Improvements in or relating to the Treatment of Hides for the Manufacture of Leather.
Year: 1894

page_text: Date of Application, 27th Nov., 1894
Complete Specification Left, 22nd Aug,, 1895-Accepted, 5th Oct., 1895
PROVISIONAL SPECIFICATION.
Improvements in or relating to the Treatment of Hides for the
Manufacture of Leather.
I, WILLIAM RICHARD EARP of Preston Brook, near Warrington in the
County of Chester, Borax Manufacturer and Tanner do hereby declare the
nature of this invention to be as follows:-
It is well known by tanners that in softening dry liides which come to this country,
there is great difficulty in preventing putrefaction going on whilst they are soaking
in order to get them into a proper state for depilating, and that this putrefaction
goes on to such a great extent in a great many cases, that before the hides can
be got properly soft, most of them are much wasted, and some of them entirely
rotten and useless.
This invention has for its object the entire prevention of putrefaction whatever
in hides, so that if the hide be sound when the tanner gets it, he may rest assured
that it will be sound after the process of softening, no matter how long the hides
may have been in soak.
In carrying my invention into effect, I soften the hides so as to get them into
proper condition for depilating and tanning, and utilise the waste mother liquor
from borax manufacture for preventing the putrefaction or waste of the hides
whilst undergoing the process of soaking and cleansing prior to their being tanned.
In the manufacture of borax when the mother liquor becomes so treated with
other compounds of soda that it becomes impracticable to grow further borax
crystals from them, this mother liquor is practically useless to the borax manu-
facturer, but from experiments which I have made I find that it possesses
remarkable properties for preventing the putrefaction of hides when in a moist
state or in a water soak. This waste liquor I utilise for the purpose named..
The following is the procedure :-
I make a soak of water and put into it as much waste borax liquor as will
bring the specific gravity to 1035-1050 that is 7° to 10° Twaddle.
I then place
the hides therein and let them remain till they are sufficiently soft, handling them
several times during the period, or if drums are used, I make the soak of the
stronger specific gravity, and tumble them until they are sufficiently soft, when
they can be washed once in clean water and they are ready for the depilating
process. For tainted hides of any cure, I put sufficient of the waste borax liquor
into the water soak to bring the specific gravity up to 1015-1020 that is 3°
to 4° Twaddle.
The advantages gained by this process are very great, as in addition to the
entire prevention of putrefaction, the borax liquor has great cleansing properties,
and the hides are a better colour all through the tannage than those that have
not been so treated, so that the advantages may be summed up as follows:-
:-
1. Entire prevention of loss of bide substance and consequently greater weight
of leather;
2. Better coloured grain and cleaner an1 brighter leather throughout.
Dated this 26th dow of Narambon 1001
WM. P. THOMPSON & Co.,
Of 6 Lord Street, Liverpool, Patent Agents for the Applicant.

page_text: COMPLETE
SPECIFICATION.
Improvements in or relating to the Treatment of Hides for the
Manufacture of Leather.
I, WILLIAM RICHARD EARP of Preston Brook near Warrington in the
County of Chester, Borax Manufacturer and 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 :-
It is well known by tanners that in softening dry hides which come to this
country, there is great difficulty in preventing putrefaction or decomposition going
on whilst they are soaking in order to get them into proper state for depilating,
and that this putrefaction goes on to such a great extent in many cases, that before
the hides get properly soft they are much wasted, and some are entirely rotten and
useless.
This invention has for its object the absolute prevention of putrefaction in hides
whilst they are being soaked for the purpose of softening them, so that if the hide
be sound when the tanner gets it he may rest assured that it will be equally sound
after the process of softening, no matter how long the hides may have been
in soak.
In carrying my invention into effect, I soften the hides, so as to get them into
proper condition for depilating and tanning, by utilising for the softening soak the
waste mother liquors from borax manufacturing. In the manufacture of borax
when the mother liquors become so saturated with other compounds of soda that
it becomes impracticable to grow further borax crystals from them, this mother
liquor is practically useless to the borax manufacturer. I find however that this
liquor possesses remarkable properties for preventing putrefaction of hides, when
in the moist state or in a water soak.
In carrying out the operation, I make a soak of water and put into it as much
waste borax liquor as will bring the specific gravity to about 1.035 to 1.050, that
is 7 to 10 Twaddle. I then place the hides therein and let them remain till they
are sufficiently soft, handling them several times during the period, or if drums are
uscd make the soak of the strongest specific gravity above mentioned and tumble
them until they are sufficiently soft, when they can be washed once in clean water
and they are ready for the depilating process. For hides of every kind, which
may not require softening whether cured or fresh market hides, I put sufficient
of the waste borax liquor into the water soak to bring the specific gravity up
to 1015 to 1.020, that is 3 to 4 Twaddle. In speaking of the waste mother liquor
of borax manufacture, I mean more especially the waste liquor of the process
generally carried on in this country. This liquor has usually from 5 to 10 per cent.
of borax left in it, and in addition to this has 5 to 10 per cent. of carbonate of soda,
15 to 20 per cent. of common salt, and 5 to 10 per cent. of sulphate of soda. I do
not however limit myself to a solution of these materials. The useful ingredient is
the borax, and other waste liquors containing borax (without deleterious ingredients,
such for instance as free sulphuric acid or a very acid salt, or a large amount of
free alkali) could be used equally well. Besides the borax too, the carbonate of
soda has a purifying action and the common salt has an antiseptic and preservative
action. The liquor is thus very valuable for the purpose. The advantages gained
by this process are very great as in addition to the prevention of putrefaction by
means of the borax more especially contained in the compound, the liquor has
great cleansing properties and the hides treated in this manner have a better colour
all through the tannage than those treated in the usual manner.
The advantages may therefore be summed up as follows
Firstly practically the entire prevention of loss of hide substance and conse-
quently greater weight of leather produced.

page_text: Secondly, better coloured grain and cleaner and brighter leather throughout, and
Thirdly, increased strength and durability owing to the absence of the before
mentioned putrefaction.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
1. The improvement relating to the treatment of hides for the manufacture
of leather, which consists in the utilisation of the mother liquor of borax works
for a soak diluted to the requisite strength, substantially as herein described.
2. The improvement in the treatment of hides for the manufacture of leather,
which consists in soaking them in a waste solution containing borax and cleansing
salts without other substances which would be injurious to the hide in sufficient
quantity to hurt the same, substantially as described.
Dated this 21st day of August 1895.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Birmingham, and London, Patent Agents.