JP4712504B2 - Method of manufacturing cushion material for heat resistant press - Google Patents

Description

  The present invention relates to a method for producing a heat-resistant press cushioning material, and in particular, is arranged between a hot press machine and a molded product, prevents flaws in the hot press machine and a molded product, and transmits uniform pressure and heat, In addition, the present invention relates to a method for manufacturing a heat-resistant press cushion material having improved cushioning properties.

  Cushioning material for heat-resistant press is placed between the hot press machine and the molded product, and is used to prevent wrinkling of the hot press machine and apply uniform pressure and heat during press molding. , Durability is required. Conventionally, a stack of about 5 to 20 sheets of kraft paper has been used. However, since the number of times of use was about 1 to 5 times, it has hardly been used in recent years due to poor durability.

  On the other hand, as a cushioning material having improved durability, a material using synthetic rubber is provided and is still widely used. The typical structure is a combination of a woven fabric, non-woven fabric or felt layer made of heat-resistant fibers such as glass fiber and aromatic polyamide fiber, and a synthetic rubber layer such as butyl rubber or fluoro rubber, which are laminated and integrated. is there. Further, in order to give them release properties, it is known to bond and integrate a heat-resistant release layer such as a sheet coated with a fluororesin film or a heat-resistant resin on the surface of the cushion material.

In addition, a woven fabric made of heat-resistant fibers such as glass fiber, aromatic polyamide fiber, polyphenylene sulfide fiber, PBO fiber, etc. may be used on the surface, and these may be laminated and used. (Described in Patent Document 1) In this case, in addition to the cushioning property of the woven fabric on the surface, there is a feature that the cushioning property is further improved by the gap between layers generated when the layers are laminated.
Japanese Patent No. 3259741

  However, if felt that has been used in the past is used as a component of a cushioning material, the degree of freedom of the constituent fibers is large and soft. There is a problem that it is easy to generate a void and a problem that a lifetime is short.

  Further, the amount of bending required varies depending on the configuration of the molded product. In the case of a molded product that requires a large amount of deflection, there is a problem that the amount of deflection of the cushion material is insufficient.

  In addition, the rubber of the rubber layer is plasticized during vulcanization and flows into the voids of the woven or non-woven fabric layer, which reduces the cushion performance inherently possessed by the woven or non-woven fabric layer.

  SUMMARY OF THE INVENTION The present invention provides a method for manufacturing a cushion material for a heat-resistant press that improves the durability by improving the cushioning property, reducing the compression set and improving the durability. With the goal.

  That is, in the invention of the present application, in a method for producing a heat-resistant press cushion material used between a hot press machine and a molded product, a heat-resistant fiber member is used as a surface layer, and at least one bulky multi-layer is used as an intermediate layer. A woven cloth is arranged, and a laminate is produced in which an unvulcanized rubber layer is interposed between the surface layer and the intermediate layer and / or between the intermediate layers, and then the laminate is left under pressure without heating. The rubber layer is pressurized and vulcanized immediately after the start of the crosslinking reaction of the rubber layer, and is laminated and integrated. The rubber layer immediately after starting to crosslink under pressureless condition is pressurized and vulcanized. The heat-resistant press that can suppress the penetration of rubber into the multi-woven cloth, enhances cushioning, reduces compression set, and improves durability by ensuring sufficient space for air to exist. Cushion It can be produced.

  In the present invention, the laminate is left at a temperature of 150 ° C. to 180 ° C. in a non-pressure state for 0.2 to 15 minutes, and then pressurized and vulcanized in a state where this temperature is maintained. It is possible to reliably suppress rubber penetration into the multi-woven cloth during vulcanization.

  The present invention includes a case in which a heat-resistant fiber member is disposed on the surface layer, and a multi-layered woven cloth is disposed on the intermediate layer, and a rubber layer is interposed between the surface layer and the intermediate layer. Good durability, low compression set, and improved durability.

  The present invention includes a case where a heat-resistant fiber member is disposed on the surface layer, and two layers of multi-woven cloth are disposed on the intermediate layer, and a rubber layer is interposed between the surface layer and the intermediate layer, and the total thickness is Even if the amount of bending at the time of compressive deformation increases, the compression set can be reduced and the cushioning property can be maintained.

  Further, the present invention provides a configuration of a multi-woven cloth when the constituent yarn of the multi-woven cloth is a crimped yarn, the multi-woven cloth is a double-woven cloth, the multi-woven cloth is a quad-woven cloth, When the yarn is at least one inorganic fiber selected from glass fiber, carbon fiber, and ceramic fiber, the heat-resistant fiber member of the surface layer is selected from aromatic polyamide fiber, polyphenylene sulfide fiber, glass fiber, and carbon fiber When the heat resistant fiber member of the surface layer is composed of aromatic polyamide fiber spun yarn, the heat resistant fiber member of the surface layer is treated with a heat resistant resin. And a case where a rubber layer reinforced with short fibers is interposed between the surface layer and the intermediate layer.

  In the method for producing a heat-resistant press cushion material of the present invention, the rubber layer immediately after starting to crosslink by leaving the laminate in a non-pressurized state is pressurized and vulcanized, and laminated and integrated, Rubber penetration into the multi-woven cloth can be suppressed, the cushioning property can be improved by sufficiently securing a space in which air is contained, and at least one bulky multi-woven cloth is used as a constituent member. Therefore, it has a function to prevent the deformation of the cushion material when the space portion is provided and the cushioning property and the press are repeated, and it is possible to reduce the compressive strain and improve the durability.

  The present embodiment will be described below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a heat-resistant press cushion material obtained by the method of the present invention. A heat-resistant press cushion material 1 according to the present invention includes a surface layer 3 composed of a heat-resistant fiber member 2, a bulky material. The intermediate layer 6 made of a certain multi-woven cloth 5, and the surface layer 3 and the intermediate layer 6 are vulcanized and integrated with the surface layer 3 and the rubber layer 7 partly impregnated in the intermediate layer 6 between each layer. It is a bonded laminate. Since the intermediate layer 6 uses bulky fibers and is a multi-woven cloth, there are many space portions and has a function of preventing cushioning and deformation of the cushioning material when the press is repeated. .

  In addition, the heat-resistant press cushion material 1 shown in FIG. 2 has two intermediate layers 6 made of a bulky multi-woven cloth 5 laminated. That is, the cushion material 1 includes a surface layer 3 made of a heat resistant fiber member 2, an intermediate layer 6 made of a bulky multi-woven cloth 5, and between the surface layer 3 and the intermediate layer 6, and an intermediate layer 6. A rubber layer 7 is interposed between the intermediate layer 6 and the intermediate layer 6 and between the intermediate layer 6 and the surface layer 3, and is a vulcanized and integrated laminate. The heat-resistant press cushioning material 1 maintains the cushioning effect even when the amount of deflection is increased because the compressibility does not change even when the total thickness is increased as compared with the case where the single intermediate layer 6 is used. be able to.

  In the present invention, about 3 to 5 intermediate layers 6 made of multiple woven cloth 5 can be laminated.

  In the production method of the present invention, rubber layers 7, which are unvulcanized rubber sheets having a thickness of 0.10 to 0.50 mm, are laminated on both surfaces of the multi-woven cloth 5, and heat resistance is further applied to each surface of the rubber layer 7. The functional fiber cloth 2 is laminated, and the laminate is left in a normal press vulcanizer at a temperature of 150 to 180 ° C. for 0.2 to 15 minutes and under no pressure. Immediately after the rubber layer 7 starts to be crosslinked, the surface pressure is increased to 0.1 to 5.0 MPa while maintaining the above temperature, vulcanized in 10 to 40 minutes, laminated and integrated, and the heat resistance shown in FIG. The cushioning material 1 for a press is produced.

 In the manufacturing method of the heat-resistant press cushion material 1 shown in FIG. 2, rubber layers 7, which are unvulcanized rubber sheets having a thickness of 0.10 to 0.50 mm, are laminated on both surfaces of the multi-woven cloth 5. Further, after laminating multiple woven cloth 5, a similar rubber layer 7 is laminated on one side to form two intermediate layers 6, and heat-resistant fiber cloth 2 is laminated on both sides. The rubber layer 7 is allowed to stand in a non-pressure state at a temperature of 150 ° C. to 180 ° C. for 0.2 to 15 minutes to start the crosslinking reaction of the rubber layer 7. At the same temperature, the surface pressure is increased to 0.1 to 5.0 MPa, these are vulcanized in 10 to 40 minutes, and laminated and integrated. In this way, the rubber layer is preliminarily subjected to a crosslinking reaction without pressure, and the surface layer and the intermediate layer are laminated and integrated, so that the rubber penetration into the multi-woven cloth can be suppressed during vulcanization, Cushioning property can be enhanced by sufficiently securing the internal space.

  The time for which the pressure is left without pressure is preferably longer than the time at the minimum torque value of the rheometer test and less than the time at the maximum torque value. In the case of the present invention, 0.2 to 15 minutes is preferable. In the case of less than the time at the minimum torque value, when the laminate is pressurized and vulcanized, the rubber layer flows into the multi-woven cloth 5 and fills the gaps between the fibers. Durability cannot be obtained. On the other hand, when the time is equal to or more than the time at the maximum torque value, the adhesion between the rubber layer and the multi-woven cloth becomes poor, and the surface layer and the intermediate layer are easily separated.

  Further, in order to further improve the compressive strain resistance, after-curing may be performed at 200 to 250 ° C. for 30 minutes to 4 hours.

  The bulky multi-woven cloth 5 includes a double woven cloth, a triple woven cloth, a quadruple woven cloth, etc., which are made of bulky processed yarns or bulky processed in a cloth state. Also good.

  For example, as shown in FIG. 1, in the double weave cloth, the weft 8a is entangled with the fourth warp 9 on the front surface and the other weft 8b at the same position on the back surface is similarly entangled with the fourth warp 9 as shown in FIG. It has a heavy weave structure. Thus, since the double woven cloth has many gap portions, it has a function of preventing cushioning and deformation of the cushion material when the press is repeated. Since the use environment at the time of press molding is 200 ° C. or more and requires a use time of about 80 minutes, the cushion material cannot be reinforced and deformed without heat resistance. Moreover, if there is no space between the filaments, high cushioning properties are not exhibited. Therefore, it is heat-resistant, high-strength, high-elasticity fiber, and additionally crimped.

  Further, for example, as shown in the schematic diagram of FIG. 3, the triple woven cloth has warps 9a, 9b, 9c, 9d, 9e, 9f, 9g and the like arranged in parallel, and the outermost weft 8A is composed of warps 9b and 4 The middle weft 9B is entangled with the middle weft 8B and the second warp 9e, and the innermost weft 8C is entangled with the warp 9d. The triple woven cloth has a structure in which three wefts 8A, 8B and 8C are laminated.

  Further, for example, as shown schematically in FIG. 4, the quadruple woven cloth has warps 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, etc. arranged in parallel, and the outermost weft 8A is The second layer weft 8B is entangled with the warp 9b and the sixth 9h, the third layer weft 8C is entangled with the warp 9d and the second 9f, and the innermost weft 8D has a configuration involving the warp 9e. The four-woven cloth has a structure in which four wefts 8A, 8B, 8C, 8D are laminated.

  The constituent yarn of the multi-woven cloth 5 is a fiber having high strength, high elasticity, and heat resistance such as aramid fiber, PBO (polybenzobisoxazole) fiber, glass fiber, carbon fiber, ceramic fiber, etc., preferably glass Examples include inorganic fibers such as fibers, carbon fibers, and ceramic fibers.

  The heat-resistant fiber member 2 forming the surface layer 3 has a use environment of 200 ° C. or higher during press molding and requires a use time of about 80 minutes. In close contact.

  As the heat resistant fiber member 2, aramid fiber, PBO fiber, fluorine fiber, glass fiber, carbon fiber, ceramic fiber and the like are used, and cloth, non-woven fabric, knitted fabric, felt and the like can be used.

  In some cases, the heat-resistant fiber member 2 may be impregnated with a heat-resistant resin. Examples of the heat-resistant resin include an epoxy resin, a phenol resin, a melanin resin, a fluorine resin, an unsaturated polyester resin, a silicone resin, a polyimide resin, a thermosetting acrylic resin, a furan resin, a urea resin, and a diallyl phthalate resin. Blend systems or copolymers may be mentioned.

  As the rubber layer 7, the cushioning property of the cushion material is expressed. The required properties are heat resistance and low compressive strain, the thickness is 0.05 to 1.00 mm, and the rubber hardness (JIS A) is 65 to 85 ° is preferable. Examples of the rubber used as the rubber layer 7 include fluorine rubber and silicon rubber. Fluoro rubbers include fluorine-containing acrylate polymers, vinylidene fluoride copolymers, fluorine-containing silicon rubbers, and fluorine-containing polyester rubbers as raw materials.

  This fluoro rubber and silicon rubber have diacyl peroxide, peroxy ester, diallyl peroxide, di-t-butyl peroxide, t-butyl cumyl peroxide, dicumyl peroxide, and 2,5-dimethyl as vulcanizing agents. -2,5-di (t-butylperoxy) -hexane-3, 1,3-bis (t-butylperoxy-isopropyl) benzene, 1,1-di-butylperoxy-3, 3, 5- Organic peroxide-based vulcanizing agents such as trimethylcyclohexane, polyol-based vulcanizing agents such as hexamethylene carbamate, N, N′-dicyanyldiene-1,6-hexadiamine, bisphenol AF, benzyltriphenylphosphonium chloride, and Triethylenetetramine (TETA), triethylenepentamine (TEPA), Such hexamethylenediamine (HMDA) amine-based vulcanizing agent such as, can be a known as a vulcanizing agent of the fluorine rubber. The addition amount is about 0.2 to 5.0 parts by mass, preferably 0.5 to 3.0 parts by mass, with respect to 100 parts by mass of the polymer.

  In addition to these, those used for usual rubber compounds such as fillers, plasticizers, stabilizers, processing aids, and colorants are contained as necessary. Moreover, you may fill 5-30 mass parts of short fibers of length 1-10 mm with respect to 100 mass parts of rubber | gum for rubber reinforcement. As the short fibers, for example, aramid fibers such as trade names Conex, Nomex, Kevlar, Technora and Twaron, heat resistant fibers such as PBO fibers and glass fibers are used.

Example 1
The heat-resistant fiber cloth of the surface layer is Cornex fabric (CO1910 manufactured by Teijin Ltd.), the intermediate layer is a double woven cloth made of crimped glass fiber (KS4325 manufactured by Nittobo), and the polyol is polyol. A vulcanized fluororubber (DuPont Viton V9006) was prepared.

  A structure in which two intermediate layers are laminated, fluororubber is formed into a sheet having a thickness of 0.30 mm by a calender roll, laminated between the intermediate layers and between the intermediate layer and the surface layer, and is initially heated for 5 minutes at a temperature of 165 ° C. , Held in a non-pressure state, partially cross-linked fluororubber, then set the surface pressure to 2.0 MPa, vulcanized at a temperature of 165 ° C. for 15 minutes, and laminated and integrated to produce a cushioning material did. The total thickness of the cushion material was 3.15 mm.

  The amount of bending of the obtained cushion material when the surface pressure was 1 MPa and the surface pressure was 5 MPa was measured. As a result, they were 0.55 mm and 0.95 mm, respectively.

  Further, the obtained cushioning material was brought into a state of a surface pressure of 5 MPa, heated from 50 ° C. to 200 ° C. over 30 minutes, held at 200 ° C. for 15 minutes, then cooled to 50 ° C. over 30 minutes, Pressure is applied. As a result of repeating this pattern 200 times, the amount of deflection at a surface pressure of 1 MPa and a surface pressure of 5 MPa was 0.45 mm and 0.60 mm, respectively.

Example 2
A cushioning material was produced in the same manner as in Example 1 except that the intermediate layer was a four-layer woven cloth and one sheet was laminated. The thickness of the cushion material was 3.12 mm. The amount of deflection of the obtained cushion material when the surface pressure was 1 MPa and the surface pressure was 5 MPa was 0.95 mm and 1.20 mm, respectively.

  Further, the obtained cushioning material was brought into a state of a surface pressure of 5 MPa, heated from 50 ° C. to 200 ° C. over 30 minutes, held at 200 ° C. for 15 minutes, then cooled to 50 ° C. over 30 minutes, Pressure is applied. As a result of repeating this pattern 200 times, the amount of deflection at a surface pressure of 1 MPa and a surface pressure of 5 MPa was 0.55 mm and 0.65 mm, respectively.

Comparative Example 1
A material and a laminated structure similar to those in Example 1 were formed, and the pressure was adjusted to 2.0 MPa with a press, and these were vulcanized and integrated at a temperature of 165 ° C. for 15 minutes to produce a cushion material. The total thickness of the cushion material was 2.28 mm. The amount of deflection of the obtained cushion material when the surface pressure was 1 MPa and the surface pressure was 5 MPa was 0.05 mm and 0.15 mm, respectively.

Comparative Example 2
The laminated structure is the same as that of Example 2 except that a quadruple woven cloth made of non-crimped glass fibers is used instead of the quadruple woven cloth made of crimped glass fibers in the intermediate layer. Then, the surface pressure was set to 2.0 MPa, and these were vulcanized and integrated at a temperature of 165 ° C. for 15 minutes to prepare a cushion material. The thickness of the cushion material was 2.45 mm. The amount of deflection of the obtained cushion material when the surface pressure was 1 MPa and the surface pressure was 5 MPa was 0.21 mm and 0.35 mm, respectively.

Comparative Example 3
A cushioning material was prepared in the same manner as in Comparative Example 2 except that a felt made of a meta-aramid fiber was used instead of the quadruple woven cloth made of glass fiber in the intermediate layer. The thickness of the buffer material was 2.10 mm. The amount of deflection of the obtained cushion material when the surface pressure was 1 MPa and the surface pressure was 5 MPa was 0.23 mm and 0.43 mm, respectively.

  The cushioning material for heat-resistant presses according to the present invention is provided between the hot press machine and the molded product to prevent wrinkling of the hot press machine during pressure molding and to give uniform pressure and heat. is there.

It is sectional drawing of the cushion material for heat resistant presses obtained by the method of this invention. It is sectional drawing of the cushion material for heat resistant presses which is another Example obtained by the method of this invention. It is the schematic of a triple woven cloth. It is the schematic of a quadruple woven cloth.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cushion material for heat resistant presses 2 Heat resistant fiber member 3 Surface layer 5 Multi-woven cloth 6 Intermediate layer 7 Rubber layer 8 Weft 9 Warp

Claims (12)

  In the method of manufacturing a heat-resistant press cushioning material used between a hot press machine and a molded product, a heat-resistant fiber member is disposed on the surface layer, and at least one bulky multi-woven cloth is disposed on the intermediate layer, After producing a laminate including an unvulcanized rubber layer between the surface layer and the intermediate layer and / or between the intermediate layers, the laminate is allowed to stand in a non-pressure state under heating to cause a crosslinking reaction of the rubber layer. Immediately after starting to start pressurizing, vulcanizing, and laminating and integrating, a method for producing a heat-resistant press cushioning material.   The heat resistant press according to claim 1, wherein the laminate is allowed to stand for 0.2 to 15 minutes at a temperature of 150 ° C to 180 ° C in a non-pressurized state, and then pressurized and vulcanized while maintaining the temperature to integrate the laminate. Method for manufacturing cushion material.   The heat resistant press member according to claim 1 or 2, wherein a heat resistant fiber member is disposed on the surface layer, and one multi-woven cloth is disposed on the intermediate layer, and a rubber layer is interposed between the surface layer and the intermediate layer. Cushion material manufacturing method.   The heat resistant press member according to claim 1 or 2, wherein a heat resistant fiber member is disposed on the surface layer and two layers of multi-woven cloth are disposed on the intermediate layer, and a rubber layer is interposed between the surface layer and the intermediate layer. Cushion material manufacturing method.   The method for manufacturing a heat-resistant press cushion material according to any one of claims 1 to 4, wherein the constituent yarn of the multi-woven cloth is a crimped yarn.   The method for producing a heat-resistant press cushion material according to any one of claims 1 to 5, wherein the multi-woven cloth is a double-woven cloth.   The method for producing a heat-resistant press cushion material according to any one of claims 1 to 5, wherein the multi-woven cloth is a four-woven cloth.   The method for producing a heat resistant press cushion material according to any one of claims 1 to 7, wherein the constituent yarn of the multi-woven cloth is at least one inorganic fiber selected from glass fiber, carbon fiber, and ceramic fiber.   The heat-resistant fiber member of the surface layer is composed of at least one heat-resistant fiber selected from aromatic polyamide fiber, polyphenylene sulfide fiber, glass fiber, and carbon fiber. Manufacturing method of cushion material for heat resistant press.   The method for producing a heat-resistant press cushion material according to any one of claims 1 to 8, wherein the heat-resistant fiber member of the surface layer is composed of a spun yarn of an aromatic polyamide fiber.   The manufacturing method of the cushion material for heat resistant presses in any one of Claims 1 thru | or 10 with which the heat resistant fiber member of the surface layer was processed with the heat resistant resin. The method for producing a heat-resistant press cushion material according to any one of claims 1 to 11, wherein a rubber layer reinforced with short fibers is interposed between the surface layer and the intermediate layer.

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