Chrome-free tanning method of alligator skin

Abstract

The invention provides a chrome-free tanning method of alligator skin. The chrome-free tanning method comprises the following steps of (1) adding water and sodium chloride to a rotary drum or a paddle vat, adding a pickling alligator skin blank after the sodium chloride is dissolved, rotating the rotary drum or paddling a paddle plate for 5-10 minutes, and regulating the pH value of a mixed solution inside the rotary drum or the paddle vat to 3.4-3.7; (2) adding an organic phosphonium salt tanning agent, an alcamines compound and fatty aldehyde to the rotary drum or the paddle vat, then rotating the rotary drum or paddling the paddle plate for 10-20 minutes, standing for 30-60 minutes, and repeating the operation of rotating the rotary drum or paddling the paddle plate and standing till the alligator skin blank is fully impregnated; (3) regulating the pH value of the mixed solution inside the rotary drum or the paddle vat to 5.8-6.2, then rotating the rotary drum or paddling the paddle plate for 5-10 minutes, standing for 30-60 minutes, and repeating the operation of rotating the rotary drum or paddling the paddle plate and standing for 3-5 times, then standing for 6-12 hours, and then completely discharging the mixed solution; (4) adding the water and an oxidizing agent to the rotary drum or the paddle vat, then rotating the rotary drum or paddling the paddle plate for 5-10 minutes, standing for 30-60 minutes, and repeating the operation of rotating the rotary drum or paddling the paddle plate and standing for 3-5 times.

Description

technical field [0001] The invention belongs to the field of crocodile skin tanning, in particular to a chrome-free tanning method of crocodile skin. Background technique [0002] Alligator leather can be called "platinum" in leather. Its natural gradient grid texture gives it a unique appearance. Alligator leather is strong and has a good luster. It is a rare, precious and special leather raw material. The tanning process of crocodile skin is to process crocodile skin through fleshing, soaking, descaling, liming, deliming, softening, bleaching, pickling, tanning, neutralization, retanning, dyeing, fatliquoring, and finishing operations. Made into leather. At present, enterprises mainly use chrome tanning agent to tan crocodile skin. During the tanning process, the chrome tanning agent is not fully absorbed by the crocodile skin blank. After tanning, about 10% of chromium enters the wastewater, and the chromium-containing wastewater will cause great harm to the environment....

AI Technical Summary

Problems solved by technology

Adopt existing method to tan crocodile skin with organic phosphonium salt, there is the penetrability of organic phosphonium salt tanning agent in crocodile skin poor, the problem that organic phosphonium salt tanning agent combines with crocodile skin is difficult, in order to strengthen organic phosphonium salt in tanning process The penetration of tanning agent into the crocodile skin needs to increase the intensity of mechanical action, and the increase of mechanical action intensity will cause the grain surface of the crocodile skin to be worn away, destroying the grain gloss and the natural gradient checkered concave-convex texture of the crocodile skin