Double-color double-density shoe sole and forming process thereof

Abstract

The invention discloses a double-color dual-density shoe sole which comprises a shoe sole body, the shoe sole body is provided with a first shoe sole layer and a second shoe sole layer which are different in color, the first shoe sole layer and the second shoe sole layer are supercritical TPU foaming shoe soles, the first shoe sole layer is located above the second shoe sole layer, and the double-color dual-density shoe sole further comprises a partition plate capable of being heated and melted. The partition plate is located between the first sole layer and the second sole layer, the size of the partition plate is matched with the lower bottom face of the first sole layer and the upper surface of the second sole layer, the hardness of the first sole layer is smaller than that of the second sole layer, and the difference value between the hardness of the first sole layer and the hardness of the second sole layer is 3-10 A. The partition plate, the first sole layer and the second sole layer are integrally formed through physical foaming; compared with the prior art, the double-color and double-density shoe sole is formed through one-time physical foaming, the first-color popcorn shoe sole and the second-color popcorn shoe sole do not need to be formed respectively, the boundary fusion degree between the first-color popcorn shoe sole and the second-color popcorn shoe sole is high, and there is no boundary between the first-color popcorn shoe sole and the second-color popcorn shoe sole.

Description

Technical Field

[0001] The invention relates to the field of double-layer sole molding, in particular to a double-color double-density sole and a molding process thereof. Background Art

[0002] The first and second layers of the double-layer sole are different in color or density, which can improve the taste of the entire shoe and improve the shock absorption performance. The existing double-layer soles are disclosed in the application number 2018204278556. A kind of upper and lower double-layer ETPU sole, which includes a first ETPU layer and a second ETPU layer formed by steam heating in a foaming mold in sequence, the first ETPU layer is foamed and formed by the first ETPU particles, and the second ETPU layer is foamed and formed by the second ETPU particles. The first ETPU particles and the second ETPU particles are different in color and / or density. In the actual molding process of the above-mentioned double-layer sole, the first layer of the sole is generally molded in the first molding mold first, and the first layer of the sole is taken out after the molding, and then the molded first layer of the sole is placed in the second molding mold in advance, and then the second ETPU particles are put in, and then steam is passed into the second molding mold, and finally the double-layer sole is molded.

[0003] However, the above-mentioned molding method causes the first ETPU layer and the second ETPU layer to be molded separately using a molding mold, and the second ETPU layer is connected after the first ETPU layer is completely molded. This results in a clear dividing line between the first ETPU layer and the second ETPU layer without a grainy feeling, and also causes the first ETPU layer and the second ETPU layer to have a weak degree of fusion at the junction, which seriously affects the quality and performance of the product.

[0004] In view of this, the inventor of this case conducted an in-depth study on the problem, which resulted in this case. Summary of the invention

[0005] The purpose of the present invention is to provide a double-color double-density sole and a molding process thereof, so as to solve the problem that the boundary fusion degree between the existing double-layer soles is poor and affects the product quality.

[0006] In order to achieve the purpose, the present invention adopts such technical solution:

[0007] A two-color and two-density sole and a molding process thereof, comprising a sole body, wherein the sole body comprises a first sole layer and a second sole layer of different colors, wherein the first sole layer and the second sole layer are both supercritical TPU foamed soles, wherein the first sole layer is located above the second sole layer, and further comprising a heat-meltable partition plate, wherein the partition plate is located between the first sole layer and the second sole layer, wherein the size of the partition plate matches the lower bottom surface of the first sole layer and the upper surface of the second sole layer, wherein the hardness of the first sole layer is less than that of the second sole layer, and the hardness difference between the first sole layer and the second sole layer is 3-10A, and the partition plate, the first sole layer and the second sole layer are integrally physically foamed and molded.

[0008] The partition plate is a hot melt adhesive film.

[0009] The partition plate is a TPU plate or a nylon plate.

[0010] The thickness of the partition plate is 2-5 mm.

[0011] The double-color double-density sole of the present invention is formed by physical foaming in one piece. Heat is generated during the foaming process so that the partition plate is melted between the first sole layer and the second sole layer by heat, so that there is no dividing line between the first sole layer and the second sole layer, and the fusion degree at the junction of the first sole layer and the second sole layer is enhanced, so that the outer side of the sole body is smooth. In addition, the hardness of the first sole layer is less than that of the second sole layer, and the density difference between the first sole layer and the second sole layer needs to be controlled, and the first sole layer and the second sole layer have different colors, so that the first sole layer and the second sole layer are formed by physical foaming in one piece to form a double-color double-density sole, and the upper part of the entire sole body is softer during use, thereby improving the shock absorption effect and being comfortable to wear.

[0012] A molding process for a two-color and two-density sole comprises the following steps:

[0013] Step 1: prepare a forming mold having a concave mold and a convex mold, wherein the upper surface of the concave mold has a mold cavity, and the lower bottom surface of the convex mold has a mold core, and a forming mold cavity for sole foaming is formed when the concave mold and the convex mold are combined, and a plurality of support columns arranged at intervals are arranged in the mold cavity of the concave mold, and the top surface of the support columns is lower than the top surface of the concave mold;

[0014] Step 2: placing a partition plate, in step 1, a partition plate capable of being heated and melted is placed in the mold cavity of the concave mold, and the partition plate and the mold cavity of the concave film are closely matched to form an upper chamber and a lower chamber which are not connected to each other;

[0015] Step three: physical foaming molding, injecting the first supercritical TPU beads from the top surface of the punch into the space above the partition plate of the molding cavity, and injecting the second supercritical TPU beads into the lower cavity from the bottom surface of the die, the first supercritical TPU beads and the second supercritical TPU beads have different colors, and the density of the first supercritical TPU beads is less than the density of the second supercritical TPU beads; steam heating and pressurizing the molding mold while injecting the material, the partition plate of the first supercritical TPU beads and the second supercritical TPU beads melts as the temperature rises during the physical foaming process, and finally forming a two-color and double-density sole with a first color popcorn sole and a second color popcorn sole, and there is no dividing line between the first color popcorn sole and the second color popcorn sole, and the hardness difference between the first color popcorn sole and the second color popcorn sole is 3-10A.

[0016] The partition plate is a hot melt adhesive film.

[0017] The partition plate is a TPU plate or a nylon plate.

[0018] The thickness of the partition plate is 2-5 mm.

[0019] In the molding process of the double-color double-density sole of the present invention, when the first supercritical TPU beads and the second supercritical TPU beads are injected into the molding mold, foaming is performed while the lower part of the upper injection space and the upper part of the lower chamber are foamed first, and the partition plate is still in a fixed state. During the foaming process, the supercritical TPU beads continuously absorb heat, resulting in a gradual increase in the temperature in the molding mold. After the upper part of the upper injection space and the lower part of the lower chamber are foamed, the temperature in the molding mold reaches a temperature at which the partition plate can melt. The partition plate melts, for example, the melting point of the partition plate is 60 degrees, and the upper injection space is filled with foam. After the upper part of the spacer and the lower part of the lower chamber are foamed, the temperature in the molding mold reaches 60 degrees, and the partition plate melts (a partition plate with different melting points can be used as needed), and the first color popcorn sole and the second color popcorn sole are instantly released, so that the partition plate melts at the junction of the first color popcorn sole and the second color popcorn sole, and the junction of the first sole layer and the second sole layer is integrated, so that the double-color double-density sole formed by the first color popcorn sole and the second color popcorn sole has no dividing line, and finally a double-color double-density sole without a dividing line is formed, thereby improving the quality and performance of the product. Compared with the prior art, the sole formed by the molding process of the double-color double-density sole adopts one-time physical foaming molding, and there is no need to mold the first color popcorn sole and the second color popcorn sole separately, so that the junction between the first color popcorn sole and the second color popcorn sole is more fused and has no dividing line, thereby improving the quality and performance of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1It is a schematic structural diagram of the concave mold of the present invention.

[0021] Figure 2 This is a layered diagram in the molding cavity when the partition plate is not melted during the foaming process of the present invention. DETAILED DESCRIPTION

[0022] In order to further explain the technical solution of the present invention, it is described in detail below with reference to the accompanying drawings.

[0023] A two-color and two-density sole and its forming process, such as Figure 1-Figure 2 As shown, it includes a sole body, the sole body has a first sole layer and a second sole layer of different colors and a partition plate that can be heated and melted, the first sole layer and the second sole layer are both supercritical TPU foamed soles, the first sole layer is above the second sole layer, the partition plate is a hot melt adhesive film, and can also be a TPU plate or a nylon plate, the thickness of the partition plate is 2-5mm, the partition plate is between the first sole layer and the second sole layer, the size of the partition plate is consistent with the lower bottom surface of the first sole layer and the upper surface of the second sole layer, the hardness of the first sole layer is less than that of the second sole layer, and the hardness difference between the first sole layer and the second sole layer is 3-10A, and the partition plate, the first sole layer and the second sole layer are physically foamed as a whole.

[0024] The double-color double-density sole of the present invention is formed by physical foaming in one piece. Heat is generated during the foaming process so that the partition plate is melted between the first sole layer and the second sole layer by heat, so that there is no dividing line between the first sole layer and the second sole layer, and the fusion degree at the junction of the first sole layer and the second sole layer is enhanced, so that the outer side of the sole body is smooth. In addition, the hardness of the first sole layer is less than that of the second sole layer, and the density difference between the first sole layer and the second sole layer needs to be controlled, and the first sole layer and the second sole layer have different colors, so that the first sole layer and the second sole layer are formed by physical foaming in one piece to form a double-color double-density sole, and the upper part of the entire sole body is softer during use, thereby improving the shock absorption effect and being comfortable to wear.

[0025] A molding process for a double-color and double-density sole, characterized in that it comprises the following steps:

[0026] Step 1: prepare a molding die having a die concave mold 1 and a punch (not shown in the figure), the upper surface of the die concave mold 1 having a mold cavity, the lower bottom surface of the punch having a mold core, and a molding cavity for sole foaming molding is formed when the die concave mold 1 and the punch are molded together, and a plurality of spaced support columns 2 are provided in the mold cavity of the die concave mold 1, the top surface of the support columns 2 is lower than the top surface of the die concave mold 1, and when the die concave mold 1 and the punch are molded together, an upper injection space is provided between the lower bottom surface of the punch and the top surface of the support columns 2; in the present invention, it is preferred that a plurality of movable openings are provided at the bottom of the mold cavity of the die concave mold 1, the support columns 2 are movably sleeved within the range of the movable openings, and a moving plate (not shown in the figure) is provided below the die concave mold 1, the lower end of each support column 2 is connected to the top surface of the moving plate, and a driving cylinder for driving the moving plate to move out of the mold cavity or extend into the mold cavity is provided outside the bottom surface of the moving plate;

[0027] Step 2: placing the partition plate 3. A partition plate 3 capable of being heated and melted is placed in the mold cavity of the concave mold 1 in step 1. The partition plate 3 is a hot melt adhesive film, or a TPU plate or a nylon plate. A partition plate 3 with different melting points can be used as needed. The thickness of the partition plate is 2-5 mm. The outer wall of the partition plate 3 is tightly matched with the inner wall of the mold cavity of the concave film to form an upper chamber and a lower chamber that are not connected to each other.

[0028] Step 3: Physical foaming molding, injecting the first supercritical TPU beads 4 from the top surface of the male mold into the upper injection space of the molding cavity, and injecting the second supercritical TPU beads 5 from the bottom surface of the female mold 1 into the lower cavity. The first supercritical TPU beads 4 are injected from the male mold and the second supercritical TPU beads 5 are injected from the female mold 1. The existing method of injecting supercritical TPU beads into the molding mold is adopted, and no further details are given here. The first supercritical TPU beads 4 and the second supercritical TPU beads 5 have different colors, and the density of the first supercritical TPU beads 4 is less than the density of the second supercritical TPU beads 5, that is, the first supercritical TPU beads 4 have a smaller density than the second supercritical TPU beads 5 in the same unit volume. The number of supercritical TPU beads 4 is less than the number of second supercritical TPU beads 5 in the same unit volume; the molding mold is steam heated and pressurized while injecting the material, and the partition plate 3 of the first supercritical TPU beads 4 and the second supercritical TPU beads 5 melts as the temperature rises during the physical foaming process, and finally cooled to form a two-color and double-density sole with a first color popcorn sole and a second color popcorn sole. The hardness of the first color popcorn sole is less than that of the second color popcorn sole, and there is no dividing line between the first color popcorn sole and the second color popcorn sole, and the hardness difference between the first color popcorn sole and the second color popcorn sole is 3-10A.

[0029] A molding process of a double-color double-density sole of the present invention is adopted. When the first supercritical TPU beads 4 and the second supercritical TPU beads 5 are injected into the molding mold, foaming is performed while the injection is performed. The lower part of the upper injection space and the upper part of the lower chamber are foamed first. At this time, the partition plate 3 is still in a fixed state. During the foaming process, the supercritical TPU beads continuously absorb heat, resulting in a gradual increase in the temperature in the molding mold. After the upper part of the upper injection space and the lower part of the lower chamber are foamed, the temperature in the molding mold reaches a temperature at which the partition plate 3 can melt. The partition plate 3 melts. For example, the melting point of the partition plate 3 is 60 degrees. After the upper part of the upper injection space and the lower part of the lower chamber are foamed, the temperature in the molding mold reaches 60 degrees and the partition plate 3 melts. The first color popcorn sole and the second color popcorn sole are instantly released, so that the partition plate 3 is melted at the junction of the first color popcorn sole and the second color popcorn sole, and the first shoe The junction of the bottom layer and the second bottom layer is integrated, so that the double-color and double-density sole formed by the first color popcorn sole and the second color popcorn sole has no dividing line, and finally a double-color and double-density sole without a dividing line is formed, thereby improving the quality and performance of the product; after the foaming is completed and before the sole is completely cooled and formed, the driving cylinder is started to drive the support column 2 to move out of the forming mold and seal the movable opening, and the second supercritical TPU beads 5 will be released, so that the entire second color popcorn sole blocks the space where the support column 2 is not moved out of the forming mold, so that the bottom surface of the processed sole will not have a groove; compared with the prior art, the sole formed by the molding process of the double-color and double-density sole adopts one-time physical foaming molding, and there is no need to mold the first color popcorn sole and the second color popcorn sole separately, so that the junction between the first color popcorn sole and the second color popcorn sole is more integrated and has no dividing line, thereby improving the quality and performance of the product.

[0030] The product form of the present invention is not limited to the illustrations and embodiments of this case. Any appropriate changes or modifications made by anyone with similar ideas should be deemed to be within the patent scope of the present invention.

Claims

1. A two-color and two-density sole, comprising a sole body, wherein the sole body has a first sole layer and a second sole layer of different colors, wherein the first sole layer and the second sole layer are both supercritical TPU foamed soles, and the first sole layer is located above the second sole layer, characterized in that: It also includes a partition plate that can be heated and melted, the partition plate is located between the first bottom shoe layer and the second bottom shoe layer, the size of the partition plate is consistent with the lower bottom surface of the first bottom shoe layer and the upper surface of the second bottom shoe layer, the hardness of the first bottom shoe layer is less than the hardness of the second bottom shoe layer, and the hardness difference between the first bottom shoe layer and the second bottom shoe layer is 3-10A, and the partition plate, the first bottom shoe layer and the second bottom shoe layer are physically foamed and formed as a whole.

2. The dual-color dual-density sole according to claim 1, characterized in that: The partition plate is a hot melt adhesive film.

3. The dual-color dual-density sole according to claim 1, characterized in that: The partition plate is a TPU plate or a nylon plate.

4. The dual-color dual-density sole according to claim 1, characterized in that: The thickness of the partition plate is 2-5 mm.

5. A molding process for a two-color and two-density sole, characterized in that: The steps include: Step 1: prepare a forming mold having a concave mold and a convex mold, wherein the upper surface of the concave mold has a mold cavity, and the lower bottom surface of the convex mold has a mold core, and a forming mold cavity for sole foaming is formed when the concave mold and the convex mold are combined, and a plurality of support columns arranged at intervals are arranged in the mold cavity of the concave mold, and the top surface of the support columns is lower than the top surface of the concave mold; Step 2: placing a partition plate, in step 1, a partition plate capable of being heated and melted is placed in the mold cavity of the concave mold, and the partition plate and the mold cavity of the concave film are closely matched to form an upper chamber and a lower chamber which are not connected to each other; Step three: physical foaming molding, injecting the first supercritical TPU beads from the top surface of the punch into the space above the partition plate of the molding cavity, and injecting the second supercritical TPU beads into the lower cavity from the bottom surface of the die, the first supercritical TPU beads and the second supercritical TPU beads have different colors, and the density of the first supercritical TPU beads is less than the density of the second supercritical TPU beads; steam heating and pressurizing the molding mold while injecting the material, the partition plate of the first supercritical TPU beads and the second supercritical TPU beads melts as the temperature rises during the physical foaming process, and finally forming a two-color and double-density sole with a first color popcorn sole and a second color popcorn sole, and there is no dividing line between the first color popcorn sole and the second color popcorn sole, and the hardness difference between the first color popcorn sole and the second color popcorn sole is 3-10A.

6. The molding process of the double-color double-density sole according to claim 4, characterized in that: The partition plate is a hot melt adhesive film.

7. The molding process of the double-color double-density sole according to claim 4, characterized in that: The partition plate is a TPU plate or a nylon plate.

8. The molding process of the double-color double-density sole according to claim 4, characterized in that: The thickness of the partition plate is 2-5 mm.

Images