KR102625246B1 - Upcycling Shoes Recycled From Scrap And Method for Manufacuring the Same - Google Patents

Abstract

Fiber scrap such as polyester, wool, nylon, etc., and expanded foam such as EVA or polyurethane (PU) generated during the manufacturing process of shoe uppers and soles. ) It relates to upcycling shoes made of non-woven uppers and foam soles manufactured by recycling scrap, and a manufacturing method thereof. The manufacturing method of upcycling shoes according to the present invention is (S1) fabric generated in the shoe upper or clothing manufacturing process. Quickly freezing the scrap and pulverizing it to produce waste fiber with a length of 0.3 to 10 mm; (S2) manufacturing a nonwoven fabric using the waste fiber produced in step (S1); (S3) manufacturing a recycled upper by cutting the nonwoven fabric prepared in step (S2); (S4) producing pulverized foam by rapidly freezing and pulverizing foam resin scraps generated during the shoe sole manufacturing process; (S5) mixing the pulverized foam prepared in step (S4) with a foam resin and foam molding to produce a recycled shoe sole; And, (S6) bonding the lower part of the recycled upper made in step (S3) with the recycled shoe sole made in step (S5).

Description

Upcycling Shoes Recycled From Scrap And Method for Manufacuring the Same}

The present invention relates to shoes and a method of manufacturing the same, and more specifically, to the use of fiber scraps (polyester, wool, nylon, etc.) generated during the manufacturing process of the upper and sole of the shoe. It relates to upcycling shoes composed of a non-woven upper and a foam sole manufactured by recycling scraps of foam such as scrap and EVA or polyurethane (PU), and a method of manufacturing the same.

Shoes are worn to protect the human body's feet and are manufactured and sold in various shapes and types. However, they usually consist of an upper that covers and protects the instep and ankle area, and a shoe that protects the sole and provides friction with the ground. It consists of a shoe sole that is raised to improve walking ability and at the same time relieves the impact on the soles of the feet when walking.

During the shoe manufacturing process, a large amount of fiber (polyester, wool, nylon, etc.) scrap and foam (EVA, PU, etc.) scrap are generated during the upper and sole manufacturing process. In particular, when industrial waste is put back into the process, recycled, and applied to the final product, waste disposal costs and carbon emissions are reduced.

In addition, as the issue of climate change has recently emerged, 65 countries around the world have declared carbon neutrality, and as 'carbon zero', a measure to absorb as much carbon dioxide as it emits, has become an issue, carbon neutrality-related policies for low carbonization are being implemented in Korea as well. there is.

In accordance with these policies, various industries are also applying eco-friendly material processes, and in the shoe industry in particular, there is a trend to produce only eco-friendly products or to implement eco-friendly marketing by brands themselves.

Accordingly, the global shoe industry is currently making efforts to recover shoes or industrial waste to replace raw materials and improve eco-friendly culture and eco-friendly index through recycling and upcycling.

For example, Domestic Patent No. 10-1248276 discloses a method of manufacturing recycled synthetic leather by recycling scrap, which is waste remaining from the shoe manufacturing process. The method of producing recycled synthetic leather in the registered patent involves pulverizing natural leather scraps, polyurethane skin scraps, synthetic leather scraps, fiber scraps, etc. to a certain size, then spreading them on a polyurethane resin layer, drying them again, and pressing them. This is a method of manufacturing recycled synthetic leather.

In addition, in Domestic Patent Publication No. 10-2019-0000051, collagen long fibers are separated and recovered from by-products generated after shoe upper pattern cutting during the shoe manufacturing process by an appropriate treatment method, and then converted into short fibers into shaving scrap and Manufacturing of upcycling leather sheets using collagen long fibers to solve the limited usability of conventional recycled leather materials with insufficient physical properties by mixing them and then treating them again with chemicals to provide materials that can be applied in various fields. A method is disclosed.

However, conventional recycled raw materials for shoes such as those described above use a method of extracting recycled raw materials through chemical decomposition. In this case, the processing conditions are difficult, and there are limitations due to high manufacturing costs and complex manufacturing processes, and it is difficult to obtain sufficient physical properties. There is a difficult problem.

Republic of Korea Patent No. 10-1248276 Republic of Korea Patent Publication No. 10-2019-0000051

The present invention is intended to solve the above problems, and the purpose of the present invention is to reduce the manufacturing cost and simplify the process by manufacturing fabric scraps and foam scraps generated during the manufacturing process of shoes into recycled materials through physical grinding, The aim is to provide upcycling shoes and a manufacturing method that can obtain sufficient physical properties compared to raw materials.

The upcycling shoes according to the present invention for achieving the above purpose are recycled non-woven fabrics manufactured using waste fibers with a length of 0.3 to 10 mm obtained by rapidly freezing and pulverizing fabric scraps generated in the shoe upper or clothing manufacturing process. upper; And, a recycled shoe sole that is foam-molded by mixing foam scrap obtained by rapid freeze-grinding of foam scrap generated in the shoe sole manufacturing process with a foam resin and attached to the lower end of the recycled upper.

The recycled shoe sole may be mixed with waste fibers used to manufacture the non-woven fabric that makes up the recycled upper.

The nonwoven fabric forming the recycled upper is laminated by binding a sponbond nonwoven fabric to a fiber web made using the waste fiber, and an impregnating solution containing 2 to 10% by weight of polyvinyl alcohol, 1 to 3% by weight of softener, and the balance purified water. After being impregnated and shrunk, a resin composition obtained by mixing any one of water-based polyester resin, water-based acrylic resin, and water-based polyurethane resin with purified water may be deposited.

The method of manufacturing upcycling shoes according to the present invention,

(S1) rapidly freezing fabric scraps generated in the shoe upper or clothing manufacturing process and then pulverizing them to produce waste fibers with a length of 0.3 to 10 mm;

(S2) manufacturing a nonwoven fabric using the waste fiber produced in step (S1);

(S3) manufacturing a recycled upper by cutting the nonwoven fabric prepared in step (S2);

(S4) producing pulverized foam by rapidly freezing and pulverizing foam resin scraps generated during the shoe sole manufacturing process;

(S5) mixing the pulverized foam prepared in step (S4) with a foam resin and foam molding to produce a recycled shoe sole; and,

(S6) bonding the lower part of the recycled upper made in step (S3) with the recycled shoe sole made in step (S5);

may include.

When mixing the pulverized foam with the foam resin in step (S5), a recycled shoe sole can be manufactured by mixing the waste fibers prepared in step (S1).

In the step (S2), a mixing process in which waste fibers are put into a hopper and mixed, a carding process in which the mixed fibers are arranged as if combing after going through the blending process, and the size and thickness of the listed fibers are adjusted. A process of forming (lapping) a fiber web by spreading and overlapping it to form a fiber web and interposing spunbonded non-woven fabric as a reinforcement material between the fiber webs. Needle punching is a process of binding and laminating the fiber web and spunbonded non-woven fabric. ) process, a shrinking process in which the needle-punched fiber web is impregnated with an impregnation solution containing 2-10% by weight of polyvinyl alcohol, 1-3% by weight of softener, and the balance purified water, and then shrunk, the shrunken fiber web is 100-170% Non-woven fabric is made through a compression process of compressing at a temperature of ℃, and a calendering process of calendering the compressed fiber web to produce non-woven fabric, and the non-woven fabric is mixed with one of water-based polyester resin, water-based acrylic resin, and water-based polyurethane resin. A non-woven fabric can be manufactured by spraying and drying a resin composition mixed with purified water.

According to the present invention, waste fibers and foam scraps are obtained by rapidly freezing and pulverizing fabric scraps and foam scraps generated during the manufacturing process of shoes or clothing, and using the waste fibers, non-woven fabric suitable for shoe uppers is manufactured to produce shoe uppers. In addition to manufacturing, shoe soles can be foam molded using crushed foam.

Therefore, by manufacturing upcycled shoes made entirely of recycled materials, the manufacturing cost can be lowered and the process can be simplified, while sufficient physical properties can be obtained compared to raw materials.

1 is a diagram showing upcycling shoes according to an embodiment of the present invention.
Figure 2 is a schematic diagram explaining the manufacturing method of upcycling shoes according to the present invention.
Figure 3 is a flow chart explaining the manufacturing method of upcycling shoes according to the present invention.

The embodiments described in this specification and the configurations shown in the drawings are only preferred examples of the disclosed invention, and at the time of filing this application, there may be various modifications that can replace the embodiments and drawings in this specification.

Hereinafter, with reference to the attached drawings, upcycling shoes made from recycled scrap and a manufacturing method thereof will be described in detail according to the embodiments described below. In the drawings, like symbols represent like components.

Referring to Figures 1 and 2, the upcycling shoe according to an embodiment of the present invention includes a recycled upper 10 made of non-woven fabric 12 made using waste fiber 11 obtained from fabric scrap, and foam scrap. It includes a recycled sole (20) manufactured using the ground foam material (21) obtained from and attached to the lower end of the recycled upper (10).

The recycled upper (10) is made of non-woven fabric (12) manufactured using waste fiber (11) obtained by rapidly freezing and pulverizing fabric scraps generated in the shoe upper or clothing manufacturing process. The fabric scraps are manufactured using cutter mill equipment. After cutting it to a predetermined length, it is frozen by putting it in a cryogenic chamber supplied with a cryogenic fluid such as liquid nitrogen, and pulverized with a grinder in the cryogenic chamber to produce waste fibers (11) with a length of 0.3 to 10 mm. After this, it becomes a non-woven fabric (12) made using the manufactured waste fiber.

As shown in Figure 3, the nonwoven fabric 12 is a mixing process in which waste fibers with a length of 0.3 to 10 mm manufactured through a grinding process after rapid freezing are put into a hopper and mixed, and the mixed fibers are produced after going through a blending process. The carding process involves arranging the fibers as if combing them, forming a fiber web by spreading and overlapping them to control the size and thickness of the fibers, and at the same time using spunbonded non woven fabric as a reinforcing material between the fiber webs. An intervening process, a needle punching process that binds and laminates the fiber web and sponbond nonwoven fabric, a shrinkage process that shrinks the needle-punched fiber web after impregnating it with an impregnation solution mixed with polyvinyl alcohol, softener, and purified water, Non-woven fabric is made through a compression process in which the shrunken fiber web is compressed at a temperature of 100 to 170 degrees Celsius, and a calendering process in which the compressed fiber web is calendered to produce non-woven fabric. Manufactured by spraying a resin composition on the non-woven fabric and drying it. It can be.

The waste fiber 11 mixed in the mixing process is preferably a mixture of 30 to 55% by weight of polytrimethylenterephthalate (PTT) fiber, 20 to 45% by weight of nylon fiber, and 25 to 50% by weight of polyester fiber. PTT fibers can be mixed to impart mechanical properties such as tensile strength, tear strength, and bursting strength to nonwoven fabrics. The nylon fiber may be one or more selected from the group consisting of nylon 6, nylon 66, nylon 610, nylon 612, nylon 46, nylon 11, and nylon 12. Polyester fiber has an excellent elastic recovery rate, so it can impart elasticity and flexibility to nonwoven fabrics after processing and improve the shape stability of the upper.

The spunbonded nonwoven fabric interposed in the middle of the fiber web lamination is a spunbonded long fiber nonwoven fabric, and can maintain the shape stability of the nonwoven fabric by reinforcing the fiber web. Spunbond nonwoven fabric has a thickness of 0.15~0.60mm and a weight of 20~100g/㎡. The tensile strength is 2.5~15.0kg/2.54cm in the warp direction and 2.0~10.0kg/2.54cm in the weft direction, and the elongation is 20% in the warp direction. It can have physical properties of ~100%, and 20~100% in the weft direction.

Nonwoven fabrics made from non-woven fabric reinforced with 5 to 10 weight percent of spunbond nonwoven fabric and 90 to 95 percent by weight of waste fiber, relative to the total weight of the non-woven fabric, have high shape stability and can increase porosity and bulkiness at the same time. At this time, if the content of the spunbond nonwoven fabric relative to the total weight of the nonwoven fabric is less than 5% by weight, the reinforcing properties are weak, and if it exceeds 10% by weight, the physical properties of the nonwoven fabric are affected and the rebound elasticity is lowered.

The needle punching process, which creates non-woven fabric by binding and lamination of fiber web and sponbond non-woven fabric, requires changing the needle punching process conditions of general non-woven fabric in order to maintain the porosity of the non-woven fabric and the hollowness of the hollow fiber. It is recommended to reduce the number of needles on the needle plate by 20 to 40%, arrange them in a zigzag shape, and punch the depth of needles to a depth of 50 to 70% of the existing needle depth. This is because the existing needle punching process produces dense mechanical interlocking of the fibers that make up the non-woven fabric, which increases the density of the non-woven fabric and reduces its thickness, resulting in a decrease in durability such as rebound elasticity.

Needle-punched fiber webs have the advantage of preventing curling and improving planar smoothness, softness, and tensile strength through shrinkage and compression processes. In the shrinking process, the needle-punched fibrous web is contracted by impregnating it in an impregnation solution containing 2 to 10% by weight of polyvinyl alcohol, 1 to 3% by weight of softener, and the balance of purified water at a temperature of 60 to 85 ° C. Preferably, the impregnating liquid may contain 3 to 4% by weight of polyvinyl alcohol, 2 to 3% by weight of softener, and 93 to 95% by weight of purified water.

When the fibrous web is impregnated with an impregnating liquid of the above-described composition and shrunk, the polyvinyl alcohol contained in the impregnating liquid imparts planar smoothness and softness to the fibrous web, improving work efficiency, and improving the shape of the final nonwoven fabric manufactured. Stability can be improved. If the content of polyvinyl alcohol is less than 2% by weight, the effect of imparting smoothness and softness to the fiber web may be minimal. Conversely, if it exceeds 10% by weight, the cost of the manufacturing process may increase, and a film may be formed on the impregnation liquid. This may result in reduced workability.

Softeners can soften the fiber web and improve elongation and tear strength. If the softener content is less than 1% by weight, the effect of providing softness to the fiber web may be minimal. Conversely, if it exceeds 3% by weight, the surface of the fiber web is too soft, resulting in poor workability such as winding and poor elongation and tear strength. may deteriorate. At this time, the softener may be one or more types selected from the group consisting of silicone softeners and general softeners, and may preferably be a silicone softener. When a silicone softener is used, it has the effect of improving the tear strength and elongation of the final manufactured nonwoven fabric more than that of a general softener.

The fiber web that has gone through the shrinkage process is dehydrated and dried at high temperatures to remove moisture, then passed through a compressor at 100 to 170°C and compressed. The compressed fiber web is made into non-woven fabric by passing between calendar rolls maintained at regular intervals.

By spraying and depositing a resin composition of water-based polyester resin, water-based acrylic resin, or water-based polyurethane resin mixed with purified water on the manufactured non-woven fabric, the non-woven fabric has elastic resilience and elongation more suitable as a shoe upper, and has shape stability. You can have it. At this time, the resin of the resin composition may be mixed at 5 to 15% by weight, and purified water may be mixed at 85 to 95% by weight. If the resin content relative to the total weight of the resin composition is less than 5% by weight, the elastic repulsion force and physical properties decrease, and if it exceeds 15% by weight, there is no significant change in the elastic repulsion force and physical properties.

During the spraying process of the resin composition, the liquid resin composition is sprayed in a fan-shaped spray pattern through a fine nozzle on the top of the non-woven fabric, and at the same time, compressed air is sprayed with an air gun so that the resin composition can be uniformly applied and penetrated into the non-woven fabric. This allows the resin to be densely deposited and applied between the pores between the fibers of the non-woven fabric, improving excellent resilience, durability, and shape stability.

After manufacturing the non-woven fabric 12 using the waste fiber 11 made by pulverizing the fabric scrap, the non-woven fabric can be manufactured into the recycled upper 10 through a known shoe upper manufacturing process such as cutting and skiving. .

Meanwhile, the recycled shoe sole (20) can be made by mixing the foam scrap (21) obtained by rapid freeze-grinding the foam scrap generated in the shoe sole manufacturing process with a foam resin and foam molding.

The process of grinding the foam scrap is the same or similar to the process of grinding the fabric scrap for the recycled upper 10 described above. That is, the foam scrap is cut to a predetermined length using a cutter mill equipment, then placed in a cryogenic chamber supplied with a cryogenic fluid such as liquid nitrogen, rapidly frozen, and pulverized with a grinder in the cryogenic chamber to approximately 0.1 Foam grinds 21 are prepared to a size of ~1 mm (average diameter).

Then, the pulverized foam 21 is mixed with foam resin and foaming additives suitable for the type of shoe sole, such as insole, midsole, and outsole, and foam molded to produce insole and midsole. , outsole can be manufactured. For example, the pulverized foam 21 is mixed with EVA (Ethylene Vinyl Acetate) resin and polyethylene (PE) resin as foaming resins, and crosslinking accelerator, foaming agent, and crosslinking agent as foaming additives in predetermined amounts to form a foam mixture. , the foam mixture is mixed in a kneader, the mixture that has passed through the kneader is dispersed and transformed into a sheet form through roll processing, cut into appropriate sizes, and then the cut sheet-shaped material is placed in a press and heated for a certain period of time to foam it. Insole, midsole, and outsole can be manufactured.

When preparing the foam mixture, it is preferable to mix 20 to 60 parts by weight of pulverized foam with respect to 100 parts by weight of the foam resin.

When manufacturing the recycled shoe sole 20 by mixing the pulverized foam 21 with foam resin and foaming additives, the waste fibers used to manufacture the nonwoven fabric 12 for the recycled upper 10 are mixed with foam resin and additives. By mixing them together, the recycled shoe sole 20 can be produced. In this case, the waste fiber fills the voids of the recycled shoe sole 20 and functions as a reinforcing material, thereby improving the strength and durability of the recycled shoe sole 20.

In this way, the upcycling shoes of the present invention rapidly freeze and crush fabric scraps and foam scraps generated during the manufacturing process of shoes or clothing to obtain waste fibers and foam pulverized material (21), and use the waste fibers to produce a material suitable for shoe uppers. In addition to manufacturing shoe uppers by making non-woven fabric, shoe soles can be foam molded using pulverized foam (21).

Therefore, by manufacturing the entire shoe from recycled materials, the manufacturing cost can be lowered and the process can be simplified, while sufficient physical properties can be obtained compared to raw materials.

In the above, the present invention has been described in detail with reference to examples, but those skilled in the art will be able to make various substitutions, additions, and modifications without departing from the technical spirit described above. It is natural, and such modified embodiments should also be understood as falling within the scope of protection of the present invention as defined by the patent claims attached below.

10: Recycled upper 11: Waste fiber
12: Non-woven fabric 20: Recycled shoe sole
21: foam pulverized material

Claims (6)

Recycled upper made of non-woven fabric manufactured using waste fibers with a length of 0.3 to 10 mm obtained by rapidly freezing and pulverizing fabric scraps generated in the shoe upper or clothing manufacturing process; and,
A recycled shoe sole that is foam-molded by mixing foam scrap obtained by rapid freeze-grinding of foam scrap generated in the shoe sole manufacturing process with a foam resin and attached to the lower end of the recycled upper;
Including,
The recycled shoe sole is mixed with waste fibers used to manufacture the non-woven fabric that makes up the recycled upper,
The nonwoven fabric forming the recycled upper is laminated by binding a sponbond nonwoven fabric to a fiber web made using the waste fiber, and an impregnating solution containing 2 to 10% by weight of polyvinyl alcohol, 1 to 3% by weight of softener, and the balance purified water. After being impregnated and shrunk, an upcycling shoe is deposited with a resin composition obtained by mixing any one of water-based polyester resin, water-based acrylic resin, and water-based polyurethane resin with purified water. delete delete A method of manufacturing upcycling shoes according to claim 1,
(S1) rapidly freezing fabric scraps generated in the shoe upper or clothing manufacturing process and then pulverizing them to produce waste fibers with a length of 0.3 to 10 mm;
(S2) manufacturing a nonwoven fabric using the waste fiber produced in step (S1);
(S3) manufacturing a recycled upper by cutting the nonwoven fabric prepared in step (S2);
(S4) producing pulverized foam by rapidly freezing and pulverizing foam resin scraps generated during the shoe sole manufacturing process;
(S5) mixing the pulverized foam prepared in step (S4) with a foam resin and foam molding to produce a recycled shoe sole; and,
(S6) bonding the lower part of the recycled upper made in step (S3) with the recycled shoe sole made in step (S5);
Including,
When mixing the pulverized foam with the foam resin in step (S5), the waste fibers prepared in step (S1) are mixed together to produce a recycled shoe sole,
In the step (S2), a mixing process in which waste fibers are put into a hopper and mixed, a carding process in which the mixed fibers are arranged as if combing after going through the blending process, and the size and thickness of the listed fibers are adjusted. A process of forming (lapping) a fiber web by spreading and overlapping it to form a fiber web and interposing spunbonded non-woven fabric as a reinforcement material between the fiber webs. Needle punching is a process of binding and laminating the fiber web and spunbonded non-woven fabric. ) process, a shrinking process in which the needle-punched fiber web is impregnated with an impregnation solution containing 2-10% by weight of polyvinyl alcohol, 1-3% by weight of softener, and the balance purified water, and then shrunk, the shrunken fiber web is 100-170% Non-woven fabric is made through a compression process of compressing at a temperature of ℃, and a calendering process of calendering the compressed fiber web to produce non-woven fabric, and the non-woven fabric is mixed with one of water-based polyester resin, water-based acrylic resin, and water-based polyurethane resin. A method of manufacturing upcycling shoes that produces a non-woven fabric by spraying and drying a resin composition mixed with purified water. delete delete

Images