Alteration of Cheques, Bills of Exchange, and other Documents.
Year: 1888

page_text: Date of Application, 11th Feb., 1888
Specification Accepted, 29th Mar., 1888
Alteration of Cheques, Bills of Exchange, and other Documents.
I, JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex,
Gentleman do hereby declare the nature of this Invention which has been com-
municated to me from abroad by Jules Albert Schlumberger of 1 rue Bausset, Paris
in the Republic of France Chemist and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement :-
This Invention relates to the preparation of choques and other documents with the
object of rendering it impossible to make fraudulent alterations thereon.
In the Specifications to Letters Patent granted to Jules Albert Schlumberger and
dated September 9th 1886 No. 11491 and January 24th 1887 No. 1076 processes are
described for the preparation of cheques and the like with the same object and
the present Invention consists in further improvements in the processes or treatment
as hereinafter described whereby any alteration in the writing is exposed or made
evident either by a blue colour or stain appearing on the printed or impregnated part
or by a dark or brown stain or colour according as acids, alkalis, or chlorides are
employed for removing the writing.
In the aforesaid Specification No. 11491 certain cryptographic inks are described
being prepared with a base of a salt of inanganese or cobalt with the object of causing
signs or characters of a bistre tinge to appear on the paper printed with these inks
directly such paper is acted on by a decolourising chloride. According to the
present Invention two superposed or successive applications or impressions forming a
guilloche ground are applied to the paper. The first ground is produced by printing
with a colour prepared with a base of a salt of protoxide of iron such as sulphate of
protoxide of iron or preferably of lactate of iron the water of crystallisation being
removed as completely as possible. Any suitable quantity of sulphate of manganese
is mixed with this iron colour and to facilitate the printing it is preferable to employ a
gummy solution prepared with dextrine, glucose and glycerine as in the case of
ordinary removeable colours. In certain cases in place of employing a printing
process the paper is impregnated with metallic solutions of iron and manganese in a
state of fine division by means of a spray producing apparatus working with a jet of
air or steam.

page_text: After the paper has received the impression of the first ground or has been
impregnated as described, a second similar or different design or pattern is produced
over the first ground with a colour the base of which is a fatty varnish ground with
ferrocyanide of potassium previously dried.
This method of printing or preparing the paper causes attempts at falsification or
fraudulent alterations in the writing by means of acids, alkalies or chlorides to be
instantaneously exposed.
If preferred the prussiate (ferro cyanide) of the removeable colour may be applied
to the paper in the first instance with the requisite quantity of a salt of manganese
being afterwards covered by a second ground in fatty colour with a base of protoxide
of iron as hereinbefore described.
To render the effect more conspicuous oxalate of aniline (preferably to other salts
of aniline), sulphanilic acid or a salt or homologue thereof or diphenylamine or a salt
of naphthylamine (as pure as possible). This addition of colour forming derivatives of
coal tar is very advantageons as chlorides or permanganates of potash reacting upon
these compounds when employed to efface the writing produce very permanent brown
stains rendered still more apparent by those produced by the oxide of manganese.
By means of these combinations a paper is obtained which shows two clearly
defined designs one in blue and the other in brown according as an acid or a solution
of chloride have been caused to react upon the chemicals.
These impressions having a proto salt of iron and alkaline prussiate as their base
are invisible or nearly so until brought into contact with the chemicals employed to
take out the writing and are well fitted for paper for letters of credit and the like
which require to be damped for the copying press. The blue reaction is rendered
clearly visible oven by the action of weak acids such as citric acid, binoxalate
of potassium, bisulphite of soda and the like.
The application of acids forms prussian blue and produces blue stains on a cheque or
other document prepared according to this Invention.
Contact with decolourising chlorine compounds or chlorides produces dark or
brown stains of oxide of manganese.
The reaction of decolourising oxidising agents upon the organic bases or salts
derived from coal tar such as diphenylamine oxalate of aniline or salts of naphthyl-
amine produces peculiar dark or brown stains.
Contact with alkalies produces dark or brown stains of oxide of iron or oxide
of manganese.
Ferrocyanide of manganese in the form of a precipitate does not produce the same
result as the mixture of sulphate of manganese and soluble ferrocyanide ground
together in the colour being but slightly affected by acids in the same way as all
insoluble ferrocyanides in general in the presence of a proto salt of iron.
The printed cryptographic paper prepared as herein before described may be
employed with advantage for cheques, letters of credit or other monetary documents.
It is sufficient to print over the vignette of the cheque with any removeable colour or
preferably with a colour having soluble or insoluble ferro or ferri cyanide of
potassium as its base with or without admixture of diphenylamine or analogous
compound derived from coal tar with a view to rendering any alteration in the
writing still more difficult.
A colour of great sensitiveness is also produced by contact with the writing which
is fixed in such a manner that a ground or tint printed in parallel lines with this
mixture produces when written over with ordinary red ink for example, black lines at
the points of intersection of these ground lines and ordinary red lines at the places
where the pen passes over the parts not printed on with the sensitive colours.
This method of forming a sensitive tinted ground of lines on a cheque at the side of
or combined with the ordinary ground of parallel lines enables the total or figures to
be written or appear as if written in common black ink and also in red ink forming
red and black strokes affording the most perfect security against fraudulent alterations.
The colour producing this reaction is composed of pure lactate or sulphate of iron
dried and ground with fatty varnish on the one hand and of ferricyanide of potassium

page_text: likewise ground with fatty varnish. These two colours are mixed in about equal
proportions at the moment of using them.
Vignettes or designs for cheques may also be printed with a colour whose base
is dried sulphocyanide of lead and sulphate of copper as pure as possible to which
a salt of iron or a ferrocyanide may be added if desired. In all cases these sensitive
colours require to be ground separately with the fatty varnish and must not be
mixed until just before they are used. When these sensitive colours are employed it
sometimes happens that one of the reagents acts on the other in the course of
the treatment in which case the object is overreached. This results from the
employment of the inking rollers composed of glue and molasses such as are commonly
used in printing machines. This composition is injurious in this process owing
to the moisture which it contains and rubber or leather must be employed in the
construction of the inking rollers in order to ensure success.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. Preventing fraudulent alteration or falsification of cheques and other like
documents either by printing a ground or design with materials prepared with a base
of a proto salt of iron and a salt of manganese previously dried or by impregnating
the paper with the salts held in suspension in a suitable vehicle and applied by means
of a spray producer substantially as hereinbefore described and afterwards printing a
second ground applied over the first ground or on the impregnated paper with
materials having a base of an alkaline ferrocyanide with or without the addition
of diphenylamine, oxalate of aniline or a salt of a homologue of aniline or a pure salt
of naphthylamine in order to cause conspicuous blue, brown or dark stains to appear
when the paper is acted on by acids, alkalies, chlorides or the like substantially
as hereinbefore described.
2. Preventing the fraudulent alteration or falsification of cheques and the like
by the application of a fatty colour containing in a nascent condition all the elements
for the formation of Prussian blue the said colour being obtained by the employment
of two or more colours ground separately with salts of protoxide of iron on the one
part and ferricyanide of potassium on the other part with or without sulphate
of manganese and prepared in such a manner that a mixture of these colours contains
elements capable either of fixing the writing ink or producing a blue colour when
wetted either with water or with acids or of producing black marks at the places
where lines printed with this preparation are intersected by lines or strokes formed in
writing with red or other ink all substantially as herein before described.
3. The combination of means for preventing the falsification or fraudulent alteration
of cheques and the like substantially as hereinbefore described.
D L
1
T
1000
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