Manufacturing method of cool-feeling non-woven fabric with phase-change heat absorption coating

Abstract

The invention discloses a manufacturing method of cool non-woven fabric with a phase change heat absorption coating, and belongs to the technical field of non-woven fabric, the manufacturing method comprises the following steps: S1, a skin layer component and a bridging component are spun to obtain bridging fiber with a skin-core structure, and the structure of the bridging fiber is formed by wrapping the bridging component with the skin layer component; s2, respectively paving the bridging fibers and the main fibers to form a bridging fiber net and a main fiber net, and reinforcing and forming to obtain a non-woven fabric base material; wherein the melting temperature of each component in the non-woven fabric base material is as follows: the main fiber > the bridging component > the skin layer component; s3, covering the surface of the bridging fiber net of the non-woven fabric base material with a phase change coating through heat transfer printing; in the heat transfer printing process, the core layer component and a curing agent in the phase change coating are subjected to a cross-linking curing reaction; s4, drying the phase change coating on the surface of the non-woven fabric base material to obtain the cool non-woven fabric; the adhesive force of the phase change coating and the non-woven fabric base material in the cool-feeling non-woven fabric can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of non-woven fabrics, and specifically relates to a method for manufacturing a cool-sensation non-woven fabric with a phase-change heat-absorbing coating. Background Art

[0002] Non-woven fabrics are widely used in disposable hygiene products such as disposable masks, medical protective clothing, diapers, sanitary napkins, etc. Most of these products need to be in direct contact with the human body. Users are prone to obvious stuffy and hot feelings when using these products in hot weather. To solve the defects of these products, the current common practice is to combine non-woven fabrics with materials that can produce a cool sensation, such as phase-change materials, to make cool-sensation non-woven fabrics. The cool-sensation non-woven fabric usually mixes the phase-change material into the coating and then coats it on the surface of the non-woven fabric, so that a heat-absorbing and cool-sensation coating is formed on the surface of the cool-sensation non-woven fabric; however, due to the fact that the non-woven fabric is composed of randomly cross-linked fibers, there are a large number of pores and unevenness on its surface, resulting in difficult uniform coverage of the coating, and due to poor compatibility between the non-woven fabric fibers and the coating, etc., ultimately the adhesion of the coating on the surface of the non-woven fabric is poor, making the coating prone to falling off during use.

[0003] Based on the above situation, Chinese Patent with Publication (Announcement) No. CN112726199B discloses a cool-sensation skin-friendly non-woven fabric and its preparation method. The cool-sensation skin-friendly non-woven fabric is made from the following raw materials: modified polypropylene, jade masterbatch, xylitol masterbatch, polypropylene; the preparation method of the cool-sensation skin-friendly non-woven fabric includes the following steps: forming a cool-sensation reinforced non-woven fabric by subjecting the raw materials to stock preparation, feeding, melt extrusion, metering, spinning, drawing, web laying, and calender fixing; preparing a hydrophilic cool-sensation oil agent / hydrophobic cool-sensation oil agent by mixing xylitol, mint extract, ice-sensation silicone oil, hydrophilic oil agent / wetting agent, microcapsule phase-change material, and water, and applying the hydrophilic cool-sensation oil agent / hydrophobic cool-sensation oil agent onto the cool-sensation reinforced non-woven fabric by means of coating, padding, or spraying and drying to obtain the cool-sensation skin-friendly non-woven fabric.

[0004] The above patent document discloses a cool-sensation non-woven fabric with a cool-sensation coating formed by a hydrophilic cool-sensation oil agent or a hydrophobic cool-sensation oil agent on its surface. The cool-sensation coating is attached to the surface of the non-woven fabric by means of coating, padding, or spraying. After drying, the coating is mainly fixed to the non-woven fabric by being embedded inside the non-woven fabric and embracing the fibers, but due to the relatively smooth surface of the fibers that make up the non-woven fabric, the coating material embracing the fiber surface is prone to sliding along the fiber extension direction under external force, and the coating on the surface of the cool-sensation non-woven fabric is prone to falling off under external force, and the adhesion of the surface coating of the cool-sensation non-woven fabric is poor. Therefore, there is still room for improvement in this cool-sensation non-woven fabric. Summary of the Invention

[0005] In view of the technical defects in the background art, the present invention provides a method for manufacturing a cool-sensing non-woven fabric with a phase-change heat-absorbing coating, which solves the above-mentioned technical problems and meets the actual needs. The specific technical solutions are as follows: A method for manufacturing a cool-sensing non-woven fabric with a phase-change heat-absorbing coating, comprising the following steps: S1. Spinning the cortical component and the bridging component through a bicomponent melt spinning machine to obtain a core-sheath structured bridging fiber, the structure of the bridging fiber being composed of the cortical component wrapping the bridging component; S2. After opening and impurity removal, the bridging fiber and the main fiber are respectively laid to form a bridging fiber web and a main fiber web. After covering the bridging fiber web on the surface of the main fiber web, it is heated and solidified to form a non-woven fabric substrate; Among them, the melting temperatures of the components in the non-woven fabric substrate are: main fiber > bridging component > cortical component; S3. Mixing and stirring the phase-change microcapsules, film-forming agent, solvent, curing agent, and coating auxiliary agent evenly to obtain a phase-change coating, and covering the phase-change coating on the surface of the bridging fiber web of the non-woven fabric substrate through heat transfer printing; During the heat transfer printing process, both the cortical component and the core layer component are heated to the molten state, and the core layer component and the curing agent in the phase-change coating undergo a cross-linking curing reaction; S4. After drying, the phase-change coating forms a phase-change coating on the surface of the non-woven fabric substrate, and the phase-change coating and the non-woven fabric substrate together form a cool-sensing non-woven fabric.

[0006] As a further technical solution of the present invention, the bridging component includes the following components by mass percentage: bisphenol F type epoxy resin 86% - 92%, nano-silica 5% - 10%, dispersant 1% - 3%, first antioxidant 0.5% - 1%.

[0007] As a further technical solution of the present invention, the coating auxiliary agent includes a promoter and a wetting agent, and the phase-change coating includes the following components by mass percentage: phase-change microcapsules 30% - 50%, film-forming agent 30% - 50%, solvent 5% - 15%, curing agent 5% - 10%, promoter 1% - 2%, wetting agent 0.2% - 0.5%.

[0008] As a further technical solution of the present invention, the curing agent is in granular form and is composed of dicyandiamide inside wrapped by a thermoplastic polymer on the surface, and the mass ratio of the thermoplastic polymer to dicyandiamide in the curing agent is 1:(1 - 3).

[0009] As a further technical solution of the present invention, the phase-change microcapsules are composed of a phase-change material inside wrapped by a polyurethane resin on the surface, the phase-change temperature of the phase-change material is 20 - 30 °C, and the mass ratio of the polyurethane resin to the phase-change material in the phase-change microcapsules is 1:(1 - 2).

[0010] As a further technical solution of the present invention, the cortical composition comprises the following components by mass percentage: 90% - 94% of polyethylene resin, 5% - 8% of maleic anhydride grafted low density polyethylene, 0.5% - 2% of lubricant, and 0.2% - 1% of a second antioxidant; The polyethylene resin includes linear low density polyethylene and low density polyethylene, and the mass ratio of the linear low density polyethylene to the low density polyethylene is 1:1.

[0011] As a further technical solution of the present invention, the main fiber is selected from one of polypropylene fiber and polyester fiber.

[0012] As a further technical solution of the present invention, the mass ratio of the cortical component to the bridging component in the bridging fiber is 1:(1 - 2).

[0013] As a further technical solution of the present invention, the gram weight of the non-woven fabric substrate is 20 - 100 gsm, and the mass ratio of the bridging fiber network to the main fiber network in the non-woven fabric substrate is 1:(3 - 5).

[0014] As a further technical solution of the present invention, the heating temperature during the reinforcement and shaping of the non-woven fabric substrate is 115 - 120 °C; the heating temperature during the thermal transfer printing of the phase change coating is 130 - 150 °C.

[0015] The beneficial effects of the present invention are as follows: The cool-sensation non-woven fabric of the present invention is composed of a non-woven fabric substrate and a phase change coating on the surface. The phase change coating conducts thermal management through the phase change material in the internal phase change microcapsules. When a user comes into contact with the cool-sensation non-woven fabric, a sense of coolness will be felt. In the non-woven fabric substrate, the bridging fiber network and the main fiber network are hot-rolled and reinforced through the melting temperature difference between the cortical component and the main fiber, and the structure of the bridging component is kept intact. When the phase change coating is subsequently coated on the surface of the bridging fiber network by thermal transfer printing, the curing agent releases dicyandiamide and undergoes a cross-linking curing reaction with the epoxy resin in the bridging component, improving the firmness of the cured phase change coating attached to the surface of the non-woven fabric substrate, thereby enhancing the safety of the cool-sensation non-woven fabric and the durability of thermal management. Specific Embodiments

[0016] The following describes the embodiments of the present invention in conjunction with relevant examples. The embodiments of the present invention are not limited to the following examples, and the relevant necessary components involved in the present invention should be regarded as well-known technologies in the technical field, which can be known and mastered by those skilled in the technical field.

[0017] A manufacturing method of a cool-sensation non-woven fabric with a phase change endothermic coating, comprising the following steps: S1. The cortical component and the bridging component are spun by a bicomponent melt spinning machine to obtain a core - sheath structured bridging fiber, and the structure of the bridging fiber is composed of the cortical component wrapping the bridging component; S2. The bridging fiber and the main fiber are respectively laid after being opened and impurity - removed to form a bridging fiber web and a main fiber web. After covering the main fiber web with the bridging fiber web, it is heated and solidified to form a non - woven fabric substrate; Among them, the melting temperatures of the components in the non - woven fabric substrate are: main fiber > bridging component > cortical component; S3. The phase - change microcapsules, film - forming agent, solvent, curing agent, and coating auxiliary are mixed and stirred evenly to obtain a phase - change coating, and the phase - change coating is covered on the surface of the bridging fiber web of the non - woven fabric substrate through heat transfer printing; During the heat transfer printing process, both the cortical component and the core component are heated to the molten state, and the core component undergoes a cross - linking curing reaction with the curing agent in the phase - change coating; S4. The phase - change coating forms a phase - change coating on the surface of the non - woven fabric substrate after drying, and the phase - change coating and the non - woven fabric substrate together form a cool - feeling non - woven fabric.

[0018] In step S1 of the present invention, the cortical composition includes the following components by mass percentage: 90% - 94% of polyethylene resin, 5% - 8% of maleic anhydride - grafted low - density polyethylene, 0.5% - 2% of lubricant, and 0.2% - 1% of the second antioxidant; the polyethylene resin includes linear low - density polyethylene and low - density polyethylene, and the mass ratio of linear low - density polyethylene to low - density polyethylene is 1:1; the cortical component is mainly composed of polyethylene resin. During the spinning process, the polyethylene resin is mainly used to wrap the bridging component and form the bridging fiber, and the added maleic anhydride - grafted low - density polyethylene can be used as a compatibilizer, which is beneficial to improving the interfacial bonding force between the bridging fiber and the main fiber, thereby improving the strength of the non - woven fabric substrate; the lubricant is preferably calcium stearate, and calcium stearate acts as a lubricant in the molten polyethylene resin, which can reduce the friction between polymer molecular chains and improve the fluidity of the melt during extrusion molding, being beneficial to improving the smoothness and uniformity of the fiber surface; the second antioxidant is preferably antioxidant 1010, and antioxidant 1010 can improve the thermal stability of the polyethylene resin during hot - processing such as the solidification and shaping of the non - woven fabric substrate and the heat transfer printing of the phase - change coating.

[0019] Further, the bridging component comprises the following components by mass percentage: 86% - 92% of bisphenol F type epoxy resin, 5% - 10% of nano-silica, 1% - 3% of dispersant, and 0.5% - 1% of the first antioxidant. The bisphenol F type epoxy resin, as the main component of the bridging component, is mainly used to undergo crosslinking and curing reaction with the curing agent in the phase change coating. The nano-silica serves as a heat-resistant filler in the bisphenol F type epoxy resin to increase the heat distortion temperature of the bisphenol F type epoxy resin, enabling the bridging component to maintain structural stability during the reinforcement and molding process of the non-woven fabric substrate and avoiding premature leakage outside the cortical component. The dispersant is preferably polyethylene wax, which is beneficial to improving the dispersion uniformity of nano-silica in the bisphenol F type epoxy resin. Additionally, the first antioxidant is preferably a compound of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:2 to improve the thermal stability of the bridging component during hot processing such as the reinforcement and molding of the non-woven fabric substrate and the thermal transfer printing of the phase change coating. Moreover, the mass ratio of the cortical component to the bridging component in the bridging fiber is 1:(1 - 2), preferably 1:1.5.

[0020] Further, the polyethylene resin is composed of linear low-density polyethylene and low-density polyethylene. The low-density polyethylene can reduce the melting temperature and the fluidity after melting of the cortical component. During the thermal transfer printing process of the phase change coating, the cortical component on the surface of the bridging fiber is heated to the molten state, making it easier to expose the internal bridging component, so that dicyandiamide will contact the epoxy resin and rapidly undergo crosslinking and curing reaction under the action of the accelerator, improving the bonding strength between the phase change coating and the non-woven fabric.

[0021] In step S2 of the present invention, the main fiber is selected from one of polypropylene fiber and polyester fiber. After the bridging fiber and the main fiber are opened and cleaned, the two-component air-laying technology is used to lay them separately to form a bridging fiber web and a main fiber web, and the mass ratio of the bridging fiber web to the main fiber web is maintained at 1:(3 - 5), preferably 1:4. After covering the bridging fiber web on the surface of the main fiber web, the bridging fiber web and the main fiber web are bonded and fixed to form a non-woven fabric substrate by hot rolling reinforcement. The gram weight of the non-woven fabric substrate is 20 - 100 gsm. During the reinforcement and molding process of the non-woven fabric substrate, the heating temperature is 115 - 120 °C. This temperature can heat the cortical component on the surface of the bridging fiber to the molten state and serve as the binder between the bridging fiber web and the main fiber web, bonding and fixing the bridging fiber web and the main fiber web to form a non-woven fabric substrate. The non-woven fabric substrate can also be hot-rolled into shape by the method of sectional hot rolling, that is, the hot rolling temperature on the side close to the bridging fiber web is 115 - 120 °C, while the hot rolling temperature on the side close to the main fiber web is slightly higher than the melting temperature of the main fiber. Sectional hot rolling can improve the bonding strength inside the main fiber web, thereby improving the strength of the non-woven fabric substrate. Additionally, after the non-woven fabric substrate is reinforced and molded, it can be subjected to corona treatment to increase its surface energy, which is beneficial to improving the adhesion of the phase change coating.

[0022] In step S3 of the present invention, the coating aids include a promoter and a wetting agent. The phase change coating comprises the following components by mass percentage: 30% - 50% of phase change microcapsules, 30% - 50% of film-forming agent, 5% - 15% of solvent, 5% - 10% of curing agent, 1% - 2% of promoter, and 0.2% - 0.5% of wetting agent; wherein, the phase change microcapsules are composed of a polyurethane resin on the surface wrapping a phase change material inside, the phase change temperature of the phase change material is 20 - 30°C, and the mass ratio of the polyurethane resin to the phase change material in the phase change microcapsules is 1:(1 - 2), preferably 1:1.5; the film-forming agent is preferably an aqueous polyurethane resin, the solid content of the aqueous polyurethane resin is about 50%, the solvent is preferably deionized water, and the deionized water is used to adjust the viscosity of the phase change coating and improve the coating performance of the phase change coating; the curing agent is in granular form and is composed of a thermoplastic polymer on the surface wrapping dicyandiamide inside, the thermoplastic polymer is preferably polyethylene wax, the dicyandiamide is preferably LB-A modified dicyandiamide, and the mass ratio of the thermoplastic polymer to the dicyandiamide in the curing agent is 1:(1 - 3), preferably 1:2. The promoter is preferably 2-ethyl-4-methylimidazole, and the promoter is mainly used to promote the crosslinking and curing reaction of dicyandiamide and epoxy resin, reduce the temperature required for the crosslinking and curing reaction, and shorten the time required for the crosslinking and curing reaction; the wetting agent is preferably polyether-modified silicone, and the wetting agent is used to improve the wetting performance of the phase change coating, making it easier for the phase change coating to adhere to the surface of the non-woven fabric substrate.

[0023] Furthermore, during the heat transfer printing process of the phase change coating, the heating temperature is 130 - 150°C. This temperature can heat the cortical component on the surface of the bridging fiber to melting, exposing the internal bridging component, and the bridging component is also heated to be fully softened. The polyethylene wax on the outer shell of the phase change microcapsules in the phase change coating will also be heated to melting, releasing the internal dicyandiamide. The dicyandiamide will contact the epoxy resin and rapidly undergo a crosslinking and curing reaction under the action of the promoter. During the subsequent heat drying process of the phase change coating, the crosslinking and curing reaction can also continue. After the solvent in the phase change coating is completely volatilized, a phase change coating is formed on the surface of the non-woven fabric substrate. The phase change coating undergoes a crosslinking and curing reaction with the epoxy resin in the bridging fiber, and the phase change coating can firmly adhere to the surface of the non-woven fabric substrate. The phase change coating conducts thermal management through the phase change material in the phase change microcapsules. When the user touches the cool-sensation non-woven fabric, they will feel a sense of coolness. Since the phase change coating firmly adheres to the surface of the non-woven fabric substrate and is not easily detached, the coolness performance of the cool-sensation non-woven fabric can be maintained for a longer time, and the user does not need to worry about health problems caused by coating detachment, improving the safety of the cool-sensation non-woven fabric.

[0024] It should be further noted that both the phase change microcapsules and the curing agent are made by common microcapsule encapsulation techniques. In the phase change microcapsules, polyurethane resin is used as the shell material and the phase change material is used as the core material. In the curing agent, polyethylene wax is used as the shell material and dicyandiamide is used as the core material. The phase change microcapsules and the curing agent are preferably made based on the emulsification method. The specific operation is as follows: dissolve the shell material in solvent A to form the outer phase, dissolve the core material in solvent B to form the inner phase, and solvents A and B are immiscible. After mixing the outer phase and the inner phase, add a suitable emulsifier to emulsify it into an emulsion, and the outer phase is the continuous phase and the inner phase is the dispersed phase in the emulsion. Then, through heating, cooling, cross-linking and curing, etc., the shell material in the outer phase is cured and the core material is wrapped inside. Then, after filtration, washing and drying, microcapsules with the core material wrapped by the shell material are obtained.

[0025] In summary, the cool-sensation non-woven fabric of the present invention is composed of a non-woven fabric substrate and a phase change coating on the surface. The phase change coating conducts heat management through the phase change material in the internal phase change microcapsules. When users come into contact with the cool-sensation non-woven fabric, they will feel a sense of coolness. In the non-woven fabric substrate, the bridging fiber network and the main fiber network are hot-rolled and reinforced through the melting temperature difference between the cortical component and the main fiber, and the structure of the bridging component is kept intact. When the phase change coating is subsequently coated on the surface of the bridging fiber network by heat transfer printing, the curing agent releases dicyandiamide and undergoes a cross-linking curing reaction with the epoxy resin in the bridging component, improving the firmness of the cured phase change coating attached to the surface of the non-woven fabric substrate, thereby improving the safety of the cool-sensation non-woven fabric and the durability of heat management.

[0026] The present invention is further described below through examples and comparative examples.

[0027] Example 1

[0028] S1. Spinning the cortical component and the bridging component through a bicomponent melt spinning machine to obtain bridging fibers with a core-shell structure, and the structure of the bridging fibers is composed of the cortical component wrapping the bridging component; Among them, the cortical composition includes the following components by mass percentage: linear low-density polyethylene 45.5%, low-density polyethylene 45.5%, maleic anhydride grafted low-density polyethylene 7%, calcium stearate 1.5%, antioxidant (1010) 0.5%; the bridging component includes the following components by mass percentage: bisphenol F type epoxy resin 89.25%, nano-silica 8%, polyethylene wax 2%, antioxidant (1010) 0.5%, antioxidant (168) 0.25%; the mass ratio of the cortical component to the bridging component is 1:1.5; S2. After opening and impurity removal, the bridging fibers and polypropylene fibers are respectively laid to form a bridging fiber web and a polypropylene fiber web. After covering the polypropylene fiber web with the bridging fiber web, it is heated to 120 °C for reinforcement and molding to obtain a non-woven fabric substrate, and the non-woven fabric substrate is subjected to corona treatment; S3. The phase change microcapsules, waterborne polyurethane resin, deionized water, dicyandiamide microcapsules, 2-ethyl-4-methylimidazole, and polyether-modified silicone are mixed and stirred evenly to obtain a phase change coating. The phase change coating is subjected to heat transfer printing at 145 °C and covered on the surface of the bridging fiber web of the non-woven fabric substrate; Among them, the phase change coating includes the following components by mass percentage: 40% of phase change microcapsules, 40% of waterborne polyurethane resin, 10% of deionized water, 8% of dicyandiamide microcapsules, 1.5% of 2-ethyl-4-methylimidazole, and 0.5% of polyether-modified silicone; the structure of the phase change microcapsules is composed of a polyurethane resin wrapping a phase change material, the phase change temperature of the phase change material is 28 °C, and the structure of the dicyandiamide microcapsules is composed of a polyethylene wax wrapping LB-A modified dicyandiamide; S4. After heat drying at 90 °C on the surface of the non-woven fabric substrate, the phase change coating is cured to form a phase change coating, and the phase change coating and the non-woven fabric substrate together form a cool-sensation non-woven fabric.

[0029] Example 2

[0030] S1. The skin component and the bridging component are spun by a two-component melt spinning machine to obtain a bridging fiber with a core-shell structure. The structure of the bridging fiber is composed of the skin component wrapping the bridging component; Among them, the skin composition includes the following components by mass percentage: 45.5% of linear low-density polyethylene, 45.5% of low-density polyethylene, 7% of maleic anhydride-grafted low-density polyethylene, 1.5% of calcium stearate, and 0.5% of antioxidant (1010); the bridging component includes the following components by mass percentage: 89.25% of bisphenol F-type epoxy resin, 8% of nano-silica, 2% of polyethylene wax, 0.5% of antioxidant (1010), and 0.25% of antioxidant (168); the mass ratio of the skin component to the bridging component is 1:1; S2. After opening and impurity removal, the bridging fibers and polypropylene fibers are respectively laid to form a bridging fiber web and a polypropylene fiber web. After covering the polypropylene fiber web with the bridging fiber web, it is heated to 120 °C for reinforcement and molding to obtain a non-woven fabric substrate, and the non-woven fabric substrate is subjected to corona treatment; S3. The phase change microcapsules, waterborne polyurethane resin, deionized water, dicyandiamide microcapsules, 2-ethyl-4-methylimidazole, and polyether-modified silicone are mixed and stirred evenly to obtain a phase change coating. The phase change coating is subjected to heat transfer printing at 145 °C and covered on the surface of the bridging fiber web of the non-woven fabric substrate; Among them, the phase change coating includes the following components by mass percentage: 42% of phase change microcapsules, 40% of waterborne polyurethane resin, 10.5% of deionized water, 6% of dicyandiamide microcapsules, 1% of 2-ethyl-4-methylimidazole, and 0.5% of polyether-modified silicone; the structure of the phase change microcapsules is composed of a polyurethane resin wrapping a phase change material, the phase change temperature of the phase change material is 28°C, and the structure of the dicyandiamide microcapsules is composed of a polyethylene wax wrapping LB-A modified dicyandiamide; S4. After being thermally dried at 90°C on the surface of the non-woven fabric substrate, the phase change coating is cured to form a phase change coating, and the phase change coating and the non-woven fabric substrate together form a cool-sensation non-woven fabric.

[0031] Example 3

[0032] S1. The cortical component and the bridging component are spun by a two-component melt spinning machine to obtain a core-shell structured bridging fiber, and the structure of the bridging fiber is composed of the cortical component wrapping the bridging component; Among them, the cortical composition includes the following components by mass percentage: 45.5% of linear low-density polyethylene, 45.5% of low-density polyethylene, 7% of maleic anhydride-grafted low-density polyethylene, 1.5% of calcium stearate, and 0.5% of antioxidant (1010); the bridging component includes the following components by mass percentage: 89.25% of bisphenol F-type epoxy resin, 8% of nano-silica, 2% of polyethylene wax, 0.5% of antioxidant (1010), and 0.25% of antioxidant (168); the mass ratio of the cortical component to the bridging component is 1:2; S2. The bridging fiber and the polypropylene fiber are respectively laid after being opened and impurity-removed to form a bridging fiber web and a polypropylene fiber web. After covering the polypropylene fiber web with the bridging fiber web, it is heated to 120°C for reinforcement and molding to obtain a non-woven fabric substrate, and the non-woven fabric substrate is corona-treated; S3. The phase change microcapsules, waterborne polyurethane resin, deionized water, dicyandiamide microcapsules, 2-ethyl-4-methylimidazole, and polyether-modified silicone are mixed and stirred evenly to obtain a phase change coating, and the phase change coating is thermally transferred and printed at 145°C to cover the surface of the bridging fiber web of the non-woven fabric substrate; Among them, the phase change coating includes the following components by mass percentage: 38% of phase change microcapsules, 40% of waterborne polyurethane resin, 9.5% of deionized water, 10% of dicyandiamide microcapsules, 2% of 2-ethyl-4-methylimidazole, and 0.5% of polyether-modified silicone; the structure of the phase change microcapsules is composed of a polyurethane resin wrapping a phase change material, the phase change temperature of the phase change material is 28°C, and the structure of the dicyandiamide microcapsules is composed of a polyethylene wax wrapping LB-A modified dicyandiamide; S4. After being thermally dried at 90°C on the surface of the non-woven fabric substrate, the phase change coating is cured to form a phase change coating, and the phase change coating and the non-woven fabric substrate together form a cool-sensation non-woven fabric.

[0033] Example 4

[0034] S1. The cortical component and the bridging component are spun by a bicomponent melt spinning machine to obtain a core - sheath structured bridging fiber, and the structure of the bridging fiber is composed of the cortical component wrapping the bridging component; Among them, the cortical composition includes the following components by mass percentage: linear low - density polyethylene 45.5%, low - density polyethylene 45.5%, maleic anhydride - grafted low - density polyethylene 7%, calcium stearate 1.5%, antioxidant (1010) 0.5%; the bridging component includes the following components by mass percentage: bisphenol F - type epoxy resin 89.25%, nano - silica 8%, polyethylene wax 2%, antioxidant (1010) 0.5%, antioxidant (168) 0.25%; the mass ratio of the cortical component to the bridging component is 1:1.5; S2. The bridging fiber and the polypropylene fiber are respectively laid after opening and impurity removal to form a bridging fiber web and a polypropylene fiber web. After covering the bridging fiber web on the surface of the polypropylene fiber web, it is heated to 120 °C for reinforcement and molding to obtain a non - woven fabric substrate, and the non - woven fabric substrate is subjected to corona treatment; S3. The phase - change microcapsules, aqueous polyurethane resin, deionized water, magnetic dicyandiamide microcapsules, 2 - ethyl - 4 - methylimidazole, and polyether - modified silicone are mixed and stirred evenly to obtain a phase - change coating, and the phase - change coating is thermally transferred and printed at 145 °C on the surface of the bridging fiber web of the non - woven fabric substrate; Among them, the phase - change coating includes the following components by mass percentage: phase - change microcapsules 40%, aqueous polyurethane resin 40%, deionized water 10%, dicyandiamide microcapsules 8%, 2 - ethyl - 4 - methylimidazole 1.5%, polyether - modified silicone 0.5%; the structure of the phase - change microcapsules is composed of polyurethane resin wrapping the phase - change material, and the phase - change temperature of the phase - change material is 28 °C; the structure of the magnetic dicyandiamide microcapsules is composed of polyethylene wax wrapping LB - A modified dicyandiamide, and nano - iron oxide powder is filled in the polyethylene wax, and the mass ratio of polyethylene wax to nano - iron oxide powder is 5:1; S4. During the thermal transfer printing of the phase - change coating, when the phase - change coating is coated on the surface of the transfer film, the magnetic dicyandiamide microcapsules are adsorbed by the magnetic plate, so that the magnetic dicyandiamide microcapsules migrate concentratedly to the side where the phase - change coating contacts the bridging fiber web; S5. The phase - change coating is thermally dried at 90 °C on the surface of the non - woven fabric substrate and then cured to form a phase - change coating, and the phase - change coating and the non - woven fabric substrate together form a cool - feeling non - woven fabric.

[0035] Comparative Example 1 S1. After opening and impurity removal, polyethylene fibers and polypropylene fibers are respectively laid to form a polyethylene fiber mesh and a polypropylene fiber mesh. After covering the polyethylene fiber mesh on the surface of the polypropylene fiber mesh, it is heated to 120 °C for reinforcement and molding to obtain a non-woven fabric substrate, and the non-woven fabric substrate is subjected to corona treatment; Among them, the polyethylene resin in the polyethylene fiber is composed of linear low-density polyethylene and low-density polyethylene, and the mass ratio of linear low-density polyethylene to low-density polyethylene is 1:1; S2. Phase change microcapsules, waterborne polyurethane resin, deionized water, and polyether-modified silicone are mixed and stirred evenly to obtain a phase change coating, and the phase change coating is thermally transferred and printed at 145 °C to cover the surface of the polyethylene fiber mesh of the non-woven fabric substrate; Among them, the phase change coating includes the following components by mass percentage: 42% of phase change microcapsules, 45.5% of waterborne polyurethane resin, 12% of deionized water, and 0.5% of polyether-modified silicone; the structure of the phase change microcapsules is composed of a polyurethane resin wrapping a phase change material, and the phase change temperature of the phase change material is 28 °C; S4. After the phase change coating is thermally dried at 90 °C on the surface of the non-woven fabric substrate, it is cured to form a phase change coating, and the phase change coating and the non-woven fabric substrate together form a cool-sensation non-woven fabric.

[0036] Comparative Example 2 Referring to the Chinese patent with the publication (announcement) number of CN112726199B, a cool-sensation non-woven fabric obtained according to Example 2 in the specification of this patent document.

[0037] The following tests are carried out on the cool-sensation non-woven fabrics obtained in all the above examples and comparative examples: 1. Washing test: The cool-sensation non-woven fabric is washed 5 times, and then the peeling area of the coating on the surface of the cool-sensation non-woven fabric is measured; 2. Tape peeling test: A standard is pressed on the coating surface of the cool-sensation non-woven fabric and then quickly torn off, and then the peeling area of the coating on the surface of the cool-sensation non-woven fabric is measured; 3. Cross-cut test: 10×10 grid-shaped incisions with a spacing of 1-2 mm are made on the coating surface of the cool-sensation non-woven fabric, then a label is pressed on the surface of the grid-shaped incisions and quickly torn off, and finally the peeling area of the coating on the surface of the cool-sensation non-woven fabric is measured.

[0038] The results of the coating peeling rate obtained from the above washing test, tape peeling test, and cross-cut test are shown in Table 1 below.

[0039]

[0040] Table 1 As can be seen from the data in Table 1, the coatings of the cool-sensation non-woven fabrics in Examples 1, 2, 3, and 4 based on the technical solution of the present invention all have strong adhesion. In Comparative Example 1, based on Example 1, the cooperation of the bridging component and the curing agent was cancelled, and the coating adhered to the surface of the non-woven fabric relying on the viscous components in the coating. The technical solution of Comparative Example 1 is similar to the common non-woven fabrics with coatings on the market at present, such as the technical solution of Comparative Example 2. The coating adhesion of the cool-sensation non-woven fabrics in Comparative Example 1 and Comparative Example 2 is poor, and there is still a large room for improvement. In Example 4, on the basis of Example 1, nano-ferric oxide with magnetism was added to the shell of the dicyandiamide microcapsules. During the thermal transfer printing process of the phase change coating, the magnetic dicyandiamide microcapsules were concentrated and migrated close to the side of the bridging fiber mesh through the mutual attraction between the magnetic plate and the nano-ferric oxide. The dicyandiamide released after the melting of the shell of the magnetic dicyandiamide microcapsules can better contact the epoxy resin of the bridging fibers, improving the crosslinking and curing strength between the coating and the bridging fiber mesh, so that the coating of the cool-sensation non-woven fabric in Example 4 has stronger adhesion.

[0041] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating, characterized in that: The following steps are involved: S1, spinning the cortex component and the bridging component through a bicomponent melt spinning machine to obtain a bridging fiber with a sheath-core structure, wherein the structure of the bridging fiber is composed of the cortex component wrapping the bridging component; S2, after loosening and removing impurities from the bridging fibers and the main fibers, laying them separately to form a bridging fiber web and a main fiber web, covering the bridging fiber web on the surface of the main fiber web and then heating and reinforcing the bridging fiber web to obtain a non-woven fabric substrate; Among them, the melting temperature of each component in the non-woven fabric substrate is: main fiber > bridging component > cortical component; S3, mixing and stirring the phase change microcapsules, film-forming agent, solvent, curing agent and coating additive to obtain a phase change coating, and covering the surface of the bridge fiber web of the non-woven fabric substrate with the phase change coating by thermal transfer printing; During the thermal transfer printing process, the skin layer component and the core layer component are heated to a molten state, and the core layer component undergoes a cross-linking and curing reaction with the curing agent in the phase change coating; S4. The phase change coating is dried on the surface of the non-woven fabric substrate to form a phase change coating. The phase change coating and the non-woven fabric substrate together form a cool non-woven fabric.

2. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The bridging component includes the following components by mass percentage: 86% to 92% of bisphenol F epoxy resin, 5% to 10% of nano silicon dioxide, 1% to 3% of dispersant, and 0.5% to 1% of a first antioxidant.

3. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The coating additives include accelerators and wetting agents, and the phase change coating includes the following components by mass percentage: 30% to 50% phase change microcapsules, 30% to 50% film formers, 5% to 15% solvents, 5% to 10% curing agents, 1% to 2% accelerators, and 0.2% to 0.5% wetting agents.

4. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The curing agent is in granular form and consists of dicyandiamide wrapped in the interior by a thermoplastic polymer on the surface. The mass ratio of the thermoplastic polymer to the dicyandiamide in the curing agent is 1:(1-3).

5. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The phase change microcapsule is composed of a polyurethane resin on the surface and a phase change material inside, the phase change temperature of the phase change material is 20-30° C., and the mass ratio of the polyurethane resin to the phase change material in the phase change microcapsule is 1:(1-2).

6. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The skin layer composition includes the following components by mass percentage: polyethylene resin 90% to 94%, maleic anhydride grafted low-density polyethylene 5% to 8%, lubricant 0.5% to 2%, and second antioxidant 0.2% to 1%; The polyethylene resin includes linear low-density polyethylene and low-density polyethylene, and the mass ratio of the linear low-density polyethylene to the low-density polyethylene is 1:

1.

7. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The main fiber is selected from polypropylene fiber and polyester fiber.

8. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The mass ratio of the cortical component to the bridging component in the bridging fiber is 1:(1-2).

9. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The gram weight of the non-woven fabric substrate is 20-100 gsm, and the mass ratio of the bridging fiber web to the main fiber web in the non-woven fabric substrate is 1:(3-5).

10. The method for producing a cool nonwoven fabric with a phase-change heat-absorbing coating according to claim 1, characterized in that: The heating temperature during the reinforcement and molding process of the non-woven fabric substrate is 115-120° C.; the heating temperature during the thermal transfer printing process of the phase change coating is 130-150° C.

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