Process of and Materials for Coating Metallic Surfaces for the Prevention of Fouling and Corrosion and Reducing Surface Friction.
Year: 1891

page_text: Date of Application, 4th Dec., 1891
Complete Specification Left, 5th Sept., 1892-Accepted, 15th Oct., 1392
PROVISIONAL SPECIFICATION.
A Process of and Materials for Coating Metallic Surfaces for the
Prevention of Fouling and Corrosion and Reducing Surface
Friction.
I JOSEPH CRAWHALL CHAPMAN, Chartered Patent Agent, of 70 Chancery
Lane in the County of London do hereby declare the nature of this invention
which has been communicated to me from abroad by John Mathews James of
Shinagawa, Tokyo, Japan, Retired Naval Officer, to be as follows:-
This invention has for its object to coat and prepare metallic surfaces such as
propellers of steamships, turbines and such like devices of all kinds in such
manner that they shall be effectually preserved from fouling and corrosion
and also that by reducing surface friction their speed and efficiency shall be
increased.
The invention consists in the employment and application to the metalli
surfaces of the substance known as "Japanese lacquer" (being the produce of the
Urushi-no-ki) in such proportions and commixtures as will produce such a coating
and surface upon the article treated as to effect my objects. The surface before
treatment is thoroughly cleansed of all greasy and other foreign matters and
rubbed as bright as practicable; then first a tenacious cement composed of a
mixture of crude lacquer and finely-ground calcined clay or equivalent is applied
to fill up inequalities and to ensure an even surface; this is thoroughly dried and
hardened by any suitable means, and then rubbed smooth with a specially prepared
charcoal in order to remove gloss and dull the surface.
A second composition is next applied to the above consisting of crude and
middling-refined lacquer which is dried hardened and, dulled as above, the
operations being repeated until the required condition of surface is obtained. To
this next a mixture of best-refined and middling-refined lacquer is applied and the
process of drying hardening and dulling are repeated as before.
Next in the same manner is applied to the partly finished surface a coat of
best-refined lacquer alone which after being sufficiently dried and hardened is
reduced to an even surface by the attrition of another special kind of charcoal.
After this the whole surface is rubbed over with middling-refined lacquer applied
with any suitable soft material, and when dried is or may be completed by rubbing
smooth with a fine powder (for example of deer's horn or the like). This last
mentioned process may be repeated as often as necessary to produce a surface
which will be perfectly smooth and of great lustre.
When using the best refined lacquer above mentioned a small proportion of
oxide of iron and plum juice or other suitable substances may be added to assist in
colouring and toning the lacquer.
Duted this 4th day of December 1891
J. C. CHAPMAN,
Agent.
COMPLETE SPECIFICATION.
A Process of and Materials for Coating Metallic Surfaces for the
Prevention of Fouling and Corrosion and Reducing Surface
Friction.
I, JOSEPH CRAWHall Chapman, Chartered Patent Agent, of 70, Chancery
Lane, in the County of London, do hereby declare the nature of this invention,
which has been communicated to me from abroad by John Mathews James, of
Di Q77

page_text: Shinagawa, Tokyo, Japan, Retired Naval Officer, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention has for its object to coat and prepare metallic surfaces, such as
the hulls of vessels, the propellers of steamships, turbines, and such like devices of
all kinds in such manner that they shall be effectually preserved from fouling and
corrosion and also that by reducing surface friction, their speed and efficiency when
submerged shall be increased.
The invention consists in the employment and application to the metallic surfaces
of the substance known as "Japanese lacquer (being the produce of the
Urushi-no-ki), or it may be a lacquer of equivalent nature and properties, in such
proportions and commixtures as will produce such a coating and surface upon the
article treated as to effect my objects. The surface before treatment is thoroughly
cleansed of all greasy and other foreign matters and rubbed as bright as practicable.
Then first a tenacious cement composed of a mixture of crude lacquer and finely
ground calcined clay or equivalent is applied to fill up inequalities and to ensure
an even surface. This is thoroughly dried and hardened by any suitable means,
which under favourable conditions of temperature may take from 1 to 2 days.
The new surface is then rubbed smooth with suitably comminuted charcoal in order
to remove gloss and dull the surface uniformly and efficiently for receiving the
second coating. A second composition is next applied to the surface acquired as
above, consisting of crude and middling-refined lacquer in equal or approximately
equal quantities, which is then dried and hardened in the same manner as the above
first coating, the process taking from 2 to 3 days. It is then dulled as above set
forth, to adapt it to receive the next coating. The same or similar operations are
repeated for the 3rd and 4th and successive coatings until the required condition
of surface is obtained. Then next a further (or say 5th) coat is applied composed
of a mixture of about parts of best-refined and parts of middling-refined
lacquer, and the processes of drying, hardening and dulling are repeated as before,
requiring from about 1 to 2 days.
Next in the same manner is applied to the partly finished surface a supplemental
(or say 6th) coat of best refined lacquer alone, which, after being sufficiently dried
and hardened, as above, is reduced to an even surface by the attrition of another
suitably comminuted charcoal.
After this the whole surface is finally rubbed over with middling-refined lacquer
applied with any suitable soft material, and when dried is or may be completed by
rubbing smooth with a fine powder (for example, of deer's horn or the like).
This last mentioned process may be repeated as often as necessary to produce
surface which will be perfectly smooth and of great lustre.
al
When using the best-refined lacquer above mentioned, a small proportion of
oxide of iron and plum juice or other suitable substances may be added to assist in
colouring and toning the lacquer as required.
I would have it understood that I do not limit my invention to the exact pro-
portions, number of coatings, or periods of time. specified above, as they may be
varied without departing from the nature of my invention, but I have found such
directions as above given to give good results in practice; also since filing my
Provisional Specification, I have found that other lacquers exist which are as well
adapted and applicable to my purpose as the particular Japanese lacquer I therein
mentioned, and therefore I do not wish to confine myself particularly to Japanese
lacquer, but to include also its equivalent.
Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The herein before described process for coating metallic surfaces, consisting in
first coating the previously cleansed surface with a tenacious cement composed of

page_text: crude lacquer of suitable kind and finely-ground calcined clay, then thoroughly
drying and hardening, and then dulling the resulting surface with charcoal as
described; afterwards applying separately thereto a series of coatings of varying
grades of lacquer, substantially in the proportions specified and treating same in
the manner set forth until the required surface is obtained, then finishing the finally
acquired surface by rubbing same until smooth and lustrous, substantially as and
for the purposes set forth.
Dated this 5th day of September 1892.
J. C. CHAPMAN, C.P.A.,
70, Chancery Lane, London, W.C.