mentioned hot-melt powder adhere to the above-mentioned sheet material; and a sheet material attaching step, hot-pressing the above-mentioned sheet material to which the above-mentioned hot-melt powder is attached to at least one of the above-mentioned first main surface and the second main surface of the above-mentioned base material mat, and attaching the above-mentioned sheet material to the above-mentioned base material mat.

[0234] In this case, it is preferable to manufacture two kinds of mats. The two kinds of mats are a first mat and a second mat, and both of the mats are the mats of the second embodiment of the present invention.

[0235] In the above production method, first, a base mat having a first main surface and a second main surface and a sheet including fiber bundles and single fibers formed by intertwining a plurality of fibers are prepared.

[0236] The structure and physical properties of the base material mat prepared here are the same as those of the base material mat described in the mat material of the second embodiment of the present invention, and therefore detailed descriptions thereof are omitted here.

[0237] The structure and physical properties of the sheet material prepared here are the same as those of the mesh material described in the mat material of the second embodiment of the present invention, except that it does not have a base portion, and therefore detailed descriptions thereof are omitted here.

[0238] However, the base mat and sheet material prepared here are preferably large-sized sheets from which a plurality of mat materials of the second embodiment of the present invention can be obtained by punching.

[0239] The base mat can be obtained by various methods, for example, by papermaking or needle punching. More specifically, it can be produced by the method described in the method for producing the mat of the first embodiment of the present invention, that is, the method for producing the mat of the present invention.

[0240] The sheet can be produced, for example, by the method that can produce the mat of the first aspect of the present invention, that is, by the method described in the method for producing the mat of the present invention.

[0241] Figure 7 It is a perspective view schematically showing another example of an attached body.

[0242] The attached body 350 is formed by attaching the large-sized sheet 330 to the first main surface 321 of the large-sized base material pad 320 , and is a rectangular sheet having two longitudinal sides and two transverse sides.

[0243] The sheet 330 is a sheet formed by stacking longitudinally oriented fibers and transversely oriented fibers (both including fiber bundles and single fibers). The longitudinally oriented fibers of the sheet 330 are oriented longitudinally and are parallel to the two longitudinal sides of the attached body 350. The transversely oriented fibers of the sheet 330 are oriented transversely and are parallel to the two transverse sides of the attached body 350.

[0244] Next, by punching the attached body, a mat material of a predetermined shape can be produced.

[0245] In the above-mentioned manufacturing method, hot-melt powder is spread on a sheet material including a fiber bundle and a single fiber formed by interweaving a plurality of fibers and heated, so that the hot-melt powder is attached to the sheet material, and the sheet material attached with the hot-melt powder is hot-pressed to at least one of the first main surface and the second main surface of the substrate pad, and the sheet material is attached to the above-mentioned substrate pad, so that the sheet material can be attached to the substrate pad while preventing the fibers forming the sheet material, that is, the mesh fibers themselves from melting. Therefore, the strength and flexibility of the mesh fibers can be more effectively suppressed from being reduced. As a result, the generation of cracks when the mat material is wound can be more effectively suppressed.

[0246] In the punching process of the attached body, it is preferred to perform a process of obtaining a first mat material in which the longitudinal direction of the attached body is the long side direction of the mat material and the transverse direction of the attached body is the short side direction of the mat material, and a second mat material in which the transverse direction of the attached body is the long side direction of the mat material and the longitudinal direction of the attached body is the short side direction of the mat material, thereby obtaining two types of mat materials, the first mat material and the second mat material.

[0247] Figure 8 This is a plan view schematically showing another example of the process of obtaining two types of mat materials by punching.

[0248] for Figure 8 The attached body 350 shown is punched out to obtain two types of mat materials.

[0249] Figure 8 The left side shows the orientation direction of the longitudinally oriented fibers (including fiber bundles and single fibers) of the obtained sheet ( Figure 8 The longitudinal direction shown in the figure is the long side direction of the mat material, and the transversely oriented fibers (including fiber bundles and single fibers) of the sheet are oriented in the direction ( Figure 8 The lateral direction (as shown) is the first mat material 201 in the short side direction of the mat material.

[0250] in addition, Figure 8 The right side of the figure shows the orientation direction of the transversely oriented fibers (including fiber bundles and single fibers) of the obtained sheet ( Figure 8 The transverse direction shown in the figure is the long side direction of the mat material, and the longitudinal orientation direction of the sheet material (including fiber bundles and single fibers) is the orientation direction ( Figure 8 The second mat material 202 has its longitudinal direction (as shown) as the short side direction of the mat material.

[0251] In the first mat 201 and the second mat 202, the number and density of fibers of the sheet oriented along the long side direction of the mat (longitudinally oriented fibers or transversely oriented fibers) and the fibers of the sheet oriented along the short side direction of the mat (transversely oriented fibers or longitudinally oriented fibers) are the same, and therefore they show approximately the same tensile strength and windability.

[0252] In the punching process, it is preferred that the orientation direction of one of the longitudinally oriented fibers and the transversely oriented fibers of the sheet be parallel to the long side direction of the first mat and parallel to the short side direction of the second mat.

[0253] In addition, it is preferred that the orientation direction of the other of the longitudinally oriented fibers and the transversely oriented fibers of the sheet be parallel to the short-side direction of the first mat and parallel to the long-side direction of the second mat.

[0254] Figure 8 The punching direction shown is the direction that satisfies the above conditions.

[0255] It should be noted that in the above-mentioned manufacturing method, a method of using a sheet material (a layered sheet material formed by layering longitudinally oriented fibers and transversely oriented fibers) comprising a fiber bundle and a single fiber formed by interweaving a plurality of fibers and a hot-melt powder is described, but the second mode of the mat material of the present invention can also be manufactured without using these materials.

[0256] Specifically, for example, longitudinally oriented fibers (longitudinally stretched web) comprising fiber bundles and single fibers impregnated with a binder can be hot-compressed on at least one of the first main surface and the second main surface of the base material pad, and then transversely oriented fibers (transversely stretched web) comprising fiber bundles and single fibers impregnated with a binder can be hot-compressed on the longitudinally oriented fibers.

[0257] Hereinafter, the exhaust gas purification device of the present invention will be described.

[0258] The exhaust gas purification device of the present invention comprises: an exhaust gas treatment body, which is used for exhaust gas circulation; a retaining sealing material, which is wound around the outer periphery of the above-mentioned exhaust gas treatment body; and an outer shell, which accommodates the above-mentioned exhaust gas treatment body wound with the above-mentioned retaining sealing material. The exhaust gas purification device is characterized in that the above-mentioned retaining sealing material is a mat material of the first or second mode of the present invention.

[0259] As described above, the mats of the first and second aspects of the present invention can suppress the generation of cracks during winding. Therefore, the exhaust gas purifying device of the present invention can suppress the leakage of untreated exhaust gas from cracks in the mat (holding sealing material).

[0260] Fig. 9 This is a cross-sectional view schematically showing an example of the exhaust gas purification device of the present invention.

[0261] like Fig. 9 As shown, the exhaust gas purification device 100 of the present invention includes: a housing 50; an exhaust gas treatment body 40, which is accommodated in the housing 50 and allows exhaust gas to flow; and a holding sealing material 60, which is arranged between the exhaust gas treatment body 40 and the housing 50 to hold the exhaust gas treatment body 40.

[0262] The holding sealing material 60 is a mat material wound around the outer circumference of the exhaust gas treating body.

[0263] The exhaust gas treatment body 40 is a columnar exhaust gas treatment body in which a plurality of cells 41 are arranged in parallel in the longitudinal direction via cell walls 42. One end of the cell is sealed by a sealing material 43.

[0264] Note that, an introduction pipe for introducing exhaust gas exhausted from the internal combustion engine and an exhaust pipe for exhausting the exhaust gas that has passed through the exhaust gas purification device to the outside are connected to the end of the housing 50 as necessary.

[0265] Below, refer to Fig. 9 A case where exhaust gas passes through the exhaust gas purification device 100 having the above-mentioned structure will be described.

[0266] like Fig. 9 As shown, the exhaust gas ( Fig. 9 In the figure, G represents exhaust gas and arrows represent the flow of exhaust gas) flows into a channel 41 opened on the exhaust gas inlet side end face of the exhaust gas treatment body (honeycomb filter) 40, and passes through the channel wall 42 separating the channel 41. At this time, PM in the exhaust gas is captured by the channel wall 42, and the exhaust gas is purified. The purified exhaust gas flows out from other channels 41 opened on the exhaust gas outflow side end face and is discharged to the outside.

[0267] exist Fig. 9In the exhaust gas purification device 100 shown, the sealing material 60 is a mat material of the first or second embodiment of the present invention, and at least one of the first main surface and the second main surface of the sealing material 60 is composed of a network constituting the mat material of the first embodiment of the present invention, or a mesh constituting the mat material of the second embodiment of the present invention.

[0268] The material constituting the outer shell of the exhaust gas purification device of the present invention is not particularly limited as long as it is a heat-resistant metal, and specific examples thereof include metals such as stainless steel, aluminum, and iron.

[0269] In addition, the shape of the outer shell may be a clamshell shape, a shape having a substantially elliptical cross section, a substantially polygonal shape, or the like, other than a substantially cylindrical shape.

[0270] It should be noted that Fig. 9 The exhaust gas treatment body 40 shown is a filter in which any end of the pores 41 is sealed by a sealing material 43, but the ends of the pores in the exhaust gas treatment body constituting the exhaust gas purification device of the present invention may not be sealed. Such an exhaust gas treatment body can be suitably used as a catalyst carrier.

[0271] The exhaust gas treating body 40 may be made of non-oxide porous ceramics such as silicon carbide and silicon nitride, or may be made of oxide porous ceramics such as alumina, cordierite, and mullite. Among these, silicon carbide is preferred.

[0272] The cell density in the cross section of the exhaust gas treatment body 40 is not particularly limited, but the preferred lower limit is 31.0 cells / cm 2 (200pcs / inch 2 ), the preferred upper limit is 93.0 pcs / cm 2 (600pcs / inch 2 ). In addition, the more preferred lower limit is 38.8 pieces / cm 2 (250pcs / inch 2 ), and the more preferred upper limit is 77.5 pieces / cm 2 (500pcs / inch 2 ).

[0273] The exhaust gas treatment body 40 may carry a catalyst for purifying the exhaust gas. As the catalyst carried, for example, precious metals such as platinum, palladium, and rhodium are preferred, and platinum is more preferred. In addition, as other catalysts, alkali metals such as potassium and sodium, and alkaline earth metals such as barium may also be used. These catalysts may be used alone or in combination of two or more.

[0274] If these catalysts are supported, PM can be easily burned and removed, and toxic exhaust gas can also be purified.

[0275] It should be noted that the use of the mat material of the present invention is not particularly limited. In addition to the use in the exhaust gas purification device, it can also be used for batteries. In more detail, it can also be used for power storage devices used in electric vehicles or hybrid vehicles driven by electric motors. For example, by configuring the surface of power storage device components such as battery cells and bus bars connecting battery cells in the power storage device, even in the case of thermal runaway such as a battery cell rapidly heating up and continuing to generate heat due to internal short circuit, overcharging, etc. of the battery cell, damage to other power storage device components can be suppressed.

[0276] In addition, by using the mat material of the present invention in the top cover, side wall and bottom wall of the battery case that contains the battery, even if a flame is generated during thermal runaway, it can be reliably prevented from spreading to the outside. In this case, it is more preferable to use the mat material of the present invention in layers.

[0277] The following matters are disclosed in this specification.

[0278] The present disclosure (1) is a mat material, characterized in that, on at least one of the first main surface and the second main surface of a base material mat comprising inorganic fibers and having a first main surface and a second main surface, a network is formed by a plurality of bases composed of organic matter and fibers extending from the plurality of bases in at least two directions, respectively.

[0279] The present disclosure (2) is the mat material described in the present disclosure (1), wherein the maximum width of each of the plurality of bases is greater than the width of the fibers forming the network.

[0280] The present disclosure (3) is the mat material described in the present disclosure (1) or (2), wherein the glass transition temperature of the fibers forming the network is higher than the glass transition temperature of the organic matter constituting the plurality of bases.

[0281] The present disclosure (4) is a mat material in any combination with any one of the present disclosures (1) to (3), wherein the network is formed three-dimensionally.

[0282] The present disclosure (5) is a mat material in combination with any one of the present disclosures (1) to (4), wherein the fibers forming the network are composed of at least one of organic fibers and inorganic fibers.

[0283] The present disclosure (6) is a mat material characterized in that, on at least one of the first main surface and the second main surface of a base mat comprising inorganic fibers and having a first main surface and a second main surface, a network is formed by fiber bundles and single fibers formed by interweaving a plurality of fibers.

[0284] The present disclosure (7) is the mat material described in the present disclosure (6), comprising a plurality of the above-mentioned fiber bundles having mutually different extending directions,

[0285] The web is formed by a plurality of the fiber bundles and the single fibers.

[0286] The present disclosure (8) is the mat material described in the present disclosure (6) or (7), wherein at least one of the fiber bundle and the single fiber is bent.

[0287] The present disclosure (9) is a mat material in any combination with any one of the present disclosures (6) to (8), wherein the mesh is formed three-dimensionally.

[0288] The present disclosure (10) is a mat material in combination with any one of the present disclosures (6) to (9), wherein the fiber bundle and the single fiber are each composed of at least one of organic fibers and inorganic fibers.

[0289] The present disclosure (11) is an exhaust gas purification device, which comprises:

[0290] An exhaust gas treatment body, through which the exhaust gas flows;

[0291] A holding sealing material which is wound around the outer circumference of the exhaust gas treating body and used; and

[0292] a housing that accommodates the exhaust gas treatment body on which the holding sealing material is wound,

[0293] The exhaust gas purification device is characterized in that

[0294] The holding sealing material is a mat material in combination with any one of (1) to (10) of the present disclosure.

[0295] The present disclosure (12) is a method for manufacturing a mat material, characterized by comprising:

[0296] a substrate mat preparation step of preparing a substrate mat including inorganic fibers and having a first main surface and a second main surface;

[0297] a sheet preparation step of preparing a sheet including fibers extending in at least two directions;

[0298] a sheet material processing step of spreading hot-melt powder on the sheet material and heating the sheet material so that the hot-melt powder adheres to the sheet material; and

[0299] The sheet attaching step is to thermally press-bond the sheet to which the hot-melt powder is attached to at least one of the first main surface and the second main surface of the base mat, thereby attaching the sheet to the base mat.

[0300] (Example)

[0301] The following are examples that more specifically disclose the present invention. However, the present invention is not limited to these examples.

[0302] (Example 1)

[0303] The basis weight (weight of fiber per unit area) is 2400 g / m 2 , a large-sized substrate pad composed of inorganic fibers (mullite fibers).

[0304] As a large-sized sheet, a laminated sheet (nonwoven fabric) having fiber orientation in the longitudinal and transverse directions is prepared by laminating longitudinally oriented fibers in which PET fibers are oriented in the longitudinal direction and transversely oriented fibers in which PET fibers are oriented in the transverse direction. The PET fibers are oriented in the longitudinal direction, and the angle between the orientation direction of the longitudinally oriented fibers and the orientation direction of the transversely oriented fibers is approximately 90°. In addition, the sheet has an opening that is substantially square or rectangular. In addition, the basis weight (weighing) of the sheet is 10 g / m 2 .

[0305] The hot-melt powder is spread on the sheet and heated to adhere the hot-melt powder to the sheet. As the hot-melt powder, a hot-melt powder containing polyethylene (PE) as a main component is used.

[0306] The base material mat and the sheet material with the hot-melt powder attached thereto were bonded by thermal compression, and the sheet material was attached to the base material mat. The heating temperature was 130° C., the heating time was 40 seconds, and the pressing was performed at a constant pressure.

[0307] Thus, on the surface of the base mat, a network is formed by the plurality of bases made of an organic substance, and the longitudinally oriented fibers and the transversely oriented fibers extending from the plurality of bases in both the longitudinal and transverse directions, respectively.

[0308] In addition, the results are Figure 3 The attached bodies schematically shown in FIG. 1 are attached bodies of the same rectangular shape.

[0309] Afterwards, for the attached body, Figure 4 The arrangement schematically shown in FIG. 1 is subjected to the same punching process to obtain two types of mats (a first mat and a second mat).

[0310] In the first mat, the longitudinally oriented fibers of the sheet are oriented in parallel with the longitudinal direction of the mat, and in the second mat, the transversely oriented fibers of the sheet are oriented in parallel with the longitudinal direction of the mat.

[0311] (Example 2)

[0312] The basis weight (weight of fiber per unit area) is 2400 g / m 2 , a large-sized substrate pad composed of inorganic fibers (mullite fibers).

[0313] As a large-sized sheet, a laminated sheet (non-woven fabric) having fiber orientation in the longitudinal and transverse directions is prepared by laminating longitudinally oriented fibers in which PET fibers are oriented in the longitudinal direction and transversely oriented fibers in which PET fibers are oriented in the transverse direction. The PET fibers have an orientation in the direction in which they are arranged in the length direction, and the angle between the orientation direction of the longitudinally oriented fibers and the orientation direction of the transversely oriented fibers is approximately 90°. In addition, the longitudinally oriented fibers include fiber bundles and single fibers formed by interweaving a plurality of fibers, and the transversely oriented fibers include fiber bundles and single fibers formed by interweaving a plurality of fibers. In addition, the sheet has an opening that is substantially square or rectangular. In addition, the basis weight (weighing) of the sheet is 10 g / m 2 .

[0314] The hot-melt powder is spread on the sheet and heated to adhere the hot-melt powder to the sheet. As the hot-melt powder, a hot-melt powder containing polyethylene (PE) as a main component is used.

[0315] The base material mat and the sheet material with the hot-melt powder attached thereto were bonded by thermal compression, and the sheet material was attached to the base material mat. The heating temperature was 135° C., the heating time was 35 seconds, and the pressing was performed at a constant pressure.

[0316] Thus, on the surface of the base mat, a network is formed by the fiber bundles extending in both the longitudinal and transverse directions and the single fibers extending in both the longitudinal and transverse directions.

[0317] In addition, the results are Figure 7 The attached bodies schematically shown in FIG. 1 are attached bodies of the same rectangular shape.

[0318] Afterwards, for the attached body, Figure 8 The arrangement schematically shown in FIG. 1 is subjected to the same punching process to obtain two types of mats (a first mat and a second mat).

[0319] In the first mat, the longitudinally oriented fibers of the sheet are oriented in parallel with the longitudinal direction of the mat, and in the second mat, the transversely oriented fibers of the sheet are oriented in parallel with the longitudinal direction of the mat.

[0320] (Comparative Example 1)

[0321] In the same manner as in Examples 1 and 2, a large-sized substrate mat was produced.

[0322] As a large-sized sheet, a sheet is prepared by laminating and heat-melting a longitudinal web (a longitudinal web in which a polyolefin film extending in the longitudinal direction is split and has fibers oriented in the longitudinal direction) and a transverse web (a transverse web in which a polyolefin film extending in the transverse direction is split and has fibers oriented in the transverse direction).

[0323] The base material pad and the sheet material are heat-pressed without using an adhesive such as hot-melt powder. That is, the sheet material is heat-fused to the base material pad. As a result, a rectangular attached body having two longitudinal sides and two transverse sides is obtained.

[0324] Thereafter, the attached body was punched out in the same manner as in Examples 1 and 2 to obtain two types of mats (a first mat and a second mat).

[0325] In the first mat, the longitudinal web orientation direction (longitudinal direction) of the sheet is parallel to the long side direction of the mat, and in the second mat, the transverse web orientation direction (transverse direction) of the sheet is parallel to the long side direction of the mat.

[0326] (Presence or absence of cracks in the cushion material)

[0327] The two mat materials (the first mat material and the second mat material) manufactured in each of the examples and comparative examples were respectively wound to The cylindrical base.

[0328] When winding, the base material mat is on the base body side and the sheet material is on the outside.

[0329] Then, the occurrence of cracks in each wound mat was checked.

[0330] The results are shown in Table 1.

[0331] In the "Presence or Absence of Cracks", ○ indicates that no cracks have occurred, and × indicates that cracks have occurred.

[0332] [Table 1]

[0333]

[0334] From this result, it is understood that a network is formed on the surface of the base material mat by a plurality of bases composed of an organic substance and fibers extending from the plurality of bases in at least two directions, thereby preventing the occurrence of cracks when the mat is wound.

[0335] In addition, it was found that the fiber bundles formed by intertwining a plurality of fibers and the single fibers formed a network on the surface of the base mat, thereby preventing the occurrence of cracks when the mat was wound.

[0336] Fig.10 This is a photograph of the mat of Comparative Example 1.

[0337] like Fig.10 As shown, the mat of Comparative Example 1 had cracks generated in the portion surrounded by the dotted line after winding.

[0338] In the mat of Comparative Example 1, microscopic holes were formed in the fibers of the sheet after thermal compression bonding, and a plurality of fibers were fused to each other. Therefore, it is considered that the flexibility of the sheet was weakened, and cracks were generated after winding.

[0339] Description of Reference Numerals

[0340] 1. 201 No. 1 cushion material

[0341] 2.202 No. 2 cushion material

[0342] 10, 210 cushion material

[0343] 11. 211 convex part

[0344] 12, 212 concave part

[0345] 20, 120, 220, 320 base material pad

[0346] 21, 121, 221, 321 The first main surface of the substrate pad

[0347] 22, 222 second main surface of the substrate pad

[0348] 130, 330 sheets

[0349] 31, 231 longitudinally oriented fibers

[0350] 32, 232 Transversely oriented fibers

[0351] 40 Exhaust gas treatment body

[0352] 41 Channel

[0353] 42 Channel wall

[0354] 43 Sealing material

[0355] 50 Shell

[0356] 60 Maintain sealing material

[0357] 70 Network

[0358] 71, 273 base

[0359] 72 Fiber

[0360] 100 Exhaust gas purification device

[0361] 150, 350 Attachment

[0362] 270 Mesh

[0363] 271 Fiber bundle

[0364] 271a Longitudinally oriented fiber bundle

[0365] 271b Transversely oriented fiber bundle

[0366] 271c Curved fiber bundle

[0367] 272 single fiber

[0368] 272a Longitudinally oriented single fiber

[0369] 272b Transversely oriented single fiber

[0370] 272c Bent single fiber

Claims

1. A mat material, characterized in that: A base mat including inorganic fibers and having a first main surface and a second main surface has a network formed on at least one of the first and second main surfaces by a plurality of bases composed of organic matter and fibers extending from the plurality of bases in at least two directions.

2. The mat material according to claim 1, wherein: The maximum width of each of the plurality of bases is greater than the width of the fibers forming the network.

3. The mat material according to claim 1 or 2, wherein: The glass transition temperature of the fibers forming the network is higher than the glass transition temperature of the organic matter constituting the plurality of bases.

4. The mat material according to any one of claims 1 to 3, wherein The network is formed three-dimensionally.

5. The mat material according to any one of claims 1 to 4, wherein The fibers forming the network are composed of at least one of organic fibers and inorganic fibers.

6. A mat material, characterized in that: On at least one of the first and second main surfaces of a base mat including inorganic fibers and having a first and second main surfaces, a network is formed by fiber bundles and single fibers formed by interweaving a plurality of fibers.

7. The mat material according to claim 6, comprising a plurality of fiber bundles extending in different directions from each other, The web is formed by a plurality of the fiber bundles and the single fibers.

8. The mat material according to claim 6 or 7, wherein: At least one of the fiber bundle and the single fiber is bent.

9. The mat material according to any one of claims 6 to 8, wherein The mesh is formed three-dimensionally.

10. The mat material according to any one of claims 6 to 9, wherein The fiber bundle and the single fiber are each composed of at least one of organic fibers and inorganic fibers.

11. An exhaust gas purification device, comprising: An exhaust gas treatment body, through which the exhaust gas flows; a holding sealing material which is wound around the outer circumference of the exhaust gas treating body and is used; and a housing that accommodates the exhaust gas treatment body around which the holding sealing material is wound, The exhaust gas purification device is characterized in that The holding sealing material is the mat material according to any one of claims 1 to 10.

12. A method for manufacturing a mat material, characterized in that: have: a substrate mat preparation step of preparing a substrate mat including inorganic fibers and having a first main surface and a second main surface; a sheet preparation step of preparing a sheet including fibers extending in at least two directions; a sheet material processing step of spreading hot-melt powder on the sheet material and heating the sheet material so that the hot-melt powder adheres to the sheet material; and The sheet attaching step is to thermally press-bond the sheet to which the hot-melt powder is attached to at least one of the first main surface and the second main surface of the base mat, thereby attaching the sheet to the base mat.

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