KR890000902B1 - A midsole - Google Patents

Abstract

The midsole with 2 layers of polymer form at least has almost the same configuration with a main sole. The inner layer, esp. formed by polyurethane, has a hardness of 20-60 and the outer layer has a hardness of 25-80 to make the outer layer harder than the inner one.

Description

Midsoul

1A is a plan view of a first embodiment of the present invention.

Figure 1b is a longitudinal cross-sectional view thereof.

2A and 2B are a plan view and a longitudinal sectional view of the same variant.

3A and 3B are plan and side views of the same alternative variant.

4A and 4B are a plan view and a longitudinal sectional view of the second embodiment.

5A and 5B are a plan view and a side view of a third embodiment.

* Explanation of symbols for main parts of the drawings

1: inner layer foam 2: outer layer foam

3: protrusion 4: curved part

5: Line part 6: Upper layer part

7: lower layer 8: horseshoe type

9: line of the heel

The present invention relates to a midsole (midsole) capable of increasing running functionality and improving moldability. In recent years, in order to alleviate the impact on the foot when driving on roads, concrete, pavement, etc., shoe soles are replaced with sponge soles, and thick sponge soles are used for shoes depending on the function. In these soles, the main window is a solid or abrasion resistant sponge window, in which a sponge layer with a good cushioning level of water layer between the main window and the upper is usually inserted. . This midsole requires a certain amount of rigidity, has a considerable thickness, and requires a flexing force that can withstand the repelling force of the cushion layer itself at the tread. There was an extra load on the leg, which caused fatigue of the foot, and the wearing feeling of the shoe was damaged. In addition, the midsoul is formed by laminating different layers of different colors, and especially in the case where a sponge layer having a low hardness and good cushioning properties is laminated in order to reduce weight, the outer wall surface of the layer is exposed as it is, so as to be compressed. In addition, the fatigue was so intense that the cushioning property was significantly reduced in a short time, so that the wearability, that is, the wearer's feeling, was impaired, and the shape retention was low.

In view of such a phenomenon, the present invention combines the outer foam of polyester-based urethane with the elastic inner foam, thereby providing excellent properties in the breaking strength of the outer foam of polyester-based urethane and the low compressive permanent distortion. The object of the present invention is to provide a midsole (middle sole) having good shape retention and moldability and excellent running functionality by effectively exhibiting the advantages of cushioning and lightness of the inner layer foam having goodness and elasticity.

The present invention consists of at least two polymer foam guns laminated between the main window and the upper, wherein the polymer foam layer has a contour almost similar to the main window, and the elastic inner layer foam is the outer layer of the polyester-based urethane. It is covered by a foam.

As described above, the midsole of the present invention uses a combination of materials that vary the hardness of the outer foam of the polyester-based urethane and the elastic inner foam, so that the hardness difference gradually varies between the parts. The hardness of the outer foam is in the range of 25 to 80 degrees, and the hardness of the inner foam is in the range of 20 to 60 degrees, as expressed by the Asuka durometer type c (hereinafter equal to), and the average specific gravity of the inner foam is 0.05 to 0.30, the average of the outer foam Specific gravity is used in the range of 0.20 to 0.60. Selective combinations from the members in this range can reduce the hardness of appropriate portions such as the tread portion and the center portion, thereby making it possible to reduce the weight.

This midsole is layered between the main window and the upper, and its lower surface is formed to follow the upper contour of the main window, and the upper surface is modeled after the upper contour of the upper. Examples of the material of the inner foam include polyolefin resins such as polyethylene and ethylene / vinyl acetate copolymer (EVA), foams of rubber, and mixtures thereof. The polyester-based urethane foam of outer layer foam is diisocyanate, such as 4, 4- diphenylmethane isocyanate and 4-4 'dicyclo hexyl methadiisocyanate, glycol, such as ethylene glycol, 1, 4- hexanediol, adipate-type polyethylene. It is a urethane foam obtained by making polyesterdiol, such as an adipate, a poly (1, 4- butylene adipate), and a poly (1, 6- hexane adipate), react.

Next, embodiments of the present invention will be described with reference to the drawings.

In Fig. 1a, which is a plan view of the midsole of the first embodiment, and in Fig. 1b, which is a longitudinal cross-sectional view, 1 is an inner foam, and the inner foam is almost similar to the contour of the shoe's insole, and the thickness of the front part is thin and the thickness of the rear part is It is thickly formed. The entire surface of the inner layer foam 1 is covered with the outer layer foam 2 to obtain an optimal shape midsole. The inner foam 1 in this case is a foamed EVA (polyethylene, ethylene-vinylacetate copolymer) having an asuka hardness of 30 degrees and an average specific gravity of 0,07 to 0.1, and the outer foam 2 has a hardness of 50 degrees and an average specific gravity of 0.3 to 0.4. Polyester foamed polyurethane is used. The inner foam 1 is cut from the foamed EVA plate and combined bonded to yield the thickness of the back.

Also, as shown in Figs. 2A and 2B, the foamed EVA board is divided into two parts back and forth between the front part 5 and the heel side part, and the heel part side is divided into two layers of the upper part part 6 and the lower part part 7 again. You may join together. In this case, the hardness of each part should be used in combination differently. The Yaskawa hardness is, for example, 20 degrees at the top 5, 35 degrees at the upper 6 of the heel, and 45 degrees at the lower 7. In addition, the structure of the heel portion, as shown in Fig. 3a, constitutes the horseshoe-shaped portion 8 as the member having the highest hardness at the rear portion of the heel portion 9, and the inner shell side of the horseshoe-shaped portion 8. You may make it 8a protrude to the claw line side position rather than the outer shell side 8b. In this way, when the landing pressure moves from the outer shell side to the inner shell side, the ankle portion is excessively rotated on the inner shell side due to the pressure applied to the inner shell side, thereby preventing damage to the ankle and the like. The structure of these inner layer foams 1 can also be applied to the following second and third embodiments. The inner foam 1 is obtained by cutting the non-foamed EVA composition into a predetermined shape, pressing heating in a mold, and integrally molding simultaneously with foaming. The inner foam 1 is held approximately in the center by appropriate means in a forming space corresponding to the shape of the midsoul formed between the upper mold and the lower mold in combination. In addition, a liquid polyurethane material that becomes the outer layer foam 2 is injected into the molding space and subjected to a foam hardening reaction to form a mid soul, which is a polymer foam in which the inner layer foam 1 is coated and adhered to the outer layer foam 2. If the contour of the inner layer foam 1 is changed as needed, the contour side of the outer layer foam 2 can be freely changed in accordance with this contour.

4A and 4B show a second embodiment of the present invention, which is a plan view and a longitudinal sectional view, respectively. In this embodiment, the inner foam 1 is a foamed EVA having a hardness of 35 degrees and an average specific gravity of 0.1 to 0.15. As the outer foaming agent 2, a foamed polyurethane of a polyester crab having a hardness of 50 degrees and an average specific gravity of 0.3 to 0.4 is used. As in the first embodiment, the inner layer foam 1 is almost entirely covered by the outer layer foam 2. However, the outer layer foam 2 on the upper surface of the front part is excluded, and the inner layer foam 1 is directly exposed to the surface at the removed portion.

In the present embodiment, the liquid polyurethane to be the outer foam 2 in the molding space formed by combining the upper mold and the lower mold while keeping the exposed upper surface of the inner foam 1 in contact with the upper mold inner surface, is formed by combining the upper mold and the lower mold. The material is injected into the foam curing reaction to form a mid soul, which is a polymer foam.

5 and 5a show a third embodiment of the present invention, which is a plan view and a longitudinal sectional view, respectively. In this embodiment, the foamed EVA having a hardness of 35 degrees and an average specific gravity of 0.1 to 0.15 is used for the inner foam 1, and the polyester foamed polyurethane having a hardness of 55 degrees and an average specific gravity of 0.4 to 0.5 is used for the outer foam 2. As in the first embodiment, the inner foam 1 is covered with the outer foam 2.

In this embodiment, several protrusions 3 are provided on both sides of the tread portion of the inner layer foam 1 and on the outer shell side of the heel portion, and the outer shell side cross-section of the protrusion 3 coincides with the contour section of the outer foam 2. It is formed to. Moreover, the curved part 4 of the concave shape is provided toward the center from the inner shell side of the heel part of the inner layer foam 1 toward the center, and the contour width of the outer layer foam 2 is adjusted in accordance with the curved part 4. Make it larger than other contour width. In addition, an appropriate number of protrusions 3 provided on both sides of the tread portion of the inner foam 1 and on the outer shell side of the heel portion are further extended, and the extension portions of the protrusions 3 are formed on the upper mold and the release mold during the formation of the midsoul. The foamed curing reaction is carried out by injecting a liquid polyurethane material in which the outer layer blowing agent (2) turns around while being inserted into a hole in the mold inner surface communicating with the forming space formed by the mold combination of the mold combination, and then extending the protrusions (3). The part is excised along the contour section of the midsoul, so that the polymer foam layer exhibited on the contour section is formed by the mid-soul.

Also in this embodiment, the outer foam (2) on the upper part of the front part including the protrusion (3) and the upper part of the heel (3) on the heel is excluded, and the inner foam (1) is exposed to the occupational surface according to this removal part. It may be formed to. The color tone of this protrusion part 3 may be matched with the color tone of the inner foam 1, and only the protrusion part 3 or its outer end surface may be colored by red, blue, yellow or the like color. Moreover, the outer cross-sectional shape of this protrusion part 3 can take the shape of an enemy, such as a circle, a triangle, and a ridge, according to the function.

As described above, in the midsoul of Example 1, the entire surface of the inner layer foam 1 made of foamed EVA almost similar to the sole is covered and bonded with the outer layer foam 2 made of polyester-based foamed polyurethane. The defects such as low breaking strength and damage caused by slight external force, and defects such as recesses in thick parts such as heel, which makes it difficult to reduce the weight of polyester-based polyurethane, especially low-foamed polyurethane, are eliminated. The combination of cushioning and light weight combined with high strength and low breakdown strength and good recovery ability combined with polyester foamed polyurethane can be effectively exhibited. In addition, when the thickness of the tread portion of the outer layer foam 2 is made thin, the flexibility can be increased, and the bending resistance to the foot of the shoe wearer can be alleviated.

Even if the thickness of the heel portion of the inner layer foam 1 is close, the outer layer foam 2 having a high hardness is covered and coated by the inner layer foam 1, so that the effect is light, rich in cushioning properties, and low side shake. Moreover, in the heel part, since the thin layer of the outer layer foam 2 coats the circumference of the thick heel portion of the inner layer foam 1, it is rich in crumbness without generating a dent and reduces the impact at the time of landing. There is an absorbable effect. Since the inner foam 1 is covered by the outer foam 2 having a hardness higher than that, the hardness on the upper surface thereof becomes lower from the outer contour toward the center and the hardness gradually changes so that the step of the shoe wearer's foot is increased. It is possible to remarkably improve the wearing feeling of shoes without having any unpleasant feelings such as (段 蹉). In addition, according to the modification of the present embodiment, since the mid-soul is divided and bonded to the inner foam of each part to obtain a material and hardness suitable for each part, each of the parts including the outer foam by appropriately selecting the optimum hardness and material in each part. The difference in hardness between the parts can be given more smoothly, and by utilizing the fashion of another material, it is possible to improve the wearing feeling of shoes and to improve the cushioning property and the running functionality.

In the second embodiment, the midsoul acts on the toe part by mainly compressing and elongating the foamed EVA on the upper face of the inner layer foam 1 being exposed directly to the top part of the foot in addition to the effect of the first embodiment. Absorption of the stretching force (력 力) to reduce the stretching resistance of the shoe wearer's foot has the effect of reducing fatigue.

趾球)쪽으로 나아가고 착지가 종료한 후는 주로 모지구의 제2, 제3지의 발가락으로 지면을 차고 앞쪽으로 진행하므로, 상기한 바와같이 외층 발포체(2)의 뒷꿈치 외갑측 단부를 외층 발포체(2)보다도 경도가 낮은 내층 발포체(1)의 돌부(3)와 치환함으로써 먼지 뒷꿈치 중앙으로부터 착지가 시작되면 뒷꿈치와 외갑측의 돌부(3)가 답부압에 의하여 압축이 되므로, 답부의 이동을 뒷꿈치 중앙으로부터 뒷꿈치와 외갑측에 따라서 이동시키는 길 안내인의 작용을 하며, 다시 외층 발포체(2)의 뒷꿈치 내갑측으로부터 흙밟지 않는부에 걸쳐서의 내갑측 단부와 윤곽폭을 다른 부분의 윤곽폭보다도 넓힘으로써, 답부의 이동을 확실하게, 보다 쿠션성이 있는 뒷꿈치의 외갑측에 따라서 선부에로 이동시킬 수 있음으로써, 답부의 이동이 반대로 뒷꿈치의 내갑측에 따라서 선방으로 이동할 때 생기는 발목 등의 손상을 회피할 수가 있다. 더우기 답부부의 양측 단면 및 뒷꿈치 외갑측 단면에 내층 발포체(1)의 돌부(3)가 나타나 있고, 이 돌부(3)는 소망하는 색이며 또한 적의 형상으로 형성할 수 있으므로, 강렬한 악센트로되어 미관을 향상시키며 좋은 인상을 줄 수가 있다.In the third embodiment, the mid soul can further enhance the running functionality of the mid soul in the first embodiment. A moderate number of inner layer foams 1 made of foamed EVA having a lower hardness than outer layer foams 2 made of polyester-based foamed polyurethane, as described above, in the most intensely extending part of the midsoul and its outer ends. By providing the protrusions 3, the protrusions 3 of the foamed EVA can be easily compressed and elongated to relieve and absorb the flexing force when the treads are stretched, thereby reducing the stretch resistance to the foot of the shoe wearer, thereby reducing fatigue. In addition, landing starts almost from the center of the heel, and the movement of the thigh is carried from the small earth to the mother earth along the outer shell side.

After the landing is completed and the landing is completed, the front of the second and third fingers of the mother earth is driven forward to the front, so that the heel outer shell side end of the outer foam 2 is covered with the outer foam 2 as described above. When landing starts from the center of the dust heel by substituting with the protrusion 3 of the inner layer foam 1 having a lower hardness, the protrusion 3 on the heel and the outer shell side is compressed by the pressure of the foot. By acting as a road guide to move along the heel and outer shell side, the inner shell side end portion and the contour width from the inner heel side of the outer layer foam 2 to the non-tread portion are wider than the contour width of other portions, The movement of the foot can be reliably moved along the ridge along the outer shell side of the cushioned heel, so that the movement of the foot is reversed along the inner shell side of the heel. When standing move to save, it is possible to avoid damage to the ankle, etc. may occur. Moreover, the protrusions 3 of the inner foam 1 are shown on both side cross sections of the tread and the heel outer shell side cross sections, and the protrusions 3 have a desired color and can be formed into an enemy shape, resulting in a strong accent and aesthetic appearance. It can make a good impression.

The midsoul of the present invention is composed of at least two layers of polymer foam layers mounted between the shoe sole and the upper of the shoe so that the polymer foam layer has a contour almost similar to the original sole, and the elastic inner foam is higher than the inner foam. Since it is coated with the outer layer foam of polyester urethane of hardness, it has the advantage of excellent cushioning and lightness of inner layer foam, excellent property of breaking strength of outer layer foam, low compression set and good resilience. The combined effect is exerted and the synergistic effect is exerted, and it is possible to adjust the thickness and shape of each part layer of the outer part of the bent part and the heel part or the shape of each part to adjust the structure to a predetermined structure, thereby providing flexibility, cushioning properties and running. Enhancement of driving functions such as stability, landing shock mitigation, and prevention of civil war It can be achieved.

Claims (5)

It consists of at least two layers of polymer foam sandwiched between the main window and the upper, all of these polymer foam layers have a contour almost similar to the main window, and the elastic inner foam is formed on the outer foam of polyester-based urethane. The inner foam is 20 to 60 degrees in the Asuka durometer C type, the outer foam is 25 to 80 degrees in the C type, and the hardness of the outer foam is higher than the hardness of the inner foam. The mid soul characterized by. The mid soul according to claim 1, wherein the inner foam is formed by a plurality of divided joints, and a material and hardness suitable for each part are selected. The mid soul according to claim 1 or 3, wherein the upper surface of the corresponding portion of the outer portion of the outer foam is cut out to expose the inner foam layer of the only portion of the outer portion. 4. The midsoul according to claim 1 or 3, wherein cutouts are provided on both sides of the upper portion of the outer layer foam and / or on the outer shell side of the heel portion, and the cutout portion is filled by the inner layer foam. The mid sole according to claim 1 or 3, wherein the mid-sole is formed in such a manner that the contour width is increased from the inner side of the heel to the outer foam so as not to be stepped on, and the inner layer is foamed.

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