Preparation method of instep leather based on Dutch cow skin

Abstract

The invention relates to a preparation method of instep leather based on Dutch cow skin. Comprising the following steps of soaking, pre-soaking, fleshing and trimming, main soaking, fleshing and trimming, enzyme unhairing, liming, splitting and trimming, deliming, softening, pickling, less chrome tanning, wringing and shaving, rewetting, primary neutralization, primary filling, chrome-free retanning, secondary neutralization, secondary filling, fat liquoring, color fixing, drying and finishing and finishing. According to the invention, an ecological leather making process technology based on the Holland small cow skin is adopted, so that the original characteristics of finer grain surface texture and pores are ensured, and the defects of relatively loose fiber tissue, thicker subcutaneous tissue layer, poorer physical and mechanical properties and the like are overcome; the instep leather prepared on the basis of the Dutch cow skin has excellent sensory performance, mechanical performance and ecological performance, and the value and market competitiveness of the product are improved.

Description

Technical Field

[0001] The invention relates to the technical field of leather manufacturing, in particular to a method for preparing shoe upper leather based on Dutch calf hide. Background Art

[0002] The Netherlands is a world-renowned dairy producer with a large dairy farming industry and produces high-quality milk. When cows reach a certain age or are no longer suitable for producing milk, they are sent to slaughterhouses for meat to be eaten. The waste produced in this process, cow hides, will be landfilled or incinerated if not properly handled, which will not only waste resources and cause environmental pollution, but also emit a large amount of carbon dioxide.

[0003] Using cowhide as the raw material for leather making is one of the resource processing methods to turn waste into treasure. Compared with conventional cowhide, cowhide has fewer defects and fine grain pores, but it is smaller in width and lower in strength, and it is impossible to directly use traditional leather making technology to produce qualified leather products. Therefore, it is necessary to conduct targeted leather making process technology research, and at the same time develop and integrate ecological process technology to prepare high-end and ecological Dutch cowhide shoe upper leather. In view of this, this case came into being. Summary of the invention

[0004] The invention provides a method for preparing shoe upper leather based on Dutch calf leather, so as to overcome the problems of resource waste, environmental pollution and the like of existing calf leather.

[0005] The present invention adopts the following technical solution:

[0006] A method for preparing shoe upper leather based on Dutch cowhide, comprising the following steps: soaking → pre-soaking → fleshing, trimming → main soaking → fleshing, trimming → enzyme dehairing → liming → splitting, trimming → deliming → softening → pickling → less chrome tanning → squeezing, shaving → rewetting → primary neutralization → primary filling → chrome-free retanning → secondary neutralization → secondary filling → fatliquoring → color fixation → drying, finishing → painting; calculated by weight of Dutch cowhide raw materials, wherein:

[0007] Pre-soaking: put the soaked Dutch calf leather into a drum, add 200% water at 18-21℃, add 0.3% penetrant ProSpread, 0.1% degreaser ProDegreaze, 0.3% soda ash, rotate for 10 minutes, stop for 30 minutes; rotate at 2-3rpm; control the temperature at 19-25℃, pH 6.3-6.7, Baume degree 8-9; repeat 4-6 times; wash with water, and remove from the drum;

[0008] Main soaking: put the pre-soaked, fleshed and trimmed Dutch calf hide into a drum, add 200% water at 18-21℃, and rotate the drum at 3rpm; add 0.1% penetrant ProSpread, 0.3% soaking agent ProSoak, 0.3% degreasing agent ProDegreaze, rotate for 10min, stop for 20min; control pH at 6.3-6.7, rotate at 2-3rpm, repeat 1-3 times; add 0.2-0.4% soda ash, adjust pH to 9.5-10.5, rotate for 10min, stop for 20min; repeat 5-8 times, requiring full penetration and milky white cut; wash with water and remove from drum;

[0009] Enzyme dehairing: put the Dutch calf hide after main soaking, fleshing and trimming into the drum, add 100% of 24-28℃, the drum speed is 6-8rpm, and the pH is adjusted to 9.0-9.5; add penetrant ProSpread 0.3%, compound enzyme A 0.6-0.8%, and rotate for 30 minutes; add keratinase K 0.2-0.4%, and rotate for 30 minutes; check the dehairing situation, if the dehairing rate is greater than 90%, enter the next process; otherwise, continue to rotate for 30-60 minutes; wash with water, filter the hair, and drain the liquid;

[0010] Deliming: Put the split Dutch calf hide into a drum, add 200-250% water at 30-32℃, add 0.3% penetrant ProSpread, add 0.7-1.0% ammonium-free deliming agent DLA, rotate for 15-30min, speed 6rpm; then add 0.7-1.0% ammonium-free deliming agent DLA, rotate for 15-30min; adjust pH to 8.0-8.5;

[0011] Softening: Continue to add ammonium-free softening enzyme CBK 0.2-0.5%, degreasing agent ProDegreaze 0.3%, rotate for 10 minutes, stop for 20 minutes; adjust the temperature to 30-32℃, pH 7.5-8.5, rotate for 10 minutes, stop for 20 minutes; repeat 2-3 times, take the buttocks incision and see that it is colorless to phenolphthalein reagent, which means that the softening is complete; wash with water and remove from the drum;

[0012] Finishing: The finishing process is primer → ironing 1 → top coating → ironing 2 → softening → top coating → ironing 3 → softening → finished product.

[0013] Further, the above soaking: put the Dutch calf hide into a drum, add 300% water at 18-21° C. and 0.3% penetrant ProSpread, rotate for 5 minutes, and stop for 55 minutes; rotate at 1-2 rpm; repeat 1-2 times; and drain.

[0014] Further, the above liming: put Dutch calf hide with a depilation rate of more than 90% into a drum, add 100% of 24-26°C water, and rotate the drum at a speed of 3-5rpm; add 0.3% of penetrant ProSpread and 2% of lime, and rotate for 60 minutes; add 150% of 24-26°C water and 0.15-0.2% of 30% sodium hydroxide solution, and rotate for 60 minutes; then rotate for 5 minutes, stop for 55 minutes, and repeat 5-8 times; wash with water and remove from the drum.

[0015] Furthermore, the above pickling: put the softened Dutch calf hide into a drum, add 100-200% water at 23-25°C, add 7-10% sodium chloride, rotate for 10 minutes, and rotate at 8rpm; adjust the Baume degree ≥ 7; add 0.5-1.5% formic acid with a concentration of 85% diluted with 8-10 times normal temperature water during rotation, and rotate for 30 minutes; add 0.2-0.8% concentrated sulfuric acid with a concentration of 98% diluted with 8-10 times normal temperature water, adjust the pH to 2.5-3.0, and rotate for 60-180 minutes.

[0016] Further, the above-mentioned less-chrome tanning: add cationic oil XGS1%, rotate for 40 minutes, and rotate at a speed of 8rpm; then add chrome powder 0.5-2.5%, rotate for 60 minutes; add zeolite tanning agent BS 5-10%, rotate for 60 minutes; add sodium formate 1.0-2.0%, rotate for 60 minutes; then add baking soda in batches, and slowly adjust the pH to 3.2-3.4; add water 100-150%, continue to add baking soda in batches, slowly adjust the pH to 3.8-4.2, and then rotate for 120-180 minutes; drain the liquid and remove the drum; let it stand for 3-7 days.

[0017] Furthermore, the one-time filling: add 3-5% of small molecule acrylic acid R35, and rotate for 30-90 minutes; add 4-6% of medium molecule acrylic acid B4, and rotate for 30-90 minutes; add 2-4% of macromolecular acrylic acid 007L, and rotate for 30-90 minutes; add 0.5-1% of dispersant T-M, and rotate for 10-30 minutes; add 2-3% of betel nut tannin TDT and 2-3% of synthetic tanning agent JHL, and rotate for 30-90 minutes.

[0018] Further, the above-mentioned chrome-free retanning: add 150% ice water, add 1-3% formic acid, adjust pH2.8-3.5, rotate for 10-30 minutes; add tear-resistant oil F04 0.5-1%, zeolite tanning agent BS 3-8%, rotate for 60 minutes; add sodium formate 1-2%, rotate for 10-30 minutes; add baking soda 0.5-1.0%, adjust pH3.8-4.2, rotate for 10 minutes, stop for 50 minutes; repeat 3-5 times; drain.

[0019] Further, the above secondary filling: add 3-5% of small molecule acrylic acid R35, and rotate for 30-90 minutes; add 4-6% of medium molecule acrylic acid B4, and rotate for 30-90 minutes; add 2-4% of macromolecular acrylic acid 007L, and rotate for 30-90 minutes; add 2-3% of dicyandiamide BLE, 2-3% of synthetic tanning agent JHL, and 2-3% of phenolic synthetic tanning agent MLB, and rotate for 30-90 minutes; add 1-2% of dispersant TM, 2-3% of retanning agent PN, and 3-5% of betel nut tannin GMB, and rotate for 10-30 minutes; add 1-2% of leveling agent LU and 3-5% of dye RHS, and rotate for 60 minutes; make up 150% of 50°C water, add 1.0-2.0% of formic acid in batches, adjust the pH to 3.8-4.2, and rotate for 10-30 minutes; drain.

[0020] Furthermore, the top coating formula is: 300-500 parts of water, 50-100 parts of water-based penetrant PT-4235, 100-200 parts of medium-soft comprehensive resin RC-22-452, 100-200 parts of high-property acrylic resin A-946, 100-200 parts of high-property polyurethane resin RU-73-901, 100-200 parts of non-ionic polyurethane resin RU-77-19750-100 parts, matting agent WD-77-401 100-200 parts, pigment paste 100-200 parts, and release wax FI-5050-100 parts; the coating amount is about 5-10g.

[0021] Furthermore, the top coating formula is: 300-500 parts of water, 300-500 parts of high gloss polyurethane resin WT-42-518, 200-300 parts of matte polyurethane resin WT-13-097, 10-50 parts of crosslinking agent XR-13-906, and 10-50 parts of hand feeling agent WF-5230; the coating amount is about 2-5g.

[0022] It can be seen from the above description of the present invention that, compared with the prior art, the present invention has the following advantages:

[0023] 1. The present application adopts an ecological leather making process technology based on Dutch calf leather, which not only ensures its original characteristics of finer grain texture and pores, but also improves its disadvantages such as relatively loose fiber tissue, thicker subcutaneous tissue layer, and poor physical and mechanical properties. Probiotics are introduced in the pre-tanning preparation stage, and no bactericides are used; enzyme dehairing is adopted, and sulfides are not used; ammonium substances are not used for deliming and softening, so as to improve the safety performance of calf leather; tanning adopts low-chrome tanning technology based on zeolite tanning agent; wet dyeing and finishing focuses on filling performance to make it firm and improve its physical and mechanical properties; the finishing is light and thin, which does not affect the grain appearance and makes the product have good sensory performance; the above-mentioned process technology is adopted to make the upper leather made from Dutch calf leather have excellent sensory performance, mechanical performance and ecological performance, thereby improving the value and market competitiveness of the product.

[0024] 2. Appearance and texture: Calfskin has small pores, evenly and closely distributed, fine grain, plump and shiny leather surface, natural texture and color, high-end and luxurious appearance, which can enhance the texture and value of the product.

[0025] 3. Soft and comfortable: The leather is soft and smooth, feels good, and has good elasticity. It feels as soft and smooth as a quilt when held in the hand. The leather goods, clothing, shoes, etc. made from it are extremely comfortable to wear or use.

[0026] 4. Strong durability: strong tensile strength, good toughness, tight fiber structure, high strength, excellent wear resistance, can withstand daily wear and use, not easy to tear, break or deform, and long service life.

[0027] 5. Good breathability: It has good breathability, which helps to keep the skin dry and comfortable, and will not make the skin feel stuffy. It is suitable for making various products that come into direct contact with the skin, such as leather shoes, leather clothes, leather bags, etc.

[0028] 6. Easy to process: Calfskin is relatively thin and has a uniform texture. It is easy to cut, sew and process into shape. It can meet various complex design and production requirements. The products produced have smooth lines and beautiful shapes. DETAILED DESCRIPTION

[0029] Embodiment 1:

[0030] A process for manufacturing shoe upper leather based on Dutch cowhide, comprising the following processes:

[0031] Dutch calf hide was used as the raw hide, weighed, and the weight was increased by 130% for measurement (ie, 100 g was weighed and measured according to 100×130%=130 g).

[0032] Soaking: put the Dutch calf hide into a drum, add 300% water at 18°C ​​and 0.3% penetrant ProSpread (Proviera Biotech, USA), rotate for 5 minutes, stop for 55 minutes; rotate at 1 rpm; repeat once; drain;

[0033] Pre-soaking: put the soaked Dutch calf leather into a drum, add 200% water at 18°C, add 0.3% penetrant ProSpread (Proviera Biotech, USA), 0.1% degreasing agent ProDegreaze (Proviera Biotech, USA), 0.3% soda ash, rotate for 10 minutes, stop for 30 minutes; rotate at 2rpm; control the temperature at 19°C, pH 6.3-6.7, Baume degree 8; repeat 4 times; wash with water, and remove from the drum;

[0034] De-fleshing and trimming: De-fleshing and trimming are performed on a fleshing machine to remove the meat membrane; useless parts such as wisps and rotten edges are cut off; and the weight is weighed; the weight is used as the basis for adding materials in subsequent processes.

[0035] Main soaking: put the Dutch calf hide after pre-soaking, fleshing and trimming into a drum, add 200% water at 18°C, and rotate the drum at 3rpm; add 0.1% penetrant ProSpread (Proviera Biotech, USA), 0.3% soaking agent ProSoak (Proviera Biotech, USA), and 0.3% degreasing agent ProDegreaze (Proviera Biotech, USA), rotate for 10min, stop for 20min; control pH 6.3-6.7, rotate at 2rpm, repeat once; add 0.2% soda ash, adjust pH 9.5-10.5, rotate for 10min, stop for 20min; repeat 5 times, require full penetration, and the cut is milky white; wash with water, and remove from the drum;

[0036] Meat removal and trimming: Meat is removed on a meat remover to remove all meat membranes without leaving any loose meat; useless parts such as wisps and rotten edges are trimmed and weighed; the weight is used as the basis for adding materials in subsequent processes.

[0037] Enzyme dehairing: put the Dutch calf hide after main soaking, fleshing and trimming into a drum, add 100% of 24°C, the drum speed is 6rpm, and the pH is adjusted to 9.0-9.5; add 0.3% of penetrant ProSpread (Proviera Biotech, USA) and 0.6% of complex enzyme A (self-made, reference patent ZL201510347968.6), and rotate for 30 minutes; add 0.2% of keratinase K (Xiasheng Biotechnology Company), and rotate for 30 minutes; check the dehairing situation, if the dehairing rate is greater than 90%, enter the next process; otherwise, continue to rotate for 30 minutes; wash with water, filter the hair, and drain the liquid;

[0038] Liming: put Dutch calf hides with a hair removal rate of more than 90% into a drum, add 100% of 24°C water, and rotate the drum at 3rpm; add 0.3% of penetrant ProSpread (Proviera Biotech, USA) and 2% of lime, and rotate for 60min; add 150% of 24°C water and 0.15% of 30% sodium hydroxide solution, and rotate for 60min; then rotate for 5min, stop for 55min, and repeat 5 times; wash with water and remove from the drum;

[0039] Splitting and trimming: The splitting thickness is about 1.8mm. When trimming, cut off the fringe and rotten edges and weigh them.

[0040] Deliming: put the split Dutch calf hide into a drum, add 200% water at 30°C, add 0.3% penetrant ProSpread (Proviera Biotech, USA), add 0.7% ammonium-free deliming agent DLA (Dawei Technology Co., Ltd.), rotate for 15 minutes at 6 rpm; then add 0.7% ammonium-free deliming agent DLA (Dawei Technology Co., Ltd.), rotate for 15 minutes; adjust the pH to 8.0-8.5;

[0041] Softening: Continue to add ammonium-free softening enzyme CBK 0.2% (Dawei Technology Co., Ltd.), degreasing agent ProDegreaze 0.3% (Proviera Biotech, USA), rotate for 10 minutes, stop for 20 minutes; adjust the temperature to 30°C and pH 7.5-8.5, rotate for 10 minutes, stop for 20 minutes; repeat twice, take the buttocks incision and see that it is colorless to phenolphthalein reagent, which means that softening is complete; wash with water and remove from the drum;

[0042] Pickling: put the softened Dutch calf hide into a drum, add 100-200% water at 23°C, add 7% sodium chloride, rotate for 10 minutes, and rotate at 8rpm; adjust the Baume degree to ≥7; add 0.5% formic acid with a concentration of 85% diluted with 8 times normal temperature water during rotation, rotate for 30 minutes; add 0.2% concentrated sulfuric acid with a concentration of 98% diluted with 8 times normal temperature water, adjust the pH to 2.5-3.0, and rotate for 60 minutes;

[0043] Less chrome tanning: add 1% cationic oil XGS (Clariant Chemicals), rotate for 40 minutes, speed 8rpm; then add 0.5% chrome powder, rotate for 60 minutes; add 5% zeolite tanning agent BS (Tiger Company), rotate for 60 minutes; add 1.0% sodium formate, rotate for 60 minutes; then add baking soda in portions, slowly adjust the pH to 3.2-3.4; add 100% water, continue to add baking soda in portions, slowly adjust the pH to 3.8-4.2, and then rotate for 120 minutes; drain the liquid and remove the drum; let it stand for 3 days.

[0044] Squeezing and shaving: Classification, squeezing, shaving and trimming are carried out according to conventional processes. The shaving thickness is 0.95-1.0, and it is weighed as a measurement standard for subsequent chemical material consumption.

[0045] Rewetting: put the wet blue leather made of shaved Dutch calf hide into a drum, add 100% water at 23°C and 0.3% formic acid, adjust the pH to 2.5-3.0, and rotate for 10 minutes; add 0.3% penetrant ProSpread (ProvieraBiotech, USA) and 0.1% degreasing agent ProDegreaze (Proviera Biotech, USA), and rotate for 30 minutes; add 1% acid enzyme TN (Desail Chemical), and rotate for 90 minutes; drain and wash with ice water;

[0046] Primary neutralization: add 200% ice water, 2% neutralizer NSL (Bates Chemical), rotate for 10 minutes; add 0.5% tear-resistant oil F04 (ALPA, Italy), adjust pH to 4.8-5.2 with baking soda, rotate for 30 minutes; drain and wash with ice water;

[0047] One-time filling: add 3% of small molecule acrylic acid R35 (Tiger Company), rotate for 30 minutes; add 44% of medium molecule acrylic acid B (Tiger Company), rotate for 30 minutes; add 2% of macromolecule acrylic acid 007L (Barts Chemical), rotate for 30 minutes; add 0.5% of dispersant TM (Zhejiang Shenghui Chemical), rotate for 10 minutes; add 2% of betel nut tannin TDT (France SCRD Company) and 2% of synthetic tanning agent JHL (Zhejiang Shenghui Chemical), rotate for 30 minutes;

[0048] Chrome-free retanning: add 150% ice water, add 1% formic acid, adjust pH 2.8-3.5, rotate for 10 minutes; add 0.5% tear-resistant oil F04 (Italy ALPA Company), 3% zeolite tanning agent BS (Tiger Company), rotate for 60 minutes; add 1-2% sodium formate, rotate for 10 minutes; add 0.5% baking soda, adjust pH 3.8-4.2, rotate for 10 minutes, stop for 50 minutes; repeat 3 times; drain;

[0049] Secondary neutralization: add 150% ice water, 2% neutralizer NSL (Barts Chemical), 1% sodium formate, and rotate for 10 minutes; add 0.5% baking soda, adjust pH 4.5-5.0, and rotate for 40 minutes; drain;

[0050] Secondary filling: add 3-5% of small molecule acrylic acid R35 (Tiger Company), and rotate for 30 minutes; add 4% of medium molecule acrylic acid B4 (Tiger Company), and rotate for 30 minutes; add 2% of macromolecular acrylic acid 007L (Barts Chemical), and rotate for 30 minutes; add dicyandiamide BLE 2% (Shanghai Daming Chemical), synthetic tanning agent JHL 2% (Zhejiang Shenghui Chemical), phenolic synthetic tanning agent MLB 2% (BASF Chemical), and rotate for 30 minutes; add dispersant TM 1% (Zhejiang Shenghui Chemical), retanning agent PN 2% (Tiger Chemical), betel nut tannin GMB 3% (France SCRD Company), and rotate for 10 minutes; add leveling agent LU 1% (Derui Company), dye RHS 3%, and rotate for 60 minutes; make up 150% of 50℃ water, add 1.0% formic acid in batches, adjust the pH to 3.8-4.2, and rotate for 10 minutes; drain;

[0051] Grease: add 150% water at 50℃, add 0.5% tear-resistant oil F04 (Italy ALPA Company), 2% amphoteric acrylic acid TGR (Templer Company), and rotate for 10-30 minutes; add 2% synthetic oil DXV (Templer Company), 1% sulfonated synthetic oil H50 (Italy ALPA Company), 1% neat's foot oil CK (Tiger Chemical), and rotate for 60 minutes; add 1.0% formic acid, adjust the pH to 3.5-3.8; rotate for 10-30 minutes; drain;

[0052] Color fixation: add 150% of 50°C water, add 0.5% of dye RHS, and rotate for 15 minutes; add 0.5% of formic acid in portions, adjust the pH to 3.5-3.8, and rotate for 15 minutes; add 1% of cationic fatliquor GS (Clariant), and rotate for 15 minutes; drain the liquid, wash with water; and remove from the drum.

[0053] Drying and finishing: Dry, stretch, soften and tumble according to conventional processes to make the Dutch calf leather have a horizontal content of about 14-18%, soft and flat, so as to be suitable for finishing.

[0054] Finishing: The finishing process is primer → ironing 1 → top coating → ironing 2 → softening → top coating → ironing 3 → softening → finished product.

[0055] The coating chemical materials are all from Starr, including: the primer formula is: 300 parts of water, 50 parts of water-based penetrant PT-4235, 100 parts of water-based polyurethane AP-39.A; the coating amount is about 5g;

[0056] The top coating formula is: 300 parts of water, 50 parts of water-based penetrant PT-4235, 100 parts of medium-soft comprehensive resin RC-22-452, 100 parts of high-property acrylic resin A-946, 100 parts of high-property polyurethane resin RU-73-901, 50 parts of non-ionic polyurethane resin RU-77-197, 100 parts of matting agent WD-77-401, 100 parts of pigment paste, 50 parts of board wax FI-50; the coating amount is about 5g;

[0057] The top coating formula is: 300 parts of water, 300 parts of high gloss polyurethane resin WT-42-518, 200 parts of matte polyurethane resin WT-13-097, 10 parts of cross-linking agent XR-13-906, and 10 parts of hand feeling agent WF-5230; the coating amount is about 2g;.

[0058] Ironing is carried out on a plate ironing machine. The process parameters for ironing 1 are: the surface temperature of the bright board is 100°C, the pressure is 50kg, and the time is 2s; the process parameters for ironing 2 and ironing 3 are: the surface temperature of the bright board is 100°C, the pressure is 30kg, and the time is 2s;

[0059] Hammering: It is carried out in a stainless steel octagonal tumbling drum. The parameters of the tumbling drum are: speed 15r / min, time 6h, the drum is set to automatic intermittent forward and reverse rotation, the moisture content of the crust leather is 20%; the temperature inside the drum is automatically controlled at 25℃.

[0060] Softening: It is operated on an oscillating softening machine. The parameters of the oscillating softening machine are: transmission speed 9.5m / min, level 5.

[0061] Embodiment 2:

[0062] A process for manufacturing shoe upper leather based on Dutch cowhide, comprising the following processes:

[0063] Dutch calf hide was used as the raw hide, weighed, and the weight was increased by 130% for measurement (ie, 100 g was weighed and measured according to 100×130%=130 g).

[0064] Soaking: put the Dutch calf hide into a drum, add 300% water at 18-21°C and 0.3% penetrant ProSpread (Proviera Biotech, USA), rotate for 5 minutes, stop for 55 minutes; rotate at 2 rpm; repeat twice; drain;

[0065] Pre-soaking: put the soaked Dutch calf leather into a drum, add 200% water at 21°C, add 0.3% penetrant ProSpread (Proviera Biotech, USA), 0.1% degreasing agent ProDegreaze (Proviera Biotech, USA), 0.3% soda ash, rotate for 10 minutes, stop for 30 minutes; rotate at 3rpm; control the temperature at 19-25°C, pH 6.3-6.7, Baume degree 9; repeat 6 times; wash with water, and remove from the drum;

[0066] De-fleshing and trimming: De-fleshing and trimming are performed on a fleshing machine to remove the meat membrane; useless parts such as wisps and rotten edges are cut off; and the weight is weighed; the weight is used as the basis for adding materials in subsequent processes.

[0067] Main soaking: put the Dutch calf hide after pre-soaking, fleshing and trimming into a drum, add 200% water at 21°C, and rotate the drum at 3rpm; add 0.1% penetrant ProSpread (Proviera Biotech, USA), 0.3% soaking agent ProSoak (Proviera Biotech, USA), and 0.3% degreasing agent ProDegreaze (Proviera Biotech, USA), rotate for 10min, stop for 20min; control pH 6.3-6.7, rotate at 3rpm, repeat 3 times; add 0.4% soda ash, adjust pH 9.5-10.5, rotate for 10min, stop for 20min; repeat 8 times, requiring full penetration and milky white cut; wash with water and remove from drum;

[0068] Meat removal and trimming: Meat is removed on a meat remover to remove all meat membranes without leaving any loose meat; useless parts such as wisps and rotten edges are trimmed and weighed; the weight is used as the basis for adding materials in subsequent processes.

[0069] Enzyme dehairing: put the Dutch calf hide after main soaking, fleshing and trimming into a drum, add 100% of 28℃, the drum speed is 8rpm, and the pH is adjusted to 9.0-9.5; add 0.3% of penetrant ProSpread (Proviera Biotech, USA) and 0.8% of complex enzyme A (self-made, reference patent ZL201510347968.6), and rotate for 30 minutes; add 0.4% of keratinase K (Xiasheng Biotechnology Company), and rotate for 30 minutes; check the dehairing situation, if the dehairing rate is greater than 90%, enter the next process; otherwise, continue to rotate for 60 minutes; wash with water, filter the hair, and drain the liquid;

[0070] Liming: put Dutch calf hides with a hair removal rate of more than 90% into a drum, add 100% of 26°C water, and rotate the drum at 5 rpm; add 0.3% of penetrant ProSpread (Proviera Biotech, USA) and 2% of lime, and rotate for 60 minutes; add 150% of 26°C water and 0.2% of 30% sodium hydroxide solution, and rotate for 60 minutes; then rotate for 5 minutes, stop for 55 minutes, and repeat 8 times; wash with water and remove from the drum;

[0071] Splitting and trimming: The splitting thickness is about 2.0mm. When trimming, cut off the fringe and rotten edges and weigh them.

[0072] Deliming: Put the split Dutch calf hide into a drum, add 200-250% water at 32°C, add 0.3% penetrant ProSpread (Proviera Biotech, USA), add 1.0% ammonium-free deliming agent DLA (Dawei Technology Co., Ltd.), rotate for 30 minutes at 6 rpm; then add 1.0% ammonium-free deliming agent DLA (Dawei Technology Co., Ltd.), rotate for 30 minutes; adjust the pH to 8.0-8.5;

[0073] Softening: Continue to add ammonium-free softening enzyme CBK 0.5% (Dawei Technology Co., Ltd.), degreasing agent ProDegreaze 0.3% (Proviera Biotech, USA), rotate for 10 minutes, stop for 20 minutes; adjust the temperature to 32°C, pH 7.5-8.5, rotate for 10 minutes, stop for 20 minutes; repeat 3 times, take the buttocks incision and see that it is colorless to phenolphthalein reagent, which means that the softening is complete; wash with water and remove from the drum;

[0074] Pickling: put the softened Dutch calf hide into a drum, add 200% water at 25℃, add 10% sodium chloride, rotate for 10 minutes, and rotate at 8rpm; adjust the Baume degree ≥ 7; add 1.5% formic acid with a concentration of 85% diluted with 10 times normal temperature water during rotation, rotate for 30 minutes; add 0.8% concentrated sulfuric acid with a concentration of 98% diluted with 10 times normal temperature water, adjust the pH to 2.5-3.0, and rotate for 180 minutes;

[0075] Less chrome tanning: add 1% cationic oil XGS (Clariant Chemicals), rotate for 40 minutes, speed 8rpm; then add 2.5% chrome powder, rotate for 60 minutes; add 10% zeolite tanning agent BS (Tiger Company), rotate for 60 minutes; add 2.0% sodium formate, rotate for 60 minutes; then add baking soda in portions, slowly adjust the pH to 3.2-3.4; add 150% water, continue to add baking soda in portions, slowly adjust the pH to 3.8-4.2, and then rotate for 180 minutes; drain the liquid and remove the drum; let it stand for 7 days.

[0076] Squeezing and shaving: Classification, squeezing, shaving and trimming are carried out according to conventional processes. The shaving thickness is 0.95-1.0, and it is weighed as a measurement standard for subsequent chemical material consumption.

[0077] Rewetting: put the wet blue leather made of shaved Dutch calf hide into a drum, add 200% water at 23°C and 0.3% formic acid, adjust the pH to 2.5-3.0, and rotate for 30 minutes; add 0.3% penetrant ProSpread (ProvieraBiotech, USA) and 0.1% degreasing agent ProDegreaze (Proviera Biotech, USA), and rotate for 60 minutes; add 1% acid enzyme TN (Desail Chemical), and rotate for 90-150 minutes; drain and wash with ice water;

[0078] Primary neutralization: add 300% ice water, 3% neutralizer NSL (Bates Chemical), rotate for 10 minutes; add 1% tear-resistant oil F04 (Alpa Company, Italy), adjust pH to 4.8-5.2 with baking soda, rotate for 90 minutes; drain and wash with ice water;

[0079] One-time filling: add 5% of small molecule acrylic acid R35 (Tiger Company), rotate for 90 minutes; add 46% of medium molecule acrylic acid B (Tiger Company), rotate for 90 minutes; add 4% of macromolecule acrylic acid 007L (Barts Chemical), rotate for 90 minutes; add dispersant TM 1% (Zhejiang Shenghui Chemical), rotate for 30 minutes; add betel nut tannin extract TDT 3% (France SCRD Company), synthetic tanning agent JHL 3% (Zhejiang Shenghui Chemical), rotate for 90 minutes;

[0080] Chrome-free retanning: add 150% ice water, add 3% formic acid, adjust pH 2.8-3.5, rotate for 10-30 minutes; add tear-resistant oil F04 1% (Italy ALPA Company), 8% zeolite tanning agent BS (Tiger Company), rotate for 60 minutes; add 2% sodium formate, rotate for 10-30 minutes; add 1.0% baking soda, adjust pH 3.8-4.2, rotate for 10 minutes, stop for 50 minutes; repeat 5 times; drain;

[0081] Secondary neutralization: add 200% ice water, 3% neutralizer NSL (Barts Chemical), 2% sodium formate, and rotate for 30 minutes; add 1.0% baking soda, adjust pH 4.5-5.0, and rotate for 60 minutes; drain;

[0082] Secondary filling: add 5% of small molecule acrylic acid R35 (Tiger Company), and rotate for 90 minutes; add 6% of medium molecule acrylic acid B4 (Tiger Company), and rotate for 90 minutes; add 4% of large molecule acrylic acid 007L (Barts Chemical), and rotate for 90 minutes; add 3% of dicyandiamide BLE (Shanghai Daming Chemical), 3% of synthetic tanning agent JHL (Zhejiang Shenghui Chemical), and 3% of phenolic synthetic tanning agent MLB (BASF Chemical), and rotate for 90 minutes; add dispersant TM 2% (Zhejiang Shenghui Chemical), 3% of retanning agent PN (Tiger Chemical), and 5% of betel nut tannin GMB (France SCRD Company), and rotate for 30 minutes; add leveling agent LU 2% (Derui Company), dye RHS 5%, and rotate for 60 minutes; add 150% of 50℃ water, add 2.0% of formic acid in batches, adjust the pH to 3.8-4.2, and rotate for 30 minutes; drain;

[0083] Grease: add 200% water at 60℃, add 1% tear-resistant oil F04 (Italy ALPA Company), 3% amphoteric acrylic acid TGR (Templer Company), and rotate for 10-30 minutes; add 4% synthetic oil DXV (Templer Company), 3% sulfonated synthetic oil H50 (Italy ALPA Company), 3% neat's foot oil CK (Tiger Chemical), and rotate for 60 minutes; add 2.0% formic acid, adjust the pH to 3.5-3.8; rotate for 30 minutes; drain;

[0084] Color fixation: add 200% water at 60°C, add dye RHS 1.0%, rotate for 30 minutes; add formic acid 1.5% in batches, adjust pH 3.5-3.8, rotate for 30 minutes; add cationic fatliquor GS 2% (Clariant), rotate for 30 minutes; drain, wash with water; remove from drum.

[0085] Drying and finishing: Dry, stretch, soften and tumble according to conventional processes to make the Dutch calf leather have a horizontal content of about 18%, making it soft and flat, so that it is suitable for finishing.

[0086] Finishing: The finishing process is primer → ironing 1 → top coating → ironing 2 → softening → top coating → ironing 3 → softening → finished product.

[0087] The coating chemical materials are all from Starr, including: the primer formula is: 500 parts of water, 100 parts of water-based penetrant PT-4235, 200 parts of water-based polyurethane AP-39.A; the coating amount is about 15g;

[0088] The top coating formula is: 500 parts of water, 100 parts of water-based penetrant PT-4235, 200 parts of medium-soft comprehensive resin RC-22-452, 200 parts of high-property acrylic resin A-946, 200 parts of high-property polyurethane resin RU-73-901, 100 parts of non-ionic polyurethane resin RU-77-197, 200 parts of matting agent WD-77-401, 200 parts of pigment paste, 100 parts of board wax FI-50; the coating amount is about 5-10g;

[0089] The top coating formula is: 500 parts of water, 500 parts of high gloss polyurethane resin WT-42-518, 300 parts of matte polyurethane resin WT-13-097, 50 parts of cross-linking agent XR-13-906, and 50 parts of hand feeling agent WF-5230; the coating amount is about 5g;.

[0090] Ironing is carried out on a plate ironing machine. The process parameters for ironing 1 are: the surface temperature of the bright board is 100°C, the pressure is 50kg, and the time is 2s; the process parameters for ironing 2 and ironing 3 are: the surface temperature of the bright board is 100°C, the pressure is 30kg, and the time is 2s;

[0091] Hammering: It is carried out in a stainless steel octagonal tumbling drum. The parameters of the tumbling drum are: speed 15r / min, time 6h, the drum is set to automatic intermittent forward and reverse rotation, the moisture content of the crust leather is 20-25%; the temperature inside the drum is automatically controlled at 25-30℃.

[0092] Softening: It is operated on an oscillating softening machine. The parameters of the oscillating softening machine are: transmission speed 9.5m / min, level 5.

[0093] The upper leather of calfskin obtained by the technical solution of the present application was tested, as follows:

[0094]

[0095] The above is only a specific implementation of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial changes to the present invention using this concept shall be deemed as an infringement of the protection scope of the present invention.

Claims

1. A method for preparing shoe upper leather based on Dutch calf leather, characterized in that: The process includes the following steps: soaking → pre-soaking → fleshing and trimming → main soaking → fleshing and trimming → enzyme dehairing → liming → splitting and trimming → deliming → softening → pickling → less chrome tanning → squeezing and shaving → rewetting → primary neutralization → primary filling → chrome-free retanning → secondary neutralization → secondary filling → fatliquoring → color fixation → drying and finishing → painting; wherein, Pre-soaking: put the soaked Dutch calf leather into a drum, add 200% water at 18-21℃, add 0.3% penetrant, 0.1% degreasing agent, 0.3% soda ash, rotate for 10 minutes, stop for 30 minutes; rotate at 2-3rpm; control the temperature at 19-25℃, pH 6.3-6.7, Baume degree 8-9; repeat 4-6 times; wash with water, and remove from the drum; Main soaking: put the pre-soaked, fleshed and trimmed Dutch calf hide into a drum, add 200% water at 18-21℃, and rotate the drum at 3rpm; add 0.1% penetrant, 0.3% soaking agent, and 0.3% degreasing agent, rotate for 10min, and stop for 20min; control the pH at 6.3-6.7, rotate at 2-3rpm, and repeat 1-3 times; add 0.2-0.4% soda ash, adjust the pH to 9.5-10.5, rotate for 10min, and stop for 20min; Repeat 5-8 times, requiring full penetration and milky white incision; wash with water and remove the drum; Enzyme dehairing: put the Dutch calf hide after main soaking, fleshing and trimming into a drum, add 100% of 24-28℃, the drum speed is 6-8rpm, adjust the pH to 9.0-9.5; add 0.3% penetrant, 0.6-0.8% complex enzyme A, rotate for 30 minutes; add 0.2-0.4% keratinase K, rotate for 30 minutes; Check the depilation situation. If the depilation rate is greater than 90%, proceed to the next process; otherwise, continue to rotate for 30-60 minutes; Wash with water, filter wool, drain; Deliming: put the split Dutch calf hide into a drum, add 200-250% water at 30-32℃, add 0.3% penetrant, add 0.7-1.0% ammonium-free deliming agent, rotate for 15-30 minutes, and the speed is 6rpm; Then add 0.7-1.0% of ammonium-free deashing agent and rotate for 15-30 minutes; adjust the pH to 8.0-8.5; Softening: Continue to add 0.2-0.5% ammonium-free softening enzyme and 0.3% degreasing agent, rotate for 10 minutes, stop for 20 minutes; adjust the temperature to 30-32℃, pH 7.5-8.5, rotate for 10 minutes, stop for 20 minutes; repeat 2-3 times, take the buttocks cut and see that it is colorless to phenolphthalein reagent, which means the softening is complete; wash with water and remove from the drum; Finishing: The finishing process is primer → ironing 1 → top coating → ironing 2 → softening → top coating → ironing 3 → softening → finished product.

2. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The soaking process comprises: putting Dutch calf hide into a rotary drum, adding 300% water at 18-21° C. and 0.3% penetrant, rotating for 5 minutes, stopping for 55 minutes, rotating at 1-2 rpm, repeating 1-2 times, and draining the liquid.

3. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The liming process comprises the following steps: putting Dutch calf hides with a hair removal rate of more than 90% into a rotary drum, adding 100% of 24-26° C. sodium hydroxide solution, rotating the drum at a speed of 3-5 rpm; adding 0.3% of a penetrant and 2% of lime, rotating the drum for 60 minutes; adding 150% of 24-26° C. water and 0.15-0.2% of a 30% sodium hydroxide solution, rotating the drum for 60 minutes; then rotating the drum for 5 minutes, stopping the drum for 55 minutes, and repeating the process for 5-8 times; washing the drum with water, and removing the drum from the drum.

4. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The pickling method comprises the following steps: putting softened Dutch calf hide into a rotary drum, adding 100-200% water at 23-25° C., adding 7-10% sodium chloride, rotating for 10 minutes, and rotating at a speed of 8 rpm; adjusting the Baume degree to be ≥7; adding 0.5-1.5% formic acid with a concentration of 85% diluted with 8-10 times normal temperature water during rotating, and rotating for 30 minutes; adding 0.2-0.8% concentrated sulfuric acid with a concentration of 98% diluted with 8-10 times normal temperature water, adjusting the pH to 2.5-3.0, and rotating for 60-180 minutes.

5. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The chrome-less tanning process comprises the following steps: adding 1% of cationic oil, rotating for 40 minutes, and rotating at a speed of 8 rpm; then adding 0.5-2.5% of chrome powder, and rotating for 60 minutes; adding 5-10% of zeolite tanning agent, and rotating for 60 minutes; adding 1.0-2.0% of sodium formate, and rotating for 60 minutes; then adding baking soda in portions, and slowly adjusting the pH value to 3.2-3.4; adding 100-150% of water, continuing to add baking soda in portions, and slowly adjusting the pH value to 3.8-4.2, and then rotating for 120-180 minutes; draining the liquid, removing the drum, and standing for 3-7 days.

6. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The one-time filling comprises: adding 3-5% of small molecule acrylic acid R35, rotating for 30-90 minutes; adding 4-6% of medium molecule acrylic acid, rotating for 30-90 minutes; adding 2-4% of macromolecular acrylic acid, rotating for 30-90 minutes; adding 0.5-1% of dispersant, rotating for 10-30 minutes; adding 2-3% of betel nut tannin extract and 2-3% of synthetic tanning agent, rotating for 30-90 minutes.

7. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The chrome-free retanning comprises the following steps: adding 150% ice water, adding 1-3% formic acid, adjusting the pH value to 2.8-3.5, rotating for 10-30 minutes; adding 0.5-1% tear-resistant oil, 3-8% zeolite tanning agent, rotating for 60 minutes; adding 1-2% sodium formate, rotating for 10-30 minutes; adding 0.5-1.0% baking soda, adjusting the pH value to 3.8-4.2, rotating for 10 minutes, and stopping for 50 minutes; repeating for 3-5 times; and draining the liquid.

8. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The secondary filling includes: adding 3-5% of small molecule acrylic acid and rotating for 30-90 minutes; adding 4-6% of medium molecule acrylic acid and rotating for 30-90 minutes; adding 2-4% of large molecule acrylic acid and rotating for 30-90 minutes; Add 2-3% dicyandiamide, 2-3% synthetic tanning agent, 2-3% phenol synthetic tanning agent, and rotate for 30-90 minutes; add 1-2% dispersant, 2-3% retanning agent, 3-5% betel nut tannin, and rotate for 10-30 minutes; add 1-2% leveling agent and 3-5% dye, and rotate for 60 minutes; add 150% 50°C water, add 1.0-2.0% formic acid in batches, adjust the pH to 3.8-4.2, and rotate for 10-30 minutes; drain the liquid.

9. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The top coating formula is: 300-500 parts of water, 50-100 parts of water-based penetrant, 100-200 parts of medium-soft comprehensive resin, 100-200 parts of high-property acrylic resin, 100-200 parts of high-property polyurethane resin, 50-100 parts of non-ionic polyurethane resin, 100-200 parts of matting agent, 100-200 parts of pigment paste, and 50-100 parts of release wax; the coating amount is about 5-10g.

10. The method for preparing shoe upper leather based on Dutch calf leather according to claim 1, characterized in that: The top coating formula is: 300-500 parts of water, 300-500 parts of high-gloss polyurethane resin, 200-300 parts of matte polyurethane resin, 10-50 parts of cross-linking agent, and 10-50 parts of hand feeling agent; the coating amount is about 2-5g.

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