IMPROVEMENTS IN THE MANU- FACTURE OF DOUBLE TEXTURE WATERPROOF FABRICS
Year: 1876

page_text: LETTERS PATENT to Thomas Forster, of the India-rubber Works, Streatham, in
the County of Surrey, for the Invention of "IMPROVEMENTS IN THE MANU-
FACTURE OF DOUBLE TEXTURE WATERPROOF FABRICS."
Sealed the 16th March 1877, and dated the 10th October 1876.
PROVISIONAL SPECIFICATION left by the said Thomas Forster at the Office
of the Commissioners of Patents on the 10th October 1876.
THOMAS FORSTER, of the India-rubber Works, Streatham, in the County of
Surrey. 'IMPROVEMENTS IN THE MANUFACTURE OF DOUBLE TEXTURE WATERPROOF
FABRICS."
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It has been the usual practice hitherto in using the chloride of sulphur combined
with bisulphide of carbon as a vulcanizing agent to apply the same only to the
rubber surfaces of waterproof goods, on account of the corrosive action of the
chloride on the textures.
According to my Invention I apply the above compounds direct to the cloth
surfaces of double-texture waterproof fabrics, be they woollen, silk, or cotton
fabrics, and after so doing subject the said fabrics to the action of an alkali, by
preference ammonia, which by neutralizing the hydrochloric acids prevents its
injurious action.
It is essential in proofing goods that are to be so treated that care be taken to
prevent the strong adhesion of the india-rubber to the fabric which is caused by
this treatment, and would prevent the making-up of the goods by separating the
edges of the fabric in the usual way, and which is well understood. To prevent
this I give the fabrics a first coating of india-rubber compound.
The following I find answers the purpose well:-50 parts coal oil, 10 parts india-
rubber, 10 parts silicate of magnesia or French chalk; after which I apply the
necessary quantity of india-rubber and double the goods in the usual way; after
this the goods are hung up for a day or two to dry, and then proceed to vulcanize
them with the chloride of sulphur and bisulphide of carbon; one part of the
former to fifty of the latter will do the work well. In about half an hour after the
goods have been so prepared I hang them in a close warın chamber, on the floor of
which I place vessels containing liquor ammonia, and after exposure to the vapour
of it for about 12 hours the goods are finished.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Forster in the Great Seal Patent Office on the 10th April
1877.
THOMAS FORSTER, of the India-rubber Works, Streatham, in the County of
Surrey. "IMPROVEMENTS IN THE MANUFACTURE OF DOUBLE TEXTURE WATERPROOF
FABRICS."
It has been the usual practice hitherto in using the chloride of sulphur combined
with bisulphide of carbon as a vulcanizing agent to apply the same only to the
rubber surfaces of waterproof goods, on account of the corrosive action of the
chloride on the textures.
According to my Invention I apply the above compounds direct to the cloth
surfaces of double-texture waterproof fabrics, be they woollen, silk, or cotton
fabrics, and after so doing subject the said fabrics to the action of an alkali, by
preference ammonia, which by neutralizing the hydrochloric acid (resulting from the
decomposition of the chloride of sulphur) prevents its injurious action.
It is essential in proofing goods that are to be so treated that care be taken to
prevent the strong adhesion of the india-rubber to the fabric which is caused by
this treatment, and would prevent the inaking-up of the goods by separating the
edges of the fabric in the usual way, and which is well understood. To prevent this
I give the fabrics a first coating of india-rubber compound, which after vulcanizing
will separate freely.
.
The following I find answers the purpose well:-50 parts coal oil, 10 parts india-
rubber, 10 parts silicate of magnesia or French chalk; after which I apply the
necessary quantity of india-rubber and double the goods in the usual way. Other
pigments may be substituted for French chalk. After this the goods are hung up
for a day or two to dry, and I then proceed to vulcanize them with the chloride of
sulphur and bisulphide of carbon, one part of the former to fifty of the latter will
do the work well. I prefer to pass the goods in contact with the upper surface of a
roller which on the under side dips into a trough containing the vulcanizing liquid,
and so I apply the liquid to the cloth surface of the fabric, as heretofore it has been
applied to the rubber surface. In about half an hour after the goods have been so
prepared I hang them in a close warın chamber, on the floor of which I place vessels
containing liquor ammonia, and after exposure to the vapour of it for about 12 hours
the goods are finished.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I claim as my improvements
in the manufacture of double-texture waterproof fabrics, vulcanizing by means of
chloride of sulphur and neutralizing the resulting hydrochloric acid remaining in
the cloth by means of alkaline vapour, substantially as described.
In witness whereof, I, the said Thomas Forster, have hereunto set my hand
and seal, this Ninth day of April, in the year of our Lord One thousand
eight hundred and seventy-seven.
THOS. FORSTEK. (L.S.)