A New or Improved Process for Tanning all kinds of Hides or Skins.
Year: 1891

page_text: Date of Application, 21st Feb., 1891
Complete Specification Left, 21st Nov., 1891-Accepted, 24th Dec., 1891
PROVISIONAL SPECIFICATION.
A New or Improved Process for Tanning all kinds of Hides
or Skins.
1, WILLIAM BOLT, of 49 Greendyke Street, Glasgow, in the County of Lanark,
North Britain, Tanner, do hereby declare the nature of this invention to be as
follows
This invention which relates to an improved process for tanning all kinds of
hides or skins, consists as follows:-
I first dissolve catechu or any other extract of tanning or tanning material.
i next make a solution of chloride of sodium or sulphate of magnesium or both
together to stand in strength from 5 to 12 Twaddell I then mix the two together at
a strength of 7 to 14 Twaddell and boil the two together for from 10 minutes to
1 hour.
I
When at hand heat I put the goods in this and well handle up and down.
keep the goods in this from 3 to 24 hours, according to the thickness of the hides
or skins or until the tanning is through them or they have scoured, from 2 to
4 degrees Twaddell. I then take out, let drain, if for curing, cure in the usual way,
if for tanning, put forward into strong liquors, the strength of the bath may be more
or less, or I may cure first and use the bath after.
Duted this 20th day of February 1891
JOHNSONS,
115, St. Vincent Street, Glasgow, Petitioner's Agents.
A New or Improved Process for Tanning all kinds of Hides
or Skins.
I, WILLIAM BOLT of 49 Greendyke Street Glasgow, in the County of Lanark,
North Britain, Tanner, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
This invention which relates to an improved process for tanning all kinds of hides
or skins, consists as follows:
:-
lime or any of the known
skins cleaned in the usual
pured" "drenched' or
The hides or skins are prepared in the usual way with
processes; the hair and flesh removed, and the hides or
way; if for dressing purposes they are "baited,"
"chemiced"; they are now ready for tanning which I commence as follows:-
I make a decoction of catechu or any other tanning material at any given
strength. I next make a solution of chloride of sodium or sulphate of magnesia
or of them both together in equal proportions taking care to make solution enough
for the immersion of the hides or skins that are going to be tanned at a strength
of 5 to 12 Twaddell. I now add enough tanning material to the salt's solution to
increase the strength 2 degrees Twaddell. I now boil the two together from
10 minutes to 1 hour according to the tanning used. When cooled down to hand
heat I put the hides or skins into this and well handle in and out. I keep in this
from 3 to 24 hours or longer according to the strength of the bath or the thickness
of the hides or skins, or till the colour of the tanning is through them, or until they
have got scoured that is, cleaned thoroughly of all animal matter and of all the
ingredients left in the hides or skins from the preparation which will cause the glass
to rise from 2 to 4 Twaddell. I now take out, and let drain.

page_text: The bath having thoroughly cleaned the hides or skins of all useless matters and
at the same time the tanning in the bath has protected and preserved all the
valuable portions of the hides or skins, they are now ready to be finished tanning
by any of the usual processes either curing with the mineral tannages or put
forward into strong vegetable tanning liquors and repeatedly fed until the tanning
is completed.
In some cases 1 partly cure or tan first especially when the goods have been
overprepared.
The bath may be used weaker or stronger than here stated or the composition
may be modified by adding more tanning material than stated especially if the
scouring is too severe which is seen by the grain of the hides or skins drawing as
some tannages suffer partial decomposition by boiling, such as oak bark etc. I prepare
my bath without boiling with these tannages.
I sometimes alter the colour of the tans by adding a dye material to the bath.
By the use of my invention the hides or skins are tanned in one third the usual
time and the tanning liquors used are about one half the strength of the usual
tanning liquors, the leathers are superior for all purposes and the weights of the
finished articles exceed those done by other processes.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed declare that what
I claim is :-
1st. The improved process for tanning all kinds of hides or skins substantially in
the manner as hereinbefore described.
2nd. In the tanning of all kinds of hides and skins the use of sulphate of mag-
nesium and chloride of sodium either mixed together or separately, substantially in
the manner as hereinbefore described.
Dated this 12th day of November 1891.
JOHNSONS,
115, St. Vincent Street, Glasgow, Applicant's Agents.