Impregnation method of water-saving superfine fiber synthetic leather base cloth based on cationic waterborne polyurethane

Abstract

The invention discloses a water-saving superfine fiber synthetic leather base cloth impregnation method based on cationic water-based polyurethane. The impregnation method includes the steps that 100 parts of the water-based alkali-hydrolysis-resisting cationic polyurethane with the solid content ranging from 20% to 50%, 0 part to 50 parts of water, 5 parts to 10 parts of color paste and 1 part to 3 parts of thickening agents are evenly mixed, and water-based impregnation slurry is prepared; superfine fiber non-woven fabric is immersed into the water-based polyurethane slurry to be impregnated, and finally placed into a 10%-15% sodium hydroxide aqueous solution to be subjected to synchronous solidification and alkali-weight-reduction treatment, wherein the solidification and weight-reduction bath temperature ranges from 95 DEG C to 100 DEG C, the solidification and weight-reduction time ranges from 30 min to 60 min, under the alkali condition, the cationic polyurethane is solidified in superfine fiber synthetic leather and forms a foam structure, and a sea component PET is dissolved under the effect of hot alkali to achieve weight reduction; the base cloth obtained after alkali weight reduction is washed, dried and buffed, and finally superfine fiber synthetic leather is obtained through dry-method surface making and after-treatment. According to the impregnation method, the water-based polyurethane replaces solvent type resin to be used for impregnating the superfine fiber synthetic leather base cloth, and ecological environmental protection is achieved; the foam structure is formed through the characteristic that the cationic polyurethane is rapidly solidified when encountering alkali, and the foam feeling and the fullness of the finished leather are improved; the solidification and alkali-weight-reduction process is completed in one bath, and therefore water consumption, energy consumption and technologies are reduced.

Description

technical field [0001] The invention relates to a method for impregnating a water-saving superfine fiber synthetic leather base cloth based on cationic waterborne polyurethane, which belongs to the field of synthetic leather manufacture. Background technique [0002] As the latest generation of synthetic leather products, microfiber synthetic leather has excellent resilience, softness, imitation, and air permeability. It is replacing genuine leather and ordinary synthetic leather to meet the demand for high-end products in domestic and foreign markets. , reflecting the main direction of synthetic leather technology development. Microfiber can be divided into fixed-island fiber and indeterminate-island fiber. Correspondingly, the manufacturing process of superfine fiber synthetic leather is divided into indeterminate-island process and fixed-island process. The process flow is as follows: [0003] (i) Adventitious island process: adventitious island sea-island fiber → needle...

AI Technical Summary

Problems solved by technology

Chinese patent CN201110028118.1 reports "a kind of waterborne polyurethane superfine fiber synthetic leather and its preparation method". It is impregnated with microfiber base cloth, but the base cloth needs to be squeezed repeatedly during the impregnation process, and the cells are easy to break; in addition, when the viscosity is low, the life of the foam after foam stabilization is short, and when the viscosity is high, it is difficult to penetrate, and the cell structure is uniform Difficult to control, and the method needs to coagulate in water, still producing impregnated wastewater

The chemical foaming method is difficult to realize because there is no foaming agent suitable for the waterborne polyurethane system at present.