Improvements in the Manufacture of Seamless Articles from Rubber.
Year: 1893

page_text: Date of Application, 5th Dec., 1893
Complete Specification Left, 5th Oct., 1894-Accepted, 17th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Seamless Articles from
Rubber.
I SAMUEL EDMOND STATHAM of Manor House, Levenshuline, Manchester, in
the County of Lancaster, Indiarubber Manufacturer and Engineer, do hereby
declare the nature of this invention to be as follows:-
-
My said invention relates to the manufacture of seamless rubber goods
produced by the employment of moulds in a novel and improved manner, whereby
I am enabled to make articles of various shapes, sizes and thickness such as could
not be commercially produced by similar methods heretofore in use.
In carrying my invention into effect I make a mould or core of the exact shape
or configuration of the object intended to be produced, which might for example
be a tobacco pouch, water bottle, doll, balloon or other article.
The mould may be
made of any suitable material, for example of earthenware or cast metal with a
smooth or enamelled surface. The mould is made hollow and is connected to a flexible
or other conduit, whereby steam, hot air or other heating fluid is conducted to the
interior of the mould, so as to keep it at any desired temperature. I also provide
a vessel containing a solution of fine india rubber and naphtha and I dip or
immerse the mould into the solution.
A thin skin or coating of rubber is thus formed upon the mould, the said coating
coinciding exactly with the configuration of the mould. The said coating is
allowed to dry by the evaporation of the naphtha, and I repeat the process of
dipping into the solution and drying the successive coatings until the necessary
thickness of the required object is obtained.
The mould with its rubber coating is then immersed in a vulcanizing mixture or
is vulcanized in any other suitable manner so as to give the proper nature and
elasticity to the coating. The coating is then stripped from the mould and the
desired seamless article is complete. The heating of the hollow mould in the
indicated manner, is a necessary part of the process, especially in the production of
larger objects of thin substance, as I am thereby enabled to counteract the effects
of the inevitable lowering of the temperature on the surface of the coating during
the process of drying. If the mould were not thus heated the rapid evaporation
or drying off, of the naphtha or volatile solvent employed, would absorb the heat
from the surrounding atmosphere and bring about the condensation of any
moisture therein contained. The layer of moisture thus formed on the surface of
the rubber coating on the mould would be fatal to the perfect union and adhesion
of the next coating to be applied by the next immersion in the solution, and would
also neutralize or render imperfect the final process of vulcanization. But by
keeping the mould hot as described, the evaporation of the solvent cannot lower
the temperature of the moulded surface below that of the surrounding atmosphere
so that condensation is prevented and a perfect union of the successive coatings
of rubber on the mould is obtained, while the final vulcanization of the moulded
object is not interfered with. To render my improved process still more effective
I prefer to dry the air before it is admitted to the chamber in which the moulding
operations are conducted. In order that the supply of dry air may be constantly
renewed, and to remove all moisture or exhalations, I draw the atmosphere from
the chamber at a point removed from the place of admission, by means of any
suitable air forcing or drawing apparatus, so that a body of dried and constantly
renewed atmosphere is always moving across or through the chamber. The
inoulds might be used singly and manually or they might be mounted on or in an
apparatus and dipped and dried automatically. For example a series of moulds

page_text: might be mounted on a revolving central steam drum or pipe with which the
interior of the moulds would be in communication. The surface of the moulds
might be fashioned with raised letters, words, ornaments or features which would
be reproduced in hollow relief on the moulded articles.
I am aware that small and simple objects of thick material, such as teats for
feeding bottles, and the like, have been produced by the process of dipping a
mould into a solution of rubber, but previous to my improvements it has been
impossible to produce on the same principle and in a commercially successful
manner seamless rubber articles of larger size and of more elaborate configuration.
The articles produced under my invention may be of any thickness down to the
maximum degree of fineness, in one piece and of perfect consistency and
impermeability. I do not confine myself to any particular goods so long as such
goods are capable of production by my improved method.
For example I might make tobacco pouches, wrappers for tobacco, dress shields
or arm gussets, dolls, balloons, balls and various other objects either smooth or
with relief or sunk mouldings, features ornaments or inscriptions.
TTL 4 3...
1308
E. K. DUTTON & Co.,
5, John Dalton Street, Manchester, Agents.
Improvements in the Manufacture of Seamless Articles from
Rubber.
I SAMUEL EDMOND STATHAM of Manor House, Levenshulme, Manchester, in
the County of Lancaster, Indiarubber Manufacturer and Engineer, 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, that is to say :-
My said invention relates to the manufacture of seamless rubber goods produced
by the employment of moulds in a novel and improved manner, whereby I am
enabled to make articles of various shapes, sizes and thickness such as could not
be commercially produced by similar methods heretofore in use.
In carrying my invention into effect 1 make a mould or core of the exact shape
or configuration of the object intended to be produced, which might for example
be a tobacco pouch, water bottle, doll, balloon or other article.
The mould may be made of any suitable material, for example of earthenware
or cast metal with a smooth or enamelled surface. The mould is made hollow and
is connected to a flexible or other conduit, whereby steam, hot air or other heating
fluid is conducted to the interior of the mould, so as to keep it at any desired
temperature. I also provide a vessel containing a solution of fine india rubber and
naphtha and I dip or immerse the mould into the solution.
A thin skin or coating of rubber is thus formed upon the mould, the said coating
coinciding exactly with the configuration of the mould. The said coating is
allowed to dry by the evaporation of the naphtha, and I repeat the process of
dipping into the solution and drying the successive coatings until the necessary
thickness of the required object is obtained.
The mould with its rubber coating is then immersed in a vulcanizing mixture or
is vulcanized in any other suitable manner so as to give the proper nature and
elasticity to the coating. The coating is then stripped from the mould and the
desired seamless article is complete. The heating of the hollow mould in the
indicated manner is a necessary part of the process, especially in the production of
larger objects of thin substance, as I am thereby enabled to counteract the effects
of the inevitable lowering of the temperature on the surface of the coating during
the process of drying. If the mould were not thus heated the rapid evaporation

page_text: or drying off, of the naphtha or volatile solvent employed, would absorb the heat
from the surrounding atmosphere and bring about the condensation of any
moisture therein contained. The layer of moisture thus formed on the surface
of the rubber coating on the mould would be fatal to the perfect union
and adhesion of the next coating to be applied by the next immersion in
the solution, and would also neutralize or render imperfect the final process
of vulcanization. But by keeping the mould hot as described, the evaporation
of the solvent cannot lower the temperature of the moulded surface below
that of the surrounding atmosphere so that condensation is prevented and a perfect
union of the successive coatings of rubber on the mould is obtained, while the final
vulcanization of the moulded object is not interfered with.
To render my improved process still more effective I prefer to dry the air before
it is admitted to the chamber in which the moulding operations are conducted.
In order that the supply of dry air may be constantly renewed, and to remove
all moisture or exhalations, I draw the atmosphere from the chamber at a point
removed from the place of admission, by means of any suitable air forcing or
drawing apparatus, so that a body of dried and constantly renewed atmosphere is
always moving across or through the chamber. The moulds might be used singly
and manually or they might be mounted on or in an apparatus and dipped and
dried automatically. For example a series of moulds might be mounted on a
revolving central steam drum or pipe with which the interior of the moulds would
be in communication. The surface of the moulds might be fashioned with raised
letters, words, ornaments or features which would be reproduced in hollow relief
on the moulded articles.
I am aware that small and simple objects of thick material, such as teats for
feeding bottles, and the like, have been produced by the process of dipping a
mould into a solution of rubber, but previous to my improvements it has been
impossible to produce on the same principle and in a commercially successful
manner seamless rubber articles of larger size and of more elaborate configuration.
The articles produced under my invention may be of any thickness down to the
maximum degree of fineness, in one piece and of perfect consistency and
impermeability.
I do not confine myself to any particular goods so long as such goods are
capable of production by my improved method. For example might make
tobacco pouches, wrappers for tobacco, dress shields or arm gussets, dolls, balloons,
balls and various other objects either smooth or with relief or sunk mouldings,
features ornaments or inscriptions.
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 process for moulding seamless rubber goods substantially as
hereinbefore described.
2. In the manufacture or moulding of seamless rubber goods, by dipping a
mould or moulds into a liquid bath of rubber and naphtha, forming the moulds
hollow and filling the interior with a body or current of heated fluid, for the
purpose and substantially as described.
3. In the manufacture of seamless rubber goods by dipping hollow heated moulds
into a rubber bath, keeping the chamber in which the manufacture takes place
charged with dry air or causing a current of dry air to move through the same,
in the manner and for the purposes herein before set forth.
Dated this 4th day of October 1894.
E. K. DUTTON & Co.,
5, John Dalton Street, Manchester, Agents.