IMPROVEMENTS IN THE MANUFACTURE OF PAINTS
Year: 1858

page_text: LETTERS PATENT to Patrick Robertson, of the American Commercial
Agency, 1, Sun Street, Cornhill, for the Invention of "IMPROVEMENTS IN
THE MANUFACTURE OF PAINTS."-A communication
Sealed the 9th July 1858, and dated the 20th January 1858.
PROVISIONAL SPECIFICATION left by the said Patrick Robertson at
the Office of the Commissioners of Patents, with his Petition, on the
20th January 1858.
I, PATRICK ROBERTSON, of the American Commercial Agency, 1, Sun
5 Street, Cornhill, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN THE MANUFACTURE OF PAINTS," to be as follows:-
This Invention has for its object improvements in the manufacture of
paints. For these purposes lime is slaked by applying a quantity of water
thereto in a close vessel. To the slaked lime sugar is added and also boiled
Omolasses, the contents of the vessel being well stirred; a quantity of whiting
and dry white lead are then introduced and well mixed therewith, also a
quantity of salt and some refined borax..
The compound is allowed to stand for some hours, it is. then ground in a
mill and ready for use. When colored paints are required the proper coloring
matters are added to the compound above explained. When using the above
paints for the first coats the same are diluted with water, and the last coats
are either coated with a varnish, consisting of linseed oil, turpentine, and
pulverized white resin, or the varnish is mixed with the paints.

page_text: 1
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Patrick Robertson in the Great Seal Patent Office on
the 20th July 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PATRICK
ROBERTSON, of the American Commercial Agency, 1, Sun Street, Cornhill,
send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twentieth day of January, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Patrick Robertson, Her special licence, that I, the said
Patrick Robertson, my executors, administrators, and assigns, or such
others as I, the said Patrick Robertson, my executors, administrators, and
assigns, should at any time agree with, and no others, from time 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 "IMPROVEMENTS IN THE MANUFACTURE OF PAINTS," a communi-
cation, upon the condition (amongst others) that I, the said Patrick
Robertson, my executors or administrators, by an instrument in writing
under my, or 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 immie-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Patrick Robertson, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
; This Invention has for its object improvements in the manufacture of
paints. For these purposes lime is slacked by applying a quantity of water
thereto in a close vessel. To the slaked lime sugar is added and also boiled
molasses, the contents of the vessel being well stirred; a quantity of whiting
and dry white lead are then introduced and well mixed therewith, also a
:
quantity of salt and some refined borax.
The compound is allowed to stand for some hours, it is then ground in a mill
and ready for use. When colored paints are required the proper coloring
matters are added to the compound above explained. When using the above

page_text: paints for the first coats the same are diluted with water, and the last coats
are either coated with a varnish consisting of linseed oil, turpentine, and
pulverized white rosin, or the varnish is mixed with the paints.
And in order that the said Invention may be most fully understood and
readily carried into effect, I will proceed to describe the manner in which it
-is preferred-to conduct the manufacture to produce paints of various different
colors.
To produce a white paint, place in a suitable vessel 10 gallons of water and
add to it.46 lbs. of lime of as pale a color as can be procured; the vessel should
then have a close fitting cover placed on it to protect the lime from the action
of the air. When the lime is slacked, which will be in about two hours and
a half, the, cover should be removed and 7 lbs. of fair, brown, or bleached; or
refined sugar added and well mixed with the lime; then add and mix with
the other materials one quart of molasses; the molasses or syrup should be
boiled for 10 or 15 minutes previously, and added at a boiling heat; next
15 lbs. of whiting and 5 lbs. of dry white lead, both in fine powder, are to be
thrown in, and the composition well stirred. If it is desired to produce a very
rich white, a larger. quantity of white lead may be employed; lastly, 3 quarts
of salt, and 10 ozs. of refined borax are incorporated with the other substances,
and the whole is allowed to stand, and stirred from time to time for about six
hours; at the expiration of this time the paint is run through an ordinary
paint grinding mill; it is then ready for use. To produce cream-colored paint,
12 ozs. of orange chrome is added and incorporated with the white paint com-
position. To produce yellow paint, the proportions of the ingredients are
slightly varied, but the process of manufacture remains unchanged; to 48 lbs.
of lime (which need not be so white as for the manufacture of white paint)
is added '8 lbs. of brown sugar, 1 quart of molasses, 8 lbs. of whiting, 2 lbs. of
dry white lead, both in fine powder, 14 lbs. of French ochre (mixed with water);
3 quarts of salt, and 8 ozs. of borax. The composition should be allowed to stand
for 10 or 12 hours before passing it through the mill. To produce venetian
red paint, the same proportions are employed as for yellow paint, with the
exception, that in place of the French ochre 9 lbs. of venetian red is added; by
increasing the quantity of venetian red and decreasing the quantity of whiting
a brighter red is obtained. To produce black paint, the process is similar to
that employed for the yellow and red, except that there is substituted for the
coloring pigments 4 lbs. of lamp black.
From the description above given it will readily be understood, that by
employing different pigments paints of any desired tint may be prepared.
It is only necessary to remark, that for bright colors the proportion of whiting

page_text: and white lead should be considerably reduced, and the quantity of the pigment
employed should be augmented in a corresponding degree. When required
for use the paints are reduced to a suitable consistency by the addition of
water.
If work coated with paint prepared according to this Invention is to be
varnished, it is preferred to employ a varnish prepared in the following
manner: To one gallon of linseed oil there is added one quart of spirits of
-turpentine and one pound of white resin; the mixture is allowed to stand
until the resin is entirely dissolved, and the varnish is then ready for use. In
order to improve the finish of the work, it is in some cases desirable to mix
this varnish with the last coat of paint; 1 lb. of varnish to 10 lbs. of paint is a
suitable proportion; the paint for the last coat should be very thin.
Having thus described the nature of the Invention, and the manner of
'performing the same, I would have it understood that I do not confine myself
to the exact details described; but what I claim is, the compounding lime
with sugar and molasses, and also with white lead and other pigments and
substances, as herein described, so as to produce paints.
In witness whereof, I, the said Patrick Robertson, have hereunto set
my hand and seal, this Nineteenth day of July, in the year of our
Lord One thousand eight hundred and fifty-eight.
'Witness,
JNO. ALCOCK.
PAT ROBERTSON. (L.S.)