Forming mold of two-color foaming 3D printing shoe sole with ventilation function

Abstract

The invention relates to a bicolor foaming 3D printing shoe sole forming mold with a ventilation function, the mold comprises a bottom cover, a middle plate and an upper cover, a lower mold is arranged in the middle of the bottom cover, an aluminum mold is arranged in the middle of the middle plate, the lower mold comprises a shoe sole half sole area, a middle area and a shoe sole heel area, and the upper cover is arranged in the middle of the middle plate. The half sole area and the middle area of the sole are separated by a first partition piece; the middle area and the sole heel area are separated through a second partition piece. A plurality of first vertical columns are arranged in the half sole area of the sole; and a plurality of second vertical columns are arranged in the heel area of the sole.

Description

Technical Field

[0001] This invention relates to the field of shoe sole molding technology, specifically to a molding mold for a breathable two-color foamed 3D printed shoe sole. Background Technology

[0002] The style and comfort of shoes largely stem from the sole. Different sole materials and processes determine the aesthetics and comfort of a shoe. Traditional sole materials include rubber, polyurethane (PU), tendon, TPU, and various other materials. With the rise of the sports industry, the variety of sole materials has also increased, from conventional foam soles to various foam materials with different properties and standards, such as EVA foam, PU foam, and supercritical foam. More importantly, based on the increasingly mature foaming technology, a variety of foam sole series have been developed, including single-stage foaming, double-stage foaming, single-color foaming, and two-color foaming.

[0003] However, a major problem is that most foam soles on the market are currently two-tone foam soles. While two-tone foam soles are quite common, there hasn't been a emergence of new functional two-tone foam soles, such as those with breathable and waterproof features. Although some functional soles are available through post-installation bonding or adhesive methods, they are not truly one-piece molded two-tone foam breathable and waterproof soles. Because adhesive bonding and post-installation methods still carry the risk of sole detachment, this can lead to leaks and render the shoes unwearable. Summary of the Invention

[0004] The present invention aims to provide a molding mold for a breathable two-color foam 3D printed shoe sole. The technical problem to be solved includes at least how to develop a molding mold for a breathable two-color foam 3D printed shoe sole. Using this molding mold, a one-piece molded two-color foam shoe sole can be made without bonding. The shoe sole has built-in small holes and breathable function. After adding a waterproof and breathable membrane, the shoe sole has waterproof and breathable function.

[0005] To achieve the above objectives, the present invention provides a molding die for a breathable, two-color foamed 3D printed shoe sole, comprising a bottom cover, a mid-plate, and a top cover. A lower mold is disposed in the center of the bottom cover, and an aluminum mold is disposed in the center of the mid-plate. The lower mold includes a forefoot area, a mid-section area, and a heel area of ​​the sole. The forefoot area and the mid-section area are separated by a first dividing piece; the mid-section area and the heel area are separated by a second dividing piece. A plurality of first vertical columns are disposed in the forefoot area; and a plurality of second vertical columns are disposed in the heel area.

[0006] Preferably, when the bottom cover, middle plate, and top cover are stacked and assembled together from bottom to top, the aluminum mold is located directly above the lower mold.

[0007] Preferably, the diameter of the first vertical column and the second vertical column is less than or equal to 1 mm.

[0008] Preferably, the diameter of the first vertical column and the second vertical column is 0.2 mm to 0.8 mm.

[0009] Preferably, the height of the first vertical column and the second vertical column is less than or equal to 20 mm.

[0010] Preferably, the height of the first vertical column and the second vertical column is 7 mm to 14 mm.

[0011] Preferably, the height of the first vertical column and the second vertical column is 10 mm.

[0012] Preferably, the thickness of the first and second segmented pieces is 1.02 mm to 1.7 mm.

[0013] Preferably, the first segment includes a first vertical segment, a first curved segment, and a second vertical segment, which are connected sequentially.

[0014] Preferably, the second segment comprises an upper vertical segment, a second curved segment, and a lower vertical segment, which are connected sequentially.

[0015] Preferably, the molding mold for the breathable two-color foamed 3D printed shoe sole is a 3D precision carving mold made using a 3D printing selective laser sintering device.

[0016] Preferably, the 3D printing selective laser sintering device includes a forming cavity, a scanning system, a powder feeding system, a powder spreading system, a laser protective mirror, a piston, and a substrate. The laser protective mirror is disposed at the top of the forming cavity; the scanning system is disposed above the laser protective mirror; the powder feeding system is disposed below the forming cavity for conveying metal powder into the interior of the forming cavity; the piston is disposed below the forming cavity and located on one side of the powder feeding system; the substrate is disposed on the upper surface of the piston; the piston can drive the substrate to move up and down; the powder spreading system is disposed inside the forming cavity for spreading the metal powder conveyed to the interior of the forming cavity by the powder feeding system onto the upper surface of the substrate; the scanning system uses a laser as an energy source, scans the metal powder bed on the upper surface of the substrate layer by layer through the laser protective mirror and according to the path planned in the 3D CAD slicing model, and the scanned metal powder melts and solidifies to achieve a metallurgical bonding effect, ultimately obtaining the 3D precision-carved mold designed by the 3D CAD slicing model.

[0017] Preferably, a protective gas inlet is provided on one side of the molding cavity, and a protective gas outlet is provided on the other side; the protective gas inlet is used to introduce protective gas into the interior of the molding cavity; the protective gas outlet is used to discharge the protective gas to the outside of the molding cavity.

[0018] Preferably, the protective gas inlet is located at an upper position on one side wall of the molding cavity; the protective gas outlet is located at a lower position on the other side wall of the molding cavity.

[0019] Preferably, the powder spreading system is a roller that can roll left and right inside the molding cavity.

[0020] Preferably, the substrate and the 3D engraving mold are surrounded by loose metal powder.

[0021] Preferably, there are two powder feeding systems, which are symmetrically distributed on the left and right sides of the piston.

[0022] Preferably, there are two powder spreading systems, and the positions of the two powder spreading systems correspond to the positions of the two powder feeding systems, respectively.

[0023] The present invention also provides an integrally molded two-color foamed waterproof and breathable functional shoe sole manufactured using the aforementioned molding die, comprising a first region, a second region, a third region, and a midsole, wherein the first region, the second region, and the third region are all located below the midsole; the second region and the midsole are formed by foaming raw materials of the same color into a T-shaped structure in longitudinal section; the first region and the midsole are formed by foaming raw materials of different colors and cross-linking them together; the third region and the midsole are formed by foaming raw materials of different colors and cross-linking them together; a first vent hole extending upwards is provided in the first region, and a second vent hole extending upwards is provided in the third region; the first vent hole penetrates the first region and the midsole from bottom to top; the second vent hole penetrates the third region and the midsole from bottom to top.

[0024] Preferably, the diameter of the first vent and the second vent is 1 mm.

[0025] Preferably, the height of the first vent and the second vent is less than or equal to 20 mm.

[0026] Preferably, the height of the first vent and the second vent is 7 mm to 14 mm.

[0027] Preferably, the height of the first vent and the second vent is 10 mm.

[0028] Preferably, a waterproof and breathable membrane is attached to the top of the midsole.

[0029] Preferably, the waterproof and breathable membrane is attached to the top of the midsole at the position through which the first and second vent holes penetrate.

[0030] Preferably, the waterproof and breathable membrane is made of a polymer material.

[0031] Preferably, the polymer material includes polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), or polytetrafluoroethylene (PTFE).

[0032] Preferably, the thickness of the waterproof and breathable membrane is between 10 μm and 25 μm.

[0033] Preferably, there is a first interval between the first region and the second region; and there is a second interval between the second region and the third region.

[0034] Preferably, the first region and the third region have the same color.

[0035] Preferably, the width of the first and second interval regions is 0.4 mm to 1.2 mm.

[0036] The present invention also provides a molding process for manufacturing an integrally molded two-color foamed waterproof and breathable functional shoe sole using the aforementioned molding mold, comprising the following steps: S1. First, place the foam material for the sole in the forefoot area and heel area of ​​the lower mold. Then, close the middle plate so that the middle plate is stacked on top of the bottom cover. At this time, the aluminum mold is located directly above the lower mold. S2. Introduce the second type of foam material for shoe soles into the middle area of ​​the aluminum mold and the lower mold; then cover the top cover, so that the bottom cover, middle plate and top cover are stacked and assembled from bottom to top; apply a predetermined first pressure and a predetermined first temperature to the assembled bottom cover, middle plate and top cover within a predetermined first time using hydraulic equipment, first heat the first and second materials in the 3D carving mold to the predetermined first temperature and maintain it for a predetermined first time, so that the first and second materials in the 3D carving mold reach a semi-foamed state; S3. Separate the bottom cover, mid plate, and top cover. Separate the semi-foamed midsole from the aluminum mold. After removing the mid plate, reassemble the top cover and bottom cover seamlessly. Then, apply a predetermined second pressure and a predetermined second temperature to the assembled top cover and bottom cover within a predetermined second time period. This allows the raw materials of different colors, raw material one and raw material two, to fully foam, ultimately forming the one-piece molded two-color foamed waterproof and breathable functional sole.

[0037] Preferably, before injecting the first and second raw materials for shoe sole foaming, a release agent is first applied to the forefoot area, middle area, heel area of ​​the shoe sole, as well as the walls of the aluminum mold, the first and second dividing pieces, the first vertical column and the second vertical column of the lower mold.

[0038] Preferably, the predetermined first time is 30 seconds.

[0039] Preferably, the predetermined first pressure is 100 kg to 140 kg.

[0040] Preferably, the predetermined first temperature is set between 175°C and 177°C.

[0041] Preferably, the predetermined second time is 30 seconds.

[0042] Preferably, the predetermined second pressure is 100 kg to 140 kg.

[0043] Preferably, the predetermined second temperature is set between 175°C and 177°C.

[0044] Compared with the prior art, the beneficial effects of the present invention are: This invention uses 3D printing technology to create an integrated mold. Because the mold itself is made of metal alloy powder, it can be 3D printed with extreme precision and hardness, down to the millimeter and micrometer level. The two-color foamed waterproof and breathable sole made using this mold is an integrated mold with perforated breathable and waterproof features.

[0045] The biggest difference between the one-piece molded two-color foamed waterproof and breathable outsole made using the mold described in this invention and other existing foamed outsoles, and also the core innovation of this outsole, is that this outsole is a one-piece molded foamed outsole with built-in perforations. This is because commercially available foamed outsoles do not have perforations, and even if they do, they are not one-piece molded; they are all added later. The technical challenge of this outsole lies in the one-piece molding and perforation of the foamed outsole to achieve its waterproof and breathable functions. Attached Figure Description

[0046] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the specific embodiments of this application to explain the technical solutions of the present invention and do not constitute a limitation on the technical solutions of the present invention.

[0047] Figure 1 This is a top view of the lower mold described in this invention.

[0048] Figure 2 This is a schematic diagram of the structure of the bottom cover, middle plate and top cover assembled together according to the present invention.

[0049] Figure 3 This is a schematic diagram of the structure of the one-piece molded two-color foamed waterproof and breathable functional shoe sole described in this invention.

[0050] Figure 4 This is a schematic diagram of the 3D printing selective laser sintering device described in this invention. Implementation

[0051] The invention is described in more detail below to aid in understanding it.

[0052] like Figures 1 to 3As shown, the one-piece molded dual-color foamed waterproof and breathable functional sole of the present invention includes a first region 101, a second region 102, a third region 103, and a midsole 104. The first region 101, the second region 102, and the third region 103 are all located below the midsole 104. The second region 102 and the midsole 104 are T-shaped structures formed by foaming raw materials of the same color. The first region 101 and the midsole 104 are foamed and cross-linked together with raw materials of different colors. The third region 103 and the midsole 104 are foamed and cross-linked together with raw materials of different colors. The first region 101 is provided with a first vent 1011 extending from bottom to top, and the third region 103 is provided with a second vent 1031 extending from bottom to top. The first vent 1011 penetrates the first region 101 and the midsole 104 from bottom to top. The second vent 1031 penetrates the third region 103 and the midsole 104 from bottom to top.

[0053] Preferably, the diameter of the first vent 1011 and the second vent 1031 is 1 mm.

[0054] Preferably, the height of the first vent 1011 and the second vent 1031 is less than or equal to 20 mm.

[0055] Preferably, the height of the first vent 1011 and the second vent 1031 is 7 mm to 14 mm.

[0056] Preferably, the height of the first vent 1011 and the second vent 1031 is 10 mm.

[0057] Preferably, a waterproof and breathable membrane is attached to the top of the midsole 104.

[0058] The aforementioned waterproof and breathable membrane enables the sole of the shoe described in this application to have both breathable and waterproof functions.

[0059] This waterproof and breathable membrane material is generally made of polymer materials, such as polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), and polytetrafluoroethylene (PTFE). Waterproof and breathable membranes made from these materials have multiple functions: A. Waterproofing: It can prevent moisture from entering the shoe cavity through the vent holes on the sole (i.e., the first vent hole 1011 and the second vent hole 1031). Because the waterproof and breathable membrane adopts a unique microporous structure, it can effectively block the penetration of moisture and humidity, while allowing gas and water vapor inside the shoe cavity to pass through and be discharged to the outside of the shoe cavity.

[0060] B. Breathability: The waterproof and breathable membrane has high breathability, which can ensure foot comfort and shoe breathability. Its unique microporous structure can control the release of water vapor and prevent external moisture from entering, keeping the inside of the shoe dry.

[0061] C. Durability: Waterproof and breathable membranes are wear-resistant, aging-resistant, and corrosion-resistant, and can maintain their performance and shape for a long time. They have good tensile and tear resistance and can be used in various environments.

[0062] D. Comfort: Waterproof and breathable membranes are usually soft, thin, and conform to the body, making them more comfortable and fit the sponge fabric of shoes, bags, and other items.

[0063] E. Environmental friendliness: Waterproof and breathable membranes are usually made of environmentally friendly materials, which do not produce harmful substances and have no negative impact on the environment and human health.

[0064] In addition, the waterproof and breathable membrane also uses nanotechnology, and its thickness is generally between 10μm and 25μm.

[0065] Preferably, the waterproof and breathable membrane is attached to the top of the midsole at the position through which the first and second vent holes penetrate.

[0066] Preferably, a first interval 1021 is provided between the first region 101 and the second region 102; and a second interval 1022 is provided between the second region 102 and the third region 103.

[0067] Preferably, the first region 101 and the third region 103 have the same color.

[0068] Preferably, the width of the first interval region 1021 and the second interval region 1022 is 0.4 mm to 1.2 mm.

[0069] The one-piece molded two-color foamed waterproof and breathable functional shoe sole of the present invention uses a molding mold including a bottom cover 11, a middle plate 12 and a top cover 13 during the foaming process. A lower mold 111 is provided in the middle of the bottom cover 11, and an aluminum mold 121 is provided in the middle of the middle plate 12. The lower mold 111 includes a forefoot area 1, a middle area 2 and a heel area 3 of the sole. The forefoot area 1 and the middle area 2 are separated by a first dividing piece 4; the middle area 2 and the heel area 3 are separated by a second dividing piece 5; a plurality of first vertical columns 131 are provided in the forefoot area 1; and a plurality of second vertical columns 331 are provided in the heel area 3.

[0070] Preferably, the forefoot area 1 of the sole is further provided with a plurality of first grooves 132.

[0071] Preferably, the heel area 3 of the sole is further provided with a plurality of second grooves 332.

[0072] Preferably, when the bottom cover 11, the middle plate 12 and the top cover 13 are stacked and assembled together from bottom to top, the aluminum mold 121 is located directly above the lower mold 111.

[0073] Preferably, the thickness of the first segment 4 and the second segment 5 is 1.02 mm to 1.7 mm.

[0074] Preferably, the diameter of the first vertical column 131 and the second vertical column 331 is less than or equal to 1 mm.

[0075] Preferably, the diameter of the first vertical column 131 and the second vertical column 331 is 0.2 mm to 0.8 mm.

[0076] Preferably, the height of the first vertical column 131 and the second vertical column 331 is less than or equal to 20 mm.

[0077] Preferably, the height of the first vertical column 131 and the second vertical column 331 is 7 mm to 14 mm.

[0078] Preferably, the height of the first vertical column 131 and the second vertical column 331 is 10 mm.

[0079] Preferably, the first segment 4 includes a first vertical segment 41, a first curved segment 42, and a second vertical segment 43, which are connected in sequence.

[0080] Preferably, the second segment 5 includes an upper vertical segment 51, a second curved segment 52, and a lower vertical segment 53, which are connected in sequence.

[0081] In the existing technology, the molds used for two-color foam shoe soles do not require the first and second dividing pieces, nor do they require the first vertical column 131 and the second vertical column 331. Therefore, they can be manufactured using conventional sand casting molding processes. The function of the first vertical column 131 and the second vertical column 331 is to form the first vent 1011 and the second vent 1031.

[0082] The standard process for sand casting molds is as follows: Step 1: Carve the wooden model according to the drawings; The second step is to make a plaster mold based on the wooden mold using sand casting. The plaster mold is hollow inside. The third step is to heat the metal material, such as aluminum, iron or copper, and pour the liquid metal material formed after heating into the plaster mold to cool and solidify. Step 4: Remove the outer shell and then take out the metal mold blank inside; The fifth step is to clean the initial mold, then carve it according to the 3D drawings, carving out the details and patterns. After that, it is polished and refined to obtain a standard metal mold for shoe soles.

[0083] Because the existing two-color foamed shoe sole does not have many requirements for the mold, it does not need to set the first vertical column 131 and the second vertical column 331, and it does not have many requirements for conventional foaming technology. As long as the temperature, time and pressure reach certain values, the entire foaming process of the two-color shoe sole raw material can be completed.

[0084] The mold requirements for the one-piece molded two-color foamed waterproof and breathable functional shoe sole of the present invention are different from those of the two-color foamed shoe sole in the prior art.

[0085] The mold for manufacturing the one-piece molded two-color foamed waterproof and breathable functional sole of this invention requires the setting of a first vertical column 131 and a second vertical column 331 to form the first ventilation hole 1011 and the second ventilation hole 1031. The diameters of the first vertical column 131 and the second vertical column 331 need to be very thin, and the hardness of the first vertical column 131 and the second vertical column 331 needs to be very high to ensure that the foamed sole can be perforated smoothly during the molding process. However, the molds formed by traditional sand casting process cannot meet these standards and requirements. On the one hand, the metal materials used in traditional molds are mostly aluminum and iron, and the hardness of these materials does not meet the standards and requirements for the pressure and temperature of sole molding. On the other hand, the traditional mold sand casting process simply cannot produce the columnar mold effect, that is, it cannot achieve the effect of sole perforation.

[0086] To address the aforementioned issues, the mold used in the foaming process of the one-piece molded two-color foamed waterproof and breathable functional shoe sole of this invention is a 3D precision-carved mold made using a 3D printing selective laser sintering device.

[0087] The core innovation of this invention lies in the change of the mold forming process. Firstly, the mold for this one-piece molded foam sole does not employ the traditional sand casting process, but rather a new 3D printing selective laser sintering (SLM) technology. Secondly, the material of the mold for this one-piece molded foam sole is no longer traditional metals such as aluminum, copper, and iron, but rather 316L metal powder or mold steel powder, mainly containing elements such as molybdenum, iron, chromium, and nickel, thus ensuring the strength, hardness, and toughness of the metal powder material. The fineness of this metal powder can achieve a surface roughness of 4μm-10μm, so 3D laser sintering technology can be used to create strips and columns with a diameter of 0.2-0.8 mm in the mold, while also meeting the pressure and temperature requirements during mold production.

[0088] Selective laser sintering (SLS) is a major technique in additive manufacturing of metal materials. This SLS technology uses a laser as the energy source and scans the metal powder bed layer by layer according to a pre-planned path in a 3D CAD slicing model. The scanned metal powder melts and solidifies to achieve a metallurgical bond, ultimately obtaining the metal part designed in the model. The melting precision of the metal alloy powder is between 0.2 and 0.8 mm (because the surface roughness of 316L stainless steel powder can reach 4μm-10μm), fully capable of melting 1 mm thick slices and first vertical columns 131 and second vertical columns 331 with diameters of 0.2 mm to 0.8 mm. Simultaneously, due to the hardness of the metal alloy powder, even slices or columns only 1 mm thick and 10 mm high can withstand hundreds of kilograms of pressure from a press without bending or breaking, thus fully meeting the foaming requirements for shoe soles in this invention.

[0089] like Figure 4As shown, the 3D printing selective laser sintering device includes a forming cavity 71, a scanning system 72, a powder feeding system 73, a powder spreading system 74, a laser protective mirror 75, a piston 78, and a substrate 79. The laser protective mirror 75 is disposed at the top of the forming cavity 71; the scanning system 72 is disposed above the laser protective mirror 75; the powder feeding system 73 is disposed below the forming cavity 71 and is used to transport metal powder into the interior of the forming cavity 71; the piston 78 is disposed below the forming cavity 71 and located to one side of the powder feeding system 73; the substrate 79 is disposed on the upper surface of the piston 78; the piston 78 can drive the substrate 79 to move up and down; the powder spreading system 74 is disposed inside the forming cavity 71 and is used to spread the metal powder transported to the interior of the forming cavity 71 by the powder feeding system 73 onto the upper surface of the substrate 79; the scanning system 72 uses a laser as an energy source, scanning through the laser protective mirror 75 and according to 3D CAD... The planned path in the slicing model is scanned layer by layer on the metal powder bed on the upper surface of the substrate 79. The scanned metal powder is melted and solidified to achieve a metallurgical bonding effect, and finally the 3D precision carving mold 81 designed by the three-dimensional CAD slicing model is obtained.

[0090] Preferably, a protective gas inlet 76 is provided on one side of the molding cavity 71, and a protective gas outlet 77 is provided on the other side; the protective gas inlet 76 is used to introduce protective gas into the interior of the molding cavity 71; the protective gas outlet 77 is used to discharge the protective gas to the outside of the molding cavity 71.

[0091] Preferably, the protective gas inlet 76 is located at an upper position on one side wall of the molding cavity 71; the protective gas outlet 77 is located at a lower position on the other side wall of the molding cavity 71.

[0092] Preferably, the powder spreading system 74 is a roller that can roll left and right inside the forming cavity 71.

[0093] Preferably, the substrate 79 and the 3D engraving mold 81 are surrounded by loose metal powder 80.

[0094] Preferably, there are two powder feeding systems 73, which are symmetrically distributed on the left and right sides of the piston 78.

[0095] Preferably, there are two powder spreading systems 74, and the positions of the two powder spreading systems 74 correspond to the positions of the two powder feeding systems, respectively.

[0096] During the fabrication of a 3D precision mold using the aforementioned 3D printing selective laser sintering device, the powder feeding system 73 can move up and down. The upward movement of the powder feeding system 73 delivers metal powder into the interior of the molding cavity 71. The left and right rolling of the powder spreading system 74 inside the molding cavity 71 spreads the metal powder delivered by the powder feeding system 73 onto the upper surface of the substrate 79. The layer-by-layer scanning of the scanning system 72 melts the metal powder on the upper surface of the substrate 79, and then the molten metal powder solidifies to achieve a metallurgical bonding effect, ultimately obtaining the 3D precision mold 81 designed by the three-dimensional CAD slice model.

[0097] The structural properties of the metal material used to manufacture the 3D precision-carved mold differ from existing technologies. Existing technologies typically use aluminum, iron, or copper as the metal material in conventional sand casting processes. These materials are not particularly hard, and under certain pressure and temperature, they must be in large, bulky shapes, not as tiny dots or columns (1 mm in diameter). Thin shapes would be bent or broken during conventional shoe sole molding. Therefore, conventional mold metal materials, such as aluminum, iron, and copper, cannot meet the required precision and hardness of the mold. Only new metal alloy powders are suitable. The metal powder material used in this application for manufacturing the 3D precision-carved mold is 316L stainless steel powder or mold steel powder. 316L stainless steel powder or mold steel powder contains elements such as molybdenum, iron, chromium, and nickel, thus ensuring the strength, hardness, and toughness of the metal powder material.

[0098] It is thanks to the cylindrical mold printed by the new 3D printing selective laser sintering technology that the basic standard diameter of the cylinder is about 1 mm, and the height can be 7 to 14 mm depending on the requirements of the sole. Some soles are even as high as 20 mm. It is because of this cylindrical mold that the breathable perforations of the one-piece molded foam sole are possible.

[0099] This invention also provides a molding process for a one-piece molded two-color foamed waterproof and breathable functional shoe sole, including the following steps: S1. First, place the first type of foam material (such as black) in the forefoot area 1 and heel area 3 of the lower mold 111; then close the middle plate 12 so that the middle plate 12 is stacked on top of the bottom cover 11. At this time, the aluminum mold 121 is located directly above the lower mold 111. S2. Introduce the second type of foam material for shoe soles (e.g., white) into the middle area 2 of aluminum mold 121 and lower mold 111; then cover with the upper cover 13, so that the bottom cover 11, middle plate 12 and upper cover 13 are stacked and assembled from bottom to top; apply a predetermined first pressure (the pressure of mold closing is 100-140 kg) and a predetermined first temperature (generally set between 165-185 degrees) to the assembled bottom cover 11, middle plate 12 and upper cover 13 within a predetermined first time (generally each press time is between 25-45 seconds) using a hydraulic press. First heat the foam material (i.e., raw material one and raw material two) in the 3D carving mold to the predetermined first temperature and maintain it for a predetermined first time. At this time, the temperature is not enough to make the foam material fully foamed, that is, in a semi-foamed state. S3. Separate the bottom cover 11, the middle plate 12, and the top cover 13. Separate the semi-foamed midsole 104 from the aluminum mold 121. After removing the middle plate 12, reassemble the top cover 13 and the bottom cover 11 seamlessly. Then, within a predetermined second time (about 30 seconds), apply a predetermined second pressure (100-140 kg) and a predetermined second temperature (between 165 degrees and 185 degrees) to the assembled top cover 13 and bottom cover 11. This allows the foaming materials (i.e., raw material one and raw material two) to fully foam, ultimately forming the one-piece molded two-color foamed waterproof and breathable functional shoe sole of the present invention.

[0100] Preferably, before injecting the first and second raw materials for shoe sole foaming, a release agent is first applied to the walls of the forefoot area 1, middle area 2, heel area 3 of the shoe sole, as well as the aluminum mold 121, the first dividing piece 4 and the second dividing piece 5, the first vertical column 131 and the second vertical column 331 of the lower mold 111.

[0101] Preferably, the predetermined first time is 30 seconds.

[0102] Preferably, the predetermined first temperature is between 175°C and 177°C.

[0103] The one-piece molded two-color foamed waterproof and breathable functional sole of this invention is determined by two properties: the molding process (3D printing) of the sole mold and the molding material (synthetic metal powder) of the mold. The waterproof and breathable function of this sole is also based on these two properties; the pressure from the sole and the ball of the foot enables the sole to release air.

[0104] The one-piece molded two-color foamed waterproof and breathable functional shoe sole of this invention is one-piece molded. Thanks to 3D printing technology, a one-piece mold, including perforated mold components, can be printed, which cannot be achieved by conventional sand casting processes. Because the mold itself is made of metal alloy powder, it can be 3D printed with extreme precision and hardness, reaching the millimeter and micrometer level. The addition of perforated breathable and waterproof functions makes the shoe sole of this invention even more unique.

[0105] The preferred embodiments of the present invention have been described above, but are not intended to limit the invention. Those skilled in the art can make modifications and variations to the embodiments disclosed herein without departing from the scope and spirit of the invention.

Claims

1. A molding die for a breathable, two-color foamed 3D-printed shoe sole, characterized in that, The molding mold for the breathable dual-color foamed 3D printed shoe sole includes a bottom cover, a mid-plate, and a top cover. A lower mold is located in the center of the bottom cover, and an aluminum mold is located in the center of the mid-plate. The lower mold includes a forefoot area, a mid-section area, and a heel area. The forefoot area and mid-section area are separated by a first dividing piece; the mid-section area and heel area are separated by a second dividing piece. Multiple first vertical pillars are provided in the forefoot area; and multiple second vertical pillars are provided in the heel area.

2. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, When the bottom cover, middle plate, and top cover are stacked and assembled together from bottom to top, the aluminum mold is located directly above the lower mold.

3. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, The diameter of the first and second vertical columns is less than or equal to 1 mm.

4. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, The diameter of the first and second vertical columns is 0.2 mm to 0.8 mm.

5. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, The height of the first and second vertical columns is less than or equal to 20 mm.

6. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, The height of the first and second vertical columns is 7 mm to 14 mm.

7. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, The thickness of the first and second segments is 1.02 mm to 1.7 mm.

8. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, The first segment includes a first vertical segment, a first curved segment, and a second vertical segment, which are connected sequentially.

9. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, The second segment comprises an upper vertical segment, a second curved segment, and a lower vertical segment, which are connected sequentially.

10. The molding die for the breathable two-color foamed 3D printed shoe sole according to claim 1, characterized in that, The molding mold for the breathable two-color foamed 3D printed shoe sole is a 3D precision-carved mold made using a 3D printing selective laser sintering device.

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