Improved Process of Making Solid and Friable Colouring Matters from Logwood Extract and other Dye-wood Extracts.
Year: 1893

page_text: Date of Application, 18th Dec., 1893
Complete Specification Left, 18th Sept., 1894-Accepted, 20th Oct., 1894
PROVISIONAL SPECIFICATION.
Improved Process of Making Solid and Friable Colouring Matters
from Logwood Extract and other Dye-wood Extracts.
I, PERCY RICHARD JULIUS WILLIS, of 55 Chancery Lane, in the County
of London, Consulting Engineer, do hereby declare the nature of this invention
(a communication to me from abroad by William J. Matheson, on behalf of
William J. Matheson & Co. Limited, of 178 Front Street, New York, U.S.A.,
Dyers,) to be as follows:-
Logwood extract of about 70° Twaddle is heated to about 150° Fahrenheit and
mixed thoroughly with about seven per cent. of ammonium carbonate, previously
dissolved in as small amount of water as possible. The mixture is then poured or
ladled into shallow trays or pans, or other suitable receptacles, and allowed to stand
for several hours at room temperature of about 70° Fahrenheit, in order to rise and
set. An hour is usually sufficient for the crust to form, but it is advisable to let
the trays stand for several hours, so that the mass may rise as much as possible,
and become light, porous and spongy, while the crust becomes hard and set. The
receptacle and its contents is then placed in a suitable drying apparatus and the
mass is then allowed to dry at a temperature of 150° to 180° Fahrenheit. Increased
temperature hastens the drying, but I have obtained the most satisfactory results
in color brittleness and evenness of product by drying at the temperature above
stated. After the drying has taken place, the mass which is obtained is brittle,
and can be easily ground to powder, is not affected by atmospheric moisture and
dyes chromed wool in the same way as cured chip logwood. It is soluble in both
cold and hot water.
Dated this 18th day of December 1893.
COMPLETE SPECIFICATION.
Improved Process of Making Solid and Friable Colouring Matters
from Logwood Extract and other Dye-wood Extracts.
I, PERCY RICHARD JULIUS WILLIS, of 55 Chancery Lane, in the County
of London, Consulting Engineer, do hereby declare the nature of this invention
(a communication to me from abroad by William J. Matheson, on behalf of
William J. Matheson and Co. Ltd., of 178 Front Street, New York, N.Y., U.S.A.,
Chemists,) and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
In a Patent granted to W. J. Matheson No. 2316 Feby. 2nd 1893, and
entitled "A coloring matter obtained from logwood, and the process of producing
same," the objections to the various extracts of logwood usually met on the market
as well as the advantages of the product produced by the process of that Patent
are described at length.
The product produced by the process of the Patent hereinbefore mentioned
requires the use of a small amount of acetic acid, or other weak acid, when the
dye is used for dyeing on chromed wool, but in certain cases particularly when the
fabric to be dyed contains cotton fibres previously dyed with dyes easily affected
by acids, the subsequent use of an acid in the dye bath is objectionable.
11

page_text: By continued experimenting I have now found that it is possible to produce a
dry, friable colouring matter from logwood extract, by heating it with ammonium
carbonate, which possesses the same properties as the product produced by heating
logwood extract with an alkali nitrite, but which does not require the addition of
an acid when dyed on chromed wool, and which is of still greater tinctorial strength
than the former product.
I have found that by mixing hot extract of logwood of high gravity with
ammonium carbonate, which is also known as sesqui carbonate of ammonia or with
bi-carbonate of ammonia and allowing the mixture to stand several hours, whereby
the mass rises owing to the developement of gaseous bubbles, and their entangle-
ment in the viscous mass, the phenomenon being analogous to the rising of dough
by the action of yeast or baking powder, and finally heating the porous, spongy
mass thus formed until dry, a product is obtained, which has the properties
herein before mentioned.
The gas which causes the mass to rise consists largely of carbon dioxid.
1 am aware that aqua-ammonia has been used in conjunction with air to oxidize
thin logwood liquors, and that Cocchenhausen in particular has suggested a method
of oxidizing thin logwood liquors by making them alkaline with aqua-ammonia and
forcing air through them. This method however, aims only at the oxidation of
the haematoxylin dissolved in the thin liquor to haemateine and has nothing to do
with my process which has not the oxidation of the coloring matter of the extract
as its main object, but aims to convert the viscous or pitchy extracts into a dry,
friable and permanent solid. It has also been urged against the suggested method
of Cocchenhausen that its application on a large scale would be impracticable, as
the action of the oxygen of the air on a hot ammoniacal thin logwood liquor, does
not stop at the oxidation of the haematoxylin into haemateine, but continues
whereby the haemateine is also oxidized and passes into substances of a different
Dature, which are inferior or worthless as dyes. Hence it would be very difficult
and practically impossible to stop the oxidizing action of air on a large bulk of
hot thin logwood liquor at the point where oxidation has proceeded far enough,
and before it had attacked and injured the valuable colouring matter.
In the use of ammonium carbonate to effect the conversion of the viscous or
pitchy logwood extracts, oxidation of the coloring matter is not the main object
sought. The object is to so alter or destroy the viscous and resinous matters by
chemical action that it may become possible to convert the extract by heating into
a permanent and friable solid, which shall be practically soluble in cold water and
easily in hot water, and which shall be free from the objectionable properties of
the ordinary logwood extracts and which shall possess the tinctorial properties of
chip logwood in an intensified degree; and also to aid and accelerate the drying
of, the extract chemically altered, as above explained, by causing it to become
filled with bubbles of gas, which render it porous, spongy and light, and allow
of a rapid escape of moisture at the elevated temperature to which it is exposed.
My process for making a solid, brittle or friable coloring matter from logwood
is substantially as follows:-
Logwood extract of about 70° Twaddle is heated to about 150° Fahrenheit and
mixed thoroughly with about seven per centum of ammonium carbonate, previously
dissolved in as small an amount of water as possible. The mixture is then poured
or ladled into shallow trays cr pans, or other suitable receptacles, and allowed to
stand for several hours at room temperature, about 70° Fahrenheit, in order to
rise and set. An hour is usually sufficient for the crust to form, but it is advisable
to let the trays stand several hours, so that the mass may rise as much as
possible, and become light, porous and spongy, while the crust becomes hard and
set. The receptacle and its contents is placed in a suitable drying apparatus and
the mass is allowed to dry at a temperature of 150°-180° Fahrenheit.
Increased temperature hastens the drying, but I have obtained the most
satisfactory results in color, brittleness and evenness of product by drying at
the temperature above stated.

page_text: After the drying has taken place, the mass which is obtained is brittle, and
can be easily ground to powder, is not affected by atmospheric moisture and
dyes chromed wool in the same way as cured chip logwood.
It is practically soluble in cold water and easily in hot water.
The above method of procedure is the best to me known, but as heat and time
are frequently convertible conditions in chemical reactions, and the amounts of the
substances taken may vary depending on their strength, I do not limit myself to
the temperatures, nor to the exact gravities or proportions above set forth, the
essence of my discovery and invention being that when extract of logwood is
mixed with an ammonium compound under such conditions as to bring about a
chemical reaction between them, resulting in the alteration or destruction of the
resinous and viscous matters, and attended with the evolution of a gas which shall
cause the extract under the proper conditions of gravity and temperature to puff
up and become porous and spongy, a new product may be produced which is easily
dried and which has the characteristics herein before set forth.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1. In the art of making logwood extract, the improvement which consists in
adding to logwood extract ammonium carbonate in the presence of water, and
causing a reaction between the carbonate and the extract substantially as
described.
2. In the art of making logwood extract, the improvement which consists in
adding to logwood extract ammonium carbonates in the presence of water, causing
a reaction between the extract and the carbonate and evaporating the product to
dryness, substantially as described.
3. As a new article of manufacture a colouring matter derived from logwood
extract by the incorporation therewith of ammonium carbonate, and characterized
by the fact of its being a friable solid; soluble in cold and rapidly soluble in hot
water, substantially as described.
Dated this 18th day of September 1894.