Improvements in the Manufacture of Stereotypes.
Year: 1894

page_text: Date of Application, 14th June, 1894
Complete Specification Left, 14th Mar., 1895-Accepted, 20th Apr., 1895
PROVISIONAL OF POTE
Improvements in the Manufacture of Stereotypes.
I, VICTOR LÖWENDAHL, of 8ª, Karduansmakaregatan, Stockholm, Sweden,
Electrician, do hereby declare the nature of this invention to be as follows:-
This invention relates to an improved method of manufacturing cheaply and in
a simple manner stereotypes, suitable for printing.
The method consists, essentially, in bringing the raised or embossed portions of
the block, form or pattern, a stereotype of which is to be produced, into contact
with the surface of a molten metal, alloy, or other suitable melted substance (wax
for instance) in such a manner that it adheres to these raised or embossed portions
and is lifted with them, when the form or pattern is removed from the melted
substance; the adhering portion of the metal, or other substance after being cooled
and separated from the block or form, constitutes a stereotype, the printing-surface
of which will consist of elevated and depressed portions exactly corresponding to
the original form or pattern. It is evident that the portions of the block or form
to which the metal is to adhere must be perfectly clean.
The process, as above described, is exceedingly simple, when the raised or
embossed portions of the form are of such a height that they may be brought into
contact with the molten metal, without the latter touching the depressed portions
of the form. On the other hand, when a stereotype is to be made from a drawing,
for instance, the case is different. It is then necessary to prepare the drawing in
such a manner, that the portions which are to be raised or embossed on the type
may obtain a surface, to which the molten metal will adhere, while to the other
portions of the drawing is given a surface to which this metal does not cling.
This may be accomplished in the following manner:-Let us assume that a
stereotype is to be produced, for example, from a pencil-drawing. The drawing
is, in the first place, executed on a suitable material, of which several different
kinds may be used; all of these, however, must possess the following characteristic
features, viz. that their surface shall neither be affected by the electrolytic liquid
into which the material is submerged during the treatment, nor be injured by
contact with the molten type-metal or other substance.
It has been found that a sheet of aluminium, the surface of which has been
previously ground smooth with emery or other grinding material, so as to be fine-
grained and consequently suitable for receiving the pencil-drawing may be
advantageously employed for this purpose. This surface is then treated with
hydrate of soda and afterwards with nitric acid, whereby it becomes almost white
and acquires the property that a metal cannot or can only with great difficulty be
deposited electrically on its surface.
On this surface the drawing is made with a pencil, and the material is then
treated in a galvanic bath, whereby the portious of the drawing formed by the
pencil strokes are coated with a metallic deposit, which is not formed on the other
portions of the surface. When the coating of precipitated metal has been thus
formed on the drawing, the metallized parts of the latter are thoroughly cleaned,.
and the plate, with the treated surface down, is brought into contact with the
molten metal, which must be easy to melt and for this reason may advantageously
consist of an alloy of tin, lead and bismuth. When they come into contact, a
soldering action takes place, which forms an important feature in the process.
The type-metal becomes soldered to the metallized parts, not to the other parts of

page_text: the aluminium-plate, however, and consequently, when the latter is lifted, the
type-metal adhering to the metallized parts will be lifted also, so that the printing
surface of the stereotype will be of the desired shape. When the aluminium plate
has thus been lifted to a suitable height, the melted mass is cooled off, and the
stereotype is carefully separated or broken off from the plate; the metallized
drawing, being soldered to the type-metal, will thus be fixed to the stereotype, and
form the printing surface of the latter. Thus the stereotype will consist of
elevated portions, corresponding to the drawing and, between these, depressions
which failed to adhere to the non-metallized parts of the plate, and consequently
were not lifted with the plate. It is evident that the same result may be attained
by allowing the plate to occupy a fixed horizontal position, and bringing the
surface of the molten metal into contact with it from below, the mass of molten
metal being subsequently lowered.
In case the drawing contains large, enclosed and smooth sections, the outer
atmospheric pressure will prevent the formation of the depressions in the stereotype
corresponding to these sections, and therefore the process must, under such
circumstances, be carried out in a partial vacuum.
According to another method of proceeding in such cases, although not equally
advantageous, the surface of the plate is coated with paraffin, volatile oil, water or
some other substance, that will vaporize by contact with the hot type-metal and
thereby favor the formation of the desired depressions, or, there may be mixed
into the molten mass some substance that will generate gases, as is the case with
mercury, for instance.
From what has been said above, it is apparent that the most important of the
operations enumerated here is the production of the stereotype by raising the
type-metal at certain parts corresponding to the block or form. The method of
producing the metallized block or form, on the other hand, is of minor importance,
inasmuch as this result may be produced by various processes.
Dated this 14th day of T1004
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.
1, VICTOR LÖWENDAHL, of 84 Karduansmakaregatan, Stockholm, Sweden,
Electrician, 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 :-
This invention relates to an improved method of manufacturing cheaply and in
a simple manner stereotypes, suitable for printing.
The method consists, essentially, in bringing the raised or embossed portions of
the block, form or pattern, of which a stereotype is to be produced, into contact with
the surface of a molten metal, alloy, or other suitable melted substance (wax for
instance) in such a manner that the molten substance adheres to these raised or
embossed portions and is lifted with them, when the form or pattern is removed
from the melted substance; the adhering portion of the melted, or other substance,
after being cooled and separated from the block or form, constitutes a stereotype,
the printing-surface of which will consist of elevated and depressed portions exactly
corresponding to the original form or pattern. It is evident that the portions of
the block or form to which the metal is to adhere must be perfectly clean.
The process, as above described, is exceedingly simple, when the raised or
embossed portions of the form are of such a height that they may be brought into

page_text: contact with the molten metal, without the latter touching the depressed portions
of the form. On the other hand, when a stereotype is to be made from a drawing,
for instance, the case is different. It is then necessary to prepare the drawing in
such a manner, that the portions which are to be raised or embossed on the type may
obtain a surface, to which the molten metal will adhere, while to the other portions
of the drawing is given a surface to which this metal does not cling. This may be
accomplished in the following mauner. Assuming that a stereotype is to be
produced, for example, from a pencil-drawing, the drawing is, in the first place,
executed on a suitable material, of which several different kinds may be used, all
of these, however, must possess the characteristic that their surface shall neither
be affected by the electrolytic liquid into which the material is submerged during the
treatment, nor be injured by contact with the molten type-metal or other substance.
It has been found that a sheet of aluminium, the surface of which has been
previously ground smooth with emery or other grinding material, so as to be
fine-grained and consequently suitable for receiving the pencil-drawing may be
advantageously employed for this purpose. This surface is then treated with
hydrate of soda and afterwards with nitric acid, whereby it becomes almost white
and acquires the property that a metal cannot or can only with great difficulty be
deposited electrically on its surface.
On this surface the drawing is made with a pencil, and the material is then
treated in a galvanic bath, whereby the portions of the drawing formed by the
pencil strokes are coated with a metallic deposit, which is not formed on the other
portions of the surface. When the coating of precipitated metal has been thus
formed on the drawing, the metallized parts of the latter are thoroughly cleaned,
and the plate, with the treated surface down, is brought into contact with the molten
metal, which must be easy to melt and for this reason may advantageously consist
of an alloy of tin, lead and bismuth. When they come into contact, a soldering
action takes place, which forms an important feature in the process. The type-
metal becomes soldered to the metallized parts, not to the other parts of the
aluminium-plate, however, and consequently, when the latter is lifted, the type-metal
adhering to the metallized parts will be lifted also, so that the printing surface of
the stereotype will be of the desired shape. When the aluminium plate has thus
been lifted to a suitable height, the melted mass is cooled off, and the stereotype is
carefully separated or broken off from the plate, the metallized drawing, being
soldered to the type-metal, will remain fixed to the stereotype, and form the
printing surface of the latter. Thus the stereotype will consist of elevated portions,
corresponding to the drawing and, between these, depressions which failed to adhere
to the non-metallized parts of the plate, and consequently were not lifted with the
plate. It is evident that the same result may be attained by allowing the plate to
occupy a fixed horizontal position, and bringing the surface of the molten metal
into contact with it from below, the mass of molten metal being subsequently
lowered.
In case the drawing contains large, enclosed and smooth sections, the outer
atmospheric pressure will prevent the formation of the depressions in the stereotype
corresponding to these sections, and therefore the process must, under such
circumstances, be carried out in a partial vacuum.
According to another method of proceeding in such cases, although not equally
advantageous, the surface of the plate is coated with paraffin, volatile oil, water or
some other substance, that will vaporize by contact with the hot type-metal and
thereby favor the formation of the desired depressions, or, there may be mixed into
the molten mass some substance that will generate gases, as is the case with mercury,
for instance.
From the foregoing description it is evident that the most important of the
operations above enumerated is the production of the stereotype by raising the
type-metal at certain parts corresponding to the block or form. The method of
producing the metallized block or form, on the other hand, is of minor importance,
inasmuch as this result may be produced by various processes.

page_text: Having now particularly 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 :-
:-
1st. The manufacture of stereotypes suitable for printing, by bringing the surface
of a molten substance into contact with a block, form or pattern, so constituted that
the molten substance can adhere to the embossed portions of the same, separating
this form or pattern and the molten mass in such a manner that the parts of the
substance that adhere to the form or pattern will be elevated although remaining
attached to the remainder of the substance, and then cooling off the substance and
removing the form or pattern.
2nd. The herein described method of preparing forms or patterns wherein the
parts that are to constitute the printing surface on the stereotype, are nearly in
the same plane with the other or non-essential portions, so that they may be treated
by the process herein described, the said method, consisting in making the
non-essential portions of, or covering them with, a substance to which the molten
mass will not adhere.
3rd. The herein described method of manufacturing a stereotype, consisting
in first depositing metal on certain parts of a suitable plate, then bringing such
parts into contact with a bath of molten metal to which the said parts become
soldered, then slightly raising the plate, cooling the molten metal and separating
the said plate from the metallic deposit which remains on the stereotype and
forms the printing surface thereof, substantially as hereinbefore described.
4th. A stereotype suitable for printing purposes, manufactured substantially as
hereinbefore described.
Dated the 14th day of Mah 1005
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.