US300352A - Samuel s - Google Patents

Description

linrrnn States Patent (Clarion.

SAMUEL S. EDDY, OF ROCHESTER, NEW YORK.

TANNlNG PROCESS.

SPECIFICATIQN forming part of Letters Patent No. 300,352, dated June 137, 188%.

Application filedApril in, 1884. (Specimens) To all whom it may concern:

Be it known that I, SAMUEL S. EDDY, a citizen of the United States, residing at Rochester, New York, have invented new and use ful Improvements in Processes for Tanning, of which the following is a specification.

My invention relates to an improvement in the process of tanning, more especially to the tanning of those skins which it is desired to convert into kid-leather. Hitherto in tanning such skins it has been necessary, when taken from the pickle, (or what are known as pickled sheepskins) to extract or kill the pickle, and it has been found that the pro eesses used therefor are apt to injure the skin and detract from the quality of the finished leather.

The object of my invention is to furnish a process by the use of which the tanning may proceed without killing or extracting the pickle which may be in the skin, and to produce economically a high grade of leather, always soft and pliable, and capable of receiving and reliably retaining and holding the color or dye imparted to it. The process by which this is effected is as follows: Suppose the number to be treated is twelve dozen sheep-skins taken from the pickle, (what are known as pickled sheep-skins.) For this number I make a first solution or composition of eighty-four pounds of wheat-bran fermented in one hundred and twenty gallons of water, seventy-five pounds of salt, fifteen pounds of sulphuric acid or oil of vitriol of66 strength, and five pounds of quercitron bark. The bark should be boiled in four or five gallons of water, to extract the strength therefrom before mixing it with the other ingredients.

The composition thus made is intended for white leather. lVhen it is intended to color the leather, it is preferable to add to the composition noted about eightpounds of terrajaponica dissolved in a suitable amount of water.

The in redients of this solution possess qualities peculiarly adapting it for the desired effects on the skins. The wheat-bran tends to soften the skins, while atthe same time it possesses mild tanning properties. The salt is cleansing in its action, as is also the oil of vitriol, while the two, when mixed, form a tanning agent. The quercitron is a well-known tanning agent, giving body or strength to the a horse or rack and allowed to drain for an hour or more, when they are ready for a second solution or composition. This is composed of sixty gallons of water, three pints of soft soap, one pound of glyoeriue, twelve ounces of saleratus, and six ounces of horror. The saleratus and borax should be separately dissolved in alittle water before being added to the other ingredients.

In this composition the use of the soap softens, cleanses, and strengthens the skins, while the glyeerine, in addition to its preservative qualities, tends to keep them soft and pliable. The boran whiten's and bleaches the skins, while it and the saleratus, being alkalies, neutralize any acid remaining in the skins from their treatment in the first solution. In treating the skins in this solution it is preferable to treat a much smaller number at once thanthe twelve dozen for which the entire solution is intended. It is best, therefore, to place about five gallons of this second composition in any suitable tub or receptacle, and place one dozen skins therein, which are then to be handled in the solution for five minutes. This liquor is then to be thrown away and a fresh five gallons used with the next dozen in the same way, and so onuntil all the skins have had a five-minutes handling in this second composition. They are then to be hung up in a hot room until dry. After drying, they are to be seasoned by dipping quickly in water and packing in a box. They should re main so packed for some hoursten or twelve, or, say, over nightafter which the next step is to perch out with the armstake, when they will be ready for the cleansing, which may be done in a solution composed of thirty-six gallons of water, six pounds of alum, and three pounds of salt, in which they should be thoroughly handled for about five minutes. The

skins are now ready for dyeingor coloring and finishing, or for finishing, if white leather is desired. If to be colored, they are colored and worked in the manner usual with kidfinished leather. After a charge of the first solution or composition has been made of the strength and proportions set forth, and used as described, it may serve as a base for the next lot, as it may be strengthened and restored to its original activity by adding to what is left of it fifty pounds of bran fermented as before set out, five to six pounds of sulphuric acid, and twenty-five to thirty pounds of salt, with the necessary quantity of water. The second solution or composition, however, cannot be strengthened and must be made fresh for each lot to be treated, the spent liquor being simply thrown away.

While I have stated what I conceive to be the best proportions of ingredients for the solutions or compositions used, it is of course evident that they may be somewhat varied to meet the conditions of different qualities of I skins.

. operations of washing, draining, and packing,

the final solution acting as an ordinary cleans: ing solution after the changes necessary to forming leather have been completed in the hide, the-pickle in thehides having been neutralized by the conjointefi'ect of the acid and the alkaline tanning solutions.

With these compositions and by this method of treatment I am enabled to proceed with the tanning of pickled skins without first killing or extractingthe pickle,- and to easily and economically produce a strong leather of the highest and best kid finish, soft and pliable, and capable of receiving a good color and durably retaining andholding it. The leather produced is also free from any bad or offensive odor, the effect of the compositions used being to destroy any such odors which might arise from the decomposition or change in the animal fibers.

Having thus described my invention, what I claim is- The improved method of tanning pickled hides, or hides fresh from the'pickle, which consists in first partially tanning by subjecting them in the pickled condition to an acidulating composition substantially of the character set forth, then washing and draining,

and neXt completing the operation of tanning by the action of an alkaline tanning composition substantially of the character set forth, and then drying.

In testimony whereof I affix my signature in presence of two witnesses.

SAMUEL S. EDDY.

Witnesses:

H. H. PYOTT, F. M. EDDY.