IMPROVEMENTS IN NICKEL-PLATING AND IN APPARATUS FOR ELECTRO-PLATING WITH NICKEL OR OTHER METAL
Year: 1882

page_text: LETTERS PATENT to John Edlington Chaster, of Manchester, in the County of
Lancaster, for an Invention of "IMPROVEMENTS IN NICKEL-PLATING AND
IN APPARATUS FOR ELECTRO-PLATING WITH NICKEL OR OTHER METAL."
PROVISIONAL SPECIFICATION left by the said John Edlington Chaster at
the Office of the Commissioners of Patents on the 2nd January 1882.
JOHN EDLINGTON CHASTER of Manchester in the County of Lancaster
"IMPROVEMENTS IN NICKEL PLATING AND IN APPARATUS FOR ELECTRO
PLATING WITH NICKEL OR OTHER METAL"
•
This Invention consists in an improved system of electro plating and in convenient
apparatus therefore by which means much less electro motive force can be used and
great economy secured.
The Invention consists—
1st In using the double citrate of nickel and ammonia instead of the double
sulphate.
2d In new arrangement and construction of battery for electro-plating with
nickel. The cells of this battery, three in number are a modification of Daniel's in
which the zinc is placed in an inner porous cell in a half saturated solution of zinc
sulphate. This cell is placed in a copper or lead cell containing saturated copper
sulphate solution. This solution is kept saturated by means of addition of crystals
of copper sulphate added from time to time. By theso means the current froin the
battery is constant different from all other batteries used for nickel plating and
further the electro-motive force of the battery is such that the solution is not
decomposed and is merely suflicient to carry over the metal from the anode to the
article to be plated and does so with the smallest amount of gas given off on the
article being plated.
This nickel is deposited on iron articles direct without being previously plated
with copper as it adheres firmly to the iron owing to the small amount of gas being
given off whilst plating.
3 A simple arrangement of portable apparatus for nickel plating. It consists
in a box divided in two by a partition; on one side are three cells in series on the
other a tank lined with lead or simply of wood well covered with paraffin wax, in
which the two anodes of nickel are suspended at each end and the cathode a
simple bar across the tank, upon which the articles to be electroplated arc
suspended by wires.
Connection with the battery is made in the usual manner.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Edlington Chaster in the Great Seal Patent Office on the
1st July 1882.
JOHN EDLINGTON CHASTER of Manchester in the County of Lancaster
"IMPROVEMENTS IN NICKEL-PLATING AND IN APPARATUS FOR ELECTRO-PLATING
WITH NICKEL OR OTHER METAL."
The state of the art of nickel plating at the present time is as follows:-
A strong solution of the double sulphate of nickel and ammonia is used as the
electro depositing solution. This salt requires a high electromotive force for its
decomposition and this force while decomposing the nickel salt also largely decomposes
the water covering with gas any iron article to be plated. The gas prevents the
nickel from uniformly covering the iron. To obviate this the iron article is first
electro-plated with copper and then the copper surface is plated with nickel.
Owing to the high electromotive force required under the present process it
is impracticable to use a constant battery of low force but Bunsen and other
cells of higher power have to be used, necessitating considerable attention and
frequent manipulation while the variation of the current requires frequent
examination of the articles as it is impracticable to guage the thickness of the
coating by the time.
Now I have found that by using the double citrate of nickel and ammonia a
much lower electro-motive force is sufficient and by a modification of the Daniel
cell I can obtain a constant current with three cells with quite sufficient electro-
motive force to decompose the double citrate aforesaid. I can thus construct a
small compact portable apparatus sufficient for electroplating small articles in place
of the heavy cumbrous plans hitherto used.
My Invention is best explained by describing the simplest form of my apparatus,
but I do not confine myself to these exact details.
Fig 1 is a plan of apparatus arranged in a box with lid capable of locking up
with everything in order for work.
Fig 2 section on line x. x. Fig 1. Fig 3 section on line y. y. Fig 2.
In these A A A are three wooden cells made watertight by a coating of parallin
or lined with lead or containing earthenware cells to hold the liquids. B wooden
electroplating tank, made tight in a similar manner. C. C. C. are three copper
plates with cage C to contain crystals of copper sulphate, D. D. D. porous cells
E zinc plates.
The outer cells A contain a solution of copper sulphate kept saturated by crystals
of the salt placed in C". In cells D D is a semi-saturated solution of sulphate of
zinc. The three cells are arranged in a single series as shown.
FF are anodes consisting of nickel plates, G metallic bar or cathode from which
the article to be electro-plated is suspended by a conducting wire.
The tank B is filled nearly to the top of the nickel plates with a strong-say ³/
saturated solution of double citrate of nickel and ammonium.
The mode of operating is as follows. The apparatus being coupled up as shown
in the Drawings. The liquids are poured into their respective cells and tank and
one or more articles to be plated are separately suspended from the cathode bar G.
The sulphate of copper is gradually decomposed in the battery forming metallic
copper on the copper plates and sulphate of zinc (at the expense of the zinc plates)
in the porous cells.
The electromotive force thus generated decomposes the citrate of nickel and
ammonium in the tank. The nickel passing to the object to be electroplated and

page_text: the free citric acid and citrate of ammonium combining with the nickel of the
anode to form a fresh quantity of citrate of nickel and ammonium. All that is
required to keep the apparatus in constant operation till the plates are eaten away
is to keep the supply of copper sulphate and to, say once a day, draw out a few
spoonfuls of the sulphate of zinc solution substituting water therefor, the quantity
so withdrawn depending upon the state of saturation and varying with the work
performed.
Having now described my Invention and the best mode known to me of carrying
the same into effect I wish it to be understood that what I believe to be new and
desire the hereinbefore in part recited Letters Patent is-
1. The application of the double citrate of ammonium and nickel as an electro-
plating solution.
2. Depositing nickel from a solution of a nickel salt (double citrate of nickel and
ammonium) capable of being decomposed with a very small amount of electro-
motive force and thus avoiding the liberation of gas upon the object to be plated.
3. The constant galvanic battery for electroplating consisting of cells containing
no free acid but a constantly saturated solution of sulphate of copper in the outer
cell and a dilute solution of the conducting salt sulphate of soda in the porous
cell.
4. The portable apparatus for nickel plating consisting in a divided box formed
of wood made impervious to acids by means of paraffin or a lead lining, in which
the battery and the tank are placed side by side each cell of the battery and the
tank forming a separate division of the box substantially as shown and described.
In witness whereof I the said John Edlington Chaster have hereunto set
my hand and seal this Thirtieth day of June in the year of our Lord
One thousand eight hundred and eighty two.
JOHN EDLINGTON CHASTER.
(L.S.)