JP2003117935A - Method for producing cushioning material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently mass-produce a cushioning material without scattering in performance and thickness. SOLUTION: In a method for producing the cushioning material to be used in hot pressing, a process for obtaining a sheet-like material by installing a heat resistant rubber layer on one side surface or both surfaces of a heat resistant cloth of long size, and a process for continuously pressurizing and vulcanizing an article in which two or more sheet-like materials 13 are stuck to each other while they are carried between a hot drum 5 and a belt 9 are provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing a cushion material used for hot press molding.

[0002]

2. Description of the Related Art As is well known, a method of forming a printed circuit board, a multi-layer laminate, a liquid crystal display panel, etc. by laminating these constituent materials, sandwiching them between hot plates, and heating under pressure is used. There is. Generally, in such hot press molding, in order to apply uniform heat and pressure over the entire surface of the molded product, a method of interposing a cussion material between the hot platen and the molded product is adopted. There is. FIG. 1 is an example thereof, in which a hot platen 1, a cushion material 2, and a press plate 3 are formed into a molded product 4 from above and below, respectively.
Sandwich it and apply heat and pressure to mold it.

The cushion material 2 used in these hot press moldings has a structure in which heat-resistant rubber, woven or non-woven fabric made of heat-resistant fiber, synthetic resin, paper, metal plate, etc. are appropriately laminated and integrated. Is used. Above all, the cushioning material mainly composed of a rubber layer and a fiber layer has a performance having both elasticity of rubber and compressibility of fibers, and is used in a wide range of fields.

Generally, rubber is rich in elasticity, but in a cushion material made of only rubber, the deformation amount of the rubber due to pressing is different between the central portion and the end portion of the cushion material.
The transmission of force varied and uniform pressing was not possible, and the strength was insufficient. Therefore, a cushioning material is used in which a fiber layer is laminated together with a rubber layer to give the compressibility of the fiber layer and the strength of the fiber.

Generally, a method for manufacturing a cushion material is as follows:
For example, the following is used. Pressing method: A pressing method in which a sheet-like material obtained by laminating an unvulcanized rubber sheet and a fiber layer is sandwiched between two iron plates, and heat and pressure are applied to vulcanize the rubber to integrate it. The vulcanization conditions in this case are vulcanization temperature 150 to 200 ° C. and vulcanization time 5 to 120.
The press pressure is generally 1 to 3 MPa.

Can vulcanization method: The sheet material is wound around a metal drum for several turns, put in a vulcanization can, and then heated to 150-
A method of vulcanizing and integrating rubber at 170 ° C for 1 to 6 hours at an air pressure of about 0.5 MPa. Oven method: A method in which the sheet material is placed in a hot-air oven and the rubber is vulcanized and integrated under the same conditions as the can vulcanization method.

[0007]

However, the conventional method has the following problems. Press method: Since only one press vulcanization can be performed up to the size of the press plate, the product size is limited and the efficiency is poor.

Can vulcanization method: Since pressing pressure cannot be applied to the sheet-like material, defective adhesion between the rubber sheet and the fiber is likely to occur. Generally, air is fed and air pressure is applied for vulcanization, but since air pressure is applied to all surfaces of rubber and fibers, no effect can be expected on the adhesion between the rubber sheet and the fibers. Further, since it is difficult to increase the air pressure as compared with the pressing pressure, air residue may occur in the rubber. Although it is possible to apply pressure to the sheet-shaped material by winding it while winding the sheet-shaped material or after winding it, it is difficult to apply pressure evenly over the entire surface of the sheet-shaped material. There are variations in performance and thickness.

Oven system: The same as the above-mentioned can vulcanization system, and only the size in the oven can be molded.

The present invention has been made in consideration of these circumstances. After a heat-resistant rubber layer is provided on one or both sides of a long heat-resistant woven fabric to obtain a sheet-like product, the sheet-like product is obtained. A method for manufacturing a cushioning material that can be efficiently mass-produced without unevenness in its performance and thickness by continuously vulcanizing one or more adhered ones while being conveyed between a thermal drum and a belt. provide.

[0011]

The present invention relates to a method for producing a cushioning material used for hot press molding, in which a sheet-shaped article is obtained by providing a heat-resistant rubber layer on one or both sides of a long heat-resistant woven fabric. And a step of continuously press-vulcanizing the sheet-shaped material or a material obtained by laminating two or more sheet-shaped materials together between a heating drum and a belt. It is a manufacturing method of a cushion material.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The method for manufacturing the cushion material of the present invention will be described in more detail below. In the present invention, the prepared rubber compound is passed between two rolls to be molded into a sheet, but the rubber compound may be extruded into a sheet with an extruder and further thinned with a calendar. By using the rubber sheet thus obtained, a cushioning material having excellent thickness accuracy can be manufactured.

Then, the sheet-shaped rubber is superposed on the long woven cloth. By stacking the sheet-shaped rubber on the woven cloth, the use of the solvent is avoided and the working environment is improved as compared with the case where the rubber compound in which the rubber compound is mixed with the solvent is applied on the woven cloth. Further, in the case of gluing, the gluing work has to be repeated until the desired thickness is reached, but the labor is eliminated and the work efficiency is improved. Conversely, if a thin rubber layer is desired, rubber glue can be used to form the rubber layer.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The method for manufacturing the cushion material of the present invention will be described in more detail below. The rubber layer used in the present invention is made of heat resistant rubber because it is used at 120 ° C. or higher during hot pressing. As the material of heat resistant rubber,
For example, H-NBR, fluororubber, silicone rubber, E
PDM may be mentioned, but preferably a binary polyol vulcanized fluororubber excellent in compression set is used.
Here, it is optional to add a vulcanizing agent, a filler, and other various compounding agents to the rubber used, if necessary.

The heat resistant woven fabric used in the present invention includes:
For example, aromatic polyamide fiber, aromatic polyester fiber, carbon fiber, phenol resin fiber, fluororesin fiber,
PBO (Boriparaphenylene benzobisoxazole)
It is a long woven fabric made of fibers, glass fibers, alumina fibers, metal fibers and the like.

According to the present invention, a long rubber sheet and a woven cloth are bonded together to form a sheet, and the cushion material can be efficiently manufactured by continuously press-vulcanizing the sheet.

Although a non-woven fabric may be used as the cushion material, it is difficult to form a long sheet-like product, especially when a thin or low-density non-woven fabric is used. It is difficult to vulcanize continuously. In addition, since the woven cloth is superior in thickness accuracy, variations in the thickness of the cushion material can be suppressed, and the woven cloth has an advantage that it does not stretch more than necessary than the non-woven cloth.

In the present invention, first, a sheet-shaped article is formed by laminating a sheet-shaped heat-resistant rubber layer on one side or both sides of a long woven fabric. Depending on the structure of the cushion material, a plurality of the sheet-like materials may be overlapped to form a sheet-like material having a plurality of rubber sheets and a woven cloth.

A sheet-like material obtained by laminating a rubber sheet and a woven fabric is passed, for example, between a heating drum and a belt wound around a part of the peripheral surface of the heating drum, and the heat of the heating drum and
Due to the rotation of the heating drum and the accompanying movement of the belt, it is continuously vulcanized while being pressurized. Here, as a vulcanizer capable of continuously vulcanizing a long sheet-like material,
For example, a roto cure and an Aumar vulcanizer are mentioned.

These vulcanizers are constructed as shown in FIG. Reference numeral 5 in the drawing denotes a heating drum having a cylindrical shape made of metal and having a structure in which steam is circulated in the inner cavity. A drive roll 6 is arranged near the upper part of the thermal drum 5, a guide roll 7 is arranged near the rear part, and a guide roll 8 is arranged near the lower part. An endless belt 9 made of metal is wound around a part of the peripheral surfaces of the thermal drum 5 and the rolls 6 to 8. In addition,
The endless belt 9 may have a structure in which a metal mesh is coated with heat resistant rubber. When the drive roll 7 is rotationally driven, the endless belt 9 runs and the thermal drum 5 and the guide rolls 7 and 8 rotate.

The sheet material 10 is inserted between the thermal drum 5 and the endless belt 9 and is conveyed together with the endless belt 9 in the direction of arrow c, and the heat of the thermal drum 5, the thermal drum 5 and the endless belt 9 are conveyed. The sheet-like material 10 is continuously pressure-vulcanized by the pressure in between. At this time, by moving the guide roll 8 in the vertical direction (arrow b), the sheet-shaped material 1
Adjust the insertion angle of 0.

In the present invention, the vulcanization conditions are temperature 120-
180 ° C., pressure 1-20 MPa, preferably 6-12 MP
It can be arbitrarily selected in the range up to a. Vulcanization time is 1-6
It is 0 minutes (the time at which an arbitrary point of the sheet-like material is in contact with the heating drum, the same applies to the following examples), and can be arbitrarily adjusted according to the above conditions. Further, during continuous vulcanization, the tension applied to the endless belt 9 is adjusted by moving the guide roll 7 in the left-right direction (arrow a), and the sheet-shaped material 10 is interposed between the thermal drum 5 and the endless belt 9. The pressure on the can be adjusted. When the pressure is increased, a large amount of rubber enters the mesh of the woven cloth, the compressibility of the cushion material is limited, and a harder cushion material can be manufactured. On the other hand, when the pressure is weakened, the amount of rubber that enters the mesh of the woven cloth decreases, and the compressibility of the cushioning material increases. In the present invention, the compressibility of the cushion material can be easily adjusted by changing the pressure between the drum and the belt.

In the present invention, when the surface of the cushion material is rubber, there is a problem that the cushion material and the hot platen or intermediate plate (press plate) in contact with the cushion material adhere to each other when the press is released. Alternatively, a woven fabric layer or a resin film may be provided to impart releasability.
A non-woven fabric is not preferable as a surface layer because its structure lacks thickness accuracy and there is a risk of fibers falling off and it is inappropriate to use it on the surface of a cushion material. When a surface layer of woven fabric or resin film is provided, one side of the woven fabric laminated with a rubber sheet at the time of molding the sheet-like material may be used as the surface of the cushion material, or the surface of the sheet-like material may be newly woven. After providing the cloth layer and the resin film layer, they are pressure-vulcanized by a continuous vulcanizer to be integrated.

In the case where a cushioning material having a higher thickness accuracy is desired, the rubber layer surface is polished after pressure vulcanization of the sheet-like material, and then the surface layer is provided on the surface with an adhesive. May be. By providing the surface layer on the polished rubber surface, the accuracy of the thickness of the cushion material is increased, and the variation in compressibility at the time of pressing can be suppressed. Specifically, after pressure-vulcanizing a sheet-shaped article obtained by laminating an unvulcanized heat-resistant rubber layer and a heat-resistant woven fabric layer of an intermediate layer provided between the rubber layers,
The surface of the rubber layer is polished. At this time, Ra is less than 10 μm, preferably less than 5 μm, and Rz is less than 50 μm, preferably 20.
It is desirable to polish to less than μm. As the surface woven fabric layer, a woven fabric made of the above-mentioned heat resistant fiber can be similarly used, and as the resin film, for example, a fluororesin film, a polyimide film, a polyester film, a triacetate film, a TPX film, a polyolefin film can be used. Can be used.

In the present invention, if necessary, post-vulcanization may be performed at 160 to 240 ° C. for 30 minutes to 8 hours after the continuous vulcanization. By performing the post-vulcanization, the progress of the vulcanization is completed and the intermolecular bond of the rubber is strengthened. Further, as described above, when the surface layer is provided after the continuous pressure vulcanization, it is necessary to cure the adhesive. Therefore, heat is applied under the above conditions for both curing and post vulcanization of the adhesive.

[0026]

EXAMPLES A method of manufacturing a cushion material according to the present invention will be described below. (Example 1) First, as a raw material rubber, fluororubber (trade name: Florel FC-2176, manufactured by Sumitomo 3M Ltd.)
Then, a vulcanizing agent, a vulcanization accelerator, a filler and the like were kneaded to prepare a rubber compound. Next, the rubber compound was passed between two metal rolls to obtain a rubber sheet 12a.

Next, the rubber sheet 12a is topped on one side of a long woven fabric (1200 mm × 50 m) 11 made of aromatic polyamide fiber (trade name: Conex, manufactured by Teijin Ltd.) Two sets of sheet-like materials 13 each having a rubber layer 12b formed thereon were prepared by applying a rubber paste prepared by dissolving a rubber compound in a solvent on the other surface. Next, these sheet-like materials 13 are laminated so that the rubber layers 12b are adjacent to each other, and 10M is obtained using an Aumar vulcanizer.
Pressure vulcanization was continuously carried out at 160 ° C. for 20 minutes at Pa. Further, after cooling, both surfaces thereof were polished with a grindstone and cut into product dimensions to obtain a cushion material 14 having rubber layers on both surfaces.

According to the first embodiment, the sheet-shaped article 1 is obtained by providing the heat-resistant rubber layers 12a and 12b on both surfaces of the long woven cloth 11.
3 is formed, then two sets of the sheet-like materials 13 are bonded and continuously pressurized and vulcanized while being conveyed between the thermal drum 5 and the endless belt 9 under predetermined conditions. There is no variation in thickness and efficient mass production is possible.

Example 2 First, in the same manner as in Example 1, two sets of sheet-like materials were prepared and these sheet-like materials were bonded together. Next, two sets of sheet-like materials each having a rubber layer formed on only one side of a woven cloth with rubber glue were prepared, and the respective rubber surfaces were bonded to both sides of the previously prepared sheet-like material. Subsequently, this was continuously pressure-vulcanized at 13 MPa and 170 ° C. for 30 minutes, and then cut into product dimensions to obtain a cushion material having woven fabric layers on both sides.

The second embodiment has the same effect as the first embodiment.

(Example 3) First, the same rubber compound as in Example 1 was extruded into a sheet using an extruder and passed through a calendar to obtain a rubber sheet having a thickness of 0.5 mm. Next, two sets of sheet-like materials obtained by topping both sides of the rubber sheet on the same long woven fabric as in Example 1 were prepared, and these sheet-like materials were bonded together. Subsequently, the surface of a sheet of polytetrafluoroethylene (trade name: Teflon, manufactured by DuPont) as a fluororesin film was etched, and then the sheet was pasted with an adhesive through an Aumar vulcanizer. Was continuously pressure-vulcanized at 170 ° C. for 30 minutes at 15 MPa. Further, after cooling, one side of the rubber surface was polished with a grindstone and cut into product dimensions to obtain a cushion material having a film on one side.

The third embodiment has the same effect as the first embodiment.

Example 4 First, as in Example 1, the sheet-like material was continuously pressure-vulcanized, cooled, and then both surfaces thereof were polished. The surface roughness at this time is Ra2 μm, Rz10 μ
It was m. Next, the rubber compound obtained by dissolving the rubber compound obtained in Example 1 in a solvent was applied as an adhesive to the woven fabric made of Conex, and after being bonded to the sheet-like material, the adhesive was cured and post-treated. It was also heated in an oven at 200 ° C. for 2 hours for vulcanization. After that, cut into product dimensions,
A cushion material having woven fabric layers on both sides was obtained.

The fourth embodiment has the same effect as the first embodiment.

Example 5 First, as in Example 1, the sheet-like material was continuously pressure-vulcanized, cooled, and then both surfaces thereof were polished. The surface roughness at this time is Ra2 μm, Rz10.
was μm. Next, on the surface, as an adhesive, a ketanol-based solvent dissolved in a solvent (trade name, manufactured by Hitachi Chemical Co., Ltd.) was applied, and after the woven fabric made of Conex was pasted, the adhesive was cured and then 2 at 220 ° C for vulcanization
It was heated in an oven for an hour, and then cut into product dimensions to obtain a cushion material having woven fabric layers on both sides.

The fifth embodiment has the same effects as the first embodiment.

[0037]

As described above in detail, according to the present invention, a heat-resistant rubber layer is provided on one or both sides of a long heat-resistant woven fabric to obtain a sheet, and then the sheet is It is possible to provide a method for producing a cushioning material which can be efficiently mass-produced without variations in performance and thickness by continuously pressurizing and vulcanizing one or more bonded ones while being conveyed between a heating drum and a belt.

[Brief description of drawings]

FIG. 1 is an explanatory view of a method of molding with a cushion material interposed between a hot platen and a molded product.

FIG. 2 is an explanatory view of a method for manufacturing a cushion material according to the present invention.

FIG. 3 is an explanatory view of a cushion material according to the present invention.

[Explanation of symbols]

5 ... Heat drum, 6 ... drive roll, 7, 8 ... Guide roll, 9 ... endless belt, 10 ... Sheet-like material, 11 ... Woven cloth, 12a, 12b ... rubber sheet, 13 ... Sheet-like material, 14 ... Cushion material.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshikazu Shimizu             1-32 Osaki, Shinagawa-ku, Tokyo Stock market             Company Kimyang (72) Inventor Hiroo Miwano             1-32 Osaki, Shinagawa-ku, Tokyo Stock market             Company Kimyang F-term (reference) 4F204 AA45 AB03 AD05 AD16 AG03                       AH33 AH36 FA06 FB02 FB11                       FB13 FB22 FF01 FF05 FN11                       FN15 FN17 FW24 FW33 FW43

Claims (3)

[Claims] 1. A method for producing a cushioning material used for hot press molding, comprising the steps of providing a heat-resistant rubber layer on one or both sides of a long heat-resistant woven fabric to obtain a sheet-like product, and the sheet-like product. A method for producing a cushioning material, which comprises a step of continuously vulcanizing an article or two or more sheet-like articles thereof bonded together while being conveyed between a heating drum and a belt. 2. The cushioning material according to claim 1, wherein after heat-vulcanizing the sheet-like material, the heat-resistant rubber layer is polished, and a surface layer is formed on the surface of the heat-resistant rubber layer via an adhesive. Manufacturing method. 3. 160 to 2 after pressure vulcanization of a sheet material
The post-vulcanization is performed under the conditions of 40 ° C. and 30 minutes to 8 hours, and the method for producing a cushioning material according to claim 1.