Improvements in or relating to the Treatment of Leather Waste and in Apparatus Employed therein.
Year: 1897

page_text: Date of Application, 19th Oct., 1897-Accepted, 27th Nov., 1897
Improvements in or relating to the Treatment of Leather Waste and
in Apparatus Employed therein.
A communication. from GASTON BRIGALANT of Barentin (Seine Inferieure)
Republic of France, Manufacturer.
I, ALFRED JULIUS BOULT of 111 Hatton Garden in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
Leather is in its ordinary state fibrous, but these fibres cannot be laid bare
either chemically or mechanically. The fibres of leather are lost or embedded in its
adhesive substance and it would not be easy to separate them from it.
This invention relates to a process for preparing leather waste by soaking,
washing, stretching, fulling and converting it into pulp, which is termed
Fibroleum, and to apparatus employed therein.
By means of this process the texture of leather is completely transformed: the
leather is softened and treated so that the adhesive substances surrounding the
natural fibres are stretched into artificial fibres, then reduced to a pulp, this
latter being mixed or not with a certain quantity of textile fibres without any
addition of glue. In order however, to make the pulp water-proof, aluminated
colophonium (rosin) may be added to it, then the pulp is subjected to a series of
well-known operations in order to transform it into sheets of different thicknesses
and of any desired dimensions.
The accompanying drawing illustrates, by way of example, an apparatus for
attaining the desired result. After soaking the leather waste in hot water in
macerating vats for about 15 days, the waste is subjected in the apparatus shown
to the operations of washing, stretching, fulling and reduction to pulp.
In a cast-iron vat A are arranged two superposed steel-rollers with teeth
engaging with each other, but so as to leave a certain amount of clearance. The
edges of the teeth of the upper roller are rounded while those of the teeth of the
lower one are sharp. These two rollers are driven. by toothed wheels arranged
outside the vat so that the relative position of teeth always remains the same. The
leather waste is delivered to the rollers along a central wall, or table D, and thence
passes into the lower portion of the vat and is raised by a pump E into a compart-
ment into which dips a drum G covered with metallic netting or perforated
material. In this compartment the washing of the material takes place. The
dirty water passes through the metallic sieve or netting and is discharged through
a central opening H while fresh water is introduced into the chamber F and re-
places the water discharged.
In passing in the spaces between the teeth of the rollers B and C the pieces of
leather are not cut but simply stretched, fulled and compressed. This opera-
tion is continued for from six to twelve hours or more, according to the degree
of hardness and nature of the leather treated. The leather waste in its passage
between the teeth of the rollers is simultaneously stretched and compressed. It

page_text: is thus weakened and become filamentous, that is to say the pieces of leather are
lacerated and stretched, and the edges become fringed owing to the repeated
friction and fulling between the teeth of the rollers. After this and only then
the refining or pulping process begins.
The pulping operation is effected in the same machine by means of a series of
sharp cutters J formed in a block K of hard bronze or other metal. This block
is placed in the wall of the vat and is caused to advance towards the sharp-edged
teeth of the lower roller K when the pulping operation is to begin. This advance
may be effected by means of a worm-gear. L, or by other suitable means, the
leather being then shredded or pulped between the sharp teeth of the roller and
the cutter J.
Having now particularly described and ascertained the nature of the said
invention as communicated to me by my foreign correspondent and in what
manner the same is to be performed, I declare that what I claim is:-
I. The process of manufacturing leather pulp consisting in subjecting leather
waste previously macerated in hot water, to a simultaneous operation of washing,
stretching and fulling until said waste becomes filamentous, and then to a opera-
tion reducing it to a pulp substantially as described.
2. An apparatus for carrying out the process described in which all the
different operations of washing, stretching, fulling and pulping take place, con-
sisting of a vat having two compartments and provided with two rollers with teeth
engaging with each other so as to leave a slight clearance, a drum for washing and
a block K provided with sharp cutters, adapted to be advanced for the pulping
operation towards the lower roller, the teeth of which have sharp edges, and a pulp
for removing the pulp from one compartment into the other substantially as
described.
3. The combination and arrangement of parts constituting the complete
apparatus for use in the treatment of leather waste, substantially as described
and illustrated in the accompanying drawings.
Dated the 10th day of Oathan 1907
BOULT & WADE.
Agent for the Applicant.