JPH045901A - Manufacture of shoe having multicolor sole having theft - Google Patents

Abstract

PURPOSE:To sufficiently make the shoe light in weight without using a foam resin, and also, to increase strength, flexibility against a warp and a cushion ability by molding an out-sole having many theft holes, and executing injection molding of an inner sole or a mid-sole of its upper side under a specific condition. CONSTITUTION:A middle sole 3 and instep leather 4 are hung into a last mold 7, an out-sole 1 having theft holes of 3-10mm diameter is placed on a bottom mold 6, and by setting said both molds 6, 7, the left and the right side molds 8 and a toe mold 9 by press-contacting, an inner solve void 20 is formed, a sole resin material of 2000 - 4000cp (200 deg.C) viscosity is injected from a runner by 190 - 300kg/cm<2> pressure and at 180 - 200 deg.C temperature, and simultaneously with molding of an inner sole 2, the middle sole 3 and the instep leather 4 are unified and finished to a shoe of a double layer sole. By combination of said various conditions, injection and filling of a resin material into the sole void can be executed without allowing it to intrude into theft holes 5 on the upper face of the out-sole 1, many cavities are formed on the sole, the shoe is light in weight and strength of the sole is held moderately, and flexibility against a warp and the cushionability are also increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing shoes with two- or three-color soles (two- or three-layer soles) by injection molding in two or three stages. .

(Prior Art) Conventionally, shoes with soles of two or three colors generally have
It is manufactured by molding a two- or three-layer sole by injection of sole material in two or three stages and simultaneously integrating it with the midsole and shoelace.

(Problem to be solved by the invention) However, although conventional shoes with two- or three-color soles have excellent design effects, they tend to have thick soles because of their multilayer structure. The entire bottom tends to be very heavy,
Therefore, it was necessary to reduce the weight of the sole. Light weight is an essential proposition for providing shoes that are less tiring to wear.

Furthermore, if each layer of a two-layer or three-layer sole is entirely made of resin material (non-foamed), the flexibility and cushioning properties of the shoe will be significantly degraded due to the increased rigidity of the sole as a whole. Therefore, conventionally, the entire or part of the shoe sole, especially the outsole, has generally been constructed from a foamed resin material.

On the other hand, in order to reduce the weight of shoes with such two-color soles, a method has been proposed in the past in which a gap is provided in the sole at the center 1.

However, with this method, when conventional injection molding technology is applied, the sole material of the foamed resin often penetrates into the gaps, so it is difficult to achieve a satisfactory weight reduction of the sole. I couldn't come.

On the other hand, if a foamed resin with a fairly high foaming rate is used as the sole material, it may be possible to achieve a sufficiently satisfactory reduction, but on the other hand, the strength and rigidity of the sole will be significantly reduced. , resulting in a shoe product that does not have the required shoe quality. Therefore, there is a certain limit to reducing the weight by adjusting the foaming rate or the type of foamed resin.

Light weight, strength, flexibility against warping, cushioning, etc. are all directly related to comfort and are important factors to consider in the design of shoes and products.

The present invention has been made in consideration of a series of circumstances, and its purpose is to achieve sufficient weight reduction without the necessity of using foamed resin materials, and to provide strength, flexibility against warping, and cushioning. To provide a method for manufacturing shoes with multi-colored soles, which can stably and reliably manufacture shoes with two- or three-color soles that are good in terms of physical and mechanical properties.

(Means for Solving the Problems) The inventor of the present invention, Nagisa, has conducted extensive research into methods for manufacturing shoes with two- or three-color soles by multi-step injection molding, and has found that the method of manufacturing shoes with two- or three-color soles has been found to be suitable for injection molding of outsoles. A large number of holes with a diameter of 3 to 10 mm are formed on the upper surface of the sole, preferably regularly.Next, the molded outsole is incorporated, and the sole above it is injection molded under certain conditions. According to 2. OnO~4.0[]0c
A sole resin material having a viscosity of
By injection molding the sole under conditions of 300 kg/cm2 and a temperature of 180 to 200°C, it is completely unexpected that the injected sole resin material does not penetrate into the holes on the top surface of the outsole, reducing the weight of the sole. The present invention has been completed based on the discovery that the weight is significantly lighter.

Therefore, the method for manufacturing shoes with multi-colored soles according to the present invention can produce shoes with two- or three-color soles in two or three colors.
In the manufacturing method by step injection molding, a large number of holes with a diameter of 3 to 10111111 are formed in the sole-I.
- mold the outsole to be formed on the surface, then 2,0
00-4. A sole resin material having a viscosity of ODD cp (200°C) is applied to the sole molding gap on the upper surface of the outsole at a pressure of 190 to 300 kg/cm2 and a temperature of 1.
It is characterized in that the sole above the outsole is molded by injection molding under conditions of 80 to 20 [1'C].

(Summary of the invention) That is, the method for manufacturing shoes according to the present invention provides two-color or three-color shoes.
In the manufacturing process of shoes with colored soles, an outsole with a large number of holes is molded, and the upper inner sole (in the case of two-color soles) or the -mid sole (in the case of three-color soles) is formed. This is a method of injection molding under specific conditions.

Therefore, the present invention can be applied to a method of manufacturing shoes with two- or three-color soles by two- or three-step injection molding, for example, a conventional general manufacturing method by two- or three-step injection molding. It is.

In the present invention, a large number of stealth holes are formed on the upper surface of the outsole, preferably arranged regularly. The number of stealth holes is not limited or may be suitably 10 to 50, for example. Further, the position where the hole is formed may be formed only at the heel, only at the non-stepping part, or only at the toe, and is not limited in any way.

The shape of the hole is not particularly limited; it may be a round hole for boat fishing, or a square hole, and the size of the hole may be 3 to 10 mm in diameter.
The dimensions are required to be within the range of . If the holes have dimensions in this range, the sole resin material will not be released during injection under the following conditions, and weight reduction can be achieved. but,
If the diameter of the hole exceeds 10 mm, the sole resin material may enter during injection. - If the diameter of the hole is less than 3 mm, it will be difficult to mold an outsole with such a hole, and it will not be possible to achieve sufficient weight reduction.

The shape, method, number, and placement of the holes are not only important for weight reduction, but also are factors that determine various characteristics and performance, such as the strength of the sole, flexibility against warping, and cushioning properties of the shoe. Therefore, design decisions should be made taking into account the criteria to be used for these characteristics and performance.

In addition, in the present invention, the material used for the sole (inner sole or midsole) on the upper side of the outsole is 2,000 yen.
The sole resin material needs to have a viscosity of 0 to 4,000 cp (200°C). If the viscosity is within this range, the sole resin material will not enter the hole, and the resin material can be smoothly injected. However, resin materials with a low viscosity of less than 2,000 cp (200°C) may cause the material to enter the hole, whereas resin materials with a high viscosity of more than 4,00 cp (200°C) The resin material makes it difficult to inject and fill the sole void.

Furthermore, in the present invention, injection molding for molding the upper side of the outsole is performed by applying the resin material to a pressure of 1! to
~300kg#: It is necessary to inject into the sole cavity under conditions of m2 and temperature of 180 to 200°C. If the conditions are within this range, the sole resin material will not enter the hole, and the resin material can be smoothly injected. However, if the above conditions are outside the range, the resin material may enter the void, or it may become difficult to inject and fill the sole void with the resin material.

(Operation) According to the method of the present invention, by the combination of these conditions,
It is possible to inject and fill the sole void with the sole resin material without intruding into the hole in the upper surface of the outsole. Therefore, a large number of air-filled cavities are formed in the sole, and the weight of the sole is reduced. In addition, the strength of the sole is maintained within an appropriate range, and the flexibility and cushioning effects against warping are significantly increased.

(Example) An embodiment of the present invention will be described below.

This example relates to the manufacture of shoes with two-color soles by two-step injection molding. As shown in FIG. 1, first, the insole 3 and the sleeve 4 are suspended in the last mold 7, and then the separately injection-molded outsole 1 is placed on the bottom mold 6. The inner sole gap 20 is formed by press-setting the mold 7, the left and right site molds 8.8, and the toe molds 9,
Subsequently, an inner sole resin material having a viscosity of 2,000 cp (200° C.) was applied from the runner 16 to the inner sole molding cavity 20 at a pressure of 200 kg/cm2 and a temperature of 20° C.
The inner sole 2 is molded by injection and filling under the condition of 0° C., and is simultaneously integrated with the midsole 3 and the shoelace 4, thereby producing a shoe with a two-layer sole.

As shown in FIG. 2, the outsole 1 used for such injection molding has a large number of holes 5 each having a diameter of 3 mm formed regularly on the upper surface 10 of the sole at intervals of 1 mm.

As shown in FIG. 3, this outsole l uses a mold 11 having a mold surface 15 corresponding to the outsole upper surface 10, and presses the mold 11, the bottom mold toro and other molds 12 into the solder 1. to form an outsole gap 13, and then fill the gap 13 by injecting outsole resin material from a runner 14 to form a large number of holes 5 on the sole top surface 10. Prefabricated by a molding process.

The resulting shoes with two-color soles are approximately 20% cheaper than conventional shoes.
It is lighter and more flexible against warping,
Furthermore, properties such as strength and cushioning properties were also good.

(Effects of the Invention) As described above, the shoe manufacturing method according to the present invention suppresses the intrusion of sole material into the holes and leaves the holes as they are, thereby eliminating air-filled holes. By forming a large number of them in the sole of the shoe, the weight of the differentiated sole is reduced, resulting in a shoe that is sufficiently lightweight, has increased flexibility against warping, and has increased strength and cooking resistance. This has the effect that it is possible to stably and reliably manufacture shoes with two- or three-color soles in which properties such as properties are well maintained.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the injection molding process according to the method of the embodiment of the present invention in manufacturing shoes with two-color soles. FIG. 2 is a plan view showing the top surface of the outsole of the shoe shown in FIG. 1), and FIG. 3 is a sectional view showing the manufacturing process of the outsole shown in FIG. 1. In the diagram, 1...Outsole 2...Innersole 3...
Insole 4...Piece 5...Tear hole 6...Bottom mold 7...
・Last mold 8...Side mold 9...Toe mold 10...Outsole top surface 11...Innersole bottom surface 13...Outsole void

Claims (1)

[Claims] A method for manufacturing shoes with two- or three-color soles by two- or three-step injection molding. First, an outsole is molded in which a large number of holes with a diameter of 3 to 10 mm are formed on the upper surface of the sole. Next, a sole resin material having a viscosity of 2,000 to 4,000 cp (200°C) is applied to the sole molding cavity in contact with the upper surface of the outsole at a pressure of 190 to 300 kg/cm^.
2. A method for manufacturing shoes with multi-colored soles having a thin layer, characterized by molding the upper sole of the outsole by injection molding at a temperature of 180 to 200°C.