US328978A - Geoege p - Google Patents

Description

.lUNrrsn Stratus PATENT riuca GEORGE Fl SCHXVEITZER, ()F LINCOLN, NEBRASKA.

PROCESS OF TANNBNG.

SPECIFTCATEQN forming part of Letters Patent No. 328,978, dated October 27, 1885.

Serial No. 157,365. (No specimens.)

To (tZZ whom it may concern.-

Be it known that I, GEORGE F. SoHwEIrzER, a citizen of the United States, residing at Lincoln, in the county of Lancaster and State of Nebraska,haveinveuted certain new and useful Improvements in the Process of Tanning; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use the same.

Heretofore in tanning hides by the method called mineral process, the hides were soaked for a short time, commonly, in impure water, and thereafter all hides,without regard to their various qualities, were limed for a certain equal and definite time, and were then placed in a brine of watcrand salt only, being thereafter removed and exposed for some time to the smoke from a comparatively large quantity olsulphur, and subsequently tanned in a liquor containing salt, alum, and extract of hemlock-bark, with the occasional addition of japan-earth. This method is crude and very unsatisfactory in its effect on the leather, both as to quality as well as appearance. By the old process of tanning with bark,three months time at least was required to completely tan the hide, while by the newer mineral process the tanning can be accomplished in from three to six days,and by my improvements leather is produced much tougher and more durable than has heretofore been secured, as well as at a much less expense, than formerly.

The method I pursue and the compositions I use are as follows: The hides are first soaked from one and a half to two days in pure fresh water to thoroughly cleanse them from blood and all extraneous matter, thereby preparing them to readily and quickly absorb the lime to be applied to them. The hides are then limed, according to their sort or kind, for from six to ninevdays, and the hair removed. Ilarness-lcather, for instance, does not require so much liming to make it strong and tough as whip or net leather does. I then clean the hides and place them in saltwater in which five pounds of alum has been dissolved, in which I allow the hides to remain at least two days. The alum in this brine accomplishes a slight tanning effect on the hides, which I think desirable, before they are submitted to the next process, which is to remove them from the brine and hang them up in a box,

where they are submitted to the fumes of sulphur. In this process care must be exercised to not submit the hides to the sulphur-smoke too long. Hides intended for boot and shoe leather should remain in the smoke of four pounds of sulphur about twelve hours; for whip and net leather, in smoke of six pounds of sulphur for eighteen to twenty hours, while thick hides forsaddle and harness leather may remain in the fumes of eight pounds of sulphur for twenty-four hours. The hides are then placed in a liquor containing in solution Salt, alum, and extract of either hemlock or catechu, and sulphuric or muriatic acid.

For hides suitable for belt orharness leather, I use catechu instead of hemlock, as being stronger, and sulphuric rather than muriatic acid, adding about onehalf a gallon of the sulphuric acid. The liquor should be made weak at first and gradually made stronger, and for this quality of hides should contain more alum than salt; but for hides to be made into fine bleached or aniline-colored leather, use alum and salt in equal quantities, and use sumac instead of hemlock or catechu. The sulphuric acid should be put in a little atfirst, and gradually increased in amount until all is used.

Forhides suitable for boot and shoe and net leather, more salt than alum should be put into the liquor, and extract of hemlock or chestnut used instead of catcchu, and instead of sulphuric acid use one-half gallon of muriatic acid.

Great care should be exercised to not make the liquor too strong at first; but all the material should be added to theliquor gradually.

The hides should be turned at least three times every day, andif all is properly done the hides will be thoroughly tanned in from three to six days. Next remove the hides from the liquor,and scour them slightly,and hang them up in a warm room until wind'dried. Then take them down, moistening the parts (if any) that have become quite dry,and fold and pack them carefully, and, so far as possible, in such by hand with a preparation made of fivemanner that the drier parts will be upon the wet .or moist parts. Let them remain folded and packed one day. Afterward stuff them with degras, tallow, and fish-oil mixed with some yellow wax. For .harness'leather use more t-allow than degras and fish-oil, and for whip and net leather use more degras and fish-oil than tallow. After drying I set out the hides twice and then finish up as usual.

In the foregoing description, the quantities of material named have been such amount as is used in the process for forty hides.

In the process for bleaching the hides for fine and aniline-colored leather I usetwo baths,

which for twenty hides are made as follows: Five pounds of sugar of lead are put into sixteen gallons .of pure warm water, and one quart of sulphuric acid isput into ten gallons of pure water, the two baths being of course prepared in separate vessels. The hides are first drawn through the solution of sulphuric acid to cleanse them, and they are then drawn three times through the solution of sugar of lead. After scouring slightly, I stuff them parts cod oil and one part of tallow. They are then dried in a warm room and afterward set out a first time, then dried againand set out a second time, and when dry I prime them with red Brazil wood and apply the aniline color desired; but I preferably use yellow or red on this ground-priming.

What I claim as new, and desire to secure by Letters Patent, is-

1; The method of treating hides, consisting of, first, thoroughlycleansing them in pure fresh water; second, liming them to remove the hair; third, submerging them in a bath of water containing salt and alum in solution; fourth, submitting them to the fumes of sulphur; fifth, tanning them in a liquor having in solution salt,-alurn, sulphuric acid, and the extract of bark; sixth, bleaching in a bath containing sulphuric acid in solution, and, seventh, bleaching in a bath containing sugar of lead in solution, all in successive order, and

substantially as described.

2. In tanning hides, the following process: first, cleansing them by soaking in pure water from one to two days; second, liming them from six to nine days for removing the hair; third, submerging them in water having salt and alum in solution for two or more days; fourth, exposing themto the smoke of sulphur from twelve totwenty-four hours, and, fifth, curing them in a liquor containing in solution salt, alum, sulphuric acid, and the extract of a tanning-bark for from three to six days, the liquor to be made weak at first and gradually stronger, all substantially as described.

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

GEORGE FL SCHWEITZEB.

Witnesses H. FRINOKE, M. FRINOKE.