IMPROVEMENTS IN THE MANUFACTURE AND APPLICATIONS OF HYPOSULPHITE AND SIMILAR COMPOUNDS OF ZINC
Year: 1852

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
Fields, in the County of Middlesex, and of Glasgow, North
Britain, Gentleman, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE AND APPLICATIONS OF HYPOSULPHITE AND SIMILAR
COMPOUNDS OF ZINC."-A communication.
PROVISIONAL SPECIFICATION left by the said John He
Johnson at the Office of the Commissioners of Patents, with his
Petition, on the 16th October 1852.
I. JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
of Middlesex, and of Glasgow, North Britain, Gentleman, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE
MANUFACTURE AND APPLICATIONS OF HYPOSULPHITE AND SIMILAR COMFOUNDS
OP ZINC" to be as follows, that is to say:
The new manufacture of useful preparations of zinc is obtained in
the following manner:-A solution is made of potass or caustic soda, or
any other caustic alkali, in sufficient quantity for the object in view.
This caustic mixture, being turned into a proper vessel, is boiled from

page_text: three to five hours, so as to form a very concentrated solution. In the
process of boiling, flour of sulphur is added, and the whole is stirred up
together until the potass, &c. cannot be separated from the sulphur.
When the liquor is in this state, a current of sulphurous acid gas is
passed through it, so as to obtain a hyposulphite of potass.
The solution is then allowed to cool, and the liquid having become
very clear, is drawn off into another vessel containing acetate of zinc or
any other salt of zinc possessing similar properties.
The mixture of these two solutions immediately causes a precipitate
of zinc to fall in the form of a white powder, which is termed the
hyposulphite of zinc.
In place of the entire process above described, the sulphurated
potass liquor having been allowed to cool, may be mixed with a solu-
tion of sulphate of zine. The mixture of the two will cause the zinc
held in solution to precipitate itself in the form of a white powder, as
before, which is termed a bi-sulphuret of zinc. These preparations of
zinc are then filtered and dried, and pounded to an impalpable powder,
and in this state are applicable to a variety of purposes. One of the
applications which has been found valuable is the combination with
caoutchouc, which is effected by the ordinary machinery for that pur-
pose; and it is found that the composition so obtained, after being
subject to a heat of from 120 to 150 degrees centigrade for a period of
from 3 to 5 hours, is ready for use.
The principal object of this Invention being the manufacture or
obtainment of byposulphite and bi-sulphuret, or other analogous prepa-
rations of zinc, and their application to the treatment of caoutchouc and
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office, on the 16th April 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
Joux HENRY Jouxson, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of Glasgow, North Britain, Gentleman, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of October, in the year
of our Lord One thousand eight hundred and fifty-two, in the sixteenth
year of Her reign, did, for Ierself, Her heirs and successors, give and
grant unto me, the said John Henry Johnson, Iler special license that
I, the said John Henry Johnson. my executors, administrators, and
assigns, or such others as I, the said John Henry Johnson, my
exécutors, 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, exer-
cise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "IM-
PROVEMENTS IN THE MANUFACTURE AND APPLICATIONS OF HYPOSULPHITE AND
SIMILAR COMPOUNDS OF ZINC," being a communication to me from abroad,
upon the condition (amongst others) that I, the said John Henry
Johnson, by an instrument in writing under my hand and seal; should
particularly describe and ascertain the nature of the said Invention, and
in what manner the same is to be performed. and cause the same to
be filed in the Great Seal Patent Oflice within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of the 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:
The said Invention relates to an improved system or mode of pre-
paring the hyposulphite of zinc, and to the application of the same to
various manufactures, and more particularly to the manufacture of
caoutchouc. The hyposulphite of zinc is obtained in the following
manner -A solution of potass or caustic soda, or other caustic alkali,
is prepared and boiled in a suitable vessel for four or five hours, in
order to obtain a highly concentrated solution. During the process of
boiling, flour of sulphur is added, and the solution is stirred up, so that
the potass and sulphur are thoroughly combined. A current of sul-
phurous acid gas is then passed through the sulphurated liquor, and a
solution of hyposulphite of potass is thereby obtained. This solution is

page_text: then allowed to stand for a time until cool, when it is poured in a clean
state into another vessel containing a solution of acctate of zinc or any
other similar salt of zinc. The admixture of these two solutions causes
a precipitate of zinc to fall in the form of a white powder, which may
he called the hyposulphite of zinc.
A modification of the above process may also be used to obtain a
somewhat similar preparation of zinc, by dispensing with the current
of sulphurous acid gas mentioned in the last process, in place of which
the solution of potass, after having stood and cleared, is turned into a
solution of sulphate of zine. The admixture of the solution of sulphuretted
potass with the solution of sulphate of zinc will cause the zinc held in
solution to precipitate itself in the form of a white powder, similar to
that above described, and which may be termed a bi-sulphuret of zinc.
The preparation of zinc for use, obtained by either of the above
methods, is collected, filtered, and dried, and is then reduced to an
impalpable powder. When intended for the manufacture of caoutchouc,
the preparation of zinc and the caoutchouc are well worked together,
and subjected to a heat of from one hundred and twenty degrees to
one hundred and fifty degrees centigrade, during a space of time which
may be varied from three to five hours. The caoutchouc thus pre-
pared is of a white color, free from sulphur, and does not present
the inconveniences of that prepared with lead, which is black, or
becomes black by contact with sulphurous gas. This preparation
of zinc is particularly applicable for the manufacture of caoutchouc
where the articles to be made are to be colored, as it is found that
the caoutchouc so prepared receives the coloring matter with great
facility; and by the use of these ingredients in the manufacture of
caoutchouc the bleaching or discoloring process necessary in the ordinary
process is dispensed with.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion, that I do not confine
or restrict myself to the precise details or arrangements which I have
had occasion to describe or refer to, as many variations may be made
therefrom without deviating from the principles or main features of the

page_text: said Invention. But what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in
part recited Letters Patent, is,―
First, the systems or modes of producing the hyposulphite and bi-
sulphurets of zinc, as herein-before described.
Second, the system or mode of treating caoutchouc by incorporating
or combining with it a hyposulphite or a bi-sulphuret of zinc, or any
similar preparation of zinc obtained by the methods herein-before
lescribed.
In witness whereof, I, the said John Henry Johnson, have here-
unto set my hand and scal, the Sixteenth day of April, One
thousand eight hundred and fifty-three.
J. HENRY JOHNSON. (L.S.)