Year: 1899

page_text: Date of Application (in United Kingdom), 9th Oct., 1899
Complete Specification Left, 9th July, 1900-Accepted, 18th Aug., 1900
I, THOMAS JOIN O'SULLIVAN, of the City of London, in the County of Middle-
sex, and Province of Ontario, Canada, Tinsmith, do hereby declare the nature
of this invention to be as follows:-
This invention relates to a new process of making dry pigment to be mixed
with oil to form paint, and it has for its object the production of a paint which
will be cheap to manufacture and of good quality.
The process consists in saturating sawdust with a salt of iron and then drying
and burning it; the residium forming the pigment.
For the salt of iron I use either of the following:-nitrate of iron, muriate
of iron sulphate of iron, phosphate of iron, or any other result of treating iron
with acid.
The solution may vary widely in strength, but I find a solution of from
six to fifty five per cent. "of the iron salt is best adapted to the purpose.
The wood sawdust is saturated with the solution, and the strength of the
solution is varied according to the shade or colour required; the less salt, the
darker the pigment.
After the sawdust has been saturated it is dried and burnt in direct con-
tact with the air. This is most conveniently effected by placing it in a wire
basket and starting a fire beneath it. The burning of the sawdust-when it
ignites will furnish the requisite heat.
The chemical changes are:-The expulsion of water and partial burning of
the carbon and a decomposition of the iron salt and its conversion into a red
oxide of iron mixed with the ash of the cellulose and more or less unconsumed
carbon.
The product is a friable mass of colour which varies from bright red to dark
brown which, when mixed with oil, forms a cheap and durable paint.
1900

page_text: I, THOMAS JOHN O'SULLIVAN, of the City of London, in the County of Middle-
sex, and Province of Ontario, Canada, Tinsmith, do hereby declare the nature
of this invention and in what manner the same is to be performed, to be particu-
larly described and ascertained in and by the following statement:---
My invention is in the nature of a new process of making dry pigment, which
is designed to be afterwards mixed with oil to form a paint.
It consists in saturating sawdust with a solution of a salt of iron and then
drying and burning it, the residuum forming the pigment.
For the salt of iron I may use nitrate of iron, muriate of iron, sulphate of
iron, or any other product obtained by treating iron with an acid. The solu-
tion may vary widely in strength; but I find a solution of from six to fifty-
five per cent. of the iron salt is best adapted to my uses.
To make the paint, I take a definite quantity of wood sawdust and saturate it
with a solution of the iron salt. The strength of the solution determines the
different shades of paint, the less iron salt to a given quantity of sawdust, the
darker will be the resulting pigment, and vice versa. After the sawdust has
been saturated with the solution it is dried, and burnt in direct contact with
the air. For this purpose it is only necessary to place it in a wire basket, start
a fire beneath it to dry out the moisture, and start the ignition, and then the
ignition of the sawdust, and conversion into the pigment proceeds
spontaneously after having been started-i.e. the burning of the sawdust
furnishes its own heat for the operation and the residuum left is the market-
able pigment. The chemical changes which takes place are the expulsion of
water from the sawdust and partial burning of the carbon and a decomposition
of the iron salt and its conversion into a red oxide of iron mixed with the ash
of the cellulose and more or less unconsumed carbon. The physical aspect of the
burned product is a powder or friable mass of a colour varying from light red
to dark brown, which forms a pigment, which, when mixed with oil forms a
very cheap and durable paint.
This pigment is very cheaply made, as the sawdust is practically a waste
material and in burning furnishes the necessary heat to complete the operation
after being dried out.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
The process of producing a pigment which consists in saturating sawdust with
a salt of iron and then drying it and burning it substantially as described.
Dated this 9th day of July 1900
P. R. J. WILLIS,
Agent for Applicant.