US 12,129,524 B2
Chrome-free tanning process of ecological leather
Yanan Wang, Chengdu (CN); Yue Yu, Chengdu (CN); Bi Shi, Chengdu (CN); Jianfei Zhou, Chengdu (CN); Yunhang Zeng, Chengdu (CN); and Wenhua Zhang, Chengdu (CN)
Assigned to SICHUAN UNIVERSITY, Chengdu (CN)
Appl. No. 18/681,096
Filed by SICHUAN UNIVERSITY, Chengdu (CN)
PCT Filed May 11, 2022, PCT No. PCT/CN2022/092095
§ 371(c)(1), (2) Date Feb. 5, 2024,
PCT Pub. No. WO2023/159773, PCT Pub. Date Aug. 31, 2023.
Claims priority of application No. 202210171515.2 (CN), filed on Feb. 24, 2022.
Prior Publication US 2024/0263257 A1, Aug. 8, 2024
Int. Cl. C14C 3/24 (2006.01); C14C 3/04 (2006.01); C14C 3/16 (2006.01); C14C 3/28 (2006.01)
CPC C14C 3/24 (2013.01) [C14C 3/04 (2013.01); C14C 3/16 (2013.01); C14C 3/28 (2013.01)] 15 Claims
 
1. A chrome-free tanning process of an ecological leather, comprising: tanning a pickled hide or skin as a raw material with a first tanning agent, adding sodium lignosulfonate to allow a reaction, and tanning a resulting product with a second tanning agent, wherein the first tanning agent has the structure of following Formula I:

OG Complex Work Unit Chemistry
Formula I, wherein R1 is —CH3, C2H5 or —C3H7; R2 is −H or CH3; R3 is —H or CH3; R4 is —CH3 or —C2H5 and n is 9-13; and
the second tanning agent has the structure of following Formula II:

OG Complex Work Unit Chemistry
Formula II, wherein M is Al or Zr and n is 19-20.