CN112029933A - High-wear-resistance scratch-resistant top-layer nappa leather and preparation method thereof - Google Patents
High-wear-resistance scratch-resistant top-layer nappa leather and preparation method thereof Download PDFInfo
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- CN112029933A CN112029933A CN202010998612.XA CN202010998612A CN112029933A CN 112029933 A CN112029933 A CN 112029933A CN 202010998612 A CN202010998612 A CN 202010998612A CN 112029933 A CN112029933 A CN 112029933A
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- C—CHEMISTRY; METALLURGY
- C14—SKINS; HIDES; PELTS; LEATHER
- C14C—CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
- C14C13/00—Manufacture of special kinds or leather, e.g. vellum
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- C—CHEMISTRY; METALLURGY
- C14—SKINS; HIDES; PELTS; LEATHER
- C14B—MECHANICAL TREATMENT OR PROCESSING OF SKINS, HIDES OR LEATHER IN GENERAL; PELT-SHEARING MACHINES; INTESTINE-SPLITTING MACHINES
- C14B7/00—Special leathers and their manufacture
- C14B7/02—Composite leathers
- C14B7/04—Composite leathers by cementing or pressing together leather pieces, strips or layers, Reinforcing or stiffening leather by means of reinforcing layers
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- C—CHEMISTRY; METALLURGY
- C14—SKINS; HIDES; PELTS; LEATHER
- C14C—CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
- C14C11/00—Surface finishing of leather
Abstract
The invention discloses a high-wear-resistance scratch-resistant first-layer nappa leather and a preparation method thereof, wherein the first-layer nappa leather is prepared from the following components: 45-50% of first layer cow leather, 40-45% of grain flour skin, 2-3% of adhesive, 5-7% of resin, 1-2% of high-activity softening enzyme and 1-2% of water, and the preparation method comprises the following steps: step S1: preparing first layer cowhide, grain surface skin, adhesive, resin, high activity softening enzyme and water; step S2: preparing a high-activity softening enzyme solution, respectively putting the first layer cowhide and the grain flour skin into the high-activity softening enzyme solution, and heating and preserving heat; step S3: and drying the soaked first layer cowhide and grain flour skin. The first-layer nappa leather designed by the invention reduces the resin dosage and proportion on the basis of no solvent and two layers, and the resin can form a film and keep very good activity by adjusting the linear speed of a production line and controlling the temperature, so that the finished leather has good covering power and extremely high physical properties.
Description
Technical Field
The invention relates to the technical field of leather treatment, in particular to high-wear-resistance scratch-resistant top-layer nappa leather and a preparation method thereof.
Background
The Napapi is a grain leather which belongs to a high-grade material in leather, the surface of the grain leather is provided with a layer of natural wax feeling, the clearer grain surface of the grain leather represents the higher grade, the higher glossiness of the grain leather is, the finer and smoother leather is, and the Napapi is widely applied to the industries of fur, vamps, cases and the like. For example, chinese patent with publication number CN210436732U discloses a natural-grain nappa leather, which comprises a sun-proof layer, a polyurethane layer, a protective layer and a grain surface layer, wherein the upper end surface of the grain surface layer is fixedly connected with the protective layer for resisting tension, the grain surface layer is fixedly connected with the polyurethane layer for preventing tension through the protective layer, the protective layer comprises a tension layer and connecting holes, and the outer end surface of the tension layer is uniformly and equidistantly provided with the connecting holes for ventilation. This design is through setting up sun-proof layer, and sun-proof layer can carry out the sun-proof operation of omnidirectional to grain surface layer upper portion, and then has improved the outside barrier propterty of grain surface layer, prevents to cause the leather to fade owing to sunshine penetrates directly, has improved the protection to the leather outside, and sun-proof in situ portion's multiunit is the fixed arch of curved form simultaneously and arranges in sun-proof layer basement membrane outside, can form the diffuse reflection to prevented that the sunlight from directly shining the grain surface layer outside, improved the protectiveness to grain surface layer.
However, finished leather manufactured by the traditional Napa leather production process and an old-fashioned Napa leather production line which is not modified has hard hand feeling, poor peeling strength, poor wear resistance and poor covering power, and the quality of the Napa leather is seriously influenced, so that a high-wear-resistance scratch-resistant Napa leather and a preparation method thereof are provided for solving the problems.
Disclosure of Invention
Based on the technical problems in the background art, the invention provides a high-wear-resistance scratch-resistant top layer nappa leather and a preparation method thereof.
The invention provides a high-wear-resistance scratch-resistant top layer nappa leather, which is prepared from the following components: 45-50% of first layer cow leather, 40-45% of grain flour skin, 2-3% of adhesive, 5-7% of resin, 1-2% of high-activity softening enzyme and 1-2% of water.
The invention also provides a preparation method of the high-wear-resistance scratch-resistant top-layer nappa leather, which comprises the following steps:
step S1: preparing first layer cowhide, grain surface skin, adhesive, resin, high activity softening enzyme and water;
step S2: preparing a high-activity softening enzyme solution, respectively putting the first layer cowhide and the grain flour skin into the high-activity softening enzyme solution, and heating and insulating the first layer cowhide and the grain flour skin to obtain the soaked first layer cowhide and grain flour skin;
step S3: drying the soaked first layer cowhide and grain flour skin in the step S2, and pressurizing and twisting the first layer cowhide and the grain flour skin in the drying process to obtain softened first layer cowhide and grain flour skin;
step S4: spreading the softened first layer cowhide and the grain leather in the step S3, cleaning the surfaces, heating an adhesive, brushing the adhesive on the surfaces of the first layer cowhide and the grain leather, spreading and drying for a period of time, and then bonding the glue-coated surfaces of the first layer cowhide and the grain leather together to obtain a semi-finished leather product;
step S5: carrying out hot-pressing and laminating on the semi-finished leather product obtained in the step S4 to obtain a leather blank;
step S6: pressing nano parquet on the surface of the leather blank in the step S5;
step S7: and melting the resin, spraying the melted resin on the napa lines on the surface of the leather blank, and naturally air-drying and cooling to obtain a finished product of the top layer napa leather.
Preferably, in step S1, the adhesive is acrylic acid, and the high-activity softening enzyme is softening enzyme JB-II.
Preferably, in step S2, the concentration of the high-activity softening enzyme soaked in the first layer cowhide is 15% to 25%, and the concentration of the high-activity softening enzyme soaked in the grain skin is 20% to 35%.
Preferably, in the step S3, the twisting force of the first layer cowhide is 85 to 105 cows, the twisting force of the grain flour skin is 100 to 125 cows, and the drying temperature is 65 to 75 ℃.
Preferably, the rolling time of the first layer cowhide is 6-8 minutes, the frequency is 8-12 times per minute, the rolling time of the grain flour skin is 8-10 minutes, and the frequency is 10-15 times per minute.
Preferably, in the step S4, the amount of the adhesive is 20 to 25 g per square meter.
Preferably, in the step S5, the pressing pressure of the leather semi-finished product is 10 to 15 mpa, and the pressing temperature is 70 to 75 ℃.
Preferably, in the step S7, the amount of the resin is 35 to 40 grams per square meter.
The high-wear-resistance scratch-resistant top-layer nappa leather and the preparation method thereof have the beneficial effects that:
the preparation method of the first-layer nappa leather disclosed by the invention solves the problems that the finished leather manufactured by the traditional process and an old production line which is not modified has hard hand feeling, poor peeling strength, poor wear resistance and poor covering power;
the first-layer nappa leather designed by the invention reduces the resin dosage and proportion on the basis of no solvent and two layers, and the resin can form a film and keep very good activity by adjusting the linear speed of a production line and controlling the temperature, so that the finished leather has good covering power and extremely high physical properties.
Detailed Description
The present invention will be further illustrated with reference to the following specific examples.
Example one
A high-wear-resistance scratch-resistant first-layer nappa leather is prepared from the following components: 45% of first layer cowhide, 45% of grain flour skin, 2% of adhesive, 5% of resin, 2% of high-activity softening enzyme and 1% of water.
The embodiment also provides a preparation method of the high-wear-resistance scratch-resistant top-layer nappa leather, which comprises the following steps:
step S1: preparing first layer cowhide, grain surface skin, adhesive, resin, high activity softening enzyme and water;
step S2: preparing a high-activity softening enzyme solution, respectively putting the first layer cowhide and the grain flour skin into the high-activity softening enzyme solution, and heating and insulating the first layer cowhide and the grain flour skin to obtain the soaked first layer cowhide and grain flour skin;
step S3: drying the soaked first layer cowhide and grain flour skin in the step S2, and pressurizing and twisting the first layer cowhide and the grain flour skin in the drying process to obtain softened first layer cowhide and grain flour skin;
step S4: spreading the softened first layer cowhide and the grain leather in the step S3, cleaning the surfaces, heating an adhesive, brushing the adhesive on the surfaces of the first layer cowhide and the grain leather, spreading and drying for a period of time, and then bonding the glue-coated surfaces of the first layer cowhide and the grain leather together to obtain a semi-finished leather product;
step S5: carrying out hot-pressing and laminating on the semi-finished leather product obtained in the step S4 to obtain a leather blank;
step S6: pressing nano parquet on the surface of the leather blank in the step S5;
step S7: and melting the resin, spraying the melted resin on the napa lines on the surface of the leather blank, and naturally air-drying and cooling to obtain a finished product of the top layer napa leather.
In this embodiment, in step S1, acrylic acid is used as the adhesive, softening enzyme JB-II is used as the high-activity softening enzyme, in step S2, the concentration of the high-activity softening enzyme soaked in the first layer cow hide is 15%, the concentration of the high-activity softening enzyme soaked in the grain-flour sheet hide is 20%, in step S3, the rolling force of the first layer cow hide is 85 n, the rolling force of the grain-flour sheet hide is 100 n, and the drying temperature is 65 ℃.
In this embodiment, the rolling time of the first layer cowhide is 6 minutes, the frequency is 8 times per minute, the rolling time of the grain flour skin is 8 minutes, the frequency is 10 times per minute, in step S4, the amount of the adhesive is 20 grams per square meter, in step S5, the pressing pressure of the leather semi-finished product is 10 mpa, the pressing temperature is 70 ℃, and in step S7, the amount of the resin is 35 grams per square meter.
Example two
A high-wear-resistance scratch-resistant first-layer nappa leather is prepared from the following components: 50% of first layer cattle, 40% of grain flour skin, 3% of adhesive, 5% of resin, 1% of high-activity softening enzyme and 1% of water.
The embodiment also provides a preparation method of the high-wear-resistance scratch-resistant top-layer nappa leather, which comprises the following steps:
step S1: preparing first layer cowhide, grain surface skin, adhesive, resin, high activity softening enzyme and water;
step S2: preparing a high-activity softening enzyme solution, respectively putting the first layer cowhide and the grain flour skin into the high-activity softening enzyme solution, and heating and insulating the first layer cowhide and the grain flour skin to obtain the soaked first layer cowhide and grain flour skin;
step S3: drying the soaked first layer cowhide and grain flour skin in the step S2, and pressurizing and twisting the first layer cowhide and the grain flour skin in the drying process to obtain softened first layer cowhide and grain flour skin;
step S4: spreading the softened first layer cowhide and the grain leather in the step S3, cleaning the surfaces, heating an adhesive, brushing the adhesive on the surfaces of the first layer cowhide and the grain leather, spreading and drying for a period of time, and then bonding the glue-coated surfaces of the first layer cowhide and the grain leather together to obtain a semi-finished leather product;
step S5: carrying out hot-pressing and laminating on the semi-finished leather product obtained in the step S4 to obtain a leather blank;
step S6: pressing nano parquet on the surface of the leather blank in the step S5;
step S7: and melting the resin, spraying the melted resin on the napa lines on the surface of the leather blank, and naturally air-drying and cooling to obtain a finished product of the top layer napa leather.
In this embodiment, in step S1, the adhesive is acrylic acid, the high-activity softening enzyme is softening enzyme JB-II, in step S2, the concentration of the high-activity softening enzyme soaked in the first layer cow hide is 20%, the concentration of the high-activity softening enzyme soaked in the grain-flour sheet hide is 30%, in step S3, the rolling force of the first layer cow hide is 90 n, the rolling force of the grain-flour sheet hide is 115 n, and the drying temperature is 70 ℃.
In this embodiment, the rolling time of the first layer cowhide is 7 minutes, the frequency is 10 times per minute, the rolling time of the grain leather is 9 minutes, the frequency is 12 times per minute, in step S4, the usage amount of the adhesive is 23 grams per square meter, in step S5, the pressing pressure of the leather semi-finished product is 12 mpa, the pressing temperature is 72 ℃, and in step S7, the usage amount of the resin is 36 grams per square meter.
EXAMPLE III
A high-wear-resistance scratch-resistant first-layer nappa leather is prepared from the following components: 48% of first layer cowhide, 40% of grain surface skin, 3% of adhesive, 7% of resin, 1% of high-activity softening enzyme and 1% of water.
The embodiment also provides a preparation method of the high-wear-resistance scratch-resistant top-layer nappa leather, which comprises the following steps:
step S1: preparing first layer cowhide, grain surface skin, adhesive, resin, high activity softening enzyme and water;
step S2: preparing a high-activity softening enzyme solution, respectively putting the first layer cowhide and the grain flour skin into the high-activity softening enzyme solution, and heating and insulating the first layer cowhide and the grain flour skin to obtain the soaked first layer cowhide and grain flour skin;
step S3: drying the soaked first layer cowhide and grain flour skin in the step S2, and pressurizing and twisting the first layer cowhide and the grain flour skin in the drying process to obtain softened first layer cowhide and grain flour skin;
step S4: spreading the softened first layer cowhide and the grain leather in the step S3, cleaning the surfaces, heating an adhesive, brushing the adhesive on the surfaces of the first layer cowhide and the grain leather, spreading and drying for a period of time, and then bonding the glue-coated surfaces of the first layer cowhide and the grain leather together to obtain a semi-finished leather product;
step S5: carrying out hot-pressing and laminating on the semi-finished leather product obtained in the step S4 to obtain a leather blank;
step S6: pressing nano parquet on the surface of the leather blank in the step S5;
step S7: and melting the resin, spraying the melted resin on the napa lines on the surface of the leather blank, and naturally air-drying and cooling to obtain a finished product of the top layer napa leather.
In this embodiment, in step S1, the adhesive is acrylic acid, the high-activity softening enzyme is softening enzyme JB-II, in step S2, the concentration of the high-activity softening enzyme soaked in the first layer cow hide is 25%, the concentration of the high-activity softening enzyme soaked in the grain-flour sheet hide is 35%, in step S3, the rolling force of the first layer cow hide is 105 n, the rolling force of the grain-flour sheet hide is 125 n, and the drying temperature is 75 ℃.
In this embodiment, the rolling time of the first layer cowhide is 8 minutes, the frequency is 12 times per minute, the rolling time of the grain leather is 10 minutes, the frequency is 15 times per minute, in step S4, the amount of the adhesive is 25 grams per square meter, in step S5, the pressing pressure of the leather semi-finished product is 15 mpa, the pressing temperature is 75 ℃, and in step S7, the amount of the resin is 40 grams per square meter.
The properties of the top nappa leather produced by the above examples were studied:
the result shows that the first-layer nappa leather prepared by the method has good waterproof and scratch-resistant effects, tensile resistance and long service life, and the third embodiment is the best embodiment.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (9)
1. The high-wear-resistance scratch-resistant first-layer nappa leather is characterized by being prepared from the following components in parts by weight: 45-50% of first layer cow leather, 40-45% of grain flour skin, 2-3% of adhesive, 5-7% of resin, 1-2% of high-activity softening enzyme and 1-2% of water.
2. A preparation method of high-wear-resistance scratch-resistant top-layer nappa leather is characterized by comprising the following steps:
step S1: preparing first layer cowhide, grain surface skin, adhesive, resin, high activity softening enzyme and water;
step S2: preparing a high-activity softening enzyme solution, respectively putting the first layer cowhide and the grain flour skin into the high-activity softening enzyme solution, and heating and insulating the first layer cowhide and the grain flour skin to obtain the soaked first layer cowhide and grain flour skin;
step S3: drying the soaked first layer cowhide and grain flour skin in the step S2, and pressurizing and twisting the first layer cowhide and the grain flour skin in the drying process to obtain softened first layer cowhide and grain flour skin;
step S4: spreading the softened first layer cowhide and the grain leather in the step S3, cleaning the surfaces, heating an adhesive, brushing the adhesive on the surfaces of the first layer cowhide and the grain leather, spreading and drying for a period of time, and then bonding the glue-coated surfaces of the first layer cowhide and the grain leather together to obtain a semi-finished leather product;
step S5: carrying out hot-pressing and laminating on the semi-finished leather product obtained in the step S4 to obtain a leather blank;
step S6: pressing nano parquet on the surface of the leather blank in the step S5;
step S7: and melting the resin, spraying the melted resin on the napa lines on the surface of the leather blank, and naturally air-drying and cooling to obtain a finished product of the top layer napa leather.
3. The method for preparing napa leather with high wear resistance and scratch resistance according to claim 2, wherein in step S1, the adhesive is acrylic acid, and the high-activity softening enzyme is softening enzyme JB-II.
4. The method for preparing high-wear-resistance scratch-resistant top-layer nappa leather according to claim 2, wherein in step S2, the concentration of the high-activity softening enzyme soaked by the top-layer cowhide is 15% -25%, and the concentration of the high-activity softening enzyme soaked by the grain leather is 20% -35%.
5. The method for preparing high-wear-resistance scratch-resistant top-layer nappa leather according to claim 2, wherein in step S3, the twisting force of the top-layer cowhide is 85-105 n, the twisting force of the grain-flour skin is 100-125 n, and the drying temperature is 65-75 ℃.
6. The preparation method of the high-wear-resistance scratch-resistant top napa leather according to claim 5, wherein the rolling time of the top cowhide is 6-8 minutes, the frequency is 8-12 times per minute, the rolling time of the grain wrapper is 8-10 minutes, and the frequency is 10-15 times per minute.
7. The method for preparing high-abrasion-resistance scratch-resistant top-layer nappa leather as claimed in claim 2, wherein in step S4, the amount of the adhesive is 20-25 g/m.
8. The method for preparing high-wear-resistance scratch-resistant leather with the first napping layer as claimed in claim 2, wherein in step S5, the semi-finished leather product has a pressing pressure of 10-15 mpa and a pressing temperature of 70-75 ℃.
9. The method for preparing high-abrasion-resistance scratch-resistant top-layer nappa leather as claimed in claim 2, wherein in step S7, the amount of the resin is 35-40 g/m.
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| CN202010998612.XA CN112029933A (en) | 2020-09-22 | 2020-09-22 | High-wear-resistance scratch-resistant top-layer nappa leather and preparation method thereof |
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| CN202010998612.XA CN112029933A (en) | 2020-09-22 | 2020-09-22 | High-wear-resistance scratch-resistant top-layer nappa leather and preparation method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115678350A (en) * | 2022-11-28 | 2023-02-03 | 瑞安市吉尔康鞋业有限公司 | Wear-resistant leather shoes and processing technology thereof |
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| CN115678350A (en) * | 2022-11-28 | 2023-02-03 | 瑞安市吉尔康鞋业有限公司 | Wear-resistant leather shoes and processing technology thereof |
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