IMPROVEMENTS IN THE MANUFACTURE OR EXTRACTION AND APPLICATION OF COLOURING MATTERS FROM THE PRODUCTS OF THE DISTIL- LATION OF COAL TAB
Year: 1860

page_text: LETTERS PATENT to Charles Cowper, of No. 20, Southampton Buildings,
Chancery Lane, in the County of Middlesex, Patent Agent, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OR EXTRACTION AND
APPLICATION OF COLOURING MATTERS FROM THE PRODUCTS OF THE DISTIL-
LATION OF COAL TAB."-A communication from abroad by Joseph Marie
Albert Battalier, residing at Avignon, in France.
Sealed the 1st March 1861, and dated the 4th October 1860.
PROVISIONAL SPECIFICATION left by the said Charles Cowper at the
Office of the Commissioners of Patents, with his Petition, on the
4th October 1860.
I, CHARLES COWPER, of No. 20, Southampton Buildings, Chancery Lane,
in the County of Middlesex, Patent Agent, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OR EXTRACTION
AND APPLICATION OF COLOURING MATTERS FROM THE PRODUCTS OF THE DISTILLA-
TION OF COAL TAR," to be as follows:-
The Invention relates to the extraction from some of the products of the
distillation of coal tar, of a red orange, or orange red, resinous matter insoluble
in water, and in producing from the same yellow and brown acids soluble in
water, and in the application of these substances, and their compounds or
derivatives to dyeing and printing.
To obtain the aforesaid resinous matter a quantity of the dry or solid pitch

page_text: resulting from the distillation of coal tar is placed in a retort of clay or other
suitable material, and heated by a furnace. The fire is increased until the
retort is red hot. A spongy carbon remains in the retort. The matter which
distils over towards the end of the operation, and which solidifies is the red
orange resinous matter herein-before mentioned. This resinous matter being
treated for two hours with three or four times its weight of strong ordinary
sulphuric acid or oil of vitriol produces a very soluble product. This is
neutralized by carbonate of lime and filtered, and a solution of the salt of lime
with the yellow acid is thus obtained. This solution, slightly acidulated, colours
silk yellow in the cold, and colours wool yellow with the aid of heat, and also
may be used for dyeing, printing, and staining other materials. The red
orange resinous matter being treated for twenty-four hours in the cold, with
fuming, sulphuric acid is dissolved. The product diluted with water and
neutralized by carbonate of lime and filtered gives a solution of the salt of lime
of the brown acid. This solution, slightly acidulated and heated, colours silk,
wool, and other substances of a red brown colour. It will be obvious that
other bases than lime may be used to combine with the yellow and brown
acids, and that various compounds of such acids may be made, and that other
colours may be mixed or combined with them. The proportions, times, and
temperatures also admit of variation.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by Edward Alfred Cowper, of 354, Great George Street, Westminster,
and Richard Anthony Thompson, of No. 1, Hornton Villas, Camden
Hill, Kensington, Executors of the last Will and Testament of the said
Charles Cowper, who departed this life on or about the 23rd day of
December 1860, in the Great Seal Patent Office on the 3rd April
1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, EDWARD
ALFRED COWPER, of 354, Great George Street, Westminster, and RICHARD
ANTHONY THOMPSON, of No. 1, Hornton Villas, Camden Hill, Kensington,
Executors of the last Will and Testament of Charles Cowper, late of No. 20,
Southampton Buildings, Chancery Lane, in the County of Middlesex, Patent
Agent, deceased, who departed this life on or about the Twenty-third day of
December, One thousand eight hundred and sixty, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of October, in the year of our Lord

page_text: One thousand eight hundred and sixty, in the twenty-fourth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto the
said Charles Cowper, Her special licence that he, the said Charles
Cowper, his executors, administrators, and assigns, or such others as he, the
said Charles Cowper, his 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 "IMPROVE-
MENTS IN THE MANUFACTURE OR EXTRACTION AND APPLICATION OF COLOURING
MATTERS FROM THE PRODUCTS OF THE DISTILLATION OF COAL TAR," a com-
munication to him from abroad by Joseph Marie Albert Battalier, residing at
Avignon, in France, upon the condition (amongst others) that he the said
Charles Cowper, his executors or administrators, by an instrument in
writing under his, 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 immediately after the
date of the said Letters Patent.
NOW KNOW YE, that we, the Edward Alfred Cowper and Richard
Anthony Thompson, as such executors as aforesaid, do hereby declare
the nature of the said Invention, and in what manner the same is to bo
performed, to be particularly described and ascertained in and by the fol-
lowing statement thereof, that is to say:-
The Invention relates to the extraction from some of the products of the
distillation of coal tar, of a red orange or orange red resinous matter insoluble
in water, and in producing from the same yellow and brown acids soluble in
water, and in the application of these substances and their compounds or
derivatives to dyeing and printing.
To obtain the aforesaid resinous matter a quantity of the dry or solid pitch
resulting from the distillation of coal tar is placed in a retort of clay or other
suitable material and heated by a furnace. The fire is increased until the
retort is red hot. A spongy carbon remains in the retort. The matter which
distils over towards the end of the operation, and which solidifies is the red orange
resinous matter herein-before mentioned. This resinous matter being treated
for two hours with three or four times its weight of strong ordinary sulphuric
acid or oil of vitriol produces a very soluble product. This is neutralized by
carbonate of lime and filtered, and a solution of the salt of lime with the yellow
acid is thus obtained. This solution slightly acidulated, colours silk yellow

page_text: in the cold, and colours wool yellow with the aid of heat, and also may be
used for dyeing, printing, and staining other materials. The red orange
resinous matter being treated for twenty-four hours in the cold, with fuming,
sulphuric acid is dissolved. The product diluted with water and neutralized
by carbonate of lime and filtered gives a solution of the salt of lime of the
brown acid. This solution slightly acidulated and heated colours silk, wool,
and other substances of a red, brown colour. It will be obvious that other
bases than lime may be used to combine with the yellow and brown acids, and.
that various compounds of such acids may be made, and that other colours may
be mixed or combined with them. The proportions, times, and temperatures
also admit of variation.
But in order that this Invention may be more readily understood we will
now more particularly describe the best manner of carrying the same into
effect.
The apparatus which is employed consists of a retort, by preference of cast
iron, placed over a furnace, which retort communicates with a chamber by
means of a tube, both the chamber and the tube being made of copper. This
chamber communicates with a second chamber by means of another tube, both
of which are also of copper. The first-named chamber is kept at a tempe-
rature of above three hundred degrees centigrade, the second chamber being
temperature. After half filling the crucible with pitch, tar, or
bitumen, the temperature of the same is gradually raised to a red heat, and all
the volatilizable portions of the pitch pass over into the chambers, while a
porous carbon remains in the retort. From the gaseous products of this
distillation the orange-red resinous matter is condensed and deposited in the
first chamber, while the other products, oils, paranaphtalines, &c., pass into the
second chamber. The aforesaid orange-red resinous substance is capable of
combining in at least two proportions with sulphuric acid. Thus, if it is mixed
at a temperature of eighty degrees centigrade with from 4 to 6 times its own
weight of monohydrous sulphuric acid diluted with water, and then neutralized
with carbonate of lime, it is resolved into two salts, one slightly soluble
which remains with the carbonate of lime, the other exceedingly soluble which
remains dissolved. To obtain the most soluble salt which is most readily used
we proceed in the following manner :-Monohydrous sulphuric acid as free as
possible from nitrous vapours and of sulphate of iron is heated in a water bath
in a glass or earthenware vessel to about ninety degrees centigrade. The
orange-red matter is then added little by little to the extent of about one-
ninth the weight of the acid, i.e., nine parts of sulphuric acid to one of the
orange-red matter, when it is found that by throwing a small quantity of this

page_text: mixture into water it is dissolved, the source of heat must be removed. To
promote the action of the acid on the colouring matter the mixture should be
continually stirred during the operation by means of a glass spatula. This
mixture diluted with water may be employed for dyeing wools, if neutralized,
by means of carbonate of soda a yellow dye is obtained corresponding with the
carmine of indigo. To obtain pure. yellows, principally for dyeing silks, the
dye must be purified in the following manner :-The mixture of the colouring
matter with sulphuric acid is diluted with water, it is then neutralized by
means of carbonate of lime. After having removed the sulphate of lime again
by washing and filtering, the yellow solution is heated to boiling point,
and small quantities of hydrate of lime are gradually added until it is found
that by pouring a small quantity of the yellow solution into a solution of proto-
chloride of tin a brown powder becomes precipitated. When the further
addition of hydrate of lime does no more improve the colour of the precipitates
it is discontinued, and the yellow solution is allowed to cool completely. After
separating from it the brown precipitate by filtering and washing, the yellow
solution is again heated to boiling point and is then acidulated with hydro-
chloric acid (muriatic acid) free from iron. A solution of albumen or gelatine
is then added in small quantities until it is found that the yellow solution,
when filtered and heated to boiling point, colours silks of a pure yellow. The
dye may be obtained either in the form of paste or in a solid form by precipi-
tating it either by means of hydrate of lime or magnesia, or by chloride of
calcium. A solution of protochloride of tin, either acid, or in the presence of
caustic soda, also precipitates the colouring matter in form of lake. To
obtain pure yellows the presence of salt of iron or of all other oxydising agents
must be avoided in the reagents. To obtain the derivative yellow-brown or
red-brown dyes, the orange-red matter is mixed with from fifteen to twenty
times its weight of fuming sulphuric acid (Nordhäuser), and after twenty-four
hours the mixture diluted with water may be used as a dye bath. The colour
of the derivatives may be carried to a brown by heating them when mixed with
an acid containing oxydizing agents, chromic or nitric acids, or binoxide of
manganese.
Having now described and ascertained the nature of the Invention, and
the manner in which the same is to be performed, we wish it to be under-
stood that what we claim is,―
Firstly, the production of the orange-red substance from the distillation of
coal tar, pitch, or bitumen.
Secondly, the production of the conjugated sulpho-derivatives of the

page_text: before mentioned orange-red substance by treating the same with sulphuric
acid.
Thirdly, the use of such before-mentioned orange-red substance or of its
yellow-brown or red-brown derivatives, either in a solid or a liquid state, either
soluble or insoluble, for the purpose of dyeing, printing, or staining all mineral,
vegetable, or animal matter in any shape or form, such as fibres, felts,
papers, &c.
In witness whereof, we, the said Edward Alfred Cowper and Richard
Anthony Thompson, have hereunto set our hands and seals, this
Second day of April, in the year of our Lord One thousand eight
hundred and sixty-one.
EDWARD ALFRED COWPER. (L.S.)
RICHARD A. THOMPSON.
(L.S.)
EDWARD ALFRED COWPER. (L.S.)
RICHARD A. THOMPSON.
(L.S.)