IMPROVEMENTS IN NICKEL-PLATING
Year: 1880

page_text: LETTERS PATENT to Jasper Wetter, of the Firm of Herbert and Company,
Solicitors of Patents, of 67, Strand, in the City of Westminster, Civil Engineer,
for an Invention of "IMPROVEMENTS IN NICKEL-PLATING." A communication
from abroad by James Powell, of Cincinnati, State of Ohio, United States of
America.
COMPLETE SPECIFICATION filed by the said Jasper Wetter at the Office
of the Commissioners of Patents on the 18th June 1880.
JASPER WETTER, of the Firm of Herbert and Company, Solicitors of Patents, of
67, Strand, in the City of Westminster, Civil Engineer. "IMPROVEMENTS IN
NICKEL-PLATING." A communication from abroad by James Powell, of Cincinnati,
State of Ohio, United States of America.
The improvements consist in forming nickel-plating solutions, whereby the
difficulty of electrolysing certain acid or neutral nickel salts is entirely overcome.
It is well known to electro-platers and others versed in the art, that the double
salts of nickel as commonly used, such as the double sulphate of nickel and ammonia,
or the double chloride of nickel and ammonia, or the double sellenate of nickel and
ammonia, and other similar double salts, become altered in their proportions and
undergo various changes dependent upon the power of the electric current or the
length of time during which said solutions are subjected to its action. These
changes are particularly liable to occur in such alkaline or neutral solutions as
contain ammonia, from the fact that the ammonia is given off as a gas at the
terminal poles in the solution. On the other.hand the simple acid salts of nickel
have not hitherto been found to answer for the purpose of electro-deposition from
the fact that such solutions refuse to yield a reguline or cobesive deposit of metallic
nickel, but, on the contrary, such nickel solutions as the sulphate, the acetate, the
sellenate, the chloride, the tartrate, the citrate and kindred salts invariably yield
under the influence of the electric current a deposit more or less grey, powdery, or
black and having no adhesiveness or ductility whatever. This seems to be caused
by the evolution of hydrogen and the deposit of a suboxide-or-sub chloride, or other
sub salts along with a certain proportion of metal. The inventor has discovered by
n series of investigations and experiments that the addition of benzoic acid to any
of the salts of nickel (especially when a solution free from alkali is used) corrects
Price Ad

page_text: in a marked degree this tendency to an imperfect deposit, and prevents the evolution
of hydrogen, chlorine, oxygen, nitrogen, and carbon, and consequently the formation
of the sub salts referred to, and that which previously was wholly worthless as a
depositing solution, and yielded a black powdery metal unfit for any practical
purpose, when properly combined with benzoic acid, will then give a tough, cohesive,
and reguline deposit of a beautiful silvery-white metallic-nickel. The inventor has
discovered also, that such a solution becomes more staple in its character, the
solution of the anodes keeping pace with the rapidity of the deposit, thus main-
taining a constant density of the liquid under varied conditions of work. Tho
amount of benzoic acid to be added is not arbitrary but may vary from one eighth
of an ounce to one ounce of acid to each gallon of the solution, according to the
nature of the solution employed; or the benzoic acid may be displaced by the
"benzoates" as, for instance, the benzoate of nickel. The inventor has discovered
also that benzoic acid is equally valuable as an ingredient in the solutions of other
metals, as, for instance, the salts of cobalt, manganese, &c. While I do not confine
myself to any precise formula, so long as benzoic acid or its compounds makes a
constituent of a depositing solution, I prefer, among others, the following:-To one
gallon of pure water, add 4 ounces of sulphate of nickel, 3 ounces of citrate of nickel,
1 ounce of benzoic acid; or the following formula may be used:-To one gallon of
pure water add 2 ounces of chloride of nickel; 2 ounces of citrate of nickel, 2 ounces
of acetate of nickel, 2 ounces of phosphate of nickel, 1 ounce of benzoic acid; or the
following 3 ounces of sulphate of nickel, 3 ounces of citrate of nickel, 1 oz. of
benzoato of nickel, ½ ounce of free benzoic acid; or the following: 3 ounces of
acetate of nickel, 3 ounces of citrato of nickel, 1 ounce of phosphate of nickle,
2 ounces of pyrophosphate of soda, 1 ounce of bisulphite of soda, 5 ounces of aqua
ammonia, 16%. The benzoic acid being sparingly soluble in water it is advisable
to heat the other nickel salts in the proportion of water named, and then, while
boiling hot, add the benzoic acid which will in this state combine with the nickel
salts in a greater degree than with water alone. A great advantage obtained from
the use of the above described solutions arises from the fact that the necessity of
using chemically pure salts or ingredients is dispensed with. In preparing the
sulphate, citrate, acetate, or chloride of nickel, it is preferred to take the common.
commercial acids to dissolve the nickel base because of their cheapness, the other-
wise injurious effects caused by impurities always contained in said commercial
salts or acids being entirely overcome by, the addition of benzoic acid as stated.
The inventor is thus enabled to produce nickel-plating solutions at a much less cost
than has heretofore been attainable. It is obvious that these improved solutions.
are equally applicable to the deposition of nickel in the electrotype process, by
which the metal is caused to deposit over surfaces made conducting by means of a
thin film of plumbago, bronze powder, &c., applied in the usual manner well known
to electrotypers and others skilled in the art, the deposit so made being removable
from the surface, mould, or matrix after the requisito degree of thickness has been
obtained. In such nickel plating solutions as contain ammonia or other alkalino
salts, it is preferred combining with these, as giving the best results, the pyro-
phosphate of soda and the bisulphite of soda, because the inventor has discovered
that the addition of these salts prevent the destructive decomposition to which such
solutions are liable. Finally, salicene or salicylic acid and gallic, or pyrogallic acid
may be added to or substituted in any suitable proportions for tho benzoic acid
herein described.

page_text: 4. The combination of phosphate of nickel with the sulphate or chloride of nickel
in a metallic electro-depositing solution.
5. The combination of citrate with the sulphate or chloride of nickel in a metallic
electro-depositing solution.
6. An electro-depositing solution of the single or double salts of nickel to which
has been added benzoic acid, whether in its free or combined state.
7. The electro-coating of metals with a cohesive and ductile deposit of nickel
from its solution, when said solution is combined with benzoic acid or its
compounds.
8. The electro-deposition of nickel on a non-conducting material prepared in the
manner set forth from its solution to which has been added benzoic acid or its
compounds.
9. An electro-depositing nickel-solution to which has been added pyrophosphate
of soda either with or without the bisulphite of soda.
In witness whereof, I, the said Jasper Wetter, have hereunto set my hand
and seal, this Seventeenth day of June, A.D. 1880.