AN IMPROVEMENT IN THE MANUFACTURE OF ANTI-FOULING PAINTS OR COM- POSITIONS
Year: 1883

page_text: LETTERS PATENT to Alexander Melville Clark of the. firm of A. M and
W. Clark of 53 Chancery Lane in the County of Middlesex, Fellow of the
Institute of Patent Agents for an Invention of AN IMPROVEMENT IN THE
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 4th July 1883.
ALEXANDER MELVILLE CLARK of the firm of A. M. and W. Clark of 53 Chancery
Lane in the County of Middlesex Fellow of the Institute of Patent Agents,.
"AN IMPROVEMENT IN THE MANUFACTURE OF ANTI-FOULING PAINTS OR COM-
POSITIONS." [communicated to him from abroad by Charles Dubois, of Marseilles,
France]
This Invention relates to a new combination of ingredients to be mixed with
any paint or other vehicle for coating ships bottoms whereby the said paint is
endowed with antifouling properties in the highest degree and the surface to
which the same is applied is most effectually preserved.
The Invention consists in the combined employment of the sulpho-cyanides of
copper and the arseniates of mercury in any kind of paint or composition for
marine purposes. It is unnecessary to here define the nature of the chemical
reactions which occur between the sea water and these two ingredients when used
together and mixed with paint or other vehicle, it being sufficient to say that
mixtures of sulpho-cyanide of copper and arseniate of mercury. incorporated with
paint or other vehicle impart poisonous and preservative qualities to the latter in
a very much higher degree than if the one or other ingredient were used alone.
The proportions of sulpho-cyanide and arseniate relatively to one another, or of
the compound of the two relatively to the amount of paint or other vehicle may
vary as the combined use of the said ingredients in any proportions, will always
have the effect of producing corrosive and poisonous qualities of a much more
powerful character than would result from the use of an equivalent weight of
either ingredient without the other.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Patent Office on the 4th January
1884.
ALEXANDER MELVILLE CLARK of the firm of A. M. and W. Clark of 53 Chancery
Lane, in the County of Middlesex, Fellow of the Institute of Patent Agents.
"AN IMPROVEMENT IN THE MANUFACTURE OF ANTIFOULING PAINTS OR COM-
POSITIONS A communication to me from abroad by Charles Dubois of Marseilles,
France,
"
This Invention relates to a new combination of ingredients to be mixed with
any paint or other vehicle for coating ships' bottoms. whereby the said paint or
vehicle is endowed with anti-fouling properties in the highest degree and the
surface to which the same is applied is most effectually preserved.
The Invention consists in the combined employment of the sulpho-cyanide of
copper and the arseniate of mercury in any kind of paint or composition for
marine purposes. It is unnecessary to here define the nature of the chemical
reactions which occur between the sea water and these two ingredients when used
together and mixed with paint or other vehicle, it being sufficient to say that
mixtures of sulpho-cyanide of copper and arseniate of mercury incorporated with
paint or other vehicle impart poisonous. and preservative qualities to the latter
in a very much higher degree than if the one or other ingredient were, used
alone.
The proportions of sulpho-cyanide and arseniate relatively to one another, or of
the compound of the two relatively to the amount of paint or other vehicle may
vary, as the combined use of the said ingredients in any proportions will always
have the effect of producing corrosive and poisonous qualities of a much more
powerful character than would result from the use of an equivalent weight of
either ingredient without the other.
The proportions at present preferred are:-
Sulphio-cyanide of copper
Arseniate of mercury
Ships' paint (or other vehicle such as mineral, animal or
vegetable oils, fats, spirits, varnishes, blacks, tars &
colored or not suitable for coating and preserving
ships' bottoms) sufficiently fluid to incorporate the
powdered ingredients above named
20 per cent
15 per cent
65 per cent
Having described the nature of the said Invention and the manner of performing
the same I would observe that the use of the cyanides and sulphocyanides of
copper alone has been secured by previous patents and the use of arseniate of
mercury alone is not new and I do not therefore claim the use of either ingredient
separately but what I claim as the Invention to be protected by the hereinbefore
in part recited Letters Patent is:
The combined employment of sulpho-cyanide of copper and arseniate of mercury
in any kind of paint or composition for coating ships' bottoms, whatever may be
the proportions of these ingredients relatively to one another or of their combination
relatively to the weight of the paint or other vehicle with which they are mixed.
In witness whereof I the said Alexander Melville Clark, have hereunto set my
hand and seal this fourth day of January A.D. 1884.