JP2978958B2 - A method for producing a rolled outer sole made of foamed rubber and shoes having the same. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolled outsole made of foamed rubber and a method for producing shoes using the same.

[0002]

2. Description of the Related Art Shoes having a calendered outer sole are made by masticating natural rubber or synthetic rubber or a blend rubber of the two rubbers, and vulcanizing agents, vulcanization accelerators, fillers,
A reinforcing agent, an antioxidant, a softening agent, etc. are sequentially added to form a kneaded rubber, which is then aged at room temperature for about one day, rolled to a substantially outer bottom thickness by a calender, and cut into an outer bottom shape by a blade. Then, the lower surface of the upper hanged on the last is brought into contact with an adhesive, and is pressurized and heated in an indirect vulcanizing can to vulcanize the adhesive and the outer bottom.

[0003] Since the conventional kneading rubber used for the outer sole is for solid rubber (solid rubber), it has a large specific gravity when used in shoes, increases the weight of the product, lacks cushioning properties, and is poor in summer. It has drawbacks such as the heat on the sidewalk is easily transmitted, the soles become hot, and the amount of material used cannot be reduced. Therefore, kneaded rubber for foamed rubber is used as kneaded rubber in order to solve the above-mentioned drawbacks.

[0004] However, in the conventional compounding for foamed rubber, a rolled sheet is cut into an outer bottom shape with a blade,
The outer bottom expands in a three-dimensional direction when the lower surface of the upper suspended from the last is brought into contact with an adhesive and vulcanized between the adhesive and the outer bottom by applying pressure and heat. That is, the expansion occurs also in the length direction and the width direction of the outer sole, and it is not possible to limit the expansion to only the intended thickness direction, and the shoe becomes a warped shape as a whole,
The actual situation is that the shoe cannot maintain its original shape and cannot be put to practical use. The present invention has been made in view of the above circumstances, and has been made of a foamed rubber that can reliably retain its original shape even after it has become a product.
An object of the present invention is to provide a rolled outer sole and a method for producing shoes using the same.

[0005]

The present invention SUMMARY OF] is a rubber blend of natural rubber or synthetic rubber or the both rubber, short fibers and foaming agent is included as an essential component, the short fibers
Orientation direction is mostly the outer bottom length direction,
Intersects with the fiber oriented in the length direction and crosses the width of the outer bottom
The first feature is the oriented outer bottom made of foamed rubber.
A second feature of the shoe according to the present invention is a method of manufacturing a shoe having a foamed rubber rolled outer bottom by pressing the foamed rubber rolled outer sole against the lower surface of the upper, and applying pressure and heat.

In practicing the present invention, polyamide fibers, polyester fibers, glass fibers, carbon fibers, natural fibers, and cellulose fibers are used alone or in combination as the short fibers. It does not expand in the direction and width direction, but expands only in the thickness direction. Among them, the former three in which the foaming state is uniform are preferable.

[0007] Of the six types of short fibers, four types excluding carbon fibers and glass fibers have a length of 2.0 to 10 mm,
Those having a diameter of 0.5 to 15 denier are used, and within this range, the expansion in the length direction and the width direction is reliably prevented. And the air that escapes along the surface due to too much fiber is reduced, the expansion is not reduced, and the kneading can be done smoothly, and the physical properties of the outer bottom after completion are good. . Such an effect can be achieved with glass fibers and carbon fibers having a length of 2.0 to
The same is true for a range of 10 mm and a diameter of 5 to 20 microns.

Further, by adding 3 to 50 parts by weight of the short fibers to 100 parts by weight of natural rubber or synthetic rubber or a blend rubber of the two rubbers, there is no expansion in the length direction and the width direction, It expands only in the thickness direction, has good kneading operation, and has moderate physical properties as the outer bottom.

As the foaming agent, conditions for indirect vulcanization of the outer bottom of the roll made of foamed rubber, for example, the most commonly used air pressure of 2.0
~3.0Kgf / cm ^2, temperature of 120 to 130 ° C., suitable time 40-50 minutes azodicarbonamide (ADC
A), dinitrosopentamethylenetetramine (DP.
T) is used, but is not limited thereto.

The short fibers and the foaming agent are essential components for the rubber, but optional components include a vulcanizing agent, a vulcanizing agent and a vulcanizing agent in consideration of kneading, vulcanization degree and physical properties after vulcanization. Accelerator,
Vulcanization aids, fillers, reinforcing agents, antioxidants, softeners, pigments and the like are appropriately selected and used.

[0011]

When the outer bottom of the foamed rubber roll according to the present invention is in contact with the lower surface of the upper, the short fibers are mostly and partially rolled in a rolling direction by a calendering machine. Since the fibers are oriented in the direction crossing the direction, the direction of these short fibers almost coincides with the length direction and the width direction of the outer bottom, so that the length direction in the pressing and heating process at the time of indirect vulcanization. In addition, it acts to suppress expansion in the width direction and prevents expansion. However, since it is not oriented in the thickness direction, it expands in this direction, and the desired outer rolled outer sole made of foamed rubber and shoes having the same can be obtained.

[0012]

EXAMPLE The following operation was carried out, and the outer bottom of the foamed rubber roll was
And shoes using it. First, rubber was masticated by reducing the roll interval of a roll machine. Next, the roll interval is increased, and a kneaded material is prepared by adding a foaming agent, various fibers, and other rubber additives, aged at room temperature (20 ° C.), and a calender having a concave and convex design of the outer bottom grounding surface is used. .3m
m.

The rolled sheet is cut with an outer bottom blade die, and is 250 mm long, 80 mm longest and 55 m shortest.
m of the unvulcanized outer bottom was placed in an indirect vulcanizer, and vulcanized at a temperature of 125 ° C., an air pressure of 2.5 kgf / cm ² , and a time of 30 minutes. This foamed rubber outer bottom expands sufficiently in the thickness direction to form a foam in indirect vulcanization,
It was found that the outer bottom did not expand in the length and width directions.

[0014] Then, the lower end of the vulcanized outer sole was brought into contact with the lower surface of the upper suspended from the last using a polychloroprene-based adhesive, and indirectly vulcanized under the vulcanizing conditions to produce shoes. The shoes were allowed to stand at room temperature (20 ° C.) for 6 months, but did not warp and maintained a good shape.

Claims (6)

(57) [Claims] 1. A natural rubber or a synthetic rubber or a blend rubber of the two rubbers contains a short fiber and a foaming agent as essential components, and the orientation direction of the short fiber is mostly outside.
In the longitudinal direction of the bottom, a part of the fiber is oriented in the longitudinal direction.
A rolled outer bottom made of foamed rubber , characterized by being oriented in the width direction of the outer bottom crossing with the fiber . 2. The rolled outer bottom made of foamed rubber according to claim 1,
A method for producing a shoe having a rolled outer sole made of foamed rubber, wherein the shoe is brought into contact with the lower surface of the upper and pressurized and heated. 3. The foamed rubber according to claim 1, wherein the short fiber is any one of polyamide fiber, polyester fiber, carbon fiber, glass fiber, natural fiber, and cellulose fiber, or a combination of two or more thereof. Rolled outer bottom. 4. The staple fiber according to claim 1, wherein the polyamide fiber, polyester fiber, carbon fiber and cellulose fiber have a length of 2.0 to 10 mm and a diameter of 0.5 to 15 denier. Rolling of foamed rubber described in 3
Outsole. 5. The foam according to claim 1, wherein carbon fibers or glass fibers among the short fibers have a length of 2.0 to 10 mm and a diameter of 5 to 20 microns.
Rubber rolled outer bottom. 6. The staple fiber according to claim 1, wherein the staple fiber is added in an amount of 3 to 50 parts by weight based on 100 parts by weight of natural rubber, synthetic rubber or a blend rubber of the two rubbers. or 5 calling is any one of, wherein
Outer bottom made of foam rubber.