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CN-122008609-A - Co-molded footwear component and method of making same

CN122008609ACN 122008609 ACN122008609 ACN 122008609ACN-122008609-A

Abstract

The invention provides a co-molded shoe part and a preparation method thereof, wherein the shoe part comprises an outsole and a midsole, one side of the outsole is provided with a plurality of anchoring structures which can be in the form of bulges, depressions or through holes, the midsole is formed by physical foaming through a supercritical fluid and is combined with the outsole at the same time, and a part of the midsole is completely combined with the anchoring structures, so that the firmness of the outsole and the midsole after being combined is enhanced in a mode of increasing the contact surface area. The preparation method is that the prepared outsole is moved into a mould, the pressure value of the gas in the mould is controlled, and after a thermoplastic foaming fluid material is injected, the thermoplastic foaming fluid material is foamed and molded into the midsole by a decompression mode and is combined with the outsole into a whole.

Inventors

  • YANG ZONGLIN
  • ZHANG YUDA

Assignees

  • 福建大丰投资集团有限公司

Dates

Publication Date
20260512
Application Date
20241111

Claims (20)

  1. 1. A co-molded shoe component comprising: The outsole comprises a combined surface and a plurality of anchoring structures, wherein the anchoring structures are positioned on the combined surface, the sum of the surface areas of the anchoring structures and the combined surface is A, and the ratio of the surface area A to the surface area B of an imaginary combined surface without the anchoring structures is A/B larger than 1; the midsole is formed by physical foaming of a supercritical fluid, and comprises a bonding surface, wherein the bonding surface of the midsole is used for bonding the bonded surface and the anchoring structures.
  2. 2. A co-molded footwear component according to claim 1, wherein the a/B ratio is greater than or equal to 1.2 and less than or equal to 3.0.
  3. 3. A co-molded footwear component according to claim 1, wherein the a/B ratio is greater than or equal to 1.5 and less than or equal to 2.0.
  4. 4. A co-molded footwear component according to any of claims 1 to 3, wherein the number of anchoring structures is in the range 40 to 180 per square centimeter and the spacing between adjacent anchoring structures is greater than or equal to 0.3mm and less than or equal to 1.2mm.
  5. 5. The co-molded footwear component of claim 4, wherein the anchoring structures are each a protrusion, each protrusion having a root portion and a crest portion, the root portion connecting the bonded surface, and each protrusion having a height from the root portion to the crest portion of greater than or equal to 0.3mm and less than or equal to 1.2mm, the bonding surface of the midsole surrounding the bonded surface and the anchoring structures.
  6. 6. The co-molded footwear component of claim 5, wherein the protrusions are disposed along a first direction that is perpendicular to the bonded face of the outsole.
  7. 7. The co-molded footwear component of claim 6, wherein the top width of each projection is greater than the root width.
  8. 8. The co-molded footwear component of claim 6, wherein the top width of each projection is less than or equal to the root width.
  9. 9. The co-molded footwear component of claim 6, wherein the top width of each projection is equal to the root width, and a middle portion of each projection is greater than or less than the top width.
  10. 10. The co-molded footwear component of claim 5, wherein the outsole comprises a body and a sidewall disposed upwardly along a periphery of the body, the portion of the bonded pair of the body defining a first region and the portion of the bonded pair of the sidewall defining a second region, wherein a root width of the protrusions of the first region is less than a root width of the protrusions of the second region.
  11. 11. The co-molded footwear component of claim 10, wherein the protrusions in the first region are disposed along a first direction and the protrusions in the second region are disposed along a second direction, wherein the first direction is perpendicular to the bonded surface of the outsole and the second direction is not parallel to the first direction.
  12. 12. The co-molded shoe component of claim 11, wherein the outsole is a 3D three-dimensional printed structure.
  13. 13. A co-molded footwear component according to any of claims 1 to 3, wherein the outsole is a 3D three-dimensional printed structure.
  14. 14. The co-molded footwear component of claim 4, wherein the outsole has a bottom surface disposed opposite the bonded surface, the anchor structures are each through-holes, each through-hole penetrating the bonded surface and the bottom surface of the outsole, a portion of the bonded surface of the midsole filling the through-holes.
  15. 15. The co-molded footwear component of claim 14, wherein each through hole has an upper opening connected to the bonded surface, each through hole having a lower opening connected to the bottom surface, wherein the upper opening has a caliber less than or equal to a caliber of the lower opening.
  16. 16. The co-molded footwear component according to claim 4, wherein the anchor structures are each a recess, each recess being recessed from the bonded surface, a portion of the bonding surface of the midsole filling the recesses.
  17. 17. The co-molded footwear component of claim 1, comprising an upper co-molded with a top surface of the midsole, the top surface being disposed opposite the bonding surface.
  18. 18. A method of making a co-molded footwear component comprising the steps of: Preparing an outsole, wherein the outsole is provided with a combined surface and a plurality of anchoring structures positioned on the combined surface, and the number of the anchoring structures is 40 to 180 in the range of each square centimeter; Displacing the outsole into a mold, and reserving a foaming space in the mold; controlling the gas pressure value in the mould to be greater than or equal to 5bar and less than or equal to 50bar; Injecting a thermoplastic foaming fluid material into the foaming space of the mold, wherein the thermoplastic foaming fluid material comprises a supercritical fluid; releasing the gas pressure in the mould, and foaming the thermoplastic foaming fluid material to form a physically foamed midsole, wherein the midsole is provided with a bonding surface which bonds the bonded surface of the outsole with the anchoring structures; Opening the mold and removing a shoe component comprising the outsole and midsole.
  19. 19. The method of making a co-molded shoe component of claim 18, wherein the step for making the outsole comprises: Providing a mold, wherein a plurality of concave holes are preformed in a mold cavity, and the number of the concave holes is 40 to 180 in the range of each square centimeter; injecting a thermoplastic material into the mold, wherein the thermoplastic material fills the mold cavity and the concave holes, and cooling the thermoplastic material to form the outsole.
  20. 20. The method of making a co-molded footwear component according to claim 19, wherein the mold is a 3D metal printing mold and the indentations are structures reserved for a 3D metal printing process.

Description

Co-molded footwear component and method of making same Technical Field The present invention relates to footwear, and more particularly to a co-molded footwear component and method of making the same. Background The composition of known shoes generally comprises a sole and an upper, wherein the sole is further divided into a sole and a midsole according to the functional requirements of the user, the sole is used for touching the ground, and the midsole generally has the effect of absorbing vibration energy. The outsole, the midsole and the vamp are independent components and are combined one by one through a complicated operation mode, so that the manufacturing cost is consumed, and the manufacturing efficiency is reduced. The midsole is usually manufactured by a chemical foaming method, the problem of unstable dimensional shrinkage rate easily occurs in the manufacturing process, the situation that the dimension matching is not matched or glue overflows is caused when the midsole is adhered to the outsole by an adhesive, the midsole is required to be grinded to be carved into a proper dimension before the sole is adhered to the outsole, but the operation procedure is increased, and in addition, the adhesive has toxicity, so that the adhesive has hidden danger of harming the health of operators and also can destroy the ecological environment. However, the midsole and the outsole still need to be chemically reacted to produce an adhesion effect, and the injected PU contains a cross-linking agent, so that the midsole formed by the PU injection is difficult to recycle. In addition, the midsole is manufactured in a mode of injecting physical foaming and is co-molded with the outsole, however, in the injection physical foaming process, the generated temperature and pressure are far lower than the conditions of the traditional co-molding, so that the adhesion between the midsole and the outsole formed by physical foaming is often lower than a safety standard, and potential safety hazards caused by peeling of the midsole during the wearing process of a wearer are hidden. Disclosure of Invention In view of the above, an object of the present invention is to provide a co-molded shoe component and a method for manufacturing the same, which can improve the bonding strength between components of the shoe component without using an adhesive. In order to achieve the above object, the present invention provides a co-molded shoe part comprising a outsole and a midsole, wherein the outsole comprises a bonded surface and a plurality of anchor structures, the anchor structures are positioned on the bonded surface, the sum of the surface areas of the anchor structures and the bonded surface is A, the ratio of the surface area A to the surface area B of a bonded surface which is imaginary and does not have the anchor structures is A/B greater than 1, the midsole is formed by physical foaming with a supercritical fluid, the midsole comprises a bonded surface, and the bonded surface of the midsole is bonded with the anchor structures. The present invention also provides a method of preparing a co-molded footwear component, comprising preparing an outsole having a bonded surface and a plurality of anchor structures located on the bonded surface, the number of anchor structures having 40 to 180 per square centimeter, displacing the outsole into a mold with a foaming space reserved in the mold, controlling a gas pressure value in the mold to be greater than or equal to 5bar and less than or equal to 50bar, injecting a thermoplastic foaming fluid material into the foaming space of the mold, the thermoplastic foaming fluid material comprising a supercritical fluid, releasing the gas pressure in the mold, foaming the thermoplastic foaming fluid material to form a physically foamed midsole, the midsole having a bonding surface, the bonding surface bonding the bonded surface of the outsole and the anchor structures, opening the mold, and removing a footwear component comprising the outsole and the midsole. The invention has the advantages that the midsole which is physically foamed is combined with the outsole in the die in a co-molding mode, the outsole is provided with a plurality of anchoring structures, the contact surface area with the midsole can be increased, the aim of improving the combination strength of the midsole and the outsole is achieved, and in the process of combining the midsole and the midsole, an adhesive is not required. Drawings FIG. 1 is a perspective view of a co-molded footwear component according to a preferred embodiment of the invention; FIG. 2 is a cross-sectional view taken in the direction 2-2 of FIG. 1; FIG. 3 is an enlarged view of a portion of the portion indicated by the reference A in FIG. 2; FIG. 4 is a perspective view of the outsole among the co-molded shoe components of the preferred embodiment of the invention described above; FIG. 5 is a top view of FIG. 4; FIG. 6 is a cross-sectional view take