BR-102024018276-A2 - MANUFACTURING PROCESS FOR A PROPULSION PLATE FOR FOOTWEAR, AND THE PROPULSION PLATE OBTAINED THROUGH SUCH A PROCESS

Abstract

The present invention relates to a manufacturing process for a propulsion plate for footwear from thermoset composites based on unsaturated polyester resin or vinyl ester, with or without graphene additives, reinforced with fiberglass or chopped carbon fiber in the form of a sheet molding compound (SMC), and a propulsion plate (1) obtained through such process, which improves the propulsion of high-performance footwear in physical activities, as well as contributing to better comfort and protection of the feet.

Inventors

• LUIS GUSTAVO PANEGASSI BRITZKI
• Marcelo Panegassi Britzki

Assignees

• PLACTEX INDÚSTRIA E COMÉRCIO DE PLÁSTICOS LTDA.

Dates

Publication Date

20260317

Application Date

20240905

Claims (4)

1. 1. Manufacturing process of a propulsion plate for footwear from SMC (Sheet Molding Compound) mattress-shaped composites, CHARACTERIZED by comprising: - depositing a layer of paste onto the film; - after exiting the vat, passing the mixture through a fiber cutter, which deposits a thick layer of fiber, forming a mattress of chopped fiber on the paste; - after receiving the fiber mattress, the lower film meets another film that has passed through another dosing vat (Vat 2), which is located at the top of the machine, which also has a layer of paste equal to that of the lower film, thus forming a sandwich of lower film/paste/fiber/paste/film; - passing the sandwich through the compaction sector, to impregnate the fiber with the paste; - winding the compacted material in laminar form; - taking the compacted material in laminar form to a maturation chamber until it reaches the appropriate molding viscosity; - To mold the compacted material into a laminar form in the shape of the plates to be molded, by a compression process in a steel or other metal mold, at a minimum temperature of 80°C, and at a minimum pressure of 50 kg/cm2; - To remove the material from the mold and finish the propellant plates.
2. 2. Manufacturing process for a propulsion plate for footwear from SMC (Sheet Molding Compound) mattress-shaped composites, according to claim 1, CHARACTERIZED by the raw materials used in the SMC composite formulation being as follows: - thermosetting resin from 10.0% to 40.0% by weight; - thermoplastic additive from 0.0% to 15.0% by weight; - strength additive from 0.0% to 5.0% by weight; - catalyst from 0.3% to 2.0% by weight; - mineral fillers from 0.0% to 40.0% by weight; - release agent from 1.0% to 3.0% by weight; - pigment from 0.0% to 3.0% by weight; - chopped fiber from 25.0% to 70.0% by weight; - thickening agent from 0.2% to 1.5% by weight.
3. 3. Manufacturing process for a propulsion plate for footwear from SMC (Sheet Molding Compound) mattress-shaped composites, according to claim 1 or 2, CHARACTERIZED by the raw materials being selected from the following group: - thermosetting resin - unsaturated polyester/vinyl ester; - thermoplastic additive - polystyrene/acrylic resins/polyvinyl acetate/adipates/PVAC/among others; - strength additive - graphene in all its forms/carbon nanotubes/carbon fiber powder or ground; - catalyst - organic peroxides; - mineral fillers - alumina/calcium carbonate/calcite/talc/kaolin/quartz/among others; - release agent - stearates/stearins/waxes/liquid release agents; - pigment - organic and inorganic pigments; - reinforcement - chopped fiberglass/chopped carbon fiber; - Thickening agent - magnesium oxide/magnesium hydroxide/calcium oxide/calcium hydroxide/among others.
4. 4. Propulsion plate (1), CHARACTERIZED by being obtained through the manufacturing process as defined in any of the preceding claims.

Description

Field of Invention [0001] The present invention relates to a manufacturing process for a propulsion plate for footwear from thermoset composites based on unsaturated polyester resin or vinyl ester, with or without graphene additives, reinforced with fiberglass or chopped carbon fiber in the form of a sheet molding compound (SMC), and a propulsion plate obtained through such a process, which improves the propulsion of high-performance footwear in physical activities, as well as contributing to better comfort and protection of the feet. Fundamentals of the Invention [0002] Currently, various types of midsole plates for footwear are being developed, predominantly for footwear for physical activities, which are adapted internally to the soles of the shoes to provide greater comfort and protection to the feet. [0003] Among the boards available on the market, the most common are those made from pre-impregnated epoxy resins or engineering thermoplastic polymers, reinforced with fabric and/or continuous carbon fiber strands, or those made from unreinforced thermoplastic polymers. [0004] Although epoxy resin boards reinforced with carbon or glass fiber perform excellently in this application, their manufacturing process is complex and expensive due to the physical characteristics and high cost of raw materials, the long curing cycle time spent molding the parts, and the type of finish used in their manufacture. These factors result in a product with a very high cost and a process with relatively low production capacity, which requires a high investment in equipment by manufacturers to meet market demand. [0005] In panels produced with engineering thermoplastic polymers reinforced with carbon fiber, the manufacturing process is quite complex and expensive, and their formulation is composed of high-cost raw materials, making the price of the panels extremely high. [0006] Regarding plates produced from thermoplastic polymers, there are several limitations to their use. Due to their low performance in terms of mechanical properties, mainly in relation to the modulus of elasticity (rigidity), which is the main characteristic in the propulsive effect of the plate, the results obtained by these plates fall well below the plates that the market needs. For this application, we can define that the higher the modulus of elasticity, the greater the energy return that the plate provides to the user, and therefore the better the plate's performance. [0007] Another important factor regarding thermoplastic polymers is their physical characteristics in relation to the elastic resistance limit; that is, when this limit is exceeded, the piece does not return to its original shape and consequently there is a significant loss of performance. Thus, there is a reduction in the propulsion effect over the time the footwear is used. [0008] In order to overcome the problems mentioned above, there are some manufacturing processes and propulsion plates for footwear in the state of the art, among which we highlight patent document BR PI0905472-3, which refers to an innovative manufacturing process by injection molding of the shoe upper assembly insole that eliminates the need for a steel core. The manufacturing process for the assembly insole comprises the injection molding of the assembly insole in polyamide with the addition of fiberglass for its structure. The percentage of fiberglass addition is 10 to 50% of the final weight of the insole. The injection process requires precise control of the raw material temperature during the plasticizing stage inside the injection molding machine barrel, as well as the mold temperature, with plasticizing conducted in the range of 230 to 300°C and the mold temperature in the range of 30 to 80°C. Preferably, the injection molding of the assembly insole is done with polyamide and a 33% addition of fiberglass, relative to the final weight of the insole, with the raw material temperature during plasticization being in the range of 230 to 260°C and the mold temperature in the range of 30 to 50°C. [0009] Document DE102005050861 discloses a puncture-resistant shoe sole that utilizes a textile consisting of layers of polyester and fiberglass fabric laid one on top of the other and connected to each other by a composite layer placed between the fabric layers. The composite layer is composed of thermal fusion adhesive and heat-sealable foam film. The fabric layers or their yarns also consist of, for example, polyester, polyamide and/or polyacrylonitrile and/or viscose and/or fiberglass or mixtures thereof. [00010] Document EP2842445 describes a method for manufacturing shoe insoles comprising the steps of: 1 - making a resin mixture by mixing a resin and a hardening agent in a container; 2 - impregnating a fiberglass fabric with the resin mixture from step 1; 3 - cutting the impregnated fiberglass fabric from step 2 according to a predetermined half-insole or insole shape; 4 - hot pressing to form a product by addin