IMPROVEMENTS IN THE PREPARATION OF PIGMENTS
Year: 1866

page_text: LETTERS PATENT to Alfred Vincent Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Mechanical
Draughtsman, for the Invention of "IMPROVEMENTS IN THE PREPARATION
OF PIGMENTS."-A communication from abroad by Stuart Gwynn, of
the City of New York, in the United States of America.
Sealed the 27th February 1866, and dated the 3rd January 1866.
PROVISIONAL SPECIFICATION left by the said Alfred Vincent Newton
at the Office of the Commissioners of Patents, with his Petition, on
the 3rd January 1866.
I, ALFRED VINCENT NEWTON, of the Office for Patents, 66, Chancery
Lane, in the County of Middlesex, Mechanical Draughtsman, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE
PREPARATION OF PIGMENTS," to be as follows:-
The object of this Invention is to obtain opaque pigments by producing
in the normal pigments a structural change that will alter their mechanical
qualities and free them from gaseous and other impurities. The method
preferred of attaining this object is by first preparing a bath of oil, super-
heated steam, or other suitable fluid, in which the pigments to be treated
can be stirred and heated; while this heating and stirring is proceeding
(with the view of changing the atomic structure of the pigments) there

page_text: may be at the same time injected into them, if required, heated air, gases,
vapours, or fluids, as the nature of the crude or natural pigments require,
thus expelling or changing the nature of the gaseous and other impurities,
and bringing the atoms of the pigments into conditions that fit them for
the further operations necessary to render them opaque, in which state
they more readily mix and form chemical compounds with oils or other
vehicles. The required heat will vary with the pigment that is to be
prepared. Carmine requires the least, say 100° Fahrenheit, while some
require 1000° or more. Oxide of zinc, if heated much above 500°, rapidly
becomes yellow. The carbon colours require about 600°, sulphate and
carbonate of lead require about 800°, and the iron oxides and some other
metallic paints about 1000° or over. Practice will enable the expert, after
a few tests, to obtain with certainty the best results. The pigment is now
removed to a pneumatic, hydrostatic, or mechanical press, and subjected
to a concentrating power of from two to eight tons per inch of area.
This concentration is effected either in elastic bags or in very strong
cylindrical vessels, or by preference in open, ended steel tubes, out of which
the pigment will be discharged after the manner of maccaroni.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alfred Vincent Newton in the Great Seal Patent
Office on the 3rd July 1866.
TO ALL TO WHOM THESE PRESENTS, SHALL COME, I, ALFRED
VINCENT NEWTON, of..the Office for Patents, 66; Chancery Lane, in, the
County of Middlesex, Mechanical Draughtsman, send greeting.
11
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of January, in the year of our
Lord One thousand eight hundred and sixty-six, in the twenty-ninth year,
of Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Alfred Vincent Newton, Her special licence that I, the
said. Alfred Vincent Newton, my executors, administrators, and assigns, or
such others as I, the said Alfred Vincent Newton, my executors, adminis
trators, 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
1:
CIDS 1,
21
Hardy
.

page_text: .
of Man, an Invention for "IMPROVEMENTS IN THE PREPARATION OF PIGMENTS,"
being a communication from abroad, upon the condition (amongst others)
that I, the said Alfred Vincent Newton, my executors or administrators,
by an instrument in writing under my, or their; or one of their b
'hands' and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the sale was to be performed, and cause
tlie 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 Alfred Vincent Newton, 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)-
water.
The description of the Invention of "Improvements in the Preparation"
of Pigments," I will preface' by some' remarks on the experiments of my
correspondent, whereby he' was led to the improved manufacture of opaque
pigments. In One thousand eight hundred and sixty-three, at the request
of the then Secretary of the United States Treasury, he began an extended
series of experiments (at his own cost) with a view to improve the quality
of inks for plate printing in the Treasury' Issues Department. The first
work 'was a careful chemical and microscopic analysis of the pigments then
used as a basis for the inks. Up to this time the Chinese had produced'
the most brilliant and opaque pigments, and a close examination revealed
the cause of this superiority. It proved to be long continued grinding in
Like treatment produced in pigments of his make like results.
Thus the brilliancy and opacity of zinc, white prússian, blue chrome, and
other green and yellow pigments, vermillion, carmine, lampblack, and
other carbon' pigments, &c., were increased by this treatment. The next
enquiry' was, how does this structural change by grinding affect their rela-
tive gravity? To the surprise of the operator it was increased. Renewed
microscopic examinations with polarized light revealed how this seeming
anomaly could be reconciled with the fact: Pigments were examined,"
prepared by sublimation (such as zinc white)," precipitated by double"
decomposition (such as chrome colors and Prussian blue), by corrosion
(such as white leads), eliminated from the animal kingdom' (such" as""
carmine), and from inorganic matter (such as the aniline 'colors from coat'
tar, &c.) The experimenter now sought to make pigments as opaque' and
brilliant (as those obtained by long continued grinding) by chemical
manipulation. In this he only met a partial success. Boiling in acid's,"
alkalies,' and in solutions of neutral salts, oils, and in water under a vacuum,
12:1.90
C

page_text: &c., as the nature of the crude pigment admitted of gave only partial
results. Heat by water and steam baths, oil baths, metallic baths, in
furnaces and muffles, superheated steam (the latter up to one thousand
degrees of Fahrenheit), and finally up to the extreme heat obtained from
the oxyhydrogen blow pipe (this latter, of course, decomposing all but
the most refractory pigments) was tried, but no result was reached.equal
to grinding. Almost in despair of discovering a method of manufacture
suitable for large quantities of pigments, a series of experiments was
undertaken on condensation by combined chemical and mechanical con-
centration of the atoms composing the pigments in their raw or normal
state. The first results were not satisfactory, but samples obtained by
bringing into use machinery, apparatus, and manipulations based on estab-
lished facts (which had been used in preparing artificial fuels in England
in One thousand eight hundred and fifty-one and One thousand eight
hundred and fifty-two) determined the experimenter to persevere, and led
him ultimately to the most satisfactory results.
I will now proceed to describe the process which constitutes the subject
matter of the Invention communicated to me from abroad. I first prepare
a bath of oil or other suitable fluid (by and in proper apparatus). I prefer
superheated steam, in which I can stir and heat the pigments which are to
be rendered opaque (by a change of atomic structure), injecting into them
at the same time, if required, heated air, gases, vapors, or fluids, as the
nature of the crude or natural pigments require, thus expelling or changing
the nature of the gaseous and other impurities, and bringing the atoms of
the pigments into conditions that fit them for the further operations neces-
sary to render them opaque, in which state they more readily mix and
form chemical compounds with oils or other vehicles. The required heat
will vary with the pigment that is to be prepared; carmine requires the
least, say one hundred degrees Fahrenheit, while some require one thousand
degrees or more. Oxide of zinc I treat at about five hundred degrees; if
much above that it rapidly becomes yellow. The carbon colors requires
about six hundred degrees. Sulphate and carbonate of lead require about
eight hundred degrees, and the iron oxides and some other metallic paints
about one thousand degrees or over. Practice will enable the expert, after
a few tests, to obtain with certainty the best results. The pigment is now
removed to a pneumatic, hydrostatic, or mechanical press (I prefer the two
former), and subjected to a concentrating power of from two to eight tons
per inch of area. This concentration may be effected either in elastic bags
contained in suitable apparatus, or in very strong cylindrical vessels, or by

page_text: preference in open ended steel tubes, out of the open end of which the
pigment will be discharged after the manner of maccaroni.
Having now explained the nature of the improvements in the prepara-
tion of pigments, I wish it to be understood that under the above in part
recited Letters Patent I claim, producing in the normal pigments a struc-
tural change, thereby altering their mechanical qualities and freeing them
from gaseous and other impurities, by the means above described.
In witness whereof, I, the said Alfred Vincent Newton, have
hereunto set my hand and seal, the Third day of July, in the
year of our Lord One thousand eight hundred and sixty-six.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
A. V. NEWTON. (L.S.)