A New or Improved Material which may be used in Arts and Manufactures in the stead of India-rubber, Gutta-percha, and other similar substances, and Process for Making the same, and for the Utilisation therefor of Waste Liquors from Tanneries.
Year: 1891

page_text: Date of Application, 21st Dec., 1891
Complete Specification Left, 20th Sept., 1892-Accepted, 5th Nov., 1892
PROVISIONAL SPECIFICATION.
A New or Improved Material which may be used in Arts and
Manufactures in the stead of India-rubber, Gutta-percha, and
other similar substances, and Process for Making the same,
and for the Utilisation therefor of Waste Liquors from
Tanneries.
I, WILLIAM RICHARD EARP of Preston Brook, near Warrington, in the County
of Chester, Tanner and Chemical Manufacturer, do hereby declare the nature of
this invention to be as follows:-
It is well known in the chemistry of tanning that the tannic acid acts upon
gelatine and precipitates it or converts it into an insoluble compound, and this fact,
is made use of in the testing of tanning materials to determine the quantity of
tannic acid present.
A compound so formed of gelatine and tannic acid has not been, to our knowledge,
introduced or made use of as an article of manufacture. The object of this
invention is to produce such an article of manufacture as may be applied in the
arts and manufactures for purposes where india-rubber or gutta percha or other
similar substances are now used.
In carrying out the invention, I take a solution of gelatine prepared in a suitable
manner, and to this I add an infusion of any tanning material capable of acting
upon the gelatine in the manner above described. The infusion is added to the
solution until all the gelatine is precipitated as an insoluble compound. The
gelatine is filtered off or decanted, and the remaining liquid is run off.
The gelatinous mass is then worked or kneaded until it is of the consistency
required. When thus prepared, it somewhat resembles, in appearance, pure gutta
percha or caoutchouc. It may be softened by the application of heat, so as to be
readily manipulated or worked for the purposes for which it is required.
I also carry out this invention for the utilisation of the waste tanning liquors
from tanneries, and, for this purpose, I make a solution of gelatine from the
Heshings of hides or from the glue pieces or horns or other suitable body, and
conduct, into this solution, the waste tanning liquors as they run from tanneries (or,
if preferred, it may be previously concentrated) until the whole of the gelatine in
solution is precipitated, or the mixture somewhat supersaturated with the old tan
liquor. The precipitate I then filter off or decant, and run the filtrate away. I
then work up the precipitate in manner as before stated.
Dated this 19th day of December 1891.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
COMPLETE SPECIFICATION.
New or Improved Material which may be used in Arts and
Manufactures in the stead of India-rubber, Gutta-percha, and
other similar substances, and Process for Making the same.
and for the Utilisation therefor of Waste Liquors from
Tanneries.
1, WILLIAM RICHARD EARP, of Preston Brook, near Warrington in the County
f Chester, Tanner and Chemical Manufacturer, do hereby declare the nature of
his invention and in what manner the same is to be performed, to be particularly
escribed and ascertained in and by the following statement:-
It is well known in the chemistry of tanning that the tannic acid acts upon

page_text: gelatine and precipitates it or converts it into an insoluble compound, and this
fact is made use of in the testing of tanning materials to determine the quantity of
tannic acid present.
A compound so formed of gelatine and tannic acid has not been to my knowledge
introduced or made use of as an article of manufacture. The object of this
invention is to produce such an article of manufacture as may be applied in the
arts and manufactures for purposes where india-rubber or gutta-percha or other
similar substances are now used.
In carrying out this invention, I take a solution of gelatine prepared in any
suitable manner such as dissolving gelatine in water and to this I add an infusion
of any tanning material, such as barks and woods of different kinds,-myrobalan,
divi divi, valonia or other woods, barks, berries, leaves, pods, or roots of such
bolics as yield tannic acid. The infusion of the tanning material is added until
all the gelatine is precipitated as an insoluble compound. The insoluble precipitate
is then decanted or filtered off and the filtrate or remaining liquor is run away.
The precipitate is then worked or kneaded (with the addition of a further quantity
of gelatine) until it is of the consistency required. Various articles may be added
to this gelatinous precipitate to give it the necessary hardness, softness, or
elasticity, such as linseed oil for producing softness and elasticity, ground glass.
silica, clays or earths or other bodies in an impalpable powder for producing
hardness. When thus prepared it resembles in appearance gutta-percha or
caoutchouc and it may be softened by the application of heat or by holding and
kneading under warm water, so as to be readily manipulated or worked for the
purposes for which it may be required.
In some cases instead of making a solution of gelatine and adding a solution of
tannin to it until all the gelatine is precipitated as described, I take a solution of
tannin and add excess of gelatine to it, that is until all the tannin is precipitated,
and afterwards, in some cases, add as much excess of gelatine as is required to
bring the precipitate to the desired composition.
I also carry out this invention for the utilisation of the waste liquors usually
found running from tanneries and for this purpose I make a solution of gelatine
from the fleshings of hides or from the glue pieces, horus or other suitable body
and conduct into this solution the waste liquors as they run from tanneries, (or if
preferied they may be previously concentrated) until the whole of the gelatine in
solution is precipitated or the mixture somewhat supersaturated with old tan liquor.
The precipitate I then filter off or decant and run the filtrate away, I then work
up the precipitate in manner as before stated.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
1. The manufacture, and use as a substitute for india-rubber, gutta-percha or
kindred composition, of a compound of gelatine and tannin, substantially as
described.
2. The recovery and utilisation of the tannin from the waste tanning liquors of
tanneries by precipitating the same by means of gelatine, and the manufacture
from the precipitate of useful composition, substantially as described.
Dated this 19th day of September 1892.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham, and London, Patent Agents.