Hot melt adhesive for shoe material as well as preparation method and application method of hot melt adhesive

Abstract

The invention provides a hot melt adhesive for shoe materials as well as a preparation method and an application method of the hot melt adhesive. The hot melt adhesive comprises the following components in percentage by mass: 35-45% of PET (Polyethylene Terephthalate); 25 to 35 parts of PC; 28%-35% of polyurethane; and 10%-12% of a functional auxiliary agent. According to the manufacturing method, PET, PC and polyurethane can be obtained by recycling waste plastic bottles and the like and are crushed into powder, so that the effect of recycling wastes is achieved, and environmental protection is facilitated. When the hot melt adhesive is manufactured, the PC powder is spread and pressed, the PET powder is spread and pressed, and the polyurethane powder is spread and pressed in three steps in sequence, so that the PC layer, the PET layer and the polyurethane layer which are stacked in sequence are formed through shaping, and then the PC layer, the PET layer and the polyurethane layer are condensed through high temperature to form the hot melt adhesive. And moreover, the shoe material has the characteristics of high hardness, strong resilience and the like and is not easy to deform, and two parts of the shoe material can be firmly bonded and fixed, so that the shoe material has better practicability.

Description

Technical Field

[0001] The invention relates to the field of hot melt adhesives, in particular to a hot melt adhesive for shoe materials and a preparation method and an application method thereof. Background Art

[0002] Hot melt adhesive is a plastic adhesive. Its physical state changes with temperature within a certain temperature range, but its chemical properties remain unchanged. It is non-toxic and tasteless, and is an environmentally friendly chemical product. It is favored by shoe manufacturers for its simple production process, high bonding strength, and fast speed.

[0003] Hot melt adhesives currently used in the field of shoe materials are mainly formed by heating a mixture of synthetic rubber, resin, and rubber oil. When bonding shoe parts, it is often difficult to firmly bond the two parts due to their soft and easily deformable state, resulting in insufficient bonding strength and easy debonding. Summary of the invention

[0004] In view of the deficiencies of the above background technology, the present invention provides a hot melt adhesive for shoe materials and a preparation method and an application method thereof.

[0005] The present invention adopts the following technical solution: In a first aspect, the present invention provides a hot melt adhesive for shoe materials, characterized in that the hot melt adhesive comprises the following components in percentage by mass: PET 35%~45%; PC 25%~35%; Polyurethane 28%-35%; Functional additives 10% to 12%; Wherein, the functional additives include bactericide, anti-yellowing agent, talcum powder, straw and starch.

[0006] In a second aspect, the present invention provides a method for preparing a hot melt adhesive for shoe materials, characterized in that the method comprises the following steps: Collecting wastes formed by PET, PC, and polyurethane, respectively, crushing each waste into powder, respectively adding functional additives, and obtaining PET powder, PC powder, and polyurethane powder; Spreading the PC powder evenly on the platform and flattening it to form a PC layer; The PET powder is evenly spread on the PC layer and then flattened to form a PET layer; Evenly spreading the polyurethane powder on the PET layer, and then flattening it to form a polyurethane layer; The PC layer, the PET layer and the polyurethane layer are pressed together to obtain a sheet-like hot melt adhesive.

[0007] In a feasible implementation of the second aspect, the PC layer, the PET layer and the polyurethane layer are heated at a temperature of 100 to 110° C., and a layer of polyurethane powder is sprayed on the surface of the polyurethane layer, and then the PC layer, the PET layer and the polyurethane layer are pressed to obtain a sheet of hot melt adhesive.

[0008] In a feasible implementation manner of the second aspect, a base cloth is laid flat on a platform, and then the PC powder is evenly spread on the base cloth.

[0009] In a feasible implementation manner of the second aspect, the PC powder, the PET powder and the polyurethane powder are all subjected to a heat treatment during the flattening process.

[0010] In a third aspect, the present invention provides a method for applying a hot melt adhesive, characterized in that the method comprises the following steps: Placing the hot melt adhesive in a temperature environment of 50 to 55° C. to soften the hot melt adhesive; Place the hot melt adhesive between the two parts of the shoe material that need to be bonded, and apply pressure to the two objects to press and bond the two objects into shape.

[0011] From the above description of the structure of the present invention, it can be seen that compared with the prior art, the present invention has the following advantages: the PET, PC and polyurethane of the present invention can be obtained by recycling discarded plastic bottles and crushing them into powder, thereby achieving the effect of waste recycling, which is beneficial to environmental protection. During production, the PC powder is spread and pressed in turn, the PET powder is spread and pressed in turn, and the polyurethane powder is spread and pressed in turn in three steps, so as to form a PC layer, a PET layer and a polyurethane layer stacked in turn, and then the PC layer, the PET layer and the polyurethane layer are condensed at high temperature to form a hot melt adhesive. The hot melt adhesive formed by this method is thin and light as a whole, and has the characteristics of high hardness, strong resilience and other characteristics that are not easy to deform. It can firmly bond and fix two parts, so it has better practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the cross-sectional structure of the hot melt adhesive of the present invention. DETAILED DESCRIPTION

[0013] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0014] In the present application, directional terms such as "upper" and "lower" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they may change accordingly according to the change of the orientation of the components in the drawings.

[0015] The present invention discloses a hot melt adhesive for shoe materials and a preparation method and application method thereof. The hot melt adhesive comprises the following components in mass percentage: PET 35% to 45%; PC 25 to 35; polyurethane 28% to 35%; functional additives 10% to 12%. Preferably, the mass percentages of the components of the hot melt adhesive are PET 40%, PC 20%, polyurethane 30% and functional additives 10%.

[0016] As shown in the accompanying drawings, the functional additives include a sterilizer, an anti-yellowing agent, talcum powder, straw, starch, resin and thickener. Among them, talcum powder is used as a filler, and talcum powder and straw are used to improve the tensile strength, compressive strength and flexural strength of the hot melt adhesive. Starch is used to form the adhesion of the hot melt adhesive. Resin and thickener are used to improve the adhesion of the hot melt adhesive. In addition, the sterilizer can be a nano-silver antibacterial powder, the anti-yellowing agent can be an organic tin anti-yellowing promoter, and the thickener can be an alkali-swellable associative thickener modified with a hydrophilic group, which helps the pressed hot melt adhesive to maintain the solid structure of the sheet.

[0017] The method for preparing the hot melt adhesive of the present invention comprises the following steps: Collecting wastes formed by PET, PC, and polyurethane, respectively, crushing each waste into powder, respectively adding functional additives, and obtaining PET powder, PC powder, and polyurethane powder, wherein the ratio of PET to the functional additive is preferably 10:1, the ratio of PC to the functional additive is preferably 8:1, and the ratio of polyurethane to the functional additive is preferably 10:1; The PC powder is evenly spread on the platform, and then the PC powder is flattened. During the flattening process, the PC powder is heated at a temperature of 210 to 220° C. for 40 to 50 seconds to condense the PC powder to form a PC layer 1; The PET powder is evenly spread on the PC layer 1, and then the PET powder is flattened. During the flattening process, the PET powder is heated at a temperature of 150 to 170° C. for 40 to 50 seconds so that the PET powder is flattened and condensed to form a PET layer 2; The polyurethane powder is evenly spread on the PET layer 2, and then the polyurethane powder is flattened. During the flattening process, the polyurethane powder is heated at a temperature of 240 to 260° C. for 40 to 50 seconds so that the polyurethane powder is flattened and condensed to form a polyurethane layer 3; The PC layer 1, the PET layer 2 and the polyurethane layer 3 are pressed and heated at a temperature of 230 to 250° C. for 20 to 25 seconds to condense the PC layer 1, the PET layer 2 and the polyurethane layer 3 to form an integrated hot melt adhesive sheet; The hot melt adhesive of the present invention can be obtained by spraying a layer of polyurethane powder on the surface of the hot melt adhesive sheet formed by the PC layer 1, the PET layer 2 and the polyurethane layer 3, and then pressing the hot melt adhesive sheet to fix the polyurethane powder on the surface of the hot melt adhesive sheet.

[0018] In addition, waste generated by PET, PC, and polyurethane can be obtained by recycling discarded plastic bottles, etc., thereby achieving the effect of waste recycling and benefiting environmental protection.

[0019] In addition, before spreading the PC powder on the platform, the base cloth 4 can be spread flat on the platform, and then the PC powder can be spread on the base cloth 4 to form a hot melt adhesive structure in which a PC layer 1, a PET layer 2 and a polyurethane layer 3 are sequentially formed on the base cloth 4. In this structure, the base cloth 4 can further improve the hardness and tensile strength of the hot melt adhesive.

[0020] It is worth mentioning that the above-mentioned platform is a horizontal surface with a heating device at the bottom. A pressure plate driven by a hydraulic cylinder is arranged above the platform. The flattening action is achieved by applying pressure by pressing down on the pressure plate. A heating device can be arranged inside the pressure plate. The heating device can be an electric heating tube that converts electrical energy into thermal energy, so that the pressure plate can flatten the powder while heating the powder and other materials above the platform to a specified temperature.

[0021] The application method of the hot melt adhesive of the present invention comprises the following steps: Place the hot melt adhesive in a temperature environment of 50-55°C to soften the hot melt adhesive; The heated and softened hot melt adhesive is placed between the two parts of the shoe material that need to be bonded, and pressure is applied to the two objects so that the two objects press the hot melt adhesive together, thereby bonding the two objects into shape through the hot melt adhesive. This processing method is simple and effective.

[0022] In summary, the PET, PC and polyurethane of the present invention can recycle discarded plastic bottles and the like, and crush them into powder, thereby achieving the effect of waste recycling, which is beneficial to environmental protection. During production, the PC powder is sequentially spread and pressed, the PET powder is spread and pressed, and the polyurethane powder is spread and pressed in three steps, so as to form a PC layer 1, a PET layer 2 and a polyurethane layer 3 stacked in sequence, and then the PC layer 1, the PET layer 2 and the polyurethane layer 3 are condensed at high temperature to form a hot melt adhesive. The hot melt adhesive formed by this method is thin and light as a whole, and has the characteristics of high hardness, strong resilience and the like, which is not easy to deform. It can firmly bond and fix two parts, so it has better practicality and is conducive to popularization and application.

[0023] The above is only a specific implementation of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial changes to the present invention using this concept shall be deemed as an infringement of the protection scope of the present invention.

Claims

1. A hot melt adhesive for shoe materials, characterized in that: The hot melt adhesive comprises the following components in percentage by mass: PET 35%~45%; PC 25%~35%; Polyurethane 28%-35%; Functional additives 10% to 12%; Wherein, the functional additives include bactericide, anti-yellowing agent, talcum powder, straw and starch.

2. A method for making a hot melt adhesive for shoe materials according to claim 1, characterized in that: The preparation method comprises the following steps: Collecting wastes formed by PET, PC, and polyurethane, respectively, crushing each waste into powder, respectively adding functional additives, and obtaining PET powder, PC powder, and polyurethane powder; Spreading the PC powder evenly on the platform and flattening it to form a PC layer; The PET powder is evenly spread on the PC layer and then flattened to form a PET layer; Evenly spreading the polyurethane powder on the PET layer, and then flattening it to form a polyurethane layer; The PC layer, the PET layer and the polyurethane layer are pressed together to obtain a sheet-like hot melt adhesive.

3. A hot melt adhesive for shoe materials and a method for making the same as claimed in claim 2, characterized in that: The PC layer, the PET layer and the polyurethane layer are heated at a temperature of 100 to 110° C., a layer of polyurethane powder is sprayed on the surface of the polyurethane layer, and then the PC layer, the PET layer and the polyurethane layer are pressed to obtain a sheet-like hot melt adhesive.

4. A hot melt adhesive for shoe materials and a method for making the same as claimed in claim 2, characterized in that: Lay a base cloth flat on the platform, and then evenly spread the PC powder on the base cloth.

5. The hot melt adhesive for shoe materials and the method for making the hot melt adhesive as claimed in claim 2, characterized in that: The PC powder, the PET powder and the polyurethane powder are all subjected to a heating treatment during the flattening process.

6. A method for applying the hot melt adhesive according to claim 1, characterized in that: The application method comprises the following steps: Placing the hot melt adhesive in a temperature environment of 50 to 55° C. to soften the hot melt adhesive; Place the hot melt adhesive between the two parts of the shoe material that need to be bonded, and apply pressure to the two objects to press and bond the two objects into shape.

Images