Year: 1894

page_text: Date of Application, 24th Jan., 1894
Complete Specification Left, 23rd Aug., 1894-Accepted, 24th Jan., 1895
I, ALFRED JULIUS BOULT, of 323, High Holborn, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be as
follows:-
In my Patent No. 12,595 of the 27th June 1893 I have claimed the use of
vaseline liquefied by means of heat and applied to a special layer of very slightly
vulcanized indiarubber placed in the interior of an indiarubber tube lined with
canvas and itself provided with an inner lining, the whole for the purpose of
obtaining a pneumatic tyre which will not collapse on being punctured.
I had in fact remarked that ordinary solid vaseline liquefied by heat is very
easily absorbed by slightly vulcanized indiarubber, whereas at ordinary temperature
the absorption of the vaseline takes place very slowly and is practically speaking
nil. Besides when the action of the heat upon the vaseline has ceased, the liquefied
vaseline upon again assuming a solid condition has only a very slight tendency to
penetrate into the whole mass of indiarubber, that is to say into the outer layer
which it might damage if it penetrated so far.
Basing myself again on these various considerations I have devised the employ-
ment of various substances in combination with ordinary vaseline or other similar
matter which will bring about a more advantageous result; the substances which,
like vaseline, are clearly distinct from ordinary oils the use of which in the treatment
of indiarubber is already known, are all solid at ordinary temperatures, but possess
the advantage of melting at the comparatively low temperatures of 85 to 170°
Fahrenheit. These substances are, paraffine, stearine, ozokerit, animal wax,
vegetable wax, stearic acid, cocoa-butter, spermaceti, and other similar substances.
I could even make use for the same purpose of ordinary fat or grease solid at
ordinary temperature.
These substances being very hard in the ordinary temperature of our country
they can only be used alone in warm countries. In order to be able to use them in
Europe I preferably mix them with solid vaseline so as to obtain a composition of a
suitable consistency at ordinary temperature, i.e. neither too soft nor too hard,
which will melt at a low temperature which I am able to determine in advance.
An excellent mixture or composition of this kind could, by way of example, be
obtained by using :-
"
17

page_text: in the present Patent, having a remarkable consistency, they not only have no
tendency to penetrate into the external layer of indiarubber which they would thus
gradually damage as stated above, but as in addition they do not soften the india-
rubber as much as a liquid oil would, the indiarubber retains its elasticity and
excellent results are obtained even when these substances are used in small
quantities.
Besides in the event of a puncture or perforation which would allow the air to
escape, it would suffice to rub the walls of the pneumatic tyre one against the other
at the spot where the opening has been made in order to cause some particles of
the thickened matter which had adhered to the walls of the tube to penetrate into
the opening and consequently to close it up.
The present application for a Patent has essentially for its object to reserve for
myself the exclusive right of a process such as above described by means of which
I can at any desired moment arrest the absorption by the indiarubber of the liquefied
matter in order to prevent the subsequent dissociation of the molecules of the
external vulcanized indiarubber which might take place in the case of the process
described in my Patent No. 12595 of the 27th June 1893.
Dated this 24th dox of January 1801
W. P. THOMPSON & BOULT,
Of London, Nottingham, Liverpool, and Manchester,
Agents for the Applicant.
I, ALFRED JULIUS BOULT of 323 High Holborn 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 aud
ascertained in and by the following statement :-
In my Patent No. 12,595 of the 27th June 1893, I have claimed the use of
vaseline liquefied by means of heat and applied to a special layer of very slightly
vulcanized india rubber placed in the interior of an india rubber tube lined with
canvas and itself provided with an inner lining, the whole for the purpose of
obtaining a pneumatic tyre which will not collapse on being punctured.
I had in fact remarked that ordinary solid vaseline liquefied by heat, is very
easily absorbed by slightly vulcanized india rubber, whereas at ordinary temperature
the absorption of the vaseline takes place very slowly and is practically speaking nil.
Besides when the action of the heat upon the vaseline has ceased, the liquefied
vaseline upon again assuming a solid condition has only a very slight tendency
to penetrate into the whole mass of india rubber, that is to say into the outer
layer which it might damage if it penetrated so far.
Basing myself again on these various considerations, I have devised the employ-
ment of various substances in combination with ordinary vaseline or other similar
matter which will bring about a more advantageous result; the substances which, like
vaseline, are clearly distinct from ordinary oils, the use of which in the treatment of
india rubber pneumatic tyres is already known, are all solid at ordinary temperatures,
but possess the advantage of melting at the comparatively low temperatures of 85
to 170° Fahrenheit. These substances are: paraffin, stearine, ozokerit, animal
wax, vegetable wax, stearic acid, cocoa-butter, spermaceti, and other similar
substances. I could even make use for the same purpose of ordinary fat or grease
solid at an ordinary temperature, or of lanoline.
The greater part of the substances, above named, being very hard at ordinary
temperatures can only be used alone in warm countries. In order to be able to use

page_text: them in Europe, I preferably mix them with solid vaseline or grease, so as to obtain
a composition of a suitable consistency at an ordinary temperature, i.e. neither too
soft nor too hard, which will melt at a low temperature which I am able to determine
in advance.
11
13 1
them in Europe, I preferably mix them with solid vaseline or grease, so as to obtain
a composition of a suitable consistency at an ordinary temperature, i.e. neither too
soft nor too hard, which will melt at a low temperature which I am able to determine
in advance.
An excellent mis
obtained by using :
composition of this kind could, by way of example, be
part of stearine.
In order to be able to make use of these mixtures, I melt the substances together
by heat and I place them in contact with the very slightly vulcanized india rubber
situated in the interior of my pneumatic tyre and held by the linen, and I expose
the latter to a suitable temperature during a sufficient length of time.
The great advantage of the employment of the substances or of a mixture similar
to those described above lies in the fact that the materials the use of which I claim
in the present Patent, having a remarkable consistency, they not only have no
tendency to penetrate into the external layer of india rubber which they would
thus gradually damage as stated above, but as in addition they do not soften the
india rubber, as much as a liquid oil would, the india rubber retains its elasticity
and excellent results are obtained even when these substances are used in small
quantities.
Besides in the event of a puncture or perforation which would allow the air to
escape, it would suffice to rub the walls of the pneumatic tyre one against the other
at the spot where the opening has been made, in order to cause some particles of
the thickened matter which had adhered to the walls of the tube to penetrate into
the opening and consequently to close it up.
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:
The new process for rendering self-closing pneumatic tubes formed with ordinary
vulcanized india rubber lined with canvas, wherein is applied a layer of slightly
vulcanized india rubber similarly lined with canvas, such as that described in my
Patent No. 12595 dated the 27th June 1893, this process consisting in inflating
and compressing the inner layer of the said tube, by causing this layer to absorb,
by the aid of heat, a suitable quantity of some material readily absorbable by india
rubber, but which is solid or viscous at an ordinary temperature, such as the
substances and mixtures hereinbefore indicated; substantially as above described
and for the purpose set forth.
Dated the Twents third day of August 1894