IMPROVEMENTS IN PROTECTING METALLIC AND OTHER SURFACES FROM CORROSION AND DECAY
Year: 1855

page_text: AND DECAY." A communication.
PROVISIONAL SPECIFICATION left by the said Benjamin Rosenberg at
the Office of the Commissioners of Patents, with his Petition, on the
28th November 1855.
I, BENJAMIN ROSENDERO, of New Charles Street, City Road, in the County of
Middlesex, Merchant, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN PROTECTING METALLIC AND OTHER SURFACES FROM CORROSION
AND DECAY," a communication to me from abroad, to be as follows:-
}
The surfaces of the objects which are to be protected according to my-
improved process must be first thoroughly freed from grease and other impu-
rities, not by means of acids, but, by preference, by the application of a strong>
heat. Any specks of grease, &c. remaining after this process are to bo rubbed
off with glass, emery paper, or similar means, and by the same means the
surfaces smoothed. This being done, the surfaces are covered with a paint.
or lackering, composed in about the following proportions:-One hundred
pounds of triturated white lead, two gallons and a quarter of copal varnish,
one gallon and an eighth of spirits of turpentine, one gallon and an eighth

page_text: of linseed oil, and, for the purpose of imparting a color to the paint, a small
quantity of minium or red lead. Great care should be taken to spread the
said paint or lackering as thinly and evenly as possible over the surface. It
is of course obvious that the proportions and the coloring matters may, to
some extent, be varied.
The objects painted or coated in this manner are then placed in a closed
stove, heated from the outside, and free from dust, where they must be dried
or baked for six hours, subject to a heat of at least 250 degrees Fahrenheit.
When removed from the stove, the objects are placed in another room having
a temperature of 70 to 80 degrees Fahrenheit, and in this room they are left
for three days; after this, the process of painting and dryins is repeated, as
described, only the second coat of paint should be laid on a little more thickly
than the first; generally two coats of paint will be found sufficient. But in
order to insure still greater safety, the surfaces, after being painted and
thoroughly dried twice, may be coated with copal varnish, and then left to dry
in a room having the common temperature, or in the open air.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Benjamin Rosenberg in the Great Seal Patent Office on
the 28th May 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BENJAMIN
ROSENBERG, of New Charles Street, City Road, in the County of Middlesex,
Merchant, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of November, in the year of our
Lord One thousand eight hundred and fifty-five, in the nineteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Benjamin Rosenberg, Her special licence that I, the said Benjamin
Rosenberg, my executors, administrators, and assigns, or such others as I, the
said Benjamin Rosenberg, my executors, administrators, and assigns, should at
any time agree with, and no others, froni tinie to time and at all times
thereafter during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain and,
Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE-:
MENTS IN PROTECTING METALLIC AND OTHER SURFACES FROM CORROSION, AND DECAY,"
upon the condition (amongst others) that I, the said Benjamin Rosenberg,
my executors or administrators, by an instrument in writing under my, or.

page_text: their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same was
to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of
5 the said Letters Patent.
NOW KNOW YE, that I, the said Benjamin Rosenberg, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
) My said Invention relates to the protection from corrosion and decay of the
surfaces of various metallic substances, particularly of sheet iron, and especially
of such vessels of sheet iron as are used in curing and refining sugar, and are
called sugar moulds or sugar pots. And my said Invention is carried out in
the following manner:-
Those surfaces of the vessels aforesaid, which are to be protected from corro-
sion, according to my improved process, must be first thoroughly cleaned and
freed from grease and other impurities, not by means of diluted acids, as is
commonly done in such cases, but, by preference, by the application of a
strong heat, for which purpose they may be exposed to the action of a fire
emitting a bright flame. Any specks of grease or other impurities remaining
after this process are to be carefully rubbed off with glass, sand, or emery
paper, or other substances acting in a similar way, and by the same means the
surfaces are made smooth.
I now prepare a paint or lackering, which I compose of the following ingre-
dients, in about the following proportions, viz:-To one hundred pounds
avoirdupois of triturated white lead, I add two gallons and a quarter of copal
varnish (consisting of gum copal dissolved in spirits of turpentine), one gallon
and an eighth of spirits of turpentine, and one gallon and an eighth of linseed
oil. For the purpose of giving a colour to the paint, a small quantity of red
lead or minium is added. It is obvious of course that the proportions of the
ingredients and of the colouring matters of the paint may be varied to some
extent. The paint should be well ground and incorporated, so as to be quite
homogenous, and if it should be found not to work freely enough with a brush,
it is to be diluted with a little more linseed oil. The surfaces to be protected
from corrosion are now to be covered or coated with the paint or lackering by
means of a brush, and the greatest care should be taken to spread the said
paint as thinly and evenly as possible over the surfaces.
The vessels operated upon are next removed to the interior of a close stove
or drying chamber, and are dried or baked there for about six hours, subject to

page_text: an uniform temperature of at least two hundred and fifty degrees Fahrenheit.
As it is required that the interior of the stove or drying chamber should be free
from dust, the heat must be applied to its bottom, or bottom and sides from
the outside, and the drying chamber may be constructed of bricks, or iron, or
both materials combined, according to convenience.
When the vessels have been baked for the time specified at the said tem-
perature, the surfaces covered with the paint will present an appearance
as if they had been glazed or enamelled, and this is a sign that the baking bas
been carried on sufficiently. The vessels are then removed from the drying
chamber and put in another room having a temperature of seventy to
eighty degrees Fahrenheit, and in this room they are left for three days.
After this, the process of painting and drying, as described, is repeated, only
the second coat of paint should be laid on a little more thickly than the first.
Generally two coats of paint will be found sufficient for the purpose intended;
but in order to make the process still more safe and efficient, the surfaces after
being painted and thoroughly dried twice, as described, may be covered with a
thin coat of copal varnish, and then left to dry in a room having the common
temperature, or in the open air. Sometimes I even prefer to apply to the
surfaces three coats of paint, but in this case each coat should be exceedingly
thin.
As the superior protection from corrosion which my process afords to
metallic surfaces is mainly due to the copal varnish being exposed to the
elevated temperature afore-named, I claim as my Invention the fixing the
said paint on metallic surfaces in the manner and by the means herein
described.
In witness whereof, I, the said Benjamin Rosenberg, have hereunto set
my hand and seal, this Thirteenth day of May, in the year of our
Lord One thousand eight hundred and fifty-six.
Witness,
SAUL SOLOMON, Sol',
22, Finsbury Place.
BENJ. ROSENBERG. (L.s.)