CN-121975420-A - High-performance light-coated leather brightening agent and preparation method thereof

CN121975420ACN 121975420 ACN121975420 ACN 121975420ACN-121975420-A

Abstract

The invention provides a high-performance light-coating leather brightening agent and a preparation method thereof, belonging to the technical field of leather finishing materials. The high-performance light-coated leather brightening agent provided by the invention remarkably improves the visual matte effect and the touch softness of the coating while maintaining the physical properties of the traditional polyurethane brightening agent such as excellent light resistance, abrasion resistance, color fastness and the like, and realizes the unification of high performance and comfortable hand feeling. The product is suitable for coating various high-grade leather products, can meet the comprehensive requirements of modern consumers on the appearance, the handfeel and the durability of leather, and promotes the development of leather coating materials to the high-performance and high-sensory experience direction.

Inventors

HE XIANXIAN
GAO WEI
ZHU YANGSHENG
YANG SISHENG

Assignees

上海金狮化工有限公司

Dates

Publication Date: 20260505
Application Date: 20260208

Claims (10)

1. The high-performance light-coating leather brightening agent is characterized by comprising the following raw materials in parts by weight: 40-50 parts of self-extinction polyurethane resin, 10-15 parts of silicon modified polyurethane resin, 10-15 parts of medium soft polyurethane resin and 20-40 parts of water.
2. The high performance light-coated leather brightener of claim 1 wherein said self-extinction polyurethane resin is a polyether self-extinction polyurethane resin; The silicon content of the silicon-modified polyurethane resin is more than 50%; The medium soft polyurethane resin is a carbon-rich medium soft polyurethane resin.
3. The high-performance light-coated leather brightening agent according to claim 1 or 2, further comprising 0.1-1 part of wetting leveling agent; 0.1-0.5 parts of preservative; 0.1-0.5 part of pH regulator; 1-3 parts of a thickener.
4. The high performance light-coated leather brightener of claim 3 wherein said wetting and leveling agent is a silicone leveling agent; The preservative is an isothiazolinone preservative; The pH regulator is an amine pH regulator; the thickener is at least one selected from acrylic thickener, polyurethane thickener and inorganic anti-settling agent.
5. The method for preparing the high-performance light-coated leather brightening agent according to any one of claims 1 to 4, which is characterized by comprising the following steps: Mixing deionized water and a wetting leveling agent; adding self-extinction polyurethane resin and uniformly stirring; Adding silicon modified polyurethane resin and medium soft polyurethane resin and uniformly stirring; Adding a pH regulator to regulate the pH value of the system; and adding a thickening agent to regulate the viscosity and filtering to obtain the high-performance light-coated leather brightening agent.
6. The method according to claim 5, wherein in the step of adding the self-extinction polyurethane resin and stirring uniformly, the stirring speed is 400-600 rpm, and the stirring is continued until the mixed system is uniform and no obvious granular sensation is generated; Before the silicon modified polyurethane resin and the medium soft polyurethane resin are added, the method further comprises the step of vacuum defoaming the mixed solution.
7. The method according to claim 5, wherein the pH regulator is used for regulating the pH value of the system to 8-9.
8. The method according to claim 5, wherein in the step of adding a thickener to adjust the viscosity, the viscosity of the final product is adjusted to 1000 to 2000 cps.
9. The method of claim 5, wherein the self-extinction polyurethane resin is prepared by a method comprising: Reacting polyether polyol and aliphatic diisocyanate at 80-90 ℃ for 2-3 hours in the presence of a catalyst to obtain a prepolymer; cooling the prepolymer to 60-70 ℃, and then adding a hydrophilic chain extender to react for 1-2 hours; adding deionized water for emulsification after neutralization, and then adding a small molecular chain extender for post chain extension and curing to obtain polyurethane emulsion containing spherical extinction particles; Wherein the polyether polyol is selected from at least one of polytetrahydrofuran polyol or polyoxypropylene ether polyol; the catalyst is at least one selected from organobismuth catalysts, organozirconium catalysts and organozinc catalysts; the hydrophilic chain extender is at least one selected from dimethylolpropionic acid, dimethylolbutyric acid or polyethylene glycol; The small molecule chain extender is selected from at least one of ethylene glycol, triethanolamine, ethylenediamine, diethylenetriamine or triethylenetetramine.
10. A method of finishing leather comprising the steps of: Spraying a leather blank with the high-performance lightly coated leather brightener according to claims 1-4 or prepared by the preparation method according to any one of claims 5-9.

Description

High-performance light-coated leather brightening agent and preparation method thereof Technical Field The invention relates to the technical field of leather finishing materials, in particular to a high-performance light-coating leather brightening agent and a preparation method thereof. Background Leather finishing is a key element in the leather processing process, and the appearance, hand feel, durability and special performance of leather are improved mainly by applying finishing agents. The finish system typically includes a base layer, a middle layer, and a top layer, wherein the top layer finish (often referred to as a polish or top layer treatment) directly affects the final gloss, feel, abrasion resistance, chemical resistance, etc. properties of the leather. The traditional leather brightening agent mainly comprises casein, nitrocotton and synthetic resin. The casein brightening agent is environment-friendly, natural in hand feeling, poor in water resistance and mechanical strength, good in luster, quick in drying, poor in weather resistance and easy to yellow, and synthetic resins (especially polyurethanes) are mainstream choices due to the excellent film forming property, wear resistance and chemical resistance. With the development of aqueous polyurethane technology, environment-friendly brightening agents gradually replace solvent-based products, but in practical application, an aqueous system is difficult to achieve light and soft light coating feel while maintaining high performance. Most high-performance brightening agent coatings on the current market are hard, but products with soft hand feeling often have insufficient wear resistance, scratch resistance and the like, Therefore, development of an aqueous brightening agent that satisfies the requirements of high-end physical properties and provides a comfortable and light coating feel has been a technical problem to be solved in the art. Disclosure of Invention The invention aims to provide a high-performance light-coating leather brightening agent and a preparation method thereof, and solves the problem that the existing leather brightening agent cannot meet the requirements of excellent physical and mechanical properties (such as light resistance, wear resistance and color fastness) and soft and comfortable light-coating hand feeling. In order to achieve the above object, the present invention provides the following technical solutions: the invention provides a high-performance light-coating leather brightening agent, which comprises the following raw materials in parts by weight: 40-50 parts of self-extinction polyurethane resin, 10-15 parts of silicon modified polyurethane resin, 10-15 parts of medium soft polyurethane resin and 20-40 parts of water. Preferably, the self-extinction polyurethane resin is polyether type self-extinction polyurethane resin; The silicon content of the silicon-modified polyurethane resin is more than 50%; The medium soft polyurethane resin is a carbon-rich medium soft polyurethane resin. Preferably, the paint further comprises 0.1-1 part of wetting and leveling agent; 0.1-0.5 parts of preservative; 0.1-0.5 part of pH regulator; 1-3 parts of a thickener. Preferably, the wetting leveling agent is an organosilicon leveling agent; The preservative is an isothiazolinone preservative; The pH regulator is an amine pH regulator; the thickener is at least one selected from acrylic thickener, polyurethane thickener and inorganic anti-settling agent. The invention also provides a preparation method of the high-performance light-coating leather brightening agent, which comprises the following steps: Mixing deionized water and a wetting leveling agent; adding self-extinction polyurethane resin and uniformly stirring; Adding silicon modified polyurethane resin and medium soft polyurethane resin and uniformly stirring; Adding a pH regulator to regulate the pH value of the system; and adding a thickening agent to regulate the viscosity and filtering to obtain the high-performance light-coated leather brightening agent. Preferably, in the step of adding the self-extinction polyurethane resin and stirring uniformly, the stirring speed is 400-600 revolutions per minute, and the stirring is continued until the mixed system is uniform and no obvious granular feel exists; Before the silicon modified polyurethane resin and the medium soft polyurethane resin are added, the method further comprises the step of vacuum defoaming the mixed solution. Preferably, the pH regulator is used for regulating the pH value of the system to 8-9. Preferably, in the step of adding the thickener to adjust the viscosity, the viscosity of the final product is adjusted to 1000-2000 centipoise. Preferably, the self-extinction polyurethane resin is prepared by a preparation method comprising the following steps: Reacting polyether polyol and aliphatic diisocyanate at 80-90 ℃ for 2-3 hours in the presence of a catalyst to obtain a prepolymer; cooling the