阅读说明：本技术 共混改性易去污皮革的制备工艺 (Preparation process of blending modified easy-to-clean leather ) 是由 王林云 刘明 刘小平 于 2021-09-26 设计创作，主要内容包括：本发明涉及一种共混改性易去污皮革的制备工艺,具体步骤如下,a.将改性聚氨酯混合浆料涂覆在离型纸上形成面层；b.将聚氨酯混合浆料涂覆在离型纸上形成聚氨酯过渡层；c.再将环保型高固含聚氨酯浆料涂覆再已经干燥的聚氨酯过渡层上形成高固含聚氨酯浆料层；d.将超细纤维织布重叠在高固含聚氨酯浆料层上面,再经过压辊挤压复合；e.经烘箱烘烤；f.经过冷却轮冷却至常温,将皮革和离型纸分离,得到合成革。优点是无需凹版印刷方式,采用改性聚氨酯树脂进行内添加方式,相容性好,不分离,析出好。(The invention relates to a preparation process of blending modified soil-release leather, which comprises the following specific steps of a, coating modified polyurethane mixed slurry on release paper to form a surface layer; b. coating the polyurethane mixed slurry on release paper to form a polyurethane transition layer; c. coating the environment-friendly high-solid-content polyurethane slurry on the dried polyurethane transition layer to form a high-solid-content polyurethane slurry layer; d. overlapping the superfine fiber woven fabric on the high-solid-content polyurethane slurry layer, and extruding and compounding by a compression roller; e. baking in an oven; f. and cooling to normal temperature through a cooling wheel, and separating the leather from the release paper to obtain the synthetic leather. The method has the advantages that a gravure printing mode is not needed, the modified polyurethane resin is adopted for internal addition, the compatibility is good, the separation is not generated, and the precipitation is good.)

1. A preparation process of blending modified soil-release leather is characterized by comprising the following steps,

a. coating the modified polyurethane mixed slurry on release paper, drying for 2-3 minutes at 80-100 ℃, wherein the coating amount is 100-120 g per square meter, and forming a surface layer; the modified polyurethane mixed slurry comprises the following components in parts by weight: modified polyurethane resin: 100 parts by mass of a leveling agent: 0.3-0.5 mass part, 1-3 mass parts of aliphatic NCO prepolymer, 0.1-0.2 mass part of defoaming agent and 0.8-1.5 mass part of antibacterial agent;

b. coating the polyurethane mixed slurry on release paper, drying for 2-3 minutes at 90-100 ℃, wherein the coating amount is 120-140 g per square meter, and forming a polyurethane transition layer; the polyurethane mixed slurry, wherein: polyurethane resin: 100 parts by mass of color paste: 4-15 parts by mass of a leveling agent: 0.3-0.5 mass part, 1-3 mass parts of aliphatic NCO prepolymer and 0.1-0.2 mass part of defoaming agent;

c. coating the environment-friendly high-solid-content polyurethane slurry on the dried polyurethane transition layer, baking for 1-1.5 minutes at the temperature of 120-;

d. c, overlapping the superfine fiber woven fabric with the thickness of 0.8-0.9mm on the high-solid-content polyurethane slurry layer obtained in the step C, and extruding and compounding by using a compression roller, wherein the pressure of the compression roller is 0.2-0.3 MPa;

e. baking the mixture for 5 to 7 minutes in an oven at the temperature of 130 ℃ and 145 ℃;

f. cooling to normal temperature through a cooling wheel, and separating the leather from the release paper to obtain the superfine fiber synthetic leather which is high temperature resistant, easy to clean and antibacterial.

2. The preparation process of the blended modified soil release leather as claimed in claim 1, wherein the environment-friendly high solid content polyurethane slurry comprises: high solid content polyurethane: 100 parts by mass, 0.7-1.4 parts by mass of amine curing agent, 2-3 parts by mass of dichloromethane and 5-10 parts by mass of methyl acetate.

3. The preparation process of the blended modified soil-release leather according to claim 1, wherein the preparation method of the modified polyurethane resin comprises the following steps:

1) firstly, 100 parts by mass of one or two polyurethane resins of polyester, polyether or polycarbonate type with the solid content of 20-50 percent is heated to 70-90 ℃, the viscosity of the system is reduced,

2) respectively and slowly dripping 2-4 parts by mass of di-and tri-functional isocyanate curing agent with NCO content of 6-9% and 0.5-3 parts by mass of hydroxyl polyether modified siloxane with hydroxyl value content of 20-70mgKOH/g into polyurethane resin;

3) and (3) after the dropwise addition is finished, keeping the temperature and stirring for 30-60min to obtain the modified polyurethane resin.

4. The preparation process of the blending modified soil-release leather according to claim 1, wherein the leather prepared by the preparation process of the blending modified soil-release leather comprises a surface layer, a polyurethane transition layer, a high solid content polyurethane layer and a superfine fiber woven fabric layer, wherein the surface layer, the polyurethane transition layer, the high solid content polyurethane layer and the superfine fiber woven fabric layer are sequentially overlapped and compounded together from top to bottom to form a whole, and the surface layer is the modified polyurethane layer.

Technical Field

The invention relates to the field of leather production, in particular to a preparation process of blending modified soil-release leather.

Background

Leather products are widely used in daily life, and various chemical reagents used in the manufacturing process of leather products with the highest grade can cause great pollution to the environment and do not meet the requirement of environmental protection; the leather has irregular shape, more surface flaws, low utilization rate and high use cost for customers; superfine fiber leather is gradually replacing traditional polyvinyl chloride and wet polyurethane leather, and is the closest product to genuine leather at present; the common synthetic leather is produced by adopting thermoplastic polyurethane, and the heat resistance and the maintainability of the common synthetic leather cannot meet the use requirements of some public places. In order to provide the leather surface with a decontamination effect, the decontamination is realized by gravure printing in the prior art, a coating agent of two-component doodle-proof acrylic acid is transferred on the surface of the leather surface resin, the production efficiency is low, the cost is high, the hardness of the coating agent is high, the elongation is low, the overall softness and texture of the product are influenced, and the coating agent cannot be applied to the leather surface with high elongation. At present, the coating agent is coated on the surface of leather by adopting an internal addition coating mode, but the coating agent has poor compatibility with resin, and the problems of phase separation, precipitation and the like are easy to occur. The common polyurethane resin has no effects of doodling prevention, adhesion prevention, water prevention and the like.

Disclosure of Invention

In order to solve the technical problems, the invention provides a preparation process of blending modified easy-to-clean leather, which is novel in process, free of a gravure printing mode, good in compatibility and free of separation and precipitation by adopting a modified polyurethane resin internal addition mode.

The technical scheme of the invention is as follows:

a preparation process of blending modified easy-cleaning leather, which comprises the following steps,

a. coating the modified polyurethane mixed slurry on release paper, drying for 2-3 minutes at 80-100 ℃, wherein the coating amount is 100-120 g per square meter, and forming a surface layer; the modified polyurethane mixed slurry comprises the following components in parts by weight: modified polyurethane resin: 100 parts by mass of a leveling agent: 0.3-0.5 mass part, 1-3 mass parts of aliphatic NCO prepolymer, 0.1-0.2 mass part of defoaming agent and 0.8-1.5 mass part of mildew preventive.

b. Coating the polyurethane mixed slurry on release paper, drying for 2-3 minutes at 90-100 ℃, wherein the coating amount is 120-140 g per square meter, and forming a polyurethane transition layer; the polyurethane mixed slurry, wherein: polyurethane resin: 100 parts by mass of color paste: 4-12 parts by mass of a leveling agent: 0.3-0.5 part by mass, 1-3 parts by mass of aliphatic NCO prepolymer and 0.1-0.2 part by mass of defoaming agent.

c. And then coating the environment-friendly high-solid-content polyurethane slurry on the dried polyurethane transition layer, baking at the temperature of 120-130 ℃ for 1-1.5 minutes, and coating the polyurethane slurry with the coating amount of 180-220 g/square meter to form a high-solid-content polyurethane slurry layer.

d. And C, overlapping the superfine fiber woven cloth with the thickness of 0.8-0.9mm on the high-solid-content polyurethane slurry layer obtained in the step C, and extruding and compounding by using a compression roller, wherein the pressure of the compression roller is 0.2-0.3 MPa.

e. Baking the mixture for 5 to 7 minutes in an oven at the temperature of 130 ℃ and 145 ℃.

f. Cooling to normal temperature through a cooling wheel, and separating the leather from the release paper to obtain the superfine fiber synthetic leather which is high temperature resistant, easy to clean and antibacterial.

The environment-friendly high-solid-content polyurethane slurry comprises the following components: high solid content polyurethane: 100 parts by mass, 0.7-1.4 parts by mass of amine curing agent, 2-3 parts by mass of dichloromethane and 5-10 parts by mass of methyl acetate.

The preparation method of the modified polyurethane resin comprises the following steps:

1) firstly, 100 parts by mass of one or two of polyester, polyether or polycarbonate type polyurethane resin with the solid content of 20-50% is heated to 70-90 ℃, and the viscosity of the system is reduced.

2) Respectively and slowly dripping 2-4 parts by mass of di-and tri-functional isocyanate curing agent with NCO content of 6-9% and 0.5-3 parts by mass of hydroxyl polyether modified siloxane with hydroxyl value content of 20-70mgKOH/g into polyurethane resin.

3) And (3) after the dropwise addition is finished, keeping the temperature and stirring for 30-60min to obtain the modified polyurethane resin.

The leather prepared by the preparation process of the blending modified soil-release leather comprises a surface layer, a polyurethane transition layer, a high solid content polyurethane layer and a superfine fiber woven fabric layer, wherein the surface layer, the polyurethane transition layer, the high solid content polyurethane layer and the superfine fiber woven fabric layer are sequentially overlapped and compounded together from top to bottom to form a whole, and the surface layer is a modified polyurethane layer.

The invention has the advantages of ingenious process, no need of gravure printing, good compatibility, no separation and good precipitation by adopting the modified polyurethane resin for internal addition. The modified polyurethane resin is a polyurethane coating resin with a certain anti-fouling effect, and the surface of the modified resin has the effects of water resistance, oil repellency, adhesion resistance and doodling prevention. The leather has good antibacterial effect.

Drawings

FIG. 1 is a schematic representation of the leather of the present invention.

Detailed Description

Referring to the attached drawing 1, the leather prepared by the preparation process of the blending modified soil-release leather comprises a surface layer 1, a polyurethane transition layer 2, a high solid content polyurethane layer 3 and a superfine fiber woven fabric layer 4, wherein the surface layer 1, the polyurethane transition layer 2, the high solid content polyurethane layer 3 and the superfine fiber woven fabric layer 4 are sequentially overlapped and compounded together from top to bottom to form a whole, and the surface layer is a modified polyurethane layer.

Example 1

A preparation process of blending modified easy-cleaning leather, which comprises the following steps,

a. coating the modified polyurethane mixed slurry on release paper, and drying for 2 minutes at 80 ℃ to form a surface layer, wherein the coating weight is 100g per square meter; the modified polyurethane mixed slurry comprises the following components in parts by weight: modified polyurethane resin: 100 parts by mass of a leveling agent: 0.3 part by mass, 1.0 part by mass of aliphatic NCO prepolymer, 0.1 part by mass of defoaming agent and 0.8 part by mass of mildew preventive.

The preparation method of the modified polyurethane resin comprises the following steps:

1) firstly, 100 parts by mass of one or two of polyester, polyether or polycarbonate type polyurethane resin with the solid content of 20 percent is heated to 70 ℃, and the viscosity of the system is reduced.

2) Respectively and slowly dropwise adding 3 parts by mass of di-and trifunctional isocyanate curing agents with NCO content of 6% and 0.5 part by mass of hydroxyl polyether modified siloxane with hydroxyl value content of 20mgKOH/g into polyurethane resin.

3) And (3) after the dropwise addition is finished, keeping the temperature and stirring for 30min to obtain the modified polyurethane resin.

b. Coating the polyurethane mixed slurry on release paper, drying for 2 minutes at 90 ℃, wherein the coating weight is 120 g/square meter, and forming a polyurethane transition layer; the polyurethane mixed slurry, wherein: polyurethane resin: 100 parts by mass of color paste: 4 parts by mass of a leveling agent: 0.3 part by mass of an aliphatic NCO prepolymer: 1.5 parts by mass and 0.1 part by mass of a defoaming agent.

c. Coating the environment-friendly high-solid-content polyurethane slurry on the dried polyurethane transition layer, baking for 1 minute at 120 ℃, wherein the coating weight is 180 g/square meter, and forming a high-solid-content polyurethane slurry layer; the environment-friendly high-solid-content polyurethane slurry comprises the following components: high solid content polyurethane: 100 parts by mass, 1.4 parts by mass of amine curing agent, 2 parts by mass of dichloromethane and 5 parts by mass of methyl acetate.

d. And C, overlapping the 0.8mm superfine fiber woven fabric on the high-solid-content polyurethane slurry layer obtained in the step C, and extruding and compounding by using a compression roller, wherein the pressure of the compression roller is 0.2 MPa.

e. Oven-baking at 130 deg.C for 5 min.

f. Cooling to normal temperature through a cooling wheel, and separating the leather from the release paper to obtain the superfine fiber synthetic leather which is high temperature resistant, easy to clean and antibacterial.

Example 2

A preparation process of blending modified easy-cleaning leather, which comprises the following steps,

a. coating the modified polyurethane mixed slurry on release paper, and drying for 3 minutes at 90 ℃ to form a surface layer, wherein the coating weight is 120g per square meter; the modified polyurethane mixed slurry comprises the following components in parts by weight: modified polyurethane resin: 100 parts by mass of a leveling agent: 0.5 part by mass, 2.0 parts by mass of aliphatic NCO prepolymer, 0.2 part by mass of defoaming agent and 1.5 parts by mass of mildew preventive.

The preparation method of the modified polyurethane resin comprises the following steps:

1) firstly, 100 parts by mass of one or two polyurethane resins of polyester, polyether or polycarbonate type with the solid content of 50 percent is heated to 90 ℃, and the viscosity of the system is reduced.

2) 4 parts by mass of a di-functional isocyanate curing agent with NCO content of 9 percent and 3 parts by mass of hydroxyl polyether modified siloxane with hydroxyl value content of 70mgKOH/g are respectively and slowly dripped into polyurethane resin.

3) And (3) after the dropwise addition is finished, keeping the temperature and stirring for 60min to obtain the modified polyurethane resin.

b. Coating the polyurethane mixed slurry on release paper, and drying for 3 minutes at 100 ℃ to form a polyurethane transition layer, wherein the coating weight is 140g per square meter; the polyurethane mixed slurry, wherein: polyurethane resin: 100 parts by mass of color paste: 12 parts by mass of a leveling agent: 0.5 part by mass of an aliphatic NCO prepolymer: 3 parts by mass and 0.2 part by mass of a defoaming agent.

c. Coating the environment-friendly high-solid-content polyurethane slurry on the dried polyurethane transition layer, baking for 1.5 minutes at 130 ℃, wherein the coating weight is 220 g/square meter, and forming a high-solid-content polyurethane slurry layer; the environment-friendly high-solid-content polyurethane slurry comprises the following components: high solid content polyurethane: 100 parts by mass, 1.4 parts by mass of diamine curing agent, 3 parts by mass of dichloromethane and 10 parts by mass of methyl acetate.

d. And C, overlapping the 0.9mm superfine fiber woven fabric on the high-solid-content polyurethane slurry layer obtained in the step C, and extruding and compounding by using a compression roller, wherein the pressure of the compression roller is 0.3 MPa.

e. Baking in an oven at 140 deg.C for 7 min.

f. Cooling to normal temperature through a cooling wheel, and separating the leather from the release paper to obtain the superfine fiber synthetic leather which is high temperature resistant, easy to clean and antibacterial.

Example 3

A preparation process of blending modified easy-cleaning leather, which comprises the following steps,

a. coating the modified polyurethane mixed slurry on release paper, drying for 2.5 minutes at 85 ℃, wherein the coating amount is 110g per square meter, and forming a surface layer; the modified polyurethane mixed slurry comprises the following components in parts by weight: modified polyurethane resin: 100 parts by mass of a leveling agent: 0.4 part by mass, 2 parts by mass of aliphatic NCO prepolymer, 0.15 part by mass of defoaming agent and 1.15 parts by mass of mildew preventive.

The preparation method of the modified polyurethane resin comprises the following steps:

1) firstly, 100 parts by mass of one or two polyurethane resins of polyester, polyether or polycarbonate type with the solid content of 30 percent is heated to 80 ℃, and the viscosity of the system is reduced.

2) Respectively and slowly dripping 3 parts by mass of di-and trifunctional isocyanate curing agents with NCO content of 8% and 2 parts by mass of hydroxyl polyether modified siloxane with hydroxyl value content of 50mgKOH/g into polyurethane resin.

3) And (3) after the dropwise addition is finished, keeping the temperature and stirring for 30-60min to obtain the modified polyurethane resin.

b. Coating the polyurethane mixed slurry on release paper, drying for 2.5 minutes at 95 ℃, wherein the coating weight is 130g per square meter, and forming a polyurethane transition layer; the polyurethane mixed slurry, wherein: polyurethane resin: 100 parts by mass of color paste: 8 parts by mass of a leveling agent: 0.4 part by mass, 2 parts by mass of aliphatic NCO prepolymer and 0.15 part by mass of defoaming agent.

c. Coating the environment-friendly high-solid-content polyurethane slurry on the dried polyurethane transition layer, baking for 1.3 minutes at 125 ℃, wherein the coating weight is 200 g/square meter, and forming a high-solid-content polyurethane slurry layer; the environment-friendly high-solid-content polyurethane slurry comprises the following components: high solid content polyurethane: 100 parts by mass, 1.0 part by mass of diamine curing agent, 2.5 parts by mass of dichloromethane and 8 parts by mass of methyl acetate.

d. And C, overlapping the 0.85mm superfine fiber woven fabric on the high-solid-content polyurethane slurry layer obtained in the step C, and extruding and compounding by using a compression roller, wherein the pressure of the compression roller is 0.25 MPa.

e. Baking in an oven at 140 deg.C for 6 min.

f. Cooling to normal temperature through a cooling wheel, and separating the leather from the release paper to obtain the superfine fiber synthetic leather which is high temperature resistant, easy to clean and antibacterial.

The technical effects of the invention are illustrated as follows:

1. the modified single-end dihydroxy polyether siloxane enables the leather surface to form a hydrophobic and oleophobic protective layer to prevent stains from attaching; the application method of the single-ended dihydroxy polyether siloxane (which is characterized in that the molecular weight is 1000-2500, and the small molecular weight silicone oil can cause easy migration and precipitation in a material interface layer) comprises the steps of slowly dripping the siloxane in a sealed container, simultaneously heating, stirring at a high speed and stirring at a high speed, so that-OH groups in the silicone oil and-NCO groups of the aliphatic NCO prepolymer are slowly reacted to generate the siloxane, and the problem of poor compatibility of polyurethane and the silicone oil after film formation is solved. The aliphatic NCO prepolymer and the polyurethane system can be compatible in any proportion, the compatibility of the silicone oil in the system is general, and the silicone oil can be separated out and separated from the system when the addition amount is large.

2. the-OH and-NCO at the end of the hydroxyl-terminated polyether siloxane molecular chain react at high temperature to generate carbamate, so that the silicone oil is stably dispersed in the polyurethane coating, the precipitation is prevented, and the long-term stain resistance effect is maintained.

3. And (c) reacting the NCO prepolymer in the step B with residual unreacted-OH in the coating in the step a, and enhancing the interlayer adhesion through a chemical reaction.

4. The adhesive layer is made of thermosetting polyurethane, so that the problem of low softening point (160-.

5. The surface layer is added with the composite antibacterial agent, so that the product has broad-spectrum antibacterial effect.

And (3) comparison of detection results:

。

through the comparison, the anti-fouling performance grade of the leather disclosed by the invention is far higher than that of the conventional common leather by at least 2 grades, so that the leather can be applied to some special occasions, and is similar to a kitchen and bathroom space, and a public space is relatively applicable.

The leather antibacterial effect detection of the invention:

1. test strains: escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538

ISO 22196-2011。

And (4) sample treatment, namely, testing the sample, sterilizing the sample by using 70% ethanol, and washing the sample by using sterile water.

The eluent is SCDLP broth.

The contact time is 24 hours.

Test sample 50mmX50mm, inoculum size 0.4 mL.

。

2. Test strains:

candida albicans ATCC 10231.

Klebsiella pneumoniae ATCC 4352.

ISO 22 196-2011。

And (4) sample treatment, namely, testing the sample, sterilizing the sample by using 70% ethanol, and washing the sample by using sterile water.

The eluent is SCDLP broth.

The contact time is 24 hours.

The test sample is 50mmX50mm, and the inoculation amount is 0.4 mL.

。

Antibacterial effect evaluation reference value (refer to JIS Z2801-2012):

when the antibacterial activity value is more than or equal to 2.0, the product has antibacterial effect.

The leather of the invention has antibacterial effect against Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538, Candida albicans ATCC10231 and Klebsiella pneumoniae ATCC 4352.