JP2001346608A - Injection molded shoes and manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide injection molded shoes, flexible and excellent in keeping shape, which hardly deform after a long use, well fitted feet. SOLUTION: With the injection molded shoes whose instep cover material is made of synthetic leather, a core material used for a toe box or a shoe counter for the instep cover consists of an unvulcanized rubber sheet containing vulcanized agent or an unvulcanized rubber sheet reinforced with butter muslin buried inside, which is vulcanized before or after the injection molding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection-molded shoe which is flexible and excellent in shape retention, and hardly loses its shape even when worn for a long time. That is, the present invention relates to an injection-molded shoe that is less likely to cause laughter and a manufacturing method thereof.

[0002]

2. Description of the Related Art In a shoe upper used for injection-molded shoes, an EVA tip, a urethane tip, and a Surlyn tip are used as a core, and a moon type is an EVA moon type, a thermo counter. And a thermoplastic resin material such as VIX Rex (trade name). Injection molding shoe molding, counter dresser before hanging the shoe upper of the above configuration on the injection molding last, or by performing injection molding without setting the counter front by heating the injection molding last. I have.

[0003]

However, when the core material described above is used for shoes, it is less familiar with the last shape as compared with a vulcanized product which generally vulcanizes an unvulcanized rubber core material. In addition, the core material has no elasticity, so it is easy to lose shape by stepping on the heel or absorbing the sweat in the shoes while continuing to wear for a long time, and it is difficult to return to the original shape once it collapses was there.

An object of the present invention is to solve the above-mentioned drawbacks of the well-known technique, and to provide an injection-molded shoe which has good shape retention and is less likely to lose its shape, and a method of manufacturing the same.

[0005]

SUMMARY OF THE INVENTION An injection-molded shoe according to the present invention is an injection-molded shoe in which a bottom material is in contact with a lower surface of a cotton or synthetic leather shoe upper, and a lug for use in the shoe upper. The core material including the leading core is a kneaded product containing sulfur as a vulcanizing agent in a rubber component mainly composed of a diene rubber, and has a heating temperature of 80 to
It is characterized by being vulcanized at 130 ° C.

The injection-molded shoe according to the present invention is characterized in that an unvulcanized rubber sheet is laminated on both sides of a mesh base cloth in the core material including the moon mold and the leading core. Molded shoes.

According to the method of manufacturing an injection-molded shoe of the present invention, a front core and a lug made of an unvulcanized rubber sheet are attached to a shoe upper, and an insole is sewn around the lower periphery of the shoe upper. After forming the bag-shaped shoe upper cover and suspending the bag-shaped shoe upper cover on aluminum rust, heating at 80 to 130 ° C., vulcanizing the leading core and the moon mold, and then removing the mold, The bag-shaped shoe upper is hung on the injection molding last, and the last, the side molding ゛, and the sole mold are combined to form a shoe sole molding cavity, and the injection molding material is injected into the cavity. It is characterized by the following.

According to the method of manufacturing an injection-molded shoe of the present invention, a front core and a lug made of an unvulcanized rubber sheet are mounted on a shoe upper, and the shoe upper and the midsole are suspended on aluminum rust with adhesive. After that, it is heated at 80 to 130 ° C., and after vulcanizing the leading core and the moon mold, the mold is released, and the bag-shaped shoe upper is hung on the injection molding last. It is characterized in that a cavity for molding a shoe sole is formed in combination with a sole mold, and an injection molding material is injected into the cavity.

According to the method of manufacturing an injection-molded shoe of the present invention, a front core and a moon made of an unvulcanized rubber sheet are attached to a shoe upper, and an insole is sewn to the entire lower periphery of the shoe upper. A bag-shaped shoe upper is formed, the bag-shaped shoe upper is hung on a last for injection molding, and this last is combined with a side molding and a sole mold to form a cavity for forming a shoe sole. After injecting the injection-molded material into the cavity, the molded shoe was die-cut, the shoe described above was hung on aluminum rust, heated at 80 to 130 ° C, and the tip core and the moon mold were vulcanized. It is characterized by the following.

The rubber core material for an injection-molded shoe of the present invention is used as a core or a lug, and the core material is sewn to the upper in an unvulcanized rubber state in the same manner as in the method of manufacturing a vulcanized type general cloth shoe. By attaching the shoe cap to the last mold with a counter dresser, suspending and vulcanizing, and then molding by injection molding, shoes that are faithful to the last and have a sharp mouthpiece shape can be obtained.

[0011] In the heating step, pressure may be applied before bottoming, but pressure should not be applied when performing the heating step after injection molding of the shoe sole. When heating is performed by applying pressure, the sole of the shoe is deformed, resulting in a defective product. In addition, the heating temperature at that time is preferably 80 to 130 ° C. If the heating temperature is lower than 80 ° C, a long heating time of the core material is required. If the heating temperature is higher than 130 ° C, the shoe upper may be used. It may cause damage to the material.

[0012] In the core material of the present invention comprising a lug and a core, the lug and the lug have an unvulcanized rubber sheet laminated on both sides of a mesh base cloth. A method for producing an injection-molded shoe according to claim 5. The core material of the present invention can provide a shoe excellent in resilience and setability by using a core material in which a mesh cloth such as a cold gauze is sandwiched between rubber sheets as a reinforcing cloth.

The diene rubber which is the main component of the rubber core material for injection molded shoes in the present invention is a natural rubber, an isoprene rubber,
Materials having excellent rubber elasticity such as styrene-butadiene rubber, butadiene rubber, syndiotactic 1,2-polybutadiene rubber, acrylonitrile-butadiene rubber, and styrene-butadiene-based thermoplastic elastomer are exemplified.

The hardness of the rubber core material can be adjusted by the compounding amount of the filler, and a soft type can be obtained by using a small amount of the filler, and a hard type material can be obtained by using a large amount of the filler. . Examples of the filler include calcium carbonate, magnesium carbonate, basic magnesium carbonate, white carbon, zinc white, hydrous silicic acid, calcium silicate and the like.

In producing the rubber core material for injection-molded shoes of the present invention, sulfur is used as a crosslinking agent. In the case of sulfur crosslinking, powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur and the like can be used, and various vulcanization accelerators may be added at the same time. Specific examples of the vulcanization accelerator include diphenyl guanidine, di ortho tolyl guanidine, 2-mercaptobenzothiazole, dibenzothiazole disulfide, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, and the like.
It is not particularly limited as long as it contributes to vulcanization of a diene rubber or the like.

If necessary, in addition to the above-mentioned compounding agents, a crosslinking aid, an activator, an antioxidant, a wax, a processing aid and the like may be appropriately added. The method of mixing the compounding agents is not particularly limited, and a mixing method used for general rubber compounds such as a Banbury mixer, a pressure kneader, an open roll, and the like can be used.

The bottom material to be injection-molded is usually used polyurethane (ester type, ether type), polyvinyl chloride, or TPR or TPE which is currently attracting attention as a non-PVC type material. It is not something to be done.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Injection molded shoes having the structure shown in FIG.
The following is a description of the manufacturing process of shoes manufactured by using the rubber moon type (3) of the present invention and the shoes manufactured by using the EVA moon type (7) which has been conventionally used, and the contents of a comparative study thereof.

After kneading the polymer component and other additives according to the composition shown in Table 1, the unvulcanized rubber (2) was topped by using Kansa (1) as a reinforcing cloth. After that, the uncured rubber (2) topping process is performed on the surface of the cold sand (1), and the cold sand (1) is applied to the uncured rubber (2) sheet.
And a rubber core material sheet for injection-molded shoes having a thickness of 1.5 mm was produced. Later, it was punched out with a blade mold to obtain a rubber moon mold (3). Heel cover (4) and back cover (5)
The rubber lug (3) is inserted between them, sewed with a sewing machine, heated and cooled with a counter-dresser, knitted, sewn on the insole (6), hung on the last,
After vulcanization at 45 ° C. for 45 minutes under no pressure, the sole was vulcanized by an injection molding method to obtain an injection molded shoe of the example.

[0020]

[Table 1]

As a comparative example, a conventional EVA lunar type (7) was inserted between the upper cover (4) and the back cover (5) of the heel and then sewed with a sewing machine to form a counter dresser. After heating, cooling and knitting, sewing the insole (6), hanging it on the last, performing heat setting at a temperature of 100 ° C. for 60 minutes, and then bottoming it by injection molding. Was carried out to obtain an injection molded shoe of a comparative example.

The injection-molded shoes of the embodiment using the lunar mold made of the rubber sheet for the injection-molded shoes of the present invention and E which have been conventionally used.
In the injection molded shoes of the comparative example using the VA moon type, a comparison was made between the shape after molding and the shape of the mouth after the shoes were worn one by one on the left and right sides and the test shoes were worn for about one month. Are shown in Table 2.

[0023]

[Table 2] ◎: Very good ○: Good ×: Poor

The shape of the injection-molded shoes of the example was more faithful to the shape of the last than the injection-molded shoes of the comparative example, and the shape of the mouthpiece was sharp. Also, in the test shoes, the mouth of the injection molded shoe of the comparative example laughed in two weeks, and after one month, the mouth was laughing and the shape collapsed or partially bent compared to the conventional shape of the moon type after one month Some parts were seen. However, the injection-molded shoes of the examples maintained the lunar hardness and did not collapse in the shape of the mouthpiece.

[0025]

[Effect] In an injection-molded shoe in which a bottom material is in contact with a lower surface of a cotton cloth or synthetic leather shoe upper, a core material used for a leading core or a moon shape of the shoe upper is an unvulcanized rubber sheet or By using a rubber core material in which an unvulcanized rubber sheet is laminated on both sides of the mesh base fabric, an injection molded shoe that is faithful to the last shape can be obtained even in a product shape which has been a problem in the past. Even when worn for a long time, the shape is reduced and the shape retention is improved, and even if you step on the heel, it returns well, making it possible to wear comfortably forever.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a heel portion of a shoe.

FIG. 2 is an enlarged view of a heel vertical section of a shoe of a comparative example.

FIG. 3 is an enlarged longitudinal sectional view of a heel portion of the shoe of the embodiment.

[Explanation of symbols]

 1. Kansha 2 2. Unvulcanized rubber Rubber moon type 4. Omikaba 5. Back shell 6. Insole 7. 7. EVA moon type Moon type

Claims (6)

[Claims] 1. An injection-molded shoe in which a bottom material abuts on a lower surface of a cotton cloth or synthetic leather shoe upper, wherein a core material including a lug and a front core used for the shoe upper is made of diene rubber. An injection-molded shoe, which is a kneaded product containing sulfur as a vulcanizing agent in a rubber component as a main component and vulcanized at a heating temperature of 80 to 130 ° C. 2. The injection-molded shoe according to claim 1, wherein the core material including the moon and the leading core has an unvulcanized rubber sheet laminated on both sides of a mesh base cloth. 3. A boot and a lug made of an unvulcanized rubber sheet are attached to a shoe upper, and a middle sole is sewn around the lower periphery of the shoe upper to form a bag-like shoe upper. After hanging the bag-shaped shoe cap on aluminum rust, heating at 80 to 130 ° C., vulcanizing the leading core and the moon mold, removing the mold, and injecting the bag-shaped shoe cap. The injection molding shoe is characterized in that it is hung on a molding last, forms a cavity for shoe sole molding by combining this last, a side molding and a sole mold, and injects an injection molding material into the cavity. Production method. 4. A core and a lug made of an unvulcanized rubber sheet are attached to a shoe upper, and the shoe upper and the midsole are hung on aluminum rust with adhesive glue. After heating and vulcanizing the front core and the moon mold, the mold is released, the bag-shaped shoe upper is hung on the last for injection molding, and the last is combined with a side molding and a sole mold to form a shoe sole. A method for producing an injection-molded shoe, comprising: forming a cavity for injection; and injecting an injection-molded material into the cavity. 5. A front core and a lug made of an unvulcanized rubber sheet are attached to a shoe upper, and a middle sole is sewn around the lower periphery of the shoe upper to form a bag-like shoe upper. The bag-shaped shoe upper is hung on the last for injection molding, and the last, the side molding and the sole mold are combined to form a cavity for shoe sole molding, and the injection molding material is injected into the cavity. After that, the molded shoe is die-cut, the shoe described above is hung on aluminum rust, heated at 80 to 130 ° C., and the tip core and the moon mold are vulcanized. Production method. 6. The method for producing an injection-molded shoe according to claim 3, wherein the lunar mold and the leading core have an unvulcanized rubber sheet laminated on both sides of a mesh base cloth.