Improvements in the Production of Easily Separable Metallic Deposits.
Year: 1892

page_text: Date of Application, 7th Oct., 1892
Complete Specification Left, 5th June, 1893-Accepted, 8th July, 1893
PROVISIONAL SPECIFICATION.
Improvements in the Production of Easily Separable Metallic
Deposits.
We, CURT ADOLF NETTO of 14 Eschenheimer Landstrasse, Engineer, JOHANN
PFLEGER, of 9 Blücherplatz, Electro-chemist, and LINCOLN HAUSMANN, of
21 Kochstrasse Merchant, all of Frankfort on the Main, in the Empire of
Germany, do hereby declare the nature of this invention to be as follows:-
Our invention relates to the production of easily separable metallic deposits by
the galvano-plastic method by means of plates or moulds, coated with nickel or
made of alloys of nickel constituting cathodes upon which the deposit is produced,
the object being to render the surfaces of such plates or moulds perfectly smooth
and thus avoid the necessity for subsequently polishing them.
For this purpose we treat the said plates or moulds with chromic salts or salts of
manganese. The only objection to the use of pure nickel has been the fact that
its surface has always hitherto been porous and we are therefore by our method of
treatment euabled to substitute plates or moulds made of pure nickel for those
coated with nickel or made of alloys of nickel.
Continued practical experiments with our method of treatment have proved that
other metals may be employed as cathodes or bases for separable metallic deposits
provided only that they are capable of taking a smooth surface, that is to say,
provided that they can be manufactured with a smooth surface, and are unaffected
by the electrolyte. To this class, which are suitable for substitutes for nickel, or
for alleys of nickel, in the process described, the following were found to belong,
viz. cobalt, iron or steel, copper, lead (hard or soft) cadmium, antimony, aluminium,
tin, alloys of these metals (as also compounds or alloys of the above capable of
resisting the action of the electrolyte, such as ferro-silicon, ferro-chromium, ferro-
manganese, ferro-titanium) platinum, gold and silver.
Such metals, especially if they are very costly, may be employed in the form of
thin sheets or as coatings on the bases or cathodes. In the same way plates of
glass or porcelain may be used as bases or cathodes if they be first coated with the
metals above mentioned of which in this case the precious metals, viz. gold, silver
and platinum, are especially suitable, though others, such as nickel may also be
employed.
As already stated, the upper surface of the nickel may be treated with oxidizing
agents, such as salts of chromium and manganese, for the purpose of rendering the
metallic deposit more easily separable. By this means all the pores of the surface
are got rid of, and easily separable deposits of from 001 to 002 of a millimetre in
thickness may be produced. These oxidizing agents may, in accordance with the
present invention, be likewise employed for other bases or moulds, for the above
named metals or their alloys in particular, furthermore, other oxidizing agents
than those above described for nickel or alloys of nickel, such, especially, as
peroxide of hydrogen or oxygenated water, ferricyanide of potassium, chloride of
calcium, the oxygen of the air at a high temperature, and oxygen produced
electrolytically may be employed for any metals or alloys. A layer of oxide
may also be produced upon the surface of the metal by precipitation of oxides.
upon the latter.
In the practical experiments already referred to it was furthermore found that
the layer which renders the metallic deposit more easily separable need not consist
of a metallic oxide, but may consist of other compounds of metals with metalloids,
or with cyanogen, if only the compound be insoluble in the electrolyte, and
conductor of electricity

page_text: Thus copper plates may be coated with cuprous chloride and silver plates with
cyanide of silver. It is not always essential to the production of this protective
layer from the combination of metal with metalloid that the metal of the
combination should be contained in the surface of the printing plate or mould;
thus a copper plate may be coated with a thin layer of silver and the latter
converted into a combination of the silver with a metalloid.
Such layers possess the advantage that their production does not alter the
form of the printing plate or mould, nor attack it, and may always be easily
repeated.
Dated the 7th day of October 1892.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in the Production of Easily Separable Metallic
Deposits.
We, CURT ADOLF NETTO, of 14, Eschenheimer Landstrasse, Engineer, JOHANN
PFLEGER, of 9, Blucherplatz, Electro-chemist, and LINCOLN HAUSMANN, of
21, Kochstrasse, Merchant, all of Frankfort-on-the-Main, in the Empire of
Germany, 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 :-
Our invention relates to the production of easily separable metallic deposits in
the form of metal sheets, plates or the like by the galvano-plastic method by
means of plates or moulds, coated with nickel or made of alloys of nickel, con-
stituting cathodes upon which the deposit is produced, the object being to render
the surfaces of such plates or moulds free from pores and perfectly smooth and
thus avoid the necessity for subsequently polishing them.
For this purpose we treat the said plates or moulds with chromic salts or salts
of manganese. The only objection to the use of pure nickel has been the fact
that its surface has always hitherto been porous and we are therefore by our
method of treatment enabled to substitute plates or moulds made of pure nickel for
those coated with nickel or made of alloys of nickel.
Continued practical experiments with our method of treatment have proved that
other metals may be employed as cathodes or bases for separable metallic deposits
provided only that they are capable of taking a smooth surface, that is to say,
provided that they can be manufactured with a smooth surface, and are unaffected
by the electrolyte. To this class, which are suitable for substitutes for nickel, or
for alloys of nickel, in the process described, the following were found to belong,
viz. cobalt, iron or steel, copper, lead (hard or soft) cadmium, antimony,
aluminium, tin, alloys of these metals (as also compounds or alloys of the above
capable of resisting the action of the electrolyte, such as ferro-silicon, ferro-
chromium, ferro-manganese, ferro-titanium) platinum, gold and silver.
Such metals, especially if they are very costly, may be employed in the form of
thin sheets or as coatings on the bases or cathodes. In the same way plates of
glass or porcelain may be used as bases or cathodes if they be first coated with
the metals above mentioned of which in this case the precious metals, viz., gold,
silver and platinum are especially suitable, though others, such as nickel may also
be employed.
As already stated, the upper surface of the nickel may be treated with oxidizing
agents, such as salts of chromium and manganese, for the purpose of rendering
the metallic deposit more easily separable. By this means all the pores of the
surface are got rid of, and easily separable deposits of from 001 to 002 of a
millimetre in thickness may be produced. These oxidizing agents may, in accordance
with the present invention, be likewise employed for other bases or moulds, for

page_text: the above named metals or their alloys in particular, furthermore other oxidizing
agents than those above described for nickel or alloys of nickel, such, especially,
as peroxide of hydrogen or oxygenated water, ferricyanide of potassium, chloride
of calcium, the oxygen of the air at a high temperature, and oxygen produced
electrolytically may be employed for any metals or alloys. A layer of oxide
may also be produced upon the surface of the metal by precipitation of oxides
upon the latter.
In the practical experiments already referred to it was furthermore found that.
the layer which renders the metallic deposit more easily separable need not consist
of a metallic oxide, but may consist of other compounds of metals with metalloids,
or with cyanogen, it only the compound be insoluble in the electrolyte, and a
conductor of electricity.
Thus copper plates may be coated with cupreous chloride and silver plates with
cyanide of silver. It is not always essential to the production of this protective
layer from the combination of metal with metalloid that the metal of the com-
bination should be contained in the surface of the printing plate or mould; thus a
copper plate may be coated with a thin layer of silver and the latter converted
into a combination of the silver with a metalloid.
Such layers possess the advantage that their production does not alter the form
of the printing plate or mould, nor attack it, and may always be easily repeated.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The production of easily separable metallic deposits by means of plates or
moulds (constituting cathodes upon which the deposit is produced) made of pure
nickel, or coated with or made from other metals easily prepared with a smooth
surface, such as cobalt, iron or steel, copper, lead, silver, gold, platinum, cadmium,
antimony, aluminium, tin, and also their alloys, as well as ferro-chromium, ferro-
silicon, ferro-manganese, ferro-titanium, substantially as herein before described.
2. The treatment of plates or moulds having their upper surfaces coated with
nickel, or plates or moulds made of alloys of nickel or of other metals or alloys
or compounds of metals such as those referred to in Claim 1, with salts of chromium
or manganese, for the purpose of producing easily separable metallic deposits,
substantially as hereinbefore described.
3. The treatment of plates or moulds having surfaces coated with nickel or
plates or moulds made of nickel alloys or of other metals or alloys, or compounds
of metals such as those referred to in Claim 1 with oxidizing agents, such as
peroxide of hydrogen, ferricyanide of potassium, oxygen of the air, and electro-
lytically generated oxygen, or by precipitating upon the surfaces of the printing
plates or moulds, a layer of oxide or of compounds of metals with metalloids or
with cyanogen, which compounds are insoluble in the electrolyte and electrically
conductive, the metal of the compound being contained or not in the surface of the
printing plate or mould which is to be protected and which serves as a base for
the deposited metal, substantially as hereinbefore described.
4. Metal sheets, plates, or the like produced by depositing metal by the galvano-
plastic method upon plates or moulds made substantially as hereinbetore described.
Dated the 5th day of June 1893.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.