国内美女直播视频,日韩人妻中文字幕精选,国产熟女av中文字幕,哦黑鸡巴用力插视频,亚洲av永久精品,国产午夜一区二区,午夜精品久久久久蜜桃,国产亚洲av综合人人澡精品,中文字幕日韩乱码在线

Commonly used leather tanning agents are: chrome tanning agent, zirconium tanning agent, aluminum tanning agent, vegetable tanning agent, oil tanning agent, etc.

Tanning with zirconium tanning agents began in the early 1930s. Compared with aluminum salt, iron salt and chromium salt, it is a new type of inorganic tanning agent. Its main characteristics are that the tanned leather is pure white, with good filling performance, and the tanned leather feels full and strong. Common zirconium salts include zirconium sulfate and zirconium chloride. Because its tanning performance is better than that of zirconium chloride, zirconium sulfate is commonly used. Tanning generally adopts the method of dry powder and pickling.

Zirconium sulfate is a white crystalline powder and is irritating. Mainly used as protein deposition agent, tanning agent for white leather, wrinkled leather and other leather. It can also be used as catalyst and friction reducer. It is used as a tanning agent for white leather to make the leather surface delicate, rich and elastic.

Zirconium sulfate is used for retanning of chrome tanned leather, and it cooperates with sulfone bridge tanning agent to replace tannin extract for tanning shoe lining, furniture leather, and sole leather. The finished product has detailed pores, plump and elastic. And has excellent filling and wear resistance.