Glycolic Acid in Leather

Glycolic Acid for Leather Dyeing and Tanning

The leather industry depends on glycolic acid as a dyeing and tanning agent to achieve high-quality results because it:

  • Removes calcium oxide (CaO) efficiently in deliming
  • Is a powerful chrome complexant for pickling
  • Offers economic advantages due to reduced consumption of expensive dyes

Additionally, the nonvolatile, biodegradable glycolic acid:

  • Offers better dye color matching, color distribution, and color intensity
  • Has low corrosiveness
  • Offers an improved safety profile over many other acids

Glycolic Acid Enhances Leather Dyeing and Tanning Processes

Glycolic acid 70% tech grade is a solution of 70% glycolic acid and 30% water, useful in processes that require pH control and low volatility.

  • In tanning, glycolic acid is efficient for bath pH adjustment, which is critical in the production of sole leather and other vegetable tanning. Its sodium salt is effective as a masking agent.
  • In deliming, glycolic acid penetrates hides rapidly to reduce operation time. Its properties improve grain quality by eliminating excessive pelt swelling that causes wrinkles and reduces tear resistance.
  • In pickling, glycolic acid forms metal complexes with chrome and alum mordants, which is beneficial in fur and leather finishing.
  • In dyeing, the low volatility of glycolic acid requires lower usage than volatile agents like acetic and formic acids; heat does not produce corrosive fumes, and pH levels are easier to maintain.

Glycolic Acid: The Best Choice for Dyeing

In several pilot tests that compared the use of glycolic acid with formic acid:

  • Articles dyed with glycolic acid offered a more intense color hue
  • Dye usage was reduced when glycolic acid was used in processing
  • Hides dyed with glycolic acid were softer
  • The physical properties of leather were not significantly changed when using glycolic acid