Single-bath chrome tanning
What is single-bath chrome tanning?
Single-bath chrome tanning is a type of chrome tanning that’s used mainly to tan sole leather. During the 24-hour chrome tanning process, 1.5% of the chromium sulfate is absorbed into the hide, giving it a distinctive green-blue color. Outdoor leather is usually dyed using tanbark (a vegetable tanning method) which gives the leather a tan or light red-brown color. Sole leather’s color is only recognizable in the middle.
What is single-bath chrome-tanned leather like?
A certain pH value, chromium oxide content, basicity, and presence/type of masking need to be adhered to when tanning hides. Particular values for each of these aspects are important for creating a certain type of leather. The tanning agents used in the single-bath chrome tanning process make the leather smoother and more tear-resistant. Soft, smooth hides are the result of using chrome salts to pickle the untreated skins.
Single-bath vs. two-bath chrome tanning
The single-bath chrome tanning method was replaced by the two-bath method for a period. However, this method has gone out of fashion as the chromium (IV) compounds used in this process earned a bad reputation because of their toxicity.
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