High-tear-strength printed crape and production method thereof

Abstract

The invention relates to a high-tear-strength printed crape and a production method thereof, and relates to the technical field of textiles. The after-finishing agent comprises the following components in parts by mass: 10-18 parts of core-shell structure elastic particles, 7-9 parts of a bio-based cross-linking agent, 3-5 parts of modified nano cellulose fibers, 1-2 parts of a catalyst, 1.5-2.5 parts of a stabilizer and the balance of water, totaling 100 parts. The production method comprises the following steps: processing fibers into yarns, and weaving to obtain crape; pretreating the crape, including singeing, desizing, boiling off, bleaching and finishing, and finishing by adopting an after-finishing agent to obtain the pretreated crape; printing the pretreated crape to obtain a printed crape; the printed crape is shaped, the printing effect is fixed, and the high-tear-strength printed crape is obtained. The crape has the effect of improving the tear resistance of the printed crape, and the crape has good softness and air permeability.

Description

Technical Field

[0001] The present application relates to the field of textile technology, and in particular to a high-tear strength printed crepe and a production method thereof. Background Art

[0002] As one of the traditional pillar industries, the textile industry's product performance is closely linked to people's daily lives. With socioeconomic development and rising living standards, consumer demands for textiles have evolved from simple functionality to multiple dimensions, encompassing comfort, durability, and aesthetics. In the apparel sector, printed crepe, with its unique pleated texture and rich pattern designs, has become a popular product in the market, widely used in a variety of clothing. However, despite its exceptional pattern diversity and vibrant colors, printed crepe's mechanical properties, particularly tear strength, have become a bottleneck restricting its further development.

[0003] To address this issue, common practices in the current textile industry include increasing fabric thickness or using special fiber materials. Increasing fabric thickness is a simple and direct method that increases the fiber content per unit area to enhance the overall strength of the fabric. However, this method causes the fabric to become thicker and its breathability to decrease, affecting the comfort of wearing. Another method is to use high-strength fibers, such as polyester or nylon, to replace traditional fiber materials. In addition, there are means to improve fabric performance by optimizing weaving processes or surface treatment technologies. However, although these methods can improve tear strength to a certain extent, it is often difficult to take into account the feel and softness of the fabric. While improving the tear strength, the breathability and softness of the fabric are sacrificed, resulting in a significant reduction in the comfort of the final product, so there is room for improvement. Summary of the Invention

[0004] In order to improve the performance of printed crepe, the present application provides a high tear strength printed crepe and a production method thereof.

[0005] The present application provides a high tear strength printed crepe and a production method thereof using the following technical solutions: In the first aspect, the present application provides a high tear strength printed crepe, which adopts the following technical solution: A high tear strength printed crepe is finished with a finishing agent, wherein the finishing agent comprises the following components in parts by weight: 10-18 parts of core-shell structure elastic particles 7-9 parts bio-based cross-linker 3-5 parts modified nanocellulose fiber 1-2 parts catalyst 1.5-2.5 parts stabilizer Add water to make up to 100 parts.

[0006] The core-shell elastic particles, with their double-layer structure consisting of a flexible polymer core and cross-linking groups in the shell, form a deformable elastic network between fibers, enhancing tear resistance by absorbing tearing energy. Meanwhile, the flexible core reduces the hardening of the hand caused by rigid cross-linking. The bio-based cross-linker contains multiple hydroxyl and amino groups, which interweave with the fibers and nanomaterials through hydrogen and covalent bonds to form a flexible bridging structure. This not only enhances interfacial bonding to increase strength, but also preserves the fabric's bulk due to the flexible characteristics of the bio-based molecular chains. Modified nanocellulose fibers are uniformly dispersed in the system at the nanoscale, forming a three-dimensional reinforced network by physically filling the fiber pores and chemically anchoring them. Their high aspect ratio effectively transfers stress and reduces the propagation of cracks caused by tearing, while the nano-scale gaps maintain the fabric's breathability. The catalyst accelerates the cross-linking reaction, ensuring the formation of dense but non-rigid chemical bonds between the elastic particles and the fibers. The stabilizer prevents nanomaterial agglomeration by regulating the system's pH and dispersibility, ensuring uniform distribution of all components. Ultimately, the fabric achieves improved tear resistance while retaining the fiber's natural pore structure and flexible deformation ability, thus achieving a balance between softness and breathability.

[0007] Preferably, the raw materials for preparing the core-shell structured elastic particles include hydrophobically modified nano-silica, graphene oxide modified polyurethane prepolymer and bisphenol A epoxy resin.

[0008] Hydrophobically modified nano-silica acts as a rigid core layer. With its nanoscale size effect and high hardness, it is evenly dispersed in the fiber gaps to form a stress dispersion center, effectively hindering the expansion of cracks caused by tearing. At the same time, hydrophobic modification reduces particle agglomeration, ensuring that the pore structure of the fabric is unobstructed to maintain breathability; graphene oxide modified polyurethane prepolymer constitutes a flexible shell layer, in which the elastic chain segments of polyurethane give the particles the ability to deform and absorb energy through stretching and slipping. The layered structure of graphene oxide forms a physical anchor with the fiber surface group through π-π stacking, enhancing the interface bonding between the particles and the fiber, and reducing the phenomenon of peeling between the rigid core layer and the flexible shell layer. It is found that bisphenol A epoxy resin acts as a cross-linking bridging agent to form a moderate chemical cross-linking network inside the shell layer, which not only improves the cohesive strength of the shell layer to stabilize the core-shell structure, but also avoids excessive hardening of the material through controllable cross-linking density, so that the particles can undergo reversible deformation rather than brittle fracture when subjected to stress; the three are combined to form a core-shell structure that is both rigid and flexible. The core layer supports stress, the shell layer buffers deformation, and the cross-linking network stabilizes the structure. Ultimately, while improving the tear resistance of the fabric, the elastic deformation ability of the flexible shell layer retains the relative slip space between fibers to maintain softness, and the uniform dispersion of nanoparticles avoids clogging of fiber pores to ensure air permeability, thereby achieving multifunctional synergistic enhancement.

[0009] Preferably, the mass ratio of the hydrophobically modified nano-silica, graphene oxide modified polyurethane prepolymer and bisphenol A epoxy resin is 1:2.3:(0.05-0.08).

[0010] The hydrophobically modified nano-silica prepared according to the above mass ratio has high tearing strength and good softness and air permeability.

[0011] Preferably, the core-shell structured elastic particles are prepared by the following steps: The hydrophobically modified nano-silica is dispersed in a dispersion containing a graphene oxide-modified polyurethane prepolymer, ultrasonicated, and bisphenol A epoxy resin and dibutyltin dilaurate are added. The mixture is heated and stirred for reaction to obtain a core-shell emulsion. The core-shell emulsion is spray-dried to obtain core-shell elastic particles.

[0012] The core-shell structured elastic particles prepared according to the above steps can effectively improve the tear resistance, softness and air permeability of printed crepe.

[0013] Preferably, the raw materials for preparing the bio-based cross-linking agent include chitosan, 3-chloro-2-hydroxypropyltrimethylammonium chloride and citric acid.

[0014] The amino and hydroxyl groups on the chitosan molecular chain can form hydrogen bonds and covalent bonds with fiber surface groups and other components, respectively, to construct a flexible cross-linked network. At the same time, the natural polysaccharide structure imparts skin-friendliness and biocompatibility to the fabric. 3-Chloro-2-hydroxypropyltrimethylammonium chloride introduces cationic groups through a quaternization reaction. On the one hand, this neutralizes the negative charge on the fiber surface to reduce electrostatic adsorption and improve the smoothness and softness of the fabric. On the other hand, it increases the distance between the chitosan molecular chains to reduce intermolecular hydrogen bonding and avoid hardening and brittleness of the material after cross-linking. Citric acid, as a polycarboxylic acid cross-linker, undergoes an amidation reaction with the chitosan amino group through the carboxyl group, forming chemical bridges between the molecular chains. Its three-dimensional carboxylic acid structure can induce chitosan to form a loose and porous cross-linked network, thereby strengthening the inter-fiber bonding to improve tear resistance while retaining the internal pore channels of the fabric to maintain breathability. The combination of these three factors gives the bio-based cross-linker the characteristics of cationic lubrication, flexible bridging, and a porous network. It not only enhances mechanical strength through chemical cross-linking, but also improves the soft feel and breathability of the fabric through charge regulation and structural design.

[0015] Preferably, the mass ratio of chitosan, 3-chloro-2-hydroxypropyltrimethylammonium chloride and citric acid is 1:0.4:(0.2-0.4).

[0016] The bio-based cross-linking agent prepared according to the above mass ratio can effectively improve the tear resistance, softness and air permeability of printed crepe.

[0017] Preferably, the raw materials for preparing the modified nanocellulose fibers include nanocellulose fibers, a silane coupling agent and polyethyleneimine.

[0018] Nanocellulose fibers, with their high aspect ratio and rigid skeleton characteristics, are evenly distributed among fabric fibers as a reinforcing phase, improving tear resistance through physical entanglement and stress transfer; silane coupling agents are anchored on the surface of nanocellulose through hydroxyl condensation reactions, and their organic functional groups form covalent bonds with polyurethane, crosslinking agents, etc. in the finishing agent, enhancing interfacial bonding, making the nanofibers a stress conduction hub and effectively dispersing tear loads; polyethyleneimine reacts with the active groups of the silane coupling agent through amino groups to form a flexible coating on the surface of nanocellulose. On the one hand, it improves fiber dispersion through the charge repulsion effect to avoid agglomeration and clogging of fabric pores; on the other hand, the flexible chain segments give the nanofibers deformation ability, reducing the hardening of the feel caused by the rigid reinforcing phase; the three work synergistically to improve tear resistance while retaining the softness and breathability of the fabric through flexible interfaces and nanoscale pores, and the hydrophilicity of polyethyleneimine further enhances the wettability of the finishing agent and fibers, synergistically improving the uniformity and durability of the finishing effect.

[0019] Preferably, the modified nanocellulose fibers are prepared by the following steps: The nanocellulose fibers are dispersed in a solvent and ultrasonicated to obtain a fiber dispersion; a silane coupling agent is added to the fiber dispersion, the pH is adjusted to acidic, the mixture is heated and stirred for reaction, the mixture is centrifuged to obtain a product, the product is washed, the washed product is dispersed in a solvent, polyethyleneimine is added, the mixture is heated and stirred for reaction, the product is centrifuged, washed, and freeze-dried to obtain modified nanocellulose fibers.

[0020] The modified nanocellulose fibers prepared according to the above preparation steps have good dispersibility and can effectively improve the tear resistance, softness and air permeability of printed crepe.

[0021] In a second aspect, the present application provides a method for producing high tear strength printed crepe, which adopts the following technical solution: A method for producing a high tear strength printed crepe, comprising the following steps: (1) Blending fibers and processing them into yarn through processes such as opening, carding, combing, drawing, roving, and spinning; (2) weaving the yarn to obtain crepe; (3) pre-treating the crepe, including singeing, desizing, scouring, bleaching and finishing, and using a finishing agent to obtain a pre-treated crepe; (4) printing the pretreated crepe to obtain printed crepe; (5) The printed crepe is shaped to fix the printing effect and obtain a printed crepe with high tear strength.

[0022] The high tear strength printed crepe prepared according to the above steps has good tear resistance, softness and breathability, and maintains a good printing effect and a comfortable wearing experience.

[0023] Preferably, the finishing step includes padding, and after padding, it is first pre-dried with hot air, and then cured by combining infrared rays and hot air in stages to cross-link and fix the finishing agent.

[0024] Hot air pre-drying uses mild heat to remove most of the moisture on the fabric surface, preventing the finishing agent from migrating due to sudden heat, and at the same time allowing the core-shell elastic particles to initially spread on the fiber surface; the segmented heating and curing combined with infrared and hot air achieves rapid penetration and uniform curing through the dual heat source characteristics. Infrared rays quickly increase the internal temperature of the fabric through radiation heat transfer, activating the initial reaction between the crosslinker in the finishing agent and the fiber, while hot air ensures uniform surface and internal temperature of the fabric through convection heat transfer, promoting the melting and diffusion of the shell polymer of the core-shell particles and the formation of a continuous elastic film; segmented heating can reduce the problem of stress concentration in the fiber caused by sudden temperature changes, and at the same time match the active temperature range of the catalyst in the finishing agent, so that a dual anchoring structure of physical entanglement and chemical crosslinking is formed between the core-shell particles, nanocellulose and the fiber, which not only ensures the uniform distribution of the finishing agent at the fiber interface, but also avoids the hardening of the fabric caused by excessive crosslinking, ultimately achieving improved tear resistance while maintaining the softness and breathability of the fabric.

[0025] In summary, this application includes at least one of the following beneficial technical effects: 1. The core-shell elastic particles, with their dual-layer structure consisting of a flexible polymer core and cross-linking groups in the shell, form a deformable elastic network between fibers. This absorbs tear energy to enhance tear resistance, while the flexible core reduces the hardening of the fabric caused by rigid cross-linking. The bio-based cross-linker contains multiple hydroxyl and amino groups, which interweave with the fibers and nanomaterials through hydrogen and covalent bonds to form a flexible bridging structure. This not only enhances interfacial bonding to increase strength, but also preserves the fabric's bulk due to the flexible nature of the bio-based molecular chains. Modified nanocellulose fibers are uniformly dispersed in the system at the nanoscale, forming a three-dimensional reinforced network by physically filling the fiber pores and chemically anchoring them. Their high aspect ratio effectively transfers stress and reduces the propagation of cracks caused by tearing, while the nano-scale gaps maintain the fabric's breathability. The catalyst accelerates the cross-linking reaction, ensuring a dense but non-rigid chemical bond between the elastic particles and the fibers. The stabilizer controls the pH and dispersion of the system to prevent nanomaterial agglomeration and ensure uniform distribution of all components. Ultimately, the fabric achieves enhanced tear resistance while retaining the fibers' natural pore structure and flexible deformation ability, achieving a balance between softness and breathability.

[0026] 2. Hydrophobically modified nano-silica acts as a rigid core layer. With its nanoscale size effect and high hardness, it is evenly dispersed in the fiber gaps to form a stress dispersion center, effectively hindering the expansion of cracks caused by tearing. At the same time, hydrophobic modification reduces particle agglomeration, ensuring that the fabric pore structure is unobstructed to maintain breathability; graphene oxide modified polyurethane prepolymer constitutes a flexible shell layer, in which the elastic chain segments of polyurethane give the particles the ability to deform and absorb energy through stretching and slipping. The layered structure of graphene oxide forms a physical anchor with the fiber surface groups through π-π stacking, enhancing the interfacial bonding between the particles and the fiber, and reducing the peeling phenomenon between the rigid core layer and the flexible shell layer. Appearance; Bisphenol A epoxy resin acts as a cross-linking bridging agent to form a moderate chemical cross-linking network inside the shell layer, which not only improves the cohesive strength of the shell layer to stabilize the core-shell structure, but also avoids excessive hardening of the material through controllable cross-linking density, so that the particles can undergo reversible deformation rather than brittle fracture when subjected to stress; the three are combined to form a core-shell structure that is both rigid and flexible. The core layer supports stress, the shell layer buffers deformation, and the cross-linking network stabilizes the structure. Ultimately, while improving the tear resistance of the fabric, the elastic deformation ability of the flexible shell layer is used to retain the relative slip space between fibers to maintain softness, and the uniform dispersion of nanoparticles avoids clogging of fiber pores to ensure air permeability, thereby achieving multifunctional synergistic enhancement.

[0027] 3. The amino and hydroxyl groups on the chitosan molecular chain can form hydrogen bonds and covalent bonds with fiber surface groups and other components, respectively, to construct a flexible cross-linked network. At the same time, the natural polysaccharide structure imparts skin-friendliness and biocompatibility to the fabric. 3-Chloro-2-hydroxypropyltrimethylammonium chloride introduces cationic groups through a quaternization reaction. On the one hand, this neutralizes the negative charge on the fiber surface to reduce electrostatic adsorption and improve the smoothness and softness of the fabric. On the other hand, it increases the distance between the chitosan molecular chains to reduce intermolecular hydrogen bonding and avoid hardening and brittleness of the material after cross-linking. Citric acid, as a polycarboxylic acid cross-linker, undergoes an amidation reaction with the chitosan amino group through the carboxyl group, forming chemical bridges between the molecular chains. Its three-dimensional carboxylic acid structure can induce chitosan to form a loose and porous cross-linked network, thereby strengthening the inter-fiber bonding to improve tear resistance while retaining the internal pore channels of the fabric to maintain breathability. The combination of these three factors gives the bio-based cross-linker the properties of cationic lubrication, flexible bridging, and a porous network. It not only enhances mechanical strength through chemical cross-linking, but also improves the soft feel and breathability of the fabric through charge regulation and structural design. DETAILED DESCRIPTION

[0028] The present application discloses a high tear strength printed crepe and a production method thereof. The raw materials used in the present application can be obtained from commercially available raw materials unless otherwise specified. The present application is further described in detail in conjunction with the following examples and comparative examples: Raw materials: Nano-silicon dioxide with a particle size of 50 nm, silane coupling agent KH-570 (CAS No.: 2530-85-0), graphene oxide model XFSG01, purchased from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., polytetramethylene glycol (CAS No.: 25190-06-1), with a molecular weight of 2000, isophorone diisocyanate (CAS No.: 4098-71-9), bisphenol A type epoxy resin is epoxy resin E-51 (CAS No.: 6 1788-97-4), dibutyltin dilaurate (CAS No.: 77-58-7), chitosan (CAS No.: 9012-76-4), deacetylation degree of 95%, 3-chloro-2-hydroxypropyltrimethylammonium chloride (CAS No.: 3327-22-8), citric acid (CAS No.: 77-92-9), sodium hypophosphite (CAS No.: 7681-53-0), nanocellulose fiber (CAS No.: 9004-34-6), aspect ratio of 100, silane coupling agent KH-550 (CAS No.: 919-30-2), polyethyleneimine (CAS No.: 9002-98-6), stabilizer is poloxamer (CAS No.: 9003-11-6).

[0029] Example 1 Preparation of core-shell structured elastic particles 20 g of nano-silica was dispersed in 200 mL of anhydrous ethanol. After ultrasonic treatment for 30 min, 1 g of silane coupling agent KH-570 was added, and a 1 mol / L glacial acetic acid aqueous solution was added to adjust the pH to 4. The mixture was stirred at 200 rpm at 60 ° C for 4 h, washed with anhydrous ethanol after centrifugation, and vacuum dried at 80 ° C to obtain hydrophobically modified nano-silica.

[0030] The graphene oxide was vacuum dried at 100°C for 24 hours to remove moisture to obtain anhydrous graphene oxide; 0.73g of anhydrous graphene oxide was dispersed in 80mL of N,N-dimethylformamide and ultrasonicated for 1 hour to obtain a graphene oxide dispersion; 36.5g of polytetrahydrofuran diol and 12.77g of isophorone diisocyanate were mixed, stirred at 80°C at 200rpm for 2 hours, the graphene oxide dispersion was added within 1 hour, and the stirring reaction was continued at 80°C at 200rpm for 3 hours to obtain a dispersion of graphene oxide modified polyurethane prepolymer.

[0031] 14.93 g of hydrophobically modified nano-silica was dispersed into a dispersion containing 34.33 g of graphene oxide-modified polyurethane prepolymer, ultrasonically dispersed for 30 min, 0.74 g of epoxy resin E-51 and 0.01 g of dibutyltin dilaurate were added, and the mixture was stirred at 80 ° C and 200 rpm for 2 h to obtain a core-shell emulsion. The core-shell emulsion was spray dried at 120 ° C, with an inlet air temperature of 180 ° C and an outlet air temperature of 90 ° C to obtain core-shell structured elastic particles.

[0032] Preparation of bio-based cross-linkers 12.5 g of chitosan was dissolved in 500 mL of a 3% glacial acetic acid aqueous solution to obtain a chitosan solution. 5 g of 3-chloro-2-hydroxypropyltrimethylammonium chloride was added to the chitosan solution, and the mixture was stirred at 200 rpm at 60° C. for 2 h. 2.5 g of citric acid and 0.3 g of sodium hypophosphite were added, the pH was adjusted to 6.5, the temperature was raised to 80° C., the mixture was stirred at 200 rpm for 1.5 h, and the mixture was freeze-dried at −20° C. to obtain a bio-based crosslinker.

[0033] Preparation of modified nanocellulose fibers 10 g of nanocellulose fiber was dispersed in 1.5 L of deionized water and ultrasonicated to obtain a fiber dispersion; 1 g of silane coupling agent KH-550 was added to the fiber dispersion, the pH was adjusted to 4 with glacial acetic acid, the reaction was stirred at 300 rpm at 60 ° C for 3 hours, and the product was obtained by centrifugation. The washed product was dispersed in 1.5 L of deionized water, 0.5 g of polyethyleneimine was added, the reaction was stirred at 250 rpm at 50 ° C for 2 hours, centrifuged, washed with deionized water, and freeze-dried at -20 ° C to obtain modified nanocellulose fiber.

[0034] Preparation of finishing agent 10 g of core-shell structured elastic particles and 3 g of modified nanocellulose fibers were mixed and dispersed in 50 mL of deionized water and ultrasonicated for 30 minutes. Then, 7 g of a bio-based crosslinker was added and stirred at 250 rpm at 50°C for 30 minutes. Then, 1 g of dibutyltin dilaurate and 1.5 g of a stabilizer were added and stirred at 200 rpm for 60 minutes. The remaining amount of water was supplemented to a total mass of 100 g. After stirring for 15 minutes, a finishing agent was obtained.

[0035] Preparation of printed crepe with high tear strength (1) 30% polyester, 40% nylon and 30% spandex fibers are blended and processed into yarn through opening, carding, combing, drawing, roving and spinning; (2) weaving the yarn using a rapier loom to obtain a crepe; (3) Pre-treating the crepe, including singeing, desizing, scouring, bleaching and finishing, using a post-finishing agent for finishing, and padding the crepe with a uniform padder. The pneumatic pressure line pressure is 200 N / cm, the rolling rate is 75%, and the padding temperature is 40°C. After padding, it is first pre-dried with 80°C hot air for 10 minutes to a moisture content of 30%, and then cured in a staged infrared and hot air combined drying machine. It is first baked at 100°C for 5 minutes, then heated to 130°C at a rate of 5°C / min and baked for 8 minutes to fully cross-link and fix the finishing agent, thereby obtaining a pre-treated crepe. (4) performing digital inkjet printing on the pretreated crepe using environmentally friendly reactive dyes to obtain printed crepe; (5) The printed crepe is shaped at a temperature of 160°C to fix the printing effect and obtain a printed crepe with high tear strength.

[0036] Example 2 Preparation of core-shell structured elastic particles 20 g of nano-silica was dispersed in 200 mL of anhydrous ethanol. After ultrasonic treatment for 30 min, 1 g of silane coupling agent KH-570 was added, and a 1 mol / L glacial acetic acid aqueous solution was added to adjust the pH to 4. The mixture was stirred at 200 rpm at 60 ° C for 4 h, washed with anhydrous ethanol after centrifugation, and vacuum dried at 80 ° C to obtain hydrophobically modified nano-silica.

[0037] The graphene oxide was vacuum dried at 100°C for 24 hours to remove moisture to obtain anhydrous graphene oxide; 0.73g of anhydrous graphene oxide was dispersed in 80mL of N,N-dimethylformamide and ultrasonicated for 1 hour to obtain a graphene oxide dispersion; 36.5g of polytetrahydrofuran diol and 12.77g of isophorone diisocyanate were mixed, stirred at 80°C at 200rpm for 2 hours, the graphene oxide dispersion was added within 1 hour, and the stirring reaction was continued at 80°C at 200rpm for 3 hours to obtain a dispersion of graphene oxide modified polyurethane prepolymer.

[0038] 14.79 g of hydrophobically modified nano-silica was dispersed into a dispersion containing 34.02 g of graphene oxide-modified polyurethane prepolymer, ultrasonically dispersed for 30 min, 1.19 g of epoxy resin E-51 and 0.01 g of dibutyltin dilaurate were added, and the mixture was stirred at 80 ° C and 200 rpm for 2 h to obtain a core-shell emulsion. The core-shell emulsion was spray dried at 120 ° C, with an inlet air temperature of 180 ° C and an outlet air temperature of 90 ° C to obtain core-shell structured elastic particles.

[0039] Preparation of bio-based cross-linkers 11.12 g of chitosan was dissolved in 500 mL of a 3% mass concentration of glacial acetic acid aqueous solution to obtain a chitosan solution. 4.44 g of 3-chloro-2-hydroxypropyltrimethylammonium chloride was added to the chitosan solution, and the mixture was stirred at 60° C. and 200 rpm for 2 h. 4.44 g of citric acid and 0.3 g of sodium hypophosphite were added, the pH was adjusted to 6.5, the temperature was raised to 80° C., the mixture was stirred at 200 rpm for 1.5 h, and the mixture was freeze-dried at −20° C. to obtain a bio-based crosslinker.

[0040] Preparation of modified nanocellulose fibers 10 g of nanocellulose fiber was dispersed in 1.5 L of deionized water and ultrasonicated to obtain a fiber dispersion; 1 g of silane coupling agent KH-550 was added to the fiber dispersion, the pH was adjusted to 4 with glacial acetic acid, the reaction was stirred at 300 rpm at 60 ° C for 3 hours, and the product was obtained by centrifugation. The washed product was dispersed in 1.5 L of deionized water, 0.5 g of polyethyleneimine was added, the reaction was stirred at 250 rpm at 50 ° C for 2 hours, centrifuged, washed with deionized water, and freeze-dried at -20 ° C to obtain modified nanocellulose fiber.

[0041] Preparation of finishing agent 18 g of core-shell structured elastic particles and 5 g of modified nanocellulose fibers were mixed and dispersed in 50 mL of deionized water and ultrasonicated for 30 minutes. Then, 9 g of a bio-based crosslinker was added and stirred at 250 rpm at 50° C. for 30 minutes. 2 g of dibutyltin dilaurate and 2.5 g of a stabilizer were added and stirred at 200 rpm for 60 minutes. The remaining amount of water was supplemented to a total mass of 100 g. After stirring for 15 minutes, a finishing agent was obtained.

[0042] Preparation of printed crepe with high tear strength (1) 30% polyester, 40% nylon and 30% spandex fibers are blended and processed into yarn through opening, carding, combing, drawing, roving and spinning; (2) weaving the yarn using a rapier loom to obtain a crepe; (3) Pre-treating the crepe, including singeing, desizing, scouring, bleaching and finishing, using a post-finishing agent for finishing, and padding the crepe with a uniform padder. The pneumatic pressure line pressure is 200 N / cm, the rolling rate is 75%, and the padding temperature is 40°C. After padding, it is first pre-dried with 80°C hot air for 10 minutes to a moisture content of 30%, and then cured in a staged infrared and hot air combined drying machine. It is first baked at 100°C for 5 minutes, then heated to 130°C at a rate of 5°C / min and baked for 8 minutes to fully cross-link and fix the finishing agent, thereby obtaining a pre-treated crepe. (4) performing digital inkjet printing on the pretreated crepe using environmentally friendly reactive dyes to obtain printed crepe; (5) The printed crepe is shaped at a temperature of 180°C to fix the printing effect and obtain a printed crepe with high tear strength.

[0043] Example 3 Preparation of core-shell structured elastic particles 20 g of nano-silica was dispersed in 200 mL of anhydrous ethanol. After ultrasonic treatment for 30 min, 1 g of silane coupling agent KH-570 was added, and a 1 mol / L glacial acetic acid aqueous solution was added to adjust the pH to 4. The mixture was stirred at 200 rpm at 60 ° C for 4 h, washed with anhydrous ethanol after centrifugation, and vacuum dried at 80 ° C to obtain hydrophobically modified nano-silica.

[0044] The graphene oxide was vacuum dried at 100°C for 24 hours to remove moisture to obtain anhydrous graphene oxide; 0.73g of anhydrous graphene oxide was dispersed in 80mL of N,N-dimethylformamide and ultrasonicated for 1 hour to obtain a graphene oxide dispersion; 36.5g of polytetrahydrofuran diol and 12.77g of isophorone diisocyanate were mixed, stirred at 80°C at 200rpm for 2 hours, the graphene oxide dispersion was added within 1 hour, and the stirring reaction was continued at 80°C at 200rpm for 3 hours to obtain a dispersion of graphene oxide modified polyurethane prepolymer.

[0045] 14.86 g of hydrophobically modified nano-silica was dispersed into a dispersion containing 34.18 g of graphene oxide-modified polyurethane prepolymer, ultrasonically dispersed for 30 min, 0.96 g of epoxy resin E-51 and 0.01 g of dibutyltin dilaurate were added, and the mixture was stirred at 80 ° C and 200 rpm for 2 h to obtain a core-shell emulsion. The core-shell emulsion was spray dried at 120 ° C, with an inlet air temperature of 180 ° C and an outlet air temperature of 90 ° C to obtain core-shell structured elastic particles.

[0046] Preparation of bio-based cross-linkers 11.76 g of chitosan was dissolved in 500 mL of a 3% mass concentration of glacial acetic acid aqueous solution to obtain a chitosan solution. 4.71 g of 3-chloro-2-hydroxypropyltrimethylammonium chloride was added to the chitosan solution, and the mixture was stirred at 60° C. and 200 rpm for 2 h. 3.53 g of citric acid and 0.3 g of sodium hypophosphite were added, and the pH was adjusted to 6.5. The mixture was heated to 80° C. and stirred at 200 rpm for 1.5 h. The mixture was freeze-dried at −20° C. to obtain a bio-based crosslinker.

[0047] Preparation of modified nanocellulose fibers 10 g of nanocellulose fiber was dispersed in 1.5 L of deionized water and ultrasonicated to obtain a fiber dispersion; 1 g of silane coupling agent KH-550 was added to the fiber dispersion, the pH was adjusted to 4 with glacial acetic acid, the reaction was stirred at 300 rpm at 60 ° C for 3 hours, and the product was obtained by centrifugation. The washed product was dispersed in 1.5 L of deionized water, 0.5 g of polyethyleneimine was added, the reaction was stirred at 250 rpm at 50 ° C for 2 hours, centrifuged, washed with deionized water, and freeze-dried at -20 ° C to obtain modified nanocellulose fiber.

[0048] Preparation of finishing agent 14 g of core-shell structured elastic particles and 4 g of modified nanocellulose fibers were mixed and dispersed in 50 mL of deionized water and ultrasonicated for 30 minutes. Then, 8 g of a bio-based crosslinker was added and stirred at 250 rpm at 50°C for 30 minutes. 1.5 g of dibutyltin dilaurate and 2 g of a stabilizer were added and stirred at 200 rpm for 60 minutes. The remaining amount of water was supplemented to a total mass of 100 g. After stirring for 15 minutes, a finishing agent was obtained.

[0049] Preparation of printed crepe with high tear strength (1) 30% polyester, 40% nylon and 30% spandex fibers are blended and processed into yarn through opening, carding, combing, drawing, roving and spinning; (2) weaving the yarn using a rapier loom to obtain a crepe; (3) Pre-treating the crepe, including singeing, desizing, scouring, bleaching and finishing, using a post-finishing agent for finishing, and padding the crepe with a uniform padder. The pneumatic pressure line pressure is 200 N / cm, the rolling rate is 75%, and the padding temperature is 40°C. After padding, it is first pre-dried with 80°C hot air for 10 minutes to a moisture content of 30%, and then cured in a staged infrared and hot air combined drying machine. It is first baked at 100°C for 5 minutes, then heated to 130°C at a rate of 5°C / min and baked for 8 minutes to fully cross-link and fix the finishing agent, thereby obtaining a pre-treated crepe. (4) performing digital inkjet printing on the pretreated crepe using environmentally friendly reactive dyes to obtain printed crepe; (5) The printed crepe is shaped at a temperature of 170°C to fix the printing effect and obtain a printed crepe with high tear strength.

[0050] Example 4 Example 4 is based on Example 3. The only difference between Example 4 and Example 3 is that in Example 4, the amount of hydrophobically modified nano-silica is 15.02 g, the amount of graphene oxide modified polyurethane prepolymer is 34.53 g, and the amount of bisphenol A epoxy resin is 0.45 g.

[0051] Example 5 Example 5 is based on Example 3. The only difference between Example 5 and Example 3 is that in Example 5, the amount of hydrophobically modified nano-silica is 14.71 g, the amount of graphene oxide modified polyurethane prepolymer is 33.82 g, and the amount of bisphenol A epoxy resin is 1.47 g.

[0052] Example 6 Example 6 is based on Example 3. The only difference between Example 6 and Example 3 is that in Example 6, the hydrophobically modified nano-silica is replaced by nano-silica.

[0053] Example 7 Example 7 is based on Example 3. The only difference between Example 7 and Example 3 is that in Example 7, graphene oxide is not added when preparing the graphene oxide-modified polyurethane prepolymer.

[0054] Example 8 Example 8 is based on Example 3. The only difference between Example 8 and Example 3 is that in Example 8, the amount of chitosan used is 13.34 g, the amount of 3-chloro-2-hydroxypropyltrimethylammonium chloride used is 5.33 g, and the amount of citric acid used is 1.33 g.

[0055] Example 9 Example 9 is based on Example 3. The only difference between Example 9 and Example 3 is that in Example 9, the amount of chitosan used is 10.53 g, the amount of 3-chloro-2-hydroxypropyltrimethylammonium chloride used is 4.21 g, and the amount of citric acid used is 5.26 g.

[0056] Example 10 Example 10 is based on Example 3. The only difference between Example 10 and Example 3 is that 3-chloro-2-hydroxypropyltrimethylammonium chloride is not added when preparing the bio-based cross-linking agent in Example 10.

[0057] Example 11 Example 11 is based on Example 3. The only difference between Example 11 and Example 3 is that polyethyleneimine is not added when preparing the modified nanocellulose fibers in Example 11.

[0058] Example 12 Example 12 is based on Example 3. The only difference between Example 12 and Example 3 is that in Example 12, the finishing step is followed by hot air baking at 120° C. for 10 minutes after padding.

[0059] Comparative Example 1 Comparative Example 1 is based on Example 3. The only difference between Comparative Example 1 and Example 3 is that no core-shell structured elastic particles are added in Comparative Example 1.

[0060] Comparative Example 2 Comparative Example 2 is based on Example 3. The only difference between Comparative Example 2 and Example 3 is that in Comparative Example 2, the bio-based cross-linking agent is replaced by chitosan.

[0061] Performance testing (1) Using GB / T3917.3-2009 Tear properties of textile fabrics Part 3: Determination of tear strength of trapezoidal specimens as the standard, cut a trapezoidal specimen of the specified size from the specimen and place the specimen in the equipment clamp, keeping the two cut lines straight and parallel. The gauge length is adjusted to 25 mm. Apply a continuously increasing force to the specimen at a tensile speed of 100 mm / min, so that the tear propagates along the width of the specimen. Record the tear strength until the tear reaches the specified length. The automatic electronic device will calculate the average of the highest and lowest peaks in the specified area. This average is the tear strength of the fabric. Prepare three samples for each specimen, take the average value after measurement, and record the results in Table 1.

[0062] (2) Softness test: Three samples were cut from the test piece and conditioned for 24 hours under standard atmospheric conditions of 20°C and 65% humidity. Three people with normal sensory function were selected to score the softness on a 5-point scale. The average value was taken and the results were recorded in Table 1.

[0063] (3) Select "GB / T 5453-1997 Determination of Air Permeability of Textile Fabrics" as the standard, place the sample flat on the test table of the air permeability tester, seal it well, and use a high-precision pressure sensor to test the pressure difference between the two sides of the sample, measure the flow rate, and obtain the air permeability (mm / s). Each sample is tested three times, and the average value is taken after measurement. The results are recorded in Table 1.

[0064] Table 1 Test results of tear resistance, softness and air permeability of printed crepe Test results Tear strength (N) Softness score (points) Air permeability (mm / s) Example 1 115 4.0 153 Example 2 116 4.3 157 Example 3 118 4.3 159 Example 4 107 4.3 144 Example 5 102 3.7 132 Example 6 93 3.3 126 Example 7 89 4.0 164 Example 8 98 4.3 152 Example 9 94 3.3 127 Example 10 86 3.0 163 Example 11 92 3.0 136 Example 12 106 3.7 144 Comparative Example 1 69 2.3 173 Comparative Example 2 81 2.7 155 As shown in Table 1, the tear strength of Examples 1-3 is greater than 115N, the softness score is greater than 4 points, and the air permeability is greater than 153 mm / s, which shows that the printed crepe prepared in this application has good tear resistance, softness and air permeability.

[0065] As shown in Table 1, the only difference between Examples 4-7 and Example 3 is that the mass ratio of hydrophobically modified nano-silica, graphene oxide modified polyurethane prepolymer and bisphenol A type epoxy resin in Example 4 is 1:2.3:0.03, the mass ratio of hydrophobically modified nano-silica, graphene oxide modified polyurethane prepolymer and bisphenol A type epoxy resin in Example 5 is 1:2.3:0.1, the hydrophobically modified nano-silica is replaced by nano-silica in Example 6, and graphene oxide is not added when preparing the graphene oxide modified polyurethane prepolymer in Example 7. 3, the performance has declined; this is because the ratio of the various components in the core-shell structure elastic particles has been changed. The reduction of epoxy resin will affect the crosslinking density of the shell layer, and too much will cause excessive crosslinking and increased brittleness, both of which will affect the stability of the material, thereby reducing the performance; if the nano-silica has not been hydrophobically modified, it is easy to agglomerate and disperse unevenly, resulting in an increase in stress concentration points and a significant decrease in tear strength. In addition, poor dispersion will block the fiber gaps and cause poor air permeability; if graphene is not added to the polyurethane prepolymer, it is easy to cause a decrease in the bonding force between the finishing agent and the fiber, and poor tear resistance.

[0066] As can be seen from Table 1, the only difference between Examples 8, 9, and 10 and Example 3 is that the mass ratio of chitosan, 3-chloro-2-hydroxypropyltrimethylammonium chloride, and citric acid in Example 8 is 1:0.4:0.1, the mass ratio of chitosan, 3-chloro-2-hydroxypropyltrimethylammonium chloride, and citric acid in Example 9 is 1:0.4:0.5, and 3-chloro-2-hydroxypropyltrimethylammonium chloride is not added when preparing the bio-based cross-linking agent in Example 10. Compared with Example 3, the performance of Examples 8, 9, and 10 is reduced. This is because the component ratio in the bio-based cross-linking agent is changed. Too little citric acid will lead to a decrease in the strength of the chitosan cross-linking network and weaken the inter-fiber bonding force. Too much citric acid will cause the cross-linking network to be too dense, the material hardness will increase, and the softness will decrease. Failure to use quaternary ammonium salt to modify chitosan will increase the influence of electrostatic repulsion, reduce the adsorption amount of the finishing agent, and reduce the finishing effect.

[0067] As can be seen from Table 1, the only difference between Example 11 and Example 3 is that polyethyleneimine is not added when preparing the modified nanocellulose fibers in Example 11, and the performance of Example 11 is reduced compared with Example 3; this is because polyethyleneimine is not added when preparing the modified nanocellulose fibers, resulting in poor dispersibility of the nanocellulose fibers, and the rigid structure of the nanocellulose fibers lacks a flexible coating layer, resulting in a poor feel and reduced performance.

[0068] As can be seen from Table 1, the only difference between Example 12 and Example 3 is that in Example 12, the finishing step is followed by hot air baking at 120°C for 10 minutes after padding. Compared with Example 3, the performance of Example 12 is reduced. This is because a single high-temperature rapid baking can cause the finishing agent to migrate, resulting in uneven crosslinking and a reduced finishing effect on the fiber.

[0069] As can be seen from Table 1, the only difference between Comparative Example 1 and Example 3 is that the core-shell elastic particles are not added in Comparative Example 1. As a result, the performance of Comparative Example 1 is reduced compared with Example 3. This is because without the addition of the core-shell elastic particles, the network for stress transfer between fibers is lacking, the film-forming property of the finishing agent is affected, and the softness is significantly reduced.

[0070] As can be seen from Table 1, the only difference between Comparative Example 2 and Example 3 is that the bio-based crosslinker in Comparative Example 2 is replaced with chitosan. Compared with Example 3, the performance of Comparative Example 2 is significantly reduced. This is because the chitosan lacks modification treatment when the bio-based crosslinker is replaced with chitosan, and thus cannot form a three-dimensional network, resulting in reduced mechanical properties. In addition, the lack of quaternization treatment reduces the uniformity of the finishing agent.

[0071] This specific embodiment is merely an explanation of the present application and does not limit the present application. Based on the above description, relevant personnel can make various changes and modifications without departing from the technical scope of the present application. The technical scope of the present application is not limited to the contents of the specification and must be determined according to the scope of the claims.

Claims

1. A high tear strength printed crepe, characterized by: Finishing is performed using a finishing agent, which includes the following components in parts by mass: 10-18 parts of core-shell elastic particles 7-9 parts bio-based cross-linker 3-5 parts modified nanocellulose fiber 1-2 parts catalyst 1.5-2.5 parts stabilizer Add water to make up to 100 parts.

2. The high tear strength printed crepe according to claim 1, characterized in that: The raw materials for preparing the core-shell structure elastic particles include hydrophobically modified nano-silica, graphene oxide modified polyurethane prepolymer and bisphenol A epoxy resin.

3. The high tear strength printed crepe according to claim 2, characterized in that: The mass ratio of the hydrophobically modified nano-silica, the graphene oxide modified polyurethane prepolymer and the bisphenol A epoxy resin is 1:2.3:(0.05-0.08).

4. The high tear strength printed crepe according to claim 3, characterized in that: The core-shell structured elastic particles are prepared by the following steps: The hydrophobically modified nano-silica is dispersed in a dispersion containing a graphene oxide-modified polyurethane prepolymer, ultrasonicated, and bisphenol A epoxy resin and dibutyltin dilaurate are added. The mixture is heated and stirred for reaction to obtain a core-shell emulsion. The core-shell emulsion is spray-dried to obtain core-shell elastic particles.

5. The high tear strength printed crepe according to claim 1, characterized in that: The raw materials for preparing the bio-based cross-linking agent include chitosan, 3-chloro-2-hydroxypropyltrimethylammonium chloride and citric acid.

6. The high tear strength printed crepe according to claim 5, characterized in that: The mass ratio of the chitosan, 3-chloro-2-hydroxypropyltrimethylammonium chloride and citric acid is 1:0.4:(0.2-0.4).

7. The high tear strength printed crepe according to claim 1, characterized in that: The raw materials for preparing the modified nanocellulose fibers include nanocellulose fibers, a silane coupling agent and polyethyleneimine.

8. The high tear strength printed crepe according to claim 7, characterized in that: The modified nanocellulose fibers are prepared by the following steps: The nanocellulose fibers are dispersed in a solvent and ultrasonicated to obtain a fiber dispersion; a silane coupling agent is added to the fiber dispersion, the pH is adjusted to acidic, the mixture is heated and stirred for reaction, the mixture is centrifuged to obtain a product, the product is washed, the washed product is dispersed in a solvent, polyethyleneimine is added, the mixture is heated and stirred for reaction, the product is centrifuged, washed, and freeze-dried to obtain modified nanocellulose fibers.

9. A method for producing a high tear strength printed crepe according to any one of claims 1 to 8, characterized in that: The following steps are involved: (1) Blending fibers and processing them into yarn through processes such as opening, carding, combing, drawing, roving, and spinning; (2) Weaving the yarn to obtain crepe; (3) Pre-treating the crepe, including singeing, desizing, scouring, bleaching and finishing, and using a finishing agent to obtain pre-treated crepe; (4) printing the pretreated crepe to obtain printed crepe; (5) The printed crepe is shaped to fix the printing effect and obtain a printed crepe with high tear strength.

10. The method for producing a printed crepe with high tear strength according to claim 9, characterized in that: The finishing step includes padding, followed by hot air pre-baking, and then infrared and hot air combined with segmented temperature curing to crosslink and fix the finishing agent.