IMPROVEMENTS IN THE MANUFACTURE OF SAFETY PAPER FOR BANKER'S CHEQUES, BILLS OF EXCHANGE, AND OTHER LIKE PURPOSES
Year: 1851

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
STONES, of Queen Hythe, in the City of London, Stationer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-fourth day of February, in the fourteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant, unto
me, the said William Stones, Her especial license, full power, sole privilege
and authority, that I, the said William Stones, my exors, adñiors, and assigns,
and such others as I, the said William Stones, my exors, adiñors, or assigns,
should at any time agree with, and no others, from time to time, and at
all times during the term of years therein meritioned, should and lawfully
might make, use, exercise, and vend, within England, Wales, the Town
of Berwick-upon-Tweed, and in all Her Majesty's Colonies and Plantations
abroad; and in the Islands of Jersey, Guernsey, Alderney, Sark, and Man,
my Invention of "IMPROVEMENTS IN THE MANUFACTURE OF SAFETY PAPER FOR
BANKER'S CHEQUES, BILLS OF EXCHANGE, AND OTHER LIKE PURPOSES;" in which
said Letters Patent is contained' a proviso obliging me, the said William
Stones, by an instrument in writing under my hand and seal, particularly
to describe and ascertain the nature of my said Invention, and in what manner
the same is to be performed, and to cause the same to be inrolled in Her
Majesty's High Court of Chancery within six calendar months next and imme-
diately after the date of the said in part recited Letters Patent, as in and
by the same, reference being thereunto had, will, more, fully and at large.
appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Stones, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, is particularly described
and ascertained in and by the following description thereof (that is to say):
The object of the present Invention is to manufacture a paper that will
indicate by discoloration of its surface when an attempt has been made to
extract written characters therefrom, and thereby to afford to bankers,
merchants, and others protection against forgery, or the tampering with
cheques, bills of exchange, and other important documents.
The Invention consists in the employment of iodine or bromine together
with ferrocyanide or ferricyanide of potassium and starch either in the manu-
facture or preparation of safety paper. For this purpose I find that iodine or
bromine may be used in any of their ordinary combinations with bases, but
iodine being the cheaper material I prefer its use to any compound of bromine.
Of the compounds of iodine I employ in preference that known as iodide of
potassium, that being the most readily attainable in the market, and in no
degree affecting the color of the paper: The mode of applying this substance
is by mixing it with the pulp or size, or the paper may be saturated with a
solution of the metallic iodide. The ferrocyanide or ferricyanide of potassium
I prefer to mix with the size, but it may be applied subsequently to the sizing,
as in the case of the metallic iodide. The starch I propose to mix with the
pulp in the engine, but it may, like the other chemical ingredients, be used in
an after stage of the process. The proportions of these several materials
which I propose to employ for rendering paper sensitive to the action of
re-agents are by no means absolute, but as a guide I may say that I have
found the following to answer the purpose; (viz,) for a ream of post, weighing
about eighteen pounds, one ounce iodide (or bromide) of potassium, quarter of
an ounce of ferrocyanide (or ferricyanide) of potassium, one pound of starch.
On the application to paper, prepared as above set forth, of re-agents to
dissolve out or absorb any ink markings therefrom, the tendency will be to
break up one of the salts named; thus, on the application of chlorine or
mineral acids the iodine will be liberated, and combining with the starch will
form an insoluble iodide of starch of a dark color; further, the iron which ink
generally contains being attempted to be dissolved by either vegetable or
mineral acids, the ferrocyanide of potassium will combine with it in solution
and form the well known prussian blue compound, which will become diffused
over the adjacent portion of the paper.
Having now described my Invention, and the manner of carrying the same
into effect, I wish it to be understood that I do not claim the chemical

page_text: substances above named when separately used as an ingredient in paper; but
what I claim under the above in part recited Letters Patent is, the application
and use of iodine (or bromine), in its combined state with a base of ferro-
cyanide (or ferricyanide) of potassium and of starch, for the purpose above
set forth.
In witness whereof, I, the said William Stones, have hereunto set my
hand and seal, this Twenty-third day of August, in the year of our
Lord One thousand eight hundred and fifty-one.