IMPROVEMENTS IN THE PRODUCTION AND APPLICATION OF A MATERIAL CALLED FRENCH PURPLE, AND IN THE PROCESS EMPLOYED IN OBTAINING IT
Year: 1858

page_text: LETTERS PATENT to William Spence, of 50, Chancery Lane, in the County
of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS IN THE
PRODUCTION AND APPLICATION OF A MATERIAL CALLED FRENCH PURPLE, AND IN
THE PROCESS EMPLOYED IN OBTAINING IT."-A communication.
Sealed the 29th June 1858, and dated the 1st May 1858.
PROVISIONAL SPECIFICATION left by the said William Spence at the
Office of the Commissioners of Patents, with his Petition, on the
1st May 1858.
I, WILLIAM SPENCE, of 50, Chancery Lane, in the County of Middlesex,
Patent Agent, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN THE PRODUCTION AND APPLICATION OF A MATERIAL CALLED FRENCH
PURPLE, AND IN THE PROCESS EMPLOYED IN OBTAINING IT," (being a communication
from abroad,) to be as follows:-
This Invention consists in a new process of manufacturing a product called
"French purple," which process may be described under the three following
heads:-
First, the preparation of the raw colour producing acids, (mixture of
evernic, lecanoric, orsellic, erythric acids, &c.)
Secondly, the change produced in these acids by the combined action of
ammonia, air, and heat, and their transformation into colouring matter.
And, thirdly, the treatment by means of which the colouring matter is
brought into a solid state.
As to the preparation of the raw acids.-This may be done by extracting
then directly from the lichens in various manners. It may be done by alcohol
with a subsequent distillation, in order to gather or collect on one hand the
acids, and on the other the alcohol which may serve for another operation; or

page_text: it
may be done by the acetic acid of commerce, which dissolves with heat a
great quantity of colour producing acids, and gives them up on cooling; or it may
be done by a mixture of alcohol and ammonia. The ulterior saturation of this
base by the acetic acid and the distillation then serve to separate the colour pro-
ducing acids, and to gather the alcohol employed. Or it may be done either with
or without heat, by means of water charged with a base or a basic salt, such as
ammonia, potash, soda, lime, barytes, strontian, carbonates, borates, phosphates
of potash, soda, or ammonia; in a word, by means of a compound capable of
forming, with the colour producing acids of the lichens, soluble salts, which,
when separated by filtration and pressure from the woody matter of these
lichens, are decomposed by sulphuric or hydrochloric acid in slight excess, so
as to set free the colour producing acids. The latter are gathered or collected
on strainers or filters washed with care, in order to separate the matters that
are soluble, and not suited for the formation of colour. Finally, this precipitate
is drained and dried naturally or artificially more or less according to need.
When ammonia is used the operation is as follows:-This base is encreased
by 5 or 6 times its volume of water, and a reasonable amount of extraction is
proceeded with, which is effected in such a manner that the ammoniacal
liquors may be first brought in contact with the lichens that are almost
exhausted, and finally poured upon the pure or fresh lichens, whence they will
become saturated with colour producing acids.
Into the liquors resulting from the treatment is poured sulphuric or hydro-
chloric acid, until they will give a strong red color to litmus paper. Thus is
formed an abundant precipitate, which is gathered or collected, washed, &c.
When for ammonia is substituted a milk of lime, it is necessary to excite this
latter base at a suitable temperature, then, the reaction being effected, to filter,
express, and decompose by hydrochloric acid in slight excess, afterwards to
gather or collect the precipitate, and wash it with care, in order to remove the
lime, for the presence of this base during the change of the acids is opposed to
the formation of the required colour.
Finally, the colour producing acids are otherwise prepared by boiling the
lichens in water sharpened with sulphuric or hydrochloric acid, in the proportion
of about 20 to 25 "grammes" (French measure) of these acids to the "litre"
(French measure) of water; then there is a pouring off and washing, in order
to get rid of foreign matters, and thus are obtained the raw insoluble acids
mixed with the woody matter of the lichens.
For the change and required transformation of the acids, the precipitate
obtained by one or other of the processes above referred to is taken, and while
stirred is moistened with ammoniacal liquid in sufficient quantity to dissolve it.

page_text: This is then boiled, and thus is obtained a liquor which soon passes into an
orange yellow, and which exposed to the air at a temperature of about 15 to 20
degrees, goes through the required changes by successively passing through a
series of shades, even to bright red.
When in this state the liquor is put into vessels which are very wide, and
consequently open to the air, in layers of about 10 to 12 "centimetres"
(French measure) at the most; these are gradually heated to a temperature of
about from 40 to 60 degrees. After several days the change is complete, which
may be ascertained by the purple violet tint which the liquor presents, and
especially by the chemical qualities of the colouring matter, viz., in being
insensible to weak acids in dying tissues of silk or wool without the aid of any
other agent, in shades unalterable by the air, in being capable of becoming
fixed on vegetable fibres, by means of the intervention of metallic oxydes, in
order to possess the property of uniting with certain colours, the union of which
with the fibre can only take place by the combination of the acids.
When instead of the separated raw acids, lichens purified by an acid are
employed, the process is still carried on by the use of ammonia, and the first
phase of the change (the formation of the red colour) is realized without
separating the woody matter of the lichens. But before proceeding to the
second phase of the operation, which requires a high temperature, care must
be taken to filter and express the lichens. The operation is finished on the
liquors.
As to the mode of proceeding in order to bring the colouring matter into a
solid state. As soon as the transformation of the acids is finished, the liquors
which hold the colouring matter in solution are to be reunited and saturated
with sulphuric, tartaric, or other acid. An abundant flaky kind of precipitate
is formed, which is gathered on a filter so as to be afterwards washed, carefully
drained, and dried. This precipitate, of a fine intense garnet colour, contains
the colouring matter in its purest state; it is only accompanied with a certain
quantity of an ammonical salt, with which it became impregnated at the time
of its precipitation. It is thus applicable to all operations of dyeing & printing,

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of May, 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 William Spence, Her special license that I, the said William Spence,
my executors, administrators, and assigns, or such others as I, the said
William Spence, 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 PRODUCTION AND APPLICATION OF A MATERIAL CALLED FRENCH PURPLE, AND IN
THE PROCESS EMPLOYED IN OBTAINING IT," being a communication from abroad,
upon the condition (amongst others) that I, the said William Spence, by an
instrument in writing under my hand and seal, 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 I, the said William Spence, do hereby declare the
nature of the 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 (that is to say):
:-
This Invention of "Improvements in the Production and Application of a
Material called French Purple, and in the Process Employed in Obtaining it,"
consists in a process of manufacturing a new product called "French
purple," which process is herein-after described under the three following
heads, viz.,
First, the preparation of the raw colour producing acids, (mixture of
evernic, lecanoric, orsellie, erythric acids, &c.)]
Secondly, the change produced on these acids by the combined action of
ammonia, air, and heat, and their transformation into colouring matter.
And, thirdly, the treatment by means of which the colouring matter is
brought into a solid state.
As regards the preparation of the raw acids. This may be done by extract-
ing them directly from the lichens in various manners; it may be done by
alcohol with a subsequent distillation, in order to gather or collect on the one
hand the acids, and on the other the alcohol which may serve for a new
operation (Robiquet); or it may be done by the acetic acid of commerce,

page_text: which, with heat, dissolves a great quantity of colour producing acids, and
gives them up on cooling; or it may be done by a mixture of alcohol and
ammonia. The ulterior saturation of this base by the acetic acid, and the
distillation, then serve to separate the colour producing acid, and to gather
the alcohol employed. Or it may be done either with or without heat, by
means of water charged with a base or a basic salt, such as ammonia, potash,
soda, lime, barytes, strontia, carbonates, borates of potash, soda, or ammonia ;
in a word, by means of a compound capable of forming, with the colour pro-
ducing acids of the lichens, soluble salts, which, when separated by filtration and
pressure from the woody matter of these lichens, are decomposed by sulphuric
or hydrochloric acid in slight excess, so as to set free the colour producing
acids. The latter are gathered or collected on strainers or filters, washed with
care, in order to separate the matters that are soluble and not suited for the
formation of colour; finally, this precipitate is drained and dried, naturally or
artificially, more or less, according to need.
When ammonia is used the operation is as follows:-This base is increased
by five or six times its volume of water, and a reasonable amount of exhaustion
is proceeded with, which is effected in such a manner that the ammoniacal
liquors may be first brought in contact with the lichens that are nearly ex-
hausted, and finally poured upon the pure or fresh lichens, whence they will
become saturated with colour producing acids. Into the liquors resulting from
this treatment is poured sulphuric or hydrochloric acid, until they will give a
strong red colour to litmus paper. Thus is formed an abundant precipitate,
which is gathered or collected, washed, &c..
When for ammonia is substituted a milk of lime it is necessary to excite
this latter base at a suitable temperature; then the reaction being effected, to
filter, express, and decompose, by hydrochloric acid in slight excess, afterwards
to gather or collect the precipitate, and wash it with care, in order to remove
the lime, for the presence of this base during the change of the acids is opposed
to the formation of the required colour. Finally, the colour producing acids
are otherwise prepared by boiling the lichens in water, sharpened with
sulphuric or hydrochloric acid in the proportion of about twenty to twenty-five
grammes" (French weight) of these acids to the "litre" (French measure)
of water; this is followed by pouring off and washing, in order to get rid of
foreign matters; and thus are obtained the raw insoluble acids mixed with the
woody matter of the lichens.
For the change and required transformation of the acids, the precipitate
obtained by one or other of the processes above referred to, is taken, and while
being stirred is moistened with ammoniacal liquid in sufficient quantity to

page_text: dissolve it; this is then boiled, and thus is obtained a liquor which soon passes
into an orange yellow, and which, exposed to the air at a temperature of about
fifteen to twenty degrees, becomes changed or transformed as required, by
When in
successively passing through a series of shades, even to bright red.
this state, the liquor is put into vessels which are very wide, and in consequence
open to the air in layers of about ten to twelve "centimètres" (French measure)
at the most; these vessels are gradually heated to a temperature of about from
forty to sixty degrees. After several days the change or transformation is
complete, which may be ascertained by the purple violet tint which the liquor
presents, and especially by the chemical qualities of the colouring matter, viz., in
being insensible to weak acids, in dyeing tissues of silk or wool, without the aid
of any
other agent in shades unalterable by the air, in being capable of becoming
fixed on vegetable fibres by means of the intervention of metallic oxydes, in
order to possess the property of associating or blending with certain colours
the union of which can only take place by the combination of acids. When,
instead of the raw acids, lichens purified by an acid are employed, the process
is still carried on by the use of ammonia, and the first phase of the change
(the formation of the red colour) is realised without separating the woody
matter of the lichens; but before proceeding to the second phase of the opera-
tion, which requires a high temperature, care must be taken to filter and
express the lichens. The operation is finished on the liquors.
As to the mode of proceeding in order to bring the colouring matter into a
solid state. As soon as the transformation of the acids is finished, the liquors
which hold the colouring matter in solution are to be reunited and saturated
with sulphuric, tartaric, or other acid. An abundant flaky kind of precipitate
is formed, which is gathered on a filter, so as to be afterwards washed carefully,
then drained and dried. This precipitate of a fine deep garnet colour contains
the colouring matter in its purest state; it is only accompanied with a certain
quantity of an ammoniacal salt, with which it became impregnated at the time
of its precipitation; it is thus applicable to all operations of dyeing and
printing.
Having thus described the nature of the said Invention communicated to
me, as aforesaid, and in what manner the same is to be performed, I would
have it understood that what I claim under the above in part recited Letters
Patent is,
First, the separation from the orcine or colouring principle of orchils, of a
colouring matter not hitherto used, which resists the action of the air and acids,
and which has been herein-before called "French purple," by reason of the
bright shades or tints which it is capable of imparting to tissues. This

page_text: colouring matter is characterised by the pure mallow, daisy, and dahlia shade
or tint which it gives naturally on silk by the addition of a weak acid; also by
the pure violet shade or tint to which it gives rise when uniting with the
carmine of indigo; finally, by the red shades or tints imitating those obtained
by murexide when in dyeing carthamus, cochineal or other red colouring
matters are made to intervene.
Secondly, I claim the manner in which, by means of this colour, are pro-
duced complex colours, which orchils, the extracts of orchil, and even orchil
generally are incapable of producing.
ミ
Thirdly, I claim the formation of this coloring matter, and the process by
the aid of which it is formed, extracted, and brought to a state in which it may
be preserved without change, as described.
As the formation of the purple colouring matter herein-before described
depends in its nature on the combination or union therewith of ammonia, air,
and heat, I claim the several processes having for their result the useful
employment of these agents in an economical, hygienic, and industrial point
of view.
I claim, also, not only the product and processes herein-before described,
but also their several applications, the several preparations of orchil liquid or
solid having the property of resisting the action of weak acids, and which
would contribute to the formation of complex colours having the characteristics
above described.
I also claim the application of these products to dyeing, and to the printing
of all the materials, fibres, or tissues capable of receiving them.
In witness whereof, I, the said William Spence, have hereunto set my
hand and seal, the Twenty-ninth day of October, in the year of our
Lord One thousand eight hundred and fifty-eight.
Witness,
GEO. BEDELL COULCHER,
Law Stationer,
50, Chancery Lane.
WILLIAM SPENCE. (L.B.)