Process for Manufacturing Black Pigments from Carbonaceous Materials.
Year: 1897

page_text: Date of Application, 22nd Sept., 1897-Accepted, 4th Dec., 1897
COMPLETE SPECIFICATION.
Process for Manufacturing Black Pigments from Carbonaceous
Materials.
We RUDOLF STROBENTZ of No. 89 Üllöer Strasse Manufacturer and JOSEF FRIED of
No. 69 Üllöer Strasse Merchant, both of Budapest in the Kingdom of Hungary, do
hereby declare the nature of our said invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:
$
Black pigments have hitherto been produced by subjecting certain carbonaceous,
organic substances such as wood, brown coal, bones etc. to dry distillation and
pulverizing the residues, which process, in consequence of the consumption of fuel
and the loss of volatile bodies which escape during the distillation, is very expensive,
since the yield of pigments amounts to only 20-50% according to the quality of the
raw material. Even in this case, if the escaping gaseous products are collected,
condensed and utilized, the costs of manufacturing the pigments decrease only to a
small extent in consequence of the work and costs expended thereon and also on
account of the expensive manufacturing plant.
The essential and characteristic feature of our process is its great simplicity.
We obtain the whole of the treated raw material as black pigment of best
quality and hardly consume any fuel at all since the whole process is carried out
without the medium of heat and only a small quantity of fuel is necessary for drying
the finished goods; this consumption of fuel is however avoided in summer when we
may employ the heat of the sun as a drying means.
The reaction itself will only exceptionally be effected by heat.
Our Invention is based upon an observation which according to our knowledge is
neither known nor technically utilized.
It is, however, an undoubted fact that if certain kinds of brown coal preferably
lignites, pulverized as much as possible, are mixed with a solution of certain metallic
salts especially with the solution of ferrous sulphate, ferric chloride and the like and
preferably in such manner that the mixture forms a moist substance, the brown colour
of the coal disappears in a short time and becomes a pure black colour which is
durable even when dried at a high temperature. The cause of this reaction is that
the coal contains certain organic compounds which form black compounds with
metallic salts.
Now we have also made experiments to ascertain whether such coals or other
carbonaceous substances, which alone are not (or only to a small degree) adapted for
manufacturingpigments, could be prepared artificially in such manner that when
treated with metallic salts they may give useful pigments.
Our experiments have shown that these materials, especially such brown coals
which, with metallic salts do not produce pigments of a good quality, may be
employed for the above purpose when they are previously impregnated with certain
organic compounds for instance with those compounds which, with metallic salts,
give black precipitates namely tannic acid, gallic acid, pyrogallic acid and the like.
By this process we may also modify the tinge of the pigment.

page_text: The condition is that the coal or other primary substances employed is pulverizable
and possesses a large absorbing capacity.
In this case, the primary substance is pulverized or comminuted in any other
manner, then impregnated with the organic compound and finally treated with the
corresponding metallic salt.
The process, however, can also be carried out in reversed order of succession.
Under all circumstances, the chief condition is that the primary substance should
be pulverized to the necessary fineness before being treated with the metallic salts or
with the organic compounds and metallic salts.
By employing coarse substances the results are less satisfactory and the quality of
the product may be improved by subsequent grinding or comminuting.
Pigments manufactured according to our process may be substituted for the lamp
black and black pigments hitherto employed.
The quantity of the substance employed may be varied according to the quality of
the raw material. For instance when employing Hungarian lignites, a fine deep
black pigment may be obtained by using:-100 kilogrammes ferrous sulphate with
1000 kilogrammes of lignite, the former being dissolved in about 300 kilogrammes
of water and well mixed with the lignite. In like manner 100 kilogrammes ferric
chloride may be added to 1000 kilogrammes of lignite, which is likewise dissolved in
300 kilogrammes of water.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed, I declare that what I claim is :-
1. Process for manufacturing pigments from brown coal, carbonaceous and other
similar substances without burning or glowing same consisting in pulverizing the
said substances and mixing same in a suitable proportion with metallic salts preferably
with the sulphates or chlorides of iron substantially as described.
2. Process for manufacturing pigments from brown coal, carbonaceous and other
similar substances without burning or glowing same consisting in pulverizing the
said substances and treating same with certain organic compounds such as tannic
acid, gallic acid, pyrogallic acid or other analogous substances and with metallic salts
preferably with the sulphates or chlorides of iron substantially as described.
3. As a new article of manufacture a black pigment prepared from carbonaceous
materials without burning or glowing same substantially as described.
Date o
of September 1907.
PHILIP M. JUSTICE
Chartered Patent. Agent, London. For the Applicants.