JPS59209302A - 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 present invention relates to a method of manufacturing a shoe having a lightweight outsole, and more particularly, to a method of manufacturing an injection molded shoe having a sole that is lighter than a so-called stolen design.

In recent years, shoes, especially injection molded shoes, are desired to be lightweight, so as shown in Figure 1, a front cross-section of a conventional example attached to the last, injection molded shoes (1) have an outsole (2) and a straight design (3). ) (referring to holes or recesses for weight reduction; the same applies in this specification), and injection-molded shoes (not shown) in which the sole of the injection-molded shoe is made of a foam material. There are injection molded shoes (not shown) in which the outsole itself is formed thin. Injection molded shoes with a stolen design include injection molded shoes with a stolen design on the last (4) side of the outsole (2) as shown in Figure 1, and injection molded shoes with a stolen design on the last (4) side of the outsole (2), as shown in Figure 1. Injection-molded shoes (not shown) are known that have a tampered design on the side, that is, the ground contact side, but the latter may have pebbles etc. stuck in the tampered design area during wear, or the tampered design (3). The former method is used to reduce the weight of injection molded shoes because it has the disadvantage of easily causing breakage. In the former case, that is, in the production of injection molded shoes having a slender design (3) on the last side of the outsole (2), it is necessary to provide a convex portion (5) on the bottom surface of the last, that is, the last (4).

By the way, in the manufacturing method of injection molded shoes, as is clear from FIG. 2, which shows a front cross-section of another conventional example in a state where it is attached to the last during the manufacturing process, instead of having an insole, a shoelace (6) is used. As is clear from FIG. 3, which shows a method of manufacturing injection molded shoes using a so-called string lace having a string (7) on the lower peripheral edge of the shoe, and a front cross-section of another conventional example in a state where it is attached to the last during the manufacturing process. In this method, a so-called California lace is used, in which the lace cover (6) and the inner sole (8) are sewn in a bag-like manner, with the local edge (9) of the sewn part of the lace cover and the insole facing outward of the injection molded shoe. Manufacturing method of injection molded shoes and Utility Model Opening 1977-1
As disclosed in Japanese Patent No. 8328, and as shown in FIG. 4, which is a front cross-sectional view of another embodiment attached to the last during the manufacturing process, the stitching of the sleeve cover (6) and the inner sole (8) The outer edge (9) of the shoe is folded towards the inside of the injection molded shoe.
There is a method of manufacturing injection molded shoes using a so-called reverse California stitch in which the inner sole (8) and the inner sole (8) are sewn together in a bag shape. In the method for manufacturing injection molded shoes (1) using string strings, the last (4) is tightened by tightening the string strings (7).
), so the cover (6) can be attached to the last (4) without covering the convex part on the bottom of the last (4). However, when attaching the string cord to the last (4), first pull the string cord (both ends of the force) to make the lower edge of the string cord (6) fit well with the last (4), and then In order to prevent the laces (6) from lifting up, the shoes had the disadvantage of requiring complicated work such as securing the string strings to the pins planted on the bottom of the last.On the other hand, injection molded shoes with California laces In the manufacturing method (1), the cover (6) and the insole (
8) is sewn into a bag shape, so it is easy to attach it to the last (4), but as shown in Figure 3, there is a stolen design (3).
If a convex portion (5) is provided on the last bottom surface to form a bottom surface, the peripheral edge (9) of the sewn portion will rise above the bottom surface of the last (4), so the local edge portion (9) of the sewn portion will be It had the disadvantage of being more easily exposed. In addition, injection molded shoes with so-called reverse California laces have a lace (6) on the outside of the periphery of the outsole when California laces are used for injection molded shoes with thin outsole.
This was devised for the purpose of eliminating the defect that the local edge (9) of the sewn portion between the inner sole (8) and the inner sole (8) protrudes.

Therefore, the reverse California lace is inferior to the California lace when it comes to sewing work between the insole and the lace, so the reverse California lace is used in the manufacturing method of injection molded shoes with a stolen design on the outsole. There was nothing to do.

In addition, in the manufacturing method of injection molded shoes using reverse California stitching, the local edges of the seams protrude on the inside, so
The disadvantage of using California laces is that the laces and the inner surface of the midsole do not come into close contact with the last.

Furthermore, Japanese Patent Application No. 57-12952 states, ``When manufacturing injection-molded shoes with an injection design, compared to the case where the insole is made of a knitted fabric with a fiber density as high as that of the insole, The disadvantage is that it becomes easy to deform, the lace material and the insole cannot be smoothly attached to the last, and the lace cover easily comes off from the end of the bottom surface of the last.

This invention provides a bottom surface that is lower than the convex part of the last, which has a convex part forming a stolen design on the bottom face, such as the peripheral edge part of the reverse California cone, which is formed into a bag shape with the peripheral edge part of the convex cover and the inner sole facing inward. Attach to the periphery, attach a cover to the last, mold the lower part of the cover and the middle sole to the last and the sides, seal with set mold 1, and fill the gap formed by the last and side mold with thermoplastic. It is an object of the present invention to eliminate these drawbacks by providing a method for manufacturing injection molded shoes, characterized in that the outsole is formed by injection injection of a resin compound.

In FIG. 5 showing a front cross-section of a state in which the embodiment of the present invention is attached to the last during the manufacturing process, and FIG. 6 showing a partially enlarged view of the middle bottom of FIG. Molded shoes, (2) is the sole, (3) is the stolen design, (6) is the cover, and (8) is the insole.

The outsole (2) is made by melt-injecting a thermoplastic synthetic resin compound, and the sleeve (6) has a high implant density (high fiber density).
Woven fabric (1! Cloth and woven fabric. All the same in this specification)
It becomes more. The inner sole (8) is made of knitted or woven fabric (low fiber density) with a low weft density (low fiber density) of 3/inch to 90 threads/1 inch each for weft and warp threads, such as cheesecloth, sackcloth, Indian head, muslin, and net. 10 and a thermoplastic synthetic resin compound coating (previously) is adhered to it. The thermoplastic synthetic resin compound coating (II) has a reinforcing effect and has a thickness of 0.
05m to 2, OOm), and as long as it has a reinforcing effect, the thermoplastic synthetic resin compound coating (11)
It may have pores corresponding to the composition gap of the textile fabric 0cm, or it may have pores partially. The insole (8) is made of an adhesive of the thermoplastic synthetic resin compound coating OD and the m-woven fabric +10+ with low implant density (low fiber density). (At the same time, the stretching and fraying of the thermoplastic synthetic resin compound coating (11) during heating is
) structure, and has the same strength as the plain woven fabric commonly used for the insole (8) that has been treated to prevent fraying, or injection molded shoes using laminated materials. Attaching the molded shoe (1) to the last (4) is easy. Thermoplastic synthetic resin compound coating (11
) must have a melt temperature equal to or lower than the melt-injected thermoplastic resin formulation forming the outsole (2).

In this example, the stitching between the cover (6) and the insole (8) is as follows:
As is clear from Figure 5, the outer side of the cover (6) and the inner sole (8)
) are sewn together, and the sewn local edges 19) of the shoe cover (6) and the midsole (8) face inward of the injection molded shoe (1), and the stitch cover (6) and the midsole (8) ) are sewn in the shape of a bag, and the local edge part (9) of the sewn part is attached to the periphery of the last (4) which has a concave part (5) for forming a stealth design on the injection molded shoe. Can be locked.

Therefore, in this Example f, the last (4) and the Sai P mold Q2. ．． FIG. 7 shows a front cross-section of the embodiment of the present invention installed in the N Tom mold (1), and FIG. 8 is a partially enlarged view of the main bottom and middle bottom of FIG. 7. At the periphery of the last (4) having a portion (5),
The sewing part (9) of the shoe cover (6) and the inner sole (8) are locked, the shoe cover (6) with the inner sole (8) sewn is attached, and the injection molded shoe (1) is assembled. Sai P mall)' (121, &
) A thermoplastic resin compound having a melting temperature equal to or higher than the melting temperature of the thermoplastic synthetic resin compound coating 01) which forms the inner sole (8) in the void 04) is injected into the gap 04). to form the outsole. Since the melting temperature of the thermoplastic synthetic resin compound coating (+1) forming the insole (8) is lower than the melting temperature of the thermoplastic synthetic resin compound coating forming the outsole, the melt injected into the void (14) The thermoplastic synthetic resin compound coating αυ on the insole (8) that came into contact with the thermoplastic resin compound softened, and therefore the injected molten thermoplastic resin compound was melted into the insole due to the heat and injection pressure of the injected molten resin. (8) Breaks through the thermoplastic synthetic resin compound coating (ill) and flows into the last concave part α from the tissue gap of the textile fabric 0 [with a low implant density, resulting in a stolen design (3)
An outsole (2) is formed. Since the thermoplastic resin compound forming the outsole (2) flows into the last concave part from the gap in the textile fabric a, even if the pattern on the bottom of the last (4) is finely formed, the thermoplastic resin compound forming the outsole (2) ) does not impede the fluidity of the thermoplastic resin compound that forms the last, so it is possible to form a stealth design that accurately corresponds to the shape of the last and to make it possible to attach it to the last smoothly. Therefore, injection molded shoes that are lightweight and have excellent cushioning properties can be obtained.

The following are effective as the injection molten thermoplastic resin blend and thermoplastic synthetic resin blend coating that form the outsole in this example. That is, when the ylP IJ vinyl chloride compound is used as the injection molten thermoplastic resin compound, the thermoplastic synthetic resin compound coating has an i? I
J Vinyl chloride type, polyurethane type, polyester type, polyff[vinyl type, polyvinylidene chloride type, etc. are effective. When a polyurethane compound is used as the injection molten thermoplastic resin compound, polyvinyl chloride, polyurethane, polyester, polyvinylidene chloride, etc. are effective as the thermoplastic synthetic resin compound coating. When SBR type is used as the injection molten thermoplastic resin compound, SBR type etc. are effective as the thermoplastic synthetic resin compound coating.

Figure 9 shows the last (4) and side moldings in another embodiment of the present invention in which the insole is formed of a knitted fabric reinforced by impregnating a thermoplastic synthetic resin compound.
A front sectional view of C13) with the cover (6) and midsole (8) attached is shown, and FIG. 10 is a partially enlarged view of the main bottom of FIG. 9. (2) is an outsole made of a thermoplastic resin for injection molded shoes, and (8) is an insole made by impregnating and reinforcing a knitted fabric with a low fiber density with a thermoplastic synthetic resin compound. The thermoplastic synthetic resin compound may be a natural resin such as natural rubber or a synthetic resin as long as it has an adhesive effect between threads, but water-soluble resins such as polyvinyl alcohol and polyvinyl acetate are preferable. As the knitted fabric, knitted fabric, especially net, is preferable. Nets have the disadvantage that they tend to stretch in any direction and the network structure is easily deformed by tension.
By impregnating and reinforcing the material with a thermoplastic synthetic resin compound, elongation and deformation in any direction can be adjusted, and the characteristic of not easily fraying from the cut edges can be maintained. When using a net as a knitting fabric, the number of weft and warp yarns in the network structure of the net is 3 to 50 yarns/1n each.
ch is preferred. Number of weft or warp threads is 3 / 1n
If it is less than ch, the degree of deformation of the net becomes very large and it becomes difficult to suppress the deformation even if it is impregnated with a thermoplastic synthetic resin compound. Then, there will be a part where the mesh connection part is missing at the cut edge, so
Sewing with the last (4) becomes insufficient, making it difficult to lock the sleeve (6) to the last (4). As is clear from Fig. 9, the sewing of the collar cover (6) and the inner sole (8) is done by sewing the outside of the collar cover (6) and the inner sole (8), and then sewing the collar cover (6) and the inner sole (8) together. Bottom (8)
The local edge (9) of the sewn part faces inward of the injection molded shoe (11, and the sewn part (6) and the insole 18) are made of a reverse California stitch sewn in a bag-like manner. End (9)
is injection molded and can be locked to the periphery of the last (4) which has a protrusion (5) for forming a sneaky design on the shoe. Therefore, in this embodiment, the local edge (9) of the sewing part (6) and the inner sole (8) is locked to the periphery of the last (4) having the convex part (5) forming a stealth design. Then, attach the shoe cover (6) with the insole (8) sewn on, and insert the injection molded shoe (1).
)'113. yg)
Mumo five Y (13)”' Q sealed, void (14)
When the thermoplastic resin compound that forms the outsole is injected into the inner sole (8), it flows into the last recess (+51) through the mesh of the knitted fabric with a low fiber density (0) forming the inner sole (8), and has a stolen design (3). Forms the outsole.

When constructed in this way, the thermoplastic resin compound forming the outsole (2) flows into the zero last recesses through the gaps in the textile fabric OI, so the pattern on the bottom of the last (4) is finely formed. However, the fluidity of the thermoplastic resin compound forming the outsole (2) is not inhibited, so a design that accurately corresponds to the last shape is formed.

Therefore, this invention does not have the advantages of a reverse California lace, so the lace cover and the insole can be attached smoothly at the end.
It is possible to prevent deformation, and it does not require any effort to attach unlike string strings.

Furthermore, as shown in the embodiments of the present invention, when using an insole with a lower fiber density than the insole to form a design, wearability and deformation are particularly poor compared to manufacturing methods other than the present invention. This makes a significant difference in prevention. In such a case, the effect of preventing deformation will be further improved if it is used in combination with reinforcement of a knitted or woven fabric having a low fiber density (as shown in the examples of the present invention).

Example 1 A textile fabric and a thermoplastic synthetic resin compound coating were manufactured using the following materials.

(1) Knitted and woven fabric Cheesecloth Vinylon single yarn (single yarn), both warp and weft, each consisting of 15 yarns/1 nch.

(2) Thermoplastic synthetic resin blend coating 0, 15 m thick vinyl chloride film Example 2 The following materials were used as the knitted fabric and thermoplastic synthetic resin blend coating.

(11m woven fabric made of single yarn (single yarn) with 68 warp threads/1 nch and 47 weft threads/1 nch).

(2) Thermoplastic synthetic resin compound coating 0.05 ttrm
Thick vinyl chloride film.

[Brief explanation of the drawing]

1 to 4 are conventional examples, and FIGS. 5 to 10 are illustrations of embodiments of the present invention. (1)...Injection molded shoes, (2)...Outsole, (3)...
・・Stealing design, (4) ・・Last, (5) ・・Convex part, (6) ・・・String, (force・・string, (8) ・・・Insole, (9) ...Sewn part local edge, 0 [...knitted fabric, (
1υ...thermoplastic synthetic resin coating, θ'3...side mold 1, (+3)...zetom mold, (l...
・Gap, (151...Last concave portion Patent applicant: Achilles Co., Ltd. Representative Patent Attorney Tadashi Yasuhara 2 Masayoshi Yasuhara 9- Figure 8 Figure 10

Claims (1)

[Claims] The peripheral edge of the reverse California lace, which is formed into a bag shape with the periphery edge of the clasp cover and insole facing inward, is locked to the bottom periphery lower than the convex part of the last, which has a convex part on the bottom surface that forms a stealth design. Then, attach the cover to the last, seal the lower part of the cover and the middle sole with the last, side mold, and set mold R, and then attach the cover to the last, side mold, and yl? A method for manufacturing injection molded shoes, which comprises forming an outsole by injecting a thermoplastic resin compound into the void formed by Tommol.