JPS59168801A - Production of 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 invention relates to a method for manufacturing injection molded shoes, and in particular, to a method for manufacturing injection molded shoes, in particular, it integrates a heel reinforcing moon shape into a desired shape during injection molding of a ground sole, and also firmly molds it to a predetermined location on the inner surface of the heel. This article relates to a manufacturing method for injection molded shoes.

The heel-sleeve strong moon shape allows the heel of the wearer's foot to fit comfortably into a predetermined location on the inner surface of the shoe's heel, creating a stable condition, allowing the wearer to move easily and quickly while walking with good balance, and always It is used to maintain the beautiful shape of the heel area of shoes.

Conventionally, a heel reinforcing piece in the shape of July was placed on the inner surface of the heel of injection molded shoes.
A variety of methods have been proposed to achieve this.

For example, the bottom of the ground can be covered in a short period of about a few minutes.
As an injection molding method such as that described above, a method using a heel reinforcing moon mold made of cloth and thermoplastic resin has been proposed.

However, in the above-mentioned method that has been proposed conventionally, the heel reinforcement moon shape is heated to a relatively high temperature of 720 to 2θ0°C, and a styrene-book diene blank copolymer, poly-Kurekune Elas 1, which becomes thick and sticky, is used. -Thermoplastic resins such as mer were used.

In the injection molding process, the shoe last cannot be heated to such a high temperature due to the cooling cycle and the suspension operation of the shoe cover, so a reinforcing mold that softens at 720 to 200 degrees Celsius is used. This method has the disadvantage that the mold needs to be softened and made sticky, and the number of steps increases.

The purpose of the present invention is to eliminate all the drawbacks of the conventional methods as described above. This was achieved by combining a thermoplastic resin that softens at θ to 90°C and a thermal nJ plastic resin that softens at temperatures between θ and 90°C.

More specifically, the heel part used in the present invention is sequentially laminated, and the outer surface of the thermoplastic resin IH, which becomes sticky at temperatures of θ to 9θ°C, is layered on the inner surface of the heel. The object of the present invention can be achieved by sewing the material in the 1" section and then performing injection molding to form the ground sole.

In the present invention, the shoe last is heated by an inserted heater etc.
The shoe last is heated to 90 degrees Celsius, and the thermoplastic resin layer that softens at 0 to 90 degrees Celsius retains the same shape as the shoe. At the same time, the outermost layer of fabric (that is, the fabric that is in direct contact with the shoe last) is also bonded to the heel part of the inner surface of the shoe, and after the injection of the ground sole material into the hollow part is completed, the heel part is The moon mold provides strong adhesion and fixes the thermoplastic resin layer in the desired shape.

On the other hand, normally it is considered to keep the shoe last as low as possible to increase the cycle of injection molding, but if the lower mold is sufficiently cooled, the temperature of the shoe last can be kept at 0-90℃. There is no noticeable increase in the molding cycle, and there is no particular hindrance to the operation of hanging the shoe last.

Especially in the present invention, the worker may get burnt or
1ll breakage will not cause damage or discoloration] Of course 9, attach the heel strong moon shape to the inner surface of the heel A: f shi,
In addition, no special heating equipment or process is required to form the desired shape, and the equipment cost is simplified, and at the same time, the manufacturing cost is reduced.

f6J, in carrying out the present invention, Otsu θ~ and 0℃
Polymethylene terephthalate having a hydroxyl group or carboxyl group (1) at the end of the molecule is used as the thermoplastic resin that becomes sticky.
J.
Melting viscosity at 0°C Xθθ0~. 2,000 voids and a melting point of /10 to /2°C are optimal. As the thermoplastic resin which softens at 60° C. to 0° C., an ethylene-hinyl acetate copolymer containing: 2% by weight of hinyl acetate is used.

As shown in Figure 7, a piece of fabric cut into two moon-shaped pieces was mixed with toluene and 7 methyl ethyl ketone at a ratio of θ/20 on one side. Polymethylene terephthalate (molecular weight approximately 20θθθ, melt viscosity at 200°C, 4 and θO poise, deformation ηP/10°C) having a hydroxyl group and a carboxyl group in A1.1 dissolved in a solvent is poured into a thin layer of 75θ microns. (2), and on the 121st side of the thin layer, an ethylene-hynyl sulfate copolymer layer (3) with a hinyl acetate content of 72%/+2% is laminated, and the copolymer layer (3) Layer the same solution used for the thin layer (2) on the surface to form a thin layer (4) of 70θ microns,
Obtain a moon shape (5) for strong heel area.

As shown in Figure 2, the moon type 15) for reinforcement
17) Sew on the heel part of the side surface with the bottom cloth 0■ by twisting it with the auxiliary layer (4), and heat this cover 16) to about 7θ℃ with an inserted heater (commercial cover). Hang it on the shoe last (8).

As shown in Figure 3, this shoe last (8) is combined with a side mold (9) and a bottom mold (01) consisting of a bottom mold of 0σ, and molten polyvinyl chloride (12) at 0°C is injected. The cavity 04) is injected through the hole θ (8) to fill it, and the shoe last (
The heat-adhesive thin layer (2) of step 8) completely adheres the fabric () and the ethylene-vinyl acetate copolymer layer (3);
This orthodontic body is covered with a thin layer (4) which is also made of adhesive.
6) Adhere the ethylene-vinyl acetate layer ifi (l = layer [3), which is adhered to the inner surface and softened at the same time, to the same shape as the heel part of the shoe last (8), and apply it to the desired shape. I got injection molded shoes with strong moon shape.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the moon-shaped heel part used in the present invention, Figure 2
Figure 3 is a cross-sectional view showing the method for manufacturing injection molding according to the present invention.
Polymethylene ethylene reflex acid thin film having a former hydroxyl group and a carboxyl group, (3)...Ethylene-vinyl acetate copolymer layer, 15)...Moon shape for reinforcing the base, (6 )...Tsu II +7)...Nui>Q +
(8!...shoes 5, 19)...side type, jl
f))... lower mold, 01)... grounded bottom mold,
(121...Polychlorinyl chloride, 03)...Injection hole, 0.O...Void part, 0■...Bottom cloth. M Applicant Tsukiboshi Kasei Co., Ltd. Figure 1 Figure 3

Claims (1)

[Scope of Claims] Fabric, polymethylene terephthalate thin layer having hydroxyl groups and carboxyl groups at the ends, vinyl acetate content /θ ~ / 2: M f, H 0% ethylene-hinyl acetate co-rectangle 2 , 14. Polymethylene ethylene terephthalate having a hydroxyl group and a carboxyl group at the end of the layer.
At the end of it'll and ii8, there is a polymethylene ethylene terephthalate oil layer having a 1-glycyl group and a carboxyl group at the needle part of the inner wall of the 11th carapace? C convex *7fJ, shi, and flit' are suspended into a 'standing mold at θ ~ 90℃, combined with a grounded bottom mold, and IW J'L la is placed in the cavity formed at that time.
Inject 4"i fat and mold the 11/11 plate bottom + r eyebrow ground bottom, integrate the 1 reinforcing moon shape () and mold it into the desired shape, and at the same time attach it to the 1n1 inside the crack. A commercial law for injection molded shoes, which is characterized by: