DE353131C - Process for neutralizing mineral tanned leathers - Google Patents

Description

Process for neutralizing mineral tanned leather. That The main patent relates to a process for neutralizing chrome leather, that is to say one mineral-tanned leather with soda or other carbonic acid salts of alkalis .or alkaline earths. The method is characterized in that when Neutralize formaldehyde or lower fatty acid at the same time as the substances mentioned or oxy-fatty acid salts of alkalis or alkaline earths are also used. Through this the effect of borax, the best neutralizing agent to date, is not only achieved, but exceeded.

According to the procedure Ües, i. Additional patent 353130 also have Al'kal'i- unid alkaline earth salts of other: weak inorganic acids than carbonic acid, such as B. sodium sulfite, in addition to the alkali or alkaline earth carbonates, a similar one Effect like the organic compounds mentioned above, so that they are also beneficial can be used in place of those when neutralizing.

It was now further found that Ida's stated neutralization process of the main patent, i.e. with alkali carbonates or alkaline earth carbonates, unrestricted co-use of formaldehyde or lower fatty acid or oxyfatty acid salts "of the alkalis . or alkaline earths of general use for any mineral tanning is capable. So with the same means, not only chrome leather, but also Iron and alum leather are advantageously neutralized.

Finally, just as for chrome, it is also mineral for any tanned leather, iron and alum leather, the substitute for the organic means mentioned by alkali and alkaline earth salts of weak inorganic acids, such as. B. sodium sulfite, applicable. Example i.

100 kg of pelts are tanned with one of the known iron tanning liquors and then moved 1 water, 4 kg of chalk and 1 kg of sodium acetate in a bath at Zoo, until neutralization has occurred, and then .with water: washed out.

Example 2.

100 kg of pelts become 3 kg of salt in a solution of 8 kg of potash alum tanned in 100 1 water, allowed to drain and in a bath of 1 zoo water, i kg of sodium sulfite and i kg of soda moved up. Neutralization has occurred, and then washed out with water.

The tanned alum and iron leather can also be used with the same excess of tanning broth dry up and only then the excess of tanning agent wash out and neutralize. 'in dit'serri' Fag one needs less Nei-It; alisierung = sxrittel.

Example 3.

100 kg pods are tanned with one of the well-known marriage tanning broths, drained and dried at a moderate temperature. 100 kg of dry leather are drummed with 500 liters of water in a tanning drum, where they soften, washed with more water and neutralized in a solution of 500 liters of Welsh, 0.5 kg of soda and 0.5 kg of sodium acetate.

Claims (1)

PATENT CLAIM: Modification of the process protected by patent 3522 $ 5 and additional patent 353130 , in which, instead of chrome leather, iron or alum leather with alkali or alkaline earth carbonates is used with the use of formaldehyde or lower fatty acid or oxyfatty acid salts of alkalis or alkaline earths or those of other weak inorganic acids than carbonic acid are neutralized.