DE378450C - Process for the production of iron leather - Google Patents

Description

Process for the production of iron leather. It's already suggested been to impregnate hides first with iron salts and the so obtained wet Eisenleder then in a solution that contains alkali silicates in addition to fatty acid compounds contains to insert.

If one proceeds in this way, a part of what has been recorded occurs first Iron back out of the skin and forms insoluble iron silicate with the alkali silicate. The latter sticks to the skin and makes the leather brittle. It is that the same process that was carried out by E i t n e r when neutralizing chrome leather with a water glass was established (J e t t m r, Handbuch der Chromgerbung, 2nd edition igi2, P. 391 above). However, the problem mentioned is a little more obvious with chrome leather in appearance than with iron leather. In any case, it becomes a brittle, imperfect one and get useless leather.

In the present process, the iron silicate does not work as in previously known processes in the gel state, but in the sol state on the nakedness, and in this way one gains a non-brittle, very good one in a simple and accelerated way Iron leather.

If you add an ordinary glass of water to a solution of ferric chloride wanted to add, an excretion of insoluble iron silicate would immediately occur take place and tanning will not be possible with this mixture.

However, if you first dilute the commercially available water glass with water, for example with 8 to 10 times the amount, and this waterglass solution is added to the ferric chloride solution, thus no precipitation of iron silicate occurs, even if one part of ferric chloride is used Adds up to 4 parts of water glass. Rather, it is the iron silicate precipitate that initially arises completely in solution again on stirring.

The solutions of iron silicate prepared in this way are suitable, as already mentioned, excellent for the production of iron silicate leather. You stand out compared to solutions of basic iron salts, which are known to tan very slowly, also because they penetrate the skin particularly easily, i.e. very quickly to tan.

The invention can also be carried out in such a way that the skin first brings into the iron salt solution and after the iron salt solution through the If the skin has penetrated, slowly add the desired amount of water glass solution. In this way it is also prevented that insoluble iron silicate in the liquid arises.

Depending on one part of iron salt in the specified versions If up to 4 parts of water glass are used for tanning, leather is made of different types Properties, and the fuller and coarser the leather. the more water glass in the Relationship to the iron salt is used.

A combination of this iron silicate tanning with formaldehyde, as it is described for other iron salts in the Swiss patents 7- .84,9 and 75618, is not necessary in this case, although the Tanning effect here too through Fcrnialdeh @ - (1 is still to be fulfilled. The formaldehyde can again before, during or after the l @ isenger- 1 # for come. Atisfülirtiiig; lieisliie1r. i. In a clear solution of 10 kg of iron chloride and = o to 3o kg of water glass in @% 'as- ser, which in the manner described (ltirjli ver mix the iron salt solution with diluted stone Water glass is created, will be 100 kg Pelts tanned, washed out. if necessary greased, dried and prepared. z. ioo kg of pelts are produced in a ii) - solution of 10 kg ferric chloride and @ kg grain salt tanned in 100 1 water and 1 <.n @ r- ,; am with constant movement 2o to 3o kg Add dropwise 10% r'asser glass solution. permit. It will continue to move so long, bi: no more tannin absorbed by the skin men will. Then the leather comes out of it Tanning liquor taken out, rinsed with water washed, greased if necessary, dried and dressed.

Claims (1)

l'ATLXT ANSPRüciii: i. Process for the production of Eisenleder by means of solutions vc, n I? Iscii- salts and siliceous salts, e.g. B. What- serglas, characterized in that Q1-113 inan the flowering during the (lerbun means Add iron salts with @ vasserglass solutions by adding e @ it neither in one by mixing Eiseiisalzii, solution with diluted @@ 'asserglasl (* »t: ng obtained iron silicate solution tanned, i-) iler by first putting the nakedness in (lie Brings iron salt solution and then the Desired -Quantity "'water glass solution # -solution long- sam adds. z. Method of manufacture \ -, m 1, iron leather according to -linspru: li i, gekeniizeicli- net by using: "@ 1 <iehvden. especially formaldehyde or after the Eisengerbrng.