Improvements in Printing or Stamping Inks.
Year: 1890

page_text: ate of Application, 7th Oct., 1890-Accepted, 29th Nov., 1890
COMPLETE SPECIFICATION.
Improvements in Printing or Stamping Inks.
I, CHARLES MICHAEL HIGGINS of Brooklyn, in the County of Kings and State of
New York, Manufacturer, do hereby declare the nature of my invention for
PRINTING OR STAMPING INKS, and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement:-
My invention applies more especially to inks for type-writing, ticket-printing,
cash-registering or other small printing machines, as well as to hand-stamps of
rubber or metal where a non-drying ink is needed which will last indefinitely on
the pad, roller, ribbon or other inking device without hardening or drying
thereon, and always give a uniform impression whether in constant or occasional use.
Briefly stated, iny invention consists in an ink composed of oleic acid combined
with methyl violet or other colouring matter, as hereinafter set forth.
It is well known that most of the inks in present use for the purposes named are
composed of glycerine holding aniline colours in solution. Glycerine, however,
although one of the best known solvents for the aniline colours, and a non-dryer, is
yet open to the very serious objection that it is perfectly soluble in water, and very
susceptible to atmospheric moisture, so that the ink when on the printing device is
affected by the relative dryness or moisture of the air, which is a constant element of
irregularity in the inking and printing action, causing the ink to print too freely,
as it too much inked, on a moist day, and to print too feebly, as if insufficiently
inked, on a very dry day, which becomes quite objectionable in type-writing and
similar machines. Another serious objection is, that as both the vehicle and the
pigment of the ink are intensely soluble in water the ink does not dry or set quickly
on the paper, and will smudge or blur very easily in contact with any moisture, or
with the fingers of the manipulator.
These objections have recently created a strong demand for an ink which will
entirely dispense with the glycerine vehicle, or any vehicle soluble in water, or affected
by atmospheric moisture, and which will yet hold the colouring matter in absolute
solution. For this purpose it is therefore apparent that only a vehicle of a true oily
nature should be used, as oils are not affected by moisture, and this oil should hold
the colouring inatter in actual solution, and in large quantity.
Furthermore, this colouring matter should be a water colour, or soluble in water,
so that the ink when printed will admit of a good press copy, and as the aniline
colours are the most intense and brilliant known the ideal ink should be a non-
drying, oily vehicle holding an aniline or water-colour in actual solution.
Now it has been found extremely difficult to obtain an oily vehicle which would
dissolve an aniline or water-colour in any quantity fit for the purpose of such an
ink. Most all the ordinary or well known animal, vegetable and mineral oils will
not dissolve any of the aniline or soluble water-colours except to a very trifling
extent, like a mere stain. For example, olive, lard, paraffin, sperm, linseed cotton-
seed and a whole series of related oils have practically no solvent effect hot or
cold. Castor oil is a little better, but it is practically useless to form a solution of any
useful strength for the purpose.
I have discovered, however, that oleic acid, the basis of several of the animal
and vegetable oils, forms an extraordinary solvent for some of the aniline colours,
and particularly for the methyl violet, which is one of the strongest and most used of
these colours. Oleic acid forms, I find, a perfectly non-drying oily vehicle, very
limpid, smooth and unctuous, and perfectly adapted for the ideal vehicle. It will
dissolve from twenty to fifty per cent. of its own weight of methyl violet, forming a
fluid oily ink of great intensity of colour with which the inking roller, ribbon, pad, or
other inking device may be perfectly and uniformly saturated, and which will give off

page_text: the ink readily to types or stamps, and produce a clear and uniform impression on the
paper. This ink has a very even distributing quality, and never dries on the inking
device, and is entirely unaffected by the varying moisture in the air. It hence lasts
indefinitely on the roller after once inking, and prints very smoothly and uniformly
whether constantly or occasionally used, which has been the great desideratum hereto-
fore sought for. Furthermore, when printed on the paper the impression practically
dries or sets at once, and will bear immediate contact without blurring, which is a
most important advantage in type-writing and in stamping. As, however, the
colouring matter is entirely soluble in water a perfect press copy of the impression
may be obtained with the copying press in the usual manner. This copy will show
no tendency to blur or run, as is the case with glycerine inks, which is an
advantage.
This same ink may be used for rubber stamping, the felt or other inking pad
being saturated therewith, for which purpose it will be found much better and
cheaper than the glycerine inks, and will have no injurious action on the
stamps, provided the stamp is not allowed to remain in constant contact with the
inked pad.
In making my improved ink I use either crude or purified oleic acid, and stir
the colour into the same either in powder, lump or granular form, and leave the same
to dissolve, stirring occasionally until the solution is perfected. The oleic acid may
sometimes be heated to nearly the boiling point of water in a water or steam-jacketeri
kettle, and the colouring matter may then be introduced and dissolved in the hot oil,
which will make the solution a little better and more rapidly, but the solution can be
made nearly as well in the cold. I generally use one ounce avoirdupois of the
colouring mattor to four fluid ounces of the oleic acid, all of which will be dissolved,
but of course a greater or less quantity of the colour can be used according to the
strength of the ink desired. The saturating limit of the solution when made cold is
near to the specific proportion which I have mentioned, and in cases where a stronger
solution is required some alcohol may be added to the oleic acid, which will increase
the quantity of colour which can be held in solution. Or, in some cases, a strong or
a saturated solution of the colour can be made in alcohol, which can then be mixed in
any desired proportion with the saturated solution made in the oleic acid, which will
make an ink of greater colour strength than can be made with the oleic acid alone.
The alcohol will of course evaporate from the inking device, leaving the ink of heavier
body, but the oleic acid will keep it perfectly liquid and prevent drying. In some
cases one of the essential oils, preferably of the spices, such as cloves, cinnamon, or
allspice, can be nixed with the oleic acid in certain proportions, which will increase
the solubilities of some of the colours in the vehicle and also prevent rancidity in the
oleic acid.
The oleic acid has greater solvent power on methyl violet than any colour I have
yet found, but it will dissolve other colours in varying degrees, especially if from one
quarter to one half of its bulk of oil of cloves or cinnamon be mixed therewith.
Thus to produce a green ink, two parts of oleic acid and one part of oil of cloves
are mixed together and heated, and the green crystals, or aniline green, can then
be dissolved in the hot oils to the desired density. Or the green crystals can first be
dissolved in the oil of cloves, cold or hot, and the oleic acid afterwards added gradually,
and the whole intimately stirred together, which will form a liquid oily green ink of
great intensity. Soluble Prussian blue may be first moistened with a little sulphuric
acid, and can then be mixed with and dissolved in the oleic acid, preferably cold, forming
a permanent blue ink. Ultramarine blue will also form a very smooth or intimate
mixture with the oleic acid, almost, if not actually, dissolving therein, and forming
a bright blue permanent ink. Several other pigments or colouring matters may be
used in a similar way.
Another blue ink can be made by mixing the described aniline violet and green
inks together, the shade of blue depending upon the relative proportions of the
two inks.
Carbon may of course be incornorated with any of the int mixtures described

page_text: My improved ink may of course be also used for ordinary press printing, and
particularly as a copyable printing ink, for which it is specially adapted."
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim as my invention is :-
1. A stamping or printing ink composed of oleic acid and a dye-stuff or colouring
matter dissolved therein, substantially as herein set forth.
2. A printing or stamping ink composed of oleic acid and methyl violet dissolved
therein, substantially as herein set forth.
3. A printing or stamping ink composed of oleic acid, an essential oil and a colouring
matter dissolved in the same, substantially as herein set forth.
4. A copyable printing ink composed of oleic acid combined, with a colouring matter
soluble in water dissolved therein, substantially as herein set forth.
Dated this 11th day of September 1890
CHARLES MICHAEL HIGGINS.
W. P. Thompson & Boult,
Agents for the Applicant.
CHARLES MICHAEL HIGGINS.
W. P. Thompson & Boult,
Agents for the Applicant.