Aldehyd AG

Aldehyd AG is an auxiliary agent for the leather industry.

It is an aldehyde agent for retanning mainly chromed leather. The product is also intended for individual and combined retanning (aluminum aldehyde or chromaldehyde) of fur leather. Aldehyd AG is a product of formaldehyde polymerization. It is a colorless to light straw liquid. It is characterized by excellent solubility in both hot and cold water. Methanol, ethanol, and acetone cause the separation of some components from the product. Aldehyd AG is resistant to acids, salts, and bases used in leather tanning. It forms mixtures with chromium, aluminum, and aldehyde tannins, dispersants, and anionic lubricants. Its advantage is a freezing point below -12°C, which facilitates the transportation and storage of this product. Aldehyd AG is a product that can be used for retanning alone. The thermal resistance of leathers tanned with its use is comparable to the level of thermal resistance of leathers tanned with formaldehyde or glutaraldehyde. Compared to formaldehyde tanning, Aldehyd AG leathers have slightly higher strength and fullness. Compared to glutaraldehyde tanning, a more favorable white color of the leather is achieved. Leathers tanned with Aldehyd AG have the typical advantages of aldehyde tanning, i.e., good resistance to sweat, bases, and detergents. An important property in the case of chrome tanning is its filling, softening, and smoothing effect on the leather. Chrome-tanned leathers with Aldehyd AG also have better dyeing properties. The product, with its weak leveling properties, does not cause excessive lightening of the leather dyed with anionic dyes. The affinity of Aldehyd AG to raw leather and chrome-tanned leather increases with higher pH, similar to the affinity of chrome tannins. The best preparation for retanning chrome-tanned leather is a mixture of Aldehyd AG with aluminum salts, ipoglin Al or Cr. The effect of filling is related to the improvement of the strength of retanned leathers.