JPH0321201A - Method of manufacturing shoe having reinforced shell skin - Google Patents

Abstract

PURPOSE:To effectively prevent a shell skin from loosing its shape by temporarily applying a liner over a core, by temporarily attaching a shape holding fixture to a part of the liner while fastening dies, by press-casting synthetic resin in a heated molten condition into a mold cavity for the shell skin, and by auxiliary adjusting the shape of the shape holding fixture so as to make the liner into close contact with the synthetic resin in order to obtain a soft shell skin which is then parted from the dies. CONSTITUTION:A shape holding fixture 4 is formed from hard or semihard synthetic resin. A liner 2 is sewn to be formed in a foot shape, and thus sewn liner 2 is applied over a male component or foot shape core 3 of a shell skin forming dies. The shape holding fixture is temporarily attached to the outer surface of the liner 2 while the dies being fastened, and synthetic resin is press-cast into a shell skin forming cavity. The synthetic resin forming the shell skin is also press-cast into gaps among the female die, the shape holding fixture 4 and the liner 2. The synthetic resin press-cast in the forming cavity is auxiliary adjusted in its shape by adjusting the shape holding fixture 4, and is held in this adjusted shape so as to form the shell skin. A part of the shell skin 1 is held in the shape holding fixture 4 so that the shell skin 1 does not loose its shape even though the shoes are worn for a long time, and further, it is possible to mass-produce shoes each having a shell skin 1 which can stably hold a foot.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to improvements in shoes whose uppers are molded from synthetic resin, and more particularly to improvements in shoes whose uppers are partially reinforced with a member harder than the synthetic resin uppers.

[1. [Current technology and its problems] By molding part or all of the upper from a soft synthetic resin, a shoe with an ideal three-dimensionally curved upper can be manufactured. Shoes made using this method have features that cannot be achieved with shoes sewn from leather or cloth. In other words, shoes with this structure are not made by cutting a flat sheet material and molding it into a three-dimensional curved shape that follows the last of the foot, but by molding the upper into a three-dimensional curved shape from the beginning using a molding mold. As a result, they feel good on your feet from the moment you put them on, and provide a comfortable fit with minimal fatigue even when worn for long periods of time. Furthermore, this method does not require the time-consuming work of suspending the sheet-like upper material to the bottom, and has the advantage of being extremely easy to produce multiple products. Shoes whose uppers are molded from soft synthetic resin have an appearance similar to leather shoes, and provide the comfort of athletic shoes from the moment you put them on. This is because the upper can be made more flexible than in leather shoes, and the three-dimensional curved surface of the upper can be molded into an ideal shape. The more flexible the synthetic resin used to mold the upper, the more comfortable shoes can be manufactured that do not put pressure on the feet. However, the flexible synthetic resin upper cannot stably hold the foot on the sole. In other words, they are similar to slippers without a shell. In addition, the flexible upper skin has the disadvantage that it is easily deformed and loses its shape. Molding the carapace partially thicker improves stability and reduces deformation. However, shoes with thick insteps are not only heavy but also difficult to create a clean design. This drawback can be overcome by reinforcing a portion of the carapace with hard material. To achieve this, conventional leather shoes have a shape-retaining device called a counter in the heel area to reinforce this area. This is to prevent the heel from losing its shape. However, these shoes have the disadvantage that they are extremely time-consuming to manufacture. This is because the counter needs to be precisely molded to match the three-dimensional curved surface of the heel. If the three-dimensional curved shapes of the counter and the upper are different, the heel part of the shoe cannot be neatly finished. In particular, shoes that have a large counter and mold the upper,
It is extremely important to accurately match the entire counter to the three-dimensional curved surface of the upper. For example, women's bumps etc.
The area of the counter is large relative to the area of the upper, and the entire counter needs to be particularly precisely aligned with the shape of the upper. This is because the opening of the upper of pumps is extremely large and the area of the upper is small, and the upper of the shoes is required to have a stronger shape-retaining effect. In addition, in this type of shoe, flexible leather is often used for the upper, and distortion of the shape of the counter disturbs the overall shape of the upper, resulting in a significant deterioration in quality. In order to solve these drawbacks, the inventor of the present invention sought to develop a technique for hardening the counter at the same time as molding the upper (Japanese Patent Application No. 11-0237-1982). This technology is
A portion of the upper is reinforced with hot melt adhesive. In other words, on the carapace. A hot-melt adhesive is applied to the lining that adheres tightly, and this is heated and cured when the upper is molded. This method has the advantage that the counter is molded into a shape that follows the upper skin at the same time as the upper skin is molded, so that the counter can be precisely aligned with the upper skin. However, this method has the drawback of being limited by the counter's shape-retaining ability. For this reason, shoes that require particularly strong shape retention, for example,
Pumps for women and the like have the disadvantage that they do not have sufficient shape-retaining power and cannot provide comfortable wear and stability.

[Object of this invention]

This invention was developed with the aim of further solving this drawback, and an important object of this invention is to provide shoes with a reinforced upper that can extremely effectively prevent the upper from deforming over a long period of time. To provide a manufacturing method. Another important object of the present invention is to provide a shoe manufacturing method that allows a shape-retaining tool to be simply and easily aligned with the three-dimensional curved surface of the upper with great accuracy. Furthermore, another important object of the present invention is to assist in shaping the shape-retaining device with the molten heated synthetic resin used to mold the upper skin, and by adhering closely to the upper skin in the shaped state, the shape-retaining device can be shaped. To provide a manufacturing method for shoes that can accurately fit the upper leather by omitting the labor of crimping and shaping.

[Means to solve conventional problems]

In order to achieve the above-mentioned object, the method for manufacturing shoes with reinforced uppers of the present invention involves manufacturing shoes through the following steps. (a) Step of temporarily fixing the lining 2 to the core 3 with the upper molding mold open. (b) Temporarily fix the shape retention device 4 to a part of the lining 2. The shape retaining device 4 is a hard or semi-hard synthetic resin molded body,
Moreover, a molded body of a heat-softening synthetic resin is used, which becomes at least semi-softened when heated to the molten synthetic resin for molding the upper. (c) Clamp the mold and press the heated molten synthetic resin into the upper molding chamber. The shape retaining tool 4 is auxiliary shaped with the press-fitted synthetic resin in a heated and molten state, and the soft upper skin 1 is formed by closely adhering the lining. (d) The process includes the step of performing auxiliary shaping on the shape retaining device 4 and removing the mold by opening the mold and removing the upper skin 1 that has been molded in close contact with the lining 2.

[effect]

The shoe manufacturing method of the present invention has the advantage of being able to maintain the shape of a part of the upper in an ideal state, and yet being able to be mass-produced extremely easily and inexpensively. The reason for this is that the shape retaining tool 4 is auxiliary shaped with a synthetic resin in a heated and molten state that becomes the upper 1, and moreover, it is brought into close contact with the upper 1 in the auxiliary shaped state. The method for manufacturing shoes of the present invention that achieves this feature is preferably manufactured through the following steps. ■ The shape retaining device 4 is molded from a hard or semi-hard synthetic resin. ■ Sew lining 2 to the shape of the foot. (2) The sewn lining 2 is attached to the male die of the upper mold, that is, the core 3 of the foot shape. ■ Temporarily fix the shape retainer 4 on the surface of the lining 2. ■ After closing the mold, press the synthetic resin into the upper molding chamber. The synthetic resin for molding the upper is press-fitted between the female mold, the shape retaining device 4, and the lining 2. The synthetic resin pressed into the shaping room performs auxiliary shaping of the shape retaining tool 4, and also holds it in the shaped state to mold the upper skin 1. That is, the shape retainer 4, which is a heat-softening synthetic resin temporarily fixed in the shaping chamber, is heated by the molten synthetic resin press-fitted into the upper skin shaping chamber, and is softened or softened so as to be easily auxiliary shaped. Semi-softened. The molten synthetic resin is pressed into the shaping chamber under extremely high molding pressure. The ultra-high-pressure molten synthetic resin presses the entire surface of the shape-retaining tool 4, which has softened and become easier to shape, with high pressure, bringing the shape-retaining tool 4 into close contact with the three-dimensional curved surface of the core 3 surface. Perform auxiliary shaping along the lines. That is, the synthetic resin in the molten state that becomes the upper 1 is a. The shape retaining tool 4 is softened or semi-softened by heat to a state where auxiliary shaping is easy. b. The softened or semi-softened shape retainer 4 is molded into a core 3 under molding pressure.
auxiliary shaping by pressing on the surface. The action of a and b is the result of the synthetic resin molding the upper.
This is achieved by effectively utilizing heat and molding pressure. Therefore, even though the shape retaining tool 4 is auxiliary shaped into the three-dimensional curved surface of the upper 1, no special method is required for shaping it. The shape retaining tool 4 is auxiliary shaped into an ideal shape by simply temporarily fixing it in the carapace shaping chamber. Therefore, in the shoe manufacturing method of the present invention, the shape retaining device 4 is
Despite being able to be molded into a three-dimensional curved shape and tightly attached to the upper 1, it has the advantage that shoes can be mass-produced simply and easily at low cost. In addition to this, a notable feature of the present invention is that the auxiliary shaped shape retaining device can be closely attached to the upper skin without losing its shape in the shaped state. this is,
This is because the synthetic resin in a heated and molten state that becomes the upper is cooled and hardened to become the upper immediately after auxiliary shaping of the shape retainer. It is difficult to mold the shape retainer 4 and the upper 1 using separate molds and to accurately match their shapes three-dimensionally. Furthermore, if the shape retaining device 4 is to be adhered to the upper 1 while being maintained in the molded state, it is necessary to prevent the shape retaining device 4 from deforming after molding. However, in the shoe manufacturing method of the present invention, the shape-retaining device 4 is held in a shaped state and the upper 1 is molded, so the shape-retaining device 4 can be easily manufactured by extremely precisely matching the three-dimensional curved surface of the upper 1. There are features that can be used. That is, in the shoe manufacturing method of the present invention, even if the shape-retaining device 4 has a shape slightly different from the three-dimensional curved surface of the upper 1,
It has the advantage that the upper skin 1 and the shape retaining device 4 can be matched three-dimensionally. Therefore, the present invention has the advantage that a part of the upper 1 is kept in shape by the shape retainer 4, which prevents the shoe from losing its shape even when worn for a long time, and furthermore, the shoe can be mass-produced in which the upper 1 can stably hold the foot. be. In addition, since the shape-retaining device 4 is molded from a synthetic resin different from that of the upper 1, the shape-retaining device 4 can be made of a synthetic resin that has excellent shape-retaining properties that are required of the upper 1. The upper 1 can be made of synthetic resin, which is flexible and comfortable to wear. Usually, soft vinyl chloride or urethane is used for the upper 1 for comfort, and the shape retainer 4 is made of hard or semi-hard synthetic resin such as polyethylene, polypropylene, or nylon. .

[Preferred embodiment]

Embodiments of the present invention will be described below based on the drawings. However, the examples shown below are illustrative of a method for embodying the technical idea of the present invention, and the method of the present invention does not change the conditions of the manufacturing process, the materials used, or the shoes manufactured. It does not specify the structure etc. as shown below. This invention can be modified in various ways within the scope of the claims. Furthermore, in order to make the claims easier to understand, the numbers corresponding to the members shown in the embodiments are indicated in the "Claims column" and "Means for solving the conventional problems." Additional notes are added to the members shown in the "column" and "column of effects". However, the members described in the claims are by no means limited to the members shown in the examples. The shoe shown in FIG. 1 shows a shoe manufactured by the method of the present invention. In this shoe, the upper 1 is molded from synthetic resin. As shown in FIG. 2, a lining 2 and a shape-retaining device 4 are tightly attached to the inner surface of the upper l during molding of the upper. On the carapace l,
The midsole 8 is integrally molded. The upper l and the insole 8 are made of soft synthetic resin, such as soft polyvinyl chloride resin,
With polyurethane resin or a mixture of these,
It is molded into a three-dimensional curved shape that follows the surface of the foot. A grounding sole 5 is bonded to the lower surface of the midsole 8. Between the lining 2 and the upper l, located at the heel of the upper 1,
A shape retaining tool 4 having the shape shown in FIG. 3 is attached closely. Shape retention device 4
Using a mold different from the mold for molding the upper l, the upper l is molded into a shape that closely fits the heel part of the upper l. Shape retention device 4
The synthetic resin used to mold the upper is a heat-softening synthetic resin such as polyethylene, polypropylene, or nylon, so that it can be auxiliary shaped in a softened state by the synthetic resin used to mold the upper. Furthermore, it is also possible to mix fillers such as leather, fiber materials, powder, etc. into the synthetic resin used to mold the shape retaining device 4. Furthermore, the shape retainer 4 does not necessarily need to be injection molded. The shape retaining device 4 is molded from these synthetic resins into a shape that approximates the three-dimensional curved surface of the heel portion of the upper l before molding the upper. The shape retaining device 4 is auxiliary shaped by the upper skin molding synthetic resin and is brought into close contact with the inner surface of the upper skin 1. Therefore, the shape retaining device 4 is
It is not necessarily necessary to mold it exactly to the three-dimensional curved shape of the upper l. If necessary, one type of shape retainer 4 can be used as a shape retainer 4 for multiple types of shoe uppers 1 of different sizes and shapes. The shape of the shape retainer 4 is optimally designed depending on the position of the upper l and the type of shoe. When inserting the shape-retaining device 4 into the heel of women's pants, since the upper and lower widths of the upper 1 are narrow, the shape-retaining device 4 is
Increase the total length of. In the case of shoes with a wide top and bottom width, such as men's shoes, the overall length of the shape retaining device 4 is made somewhat shorter. Further, when the shape retaining device 4 is inserted into the toe portion of the instep l, auxiliary shaping is performed to the shape of the toe. The hardness of the shape retaining device 4 is adjusted to an optimum value depending on the place where it is inserted and the purpose of the shoe. The shape retainer 4 is made of a hard synthetic resin, and the thicker it is, the harder it becomes, and conversely, the softer the synthetic resin is used, and the thinner it is, the softer it becomes. Shape retention device 4
The thickness of the instep is determined by the shape retention and flexibility required for the instep.
The value is adjusted to the optimum value in consideration of the type of synthetic resin. Usually, the thickness of the shape retainer 4 is adjusted to a range of 0.2 to 2.5 mm. A specific example of the shape retaining device 4 used for the heel portion of women's pants is shown in FIGS. 4 and 5. The shape retaining device 4 shown in FIG.
A flange 6 is provided that is in close contact with the periphery of the midsole. The shape retaining tool 4 shown in these figures is partially provided with through holes 7. As shown in FIG. 4, the shape-retaining device 4 has a flange 6 on its lower edge.
When temporarily fastening to the core 3, the flange 6 can be temporarily fastened accurately in a fixed position along the bottom. Further, the shape retaining device 4 having this shape has the feature that the lower edge is reinforced by the collar 6, making it strong. Furthermore, as shown in FIG. 5, the one provided with the through hole 7 has the advantage of being able to firmly adhere to the upper 1 and the lining. This is because the upper molding synthetic resin enters the through hole 7. The shape retainer 4 is adhered to the lining 2 on the inner surface and to the upper l on the outer surface. To adhere the shape retaining device 4 to the lining 2, the shape retaining device 4 is adhered to the lining 2 with an adhesive. The shape retaining device 4 glued to the lining 2 is
It has the feature that it can be easily temporarily attached to the core 3 together with the lining 2. just,. The shape retainer 4 does not necessarily need to be adhered to the lining 2 and temporarily fixed to the core 3. For example, it is also possible to apply an adhesive that generates adhesive force when heated to the contact surface between the shape retaining tool 4 and the lining 2. This shape retainer 4 has a lining 2 and a core 3.
and temporarily fasten it on top of it. The shape retaining device 4 temporarily attached to the surface of the lining 2 is heated by heated synthetic resin pressed into the molding chamber, and the adhesive reacts and is bonded to the lining 2. As shown in FIG. 3, the shape-retaining device 4 inserted into the heel of the upper 1 is
A non-slip surface is provided on the contact surface with the lining 2, so that it can be easily temporarily fixed without adhering to the lining 2. This is because the non-slip surface makes it difficult to slip against the lining 2. In addition, the shape retaining device 4 has hook-shaped small protrusions on the surface, and the lining 2
It can also be temporarily attached to the surface. In this case, hook-shaped small protrusions are hooked onto the surface of the lining 2 for temporary fixation. Therefore, the lining 2 should be one on which the small hook-shaped protrusions can be caught. Furthermore, it is also possible to provide a locking protrusion 9 on the inner surface of the shape retainer. The locking protrusion 9 temporarily locks the shape retaining tool 4 at a certain distance from the core 3. That is, the tip of the locking protrusion 9 is
By pressing against the surface of the core 3, the shape retaining tool 4 is temporarily fixed at a certain distance from the core 3. The engaging protrusion 9 that presses the surface of the core 3 penetrates the lining 2 and comes into contact with the surface of the core 3. In the shoe manufacturing method of the present invention, it is not specified in which part of the upper l the shape retaining device 4 is inserted. As shown in FIG. 1, it can also be inserted into the heel, the toe, or other parts (not shown). As shown in Fig. 1, a shape retaining device 4 inserted into the toe part is ideal for correcting bunions.
Helps improve human health. The upper 1 shown in FIG. 2 has a shape-retaining device 4 in close contact with its inner surface, and a lining 2 in close contact with the inner surface of the shape-retaining device 4. However, this invention does not specify the state of close contact between the upper, the shape-retaining device, and the lining to the structure shown in this figure. As shown in FIG. 6, it is also possible to insert the upper l between the shape-retaining device 4 and the lining 2, and bring the shape-retaining device 4 and the lining 2 into close contact via the upper l. The lining 2 is sewn in a shape along the inner surface of the upper 1 so that it is attached to the core 3 in the mold-clamped state. The lining 2, which is entirely sewn in the shape of a foot, has the advantage that it can be easily temporarily fixed by simply attaching it to the core 3. For the lining 2, any sheet material having cushioning properties and breathability can be used. According to the inventor's experiments, a flexible urethane foam having open cells with fabric attached to both sides was most suitable. The urethane foam has a thickness of 1 to 4 mm, so that it has sufficient cushioning and moisture absorption properties.
5mm is used for the inner fabric that comes into contact with the foot.
A relatively thick and durable material should be used so that it will not tear even after long-term use, and a thin fabric made of thin fibers braided with a relatively coarse stitch is best for the fabric that will be in close contact with the upper 1. be. The lining 2, in which a cloth is adhered to the outer surface of the urethane foam, has a feature that the synthetic resin forming the upper 1 is prevented from entering into the cells of the urethane foam. The shoe shown in FIG. 1 is manufactured by temporarily fixing the lining 2 and shape retaining device 4 to the core 3 as shown in FIG. The resin is compressed and the instep 1 and the insole 8 are made.
The shape retaining tool 4 is integrally molded with a synthetic resin, and the shape retaining tool 4 is softened by the heat of the heated and molten synthetic resin, and auxiliary shaping is performed using molding pressure. After molding the upper, the mold is opened to remove the shape, a hem cloth is sewn along the opening, and the ground sole 5 is adhered to complete the shoe.

[Brief explanation of drawings]

Fig. 1 is a side view showing an example of a shoe manufactured by the method of the present invention, Fig. 2 is a sectional view showing a mold for forming the upper by applying a lining to the core, and Fig. 3 is a sectional view showing the lining. , FIG. 4 and FIG. 5 are perspective views showing specific examples of the shape retaining tool, and FIG. 6 is a cross-sectional view of a mold for molding an upper according to another embodiment. 1... Upper skin, 2... Lining,
3... core, 4... shape retainer, 5... grounded bottom, 6... tsuba,
7...Through hole, 8...Insole,
9...Latching protrusion. Figure 4 Procedural amendment (voluntary) 1. Case description 1999 Patent Application No. 1 55 1 35 2. Name of the invention Method for manufacturing shoes with reinforced uppers 3. Relationship with the case of the person making the amendment Patent applicant address: 2-3-3 Shinminami-Fukushima, Tokushima City, Tokushima Prefecture Name
Tatsuo Fukuoka 4. Agent 5. Date of amendment order Voluntary

Claims (1)

[Claims] A method for manufacturing shoes with reinforced uppers comprising the following steps. (a) Temporarily fixing the lining 2 to the core 3 with the upper mold mold open; (b) molding a part of the lining 2 with a hard or semi-hard synthetic resin, and Temporarily fixing the shape retaining device 4 made of a heat-softening synthetic resin that becomes at least semi-softened when heated to the molten upper molding synthetic resin; (c) Clamping the mold and molding the upper; A step of press-fitting a synthetic resin in a heated and molten state into the chamber, auxiliary shaping of the shape-retaining device 4 with the press-fitted synthetic resin in a heated and molten state, and molding a soft upper skin 1 by closely adhering the lining; ) Auxiliary shaping of the shape-retaining device 4,
It consists of a step of opening the mold and removing the upper 1 which has been molded in close contact with the lining 2.