IMPROVE- MENTS IN THE TREATMENT OF GELATINOUS TISSUES OF GELATINE AND GUM AND OF COMPOUNDS CONTAINING SUCH SUBSTANCES
Year: 1866

page_text: Sealed the 11th June 1867, and dated the 15th December 1866.
PROVISIONAL SPECIFICATION left by the said Joseph Wilson Swan.
at the Office of the Commissioners of Patents, with his Petition on the
. 15th December 1866.
I, JOSEPH WILSON SWAN, of Gateshead, in the County of Durham,
Chemist, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE TREATMENT OF GELATINOUS TISSUES OF GELATINE AND GUM AND OF
COMPOUNDS CONTAINING SUCH SUBSTANCES," to be as follows:-
My Invention consists in the use of salts of the sesquioxide of chromium
(as for example, sulphate of the sesquioxide of chromium, or the substance
known as chrome alum) as a means of rendering gelatine or gum or com-
pounds containing those substances insoluble in water.
My Invention is applicable to various uses, for example, to the fixing of
pigments and dyes in calico printing when the pigment or dye is thickened
with gelatine or gum; to the tanning of skins and hides; to the fixing of
photographs mounted with gelatine; to the fixing of prints produced in
gelatinous ink to the rendering insoluble of gelatine used as a glaze or
Price 6d.1

page_text: varnish, or for the purpose of waterproofing; to the production of sheets of
insoluble gelatine; to the preparation of photographic paper sized or coated
with gelatine or gum.
In applying my Invention to calico printing I either add a solution of the
chromic salt to the thickened color or dye, or I apply a solution of the
chromic salt to the fabric to be printed either before or after printing, or
instead of the said chromic salt I employ chromate or bichromate of potash,
or its equivalent, and act upon it with any acid suitable for decomposing the
chromate or bichromate, and producing the compound of chromic oxide
required to render insoluble the gelatine or gum contained in the mixture of
color.
In tanning I immerse the skins or hides in a solution of the chromic salt,
or in a solution of chromate or bichromate of potash, or any equivalent salt;
the said chromate or bichromate being decomposed in the skin or hide by
the action of a suitable acid, so as to produce the required compound of
chromic oxide.
In fixing prints produced in gelatinous ink I add a solution of the chromic
salt to the gelatinous ink, or I wet the paper on which the print is produced
with a solution of the chromic salt, or I introduce into the gelatinous ink
a chromate or bichromate, and effect the required decomposition of the
chromate or bichromate by the action of a reducing agent, as before mentioned.
In fixing photographic prints mounted with gelatine I immerse the
mounted prints in a solution of the chromic salt, or 1 mount the prints on
paper wetted with a solution of the said salt.
In rendering gelatine insoluble when used as a glaze or varnish, or when
formed into a sheet, I apply a solution of the chromic salt to the gelatinised
surface or sheet, or I immerse the surface or sheet in the solution.
I also propose to obtain waterproof fabrics by saturating them with a
solution of gelatine, rendering the same insoluble, in the manner above
explained.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of December, in the year of our
Lord One thousand eight hundred and sixty-six, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Joseph Wilson Swan, Her special licence that I, the said Joseph
Wilson Swan. my executors, administrators, and assigns, or such others
as I, the said Joseph Wilson Swan, my executors, administrators. and
assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom
of Great Britain and Ireland. the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN THE TREATMENT OF GELATINOUS TISSUES OF
GELATINE AND GUM AND OF COMPOUND3 CONTAINING SUCH SUPSTANCES," upon
the condition (amongst others) that I, the said Joseph Wilson Swan, my
executors or administrators, by an instrument in writing under my, or their,
or one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to
be performed. and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that I, the said Joseph Wilson Swan. do hereby
declare the nature of my said 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 Invention consists in the use of salts of the sesquioxide of chromium,
as for example, sulphate of the sesquioxide of chromium or the substance
known in commerce as chrome alum, as a means of rendering gelatine or
gum (Senegal or Arabic) or compounds containing those substances
insoluble in water.
My Invention is applicable to various uses, for example, to the fixing of
pigments and dyes in printing and dyeing textile fabrics when the
pigment or dye is thickened with gelatine or gum; to the tanning of
skins and hides; to the fixing of photographs mounted with gelatine;
to the fixing of prints produced in gelatinous ink; to the rendering
insoluble of gelatine used, as a glaze or varnish, or for the purpose of
waterproofing; to the production of sheets of insoluble gelatine, and to the
preparation of photographic paper sized with gelatine or gum.
In applying my Invention to calico printing I either add a solution of chrome
alum or other suitable salt of the sesquioxide of chromium to the thickened

page_text: color or die, or I apply a solution of the above-mentioned salt or analogous
salt to the textile fabric either before or after printing, or where the addition
of a chromate or bichromate would not be injurious to or incompatible with
the mixture of colour or dye instead of the said salt of the sesquioxide of
chromium I add to the color or dye chromate or bichromate of potash or other
suitable chromate or bichromate, and after printing act upon it by light, or by
citric acid or other acid suitable for decomposing and reducing the chromate
or bichromate so as to produce the compound of the sesquioxide of chromium
required to render insoluble the gelatine or gum contained in the mixture of
colour or dye. When the fixing solution is applied to the fabric before or after
printing it may consist of five parts by weight of chrome alum and one
hundred parts of water, and when the fixing solution is added to the
thickened color or dye one part of the fixing solution composed as above
mentioned may be added to every ten parts of the thickened color or dye.
In tanning I immerse the skins or hides in a solution containing about one
per cent. of chrome alum, or in a solution of chromate or bichromate of potash
or other suitable chromate or bichromate, and I decompose the said chromate
or bichromate in the skin or hide by means of oxalic or other suitable acid
so as to produce by the decomposition and reduction of the said chromate
or bichromate the required compound of chromic oxide.
In fixing prints produced in gelatinous ink I add a solution of a salt of
the sesquioxide of chromium, by preference chrome alum, to the gelatinous
ink in the proportion of one part of a ten per cent. solution of chrome alum
to ten or twenty parts of the gelatinous ink, or I apply the above-mentioned
solution to the paper on which the print is produced, or is to be produced.
or I introduce into the gelatinous ink a chromate or bichromate, and
effect the required decomposition of the chromate or bichromate by the
action of light or other suitable reducing agent.
In fixing photographic prints mounted with gelatine I immerse the
mounted prints in a solution of a suitable salt of the sesquioxide of
chromium, by preference chrome alum, consisting of about one part of
the salt to twenty parts of water, or I mount the prints on paper wetted
with the said solution, or employ a mixture consisting of about ten
parts of a solution of gelatine or gum, and one part of the above-mentioned
solution as the cement wherewith the prints are mounted, the mixture
being made immediately previous to using in consequence of the tendency
of the mixture to solidify after the addition of a solution of chrome alum.
In rendering gelatine insoluble when used as a glaze, sizing, or varnish for
paper, or when formed into a sheet. I apply a solution containing about five

page_text: per cent. of chrome alum or other suitable salt of the sesquioxide of chromium
to the gelatinized surface or gelatine sheet, or I immerse the surface or sheet
in the above-mentioned solution, or I form a sheet from a mixture of a
solution of gelatine and the above-mentioned solution of chrome alum.
I also propose to obtain waterproof fabrics by saturating them with a
solution of gelatine, rendering the same insoluble by the action of a solu-
tion of chrome alum or other suitable salt of the sesquioxide of chromium,
the said solution being applied in any convenient manner.
Referring to the above-mentioned illustrations of the mode in which
my Invention is carried out, I wish it to be understood that I do not limit
myself to the use of chrome alum, for I have ascertained that other salts of
analogous composition, that is to say, such as have for their base the
sesquioxide of chromium and are soluble in water, may generally be sub-
stituted for chrome alum; I also wish it to be understood that I do not
limit myself to the employment of the specified quantities.
Having explained the nature of my Invention, and the manner in which
it is carried into effect, I claim the use of the above-mentioned salts of the
sesquioxide of chromium as a means of rendering gelatine and gum in-
soluble, and the direct or indirect application of the said salts to the
industrial purposes above specified.
In witness whereof, I, the said Joseph Wilson Swan, have hereunto
set my hand and seal, this Fourteenth day of June, in the year of
our Lord One thousand eight hundred and sixty-seven.
5 Witness,
JAMES BLAKEY,
3, Mary Street,
Newcastle-on-Tyne.
JOSEPH WILSON SWAN. (L.S.)