Improved Method of or Process for Manufacturing Leather Articles Coated with India Rubber.
Year: 1897

page_text: Date of Application, 23rd July, 1897-Accepted, 2nd Apr., 1898
COMPLETE SPECIFICATION.
Improved Method of or Process for Manufacturing Leather Articles
Coated with India Rubber.
I, RAPHAEL SCHWARZWALD, of Grosse Bleichen 33, Hamburg, in the German
Empire, Merchant, 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:-
-
This invention consists in an improved method. of or process for combining
leather articles with a coating of india rubber. Leather and india rubber are two
materials which combined in a correct manner offer great advantages for some
purposes. In uniting the leather with the rubber it is especially important not
only to obtain a perfect combination or adhesion of the two materials but also to
avoid the formation of folds or wrinkles.
This object has been successfully attained in a perfect manner by this invention,
which mainly consists in the process of manufacturing combined leather and india-
rubber articles by first cutting out bark tanned leather into the shape required for
the article to be made, such as a shoe, boot, satchel, portmanteau covering and
the like, then placing it upon a last, form or mould, covering it with india rubber
sheeting and vulcanising the plated or coated articles in an air bath unconfined
in wrappers or enclosures. The kind of leather used and manner of vulcanising
is of great importance in this process and only if the material is correctly selected
and vulcanised in the manner herein described a good and saleable article is
obtained.
The vulcanisation of indiarubber articles of all kinds can be effected in several
ways as generally known. In each case it is necessary to cause the sulphur
previously admixed with the indiarubber to melt and form an intimate chemical
combination with the rubber by which the latter obtains its permanent elasticity
and capacity of resisting external influences, such as moisture and changes of
temperature.
An extensively used method of vulcanising is by the use of a vulcanising
boiler. The articles to be vulcanised are enclosed in a hermetically sealed casing
and steam is admitted to the same and acts for a longer or shorter period according
as a lower or higher degree of vulcanisation is intended. Another method con-
sists in subjecting the articles to be vulcanised to the action of hot metal plates.
Both these processes are found unsuitable for vulcanising articles composed of
leather with rubber sheeting, and for the purpose of this invention it is absolutely
necessary to subject the articles in question to vulcanisation in an air bath, that is
to say in a chamber filled with heated dry air, and without enclosing them in
moulds or the like.
Besides the vulcanising process the leather as mentioned has to be selected and
I have found that bark tanned leather is best suited for coating or plating with
india rubber. If, for instance, foot coverings with rubber coating are to be made,
the following process is carried out:-
The leather is cut out into the shape required for the foot' covering to be made,
and fitted on to a last. In doing so preferably a piece of india rubber sheeting of

page_text: the shape of the insole is placed between the insole and the edges of the upper
folded under the same, and another piece of rubber between the latter and the
outer leather sole after which the sole and those parts of the uppers to be coated are
further covered by a layer of rubber sheet. The rubber is firmly pressed upon
the leather while being laid on and the parts that are projecting or superfluous are
trimmed off, and the edges firmly pressed upon the uppers, caps or heel parts by
pressing and smoothing them. The outer sole may be formed of several layers
of rubber sheeting alternating with layers of thin leather cloth, felt, cork or the
like, and a similar mode of formation may be used for the heel parts.
When the foot covering has been brought into the correct shape and externally
finished it is subjected to the vulcanising process in the hot air chamber while on
the last and without being confined externally. When the vulcanisation is
finished a foot covering is obtained in which the leather and indiarubber are as
intimately united as if they consisted of one piece, while the formation of folds or
wrinkles is avoided and the leather is in no way injured, as would be the case if
steam were used for vulcanising.
The foot coverings thus made have the advantages that they keep the feet always
warm, that the wearer treads without noise and more lightly, is less soon fatigued
and the shakings, which during long marches exercise a detrimental effect on the
whole body, are obviated. The walk is elastic and the foot is protected against
injurious influences, slipping is prevented. By this method foot coverings can
be produced inside of which neither pegs nor sewn seams are used, and a perfectly
smooth insole without any seams or pegs is obtained, so that in this respect also
the greatest possible comfort of the wearer is assured.
In some cases the foot coverings may be finished in the usual way and after-
wards coated with indiarubber sheeting on the sole and on the lower part of the
uppers next to the sole, or all over the uppers, as may be desired. In the manner
herein before described the most various kinds of foot coverings, such as slippers,
shoes, low shoes, Wellington boots, fishing boots, laced and buttoned boots and
the like with leather uppers, and with soles of leather, or of indiarubber with
insertions, can be covered entirely or in parts only with a perfectly durable india-
rubber coating which does not split or pull off. The rubber coated leather foot
coverings are cleaned by simply washing them, so that the tedious polishing
with blacking is obviated.
The indiarubber sheets or plates can be made glossy or dull, or with a dull
gloss, or be lacquered and ornamented with any sort of patterns or colours, as in
the present position of the rubber manufacture, india rubber can be produced in
most various colours and patterns.
By the process hereinbefore described other articles made of leather, for
instance portmanteaux, hat boxes, scabbards, cartridge pouches, helmet bodies and
the like, which up to the present have to be protected against wet by a special
covering or by lacquering, can be provided with a coating of indiarubber during
their manufacture. This invention is particularly important for cartridge
pouches, for until now there have always been difficulties in protecting the
cartridges against damp. A leather pouch covered with indiarubber is obviously
quite impermeable to dampness.
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 improved method of manufacturing leather articles coated with india
rubber by covering said articles when formed of leather with india rubber sheet-
ing entirely or partly and subjecting them to the vulcanising process in a hot
air bath, substantially as herein before described.
2. The improved process of manufacturing foot coverings by vulcanising in
a hot air chamber bark tanned leather cut into the required shapes, fixed on lasts

page_text: and connected by and covered with plain coloured, smooth or embossed india-
rubber sheeting, free on the lasts without being wrapped up or enclosed substan-
tially as herein before described.
R. J. URQUHART,
37, Barton Arcade, Manchester, 6, Clayton Square, Liverpool,
Consulting Engineer and Patent Agent.