Chrome-tanned, water-dyed and polished leather manufacturing method

Abstract

The invention discloses a chrome-tanned, water-dyed and polished leather manufacturing method, which comprises the following steps of: 1, in an alkali coating step, liming the head, neck and back by using high-concentration sodium sulphide lime unhairing paste and liming the belly with low-concentration sodium sulphide lime unhairing paste; 2, performing softening with a high liquor ratio in a softening step; 3, after a pickling step is finished, pouring 1 / 3 of waste liquor out, supplementing 1 / 3 of normal-temperature water, performing chrome-tanning on naked leather in a slightly-swelling state, and performing uniform cutting after the chrome-tanning; 4, performing pre-dyeing in re-tanning; 5, performing re-dyeing with a low liquor ratio in a filling step; 6, performing oiling re-dyeing in an oiling step; and 7, finishing and flattening the leather and polishing the leather on a polishing machine after the oiling re-dyeing. The method of the invention has the advantages of endowing the leather product with softness, compact grain side, fullness, high elasticity, clear pores, high air permeability, folding endurance, tensile resistance, natural gloss and tight side ribs, along with fewer steps, cost reduction and no influence on surrounding atmosphere, and is widely applied to the production of soft upper leather and glove leather by using cow leather, pigskin and sheepskin, particularly goat skin.

Description

Technical field: [0001] The invention relates to leather manufacturing, in particular to a method for making chrome-tanned water-dyed polished leather suitable for producing soft shoe upper leather, glove leather and garment leather from goatskin, cowhide, pigskin and sheepskin. Background technique: [0002] At present, the process of making traditional shoe upper leather is: pre-soaking → fleshing → drum soaking → alkali coating → liming → fleshing → dealkalization → softening → pickling → chrome tanning → smoothing → retanning → middle And→light dyeing→stretching→drying→Static to regain moisture→shock and soften→thin plate drying→edge trimming and grinding→dust removal and grinding surface→clean surface and ironing→spray middle layer slurry→spray surface layer slurry→spray fixative→heat Roll flat → finished product. This traditional processing method does not distinguish between high and low alkali in the alkali coating process, and the fibers in various parts of the raw...

AI Technical Summary

Problems solved by technology

This traditional processing method does not distinguish between high and low alkali in the alkali coating process, and the fibers in various parts of the raw hide cannot be fully dispersed, resulting in obvious differences between the sides and the head and neck; using a small liquid ratio in the softening process, the bare hide is easy to The length becomes longer, and vertical lines appear on the head and neck; chrome tanning is carried out directly after the pickling process, and the edge of the finished leather is easy to loosen; Slightly dyed, the color is not bright, and it needs to be sprayed to complete the finishing process

Not only is the process cumbersome and complicated, but also wastes chemical materials, the product quality is poor, the overall cost is high, and it will pollute the surrounding environment