JPS62155802A - Production of shoes reduced in weight - 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] Industrial Field of Application The present invention relates to a method for manufacturing lightweight shoes, and more particularly, holes and recesses (hereinafter referred to as "sneakers II") for reducing sole volume on the inner surface. The present invention relates to an improvement in a method for manufacturing shoes having a lightweight outsole using a hot air vulcanization method.

Conventional Technology In recent years, with the increasing popularity of leisure and sports, in order to meet the demand for lighter shoes, an important technical challenge in this industry has been to reduce the weight of the soles, which account for the majority of the weight of shoes. It's happening.

As a means of reducing the weight of outsole, it is commonly used to use a press-formed outsole (hereinafter referred to as ?! molded outsole rt) with many holes.

However, in the shoe making method using hot air vulcanization,
When using the outsole 1 provided with 11..., the unvulcanized inner sole 22' and center core 23' located above the outsole will be exposed to high temperatures of 130°C to 140°C in the vulcanizing can. When it is softened at the bottom, it is pushed into the hole 11 by the air pressure of about 3 KJ/ad inside the can, or it hangs down due to the weight of the inner bottom or inner core, and is vulcanized in that state. As shown in the figure, there is a problem in that the inner surface of the shoe becomes uneven, resulting in a defective product.

In order to solve this problem, in the past, a pre-vulcanized material was created and used as the midsole or core located above the outsole. According to this means, the insole and core do not soften even under high temperatures inside the vulcanizing can, so the above-mentioned drawback of the dents is eliminated.

However, if a (vulcanized) molded sole is used for the outsole, and already vulcanized materials are used for the insole and insole, not only will the material cost be high, but the outsole and insole, Since it is necessary to particularly carefully adhere the inner core and the shoe cover to each other, workability becomes poor. Also, during vulcanization in the can, the adhesive part tends to return, etc.
Quality defects such as deformation and poor adhesion are likely to occur.

In such cases, the original feature of the hot air vulcanization method is that the unvulcanized rubber parts are closely bonded and molded along the last with good workability, and then vulcanized all at once in the can to achieve a uniform shape. However, the advantage of being able to produce 8 rubber-soled shoes with excellent adhesive strength at a low cost was not fully utilized.

Problems to be Solved by the Invention The present invention uses a hot air vulcanization method to create shoes with a sole that is lightened by a stealth design! ! '! In doing so, we focused on the above-mentioned problems and tried to solve them, and at the same time, we aimed to obtain at low cost a shoe that is not only lightweight, but also has high adhesive strength, fits well on the foot, and has a well-proportioned shape.

Means for solving the problem Unvulcanized and unfoamed rubber sheets 1 to 21 containing a foaming agent
A midsole material 2 whose main opening element is a laminate of a slightly hard heat-resistant sheet 1-22 is suspended and molded around the periphery of the midsole material 2, with the slightly hard heat-resistant sheet facing outward. Attach the outsole 1 with holes 11.11... on the inner surface and make the shell body a.
This shoe manufacturing method is characterized by molding a rubber sheet, vulcanizing it with hot air, and foaming the unvulcanized and unfoamed rubber sheet 21 at the same time as the vulcanization.

2. A midsole cloth 24 is glued to the top layer of the midsole material 2. The insole cloth may be of general-purpose material. As the unvulcanized and unfoamed rubber sheet 21, a known co-foamed insole composition can be used. The thickness of the sheet is o, 3mm to 2. It can be selected appropriately within a range of about Omrrr. Preferably 0.5 m to i,
It's about omm. Adjust the foaming ratio to about 2 to 4 times.

The slightly hard heat-resistant sheet 22 has a temperature of 130°C to 150°C.
It requires properties that do not easily soften when heated for 60 to 100 minutes at a high temperature of °C, and commonly used fibrous boards such as fiberboard and hard fiberboard, or semi-rigid plastic boards with the same effect as these. You can choose from etc. Boards, which are commonly used for shoe making, are the most preferred material because they have good adhesion and shape retention during shoe molding. The thickness is 0.5m~2.
0M is appropriate.

The outsole 1 in the present invention is preferably made of a material that does not easily soften when heated at a high temperature of 130° C. to 150° C. for 60 minutes to 100 minutes and has good adhesive properties. A typical example is a mold bottom made of semi-vulcanized or vulcanized rubber. The outsole is designed to be lightweight by forming sufficient grooves 11, 11... at least on the side opposite to the ground contact surface. In addition to the anti-slip uneven pattern 12 on the ground surface, it is also free to provide anti-stealing unevenness.

The conditions for hot air vulcanization may be general conditions. - For example, temperature 130℃~150℃, can air pressure 2.089/
o4~3. OK! j/Cl71 vulcanization time is 40 minutes to 100 minutes.

Functions and Effects As a result of the above-described configuration, the present invention exhibits the following functions and effects.

1) Outsole 11.11... A slightly hard heat-resistant sheet is located on the upper side and provides support, so even though the unvulcanized rubber sheet 21 is used for the insole, the vulcanized Even if the rubber sheet 21 is softened in the sulfur can, it will not be press-fitted into the hole or sag, and a flat inner bottom surface can be obtained.

2) After the unvulcanized and unfoamed rubber sheet 21 containing a foaming agent is suspended and molded as an insole material, the sheet 21 is heated in a vulcanizing can, so that the sheet 21 foams and increases in volume. As a result, the looseness gap 5 that otherwise occurs between the mold 4 and the insole material 2 is eliminated, resulting in a well-proportioned shoe body that is faithful to the shape of the mold. It can be made into shoes.

In particular, in the case of the present invention, since the slightly hard seams 1 to 22 are used as the insole material, when hanging the cover, a slight loosening gap 5 is created along the mold, but this can be tightened and balanced. It can be a shoe with a broken shape.

3) Since the unvulcanized, unfoamed insole rubber foams when laminated with the slightly hard sheet 1~, the foaming direction is regulated by the hard sheet, so the foaming does not spread laterally.
The majority of the foam 211 is extremely uniform in the thickness direction,
No distortion or distortion occurs.

In this case, by laminating and adhering the insole cloth 24 on the upper layer of the insole material, the sheet 21 can be foamed in a sandwich-like manner, so that the above-mentioned effect can be perfected. If necessary, a general-purpose core 23 may be used.

In that case, even if the core is unvulcanized, the sheet 22
There is no need to worry about deformation as it is supported by

/I) 1 The shoes obtained according to the present invention are molded firmly and integrally using a hot air vulcanization method, so that the individual holes 11, 11... provided on the outsole 1 are bonded to the insole material 2. Together they form an air chamber 11'. The air chamber functions to absorb large shocks during employment, and the foam rubber sheet 21
1 gives an extremely good feel to the soles of the feet, and the slightly hard sheet 22, which constitutes the midsole material, increases walking stability.As a result of the combination of these effects, the resulting shoes are Not only is it lightweight, but it is also good for the feet, and the fins are extremely functional.

5) Since an unvulcanized and unfoamed rubber sheet is used, workability is good and adhesive strength is excellent, and costs can be reduced.

In addition, in the present invention, the main components of the insole material 2 are a rubber sheet 21 and a slightly hard heat-resistant sheet 22;
The sheets 21, 22 do not necessarily have to be provided over the entirety of the insole, but may be provided only on the heel, depending on the arrangement of the shoes, for example.

Furthermore, as long as the effects of the present invention are not impaired, it is free to provide not only the insole cloth 24 and the unvulcanized core material 23 but also other layers as the insole material 2 in advance.

In addition, the sole 1 used in the present invention is mainly intended for molded soles that are semi-vulcanized or vulcanized, but it is also applicable to so-called cold press molded soles that are obtained by pressing at a temperature that does not vulcanize the rubber. Applicable. In this case, the composition of the rubber fabric should be selected (one that is unlikely to soften due to heat) so that the rubber fabric itself does not undergo deformation such as expansion or contraction under high temperatures in a hot air vulcanizer, or Provide a means of communication to the inside of the shoe to prevent thieves from creating a sealed condition, or
It is necessary to take auxiliary measures, such as changing the angle at which the shoes are placed in the vulcanizing can, so that the sole rubber itself does not sag.

The material of the outsole 1 is not limited to rubber, but can be widely applied to thermoplastic rubber and other materials that have the same effect as vulcanized rubber.

Further, the outsole 1 may be a solid body or a porous body. A sole with a hole in the porous body is very preferable for weight reduction, but it is necessary to select one in which the porous body itself does not undergo deformation such as shrinkage deformation in the vulcanizing can. .

EXAMPLE An unvulcanized, unfoamed rubber sheet 21 with a thickness of 0.6 m and the following composition was prepared by a conventional method, and a cotton insole cloth 24 with a thickness of 0.3 m was pasted on one side. Kojin Ale (trademark of fiberboard made by Rinzai Co., Ltd.) 22 with a thickness of 0.7 is pasted together, and an unvulcanized core with a thickness of 0.5 is pasted on the bottom surface to form the midsole material 2. obtain. Add this to the bottom of mold 4.

・[Composition] Natural rubber / 16.0 parts sulfur
2.0 Accelerator 3.0! ! zinc oxide
2. OII softener 1.0
Ij filler 38. O〃 Hydrazine foaming agent 6. O〃Urea-based foaming aid 2.0〃An ordinary cover 3 made of a front and a back cover bonded together with rubber glue is suspended in the above-mentioned mold 4 by a conventional method, and is semi-vulcanized in a separate mold. bottom 1
(Black type sole rubber. Total weight: 150 g. Approximately 20 volume% of 11.11... is provided in 16 sections from the non-stepping part to the heel part. The thickness of the sole is 4 mm in the treading part. N heel Part 16
m. ) was adhered with rubber glue, and an external unvulcanized rubber tape was wrapped along the adhesive edge to reinforce the adhesion (not shown).

Then, it is placed in a hot air vulcanization can and the internal pressure is 3 K3/c.
#1: Hot air vulcanization was performed at a temperature of 130° C. for 60 minutes to obtain lighter shoes. A flat sponge layer 211 that was uniformly foamed and vulcanized was formed on the inner surface of this shoe, and its thickness including the inner sole fabric was about 2.0 ffiffi.

Furthermore, the shoes were very well-proportioned, and each part was completely integrated.

[Brief explanation of drawings]

Figures 1 to 3 show the main parts of an embodiment of the present invention. Figure 1 is a sectional view for explaining the state before vulcanization, Figure 2 is an enlarged view of the main parts, and Figure 3 is a cross-sectional view for explaining the state before vulcanization. The figure is an enlarged view showing the state after vulcanization, and FIG. 4 is an enlarged view showing the conventional problem. In the diagram 1... Outsole 11... Steal 12
... Bottom unevenness 2 ... Middle sole material 21.
... Unvulcanized, unfoamed rubber sheet 22 ... Slightly hard heat-resistant sheet 3 ... Cover 4 Metal 5 ... Loosening gap for hanging a ... Sheath bodies are shown respectively. one or more one

Claims (1)

[Claims] An insole material whose main component is a laminate of an unvulcanized and unfoamed rubber sheet containing a foaming agent and a slightly hard heat-resistant sheet is made with the slightly hard heat-resistant sheet on the outside, and the surrounding area is A shoe body is formed by suspending and molding a shoe cover, pasting an outsole with holes and recesses on the inner surface to reduce the sole volume, and then vulcanizing it in hot air to form an unvulcanized and A shoe manufacturing method characterized by foaming an unfoamed rubber sheet at the same time as vulcanization.