AN IMPROVED PROCESS AND COMPOSITIONS FOR TREATING HIDES OR LEATHER, TO RENDER THE SAME IMPERMEABLE
Year: 1879

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"AN IMPROVED PROCESS AND COMPOSITIONS FOR TREATING HIDES OR
LEATHER, TO RENDER THE SAME IMPERMEABLE." A communication from
abroad by Henri Trenk, of Bucharest, Roumania,
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 27th March 1879.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "AN IMPROVED PROCESS AND COMPOSITIONS
FOR TREATING HIDES OR LEATHER, TO RENDER THE SAME IMPERMEABLE.
communication from abroad by Henri Trenk, of Bucharest, Roumania.]
[A
The Invention relates to an improved process and compositions for treating hides
or leather to render the same impermeable, and consists partly in impregnating the
same with a solution of glue, to which is added a salt capable of causing the
coagulated glue which impregnates the pores to be insoluble in water.
The baths which I prefer to employ are composed of the undermentioned
ingredients, the proportions of which may be varied as follows, that is to say,—
1200 grammes
First. Water
Glue
Bichromate of potash
Second. Water
Glue
-
Bichromate of potash
-
15
ditto
5
ditto
1500 grammes
50 do.
30
do.
The temperature varies from 10° to 100° according to the composition of the
bath; a bath which is charged with only a small portion of bichromate of potash is
employed cold, in which case the hide, skin, or the like should be soaked in it for
twenty four hours. The bath is kept at a temperature which is to be increased
when the proportion of glue and bichromate is large and according to such pro-
portion; and when hot and strongly charged baths are used, the hides are simply

page_text: If the skins or hides are not very supple or flexible, I add to the bath of glue
and bichromate from 25 to 50% of whale oil, or the hides may be greased previous
to their being placed in the bath, the latter operation being preferable.
The bichromate of potash may be replaced by any other salt which will render
the coagulated glue insoluble, for example, I may employ a mixture of acetate of
lead and of alum in the following proportions, that is to say,—
Water
1000 grammes

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 27th
September 1879.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "AN IMPROVED PROCESS AND COMPOSITIONS
FOR TREATING HIDES OR LEATHER, TO RENDER THE SAME IMPERMEABLE." A
communication from abroad by Henri Trenk, of Bucharest, Roumania.
This Invention relates to an improved process and compositions for rendering
hides or leather impermeable, and consists partly in impregnating the same with a
solution of glue, to which is added a salt having the property of rendering the
coagulated glue that fills the pores insoluble in water.
I prefer to employ baths composed of the undermentioned ingredients, the
proportions of which may be varied as follows, that is to say,-
First. Water, 1200 grammes; glue, 15 grammes; bichromate of potash, 5
grammes.
Second. Water, 1500 grammes; glue, 50 grammes; bichromate of potash, 30
grammes.
The temperature varies from 10° to 100° centigrade, according to the composition
of the bath; a bath which is charged with only a small portion of bichromate of
potash is employed cold, in which case the hide, skin, or leather should be soaked
in it for twenty four hours.
The bath is kept at a temperature more or less elevated, according to the
proportion of glue and bichromate; when strongly charged, hot baths are used; the
hides or skins are simply passed through them, and are immediately taken away
to dry.
If the hides or skins are not very supple on flexible, I add to the bath of glue
and bichromate, from 25% to 50% of whale oil; or the hides may be greased
previous to their being placed in the bath, the latter treatment being preferable.
The bichromate of potash may be replaced by any other salt which will render
the coagulated glue insoluble, for example, I may employ a mixture containing
acetate of lead and alun in the following proportions, that is to say,—
Water, 1000 grammes; glue, 10 grammes; alum, 100 grammes; acetate of lead,
100 grammes.
In all cases the hides leaving the glue bath are dried, then coated on both sides
or on one side only, that is to say, either on the flesh side or on the hair sido as
desired with pure paraffine, or with paraffine mixed with fatty matter, if the skins
should still require to be greased, for example, I may employ a composition of
paraffine, 50 parts; whale oil, 50 parts; liquid pitch, 15 parts.
°
The paraffine is mixed in the proportion of from 2 to 4% with petroleum; it
may be replaced by liquid pitch.
If the leather is for boots which are to be worn with the flesh side of the hide on
the outside, this side or face of the leather will be coated in order to render it more
impermeable with a composition, the basis of which is tar, such as resin, 100 parts;
tar, 300 parts; whale oil, 200 parts; or resin, 50 parts; tar, 50 parts; essence of
turpentine, 50 to 75 parts.
When tar is employed, it is preferable to coat or smear the hides with it before
immersing them in the bath. Hides thus treated are completely impermeable on
both sides. The glue and salts contained in the pores of the leather and hides are
changed into a soft and flexible mass which is insoluble in water in contact with
resin and fatty matter.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,-
First. The employment of a solution of glue, to which is added a salt having the

page_text: property of rendering the coagulated glue insoluble in water, as above set forth and
for the purpose specified.
Second. The treatment of hides or skins on one or both sides or faces with tar,
paraffine, resin and oil which transform the glue and salts into a substance soft and
flexible and in soluble in water, as above set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twenty seventh day of September, in the year of our
Lord One thousand eight hundred and seventy nine.
WILLIAM KOB'. LAKE. (L.B.)