Method for dyeing superfine fibre synthetic leather by utilizing tannin extract

Abstract

The invention discloses a method for dyeing superfine fibre synthetic leather by utilizing a tannin extract, comprising the following steps of: placing the superfine fibre synthetic leather into a revolving drum, adding hot water and the tannin extract to rotate; then, adding industrial formic acid to adjust the pH value of dyeing bath liquid, then, adding metal salt containing Fe<2+>, Fe<3+>, Co2 or Cu<2+> and a cross-linking agent, rotating and discharging the liquid; and repeatedly adding hot water into the revolving drum without the liquid to clean to obtain dyed superfine fibre syntheticleather. In the method, the natural tannin extract is selected to ensure that two components, i.e., a superfine fibre and polyurethane, of the superfine fibre synthetic leather are simultaneously colored, so that the problem of dyeing difference of the two components of the superfine fibre synthetic leather is solved; the metal salt containing Fe<2+>, Fe<3+>, Co2 or Cu<2+> and the tannin extract are added to generate compounds with different colors to dye the superfine fibre synthetic leather into different colors, and the metal salt can be used for fixing the tannin extract and improving thedyeing fastness; and the cross-linking agent can undergo a cross-linking reaction with the tannin extract to further fix the tannin extract and improve the dyeing fastness.

Description

technical field [0001] The invention relates to a production process of superfine fiber synthetic leather, in particular to a method for dyeing superfine fiber synthetic leather by using tannin extract. Background technique [0002] Tannin extract is a chemical product obtained by processing tannin-rich plant raw materials through water extraction and concentration. The main component is plant tannin. Plant tannins have a complex polyphenolic structure and mainly exist in the bark, root, leaf, and fruit of plants, and their content in plants is second only to cellulose, hemicellulose, and lignin. Tannin extract is usually brownish-yellow to tan, powdery or lumpy, and is mainly used for tanning natural leather. It is usually called vegetable tanning agent in the tanning industry. Because most of the tannin extract itself has a certain color, and the polyphenols in the tannin extract and the Fe 2+ , Fe 3+ 、Co 2 or Cu 2+ and other metal salts (such as FeSO 4 , CuCl 2 、Co...

AI Technical Summary

Problems solved by technology

However, the components of microfiber nonwovens need to be dyed in the later stage, and the coloring in the early stage will limit the product development in the later stage, and the product variety is single, which is difficult to meet the market requirements; A method and a combination of the technical advantages of (4) and (5), also reflects the technical defects of (4) and (5)