Improvements in the Preparation of Aluminium and other Metal Plates for Planographic and other Printing Purposes.
Year: 1899

page_text: Date of Application, 12th May, 1899
Complete Specification Left, 12th Mar., 1900-Accepted, 5th May, 1900
PROVISIONAL SITU
Improvements in the Preparation of Aluminium and other Metal
Plates for Planographic and other Printing Purposes.
I, GUSTAV HENRY BLOCK, of 9, May Street, Beverley Road, Hull, in the
ounty of York, Lithographer, do hereby declare the nature of this invention
o be as follows:-
:-
My invention has for its object to provide aluminium or other metal plates
with a surface of a strong adhering precipitate of a crystalline nature, fromi
solutions of aluminium salts, zine salts or other metallic salts by simple immer-
sion, with or without the aid of a battery or a gentle electric current from a
dynamo, for the purpose of rendering such surfaces suitable for having designs
drawn upon or transferred on to them and printed therefrom after the manner
of lithography or otherwise.
According to my invention an aluminium or other plate to be prepared, is
first cleaned by using snake stone and water in the usual manner as in litho-
graphy, for the purpose of levelling all uneven particles adhering to the surface
and removing defects on or in the surface of the plate, and then I scour the
plate preferably with fine emery powder, felt and water, to produce a slight
roughness on the plate but without scratching the same.
I next dissolve 750 grammes of acid sulphate of aluminium, in 10 litres of
water and add 1 litre of nitric acid and I pour this solution into a vessel or
trough which contains a carbon anode and a cleaned aluminium plate which
together form an electric couple, whereby a gentle current is generated and a
precipitate is formed on the plate by immersion from 4 to 8 hours.
To obtain a precipitate on zinc or metal plates other than aluminium in the
same manner above indicated it is necessary to reduce the nitric acid to a
third of the above mentioned quantity and to reduce the period of immersion
to 45 minutes to one hour.
To expedite the process of precipitation I sometimes use an electric current
obtained from a Bunsen or other battery or from a dynamo. When I use a
Bunsen battery I connect the carbon anode in the trough with the copper (+)
of the said battery, the aluminium plate, which serves as the cathode to receive
the precipitate, being connected with the zine (-) of the battery. If desired
I may substitute a sheet of aluminium for the carbon anode. The time neces-
sary for precipitation is, in the case of aluminium from three to six hours
according to the thickness of layer required; for zinc or metal plates other
than aluminium a half hour the quantity of nitric acid being reduced to one
third as before. When the aluminium or other metal plate has received a suffi-
cient precipitate, it is taken out of the trough and rinsed well with water to
remove any loose particles. The plate is then sponged over with a mixture o
carbonate of magnesia, water and methylated spirit in the form of a paste, t
cleanse it and also to neutralise any acid matters adhering to its crystalline surfac
40 and, after being well rinsed with water, is dried and ready for receiving.
transfer

page_text: Instead of using the method before described I sometimes precipitate, by
gentle electric current, aluminium salt, zinc salt or other suitable metallic salt,
in solution with water and suitable acids, upon aluminium or other. metal
plates, to form a crystalline surface for my purpose.
Also I obtain a good precipitate on aluminium plates if I fill the precipitation
trough with a solution having advantageously, but not necessarily the following
proportions viz. :—
750 grammes of acid sulphate of aluminium A L (SO4)3
750 grammes of potassium alum A. L K (SO), dissolved in 20 litres of water.
1 litre of nitric acid, and
½ litre of phosphoric acid the mixture being well stirred before this latter
is added. The carbon and aluminium plate are connected together or to a
battery or dynamo electric machine, as herein before described.
When zinc or metal plates other than aluminium are to be prepared with a
precipitate of the same nature as the last mentioned solution the quantities of
acids used are to be reduced to about one third of those given.
The methods and processes herein before described refer mainly to the prepara-
tion of smooth aluminium or other metal plates, for the reception for pen and
ink drawings, transfers or photographic reproductions. To obtain ordinary
grain plates for chalk work, the aluminium or other metal plates are subjected
to sandblast as follows:-After an aluminium or other metal plate has been
previously cleaned as described, and dried, it is subjected to the sandblast and
the various grades of grain are regulated by the selection of fine or coarse sand
or such like material. After this operation is completed the plate well rinsed
with water to remove the fine dust of sand or metal and is then immersed in
one of the solutions and treated as herein before described.
In practice I prefer after treating zinc or other metal plates as herein before
described, to give them a second treatment to improve the appearance by making
them of a lighter color. For this second treatment I use a specially constructed
rocking bath, the four sides of which are in practice about 10 to 12 inches high,
and are covered on the inside with carbon plates or aluminium sheeting to
act as an anode and connected with the (+) positive pole of the battery. When
one or other of the solutions described with acids suitably reduced are placed
in this rocking bath and the zinc or other metal plate is immersed in this bath
and connected with the (-) negative pole of the battery, a current passes
through the solution and fixes a corresponding precipitate of the solution used
on the metal plate. The carbon or aluminium sheet lining is in practice pre-
ferably from 8 to 10 inches wide and kept about inches away from the bottom
of the rocking bath so as not to come into direct contact with the plate which
is to receive the precipitate. The liquid in the rocking bath should be of
such quantity as to allow the zinc and other metal plate to be well covered
in all parts when rocking.
During the treatment the rocking bath is kept in motion and as a dark film
appears on the surface of plate, it is sponged away while the plate is still in the
bath, this operation being repeated until the film which forms is less dark and
the plate assumes a lighter color. A new and strong precipitate is fixed to the
surface by this method. The plate is now disconnected from the (-) negative
pole of the battery and well rinsed with water and sponged over to remove any
loose particles and treated with the carbonate of magnesia and water and methy-
lated spirits as before described.
To produce stipple, grain, lines or the like by the above methods and processes
on aluminium, zinc or other metal plates I prefer to adopt the treatment
described in the Specification of my former Patent No. 2907/94, that is to say,
an aluminium plate is cleaned in a manner as before described and then the
grain, stipple or linework or the like is transferred to the plate in the usual
manner by lithography, photography or otherwise from a previous or permanent
original. Inext roll up this transfer with a suitable acid proof composition,

page_text: and further I dust in the transfer with dusting powder of a strong acid resisting
capacity such as a lead compound. The plate is then etched in the manner
of glass etching, the design of stipple, grain, lines or the like being brought
out in relief to the required depth. The etching being completed I remove
the acid proof composition and dusting powder with an alkaline, or other
suitable solution, which operation also destroys the grease contained in the
After rinsing the plate well
design of the grain, stipple, lines or the like.
with water, it is dried and slightly sandblasted with very fine sand, whereby the
flat tops of the stipple, grain, lines or the like are slightly roughened and afford
a firmer hold for the precipitate and render litho crayon work easier when draw-
ing upon the surface of an aluminium plate. The precipitate is fixed by any of
the methods or processes previously described and an aluminium plate is treated
with carbonate of magnesia also as described before.
To produce stipple grain or lines or the like on zine plates or other metal
plates I commence by cleaning the surfaces of the plates exactly as described in
the Complete Specification of my former Patent No. 2907/94 up to page 2 line 3.
The surface of the plate thus cleaned is then ready to receive the precipitate and
then I proceed according to either of the different methods or processes herein-
before described using the second treatment for giving the plates a light colour
followed by the treatment with carbonate of magnesia, water and methylated
spirits.
A tenacious film of precipitation on a smooth or grained aluminium plate
previously cleaned and prepared may be obtained, by simple immersion in a
trough containing one or other of the solutions without the aid of any battery
or electric current, naturally a longer time is required for the precipitation say
from 8 to 12 hours according to the thickness of film required.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London,
Agents for the Applicant.
Improvements in the Preparation of Aluminium and other Metal
Plates for Planographic and other Printing Purposes.
I, GUSTAV HENRY BLOCK, of 9, May Street, Beverley Road, Hull, in the
County of York, Lithographer, 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:-
My invention has for its object to provide aluminium or other metal plates
with a surface of a strong adhering precipitate of a crystalline nature, from
solutions of aluminium salts, zinc salts and other metallic salts by simple immer-
sion, with or without the aid of a battery or a gentle electric current from a
dynamo, for the purpose of rendering such surface suitable for having designs
drawn upon or transferred on to them and printed therefrom after the manner
of lithography or otherwise.
According to my invention an aluminium or other metal plate to be prepared, is
first cleaned by using snake stone and water in the usual manner as in litho-
graphy, for the purpose of levelling all uneven particles adhering to the surface
and removing defects on or in the surface of the plate, and then I scour the
plate preferably with fine emery powder, felt and water, to produce a slight
roughness on the plate but without scratching the same.

page_text: I next dissolve 750 grammes of sulphate of aluminium, in 10 litres of water.
and add 1 litre of nitric acid and I pour this solution into an oblong vessel or
trough which contains a carbon anode and a cleaned aluminium plate which
together form an electric couple, whereby a gentle current is generated and a
precipitate is formed on the plate by immersion from 4 to 8 hours.
To obtain a precipitate on zinc or metal plates other than aluminium in the
same manner above indicated it is necessary to reduce the nitric acid. to a
third of the above mentioned quantity and to reduce the period of immersion
to 45 minutes to one hour.
To expedite the process of precipitation I sometimes use an electric current
obtained from a Bunsen or other battery or from a dynamo. When use a
Bunsen battery I connect the carbon anode in the trough with the copper (+)
of the said battery, the aluminium plate, which serves as the cathode to receive
the precipitate, being connected with the zinc (-) of the battery. If desired
I may substitute a sheet of aluminium for the carbon anode. The time neces-
sary for precipitation is, in the case of aluminium from three to six hours
according to the thickness of layer required; for zine or metal plates other
than aluminium a half hour the quantity of nitric acid being reduced to one
third as before. When the aluminium or other metal plate has received a suffi-
cient precipitate, it is taken out of the trough and rinsed well with water to
remove any loose particles. The plate is then sponged over with a mixture of
carbonate of magnesia, water and methylated spirit in the form of a paste, to
cleanse it and also to neutralise any acid matters adhering to its crystalline surface
and, after being well rinsed and sponged with water, is dried and ready for
receiving a drawing or transfer.
:
Instead of using the method before mentioned I sometimes precipitate, by
gentle electric current, aluminium salts, zinc salts or other suitable metallic salts
in solution with water and suitable acids, upon aluminium or other metal
plates, to form a crystalline surface for my purpose.
Also I obtain a good precipitate on aluminium plates if I fill the precipitation
trough with a solution having advantageously, but not necessarily the following
proportions viz.:.
750 grammes of sulphate of aluminium Al, (804)
750 grammes of potassium alum A L K (SO), dissolved in 20 litres of water
adding
1 litre of nitric acid,, and
½ litre of phosphoric acid the mixture being, well stirred before this latter
is added. The carbon and aluminium are connected together or to ก
battery or dynamo electric machine, as herein before described.
When zinc or metal plates other than aluminium are to be prepared with a
precipitate of the same nature as the last mentioned solution the quantities of
acids used are to be reduced to about one third of those given.
The methods and processes herein before described refer mainly to the prepara-
tion of smooth aluminium or other metal plates, for the reception for pen and
ink drawings, transfers or photographic reproduction. To obtain ordinary
grain plates for chalk work, the aluminium or other metal plates are subjected
to sandblast as follows:-After the aluminium or other metal plate has been
previously cleaned as described, and dried, it is subjected to the sandblast and
the various grades of grain are regulated by the selection of fine or coarse sand
or such like material. After this operation is completed the plate is well rinsed
with water to remove the fine dust of sand or metal and is then immersed in
one of the solutions and treated as hereinbefore described..
In practice I prefer after treating zinc or other metal plates as hereinbefore
described, to give them a second treatment to improve the appearance by making
them of a lighter color. For this second treatment I use a specially constructed
rocking bath, the four sides of which are in practice about 10 to 12 inches high..
and are lined on the inside with carbon plates or aluminium sheeting to

page_text: et as an anode and connected with the (+) positive pole of the battery.
e or other of the solutions described with acids suitably reduced are placed
this rocking bath and the zinc or other metal plate is immersed in this bath
nd connected with the (-) negative pole of the battery, a current passes
arough the solution and fixes a corresponding precipitate of the solution used
n the metal plate. The carbon or aluminium sheet lining is in practice pre-
erably from to 10 inches wide and kept about 2 inches away from the bottom
f the rocking bath so as not to come into direct contact with the plate which
s to receive the precipitate. The liquid in the rocking bath should be of
uch quantity as to allow the zinc and other metal plate to be well covered
n all parts when rocking.
During the treatment the rocking bath is kept in motion and as a dark film
ppears on the surface of the plate, it is sponged away while the plate is still in the
ath, this operation being repeated until the film which forms is less dark and the
late assumes a lighter colour. The plate is now disconnected from the (-) nega-
live pole of the battery and well rinsed with water and sponged over to remove any
loose particles and treated with carbonate of magnesia and water and methy-
lated spirits as before described.
To produce stipple, grain lines or the like by the above methods or processes
prefer to adopt the treatment
on aluminium, zinc or other metal plates
described in the Specification of my former Patent No. 2907 of 1894, that is to say,
an aluminium plate is cleaned in the manner before described and then the
grain, stipple or linework or the like is transferred to the plate in the usual
manner by lithography, photography or otherwise from a previous or permanent
original. I next roll up this transfer with a suitable acid proof composition, and
further I dust in the transfer with dusting powder of a strong acid resisting capa-
city such as a lead compound. The aluminium plate is then etched in the manner
of glass etching, the design of stipple, grain, lines or the like being brought
out in relief to the required depth. The etching being completed I remove
the acid proof composition and dusting powder with an alkaline, or other
suitable solution, which operation also destroys the grease contained in the
design of the grain, stipple, lines or the like. After rinsing the plate well with
water, it is dried and slightly sandblasted with very fine sand, whereby the
tops of the stipple, grain, lines or the like are slightly roughened and afford
a firmer hold for the precipitate and render litho crayon work easier when draw-
ing upon the surface of an aluminium plate. The precipitate is fixed by any of
the methods or processes previously described and an aluminium plate is treated
with carbonate of magnesia also as described.
To produce stipple grain, lines or the like on zinc plates or other metal plates I
commence by cleaning the surfaces of the plates exactly as described in the Speci-
fication of my former Patent No. 2907 of 1894. The surface of the plate thus
cleaned is then ready to receive the precipitate and then I proceed according to
either of the different methods or processes hereinbefore described using the second
treatment for giving the plates a light colour followed by the treatment with
5 carbonate of magnesia, water and methylated spirit.
A tenacious film of precipitation on a smooth or grained aluminium plate
previously cleaned and prepared may be obtained, by simple immersion in a
trough containing one or other of the solutions without the aid of any battery or
electric current: naturally a longer time is required for the precipitation say
from 8 to 12 hours according to the thickness of film required.
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:
1. The process of preparing an aluminium or other metal plate for printing
purposes consisting in first cleaning the said plate, then roughening the surface
of the same,
then immersing it in a solution of sulphate of aluminium in water

page_text: to which a small quantity of nitric acid is added and then subjecting the plate
to the action of an electric current and finally treating the plate with a mixture
of carbonate of magnesia, water and methylated spirit in the form of a paste, all
substantially as, and for the purpose described.
2. The process of preparing an aluminium plate for printing purposes consisting
in first cleaning the said plate with snake stone and water in the usual manner,
then scouring the said plate with fine emery powder, and water to- slightly
roughen the same, then immersing the said plate for from 4 to 8 hours in
a solution of 750 grammes of sulphate of aluminium in 10 litres of water and 1
litre of nitric acid in the presence of a carbon plate which with the aluminium
plate, will form an electric couple (or, if desired, connecting the said carbon
and aluminium plates with a battery or other generator of electricity) and then
sponging over the plate with a mixture of carbonate of magnesia, water and
methylated spirit in the form of a paste all substantially as, and for the purpose,
described.
3. The process of preparing metal plates for printing purposes consisting in
precipitating aluminium salts, zinc salts or other metallic salts in solution with
water and suitable acids, by means of a gentle electric current, substantially as
described.
4. The process of preparing an aluminium plate for printing purposes, the
said plate having been suitably cleaned and roughened as hereinbefore described,
consisting in subjecting the said plate to electrolytic action in a solution of
sulphate of aluminium, potassium-alum, water, nitric acid and phosphoric acid,
substantially as described.
5. The method of preparing smooth or grain and stipple surfaces on aluminium
or other metal plates suitable for the reception of pen and ink drawings, transfers
or photographic reproductions or chalk drawings, consisting in subjecting the
metal plate previously cleaned and dried to a sand blast regulated according
to the grain desired and then subjecting the said plate, after it has been well
rinsed, to electrolytic acid for forming a precipitate upon its surface, substantially
as described.
6. In the preparation of metallic plates for printing purposes by either of the
processes herein before described, the treatment of the said plates in a rocking
bath lined on the inside with carbon plates or aluminium sheeting and containing
an electrolytic solution, the said lining and the plate to be treated forming
part of an electric circuit and being so arranged that the said plate shall be
connected to the negative pole of the battery, the said bath being kept moving
during the electrolytic action and the plate sponged from time to time and subse
quently treated with carbonate of magnesia, water and methylated spirit, as herein-
before described.
Dated this 19th Thy of Mano 1000
G. F. REDFERN & Co..
4, South Street, Finsbury, London,
Agents for the Applicant.