A NEW OR IMPROVED PROCESS FOR THE MANU- FACTURE OF ARTIFICIAL LEATHER
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Walter Alfred Barlow at the Office
of the Commissioners of Patents on the 4th November 1882. Commu-
nicated to me from abroad by Emil Pollak of Vienna Austria.
WALTER ALFRED BARLOW of 6 St Paul's Churchyard in the City of London
Patent Agent and Engineer "A NEW OR IMPROVED PROCESS FOR THE MANU-
FACTURE OF ARTIFICIAL LEATHER" A communication to me from abroad by
Emil Pollak of Vienna, Austria.
This invention relates to a new or improved process for the manufacture of
artificial leather which as heretofore produced found but a limited employment as
it could not resist the influence of moisture and when exposed to the wet, would
dissolve into the pieces from which it had been made, for this reason it was never
reliable to be used as sole, heel or welt leather in tho manufacture of bouts
or shoes.
The object of the inventor was, to discover a process, by means of which
artificial leather could be produced which would be impervious to moisture and
insoluble in water.
This object has been attained and is carried out in the following manner :-
To a quantity of water of a temperature suited for easily dissolving starch, a
sufficient quantity of the latter is added to produce a thin solution
To this solution which in a boiling state a small quantity of gum arabic is added
and also about one twentieth part of the former, of a solution of Alum consisting
of five parts (by weight) of water to one part of alum.
Into this mixture after it has cooled leather parings or othe waste pieces of
leather are placed. After having been perfectly saturated they are piece after piece
covered with a concentrated solution of paste and placed in the flat moulds in
layers one on top of the other and beaten with hammers.
The sheets thus formed are placed into a vessel containing a solution of soda-soap
in proportion of about one part (by weight) of soda soap to two parts of water and
after having been well soaked they are brought under the hydraulic press and
pressed.
The following is the chemical process which take place :-
The sulphuric acid leaves its combination with the argillaceous earth in the alum and
combines with the soda of the soap, while C 18 II 36 0 2 stearic acid 3, which in the soap
C 18 H 34 02 oleic acid
were jointly combined with the soda, become free to enter a new combination

page_text: with the argillaceous earth, the bydraulic pressure favouring the most direct
mechanical combination of the two salts.
By this new combination of sebate of alumina, with which the artificial leather
is perfectly impregnated the latter is protected against moisture and becomes
waterproof.
The process just described is for the treatment of parings and pieces of leather
not oiled.
When parings or other waste pieces of oil-dressed leather are to be used, for the
production of this improved artificial leather the process must be somewhat
modified.
The oil dressed parings or pieces are placed into a bath composed of water ninety
fivo parts and five parts of potash or soda waterglass of 35° Beaumé or the
In this bath which
corresponding quantity of waterglass of 50° Beaumé
may be cold or lukewarm the parings are left according to the quantity of fat or
oil they contain from one quarter to one half hour.
The parings having been removed from tho bath and left to drain off are placed
into a solution of sulphate of zinc (proportion about 5-500) and soaked for half an
hour. The parings are now pressed dry and are ready for the manufacture of
my artificial leather.
In place of the water glass any of the alkalis or any of the salts with alkalinous
reaction may be employed and in place of sulphate of zinc any of those salts may
-be used, tho bases of which will form insoluble combinations with acids.
-
The leather pieces or parings thus prepared are now treated the same as those
not oiled. Paste is applied to them and they are placed in layers into moulds and
there beaten.
The sheets thus formed after having been subjected to hydraulic pressure and
--dried are ready for use as artificial leather being waterproof and insoluble.
This:
By the process above described the fat contained in the leather parings or picces
is saponified and the soluble soap transformed into an insoluble one:
renders the removal of the grease from tho parings before their use superfluous and
the fat contained in them is employed for forming the insoluble soap which
renders the leather waterproof.