JPS61302A - Production of antistatic injection molded shoes - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing antistatic injection molded shoes.

With the development of petrochemistry, highly insulating synthetic resins, synthetic fibers, etc. have become widespread, and as a result,
Accidents due to static electricity charging tend to occur frequently.

The same applies to the human body, and therefore antistatic shoes with conductivity are used.

Generally, when attempting to manufacture a large quantity of shoes at a relatively low cost, injection molding is generally used, and the same can be said of antistatic shoes as described above.

Conventionally, a few methods have been proposed for obtaining antistatic shoes by injection molding, and shoes obtained by these methods are actually used.

For example, a layer of conductive printing ink is applied to the side of the insole fabric that does not contact the sole of the foot, which is made of mixed fibers with conductive fibers exposed on both sides, so as to cover only the exposed conductive fibers. Antistatic injection molding obtained by sewing on the lower periphery, suspending this cover on a shoe last, combining it with a sole mold having a sole cavity, and injecting a conductive sole material into the cavity. Shoes are suggested.

Shoes obtained by this method use components with excellent conductivity, such as the insole fabric, conductive print ink layer, and conductive sole material, so they have the electrical resistance necessary for antistatic shoes. Although it can be easily adjusted to fall within the range of 105 to 108 ohms, the conductive printing ink layer is applied only to a specific part of the surface of the insole fabric that does not contact the sole of the foot, that is, the exposed surface of the conductive fibers. The application process is time-consuming, and since the surface in contact with the sole of the foot is in contact with the conductive part only through exposed conductive fibers, the insole fabric must be mixed with a large amount of conductive fibers, which makes the process difficult. It has the disadvantage of being relatively expensive both from the perspective of the material and from the perspective of the materials used.

The present invention aims to eliminate the drawbacks of conventional antistatic injection molded shoes as described above.
For this purpose, conductive glue of almost the same color as the insole fabric is applied to the side of the insole fabric that does not contact the sole of the foot so that it oozes out onto the side that is in contact with the sole of the foot, and then sewn around the lower edge of the shoe. This was achieved by manufacturing an injection-molded shoe by suspending this shoe cover into a shoe last, combining it with a sole mold having a sole cavity, and injecting a conductive sole material into the cavity. It is.

The above-mentioned insole fabric used in the present invention is a single-layered one coated with conductive glue of approximately the same color as the insole fabric on the side that does not contact the sole of the foot, and a single layer that has a conductive glue coated with almost the same color as the insole fabric on the side that does not contact the sole of the foot. A plurality of fabrics coated with conductive glue of approximately the same color as the insole fabric and then laminated with coarse fabric such as sackcloth, cheesecloth, etc. that allows the conductive shoe sole material to pass through sufficiently during injection molding, or both. This includes:

The conductive glue may be non-black in color and has an electrical resistance within the range of 105 to 108 ohms required for shoe soles, and is usually made of polyurethane, polyvinyl chloride, vinyl chloride-acetic acid. Vinyl copolymers, mixtures thereof, and the like are used, and antistatic agents such as surfactants, quaternary ammonium salts, and polyhydric alcohol derivatives are added. Further, as the inner sole cloth, a normal cloth without conductive fibers mixed therein is used, but there is no problem in using a cloth with some conductive fibers mixed therein as long as the price does not become high.

In the present invention, the conductive glue applied to the surface not in contact with the sole of the foot exudes from the surface of the insole fabric that comes into contact with the sole of the foot, so the sheet metal and the insole fabric themselves have almost no conductivity. However, the conductive glue that oozes out ensures the conductivity necessary for the sole of the shoe. In this case, as long as conductive fibers are mixed in the insole fabric within a range that does not increase the price, it is possible to further impart conductivity to the sole without impeding the object of the present invention. Furthermore, it is not necessary to selectively apply conductive glue to the surface that does not contact the sole of the foot, as was done in the manufacturing process of the conventional conductive injection molded shoes, only to the exposed parts of the conductive fibers. Since it is sufficient to uniformly coat the entire surface, no effort is required and the process is simple. Furthermore, the conductive glue that oozes out from the surface that comes into contact with the sole of the foot can be freely selected from a non-black color to match the insole fabric, which is not the case when wearing shoes that have been proposed in the past. Phenomena such as contamination of the wearer's socks can be avoided.

Example conductive shoe sole material <ivxm<-x, p, 12.000)
"" Mirable urethane chloride and ni-vinyl acetate copolymer 40〃Calcium carbonate 100
〃Plasticizer DBP 35 〃Quaternary ammonium salt
10 Titanium oxide
2 "The above formulation was kneaded using a roll machine, and the kneaded product was dissolved in U-ruethyl ketone to a solid content of 45χ to obtain a paste.

This glue was uniformly applied to the entire surface of a white cotton insole fabric mixed with 0.1x carbon fiber that did not contact the sole of the foot, and a piece of cotton cheesecloth was placed over the coated surface and dried. At this time,
On the surface of the insole fabric that was in contact with the sole of the foot, glue was seeping out evenly in the form of dots. This was sewn to the lower periphery of a double-woven cotton cover to obtain a bag-stitched press ring, which was hung from a shoe last. .

This shoe last was combined with a sole mold heated at 180° C., and the following conductive sole material compound was injected into the sealed cavity of the sole mold for 4 minutes, and then taken out and cooled to obtain a shoe.

Conductive sole side compounded polyvinyl chloride (thing-1,000) 100
Parts by weight Plasticizer DBP 40 Plasticizer DOP 50 Calcium carbonate 40
〃Quaternary ammonium salt
2 # As mentioned above, in the manufacturing method according to this example, the conductive glue only needs to be uniformly applied to the entire surface of the white insole fabric that does not contact the sole of the foot, so no effort is required. In addition, since only a small amount of carbon fiber is mixed into the white insole fabric, it has little effect on the price, and the electrical resistance of the sole is 10 foam (JIS).
T 8103 according to the second test method), and had sufficient performance as antistatic shoes, and did not become contaminated even when worn for a long time with inner socks.

Claims (1)

[Claims] Applying conductive glue of approximately the same color as the insole fabric to the side of the insole fabric that does not come into contact with the sole of the foot so that it oozes out onto the side that comes into contact with the sole of the foot,
A conductive shoe sole material is sewn to the lower periphery of a shoe sole, the shoe shoe is hung on a shoe last, the shoe sole is combined with a sole mold having a hole in the sole, and a conductive sole material is injected into the hole. Prevention injection molding shoe manufacturing method.