An Improved Process for Preparing a Metallic Covering for Giving a Non-oxydising or only Slightly Oxydising Coating to Wood and other Materials or Objects.
Year: 1886

page_text: Date of Application, 7th Aug., 1886.
Complete Left, 2nd Feb., 1887.
Complete Accepted, 10th May, 1887.
An Improved Process for Preparing a Metallic Covering for Giving
a Non-oxydising or only Slightly Oxydising Coating to Wood
and other Materials or Objects.
We EHREGOTT SCHRÖDER and HUGO PERNER both of No. 6 Brandenburgstrasse
Berlin in the German Empire, Engineers, do hereby declare the nature of said
invention for "AN IMPROVED PROCESS FOR PREPARING A METALLIC COVERING FOR
GIVING A NON-OXYDISING OR ONLY SLIGHTLY OXYDISING COATING TO WOOD AND
OTHER MATERIALS OR OBJECTS," to be as follows:―
The object of this invention is the production of a metal-foil like stuff of any desired
superficial area and of great firmness and elasticity which by means of glue or other
known fixing substance may be fixed on wood and other materials or objects with a
view to preservation or adornment.
For this purpose metals such as gold, silver, nickel, copper, lead, tin, iron, etcetera
are precipitated by electrolysis or galvanic process in the form of a thin layer or foil
on to thin paper, fine woven fabric or other readily pliable substance, which has been
previously impregnated with a metallic solution and then satinised. The coating thus
prepared is then ready for fixing to the material or object it is intended to preserve or
adorn.
In cases where it is subjected to a high temperature the fabric or lining underneath
will in part carbonise and form a layer capable of withstanding very high
temperatures.
CAPITAINE & VON
HERTLING,
89, Chancery Lane, London, W.C.,
Agents for the Applicants.

page_text: An Improved Process for Preparing a Metallic Covering for Giving
a Non-oxydising or only Slightly Oxydising Coating to Wood
and other Materials or Objects.
We, EHREGOTT SCHRÖDER and HUGO PERNER both of Berlin in the German
Empire, Engineers, do hereby declare the nature of said invention for "AN IMPROVED
OR
PROCESS FOR PREPARING A METALLIC COVERING FOR GIVING A NON-OXYDISING
ONLY SLIGHTLY OXYDISING COATING TO WOOD AND OTHER MATERIALS OR OBJECTS ""
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The object of this invention is the production by electrolysis of metal foil or metal
foil-like stuff of any desired superficial area and of great firmness and elasticity which
by means of varnish, glue or other known fixing substance may be fixed on wood
and other materials or objects with a view to preservation or adornment.
Metal foil has hitherto been produced by rolling or hanımering the metal until it
attains the customary degree of thinness, which by such a purely mechanical treat-
ment is limited as in the rolling operation when the metal has reached a certain
degree of thinness, this cannot be exceeded without tearing or opening, similarly the
length and width of the foil so obtained is limited, the same obtains, though it may
be to a lesser extent, in the hammering operation.
According to this invention, flat, cylindrical or other bodies are provided sufficiently
strong to withstand shocks or blows due to accidents which may happen in the course
of the process, and of a material such as metal which is a good conductor of electricity.
These bodies serve the purpose of taking up the precipitate of the metal from which
the foil is to be obtained and are placed in metallic solutions and subjected to the
action of electric currents. After the surfaces of the bodies have become evenly
coated over with the precipitates hereby formed, such extremely thin coating is drawn
off, which may without difficulty be done if the bodies previous to placing them in the
metallic solution are covered over with a very thin coating of varnish such as is used
for gilding, or spirit varnish (spiritus-firniss) such that the action of the electric
currents shall not be obstructed or only very slightly so. In the case of precious
metals where it may be required to form as thin a foil as is possible without tearing
when drawn from the body on to which it has been precipitated, this latter with the
metallic precipitate thereon is placed in a bath of a copper solution and the thin
coating of precious metal is so long coated over by electrolysis with a copper precipi-
tate, until the two collective coatings attain a thickness sufficient to allow of the foil
so formed to be drawn off the body.
Another method of strengthening foil of precious metal that has been precipitated
on a body in the way described, consists in glueing or otherwise fixing thin paper over
the precipitate coated body, and drawing off the paper and thin foil formed of the
precipitate both together. Woven fabrics may be used instead of paper.

page_text: Finally, paper itself may be employed as the body on which to precipitate the
metal, by preparing the pulp or the ready made paper so as to render it suitable for
receiving metallic precipitates. The preparation of the paper pulp for this purpose
may be effected by adding thereto finely pulverised metals or metallic salts.
Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed, we declare that what we claim is :
1. The process of producing gold, silver, nickel, copper and other metal foil of any
desired superficial area and of great thinness, in coating-by means of electrolysis--
bodies with the desired metal and then drawing off the precipitated foil, substantially
as described.
2. In order in the case of precious metals-to strengthen the precipitate or layer
thereof produced by the process referred to, for the purpose of insuring a safe with-
drawal thereof the introduction of the coated body into a bath of copper or other
metallic solution, in which bath a coating of the metal of the solution is precipitated-
by means of electrolysis-on to the coating of precious metal and the double coating
drawn from the body together, substantially as described.
3. In order to strengthen the precipitate or layer of metal, produced by the process
referred to, for the purpose of insuring a safe withdrawal thereof-the affixing of
paper or woven fabric to the coated body and the withdrawal of the paper or fabric
together with the precipitated metal from the body substantially as described.
4. The production of foil in the manner that a readily pliable material such as paper,
woven fabric or the raw material serving for their manufacture, as paper pulp for
instance is, made suitable for galvanic precipitation thereon, and then coated over with
a thin layer of metal substantially as described.
Dated this 1st day of February 1887.
CAPITAINE & VON HERTLING,
89, Chancery Lane, London, W.C.,'
Agents for the Inventors.
CAPITAINE & VON HERTLING,
89, Chancery Lane, London, W.C.,
Agents for the Inventors.