US945221A - Method of removing hair from hides. - Google Patents

Description

" UNITED stm' rns PATENT oFFIoE.

LEWIS cn'nnssmm, os'scnanron, rnnnsnvmm.

mnrnon or REMOVING HAIR mom moss.

The object of my invention is the provision of an improved method of removing hair from hides preparatory to tanning the same,

which method shall effect a saving in time and reduce the cost as compared with common methods now in use for a similar purpose.

I have ascertained that the animal fat acids at the base of the hair in a hide will be saponified by the action of hydrated oxid of barium forming salts miscible in water. The reaction effectively loosens the hair so that it will fall out or be easily removable.

To commercially and .thus ractically employ the hydrated oxid of ariu'm for removing the hair from hides I have devised two specific methods. In carrying out the first specific method a bath is formed by adding barium sulfid to Water. In'the bath the barium sulfid is at once decomposed, forming a solution of hydrated oxid of barium and barium sulf-hydrate. To convert the barium sulf-hydrate into the hydrated oxid of barium, and so make available all the barium without any waste, sufficient lime, referably in the form. of milk of lime, is ad ed to the bath, thus converting the sulf-hydrate into the hydrated oxid of barium.

The reaction upon the addition of the lime is as follows:

a( 2+ 2 2+ (Gas)? "the sulf-hydrate of barium into hydrated Specification of Letters lfatent. Application flled September '16, 1907. Serial No. 393,210.

Patented Jan. 4, 1910.

oxid of barium. The amount will, of course, depend upon the size of the bath. To determine when sufficient lime has been added, fr0m t1me to time a small quantity of the solution may be removed from the bath and treated in a small vessel with lime, and when this reagent fails to throw down a preci itate of sulfid of calcium suflicient l1me as been added to effect the conversion of the sulf-hydrate of barium into the h drated oxid. The quantity of lime to e added may also be determlned experimentally byl observing the effect of the solution upon t e hides therein. When the hair fails to loosen obviously the hydrated oxid of barium has become exhauted or exists only in a small amount, and lime should be added until sufficient barium sulf-hydrate is converted into the hydrated oxid to loosen the hair. When the further attention of lime is not accompanied with the loosening of the hair the barium in the bath has become exhausted and a new bath is necessary.

The sulfid of barium may be produced by grinding the sulfate of barium to a fine owder, mixing it with fine coal, and roast- 1n the mixture in a furnace, reducing the su fate to sulfid.

The hides, whether green or salted or cured, are preferably soaked in water to soften them and toremove all dirt and chemicals, and then they are immersed in the bath and allowed to remain until the hydrated oxid of barium has acted upon the fat acids at the follicles or base of the hair and decomposed the same. The hides are then withdrawn from the bath and the moved in any convenient way. In some cases the hides prepared for the bath may be immersed in the primary solution containin the hydrated oxid of barium and the su f-hydrate of barium, and when the hydrated oxid has become exhausted the lime or milk of lime be added to convert the sulf-hydrate into the hydrated oxid of barium.

In carrying out the second specific method a thorough mixture is formed of lime preferably as hydrated oxid of water slaked lime, barium sulfid, some inert finely ground material, such as sandstone, and a quantity of water sufiicient to make a paste or comosition of creamy consistency. Seventy our parts of hydrated oxid of lime, one hundred and sixty nine parts of barium depilation is effected.

sulfid, and a suflicient quantity of the powdered material and water to will in practice constitute a desirable composition for the'purpose intended.

The chemical reactions in the mixture are as follows:

The hides having been cleaned and all chemicals removed, as in the first specific method, the paste is applied with a brush or otherwise to the fleshy side of the hides where it is allowed to remain until the The action of the hydrated oxid of barium upon the fatty acids present at the roots of the hair is the same as hereinbefore specified.

From the foregoing description of the two specific methods of procedure it becomes clear that all the barium in the sulfid of barium is made available as hydrated oxid,

and consequently great economy is attained which makes the method commercially successful. a

Itis well known that barium sulf-hydrate can be converted into barium hydrate by. the

action of calcium hydrate, but it remained for me to discover that a bath or paste for removing hair from hides and skins could be produced which would not disintegrate or destroy to an injurious degree the hair or hides present, thus obviating the difficulties met with in the prior art, by exposing the hides and skins to the action of a depilating bath or paste free to an injurious extent from actlve sulfur containing compounds of alkali or alkali earth metals, and that substantially all sulfur fromcompositions initially containing such sulfur containing compounds, as barium sulf-hydrate soluble or in solution could be rendered inert in the bath or paste by subjecting them to the action of calcium hydrate or substances forming the same, such as lime and water, substantially all of the sulfur into calcium sulfid, with calcium sulfid is practically insoluble in solutions of alkaline nature containing traces of calcium hydrate or more.- Superior results are obtained in employing the desulfurized depilators as before described and as revealed and claimed in the form a paste' in sufiicient quantity to convert 5 present application, in that barium hydrate .free from sulfur containing compounds in an active state readily combines with and saponifies the fatty acid esters or salts surrounding the follicle of the hair, andconverts the same into a miscible condition admitting of the ready removal or dislodge ment of said hair, and without destroying the hair or the skin or hide to which the compositionis applied for depilating purposes. By. this procedure the saponifying action of the barium disclosed by the pr or art, and which facts distinguish and differentiate my invention therefromparticular attention being called to the fact that my depilating solution or pastecontains no sulfur in an active state, the compositions of which retard the action and destroy the hair and .skinin the prior art, the whole of the sulfur'being rendered inert in the bath or paste in my method. What I claim is:

1..The method of removing hair from hides consisting in treating the same with a composition barium hydrate, the quantity of sufficient only to the sulf-hydrate oxid of barium.-

2. The method of removing hair from hides consisting in forming a composition containing sulfid of barium, adding thereto calcium oxid and water in proportions suflicient only to precipitate substantially all the sulfur therefrom, and thereafter subj ecting the hides to the action of the residual compound.

3. The method of removing hair from hides consisting in forming a composition containing sulfid of barium and inert material, adding thereto calcium oxid and water in proportions sufficient only to precipitate substantially alljthe sulfur therefrom, and thereafter subjecting the hides to the action of the residual com ound.

In testimony whereof I a 2: my signature inpresence of two witnesses.

LEWIS CHEESEMAN.

calcium oxid and water;

Vitnesses:

CHAS. H. WELLES, Jr., CHAS. D. SANDERSON.

hydrate is not retarded nor the hair destroyed, as in compositions of barium sulfhydrate,

calcium hydroxid being