JPH056442B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing an injection molded shoe sole consisting of a multilayer partial sole.

[Conventional technology]

Conventionally, the general manufacturing method for injection molded shoe soles consisting of multi-layer partial soles is to first add a dummy last to the bottom mold to form the lower sole, which is the lower partial sole. are fitted to form a gap for forming the lower sole between these bottom molds and the dummy last for forming the lower sole, and then the lower sole is inserted into the gap for forming the lower sole. The lower sole is injection molded by injecting and filling the molding material, and then the dummy last for molding the lower sole is removed from the bottom mold, leaving the injection molded lower sole on the bottom mold. In addition, a dummy last for forming the upper sole, which is a partial sole of the upper side, is fitted into this bottom mold, and the dummy last for forming the lower sole and the upper sole is combined. An upper shoe sole molding cavity is formed between the upper shoe sole molding material and the upper shoe sole molding material is injected and filled into the upper shoe sole molding cavity to injection mold the upper shoe sole. It was clear.

[Problem that the invention seeks to solve]

By the way, in the conventional manufacturing method described above, when removing the dummy last for molding the lower sole while leaving the injection-molded lower sole on the bottom mold, the dummy last for molding the lower sole is removed. The side soles of the shoes adhered to each other, causing a phenomenon known as so-called "crying of the soles." For this reason, after molding the lower sole, the dummy last for molding the lower sole is replaced with the dummy last for molding the upper sole, and when the upper sole is injection molded on top of this lower sole. The upper shoe sole material of the upper shoe sole molding material flows into the gap between the separated lower shoe sole and the bottom mold, causing burrs that are protrusion of the shoe sole material, and burrs of the shoe sole material. A mixture of bleeding was occurring.

The present invention was made against the background of such problems in the prior art, and provides an injection molded shoe sole that can prevent the occurrence of burrs, which are the protrusion of the sole material, and bleeding, which is the mixture of the sole materials. The present invention provides a method for manufacturing.

[Means for solving problems]

That is, the present invention provides a method for manufacturing an injection molded shoe sole consisting of a multi-layer partial sole, in which a lower sole, which is a lower partial sole, is molded into a bottom mold. A dummy last for forming a side sole is fitted to form a gap for forming a lower sole between the bottom mold and the dummy last for forming a lower side sole. The lower sole is injected and filled with a lower sole molding material, and then the lower sole is injection molded, and the injection molded lower sole is left on the bottom mold for molding the lower sole. The dummy last is removed from the bottom mold, and then the dummy last for molding the upper sole, which is the partial sole of the upper part, is fitted into the bottom mold, and then A gap for forming an upper sole is formed between the dummy last for forming an upper sole, and the dummy last for forming an upper sole has a lower side remaining on the bottom mold at its bottom. A pressing protrusion is formed to directly press the upper surface of the sole, and then an upper sole molding material is injected and filled into the upper sole molding cavity to injection mold the upper sole. , there is provided a method for manufacturing an injection molded shoe sole, characterized in that at least one set of adjacent partial soles of the multi-layer partial soles are molded together.

[Effect]

Since the present invention is such a method, first, a dummy last for forming a lower sole is fitted into a bottom mold, and a dummy last for forming a lower sole is formed between the bottom mold and the dummy last for forming a lower sole. to form a space for use.

Thereafter, a lower sole molding material is injected and filled into the lower sole molding cavity to injection mold the lower sole.

Next, the dummy last for molding the lower sole is removed from the bottom mold, leaving the injection molded lower sole on the bottom mold.

Next, a dummy last for molding the upper sole is fitted onto the bottom mold on which the lower sole is placed, and the upper part is placed between the lower sole and the upper sole dummy last. A void for forming the sole of the shoe is formed.

At this time, the pressing protrusion formed on the bottom of the dummy last for forming the upper sole directly presses the upper surface of the lower sole remaining on the bottom mold toward the bottom mold. In this way, by pressing the upper surface of the lower sole with the pressing protrusion directly to the bottom mold side and fitting it, even if the lower sole is partially separated from the bottom mold, this peeled lower part A part of the sole can be pressed and fitted to the original placement position of the bottom mold.

Next, the upper sole layer molding material is injected and filled into the upper sole molding cavity to injection mold the upper sole.

By doing so, it is possible to prevent the occurrence of burrs, which are the protrusion of the sole material, and blemishes, which are the mixture of the sole materials.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on the drawings, but the present invention is not limited to these embodiments.

In addition, in describing this embodiment, a midsole protruding part in which a part of the midsole protrudes is disposed at least in the treading part and the heel part of the sole, and the tip surface of the midsole protruding part is approximately The surfaces of the sole are aligned and exposed on the contact surface of the shoe, and an outsole is formed by a first outsole and a second outsole, and a part of the second outsole is protruded from a predetermined position of the sole. An example of a method for manufacturing an injection molded sole for sports shoes in which a second outsole protrusion is installed, and the tip surface of the second outsole protrusion is exposed with the surface substantially aligned with the contact surface of the sole. Take it.

The method for manufacturing the injection molded shoe sole of the present invention will be explained in order from the bottom layer to the top layer. First, the first
As shown in FIGS. 1 and 2, the method for manufacturing the outsole A1 is to place a first outsole, which is the lower partial sole of the outsole A shown in FIGS. 3 and 4, on a bottom mold 10. The first dummy last (dummy last for forming the lower sole) 20 for molding the sole (lower sole) A1 is fitted to the bottom mold 10 and the first dummy last 20.
A first outsole molding cavity (lower sole molding cavity) 30 is formed between the two.

It should be noted that on this first dummy last 20, a side mold 40 and a main body last 50 to which a flap K is attached are stacked in order from the bottom.

Furthermore, a midsole protrusion forming annular protrusion 11 for forming a midsole protrusion M1 to be formed at the bottom of the midsole M, which will be described later, is formed in the stepping part and the heel part of the bottom mold 10.

Note that the forming part of the annular protrusion 11 for forming the midsole protrusion is formed on the bottom mold 1 after the sole is formed.
0, it becomes a protrusion movement gap U that promotes movement of the midsole protrusion M1 for the purpose of improving the slip resistance of the sole (see FIG. 4).

Furthermore, a second protrusion for molding a second outsole protrusion A21 formed at the bottom of the second outsole A2, which will be described later, is provided in the entire central part of the first dummy last 20 from the stepping part to the heel. An annular projection 21 for forming the portion is formed.

Annular projection 1 for molding these midsole projections
The protrusion length of the annular protrusion 21 for molding the first and second protrusions is such that the tip surface of the injection-molded midsole protrusion M1 and the tip surface of the second outsole protrusion A21 are approximately on the ground contact surface of the sole. This is the length that is exposed with the surfaces aligned.

After that, this first outsole molding cavity 3
A first outsole molding material (lower sole molding material) A11 is injected and filled into the bottom mold 10 from the first injection gate 12 formed in the bottom mold 10 to form the first outsole shown in FIGS. 3 and 4. A1 is injection molded.

Note that this first outsole molding material A11
is a hard shoe sole material with a hardness (Shore A) of 60 to 70 degrees after molding, and is made of, for example, polyvinyl chloride resin, a plasticizer, a stabilizer, and a red pigment. The mixing ratio of the first outsole molding material A11 is usually 100 parts by weight of polyvinyl chloride resin, 80 to 100 parts by weight of a plasticizer (dioctyl phthalate, dibutyl phthalate, etc.), and a stabilizer (tin-based mercaptan, barium zinc). etc.) 1~
3 parts by weight, and a red pigment (such as quinacridone)
It is 1 to 3 parts by weight.

Thereafter, the first dummy last 20 is removed from the bottom mold 10, leaving the injection-molded first outsole A1 on the bottom mold 10. By this removal, the annular protrusion 21 for forming the second protrusion is also removed, and a gap 60 for forming the second protrusion is formed in the gap where the annular protrusion 21 for forming the second protrusion is removed.

Note that this first dummy last 20 is removed by rotating the first dummy last 20 in the lateral direction.

Next, the second layer of the intermediate layer shown in FIGS.
The production of the outsole A2 involves molding a second outsole (upper sole) A2, which is the upper partial sole of the first outsole A1 shown in FIGS. 3 and 4, into the bottom mold 10. 2 dummy lasts (dummy lasts for forming upper soles) 70 are fitted to form a second outsole forming gap (upper sole forming gap) between these bottom molds 10 and the second dummy lasts 70. ) 80.

Furthermore, a pressing protrusion 90 is formed on the bottom portion 70a of the second dummy last 70 to directly press the upper surface A1a of the first outsole A1 remaining on the bottom mold 10.

This pressing projection 90 is composed of a large number of peripheral edge dividing pressing projections 91, 91, . . . that divide and press the peripheral edge of the first outsole A1.

The pressing protrusion 90 directly presses the upper surface A1a of the first outsole A1 remaining on the bottom mold 10 toward the bottom mold, and the bottom mold 10
By fitting the second dummy last 70 and the second dummy last 70, even if the first dummy last 20 is removed,
A part of the first outsole A1 is the bottom mold 1
Even if it has peeled off from 0, press this peeled part with the pressing protrusion 9.
Since it is pressed against the bottom mold 10 at 0, it is possible to prevent the occurrence of burrs, which are protrusion of the sole material, and bleeding, which is a mixture of the sole materials, when pouring the second outsole molding material A22, which will be described later.

The second dummy last 70 is fitted to the bottom mold 10 by first fitting the second dummy last 70 to the lower part of the side mold 40 on which the main body last 50 is placed, and then fitting the second dummy last 70 to the bottom mold 10. This is done by fitting the bottom mold 10 to the lower part of the last 70.

Thereafter, the second outsole molding material (upper sole molding material) A22 is injected and filled into the second outsole molding cavity 80 from the second injection gate 13 formed in the bottom mold 10, as shown in FIG. , FIG. 4, and FIG. 7 show the second outsole A2.
is injection molded.

In addition, when molding this second outsole A2,
By injecting the second outsole molding material A22 into the second protrusion molding cavity 60, the injection-molded shoe formed at the bottom of the second outsole A2 is improved in its anti-slip properties and in bending (pressing and bending during walking). A second outsole protrusion A21 is simultaneously molded to provide a good balance with the shoe's elasticity and recovery.

In addition, this second outsole molding material A22
is a hard sole material that is slightly softer than the first outsole molding material A11 and has a hardness (Shore A) of 60 to 70 degrees after molding, and the materials include, for example, polyvinyl chloride resin, plasticizer, and stabilizer. , and black pigment. The mixing ratio of these materials is usually
For 100 parts by weight of polyvinyl chloride resin, 80 to 100 parts by weight of a plasticizer (dioctyl phthalate, dibutyl phthalate, etc.), 1 to 3 parts by weight of a stabilizer (tin mercaptan, barium zinc, etc.), and a black pigment (cabobon (black, etc.) 1 to 2 parts by weight.

Next, the process moves on to manufacturing the midsole M, which is the uppermost layer of the sole shown in FIG. The side mold 40 on which the main body last 50 is placed is lowered and fitted into the bottom mold 10, and a midsole molding gap 100 is formed between the second dummy last 70, the side mold 40, and the main body last 50.

Note that when removing the second dummy last 70 from the bottom mold 10, the second dummy last 70
A peripheral division pressing protrusion 9 formed on the bottom 70a of the
The pressing protrusions 90 consisting of 1, 91, . By injecting the midsole molding material M2 and simultaneously molding the midsole intrusion part (not shown), the midsole intrusion part void 81 in which the midsole intrusion part is formed usually forms a part of the relatively heavy second outsole A2. Since it is a molded area, the weight of the injection molded shoe sole can be reduced.

Further, when the bottom mold 10 and the side mold 40 are fitted together, the annular protrusion 1 for forming the midsole protrusion formed on the bottom mold 10
At the same time, a midsole protrusion molding cavity 82 for molding a midsole protrusion M1 that adds anti-slip properties to the sole is also formed on the inner side of the protrusion 1.

Thereafter, the midsole molding material M2 is injected and filled into the midsole molding cavity 100 through the midsole injection gate 41 formed in the side mold 40 to injection mold the midsole M shown in FIGS. 3 and 4.

Note that the midsole protrusion M1 formed at the bottom of the midsole M
At the time of molding, the midsole molding material M2 is injected into the midsole protrusion molding cavity 100, thereby simultaneously molding.

In addition, this mid-sole molding material M2 is a soft sole material with a hardness (Shore A) of 50 to 60 degrees after molding, and specifically, it is a layer made of foamed polyvinyl chloride resin. By molding it with resin, it becomes the cushion part of the sole of the shoe.
Its materials include, for example, polyvinyl chloride resin, a blowing agent, a plasticizer, a stabilizer, and a white pigment, and the mixing ratio is usually 100 parts by weight of polyvinyl chloride resin to a blowing agent (azodicarbonamide). , benzenesulfonyl hydrazide, etc.)
1 to 3 parts by weight, plasticizer (dioctyl phthalate,
dibutyl phthalate, etc.) 90 to 110 parts by weight, stabilizers (tin-based mercaptan, barium zinc, etc.)
1.5 to 3 parts by weight, and 2 to 5 parts by weight of a white pigment (titanium oxide, etc.).

Thereafter, the molded product is removed from the bottom mold 10, side mold 40, and main body last 50 to manufacture a shoe having an injection molded sole.

Note that when removing the outsole from the bottom mold 10, the outsole A is removed from the annular projection 11 for forming the midsole projection formed in the bottom mold 10, and the outsole A is removed from the midsole projection forming annular projection 11 formed on the bottom mold 10 to improve the slip resistance of the sole. The protrusion movement gap U that promotes the movement of M1 is formed (see FIG. 4).

As explained above, in the method of manufacturing the injection molded shoe sole of the embodiment, the second dummy last 70
The first outsole A1 remaining on the bottom mold 10 by the pressing protrusion 90 formed on the bottom part 70a of
By pressing the upper surface A1a directly toward the bottom mold side and fitting the bottom mold 10 and the second dummy last 70, the first dummy last 2
Even if a part of the first outsole A1 is peeled off from the bottom mold 10 when removing the shoe, the peeled part is pressed against the bottom mold 10 by the pressing protrusion 90, so that burrs, which are protruding sole material, are removed. It is possible to prevent the occurrence of bleeding due to mixing of sole materials.

Further, in the embodiment, this pressing protrusion 90 is
The upper surface A of the first outsole A1 is composed of a large number of peripheral edge dividing pressing protrusions 91, 91, . . . that divide and press the peripheral edge of the outsole A1.
The entire part 1a can be pressed uniformly, and it is also possible to better prevent the occurrence of burrs and bleeding caused by mixing of the sole materials.

Further, in the embodiment, a relatively lightweight midsole intrusion portion (not shown) is molded in the molded area of the relatively heavy second outsole A2, thereby reducing the weight of the injection molded shoe sole.

Furthermore, in the embodiment, in such a method,
A midsole protruding part M in which a part of the midsole M protrudes at least from the treading part of the sole and the heel part.
1, and this midsole protrusion M1
The top surface of the first outsole A is exposed with its surface aligned with the contact surface of the sole of the shoe, and the outsole A is aligned with the first outsole A.
1 and a second outsole A2, and a second outsole protrusion A21 in which a part of the second outsole A2 protrudes is installed at a predetermined position on the sole, and this second outsole protrusion Part A21
By molding an injection-molded shoe sole in which the tip surface of the shoe is exposed with the tip surface almost aligned with the contact surface of the sole, shoes with improved slip resistance, flexibility, and design of the sole surface are manufactured. In some cases, it is possible to reduce the number of parts, reduce the number of work processes, and lower costs, and moreover, it is possible to achieve a higher level of functional diversity in shoes that have these effects. Alternatively, it is possible to manufacture injection molded shoes that can have more sophisticated designs added to the side surfaces as well.

Furthermore, in the embodiment, the first outsole A
Since the second outsole A2 is made slightly harder than the second outsole A2, the abrasion resistance of the injection molded shoe can be further improved.

Furthermore, in the embodiment, the second outsole A2 having a hardness intermediate between these soles M and A1 is interposed between the midsole M and the first outsole A1, so that the first outsole A1
The first outsole A1 has less change in hardness than when it is laminated directly onto the midsole M.
It is possible to manufacture injection molded shoe soles that are difficult to peel off.

Furthermore, in the embodiment, a second outsole protrusion A21 that is slightly harder than the midsole protrusion M1 is provided so as to cover the periphery of the midsole protrusion M1.
The protruding structure improves the anti-slip properties of injection molded shoes.
It is possible to manufacture an injection molded shoe sole that has a good balance with curvature (stretching and returning of a shoe that has been pushed and bent during walking).

Furthermore, in the embodiment, the midsole M, the first outsole A1, and the second outsole A
By making 2 different hues, it is possible to effectively add a more sophisticated design to the contact surface of the molded sole.

Furthermore, in the embodiment, since the protrusion floating gap U is formed around the midsole protrusion M1,
When the user walks, the midsole projection M1 is pushed and bent in the walking direction like a suction cup, making it possible to obtain a more effective anti-slip effect.

Although the embodiments of the present invention have been described above, the specific configuration and operation are not limited to these embodiments, and the present invention includes design changes within the scope of the invention. It will be done.

For example, in the embodiment, the dummy last for molding the upper sole is provided with a plurality of peripheral dividing pressing protrusions that divide and press the peripheral edge of the lower sole. A dummy last having pressing protrusions of other shapes formed at other positions may also be used.

In addition, in the embodiment, a midsole protruding part in which a part of the midsole made of a soft sole material projects is disposed at least at the treading part and the heel part of the sole,
In addition, the tip surface of the midsole protrusion is exposed so as to be flush with the contact surface of the sole, and the outsole made of a soft sole material is connected to the first outsole and the second outsole.
the first of these,
Injection for sports shoes in which the tip surfaces of a first outsole protrusion and a second outsole protrusion from which each part of the second outsole protrudes are substantially flush with the contact surface of the sole. Although the method for manufacturing a molded sole has been described, among the methods for manufacturing a sole consisting of multilayer partial soles, the method for manufacturing at least one pair of adjacent partial soles is the same as the lower sole according to the present invention. Any method may be used as long as it corresponds to the method of manufacturing the upper sole.

The order of molding the multilayer partial sole at this time is as described above, such as from the lower side, from the upper side, or by first molding a part of the upper side and then molding from the lower side. The method for manufacturing at least one set of adjacent partial soles is not limited as long as it corresponds to the method for manufacturing the lower sole and upper sole in the present invention.

〔Effect of the invention〕

According to the present invention, a dummy last for forming a lower sole, which is a partial sole of the lower side, is fitted into the bottom mold, and the bottom mold and the lower sole are molded together. A lower sole molding gap is formed between the dummy last and the lower sole molding material is injected and filled into the lower sole molding gap to injection mold the lower sole. ,
Next, the dummy last for molding the lower sole is removed from the bottom mold, leaving the injection molded lower sole on the bottom mold;
Next, a dummy last for molding the upper sole, which is a partial sole of the upper part, is fitted into the bottom mold, and a dummy last for molding the lower sole and the upper sole is fitted into the bottom mold. A gap for molding the upper sole is formed between the dummy last and the dummy last for molding the upper sole. The projection is formed, and then the upper sole molding material is injected and filled into the upper sole molding cavity to injection mold the upper sole, thereby forming the multilayer partial sole. Since at least one pair of adjacent partial soles are molded together, it is possible to prevent the occurrence of burrs, which are protrusion of the sole material, and bleeding, which is a mixture of the sole materials.

In addition, the dummy last for forming the upper sole is equipped with a plurality of peripheral dividing pressing protrusions that divide and press the peripheral edge of the lower sole. The entire upper surface can be pressed uniformly, and the occurrence of burrs and blemishes can be better prevented.

[Brief explanation of the drawing]

FIG. 1 is a central longitudinal cross-sectional view of a shoe sole molding die used in the lower sole manufacturing process according to the injection molded shoe manufacturing method according to the embodiment of the present invention, and FIG.
3 is a front view of an injection molded shoe manufactured by the injection molded shoe manufacturing method of the embodiment of the invention, and FIG. 4 is an injection molded shoe manufactured by the injection molded shoe manufacturing method of the embodiment. FIG. 5 is a central vertical sectional view of a shoe sole molding die used in the upper shoe sole manufacturing process according to the injection molded shoe manufacturing method according to the embodiment of the present invention, and FIG. 6 is a bottom view of FIG. - Cross-sectional view, 7th
The figure is a plan view of the sole molded by the sole molding die used in this upper sole manufacturing process, and FIG. 8 is another partial sole formed by the injection molded shoe manufacturing method according to the embodiment of the present invention. FIG. 2 is a central vertical cross-sectional view of a shoe sole molding die used in the manufacturing process of FIG. A...Outsole, A1...First outsole (lower sole), A2...Second outsole (upper sole), M...Mitsudosole, A11...
First outsole molding material (lower sole molding material), A1a...upper surface, A22... second outsole molding material (upper sole molding material), 10...
Bottom mold, 20...first dummy last (dummy last for forming the lower sole), 30... void for forming the first outsole (void for forming the lower sole),
70...Second dummy last (dummy last for molding the upper sole), 70a...bottom, 80...Gap for molding the second outsole (cavity for molding the upper sole),
90...pressing protrusion, 91, 91,...peripheral division pressing protrusion.

Claims (1)

[Claims] 1. In a method for manufacturing an injection molded shoe sole consisting of a multilayer partial sole, a lower side sole, which is a lower partial sole, is molded in a bottom mold. A dummy last for forming a lower sole is fitted to form a gap for forming a lower sole between the bottom mold and the dummy last for forming a lower sole; A lower sole molding material is injected and filled into the gap to injection mold the lower sole, and then the injection molded lower sole is left on the bottom mold to form the lower sole. Remove the dummy last from the bottom mold, and then fit the dummy last for molding the upper shoe sole, which is the partial sole of the upper part, into the bottom mold. An upper sole molding gap is formed between the sole and the upper sole molding dummy last, and the upper sole molding dummy last has a lower part remaining on the bottom mold at its bottom. A pressing protrusion is formed to directly press the upper surface of the side sole, and then an upper sole molding material is injected and filled into the upper sole molding cavity to injection mold the upper sole. A method for manufacturing an injection molded sole, characterized in that at least one set of adjacent partial soles of the plurality of multilayer partial soles are molded together. 2. The dummy last for molding the upper sole includes a dummy last having a plurality of peripheral dividing pressing protrusions that divide and press the peripheral edge of the lower sole. A method for producing an injection molded shoe sole as described in Section 1.