Environment-friendly odorless cow leather treatment process

Abstract

The invention provides an environment-friendly odorless cow leather treatment process, which belongs to the technical field of cow leather processing, and comprises the following steps: S1, softening cow leather by vibration, patching, buffing the leather, trimming the buffed cow leather, removing parts which cannot be used, and ironing the trimmed cow leather; s2, the ironed cow leather is coated with the coating A in a roller coating mode, and a coating A is obtained; nitrocotton paint is used on the coating A to increase the water resistance, then embossing, milling and toggling are sequentially carried out, and paint B is used for inner sealing operation; the coating A comprises the following components: water, wax, resin, pigment paste and a hand feeling agent; the coating B comprises the following components: water, resin and nonionic oil; s3, the surface of the cowhide finally obtained in the step S2 is sequentially coated with a batter adhesion agent, batter and gloss oil, then the cowhide is subjected to standing and drying, finally, ironing is conducted, and the finished cowhide is obtained. According to the environment-friendly odorless cow leather treatment process, heavy metal wastewater is not generated, and odorless leather is obtained.

Description

Technical Field

[0001] The invention relates to the technical field of cowhide processing, and in particular to an environmentally friendly and odorless cowhide processing process. Background Art

[0002] Leather is a denatured, non-perishable animal skin obtained through physical and chemical processes such as depilation and tanning. It can be made into leather shoes, bags, clothes, sofas and other leather products, and has a wide range of applications. Cowhide, sheepskin and pigskin are the three main types of leather used for leather production. Cowhide has the characteristics of thick texture, high strength and strong durability, and is a high-quality choice for high-end leather goods, shoes and furniture.

[0003] By processing raw cowhide, it is transformed into durable and beautiful leather. The processing methods of cowhide mainly include depilation, degreasing, tanning and other steps. Among them, tanning is the core link, and commonly used methods include chrome tanning (accounting for more than 80%) and vegetable tanning. Chrome tanning uses chemicals such as chromium sulfate to give leather softness and heat resistance, but it will produce chromium-containing wastewater, there is a risk of heavy metal pollution, and the auxiliaries used are easy to remain in the leather, resulting in a bad smell of the finished product. Although the vegetable tanning method is environmentally friendly, it takes a long time and the finished product is hard, has poor air permeability, and is limited in applicability. Even the leather that has been vegetable tanned will have a certain smell on the leather surface. Summary of the invention

[0004] In view of this, the present invention provides an environmentally friendly and odorless cowhide processing process, which does not generate heavy metal wastewater and obtains odorless leather.

[0005] To achieve the above object, the present invention provides an environmentally friendly and odorless cowhide treatment process, comprising the following steps: S1. After the leather is softened, it is repaired and then polished. The leather obtained after polishing is trimmed to remove the unusable part, and the trimmed leather is ironed; S2. Coating A is applied to the ironed cowhide with a roller to obtain coating A; nitrocellulose coating is used on coating A to increase water resistance, and then embossing, softening, and stretching are performed in sequence, and coating B is used for sealing; the coating A comprises the following components: water, wax, resin, pigment paste, and hand feeling agent; the coating B comprises the following components: water, resin and non-ionic oil; S3. The surface of the cowhide obtained at the end of step S2 is coated with a paste adhesive, a paste, and a varnish in sequence, and then the cowhide is left to stand, dried, and finally ironed to obtain a finished cowhide.

[0006] Optionally, the coating A includes the following components in parts by weight: 6-10 parts of water, 10-20 parts of wax, 130-150 parts of resin, 8-12 parts of pigment paste, and 0.1-0.2 parts of feel agent; the resin includes the following components in parts by weight: 65-75 parts of composite resin, 30-35 parts of acrylic resin, and 35-40 parts of polyurethane.

[0007] Optionally, the wax is one or a combination of water-soluble wax and anti-stick wax. Optionally, the coating A includes the following components in parts by weight: 8 parts of water, 5 parts of wax DC-111, 10 parts of anti-sticking wax AW551, 70 parts of composite resin 1519, 32 parts of acrylic resin 1018, 15 parts of polyurethane 1316T, 25 parts of polyurethane 52, 10 parts of pigment paste, and 0.1 parts of feel agent 2229-JXH.

[0008] Optionally, the ingredients of the nitrocellulose coating are water and water-based nitrocellulose, and the mass ratio of water to water-based nitrocellulose is 1:1; the coating B includes the following components in parts by weight: 40-42 parts of water, 2-5 parts of resin, and 0.2-0.8 parts of non-ionic oil.

[0009] Optionally, the aqueous nitrocellulose is aqueous nitrocellulose 7560.

[0010] Optionally, the resin is a composite resin.

[0011] Optionally, the wound is healed using a healing ointment, and the healing ointment is healing ointment 1050 or healing ointment 556.

[0012] Optionally, the coating B includes the following components in parts by weight: 41 parts of water, 3.5 parts of composite resin 1520, and 0.5 parts of non-ionic oil KT23.

[0013] Optionally, the batter adhesive includes the following components in parts by weight: 5-9 parts of water, 38-42 parts of composite resin, 28-32 parts of acrylic resin, 38-42 parts of polyurethane resin, 2-4 parts of wax, 8-12 parts of pigment paste, and 0.08-0.12 parts of hand feeling agent.

[0014] Optionally, the batter adhesive includes the following components in parts by weight: 7 parts of water, 40 parts of composite resin 1519, 30 parts of acrylic resin 1016, 40 parts of polyurethane resin 2021, 3 parts of wax DC-111, 10 parts of pigment paste, and 0.1 parts of hand feeling agent 2229-JXH.

[0015] Optionally, the batter comprises the following components in parts by weight: 8-12 parts of water, 13-17 parts of wax, 32-37 parts of composite resin, 28-32 parts of acrylic resin, 28-32 parts of polyurethane resin, 8-12 parts of pigment paste, and 0.08-0.15 parts of a hand feeling agent.

[0016] Optionally, the batter includes the following components in parts by weight: 10 parts of water, 10 parts of wax DC-111, 5 parts of anti-stick wax AW551, 35 parts of composite resin 1733, 30 parts of acrylic resin 1016, 15 parts of polyurethane 3096, 15 parts of polyurethane 1316T, 10 parts of pigment paste, and 0.1 parts of hand feeling agent 2229-JXH.

[0017] Optionally, the varnish comprises the following components in parts by weight: 95-105 parts of water, 95-105 parts of water-based top-glazing polyurethane, 3-5 parts of a cross-linking agent, and 4-5 parts of a hand-feeling agent.

[0018] Optionally, the varnish includes the following components in parts by weight: 100 parts of water, 100 parts of water-based top-glazing polyurethane, 4 parts of cross-linking agent JD100, 1.5 parts of feeling agent 2229-JXH, and 3 parts of feeling agent 780.

[0019] Optionally, the leather grinding after the wound repair in step S1 includes sequentially performing a first wound repair, leather grinding, a second wound repair, and leather grinding.

[0020] Optionally, the coating parameter of the coating A is 6.8~7.0g / SF; the coating parameter of the nitrocellulose coating is 1.8~2.2g / SF; the coating parameter of the coating B is 1.4~1.6g / SF; the coating parameter of the batter adhesive is 2.4~2.6g / SF; the coating parameter of the batter is 1.8~2.2g / SF; and the coating parameter of the varnish is 1.8~2.2g / SF.

[0021] Optionally, the batter is applied repeatedly 2 to 4 times, and the varnish is applied repeatedly 2 to 3 times.

[0022] The above technical solution of the present invention includes at least the following beneficial effects: In the technical solution provided by the present invention, harmful substances such as chromium salts and formaldehyde are completely discarded, and traditional solvent-based chemicals are replaced by water-based coatings (such as nitrocellulose coatings, water-based polyurethane varnishes) and non-ionic oils to eliminate heavy metal pollution and VOCs (such as benzene and formaldehyde) release from the source. By optimizing the coating formula (such as compounding anti-stick wax with water-based resin) and the static drying process, the finished cowhide has no irritating chemical odor, achieving an environmentally friendly process and an odorless finished product. DETAILED DESCRIPTION In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in combination with the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0023] Example 1 An environmentally friendly and odorless cowhide processing process comprises the following steps: After the leather is softened by mechanical vibration, the surface of the leather is coated with a repairing cream 1050, and then the leather is buffed with a particle size of 240#, and then coated with a repairing cream 556, and the particle size of the leather is buffed with a particle size of 400#. By repairing and buffing, the surface damage of the leather is effectively covered and polished, making the surface of the leather smoother and more uniform, laying a good foundation for subsequent processing and improving the grade of the leather.

[0024] After grinding, the leather is trimmed to remove the unusable parts to ensure the size and integrity of the leather. At this time, the size and quantity of leather required can be calculated according to the order demand.

[0025] The trimmed cowhide is ironed at 100°C, 50kg pressure and a speed of 9 meters per minute.

[0026] Coating A was rolled onto the ironed cowhide at a roller coating parameter of 7.0 g / SF, and dried at 65°C for 3 minutes to obtain coating A. Coating A made the cowhide surface smooth and flat, and was closely combined with the cowhide substrate, effectively preventing the coating from falling off and cracking, while improving the wear resistance and crease resistance of the cowhide. Coating A included the following components in parts by weight: 8 parts of water, 5 parts of wax DC-111, 10 parts of anti-sticking wax AW551, 70 parts of composite resin 1519, 32 parts of acrylic resin 1018, 15 parts of polyurethane 1316T, 25 parts of polyurethane 52, 10 parts of pigment paste, and 0.1 parts of hand feeling agent 2229-JXH.

[0027] Applying nitrocellulose coating on coating A increases the water resistance of the coating, improves the physical properties of the coating, and makes it stronger and more durable. The nitrocellulose coating has medium hardness after film formation, feels full and silky, and has good board release properties, which helps as an isolation layer in the next step of high-temperature embossing without affecting the internal coating. The components of nitrocellulose coating are water and water-based nitrocellulose, and the mass ratio of water to water-based nitrocellulose is 1:1.

[0028] Emboss for 3 seconds at 110℃ and 110kg pressure to get the desired pattern. Tumble the embossed leather for 16-18 hours to improve the softness of the leather and give it a tumbled pattern to enhance its texture.

[0029] The softened cowhide is stretched to make the leather surface smoother and easier to operate later.

[0030] The cowhide after stretching is sealed with coating B, which includes the following components by weight: 41 parts of water, 3.5 parts of composite resin 1520, and 0.5 parts of non-ionic oil KT23. The coating parameters of coating B are 1.5g / SF, and it is naturally dried.

[0031] The dried cowhide is coated with a dough adhesive, a dough and a varnish in sequence. The coating parameter of the dough adhesive is 2.5 g / SF, and the cowhide is dried at 65°C for 2 min after coating; the coating parameter of the dough is 2.0 g / SF, and the cowhide is dried at 70°C for 3 min after coating; the coating parameter of the varnish is 2.0 g / SF, and the cowhide is dried at 80°C for 5 min after coating; then the cowhide is left to stand for 12 h, dried at 120°C for 0.5 h, and then ironed at 85°C, 5 kg pressure, and a speed of 9 meters per minute to obtain a finished cowhide; the dough adhesive comprises the following components in parts by weight: 7 parts of water, 40 parts of composite resin 1519, 30 parts of acrylic resin 1016, 40 parts of polymer Urethane resin 2021, 3 parts of wax DC-111, 10 parts of pigment paste, 0.1 parts of feeling agent 2229-JXH; the paste includes the following components in parts by weight: 10 parts of water, 10 parts of wax DC-111, 5 parts of anti-stick wax AW551, 35 parts of composite resin 1733, 30 parts of acrylic resin 1016, 15 parts of polyurethane 3096, 15 parts of polyurethane 1316T, 10 parts of pigment paste, 0.1 parts of feeling agent 2229-JXH; the varnish includes the following components in parts by weight: 100 parts of water, 100 parts of water-based top-light polyurethane, 4 parts of cross-linking agent JD100, 1.5 parts of feeling agent 2229-JXH, 3 parts of feeling agent 780.

[0032] Example 2 Compared with Example 1, the only difference is that coating A includes the following components in parts by weight: 6 parts of water, 8 parts of wax DC-111, 12 parts of anti-stick wax AW551, 75 parts of composite resin 1519, 30 parts of acrylic resin 1018, 25 parts of polyurethane 1316T, 10 parts of polyurethane 52, 12 parts of pigment paste, and 0.2 parts of hand feeling agent 2229-JXH; Coating B includes the following components in parts by weight: 42 parts of water, 5 parts of composite resin 1520, and 0.8 parts of non-ionic oil KT23; The batter adhesive includes the following components in parts by weight: 5 parts of water, 42 parts of composite resin 1519, 28 parts of acrylic resin 1016, 42 parts of polyurethane resin 2021, 4 parts of wax DC-111, 8 parts of pigment paste, and 0.08 parts of hand feeling agent 2229-JXH.

[0033] The dough includes the following components in parts by weight: 12 parts of water, 13 parts of wax DC-111, 4 parts of anti-stick wax AW551, 37 parts of composite resin 1733, 28 parts of acrylic resin 1016, 15 parts of polyurethane 3096, 13 parts of polyurethane 1316T, 12 parts of pigment paste, and 0.15 parts of hand feeling agent 2229-JXH; The varnish includes the following components in parts by weight: 95 parts of water, 105 parts of water-based top-light polyurethane, 3 parts of cross-linking agent JD100, 2 parts of feel agent 2229-JXH, and 2 parts of feel agent 780.

[0034] Example 3 Compared with Example 1, the only difference is that coating A includes the following components in parts by weight: 10 parts of water, 2 parts of wax DC-111, 8 parts of anti-stick wax AW551, 65 parts of composite resin 1519, 30 parts of acrylic resin 1018, 10 parts of polyurethane 1316T, 25 parts of polyurethane 52, 12 parts of pigment paste, and 0.2 parts of hand feeling agent 2229-JXH; Coating B includes the following components in parts by weight: 40 parts of water, 2 parts of composite resin 1520, and 0.2 parts of non-ionic oil KT23; The batter adhesive includes the following components in parts by weight: 9 parts of water, 38 parts of composite resin 1519, 32 parts of acrylic resin 1016, 38 parts of polyurethane resin 2021, 2 parts of wax DC-111, 12 parts of pigment paste, and 0.12 parts of hand feeling agent 2229-JXH.

[0035] The dough includes the following components in parts by weight: 8 parts of water, 10 parts of wax DC-111, 3 parts of anti-stick wax AW551, 32 parts of composite resin 1733, 31 parts of acrylic resin 1016, 20 parts of polyurethane 3096, 12 parts of polyurethane 1316T, 8 parts of pigment paste, and 0.08 parts of hand feeling agent 2229-JXH; The varnish includes the following components in parts by weight: 105 parts of water, 95 parts of water-based top-light polyurethane, 5 parts of cross-linking agent JD100, 3 parts of feel agent 2229-JXH, and 2 parts of feel agent 780.

[0036] Example 4 Compared with Example 1, the only difference is that the coating parameter of coating A is 6.8g / SF; the coating parameter of nitrocellulose coating is 1.8g / SF; the coating parameter of coating B is 1.6g / SF; the coating parameter of batter adhesive is 2.4g / SF; the coating parameter of batter is 2.2g / SF; and the coating parameter of varnish is 1.8g / SF.

[0037] Example 5 Compared with Example 1, the only difference is that the coating parameter of coating A is 7.0g / SF; the coating parameter of nitrocellulose coating is 2.2g / SF; the coating parameter of coating B is 1.4g / SF; the coating parameter of batter adhesive is 2.6g / SF; the coating parameter of batter is 1.8g / SF; and the coating parameter of varnish is 2.2g / SF.

[0038] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An environmentally friendly and odorless cowhide processing process, characterized in that: The following steps are involved: S1. After the leather is softened, it is repaired and then polished. The leather obtained after polishing is trimmed to remove the unusable part, and the trimmed leather is ironed; S2. Coating A is applied to the ironed cowhide by a roller to obtain coating A; Nitrocellulose coating is used on coating A to increase water resistance, and then embossing, softening, and stretching are performed in sequence, and coating B is used for sealing; the coating A includes the following components: water, wax, resin, pigment paste, and hand feeling agent; the coating B includes the following components: water, resin and non-ionic oil; S3. The surface of the cowhide obtained at the end of step S2 is coated with a paste adhesive, a paste, and a varnish in sequence, and then the cowhide is left to stand, dried, and finally ironed to obtain a finished cowhide.

2. The environmentally friendly and odorless cowhide treatment process according to claim 1 is characterized in that: The coating A comprises the following components in parts by weight: 6-10 parts of water, 10-20 parts of wax, 130-150 parts of resin, 8-12 parts of pigment paste, and 0.1-0.2 parts of feel agent; the resin comprises the following components in parts by weight: 65-75 parts of composite resin, 30-35 parts of acrylic resin, and 35-40 parts of polyurethane.

3. The environmentally friendly and odorless cowhide treatment process according to claim 2 is characterized in that: The wax is one or a combination of water-soluble wax and anti-sticking wax.

4. The environmentally friendly and odorless cowhide treatment process according to claim 1 is characterized in that: The components of the nitrocellulose coating are water and water-based nitrocellulose, and the mass ratio of water to water-based nitrocellulose is 1:1; the coating B includes the following components in parts by weight: 40-42 parts of water, 2-5 parts of resin, and 0.2-0.8 parts of non-ionic oil.

5. The environmentally friendly and odorless cowhide treatment process according to claim 4 is characterized in that: The resin is a composite resin.

6. The environmentally friendly and odorless cowhide treatment process according to claim 1 is characterized in that: The batter adhesive comprises the following components in parts by weight: 5-9 parts of water, 38-42 parts of composite resin, 28-32 parts of acrylic resin, 38-42 parts of polyurethane resin, 2-4 parts of wax, 8-12 parts of pigment paste, and 0.08-0.12 parts of hand feeling agent.

7. The environmentally friendly and odorless cowhide treatment process according to claim 1, characterized in that: The dough comprises the following components in parts by weight: 8-12 parts of water, 13-17 parts of wax, 32-37 parts of composite resin, 28-32 parts of acrylic resin, 28-32 parts of polyurethane resin, 8-12 parts of pigment paste, and 0.08-0.15 parts of a hand feeling agent.

8. The environmentally friendly and odorless cowhide treatment process according to claim 1, characterized in that: The varnish comprises the following components in parts by weight: 95-105 parts of water, 95-105 parts of water-based top-varnish polyurethane, 3-5 parts of a cross-linking agent, and 4-5 parts of a hand-feeling agent.

9. The environmentally friendly and odorless cowhide treatment process according to claim 1, characterized in that: In the step S1, the leather grinding after the wound repair includes sequentially performing the first wound repair, leather grinding, the second wound repair, and leather grinding.

10. The environmentally friendly and odorless cowhide treatment process according to claim 1, characterized in that: The coating parameter of the coating A is 6.8~7.0g / SF; the coating parameter of the nitrocellulose coating is 1.8~2.2g / SF; the coating parameter of the coating B is 1.4~1.6g / SF; the coating parameter of the batter adhesive is 2.4~2.6g / SF; the coating parameter of the batter is 1.8~2.2g / SF; the coating parameter of the varnish is 1.8~2.2g / SF.