Improvements in and relating to the Manufacture of Pigments or Paints.
Year: 1893

page_text: Date of Application, 9th May, 1893-Accepted, 10th June, 183
COME LEIE DIECIFICATION.
[Communicated from abroad by WILLIAM NELSON BLAKEMAN, Junior, of
No. 160, South 9th Avenue, in the City of Mount Vernon, County of
Westchester, and State of New York, United States of America, Stock
Broker.]
Improvements in and relating to the Manufacture of Pigments
or Paints.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents
45 Southampton Buildings, in the County of Middlesex, do hereby declare the
nature of this invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
The object of this invention is to produce a pigment or paint in which certain
reactions of its constituents which take place in the drying of the compound shall
be retarded or rendered comparatively slow while said constituents are in bulk or
not exposed to the air, but which reactions, when the paint is applied in the usual
manner in thin coats as with a brush, shall be very positive, effecting a rapid
absorption and fixation of carbon dioxide in situ and a consequent rapid drying on
exposure to the atmosphere.
This object I accomplish in the manner below described.
Most of the metallic and earthy oxides and salts when exposed to the atmosphere,
have a natural tendency to pass to carbonates, the state of greatest opacity and
insolubility. But this action is slow and feeble, and even then it may be neutralized
or cease altogether, in the process of induration.
My process of treating said oxides and salts, including the sub-carbonates, not
only prevents any interruption of the natural carbonating action of the atmosphere
but also excites, or stimulates, or adds to, such action, due to the addition to the
oxides or salts of chemical agents having a strong affinity for carbon dioxide, some
of which agents exercise this affinity in more than one state such as in salt, solution,
or a derivative from such salt. Thus, in my process when the material treated is
exposed to the air and applied as a paint, the process of conversion into the state of
carbonate will be accelerated and strengthened and the reaction will be carried on
by absorption and fixation of carbon dioxide throughout the mass of material until
the mass is completely carbonated. Some of the salts which may be employed to
produce carbonating action are such as borate of magnesia, monometa-borate of
soda, sulphate of magnesia, sulphate of alumina and alum.
In carrying out my process I may make the product or manufacture in the
commercial form of a "free dry pigment," or that of a "pigment ground in oil,"
or that of a "ready mixed paint.'
In preparing the material, oxide or salt, as a "free dry pigment," I thoroughly
incorporate therewith an agent or agents having a strong affinity for carbon dioxide
such as preferably, borate of maguesia or monometa-borate of soda; and if basic
acetate of lead be chosen as a pigment, the addition of ten to fifteen per cent. of
borate of magnesia will give good results, care being taken to exclude the air from
the mixture, as the affinity of this mixture for carbon-dioxide is great. If litharge
or protoxide of lead is chosen for a pigment one or two per cent. of normal or
neutral acetate of lead should be intimately ground with it, in addition to the
borate of magnesia or other agent having an affinity for carbon-dioxide. These
mixtures may be made, if desired, with the ingredients in a condition slightly moist
instead of perfectly dry. In the case of the two materials above mentioned selected
for pigments, the one (basic acetate of lead) is already basic to carbon dioxide
before the addition to it of the carbon-dioxide-absorbent, and the other (litharge)
will be changed into basic acetate of lead after the addition of the normal or

page_text: neutral acetate of lead. But in the case of selecting other oxides or salts as
materials for dry pigments, these may be first made basic to carbon dioxide by
incorporating with them a metallic soap such as hereinafter described for making
ready mixed paints, in which case the addition of the soap may be omitted in
making the mixed paints, or less soap used therefor. The addition of the soap to
the materials for dry pigments may be made thereto without essentially changing
the dry character of the same. If the salts of the alkaline earths be selected as
pigments better results will be obtained if used in the state of hydrates.
In preparing the material "ground in oil," a drying oil, but preferably a drying-
oil such as below described, may be added to the pigment to bring the whole to a
stiff and heavy paste.
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In preparing ready-mixed paints" I first take as a vehicle for mixture with the
pigment, preferably a drying-oil, and impart to it an alkaline or basic reaction by
dissolving in it, by the aid of heat if desired, a metallic soap preferably a metallic
soap having an affinity for carbon-dioxide, such as alumina-soap. The application
of heat will hasten the amalgamation of the soap with the oil and other ingredients
used. To the oil thus treated I then add a salt or salts capable of absorbing carbon
dioxide, such as monometa-berate of soda borate of magnesia, or sulphate of
magnesia, and after thoroughly commingling one or all of them with the oil, I then
thoroughly mix into the oil any of the oxides and salts above nained which it may
be desired to use as a pigment, and when this mixture is spread or exposed to the
atmosphere, as in the art of painting, the carbonating reaction set up is rapidly
carried on by absorption and transmission through the mass till the whole is
carbonated.
If, therefore, in the making of the paint, the material used as the pigment be
highly sensitive to the absorption of carbon dioxide, it may be combined with a
neutral liquid vehicle; or if the liquid vehicle be basic, and highly sensitive to the
absorption of carbon dioxide it may be combined with a neutral pigment, or both
the pigment and liquid vehicle may be combined if each be basic, and highly
sensitive, to carbon dioxide. If either one be highly and the other feebly basic,
and sensitive, to carbon dioxide, the liquid vehicle and the pigment may be
combined into a paint, if, in any case, the reaction, alkaline or basic to carbon
dioxide, be strong enough to absorb and fix carbon dioxide until the whole covering,
mass, or coat of paint, is carbonated in situ by which absorption of carbon dioxide
the rapid drying of the paint is effected. I do not confine myself to the progressive
steps here named as they may be varied with good results, but as the object is the
absorption and fixation of carbon dioxide as rapidly as possible I have found the
best results are given when the vehicle is made thoroughly alkaline or basic at
first.
If the pigment has been prepared previously, as a "free dry pigment"
as above described, the presence in the oil of more of the same carbonating agent,
or another agent having an affinity for carbon dioxide, will not interfere with the
desired result, after mixture with the oil.
In all three forms as dry pigments, or ground in oil or mixed paints, the product
for commercial use should be put up in kegs, cans or cases, comparatively air-tight
in construction, in order to retard the setting up of carbonating reactions between
the ingredients until they are applied as a paint, when such actions will be rapid
in situ.
If litharge is used as a pigment one or two per cent. of normal or neutral acetate
of lead should be ground with it and when this mixture is made into a paint and
the paint is applied and exposed to the atmosphere there will be set in operation a
progressive formation of basic acetate of lead, and its successive decomposition by
carbon dioxide until the entire mass is carbonated throughout.
In carrying out my process, I do not confine myself to fixed proportions of the
materials above named, owing to the variety of the substances available for
pigments to which it may be applied as well as to the diversity in density of the
fiquid vehicles which may be employed and diverse activity of the carbonating
agents. But if basic acetate of lead be selected as the pigment to be subjected to

page_text: my process and oil as the liquid vehicle for the same, the several proportions of
elements which will give satisfactory results are as follows: From five to eight
per cent. of metallic soap to the oil used; from 100 to 150 per cent. of the lead
acetate to the oil; and from ten to fifteen per cent. of horate of magnesia to the
lead acetate. As basic acetate of lead when mixed with the oil will give an
alkaline or basic reaction to the oil, the metallic soap may be dispensed with, and
the acetate of lead when thus used as the pigment will then act in the double
capacity of effecting an alkaline or basic reaction in the oil and also as the
pigment. But the use of the metallic soap in addition is advantageous in making
the carbonating reactions or process cumulative.
By this invention a pure white paint can not only be made and laid on its
original whiteness, but it will also dry perfectly white. Where special colour
is desired, not inherent in the pigment used, of course any neutral, or other,
colouring agent or process, may be used which will not destroy the carbonating
drying action in the paint when laid on any surface by brush or in any other usual
manner.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. The hereinbefore described process of making carbonates for pigments or
paints which consists in combining with metallic and earthy oxides, acetates,
hydrates and sub-carbonates basic to carbon dioxide, salts capable of absorbing
carbon dioxide when the pigments are applied as paints.
2. The hereinbefore described process of converting metallic and earthy oxides,
acetates, hydrates and sub-carbonates into carbonates for paints, which consists in
mixing with the same, a liquid-vehicle capable of absorbing carbon dioxide, and
salts also capable of absorbing carbon dioxide.
3. As a new article of manufacture for a pigment or paint, a compound or
mixture of a metallic oxide and a metallic salt, one or both, and a salt capable of
absorbing carbon dioxide, the whole ground or powdered into intimate mixture,
with or without the addition of moisture, in the manner set forth.
Dated this 9th day of Mon 1802
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.