US12151A - Improvement in compositions for unhairing hides - Google Patents

Description

UNITED STATES PATENT OFFICE.

ANDREW H. WARD, JR, or BOSTON, MASSAoHUSErrS, ASSIGNOR TO A. H. WARD, R, AND KIRK BOOTT.

IMPROVEMENT IN COMPOSITIONS FOR UNHAIRING HIDES.

Specification forming part of Letters Patent No. 12,151 dated January 2, 1855.

To all whom it may concern:

Be it known that 1, ANDREW H. WARD, J r., of Boston, in the county of Suffolk and State of Massachusetts, have invented a new and useful improvement in treating skins or hides, either previous to or during the process of tanning them and I do hereby declare that the sameis fully described and represented in the following specification.

The nature of my invention consists in the employment of a solution of carbonate and sulphate of soda, into which the hide or skin is to be steeped, for the purpose of loosening its hair and preparing said hide or skin for the application of tannin to it.

In carrying out my invention I make use of about two pounds of the carbonate of soda to one pound of the sulphate of soda, and fifteen gallons or one hundredand twenty pounds (avoidupois) of liquid or water, not confining myself strictly to such proportions, as the same may be somewhat varied and Still be productive of good results.

The hide or skin with the hair on is to be steeped for about two days in this solution. At the end of this time the hair may be removed from it by the usual process of beaming, the skin being left in a much better state for being tanned than when it is sweated or prepared with lime in the usual way.

In using soda-ash and lime, which of late has been the practice with some tanners in the preparation of skins for the reception of tannin, the skins have to be subjected to what is termed the drenching process in order to remove the lime. This drenching process con sists in immersing them in a solution of guano, pigeons or hens dung, and it is a very offensive and disagreeable mode of treatment.

The employment of soda-ash and lime generally requires about three weeks soaking of a skin in order to properly prepare it. With my improved mode of treating the skin it is prepared for the beamster in about two days. By my improvement the drenching ofthe skins is entirely avoided. As soon as the hair has been removed, or the Skin hasbeen beamed, it should be rinsed in clear water. It is then ready to be tanned. When the hair is removed by the solution of the carbonate and sulphate of Soda, the hide is left in a puffed up state, and with its pores opened for the reception of the tanning material, into which it is next to be put. After the hide has absorbed as much of the tanning-liquor as it apparently can, it may be removed from the tan-vat and rinsed in water, in order to remove the material that clogs the pores, as they will be found to be more or less clogged with foreign matter. When sufficiently rinsed the'skin may be again put into a solution of the depilatory salts or carbonate and sulphate of soda, which will have the effect of puffin g or swelling it and distending the pores. It may again be returned to the tanning-vat, where it will absorb more of the tanning-liquor. This process may be repeated until thehide is thoroughly tanned.

By the employment of the solution of carbonate and sulphate of soda for depilating a skin and preparing it for the reception of tannin it will be better tanned in eight days than in the great length of time (generally Several months) that is usually consumed by the ordinary process of liming, bathing, beaming, and tanning.

I have found that the use of carbonate of soda alone in depilating the hide is along and tedious operation, several weeks bein ,9; required to prepare the skin so that the hair maybe removed. By the addition of sulphate of Soda to the carbonate in Solution a wonderful acceleration of the process is effected.

I shall not pretend .to state the rationale of the action of the hydrated compound solution;

but as experience and observation have exhibited a result of great importance in the use of this compound solution in the manner as described, it is not necessary for me to go into chemical explanation of the manner in which the Solution of the carbonate and sulphate of Soda is made to operate so much more expeditiously on the skin than a solution of either the carbonate or sulphate alone.

The application'ofa compound solution of carbonate and sulphate of soda to hides and skins for the purpose of loosening their hair and preparing them for the reception of tannin.

In testimony whereof I have hereunto set my signature this 20th day of May, A. D. 1854.

ANDREW I-I. WARD, JR.