IMPROVEMENTS IN THE MANUFACTURE OF LEATHER FROM CLIPPINGS AND WASTE PIECES OF SO CALLED PATENT LEATHER AND OTHER LEATHER
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Edward Griffith Brower at the
Office of the Commissioners of Patents on the 20th June 1882. Communi-
cated to him from abroad by Abraham Levy of Paris France.
EDWARD GRIFFITH BREWER of 33 Chancery Lane in the County of Middlesex
IMPROVEMENTS IN THE MANUFACTURE OF LEATHER FROM CLIPPINGS AND WASTE
PIECES OF SO CALLED PATENT LEATHER AND OTHER LEATHER"
cation to me from abroad by Abraham Lovy of Paris France)
(A communi-
The object of this invention is an improved method for manufacturing leather
more particularly suitable for boot and shoe manufacture but equally applicable
to other purposes where leather is employed. For this purpose clippings and
waste pieces of varnished leather (the so called patent leather for example)
which hitherto has not been utilized except as a manure and a fuel; the varnish
which covers one of the surfaces preventing adherence between the different layers
which it may be desired to place one on the other.
This important result has been attained by first submitting the clippings and
waste of this varnished leather to an operation the object of which is to render
the leather supple or soft, to alter the nature of the varnish which covers them
and to completely impregnate them with a gum or adhesive substance to be
employed to connect thein together; the operations of coupling and compressing
the different pieces of leather is effected in the ordinary inanner.
According to this invention the clippings of varnished leather to be utilized
are placed in a suitable vessel but preferably in a mixer known in France as a
"turbulent" and formed of a cube turning on one of its diagonals In this kind
of vessel the leather is brought into contact with skin gum or size to which about
25% to 30% of its weight of water is added; this skin gum or size, which
is that made use of by painters for buildings in the painting called sizing, may
be replaced by gelatine or glue if preferred, under any circumstances the
operation takes place at a temperature varying from 86 to 104° Fahrenheit so as to
facilitate the penetration of the gum into the clippings without however the
temperature being such as to alter the leather. The duration of this softening
operation is about two hours and after the operation the leather is very supple
and impregnated with gum, in fact 200 lbs of leather cuttings absorb 160 lbs of

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size and the proportionate quantity of water in which it was dissolved (it has been
before indicated that this gum was dissolved in 25 to 30% of water. When
removed from the vessel the pieces or cuttings of leather are placed on a table in
a metal frame so as to cross them more or less according to the thickness of the
leather and that desired to be given to the sheet; this operation is effected in the
manner usually adopted for the manufacture of ordinary superposed leathers which
will now be successively described.
On a sheet of zinc some fabric preferably a woollen fabric is placed on which
a thin layer of the parings or scrapings of leather of good quality that has been
impregnated with some gum; on this layer are placed, with care the clippings of
varnished leather impregnated with size of the kind before referred to and there
is thus formed a thickness in proportion to that of the sheet of leather to be
produced; a thin layer is added of the parings similar to the others which is
covered with a fabric and then with a sheet of zinc. The whole is then submitted
to the action of a powerful hydraulic press which has the effect of consolidating
the cohesion of the gummed pieces-and to express from it any excess it may
contain. The compressed sheets are afterwards dried in the air or in any other
convenient way then submitted to pressure afresh either by means of a bydraulic
press or otherwise or in a rolling mill; they are then ready for the market.
By the above means sheets of leather can be manufactured the dimensions of
which are only limited by that of the size of the presses at command.
The artificial leather thus produced suits perfectly for the manufacture of heels
or soles for boots and shoes they are besides applicable to a great number of
purposes to which leather is now applied.
Although the invention has been described with reference specially to the
manufacture from clippings or waste pieces of varnished leather it is to be under-
stood that the process is applicable to the utilization of the clippings or waste
pieces of all sorts of leather being mixed in suitable proportions with the clippings
of varnished leather.