Improvements in the Method of Printing Gold, Silver, or Platinum Decorations on Ceramic Articles.
Year: 1887

page_text: Improvements in the Method of Printing Gold, Silver, or Platinum
Decorations on Ceramic Articles.
We, MAX EHRLICH, Chemist and CARL STOROK, Merchant, both of 19 Bocken-
heimerlandstrasse at Frankfort on the Main in the German Empire 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 :-
Decorations in gold, silver and platinum on pottery and similar articles were
heretofore made by applying the merchantable liquid gold composition to the ceramic
ware by means of a feather or brush.
The exact proportion of the substances which this liquid is composed of and the
process by which it is produced are not known as it is kept secret by some laboratories
for refining metals, which, however sell this liquid composition everywhere.
After having applied the liquid to the article, the latter was burnt in an oven or
muffle.
As already told the decorations were heretofore made with a brush or feather, but
supposing now we desire to print any design, letters or the like in metalliferous colors
on the article, it will be necessary to use for instance a gold composition, which is not
so liquid as that described above and moreover the china must beforehand be treated
or coated with a lac or varnish, so that the tough gold composition, which can only be
used for printing, will stick firmly to it.
The gold composition used for printing purposes, may be obtained by the process
which is described in our British Application for Patent No. 9291 A.D. 1887 and
which for a better understanding of our invention we shall recapitulate in short
terms, viz. We take the merchantable liquid gold composition and precipitate by
means of ether the sulphuret of gold chemically combined with balsam of sulphur
contained in the composition. We gain a compound in the form of dust. This
compound we dissolve in nitrobenzole and receive a tough and gluey composition
being apt to be used as printing color.
Before applying the printing color to the article by the well known ways of
printing, reprinting or dusting, the article which is to be ornamented must be coated
with a lac or varnish, so that the golden printing color may stick to the ceramic
article. But the lacs generally employed by producing decorations on ceramic

page_text: articles cannot be used in this case, as all these compositions do not burn up without
leaving ashes. But this is the chief demand we must put to such a lac for golden
decorations on ceramic articles, since otherwise the golden decorations when burnt
will show blue or red margins. Henceforth it is absolutely necessary to use a lac or
varnish which burns up without leaving ashes and has great adhesive capacities, it
also must dry very fast.
For producing the lac we procede as follows: We take a volatile oil such as
turpentine or lavender-oil or the products of oxydation of these, that are resins, or a
fat oil, such as linseed oil or its products of oxydation and treat it with sulphur in
presence of heat. After this has been finished we put to it again a volatile oil such as
turpentine oil, or carburet of sulphur, ether, acetone, or other media which dissolve
resin and evaporate at the same time without residue.
This lac we apply to the pottery in an utmost thin coat and before getting dry we
lay albumenized paper upon which the golden decoration has been printed, to the
pottery surface, so that the gold decoration may stick on it, because it has been
provided with the above described lac. We subsequently wash-off this albumenized
paper whereby only the gold decoration remains on the article.
pottery is burnt and shows the gold decoration in a bright color.
When dried the
In the same manner printed silver or platinum decorations can be produced on
pottery.
In the following an example of the fabrication and application of this lac shall be
given.
7,865 kg. Venetian turpentine oil are mixed with 2,135 kg. sulphur and heated by
stirring up continually during two hours unto 200° C. If a drop of this so gained
material is dipped on a glass plate it must, after cooling, be of a brown, transparent
color.
To every one kg. of this material, being composed of balsam of sulphur,
5 kg. turpentine oil are added whereby this balsam is dissolved into a clear brown
liquor which can be cleaned by means of filtration.
This lac is then applied to the ceramic article in a very thin portion. As long as it
is glutinous it is able to keep the reprinting picture, (mock leaf-golden ornament)
which is on the glair paper, on the ceramic article. After the paper having been
resolved in water the mock leaf golden ornament remains on the ceramic article and
is then burnt in a muffle.
The volatile or fat oils which we preferably use for the production of our lac are the
following Turpentine-oil, lavender-oil, poppy-seed-oil.
The products of oxydation of these which we use likewise for the same purpose are,
viz. Venetian turpentine, French turpentine, pine or fir-resin and other resins
derived from plants.
The dissolving media, which we preferably use for the production of our lac are:
ether, carburet of sulphur, alcohole, turpentine-oil, lavender-oil etc.
The albumenized paper, which we preferably use for the printing process, must be
made of white of eggs, which is as free from salts and ashes as possible and we use
especially such paper, that has been coated with dialyzed white of eggs.
Should we however employ the common albumenized paper as it is brought to the
market it is necessary to make its injurious properties innoxious by coating it with a
solution of 1% collodium, caoutchouc or gutta-percha or similar dissolving matters.
By washing the albumenized paper off from the china all its salts etc. will also be
taken away.
Having now fully 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) The method of producing decorations on pottery and other articles, being
effectuated by first providing the article with a lac burning up without ashes and by
then applying a gold, silver or platinum colour to it by means of printing, before it
gets dry and finally by burning the article in a muffle or oven for the purpose as
described.

page_text: 2) The method of producing decorations in gold, silver, or platinum on pottery and
other articles, being effectuated by first providing the article with a lac being free
from all ashes when barnt, by then applying the gold decoration (or silver, or
platinum) to the article by way of reprinting from albumenized paper, coated with
dialyzed white of eggs, by washing off the paper and by finally burning the article in
a muffle or oven, for the purpose as described.
3) The method of producing decorations in gold, silver, or platinum on pottery and
other articles, being effectuated by first providing the article with a lac, being free
from all ashes when burnt, by then applying the gold decoration (or silver, or
platinum) to the article by way of reprinting from albumenized paper, coated with
collodium, caoutchouc or gutta-percha, by washing off the paper and by finally
burning the article in a muffle or oven, for the purpose as described.
4) The method of producing decorations in gold, silver, or platinum on pottery and
other articles, being effectuated by first providing the article with a lac, gained by
treating volatile or fat oils or their products of oxydation with sulphur in presence of
heat and by subsequently dissolving this compound in volatile or fat oils, or similar
resin-dissolving media, by then applying the gold decoration (silver, platinum) to the
article by way of printing or reprinting and by finally burning the article in a muffle
or oven, for the purpose as described.
Dated this 9th of December 1887.