JPH07121994B2 - Manufacturing method of cork vents - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a cork vent having excellent mechanical properties.

[0002]

2. Description of the Related Art Cork products, such as sheets and plates, have been obtained by slicing or crushing natural cork materials, using natural rubber or synthetic resin as a binder, and joining and compressing them to obtain a product having a required shape.

[0003]

The product obtained by the above-mentioned production method has a natural appearance unique to cork, a soft texture, etc., but has low mechanical strength and poor breathability. Despite being desired to be used for shoes insoles / insoles, sheets applied to the back of various devices and instruments, etc., it has poor durability, and it accumulates heat when used for a long time, sags, etc. Could not be popularized for. An object of the present invention is to produce a cork-made ventilation body that can solve such problems.

[0004]

SUMMARY OF THE INVENTION The present invention is based on the following two manufacturing methods. (A): 50 to 100 parts by weight of polyamide fiber is kneaded with 100 parts by weight of polymer. (B): A predetermined polymer additive is added to and mixed with the kneaded product obtained in step (a). (C): Polymer 100 is added to the mixture obtained in the step (b).
50 to 75 parts by weight of cork crushed pieces are mixed with parts by weight, and the sheet is appropriately thickly sheeted. (D): The sheet obtained in the step (c) is compressed and vulcanized (or crosslinked) under appropriate conditions. A method for producing a cork-made vent body, which comprises the following steps. (A): 50 to 100 parts by weight of polyamide fiber is kneaded with 100 parts by weight of polymer. (B): Polymer 100 is added to the kneaded product obtained in step (a).
50-75 parts by weight of the cork shards are mixed with parts by weight. (C): A predetermined polymer additive is added to and mixed with the mixture obtained in the step (b), and the sheet is appropriately thickened. (D): The sheet obtained in the step (c) is compressed and vulcanized (or crosslinked) under appropriate conditions.

In carrying out the present invention, the polymer is natural rubber, styrene-butadiene copolymer rubber, polyisoprene rubber, polybutadiene rubber, acrylonitrile-butadiene copolymer rubber, synthetic rubber such as polychloroprene rubber, vinyl acetate content of 25% or more. An ethylene / vinyl acetate copolymer or the like is used. Polyamide fibers with a thickness of 3 to 30 denier and a length of 5 to 20 mm are used. If the thickness is less than 3 denier, it will be bulky if the required amount is added, and it will locally solidify in the kneading process of a roll machine etc. It is difficult to disperse, and if it exceeds 30 denier, it is difficult to cut into an appropriate length in the kneading step, only the polymer is kneaded without being curled, and it becomes difficult to disperse the compounded chemical in the following steps. Further, if the length is less than 5 mm, the sheet of the kneaded material is less likely to expand and become porous. On the other hand, if it exceeds 20 mm, it remains hard during kneading and is difficult to disperse. Polyamide fiber to 100 parts by weight of polymer
If it is less than 50 parts by weight, the air permeability will be impaired, and if it exceeds 100 parts by weight, it will be difficult to roll it into a sheet and it will be difficult to mix cork fragments. If the amount of crushed cork is less than 50 parts by weight with respect to 100 parts by weight of the polymer, the texture and appearance of cork are lost, and if it exceeds 75 parts by weight, the rolling property is poor and the dispersibility is significantly reduced.

At this time, the cork has an outer diameter of 0.5 to 5 mm.
If the outer diameter is less than 0.5 mm, the air permeability of the resulting air-permeable body is impaired, and if the outer diameter exceeds 5 mm, the surface becomes uneven and the appearance becomes poor. As for the order of addition and mixing of the polymer additives, when the decrease in the plasticity of the polymer during kneading is large, it is compared as early as possible, that is, after the polyamide fiber is kneaded with the polymer, and when the decrease in the plasticity is small. It is preferable that the polyamide fiber is kneaded with the polymer at an extremely late time, the cork fragments are mixed, and then the polymer additive is added and mixed.

[0007]

[Function] When polyamide fibers are kneaded with an unvulcanized or uncrosslinked polymer, shearing force is generated, the polyamide fibers are fibrillated, the aspect ratio is changed and they are dispersed uniformly at the same time, and the plasticity is also decreased. . When in a heat treatment state for vulcanization or cross-linking in such a state, the fibrillation is released, the aspect ratio is changed, an appropriate void is generated between the polyamide fiber and the polymer, and on the other hand, Where the voids do not occur, the physical properties of mechanical properties are brought about by the adhesion of the polymer polyamide fiber.

[0008]

【Example】

According to the compounding ratio, the polyamide fiber is dispersed and cut by kneading from the beginning without masticating with an open roll at 60 ° C. or less. This kneading time is 10 minutes, and after leaving it at room temperature for a whole day and night, it is kneaded again for 5 minutes to sufficiently disperse the polyamide fibers. Subsequently, polymer additives such as zinc white, powdered sulfur, vulcanization accelerator, stearic acid, and antioxidant are rapidly added and mixed, and finally, cork shavings are mixed to obtain a thickness of 7
Seat to mm.

The sheet thus obtained was vulcanized by a press at a pressure of 3 kg / cm ² , a hot plate temperature of 130 to 140 ° C., and a time of 6 minutes, and the NO.1 composition had a thickness of 5 mm and NO.2. Formula is thickness
A 5.5 mm sheet was obtained. As a control example, a commercially available cork sheet was used, and a physical property test (Table 1) of each sheet was performed. * 1: From tensile strength to hardness, JIS K6301 vulcanized rubber test method was used, and the aging condition was 85 ° C x 96 hours. * 2: According to JIS L1096-A method (flange seal type tester).

[0010]

[Effect] A sheet having higher mechanical strength and excellent breathability than the cork sheet used in the past was obtained. This sheet has exactly the same appearance and texture as conventional cork sheets. For example, sheets used for the insole / insole of shoes, the insertion / removal of pushpins as bulletin boards, the bottom surface of portable calculators, the back surface of various instruments, etc. Especially suitable in all respects.

[Table 1]

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Claims (2)

[Claims] 1. A method for producing a cork-made ventilation body, which comprises the following steps. (A): 50 to 100 parts by weight of polyamide fiber is kneaded with 100 parts by weight of polymer. (B): A predetermined polymer additive is added to and mixed with the kneaded product obtained in step (a). (C): Polymer 100 is added to the mixture obtained in the step (b).
50 to 75 parts by weight of cork crushed pieces are mixed with parts by weight, and the sheet is appropriately thickly sheeted. (D): The sheet obtained in the step (c) is compressed and vulcanized (or crosslinked) under appropriate conditions. 2. A method for producing a cork-made vent body, which comprises the following steps. (A): 50 to 100 parts by weight of polyamide fiber is kneaded with 100 parts by weight of polymer. (B): Polymer 100 is added to the kneaded product obtained in step (a).
50-75 parts by weight of the cork shards are mixed with parts by weight. (C): A predetermined polymer additive is added to and mixed with the mixture obtained in the step (b), and the sheet is appropriately thickened. (D): The sheet obtained in the step (c) is compressed and vulcanized (or crosslinked) under appropriate conditions.