A wear-resistant and anti-fouling leather surface treatment agent and preparation method thereof

Abstract

The invention discloses a kind of wear-resistant and anti-fouling leather surface treatment agent and preparation method thereof, belong to the technical field of leather treatment agent, the leather surface treatment agent comprises the following raw materials: 70-90 parts by weight of modified polyurethane emulsion for leather, 0.4-0.6 parts by weight of defoamer, 0.4-0.6 parts by weight of leveling agent, 0.8-1.2 parts by weight of wetting agent, 04-0.6 parts by weight of thickener, 1.2-1.8 parts by weight of film-forming aid, 20-40 parts by weight of water; the leather modified polyurethane emulsion adopts hydroxyl-terminated polyether modified silicone oil, hydroxyl-terminated POSS modified silicone oil, polytetrahydrofuran ether diol, dicyclohexylmethane-4,4'-diisocyanate, 2,2-dimethylol propionic acid, ethyl methacrylate and triethylamine, and is dispersed in water after reaction. The leather surface treatment agent prepared by the present invention significantly improves the wear resistance and anti-fouling performance of the leather surface treatment agent by using a specific modified polyurethane emulsion for leather, and can provide lasting protection for leather products.

Description

Technical Field

[0001] The invention belongs to the technical field of leather treatment agents, and in particular relates to a wear-resistant and anti-fouling leather surface treatment agent and a preparation method thereof. Background Art

[0002] Leather surface treatment agents are a type of leather auxiliaries used for finishing, protecting and beautifying the leather surface. They improve the appearance and performance of leather by forming a protective film on the leather surface. This type of treatment agent usually includes components such as film-forming substances, solvents and auxiliaries. It can be widely used in leather products such as furniture, shoes, handbags and car seats. By using leather surface treatment agents, the softness and glossiness of leather can be effectively increased, while improving its oil resistance, stain resistance and wear resistance. In addition, this treatment agent can also prevent oxidation, fading and aging of the leather surface, thereby extending the service life of leather products. In short, leather surface treatment agents can not only improve the appearance and feel of leather, but also enhance its durability and stability during use, making leather products more beautiful, practical and durable.

[0003] Chinese patent CN104479532A discloses a leather surface treatment agent, which is composed of the following raw materials: silicone modified polyurethane resin, water, emulsified silicone oil, silicone defoamer, polyurethane associative thickener, nano-TiO2 modified gelatin, ultrafine nano waste rubber powder, silane coupling agent. The surface treatment agent improves the firmness, softness and affinity of the coating, and has relatively stable water-repellent, oil-repellent and anti-fouling properties; Chinese patent CN103205898A discloses a skin-feel polyurethane leather surface treatment agent and its preparation method, which is composed of the following raw materials: solvent-based PU, silicone, wax , solvent, wherein the solvent-based PU is prepared from diisocyanate, polyol, chain extender, reactive silicone, antioxidant and catalyst in the presence of an organic solvent, and the silicone is one or more of methyl silicone oil, ethyl silicone oil, methylphenyl silicone oil, polyether modified silicone oil, epoxy modified silicone oil and fluorocarbon modified silicone oil. The surface treatment agent can be used on synthetic leather to improve the touch of synthetic leather, so that the synthetic leather has strong skin feel, and can also improve the scratch resistance and wear resistance of synthetic leather to a certain extent; however, the leather surface treatment agent disclosed in the above patent still needs to be improved in terms of wear resistance and anti-fouling performance. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a wear-resistant and anti-fouling leather surface treatment agent, which further improves the wear resistance and anti-fouling performance of the leather surface treatment agent by using a specific modified polyurethane emulsion for leather, and can provide long-lasting protection for leather products. The present invention also provides a preparation method of the wear-resistant and anti-fouling leather surface treatment agent.

[0005] A wear-resistant and anti-fouling leather surface treatment agent, comprising the following raw materials:

[0006] Modified polyurethane emulsion for leather, defoamer, leveling agent, wetting agent, thickener, film-forming aid and water; the modified polyurethane emulsion for leather is prepared by reacting terminal hydroxyl polyether modified silicone oil, terminal hydroxyl POSS modified silicone oil, polytetramethylene ether diol, dicyclohexylmethane-4,4'-diisocyanate, 2,2-dihydroxymethylpropionic acid, ethyl methacrylate and triethylamine, followed by dispersion with water.

[0007] Preferably, a wear-resistant and anti-fouling leather surface treatment agent is made from the following raw materials in parts by weight:

[0008] 70-90 parts by weight of modified polyurethane emulsion for leather, 0.4-0.6 parts by weight of defoamer, 0.4-0.6 parts by weight of leveling agent, 0.8-1.2 parts by weight of wetting agent, 0.4-0.6 parts by weight of thickener, 1.2-1.8 parts by weight of film-forming aid, and 20-40 parts by weight of water.

[0009] Preferably, the modified polyurethane emulsion for leather is prepared by the following method:

[0010] The polymethyl hydrogen siloxane, the terminal epoxy allyl polyether and ethylene glycol dimethyl ether are mixed, stirred and heated under a nitrogen atmosphere, and then a Custer catalyst is added and stirred continuously, and the mixture is distilled under reduced pressure to obtain a terminal epoxy polyether modified silicone oil; the terminal epoxy polyether modified silicone oil, ethylene glycol and p-toluenesulfonic acid are mixed, heated and stirred for reaction, and distilled under reduced pressure to obtain a terminal hydroxyl polyether modified silicone oil; in this step, the unsaturated bonds contained in the terminal epoxy allyl polyether are used for addition reaction with the silicon-hydrogen bonds in the polymethyl hydrogen siloxane, and then the epoxy group is used for ring opening to obtain the terminal hydroxyl polyether modified silicone oil, which can introduce the polyether structure and the organosilicon structure into the polyurethane molecule through the reaction of the hydroxyl group and the isocyanate group in the subsequent step, which helps to improve the wear resistance and stain resistance of the leather surface;

[0011] PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted, vinyl silicone oil and ethylene glycol dimethyl ether are mixed, stirred and heated under a nitrogen atmosphere, and then a Custer catalyst is added and stirred continuously, and distilled under reduced pressure to obtain a terminal hydroxyl POSS modified silicone oil; in this step, PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted is preferably used as a starting material, which contains a terminal hydroxyl structure, and the terminal hydroxyl POSS modified silicone oil is obtained by an addition reaction between the unsaturated bond of the vinyl silicone oil and the silicon-hydrogen bond of the PSS. In a subsequent step, the cage structure and the organosilicon structure are successfully introduced into the polyurethane molecule by reacting the terminal hydroxyl group with the isocyanate group, thereby solving the disadvantage of poor compatibility of the silicone oil with the polyurethane when directly using the silicone oil, and further improving the wear resistance and folding resistance of the leather surface;

[0012] The terminal hydroxyl polyether modified silicone oil, the terminal hydroxyl POSS modified silicone oil, polytetramethylene glycol, dicyclohexylmethane-4,4'-diisocyanate, 2,2-dihydroxymethyl propionic acid and dibutyltin dilaurate are mixed, heated and stirred for reaction, and then the polytetramethylene glycol is added to continue the reaction, and then cooled after the reaction is completed, N,N-dimethylformamide, ethyl methacrylate and triethylamine are added to mix evenly, heated and stirred for reaction, and then azobisisobutyronitrile is added to continue stirring, and reduced pressure distillation is performed to obtain a modified polyurethane; the modified polyurethane and water are added to a high-speed disperser for dispersion to obtain the modified polyurethane emulsion for leather; this step is based on the copolymerization of hydroxyl and isocyanate groups to obtain polyurethane, and then acrylic acid monomers are used for end-capping, and finally azobisisobutyronitrile is used to initiate methacrylate free radical polymerization to generate polyacrylic acid segments, thereby organically combining the characteristics of polyether, PSS, silicone, polyurethane and polypropylene, and significantly improving the wear resistance, folding resistance and anti-fouling properties of the leather surface treatment agent.

[0013] The modified polyurethane emulsion for leather prepared by the present invention, by adopting terminal hydroxyl polyether modified silicone oil and terminal hydroxyl POSS modified silicone oil as monomers, polyether structure, cage structure and organosilicon structure are successfully introduced into the main chain of polyurethane molecule, and polyether structure can improve the flexibility and wear resistance of polyurethane as soft segment; cage structure can shrink and rebound when being squeezed by external force, and can reduce the impact of external force on polyurethane film layer, thereby reducing the wear caused by external force, so that it has excellent wear resistance; organosilicon structure has low surface tension and hydrophobicity, is incompatible with hydrocarbon components, tends to migrate to the surface and aggregate in the film forming process, forms organosilicon layers of different levels, so that it has excellent anti-fouling performance, and organosilicon structure migrates to the film surface in the film forming process, and low surface energy is conducive to reducing the friction force during wear, and further improves wear resistance. In addition, the introduced polyacrylic acid segment can form a cross-linked network with polyurethane, enhance the lubricity and protectiveness of polyurethane film layer, reduce the damage of external friction to its structure, and improve wear resistance. The modified polyurethane emulsion for leather of the present invention has good compatibility with the leather surface and is easier to form a polyurethane film layer with good adhesion on the leather surface, thereby playing a better protective role and extending the service life of leather products.

[0014] Preferably, the modified polyurethane emulsion for leather is prepared by the following method:

[0015] 6-10 parts by weight of polymethyl hydrogen siloxane, 3-6 parts by weight of epoxy-terminated allyl polyether and 30-50 parts by weight of ethylene glycol dimethyl ether are mixed, and heated to 90-100° C. at 100-300 r / min in a nitrogen atmosphere with stirring, and then 0.03-0.08 parts by weight of Custer catalyst are added and stirring is continued for 2-4 hours, and ethylene glycol dimethyl ether is removed by reduced pressure distillation to obtain epoxy-terminated polyether modified silicone oil; 3-7 parts by weight of epoxy-terminated polyether modified silicone oil, 6-10 parts by weight of ethylene glycol and 0.04-0.06 parts by weight of p-toluenesulfonic acid are mixed, and heated to 90-100° C. at 100-300 r / min. , stirring and reacting at 85-90°C for 5-8h, removing excess ethylene glycol by reduced pressure distillation to obtain terminal hydroxyl polyether modified silicone oil; mixing 10-15 parts by weight of PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted, 15-20 parts by weight of vinyl silicone oil and 50-80 parts by weight of ethylene glycol dimethyl ether, stirring and heating to 85-95°C at 100-300r / min and nitrogen atmosphere, then adding 0.1-0.3 parts by weight of Custer catalyst and continuing stirring for 4-6h, and removing ethylene glycol dimethyl ether by reduced pressure distillation to obtain terminal hydroxyl POSS modified silicone oil;

[0016] 5-8 parts by weight of hydroxyl-terminated polyether modified silicone oil, 3-6 parts by weight of hydroxyl-terminated POSS modified silicone oil, 10-30 parts by weight of polytetramethylene glycol, 10-30 parts by weight of dicyclohexylmethane-4,4'-diisocyanate, 3-5 parts by weight of 2,2-dihydroxymethylpropionic acid and 0.06-0.1 parts by weight of dibutyltin dilaurate are mixed, stirred at 80-150 r / min and 75-80° C. for 0.5-2 h, then 40-60 parts by weight of polytetramethylene glycol are added to continue the reaction for 1-3 h, and after the reaction is completed, the mixture is cooled to room temperature, and 10-30 parts by weight of N,N- Dimethylformamide, 2-4 parts by weight of ethyl methacrylate and 0.5-1.5 parts by weight of triethylamine are uniformly mixed, stirred and reacted at 80-150 r / min and 60-70° C. for 1-3 hours, then 0.03-0.05 parts by weight of azobisisobutyronitrile are added and stirred for 1-2 hours, and N,N-dimethylformamide is removed by reduced pressure distillation to obtain a modified polyurethane; the modified polyurethane and water are added into a high-speed disperser, the solid content is controlled to be 40-50wt%, and dispersed at a speed of 1000-3000 r / min for 20-50 minutes to obtain the modified polyurethane emulsion for leather.

[0017] Preferably, the defoamer is an organosilicon defoamer, and any one of BYK-035 defoamer, BYK-037 defoamer and BYK-044 defoamer can be selected.

[0018] Preferably, the leveling agent is polyether-modified polydimethylsiloxane, and any one of BYK-333 leveling agent, BYK-331 leveling agent, and BYK-307 leveling agent can be selected.

[0019] Preferably, the wetting agent is a polyether siloxane copolymer, and any one of TEGO-260 wetting agent, TEGO-250 wetting agent, and TEGO-270 wetting agent can be selected.

[0020] Preferably, the thickener is any one of hydroxymethyl cellulose, sodium polyacrylate and hydroxyethyl cellulose.

[0021] Preferably, the film-forming aid is any one of dodecyl alcohol ester (full name: 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), dipropylene glycol butyl ether, and tripropylene glycol butyl ether.

[0022] The invention also provides a method for preparing the wear-resistant and anti-fouling leather surface treatment agent.

[0023] Preferably, a method for preparing a wear-resistant and anti-fouling leather surface treatment agent comprises the following steps:

[0024] The modified polyurethane emulsion for leather, defoamer, leveling agent, wetting agent and water are mixed according to the raw material formula, stirred at a speed of 500-700r / min for 30-40min, and then a thickener and a film-forming aid are added and stirred for 10-20min to obtain the wear-resistant and anti-fouling leather surface treatment agent.

[0025] Beneficial effects of the present invention:

[0026] The wear-resistant and anti-fouling leather surface treatment agent prepared by the present invention uses a modified polyurethane emulsion for leather prepared by reacting terminal hydroxyl polyether modified silicone oil, terminal hydroxyl POSS modified silicone oil, polytetramethylene glycol, dicyclohexylmethane-4,4'-diisocyanate, 2,2-dihydroxymethylpropionic acid, ethyl methacrylate and triethylamine and then dispersing them in water, thereby significantly improving the wear resistance and anti-fouling performance of the leather surface treatment agent, and providing lasting protection for leather products. DETAILED DESCRIPTION

[0027] The following will be combined with the specific embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Polymethyl hydrogen siloxane, hydrogen content is 0.25wt%, viscosity (25℃) is 200mPa.s.

[0029] Epoxy-terminated allyl polyether, average molecular weight 450, epoxy value 0.19eq / 100g, double bond retention rate 90%.

[0030] PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted, CAS: 480439-48-3.

[0031] Vinyl silicone oil, vinyl content 1.06wt%, viscosity (25℃) 100mm 2 / s.

[0032] Polytetramethylene glycol, average molecular weight is 2000.

[0033] Example 1

[0034] A wear-resistant and anti-fouling leather surface treatment agent, comprising the following raw materials in parts by weight:

[0035] 80 parts by weight of modified polyurethane emulsion for leather, 0.5 parts by weight of BYK-035 defoamer, 0.5 parts by weight of BYK-333 leveling agent, 1 part by weight of TEGO-260 wetting agent, 0.5 parts by weight of thickener, 1.5 parts by weight of film-forming aid, and 30 parts by weight of water. The thickener is hydroxymethyl cellulose; the film-forming aid is dodecyl alcohol ester.

[0036] The modified polyurethane emulsion for leather is prepared by the following method:

[0037] 7.5 parts by weight of polymethyl hydrogen siloxane, 4.5 parts by weight of epoxy-terminated allyl polyether and 40 parts by weight of ethylene glycol dimethyl ether were mixed, stirred and heated to 95°C at 200 r / min and nitrogen atmosphere, and then 0.06 parts by weight of Custer catalyst was added and stirred for 3 hours, and ethylene glycol dimethyl ether was removed by vacuum distillation to obtain epoxy-terminated polyether-modified silicone oil; 5 parts by weight of epoxy-terminated polyether-modified silicone oil, 8 parts by weight of ethylene glycol and 0.05 parts by weight of p-toluenesulfonic acid were mixed, and stirred at 200 r / min and 86 ℃, stirring and reacting for 6h, and removing excess ethylene glycol by vacuum distillation to obtain terminal hydroxyl polyether modified silicone oil; 12 parts by weight of PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted, 16 parts by weight of vinyl silicone oil and 60 parts by weight of ethylene glycol dimethyl ether were mixed, stirred and heated to 90℃ at 200r / min and nitrogen atmosphere, and then 0.15 parts by weight of Custer catalyst were added and continued to stir for 5h, and ethylene glycol dimethyl ether was removed by vacuum distillation to obtain terminal hydroxyl POSS modified silicone oil;

[0038] 6 parts by weight of terminal hydroxyl polyether modified silicone oil, 4 parts by weight of terminal hydroxyl POSS modified silicone oil, 20 parts by weight of polytetramethylene glycol, 20 parts by weight of dicyclohexylmethane-4,4'-diisocyanate, 4 parts by weight of 2,2-dihydroxymethyl propionic acid and 0.08 parts by weight of dibutyltin dilaurate were mixed, stirred at 100 r / min and 78° C. for 1 h, then 50 parts by weight of polytetramethylene glycol were added to continue the reaction for 2 h, and after the reaction was completed, the mixture was cooled to room temperature and 20 parts by weight of N,N-dimethyl The invention discloses a method for preparing a modified polyurethane emulsion for leather. The method comprises the following steps: uniformly mixing 1,2-dimethylformamide, 3 parts by weight of ethyl methacrylate and 1 part by weight of triethylamine, stirring and reacting at 100 r / min and 65° C. for 2 h, then adding 0.045 parts by weight of azobisisobutyronitrile and continuing stirring for 1.5 h, and removing N,N-dimethylformamide by reduced pressure distillation to obtain a modified polyurethane; adding the modified polyurethane and water into a high-speed disperser, controlling the solid content to 45wt%, and dispersing at a speed of 2000 r / min for 30 min to obtain the modified polyurethane emulsion for leather.

[0039] A method for preparing a wear-resistant and anti-fouling leather surface treatment agent comprises the following steps:

[0040] According to the raw material formula, the modified polyurethane emulsion for leather, BYK-035 defoamer, BYK-333 leveling agent, TEGO-260 wetting agent and water are mixed, stirred at a speed of 600 r / min for 35 minutes, and then the thickener and film-forming aid are added and stirred for 15 minutes to obtain the wear-resistant and anti-fouling leather surface treatment agent.

[0041] Example 2

[0042] A wear-resistant and anti-fouling leather surface treatment agent, comprising the following raw materials in parts by weight:

[0043] 70 parts by weight of modified polyurethane emulsion for leather, 0.4 parts by weight of BYK-035 defoamer, 0.4 parts by weight of BYK-333 leveling agent, 0.8 parts by weight of TEGO-260 wetting agent, 0.4 parts by weight of thickener, 1.2 parts by weight of film-forming aid, and 20 parts by weight of water. The thickener is hydroxymethyl cellulose; the film-forming aid is dodecyl alcohol ester; the modified polyurethane emulsion for leather is the same as that in Example 1.

[0044] A method for preparing a wear-resistant and anti-fouling leather surface treatment agent comprises the following steps:

[0045] According to the raw material formula, the modified polyurethane emulsion for leather, BYK-035 defoamer, BYK-333 leveling agent, TEGO-260 wetting agent and water are mixed, stirred at a speed of 700 r / min for 30 minutes, and then the thickener and film-forming aid are added and stirred for 20 minutes to obtain the wear-resistant and anti-fouling leather surface treatment agent.

[0046] Example 3

[0047] A wear-resistant and anti-fouling leather surface treatment agent, comprising the following raw materials in parts by weight:

[0048] 90 parts by weight of modified polyurethane emulsion for leather, 0.6 parts by weight of BYK-035 defoamer, 0.6 parts by weight of BYK-333 leveling agent, 1.2 parts by weight of TEGO-260 wetting agent, 0.6 parts by weight of thickener, 1.8 parts by weight of film-forming aid, 40 parts by weight of water. The thickener is hydroxymethyl cellulose; the film-forming aid is dodecyl alcohol ester; the modified polyurethane emulsion for leather is the same as that in Example 1.

[0049] A method for preparing a wear-resistant and anti-fouling leather surface treatment agent comprises the following steps:

[0050] According to the raw material formula, the modified polyurethane emulsion for leather, BYK-035 defoamer, BYK-333 leveling agent, TEGO-260 wetting agent and water are mixed, stirred at a speed of 500 r / min for 40 minutes, and then the thickener and film-forming aid are added and stirred for 10 minutes to obtain the wear-resistant and anti-fouling leather surface treatment agent.

[0051] Example 4

[0052] A wear-resistant and anti-fouling leather surface treatment agent, comprising the following raw materials in parts by weight:

[0053] 80 parts by weight of modified polyurethane emulsion for leather, 0.5 parts by weight of BYK-035 defoamer, 0.5 parts by weight of BYK-333 leveling agent, 1 part by weight of TEGO-260 wetting agent, 0.5 parts by weight of thickener, 1.5 parts by weight of film-forming aid, and 30 parts by weight of water. The thickener is hydroxymethyl cellulose; the film-forming aid is dodecyl alcohol ester.

[0054] The modified polyurethane emulsion for leather is prepared by the following method:

[0055] 7.5 parts by weight of polymethyl hydrogen siloxane, 4.5 parts by weight of epoxy-terminated allyl polyether and 40 parts by weight of ethylene glycol dimethyl ether were mixed, stirred and heated to 95° C. at 200 r / min in a nitrogen atmosphere, and then 0.06 parts by weight of Custer catalyst was added and continued to be stirred for 3 hours, and ethylene glycol dimethyl ether was removed by reduced pressure distillation to obtain epoxy-terminated polyether modified silicone oil; 5 parts by weight of epoxy-terminated polyether modified silicone oil, 8 parts by weight of ethylene glycol and 0.05 parts by weight of p-toluenesulfonic acid were mixed, stirred and reacted at 200 r / min and 86° C. for 6 hours, and excess ethylene glycol was removed by reduced pressure distillation to obtain hydroxyl-terminated polyether modified silicone oil;

[0056] 10 parts by weight of hydroxyl-terminated polyether modified silicone oil, 20 parts by weight of polytetramethylene glycol, 20 parts by weight of dicyclohexylmethane-4,4'-diisocyanate, 4 parts by weight of 2,2-dihydroxymethylpropionic acid and 0.08 parts by weight of dibutyltin dilaurate were mixed, stirred at 100 r / min and 78° C. for 1 h, then 50 parts by weight of polytetramethylene glycol were added and the reaction was continued for 2 h. After the reaction was completed, the mixture was cooled to room temperature, and 20 parts by weight of N,N-dimethylformamide, 3 parts by weight of butyltin dilaurate were added. 1 part by weight of ethyl methacrylate and 1 part by weight of triethylamine are uniformly mixed, stirred and reacted at 100 r / min and 65° C. for 2 h, then 0.045 part by weight of azobisisobutyronitrile is added and stirring is continued for 1.5 h, and N,N-dimethylformamide is removed by reduced pressure distillation to obtain a modified polyurethane; the modified polyurethane and water are added to a high-speed disperser, the solid content is controlled to be 45wt%, and dispersed at a speed of 2000 r / min for 30 min to obtain the modified polyurethane emulsion for leather.

[0057] A method for preparing a wear-resistant and anti-fouling leather surface treatment agent comprises the following steps:

[0058] According to the raw material formula, the modified polyurethane emulsion for leather, BYK-035 defoamer, BYK-333 leveling agent, TEGO-260 wetting agent and water are mixed, stirred at a speed of 600 r / min for 35 minutes, and then the thickener and film-forming aid are added and stirred for 15 minutes to obtain the wear-resistant and anti-fouling leather surface treatment agent.

[0059] Example 5

[0060] A wear-resistant and anti-fouling leather surface treatment agent, comprising the following raw materials in parts by weight:

[0061] 80 parts by weight of modified polyurethane emulsion for leather, 0.5 parts by weight of BYK-035 defoamer, 0.5 parts by weight of BYK-333 leveling agent, 1 part by weight of TEGO-260 wetting agent, 0.5 parts by weight of thickener, 1.5 parts by weight of film-forming aid, and 30 parts by weight of water. The thickener is hydroxymethyl cellulose; the film-forming aid is dodecyl alcohol ester.

[0062] The modified polyurethane emulsion for leather is prepared by the following method:

[0063] 12 parts by weight of PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted, 16 parts by weight of vinyl silicone oil and 60 parts by weight of ethylene glycol dimethyl ether were mixed, stirred and heated to 90° C. at 200 r / min in a nitrogen atmosphere, then 0.15 parts by weight of Custer catalyst was added and continued to stir for 5 hours, and ethylene glycol dimethyl ether was removed by distillation under reduced pressure to obtain hydroxyl-terminated POSS modified silicone oil;

[0064] 10 parts by weight of terminal hydroxyl POSS modified silicone oil, 20 parts by weight of polytetramethylene glycol, 20 parts by weight of dicyclohexylmethane-4,4'-diisocyanate, 4 parts by weight of 2,2-dihydroxymethylpropionic acid and 0.08 parts by weight of dibutyltin dilaurate were mixed, stirred at 100 r / min and 78° C. for 1 h, then 50 parts by weight of polytetramethylene glycol were added and the reaction was continued for 2 h. After the reaction was completed, the mixture was cooled to room temperature, and 20 parts by weight of N,N-dimethylformamide, 3 Parts by weight of ethyl methacrylate and 1 part by weight of triethylamine are uniformly mixed, stirred and reacted at 100 r / min and 65° C. for 2 hours, 0.045 parts by weight of azobisisobutyronitrile are added and stirring is continued for 1.5 hours, and N,N-dimethylformamide is removed by reduced pressure distillation to obtain a modified polyurethane; the modified polyurethane and water are added to a high-speed disperser, the solid content is controlled to be 45wt%, and dispersed at a speed of 2000 r / min for 30 minutes to obtain the modified polyurethane emulsion for leather.

[0065] A method for preparing a wear-resistant and anti-fouling leather surface treatment agent comprises the following steps:

[0066] According to the raw material formula, the modified polyurethane emulsion for leather, BYK-035 defoamer, BYK-333 leveling agent, TEGO-260 wetting agent and water are mixed, stirred at a speed of 600 r / min for 35 minutes, and then the thickener and film-forming aid are added and stirred for 15 minutes to obtain the wear-resistant and anti-fouling leather surface treatment agent.

[0067] Example 6

[0068] A wear-resistant and anti-fouling leather surface treatment agent, comprising the following raw materials in parts by weight:

[0069] 80 parts by weight of modified polyurethane emulsion for leather, 0.5 parts by weight of BYK-035 defoamer, 0.5 parts by weight of BYK-333 leveling agent, 1 part by weight of TEGO-260 wetting agent, 0.5 parts by weight of thickener, 1.5 parts by weight of film-forming aid, and 30 parts by weight of water. The thickener is hydroxymethyl cellulose; the film-forming aid is dodecyl alcohol ester.

[0070] The modified polyurethane emulsion for leather is prepared by the following method:

[0071] 6 parts by weight of polymethyl hydrogen siloxane, 4 parts by weight of vinyl silicone oil, 20 parts by weight of polytetramethylene glycol, 20 parts by weight of dicyclohexylmethane-4,4'-diisocyanate, 4 parts by weight of 2,2-dihydroxymethyl propionic acid and 0.08 parts by weight of dibutyltin dilaurate were mixed, stirred at 100 r / min and 78°C for 1 hour, then 50 parts by weight of polytetramethylene glycol were added and the reaction was continued for 2 hours. After the reaction was completed, the mixture was cooled to room temperature and 20 parts by weight of N,N-dimethylformamide were added. , 3 parts by weight of ethyl methacrylate and 1 part by weight of triethylamine are uniformly mixed, the reaction is stirred at 100 r / min and 65°C for 2 hours, 0.045 parts by weight of azobisisobutyronitrile is added and the stirring is continued for 1.5 hours, and N,N-dimethylformamide is removed by reduced pressure distillation to obtain a modified polyurethane; the modified polyurethane and water are added into a high-speed disperser, the solid content is controlled to be 45wt%, and the mixture is dispersed at a speed of 2000 r / min for 30 minutes to obtain the modified polyurethane emulsion for leather.

[0072] A method for preparing a wear-resistant and anti-fouling leather surface treatment agent comprises the following steps:

[0073] According to the raw material formula, the modified polyurethane emulsion for leather, BYK-035 defoamer, BYK-333 leveling agent, TEGO-260 wetting agent and water are mixed, stirred at a speed of 600 r / min for 35 minutes, and then the thickener and film-forming aid are added and stirred for 15 minutes to obtain the wear-resistant and anti-fouling leather surface treatment agent.

[0074] Example 7

[0075] A wear-resistant and anti-fouling leather surface treatment agent, comprising the following raw materials in parts by weight:

[0076] 80 parts by weight of modified polyurethane emulsion for leather, 0.5 parts by weight of BYK-035 defoamer, 0.5 parts by weight of BYK-333 leveling agent, 1 part by weight of TEGO-260 wetting agent, 0.5 parts by weight of thickener, 1.5 parts by weight of film-forming aid, and 30 parts by weight of water. The thickener is hydroxymethyl cellulose; the film-forming aid is dodecyl alcohol ester.

[0077] The modified polyurethane emulsion for leather is prepared by the following method:

[0078] 7.5 parts by weight of polymethyl hydrogen siloxane, 4.5 parts by weight of epoxy-terminated allyl polyether and 40 parts by weight of ethylene glycol dimethyl ether were mixed, stirred and heated to 95°C at 200 r / min and nitrogen atmosphere, and then 0.06 parts by weight of Custer catalyst was added and stirred for 3 hours, and ethylene glycol dimethyl ether was removed by vacuum distillation to obtain epoxy-terminated polyether-modified silicone oil; 5 parts by weight of epoxy-terminated polyether-modified silicone oil, 8 parts by weight of ethylene glycol and 0.05 parts by weight of p-toluenesulfonic acid were mixed, and stirred at 200 r / min and 86 ℃, stirring and reacting for 6h, and removing excess ethylene glycol by vacuum distillation to obtain terminal hydroxyl polyether modified silicone oil; 12 parts by weight of PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted, 16 parts by weight of vinyl silicone oil and 60 parts by weight of ethylene glycol dimethyl ether were mixed, stirred and heated to 90℃ at 200r / min and nitrogen atmosphere, and then 0.15 parts by weight of Custer catalyst were added and continued to stir for 5h, and ethylene glycol dimethyl ether was removed by vacuum distillation to obtain terminal hydroxyl POSS modified silicone oil;

[0079] 6 parts by weight of terminal hydroxyl polyether modified silicone oil, 4 parts by weight of terminal hydroxyl POSS modified silicone oil, 20 parts by weight of polytetramethylene ether diol, 20 parts by weight of dicyclohexylmethane-4,4'-diisocyanate and 0.08 parts by weight of dibutyltin dilaurate are mixed, stirred and reacted at 100 r / min and 78°C for 1 hour, and then 50 parts by weight of polytetramethylene ether diol are added and the reaction is continued for 2 hours to obtain modified polyurethane; the modified polyurethane and water are added into a high-speed disperser, the solid content is controlled to be 45wt%, and dispersed at a speed of 2000 r / min for 30 minutes to obtain the modified polyurethane emulsion for leather.

[0080] A method for preparing a wear-resistant and anti-fouling leather surface treatment agent comprises the following steps:

[0081] According to the raw material formula, the modified polyurethane emulsion for leather, BYK-035 defoamer, BYK-333 leveling agent, TEGO-260 wetting agent and water are mixed, stirred at a speed of 600 r / min for 35 minutes, and then the thickener and film-forming aid are added and stirred for 15 minutes to obtain the wear-resistant and anti-fouling leather surface treatment agent.

[0082] The wear-resistant and anti-fouling leather surface treatment agent prepared in the above embodiment is evenly coated on the top layer of cowhide leather and cured at 130°C for 10 minutes to obtain a leather sample (the coating layer thickness is 1 mm). The leather sample is tested for its anti-fouling properties against oil-based pens, water-based pens, and olive oil. The specific method is as follows: (1) Use an oil-based pen and a water-based pen to draw a straight line of the same length on the surface of the leather sample, and observe whether the mark can be completely erased; if no stain remains after erasure, it passes. (2) Use an equal amount of olive oil to apply to the surface of the leather sample, and observe whether the olive oil can be completely erased; if no stain remains after erasure, it passes.

[0083] Table 1. Antifouling performance test results of leather surface treatment agents

[0084]

[0085] Test Example 2

[0086] The wear-resistant and anti-fouling leather surface treatment agent prepared in the above embodiment is evenly coated on the top layer of cowhide leather, cured at 130°C for 10 minutes, and a leather sample (coating layer thickness is 1 mm) is obtained. The wear resistance of the above leather sample is measured by a Martindale abrasion tester, the abrasive is 400 mesh sandpaper, and the load is 100g. Record the number of frictions corresponding to the beginning of powder loss. The greater the number of frictions, the better the wear resistance. The above leather sample is subjected to a folding test according to the reference standard QB / T 2714-2018. The leather sample is folded, removed and observed every 1,000 times, and the number of times obvious damage occurs is recorded. The greater the number of foldings, the better the performance.

[0087] Table 2. Test results of abrasion resistance and folding resistance of leather surface treatment agents

[0088]

[0089] From the above test results, it can be seen that the leather surface treatment agents prepared in Examples 1-3 of the present invention have excellent anti-fouling performance, wear resistance and folding resistance. In comparison, Examples 4-7 did not adopt the necessary technical solutions, resulting in relatively poor test results of their related properties. The leather modified polyurethane emulsion adopted in the embodiment of the present invention 1-3, it is successfully introduced into the polyurethane main chain by terminal hydroxyl polyether modified silicone oil and terminal hydroxyl POSS modified silicone oil as monomer by polyether structure, cage structure and organosilicon structure, polyether structure can improve the flexibility and wear resistance of polyurethane as soft segment;Cage structure can shrink and rebound when being squeezed by external force, can reduce the impact of external force on polyurethane film layer, thereby reducing the wear caused by external force, so that it has excellent wear resistance;Organosilicon structure has low surface tension and hydrophobicity, is incompatible with hydrocarbon components, tends to migrate to the surface and aggregate in film forming process, forms organosilicon layers of different levels, so that it has excellent anti-fouling performance, while organosilicon structure migrates to the film surface in film forming process, low surface energy is conducive to reducing the friction force during wear, further improves wear resistance. In addition, introducing polyacrylic acid segment can form a cross-linked network with polyurethane, enhances the lubricity and protectiveness of polyurethane film layer, reduces the damage of external friction to its structure, and improves wear resistance.

[0090] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A wear-resistant and anti-fouling leather surface treatment agent, characterized in that: Made from the following ingredients: Modified polyurethane emulsion for leather, defoamer, leveling agent, wetting agent, thickener, film-forming aid, water; The modified polyurethane emulsion for leather is prepared by the following method: The polymethyl hydrogen siloxane, the epoxy-terminated allyl polyether and ethylene glycol dimethyl ether are mixed, stirred and heated under a nitrogen atmosphere, and then a Custer catalyst is added and stirred continuously, and distilled under reduced pressure to obtain an epoxy-terminated polyether modified silicone oil; the epoxy-terminated polyether modified silicone oil, ethylene glycol and p-toluenesulfonic acid are mixed, heated and stirred for reaction, and distilled under reduced pressure to obtain a hydroxyl-terminated polyether modified silicone oil; PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted, vinyl silicone oil and ethylene glycol dimethyl ether are mixed, stirred and heated under a nitrogen atmosphere, and then a Custer catalyst is added and stirred continuously, and distilled under reduced pressure to obtain a hydroxyl-terminated POSS modified silicone oil; The terminal hydroxyl polyether modified silicone oil, the terminal hydroxyl POSS modified silicone oil, polytetramethylene glycol, dicyclohexylmethane-4,4'-diisocyanate, 2,2-dihydroxymethyl propionic acid and dibutyltin dilaurate are mixed, heated and stirred for reaction, and then the polytetramethylene glycol is added to continue the reaction, and after the reaction is completed, the mixture is cooled, and N,N-dimethylformamide, ethyl methacrylate and triethylamine are added to mix evenly, heated and stirred for reaction, and then azobisisobutyronitrile is added to continue stirring, and reduced pressure distillation is performed to obtain modified polyurethane; the modified polyurethane and water are added to a high-speed disperser for dispersion to obtain the modified polyurethane emulsion for leather.

2. The wear-resistant and anti-fouling leather surface treating agent according to claim 1, characterized in that: The invention is made of the following raw materials in parts by weight: 70-90 parts by weight of modified polyurethane emulsion for leather, 0.4-0.6 parts by weight of defoamer, 0.4-0.6 parts by weight of leveling agent, 0.8-1.2 parts by weight of wetting agent, 0.4-0.6 parts by weight of thickener, 1.2-1.8 parts by weight of film-forming aid, and 20-40 parts by weight of water.

3. The wear-resistant and anti-fouling leather surface treating agent according to claim 1, characterized in that: The modified polyurethane emulsion for leather is prepared by the following method: 6-10 parts by weight of polymethyl hydrogen siloxane, 3-6 parts by weight of epoxy-terminated allyl polyether and 30-50 parts by weight of ethylene glycol dimethyl ether are mixed, heated to 90-100° C. under a nitrogen atmosphere with stirring, then 0.03-0.08 parts by weight of Custer catalyst is added, stirring is continued, and distillation is performed under reduced pressure to obtain epoxy-terminated polyether-modified silicone oil; 3-7 parts by weight of epoxy-terminated polyether-modified silicone oil, 6-10 parts by weight of ethylene glycol and 0.04-0.06 parts by weight of p-toluenesulfonic acid are mixed, The reaction was stirred at 85-90° C., and vacuum distillation was performed to obtain a hydroxyl-terminated polyether-modified silicone oil; 10-15 parts by weight of PSS-(2-(trans-3,4-cyclohexanediol)ethyl)-heptaisobutyl substituted, 15-20 parts by weight of vinyl silicone oil and 50-80 parts by weight of ethylene glycol dimethyl ether were mixed, and the mixture was stirred and heated to 85-95° C. under a nitrogen atmosphere, and then 0.1-0.3 parts by weight of Custer catalyst was added, and the mixture was continuously stirred and vacuum distillation was performed to obtain a hydroxyl-terminated POSS-modified silicone oil; 5-8 parts by weight of terminal hydroxyl polyether modified silicone oil, 3-6 parts by weight of terminal hydroxyl POSS modified silicone oil, 10-30 parts by weight of polytetramethylene glycol, 10-30 parts by weight of dicyclohexylmethane-4,4'-diisocyanate, 3-5 parts by weight of 2,2-dimethylol propionic acid and 0.06-0.1 parts by weight of dibutyltin dilaurate are mixed, stirred and reacted at 75-80° C., then 40-60 parts by weight of polytetramethylene glycol are added to continue the reaction, and then cooled after the reaction is completed. 10-30 parts by weight of N,N-dimethylformamide, 2-4 parts by weight of ethyl methacrylate and 0.5-1.5 parts by weight of triethylamine are added and mixed evenly, stirred and reacted at 60-70° C., and then 0.03-0.05 parts by weight of azobisisobutyronitrile are added and stirred continuously, and distilled under reduced pressure to obtain modified polyurethane; the modified polyurethane and water are added into a high-speed disperser, and dispersed at a speed of 1000-3000 r / min to obtain the modified polyurethane emulsion for leather.

4. The wear-resistant and anti-fouling leather surface treating agent according to claim 1, characterized in that: The defoamer is an organosilicon defoamer; the organosilicon defoamer is any one of BYK-035 defoamer, BYK-037 defoamer and BYK-044 defoamer.

5. The wear-resistant and anti-fouling leather surface treating agent according to claim 1, characterized in that: The leveling agent is polyether-modified polydimethylsiloxane; the polyether-modified polydimethylsiloxane is any one of BYK-333 leveling agent, BYK-331 leveling agent and BYK-307 leveling agent.

6. The wear-resistant and anti-fouling leather surface treating agent according to claim 1, characterized in that: The wetting agent is a polyether siloxane copolymer, and the polyether siloxane copolymer is any one of TEGO-260 wetting agent, TEGO-250 wetting agent, and TEGO-270 wetting agent.

7. The wear-resistant and anti-fouling leather surface treating agent according to claim 1, characterized in that: The thickener is any one of hydroxymethyl cellulose, sodium polyacrylate and hydroxyethyl cellulose.

8. The wear-resistant and anti-fouling leather surface treating agent according to claim 1, characterized in that: The film-forming aid is any one of dodecyl alcohol ester, dipropylene glycol butyl ether and tripropylene glycol butyl ether.

9. The method for preparing the wear-resistant and anti-fouling leather surface treatment agent according to any one of claims 1 to 8, characterized in that: The following steps are involved: The modified polyurethane emulsion for leather, defoamer, leveling agent, wetting agent and water are mixed according to the raw material formula, stirred at a speed of 500-700r / min for 30-40min, and then a thickener and a film-forming aid are added and stirred for 10-20min to obtain the wear-resistant and anti-fouling leather surface treatment agent.

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