Gasket, exhaust gas purifying device, and method for manufacturing gasket

Abstract

The present invention relates to a gasket having: a base gasket comprising inorganic fibers, having a first main surface and a second main surface; and a sheet provided on at least one of the first main surface and the second main surface, the gasket being characterized in that the sheet is a laminated sheet in which longitudinally oriented fibers and transversely oriented fibers are laminated, the sheet has an opening surrounded by the longitudinally oriented fibers and the transversely oriented fibers, and the average opening area of the sheet is greater than 0 mm 2 2 and 0.7 mm 2 2 or less.

Description

Technical Field

[0001] This invention relates to padding materials, waste gas purification devices, and methods for manufacturing padding materials. Background Technology

[0002] Exhaust gases from internal combustion engines such as diesel engines contain particulate matter (PM), and in recent years, the environmental and human health risks associated with PM have become a concern. Furthermore, because exhaust gases also contain harmful gases such as CO, HC, and NOx, there are concerns about the potential impact of these harmful components on the environment and human health.

[0003] Therefore, various designs for exhaust gas purification devices, which capture PM and purify harmful gas components from exhaust gases, have been proposed. These devices consist of an exhaust gas treatment body (composed of porous ceramics such as silicon carbide and cordierite), a shell (cylindrical component) housing the exhaust gas treatment body, and a sealing material installed between the exhaust gas treatment body and the shell. The main purpose of this sealing material is to prevent damage to the exhaust gas treatment body from contact with the shell covering its periphery due to vibrations or impacts caused by vehicle movement, etc.; to prevent exhaust gas leakage between the exhaust gas treatment body and the shell; and so on.

[0004] As a sealing material used in such applications, a gasket made of inorganic fibers is used. Gaskets made of inorganic fibers are also used for heat insulation and sound insulation applications, such as when wrapped around piping in automobiles.

[0005] Patent Document 1 discloses a composite pad used for winding around a small-diameter exhaust gas treatment body (catalytic converter). As a composite pad, it is disclosed that the pad is composed of inorganic fibers, a binder, and a flexible sheet on at least one side of a layer of inorganic fibers.

[0006] In addition, Patent Document 2 discloses a sealing material in which a protective sheet with anisotropic elongation in the plane is provided on the surface of a pad substrate.

[0007] In addition, Patent Document 3 discloses a sealing material in which a sheet having an opening in at least a portion of its surface is disposed on at least one of a first main surface and a second main surface of a substrate.

[0008] In addition, Patent Document 4 discloses a pad material in which oriented organic sheets are disposed on the surface of a substrate pad. The organic sheets are formed by stacking at least two of a first organic sheet and a second organic sheet, wherein the orientation direction of the first organic sheet is different from that of the second organic sheet.

[0009] Existing technical documents

[0010] Patent documents

[0011] Patent Document 1: Japanese Patent Publication No. 2001-521847

[0012] Patent Document 2: Japanese Patent Application Publication No. 2008-51004

[0013] Patent Document 3: Japanese Patent Application Publication No. 2009-85092

[0014] Patent Document 4: Japanese Patent Application Publication No. 2020-84798 Summary of the Invention

[0015] The problem that the invention aims to solve

[0016] Patent documents 1, 2 and 4 provide flexible sheets or the like to prevent the padding material from breaking during winding.

[0017] In addition, in Patent Document 3, a sheet is provided to prevent the inorganic fibers contained in the substrate from scattering.

[0018] As a method for manufacturing such padding materials, a punching method (also known as punching process) has been used, which utilizes a punching die with a punching edge.

[0019] In this process, sheet-like components made of inorganic fibers and large-sized attachments with flexible sheets are prepared. The attachments are punched, thereby obtaining a large quantity of padding material through a single punching process.

[0020] The padding material has a long side direction that serves as the winding direction, and a short side direction that is orthogonal to the long side direction.

[0021] When such a pad is obtained from a single large-sized adhesive body, the parts where the pad is punched in the longitudinal direction of the adhesive body as the long side of the pad, and the parts where the pad is punched in the transverse direction of the adhesive body as the long side of the pad, are combined to obtain as much pad material as possible from a single large-sized adhesive body.

[0022] In this case, two types of padding materials can be obtained with different orientation relationships between the longitudinal and transverse directions of the attached body and the long side direction of the padding material.

[0023] Here, when using sheets with anisotropic elongation, two types of pads with different relationships between the orientation of the long side of the pad and the tensile strength of the sheet can be obtained.

[0024] Specifically, two types of pads can be obtained: pads in which the long side of the pad is oriented in the same direction as the tensile strength of the sheet (hard pads) and pads in which the long side of the pad is oriented in the same direction as the tensile strength of the sheet (easy pads).

[0025] Strong padding material refers to the following padding material: Since the direction of the long side of the padding material is consistent with the direction of the tensile strength of the sheet, when the long side of the padding material is used as the winding direction to wind the padding material to the exhaust gas treatment body, the resistance caused by the tensile strength of the sheet is strong, and force is required during winding.

[0026] On the other hand, weak padding material refers to the following padding material: since the orientation of the long side of the padding material is consistent with the direction of the weak tensile strength of the sheet, when the long side of the padding material is used as the winding direction to wind the padding material to the exhaust gas treatment body, the resistance caused by the tensile strength of the sheet is weak, and no force is required during winding.

[0027] For padding materials, their product standards require a certain degree of winding ability; padding materials whose winding ability deviates from the standard value are considered defective.

[0028] Therefore, when two types of padding materials with different winding properties, strong padding material and weak padding material, are obtained from a single large-sized attachment, one type of padding material is more likely to be considered defective.

[0029] Given this situation, even when two types of padding materials are obtained from a single large-sized adhesive, it is preferable that the wrapping properties of the two padding materials be equal within the standard value.

[0030] Furthermore, even if sheets such as flexible sheets are provided, if the opening area of ​​the sheets is large, the pad material may break when it is wrapped around the exhaust gas treatment body.

[0031] The present invention was made in view of the following problems, and its object is to provide a pad material that is configured such that its winding performance is stably within a standard value and that it is able to suppress breakage during winding.

[0032] Methods for solving problems

[0033] The padding material of the present invention comprises: a substrate pad containing inorganic fibers and having a first main surface and a second main surface; and a sheet disposed on at least one of the first main surface and the second main surface. The padding material is characterized in that the sheet is a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers, the sheet has openings surrounded by the longitudinally oriented fibers and the transversely oriented fibers, and the average opening area of ​​the sheet is greater than 0 mm². 2 / each and 0.7mm 2 / or less.

[0034] The padding material of the present invention has a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers as the sheet, thereby reducing the anisotropy of the tensile strength of the sheet, thus making the padding material have a structure in which the winding performance is stably within the standard value.

[0035] Furthermore, in the pad material of the present invention, the sheet has openings surrounded by the longitudinally oriented fibers and the transversely oriented fibers, and the average opening area of ​​the sheet is greater than 0 mm. 2 / each and 0.7mm 2 With fewer than one sheet, the adhesion between the sheet and the substrate pad is increased, thereby suppressing the occurrence of cracks during pad winding.

[0036] In the padding material of the present invention, if the average open area of ​​the sheet exceeds 0.7 mm... 2 If each piece is not properly wound, it will be difficult to prevent cracking during the winding of the padding material.

[0037] In the padding material of the present invention, the angle between the orientation direction of the longitudinally oriented fibers and the orientation direction of the transversely oriented fibers is preferably 60° or more and 120° or less.

[0038] This further reduces the anisotropy of the tensile strength of the sheet, thus enabling the fabrication of a pad with more stable winding properties.

[0039] In the padding material of the present invention, the open porosity of the above-mentioned sheet is preferably greater than 0% and less than 40%.

[0040] This allows for more effective suppression of cracks during the winding of the padding material.

[0041] In the padding material of the present invention, if the porosity of the sheet is greater than 40%, there is a risk that the breakage during the winding of the padding material cannot be effectively suppressed.

[0042] In the padding material of the present invention, the sheet is preferably composed of at least one of organic and inorganic materials.

[0043] This allows for more effective suppression of cracks during the winding of the padding material.

[0044] The aforementioned sheet material is more preferably composed of organic matter.

[0045] This can further and more effectively suppress the occurrence of cracks during the winding of the padding material.

[0046] In the padding material of the present invention, the sheet material is preferably polyethylene terephthalate, polyethylene or polypropylene.

[0047] This allows for more effective suppression of cracks during the winding of the padding material.

[0048] In the padding material of the present invention, the aforementioned substrate pad preferably further comprises at least one of an inorganic binder and an organic binder.

[0049] When the aforementioned substrate pad contains an inorganic binder, it can improve the holding force of the waste gas treatment body, etc.

[0050] This is because when the aforementioned substrate pad contains an organic binder, it can prevent the inorganic fibers contained in the substrate pad from scattering.

[0051] The exhaust gas purification device of the present invention comprises an exhaust gas treatment body for circulating exhaust gas, a retaining and sealing material used to wrap around the outer periphery of the exhaust gas treatment body, and an outer shell exhaust gas containing the exhaust gas of the exhaust gas treatment body to which the retaining and sealing material is wrapped, characterized in that the retaining and sealing material is the pad material of the present invention.

[0052] As described above, the padding material of the present invention can suppress the occurrence of cracks during winding. Therefore, the exhaust gas purification device of the present invention can suppress the leakage of untreated exhaust gas from cracks in the padding material.

[0053] The method for manufacturing the pad material of the present invention includes the following steps: a substrate pad preparation step, preparing a substrate pad comprising inorganic fibers and having a first main surface and a second main surface; a sheet preparation step, preparing a sheet; and a sheet placement step, placing the sheet on at least one of the first main surface and the second main surface of the substrate pad. The manufacturing method is characterized in that the sheet is a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers, the sheet has openings surrounded by the longitudinally oriented fibers and the transversely oriented fibers, and the average opening area of ​​the sheet is greater than 0 mm². 2 / each and 0.7mm 2 / or less.

[0054] In the method for manufacturing the padding material of the present invention, a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers is used as the sheet, thereby reducing the anisotropy of the tensile strength of the sheet, thereby enabling the production of multiple padding materials with a winding performance within the standard value from a single large-sized attachment.

[0055] Furthermore, in the method for manufacturing the pad material of the present invention, the sheet material has openings surrounded by the longitudinally oriented fibers and the transversely oriented fibers, and the average opening area of ​​the sheet material is greater than 0 mm. 2 / each and 0.7mm 2 With fewer than one sheet, the sheet can be positioned in a state where it is tightly sealed to the substrate, thereby suppressing the occurrence of breakage when the pad is wound.

[0056] In the method for manufacturing the padding material of the present invention, if the average open area of ​​the sheet is greater than 0.7 mm... 2 If each piece is not properly wound, it will be difficult to prevent cracking during the winding of the padding material. Attached Figure Description

[0057] Figure 1 This is a perspective view schematically showing an example of a padding material.

[0058] Figure 2 It is shown schematically. Figure 1 The enlarged 3D view of the sheet shown.

[0059] Figure 3 yes Figure 2 The top view of the sheet shown.

[0060] Figure 4 yes Figure 2 The side view of the sheet shown.

[0061] Figure 5 This is a perspective view schematically illustrating an example of an attachment.

[0062] Figure 6 This is a schematic top view illustrating the process of obtaining two types of padding materials through punching.

[0063] Figure 7 This is a schematic cross-sectional view illustrating an example of the exhaust gas purification device of the present invention.

[0064] Figure 8 This is an enlarged top view schematically showing the sheet of Comparative Example 1.

[0065] Figure 9 This is a photograph of the padding material in Comparative Example 2. Detailed Implementation

[0066] The following provides a detailed description of the mat material, the waste gas purification device, and the method for manufacturing the mat material according to the present invention. However, the present invention is not limited to the following configuration and can be appropriately modified and applied without changing the essential points of the present invention. It should be noted that solutions combining two or more of the preferred configurations of the present invention described below are also part of the present invention.

[0067] The padding material of the present invention comprises: a substrate pad containing inorganic fibers and having a first main surface and a second main surface; and a sheet disposed on at least one of the first main surface and the second main surface. The padding material is characterized in that the sheet is a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers, the sheet has openings surrounded by the longitudinally oriented fibers and the transversely oriented fibers, and the average opening area of ​​the sheet is greater than 0 mm². 2 / each and 0.7mm 2 / or less.

[0068] Figure 1 This is a perspective view schematically showing an example of a padding material.

[0069] Figure 1 The pad material 10 shown has a structure formed by stacking a sheet 30 on the first main surface 21 of a substrate pad 20 having a first main surface 21 and a second main surface 22.

[0070] On the long side of the pad material 10 ( Figure 1 A protrusion 11 is formed at one end (the direction indicated by the double arrow L) and a recess 12 is formed at the other end (the second end).

[0071] The protrusion 11 and the recess 12 are formed by stacking the protrusions and recesses respectively provided on the substrate pad 20 and the sheet 30.

[0072] When the padding material is wound around a waste gas purification device, waste gas treatment body, or exhaust pipe with a cylindrical outer perimeter, the convex and concave parts of the padding material become a shape that fits perfectly into each other.

[0073] It should be noted that, Figure 1 In the diagram, the direction indicated by the double arrow W is the short side direction of the padding material, and the direction indicated by the double arrow T is the thickness direction of the padding material.

[0074] It should be noted that, Figure 1 The diagram shows a case where the sheet 30 is provided only on the first main surface 21 of the substrate pad 20, but the sheet 30 can also be provided on both the first main surface 21 and the second main surface 22 of the substrate pad 20. In addition, the sheet 30 can also be provided on the side surface of the substrate pad 20, in addition to the first main surface 21 and / or the second main surface 22 of the substrate pad 20.

[0075] Figure 2 It is shown schematically. Figure 1 The enlarged 3D view of the sheet shown. Figure 3 yes Figure 2 The top view of the sheet shown. Figure 4 yes Figure 2 The side view of the sheet shown.

[0076] It should be noted that, Figures 2-4 To illustrate the configuration relationship between the sheet 30 and the substrate pad 20, the substrate pad 20 is also represented by a dashed line.

[0077] like Figures 2-4 As shown, sheet 30 is a laminated sheet formed by laminating longitudinally oriented fibers 31 and transversely oriented fibers 32.

[0078] The orientation direction of the longitudinally oriented fiber 31 is longitudinal and parallel to the long side direction of the pad material 10 (indicated by the double arrow L).

[0079] The orientation direction of the transversely oriented fiber 32 is transverse and parallel to the short side direction of the pad material 10 (in the direction indicated by the double arrow W).

[0080] Figures 2-4 As an example, the case shown illustrates a situation where the angle between the orientation direction of the longitudinally oriented fiber 31 and the orientation direction of the transversely oriented fiber 32 is approximately 90°.

[0081] Sheet 30 is a nonwoven fabric with fiber orientation in both longitudinal and transverse directions, formed by laminating longitudinally oriented fibers 31 and transversely oriented fibers 32.

[0082] Sheet 30 is made using a manufacturing process that involves directly spinning raw materials. The long fibers are stretched in all directions to make them evenly oriented (arranged) in all directions.

[0083] In addition, the fibers in sheet 30 are arranged in a uniform manner, resulting in high basis weight uniformity and minimal fiber overlap, thus creating a smooth structure.

[0084] The longitudinally oriented fibers 31 and the transversely oriented fibers 32 are joined together.

[0085] There are no particular limitations on the bonding method of longitudinally oriented fibers 31 and transversely oriented fibers 32. Examples include water jetting, needle punching, hot air (through air) bonding, hot embossing, adhesive bonding, stitching, ultrasonic sealing, and induction heating sealing.

[0086] like Figure 2 and Figure 3 As shown, sheet 30 is a perforated nonwoven fabric with openings 35 surrounded by longitudinally oriented fibers 31 and transversely oriented fibers 32.

[0087] like Figure 3 As shown, each opening 35 is roughly square or rectangular, divided by longitudinally oriented fibers 31 and transversely oriented fibers 32.

[0088] It should be noted that, in Figures 2-4 The diagram shows the case where longitudinally oriented fibers 31 and transversely oriented fibers 32 are laminated layer by layer, but the number of layers of longitudinally oriented fibers 31 and transversely oriented fibers 32 is not particularly limited, and longitudinally oriented fibers 31 and transversely oriented fibers 32 can also be laminated alternately to a total of 3 or more layers.

[0089] in addition, Figures 2-4 The diagram shows the case where these layers are laminated from the substrate pad 20 side in the order of longitudinally oriented fibers 31 and transversely oriented fibers 32, but these layers can also be laminated from the substrate pad 20 side in the order of transversely oriented fibers 32 and longitudinally oriented fibers 31.

[0090] The following is a detailed explanation of their composition.

[0091] The substrate pad constituting the padding material of the present invention is made of inorganic fibers. The inorganic fibers are not particularly limited and can be alumina-silica fibers, alumina fibers, silica fibers, etc. Alternatively, glass fibers or biosoluble fibers can also be used. The fibers can be modified according to the required properties of the padding material, such as heat resistance and wind erosion resistance. It is preferable to use fibers with a diameter and length that meet the environmental standards of various countries.

[0092] Inorganic fibers with low crystallinity alumina are preferred, and inorganic fibers with low crystallinity alumina composed of mullite are more preferred. Furthermore, inorganic fibers containing spinel-type compounds are even more preferred.

[0093] The substrate pad has a long side direction that serves as the winding direction, and a short side direction that is orthogonal to the long side direction.

[0094] In the substrate pad, it is preferable that a protrusion is formed at one end, i.e., the first end, on the long side side of the substrate pad, and a recess is formed at the other end, i.e., the second end. The protrusion and recess of the substrate pad are preferably shaped such that they fit together precisely when the pad material is wound around a waste gas purification device, waste gas treatment body, or exhaust pipe with a cylindrical outer periphery.

[0095] Alternatively, the substrate pad can also be a shape without protrusions and recesses.

[0096] The thickness of the aforementioned substrate pad is preferably 2 to 30 mm.

[0097] If the thickness of the substrate pad is less than 2mm, it is too thin, thus reducing its thermal insulation and sound insulation performance. On the other hand, if the thickness of the substrate pad is greater than 30mm, its flexibility is reduced, which decreases the assemblability of the components to be assembled.

[0098] The bulk density of the aforementioned substrate pad is not particularly limited, but is preferably 0.05–0.30 g / cm³. 3 .

[0099] If the bulk density of the substrate pad is less than 0.05 g / cm³ 3 If the inorganic fiber entanglement weakens, the inorganic fibers become easier to peel off, making it difficult to maintain the substrate pad's shape as specified. On the other hand, if the substrate pad's bulk density exceeds 0.30 g / cm³... 3 If the substrate pad hardens, the assemblability of the component to be assembled decreases, and the substrate pad is prone to cracking.

[0100] The sheet constituting the pad material of the present invention is a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers.

[0101] Therefore, the sheet material has the same properties in all directions, enabling it to exhibit isotropic tensile strength. As a result, the padding material of the present invention is a padding material constructed in a manner that ensures its winding stability is within standard values.

[0102] The direction in which the fibers that make up the longitudinally oriented fibers are arranged along their length is called the orientation direction of the longitudinally oriented fibers, and the direction in which the fibers that make up the transversely oriented fibers are arranged along their length is called the orientation direction of the longitudinally oriented fibers.

[0103] Preferably, the fibers constituting the longitudinally oriented fibers and the transversely oriented fibers are long fibers and filaments.

[0104] The long fiber filament is preferably a fiber that is longer than the length of common short fibers (e.g., 10-50 mm), and the average fiber length of the filament is preferably longer than 100 mm, and more preferably several hundred mm or more.

[0105] Long fiber filaments can be continuous long fibers.

[0106] The average fiber diameter of the fibers constituting the longitudinally oriented fibers and the transversely oriented fibers is usually less than 10 μm, preferably around 5 μm, in the main constituting filaments.

[0107] The sheet has openings surrounded by longitudinally oriented fibers and transversely oriented fibers. That is, when viewed from above, there are a large number of gaps in the sheet where neither longitudinally nor transversely oriented fibers exist.

[0108] The shape of the openings in the sheet is not particularly limited, but it is preferred to be substantially square or rectangular.

[0109] In addition, the sheet material has a large number of openings, which can contain openings of various shapes.

[0110] If the openings in the sheet are large, the adhesion between the sheet and the substrate pad will deteriorate, and cracks will occur when the pad is wound. Therefore, it is preferable to have the openings in the sheet as small as possible.

[0111] Specifically, the average opening area of ​​the sheet is greater than 0 mm. 2 / each and 0.7mm 2 / or less.

[0112] As a result, the adhesion between the sheet and the substrate pad is increased, thus suppressing the occurrence of cracks during pad winding.

[0113] The average opening area of ​​the sheet is preferably 0.0001 mm. 2 / or more, 0.5mm 2 / or less, preferably 0.0001mm 2 / or more, 0.1mm 2 / or less, further preferably 0.0001mm 2 / or more, 0.01mm 2 / or less.

[0114] The average opening area of ​​the sheet can be calculated as follows.

[0115] Take magnified photographs of the sheet using a microscope, import the magnified photographs into any graphics drawing software, draw rectangles that approximate each opening of the sheet, compare the rectangles with a reference rectangle whose area is known, and calculate the area of ​​the opening.

[0116] Then, the average of all calculated opening areas is taken as the average opening area of ​​the sheet (the average area of ​​each opening).

[0117] The sheet material preferably has substantially the same planar shape as the substrate pad. That is, when viewed from above, the arrangement areas of the sheet material and the substrate pad are preferably substantially the same.

[0118] In addition, the sheet is preferably attached to a substrate pad. The attachment of the sheet to the substrate pad can be done, for example, by using an adhesive, or it can be done without using an adhesive by heat-pressing (e.g., heat lamination) the sheet itself.

[0119] The basis weight of the sheet is not particularly limited, but is preferably 5 g / m³. 2 Above, 100g / m 2 The following is more preferably 5g / m 2 Above, 50g / m 2 The following is a further preferred value: 5g / m 2 Above, 30g / m 2 the following.

[0120] It should be noted that the basis weight of the sheet mentioned here refers to the basis weight of each individual sheet.

[0121] The angle between the orientation direction of the longitudinally oriented fibers and the orientation direction of the transversely oriented fibers is not particularly limited, but is preferably 60° or more and 120° or less, more preferably 70° or more and 110° or less, even more preferably 80° or more and 100° or less, and particularly preferably substantially 90°.

[0122] The angle between the orientation direction of the longitudinally oriented fibers and the orientation direction of the transversely oriented fibers can be calculated as follows.

[0123] A magnified photograph of the sheet was taken using a microscope and imported into any graphics drawing software. Then, rectangles approximating the openings in the sheet were drawn, and the angles of these openings were calculated. From this, the angle between the orientation directions of the longitudinally oriented fibers and the transversely oriented fibers was calculated.

[0124] It should be noted that there is no particular limitation on the relationship between the orientation direction of the longitudinal and transverse fibers and the long and short sides of the padding material. Preferably, the orientation direction of one of the longitudinal and transverse fibers is parallel to the long side of the padding material, and the orientation direction of the other of the longitudinal and transverse fibers is parallel to the short side of the padding material.

[0125] The open area ratio of the sheet is preferably greater than 0% and less than 40%, more preferably more than 5% and less than 30%, and even more preferably more than 10% and less than 25%.

[0126] The open area ratio of a sheet can be calculated as follows: the area of ​​the open area is calculated by measuring the average open area of ​​the sheet, and the total area of ​​all the calculated open areas is calculated as a percentage of the area occupied by the sheet in the magnified photograph. The open area ratio is thus calculated.

[0127] The sheet material is preferably composed of at least one of organic and inorganic substances.

[0128] For example, longitudinally oriented fibers can be composed of organic fibers and / or inorganic fibers, and transversely oriented fibers can also be composed of organic fibers and / or inorganic fibers. The materials of longitudinally oriented fibers and transversely oriented fibers can be different, but generally, when longitudinally oriented fibers are composed of organic fibers, transversely oriented fibers are also composed of organic fibers, and when longitudinally oriented fibers are composed of inorganic fibers, transversely oriented fibers are also composed of inorganic fibers.

[0129] The sheet material is more preferably composed of organic matter.

[0130] For example, both longitudinally oriented fibers and transversely oriented fibers can be composed of organic fibers.

[0131] More specifically, suitable materials for sheet materials include polyethylene terephthalate (PET), polyethylene (PE), and polypropylene (PP).

[0132] In the padding material of the present invention, the aforementioned substrate pad preferably further comprises at least one of an inorganic binder and an organic binder.

[0133] The amount of inorganic binder (weight of inorganic binder / weight of padding material) can be greater than 0% by weight and less than 15% by weight, for example.

[0134] The amount of organic binder (weight of organic binder / weight of padding material) can be, for example, greater than 0% by weight and less than 15% by weight.

[0135] As an inorganic binder, aluminum sol, silica sol, etc. can be used.

[0136] As organic binders, preferred materials include acrylic resins, acrylate emulsions, rubber emulsions, water-soluble organic polymers such as carboxymethyl cellulose or polyvinyl alcohol, thermoplastic resins such as styrene resins, and thermosetting resins such as epoxy resins.

[0137] Next, the method for manufacturing the padding material of the present invention will be described.

[0138] The method for manufacturing the padding material of the present invention includes the following steps: a substrate pad preparation step, preparing a substrate pad comprising inorganic fibers and having a first main surface and a second main surface; a sheet preparation step, preparing a sheet; and a sheet placement step, placing the sheet on at least one of the first main surface and the second main surface of the substrate pad. The method for manufacturing the padding material is characterized in that the sheet is a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers, the sheet has openings surrounded by the longitudinally oriented fibers and the transversely oriented fibers, and the average opening area of ​​the sheet is greater than 0 mm². 2 / each and 0.7mm 2 / or less.

[0139] In the method for manufacturing the padding material of the present invention, it is preferable to manufacture two types of padding materials. The two types of padding materials are a first padding material and a second padding material, and either padding material is a padding material of the present invention.

[0140] In the method for manufacturing the pad material of the present invention, a substrate pad having a first main surface and a second main surface, and a sheet material are first prepared.

[0141] The structure and properties of the substrate pads and sheets prepared herein are the same as those of the substrate pads and sheets described in the pads of this invention, therefore detailed descriptions are omitted here.

[0142] However, the substrate pad and sheet prepared here are preferably large-sized sheets that can be obtained by punching multiple sheets of the pad material of the present invention.

[0143] The substrate pad can be obtained by various methods, such as by papermaking or needle punching.

[0144] In the case of copying, it can be manufactured, for example, by the following method.

[0145] Inorganic fibers are split open and dispersed in a solvent to form a mixture. The mixture is poured into a molding apparatus with a filter screen on the bottom surface, and the solvent in the mixture is removed to obtain inorganic fiber aggregates. The inorganic fiber aggregates are then dried to obtain the substrate pad.

[0146] In the case of acupuncture, it may be manufactured, for example, by the following method.

[0147] An inorganic fiber precursor with an average fiber diameter of 3–10 μm is produced by spinning a spinning mixture using an alkaline aluminum chloride aqueous solution and silica sol as raw materials. Next, the inorganic fiber precursor is compressed to produce a continuous substrate pad of a specified size, which is then subjected to a firing process to obtain the substrate pad. Needling is performed at any stage before or after this firing process to interweave the inorganic fibers.

[0148] Sheets are manufactured, for example, by the following methods.

[0149] First, a raw material (e.g., resin) is melt-spun using a nonwoven fabric spinning device such as meltblown nonwoven fabric or spunbond nonwoven fabric. Next, fibers are arranged and stretched in both the longitudinal (MD) and transverse (CD) directions to create a longitudinally stretched web (formed by longitudinally stretching a continuous body of long fiber filaments) and a transversely stretched web (formed by transversely stretching a continuous body of the same long fiber filaments). Then, the longitudinally stretched web and the transversely stretched web are laminated together to create a sheet (laminated sheet) formed by laminating longitudinally oriented fibers and transversely oriented fibers.

[0150] It should be noted that, as mentioned above, the joining methods for longitudinal and transverse stretched meshes can include, for example, water jetting, needle punching, hot air method, hot embossing, adhesive bonding, stitching, ultrasonic sealing, and induction heating sealing.

[0151] Sheets manufactured in this way have openings surrounded by longitudinally oriented fibers and transversely oriented fibers, with an average opening area greater than 0 mm². 2 / each and 0.7mm 2 / or less.

[0152] Next, a sheet is disposed on at least one of the first main surface and the second main surface of the substrate pad.

[0153] At this point, it is preferable to attach a large sheet to a large substrate pad to obtain an attachment.

[0154] The attachment can be done, for example, with the aid of an adhesive, or it can be done without the use of an adhesive by heat-pressing the sheet itself (e.g., heat lamination).

[0155] Figure 5 This is a perspective view schematically illustrating an example of an attachment.

[0156] The attach body 150 is formed by attaching a large sheet 130 to the first main surface 121 of a large substrate pad 120, and is a rectangular sheet with two longitudinal sides and two transverse sides.

[0157] Sheet 130 is a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers. The orientation direction of the longitudinally oriented fibers of sheet 130 is longitudinal and parallel to the two longitudinal sides of the attach body 150. The orientation direction of the transversely oriented fibers of sheet 130 is transverse and parallel to the two transverse sides of the attach body 150.

[0158] In sheet 130, the angle between the orientation direction of the longitudinally oriented fibers and the orientation direction of the transversely oriented fibers is particularly preferably about 90°, but this angle is not particularly limited.

[0159] From the perspective of reducing the anisotropy of the tensile strength of the sheet, it is preferable to have an angle of 60° or more and 120° or less, more preferably 70° or more and 110° or less, even more preferably 80° or more and 100° or less, and particularly preferably substantially 90°.

[0160] Next, by punching the attachment, a pad material of a specified shape can be produced.

[0161] In the method for manufacturing the padding material of the present invention, a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers is used as the sheet material. Therefore, the anisotropy of the tensile strength of the sheet material can be reduced, thereby enabling the production of multiple padding materials with a winding performance within the standard value from a single large-sized attachment.

[0162] Furthermore, in the method for manufacturing the padding material of the present invention, the sheet has openings surrounded by longitudinally oriented fibers and transversely oriented fibers, and the average opening area of ​​the sheet is greater than 0 mm². 2 / each and 0.7mm 2 With fewer than one sheet, the sheet can be positioned in a state where it is tightly sealed to the substrate, thereby suppressing the occurrence of breakage when the pad is wound.

[0163] In the punching process of the attachment, it is preferable to perform the process of obtaining a first pad material in which the longitudinal direction of the attachment is the long side direction of the pad material and the transverse direction of the attachment is the short side direction of the pad material, and a second pad material in which the transverse direction of the attachment is the long side direction of the pad material and the longitudinal direction of the attachment is the short side direction of the pad material, thereby obtaining two kinds of pad materials, namely the first pad material and the second pad material.

[0164] Figure 6 This is a schematic top view illustrating the process of obtaining two types of padding materials through punching.

[0165] for Figure 6 The attached body 150 shown is punched to obtain two types of pad materials.

[0166] Figure 6 The left side shows the orientation direction of the longitudinally oriented fibers that make up the sheet. Figure 6 The longitudinal direction shown refers to the long side direction of the padding material and the orientation direction of the transverse fibers of the sheet. Figure 6The transverse direction shown is the first pad material 1 in the short side direction of the pad material.

[0167] in addition, Figure 6 The right side shows the orientation direction of the transversely oriented fibers that make up the sheet. Figure 6 The transverse direction shown refers to the long side direction of the padding material and the orientation direction of the longitudinally oriented fibers of the sheet material. Figure 6 The longitudinal direction shown is the second pad material 2 in the direction of the short side of the pad material.

[0168] In both the first and second padding materials 1 and 2, the number and density of fibers (longitudinal or transverse) in the sheet oriented along the long side of the padding material are the same as those (transverse or longitudinal) in the sheet oriented along the short side of the padding material, thus exhibiting approximately the same tensile strength and winding properties. That is, a pad with the smallest difference in winding properties between the first and second padding materials is obtained, and the winding properties of either padding material are within the standard value.

[0169] Therefore, it can be said that multiple pieces of padding material with standard wrapping properties can be obtained from a single large-sized adhesive.

[0170] In addition, during the punching process, it is preferable that the orientation direction of one of the longitudinally oriented fibers and the transversely oriented fibers of the sheet is parallel to the long side direction of the first pad material and parallel to the short side direction of the second pad material.

[0171] In addition, it is preferable that the orientation direction of the other of the longitudinally oriented fibers and the transversely oriented fibers of the sheet is parallel to the short side direction of the first pad material and parallel to the long side direction of the second pad material.

[0172] Figure 6 The punching direction shown is the direction that satisfies the above conditions.

[0173] As explained so far, in the method for manufacturing the padding material of the present invention, a first padding material and a second padding material are obtained, and the winding properties of the first padding material and the second padding material are affected by both the orientation direction of the longitudinally oriented fibers of the sheet and the orientation direction of the transversely oriented fibers of the sheet.

[0174] Because the orientation direction of longitudinally oriented fibers is different from that of transversely oriented fibers, these orientation directions have different effects on the winding properties of the padding material.

[0175] In either the first or the second padding material, the winding property of the padding material is determined not only by the orientation direction of the longitudinally oriented fibers, but also by the orientation direction of the transversely oriented fibers. Therefore, the influence of the orientation direction of one of them on the winding property of the padding material is mitigated.

[0176] In this way, since the difference in winding properties between the first and second pads with different punching directions is reduced, the winding properties of both the first and second pads can be kept within the standard value.

[0177] The exhaust gas purification device of the present invention will be described below.

[0178] The exhaust gas purification device of the present invention comprises: an exhaust gas treatment body for circulating exhaust gas; a retaining and sealing material used to wrap around the outer periphery of the exhaust gas treatment body; and a shell for housing the exhaust gas treatment body on which the retaining and sealing material is wrapped, wherein the exhaust gas purification device is characterized in that the retaining and sealing material is the pad material of the present invention.

[0179] As described above, the gasket material of the present invention can suppress the occurrence of cracks during winding. Therefore, the exhaust gas purification device of the present invention can suppress the leakage of untreated exhaust gas from cracks in the gasket material (the sealing material).

[0180] Figure 7 This is a schematic cross-sectional view illustrating an example of the exhaust gas purification device of the present invention.

[0181] like Figure 7 As shown, the exhaust gas purification device 100 of the present invention includes: a housing 50; an exhaust gas treatment body 40 housed in the housing 50 and through which exhaust gas flows; and a retaining sealing material 60 disposed between the exhaust gas treatment body 40 and the housing 50 to retain the exhaust gas treatment body 40.

[0182] The sealing material 60 is a padding material wrapped around the outer periphery of the exhaust gas treatment body.

[0183] The exhaust gas treatment body 40 is a columnar treatment body with multiple channels 41 arranged side by side along its long side, separated by channel walls 42. One end of each channel is sealed with encapsulation material 43.

[0184] It should be noted that, as needed, the inlet pipe (for introducing exhaust gas from the internal combustion engine) and the outlet pipe (for discharging exhaust gas that has passed through the exhaust gas purification device to the outside) are connected to the end of the housing 50.

[0185] The following is for reference Figure 7 The case where the exhaust gas passes through the exhaust gas purification device 100 having the above-described configuration will be explained.

[0186] like Figure 7 As shown, the exhaust gas discharged from the internal combustion engine flows into the exhaust gas purification device 100. Figure 7 In the diagram, exhaust gas (represented by G, and its flow indicated by arrows) flows into a channel 41 of the exhaust gas treatment body (honeycomb filter) 40, which has an opening on the exhaust gas inflow side end face, and passes through the channel wall 42 that separates 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 then flows out through other channels 41 with openings on the exhaust gas outflow side end face and is discharged to the outside.

[0187] Figure 7In the exhaust gas purification device 100 shown, the sealing material 60 is the pad material 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 sheet (a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers) constituting the pad material of the present invention.

[0188] The material of 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. Specifically, stainless steel, aluminum, iron and other metals can be cited.

[0189] In addition to being roughly cylindrical, the shell shape can also be clam-shaped, roughly elliptical in cross-section, or roughly polygonal.

[0190] It should be noted that, Figure 7 The exhaust gas treatment body 40 shown is a filter in which any end of the channel 41 is sealed by the encapsulating material 43; however, in the exhaust gas treatment body constituting the exhaust gas purification device of the present invention, the ends of the channels may not be sealed. Such an exhaust gas treatment body can be suitably used as a catalyst carrier.

[0191] The exhaust gas treatment unit 40 can be made of non-oxide porous ceramics such as silicon carbide and silicon nitride, or it can be made of oxide porous ceramics such as alumina, cordierite, and mullite. Among these, silicon carbide is preferred.

[0192] The pore density in the cross-section of the exhaust gas treatment body 40 is not particularly limited, but the preferred lower limit is 31.0 pores / cm². 2 (200 pieces / inch) 2 The preferred upper limit is 93.0 pieces / cm². 2 (600 pieces / inch) 2 Furthermore, a more preferred lower limit is 38.8 particles / cm². 2 (250 pieces / inch) 2 The preferred upper limit is 77.5 particles / cm². 2 (500 pieces / inch) 2 ).

[0193] The waste gas treatment unit 40 can carry a catalyst for purifying the waste gas. The catalyst is preferably a precious metal such as platinum, palladium, or rhodium, with platinum being more preferred. Other catalysts may also be used, such as alkali metals like potassium and sodium, or alkaline earth metals like barium. These catalysts can be used individually or in combination.

[0194] If these catalysts are carried, they can be easily burned to remove PM and also purify toxic waste gases.

[0195] (Example)

[0196] The following provides further specific disclosure of embodiments of the present invention. It should be noted that the present invention is not limited to these embodiments.

[0197] (Example 1)

[0198] The basis weight (fiber weight per unit area) produced by the papermaking method is 2400 g / m². 2 Large-sized substrate pads made of inorganic fibers (mullite fibers).

[0199] As a large-size sheet, a laminated sheet (nonwoven fabric) is prepared by laminating longitudinally oriented PET fibers and transversely oriented PET fibers to form a fiber orientation in both the longitudinal and transverse directions. The PET fibers are oriented along their length, with the angle between the longitudinal and transverse orientations approximately 90°. Furthermore, the sheet has substantially square or rectangular openings. The sheet's basis weight (weighing) is 10 g / m². 2 .

[0200] The substrate pad and the sheet are heat-pressed together to obtain a... Figure 5 The attachment shown schematically is a rectangular attachment.

[0201] After that, regarding the attachment, and Figure 6 The configuration shown in the diagram is also punched to obtain two types of pad materials (the first pad material and the second pad material).

[0202] In the first padding material, the orientation direction of the longitudinally oriented fibers of the sheet is parallel to the long side direction of the padding material. In the second padding material, the orientation direction of the transversely oriented fibers of the sheet is parallel to the long side direction of the padding material.

[0203] (Comparative Example 1)

[0204] Large-sized substrate pads were fabricated in the same manner as in Example 1.

[0205] As a large-sized sheet component, a nonwoven fabric with randomly oriented PET fibers is prepared. The PET fibers are arranged longitudinally (MD) with a gentle orientation in this direction. Additionally, the sheet component has openings of random shapes such as parallelograms.

[0206] The substrate pad and the sheet are heat-pressed together to obtain a rectangular attachment with two longitudinal sides and two transverse sides.

[0207] Subsequently, the attachment was punched in the same manner as in Example 1 to obtain two types of pad materials (the first pad material and the second pad material).

[0208] In the first padding material, the long side of the PET fibers in the sheet is parallel to the length direction of the padding material. In the second padding material, the long side of the PET fibers in the sheet is parallel to the short side of the padding material.

[0209] Figure 8 This is an enlarged top view schematically showing the sheet of Comparative Example 1.

[0210] The sheet 30' of Comparative Example 1 has longitudinally oriented fibers 31 but no transversely oriented fibers. The opening 35 is formed by being surrounded by the longitudinally oriented fibers 31.

[0211] (Comparative Example 2)

[0212] Large-sized substrate pads were fabricated in the same manner as in Example 1.

[0213] As a large-sized sheet, it is prepared by laminating a longitudinal mesh (a longitudinal mesh with fiber orientation in the longitudinal direction by cutting fibers from a polyolefin film stretched in the longitudinal direction) and a transverse mesh (a transverse mesh with fiber orientation in the transverse direction by cutting fibers from a polyolefin film stretched in the transverse direction) and then thermally bonding them together. This sheet essentially has square or rectangular openings.

[0214] The substrate pad and the sheet are heat-pressed together to obtain a rectangular attachment with two longitudinal sides and two transverse sides.

[0215] Subsequently, the attachment was punched in the same manner as in Example 1 to obtain two types of pad materials (the first pad material and the second pad material).

[0216] In the first padding material, the orientation direction (longitudinal) of the longitudinal mesh of the sheet is parallel to the long side direction of the padding material. In the second padding material, the orientation direction (transverse) of the transverse mesh of the sheet is parallel to the long side direction of the padding material.

[0217] (Determination of average opening area and opening ratio)

[0218] Enlarged photographs of the sheets used in Example 1 and Comparative Example 2 were taken using a microscope.

[0219] Import the enlarged photograph into any graphic design software, draw rectangles that approximate the openings of the sheet, compare these rectangles with a reference rectangle whose area is known, and calculate the area of ​​the opening.

[0220] Then, the average of all calculated opening areas is taken as the average opening area of ​​the sheet (the average area of ​​each opening).

[0221] In addition, the percentage of the total calculated area of ​​all openings relative to the area occupied by the sheet in the enlarged photograph is used as the opening ratio.

[0222] The results are shown in Table 1.

[0223] (Twisting test)

[0224] The two types of padding materials (first padding material and second padding material) manufactured in each embodiment and comparative example are respectively wound onto... A cylindrical matrix.

[0225] During winding, the substrate pad is positioned on the base side, and the sheet is positioned on the outside.

[0226] The dimensions of the pad material along its long side (pad size) and the total length of the gap between the convex and concave parts at the point where the convex and concave parts meet (seam gap) are measured during the winding process.

[0227] For both types of padding materials, measure the total length mentioned above and calculate the difference (difference between padding material 1 and padding material 2).

[0228] The results are shown in Table 1.

[0229] In the differences, ○ indicates good and × indicates bad.

[0230] The smaller the difference between the first and second padding materials, the more uniform the padding material will be.

[0231] (Is there any crack in the padding material?)

[0232] For the two types of pads manufactured in each embodiment and comparative example, it was confirmed whether any cracks occurred after the above-mentioned winding test.

[0233] The results are shown in Table 1.

[0234] In the presence or absence of fracture, ○ indicates no fracture occurs, and × indicates fracture occurs.

[0235]

[0236] The results show that by using laminated sheets made by laminating longitudinally oriented fibers and transversely oriented fibers, the difference between the pad size of the first pad and the total length of the seam gap is reduced.

[0237] This means that two types of padding materials with similar winding properties are obtained, and that multiple pieces of well-winding padding materials can be obtained from a single large-sized attachment.

[0238] Furthermore, it can be seen that by making the average opening area of ​​the sheet greater than 0 mm² 2 / each and 0.7mm 2 / less than one can prevent the mat material from breaking during winding.

[0239] Figure 9 This is a photograph of the padding material in Comparative Example 2.

[0240] like Figure 9 As shown, in the padding material of Comparative Example 2, cracks occurred in the portion surrounded by the dotted line after the winding test.

[0241] Explanation of symbols

[0242] 1. First type of mattress material

[0243] 2. Second type of mattress material

[0244] 10. Mattressing Material

[0245] 11 convex part

[0246] 12 recess

[0247] 20, 120 base material pads

[0248] 21, 121 The first main surface of the substrate pad

[0249] 22 The second main surface of the substrate pad

[0250] 30 and 130 sheet

[0251] 31. Longitudinal oriented fibers

[0252] 32 transversely oriented fibers

[0253] 35 opening

[0254] 40 Waste Gas Treatment System

[0255] 41 channels

[0256] 42. Channel wall

[0257] 43 Packaging Materials

[0258] 50. Outer shell

[0259] 60. Maintain sealing material

[0260] 100 Exhaust Gas Purification Device

[0261] 150 Attached Spirits

Claims

1. A padding material having: Includes inorganic fibers, a substrate pad having a first primary surface and a second primary surface; and A sheet disposed on at least one of the first main surface and the second main surface, The characteristic of this padding material is that... The sheet is a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers. The sheet has openings surrounded by the longitudinally oriented fibers and the transversely oriented fibers. The average open area of ​​the sheet is greater than 0 mm. 2 / each and 0.7mm 2 / less than, The open area ratio of the sheet is greater than 0% and less than 40%.

2. The padding material as claimed in claim 1, wherein, The sheet is composed of at least one of organic and inorganic substances.

3. The padding material as described in claim 2, wherein, The sheet is composed of organic matter.

4. The padding material according to any one of claims 1 to 3, wherein, The sheet material is polyethylene terephthalate, polyethylene, or polypropylene.

5. The padding material according to any one of claims 1 to 3, wherein, The substrate pad further comprises at least one of an inorganic binder and an organic binder.

6. A waste gas purification device, comprising: Waste gas treatment system for circulating waste gas, The sealing material used to wrap around the outer periphery of the exhaust gas treatment body, and The outer casing of the exhaust gas treatment body, which is wrapped with the sealing material, is used to house the exhaust gas treatment body. The feature of this exhaust gas purification device is that... The sealing material is the gasket material according to any one of claims 1 to 5.

7. A method for manufacturing a padding material, comprising the following steps: The substrate preparation process involves preparing a substrate pad containing inorganic fibers and having a first main surface and a second main surface. Sheet preparation process, preparing the sheet, and In the sheet setting process, the sheet is set on at least one of the first main surface and the second main surface of the substrate pad. The manufacturing method is characterized by, The sheet is a laminated sheet formed by laminating longitudinally oriented fibers and transversely oriented fibers. The sheet has openings surrounded by the longitudinally oriented fibers and the transversely oriented fibers. The average open area of ​​the sheet is greater than 0 mm. 2 / each and 0.7mm 2 / less than, The open area ratio of the sheet is greater than 0% and less than 40%.

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