A NEW BLUE DYE OR COLOURING MATTER
Year: 1873

page_text: LETTERS PATENT to Charles Denton Abel, of No. 20, Southampton
Buildings, Chancery Lane, in the County of Middlesex, for the
Invention of "A NEW BLUE DYE OR COLOURING MATTER."-A com-.
munication from abroad by Robert Gottheil, of Berlin, in the
Kingdom of Prussia, Civil Engineer and Chemist.
Sealed the 6th March 1874, and dated the 19th September 1873.
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel at
the Office of the Commissioners of Patents, with his Petition, on
the 19th September 1873.
I, CHARLES DENTON ABEL, of No. 20, Southampton Buildings,
Chancery Lane, in the County of Middlesex, do hereby declare the
nature of the said Invention for "A NEW BLUE DYE OR COLOURING
MATTER," to be as follows:-
This Invention relates to the preparation of a new blue dye or.
colouring matter, which the Inventor names violacein; it is distinguished
from the aniline dyes by being insoluble in water, alkalies, or alcohol, it
is not effected by light, and it resembles indigo blue so closely in its

page_text: properties that it is distinguishable therefrom only by the colour of its
solution in acids.
In preparing this colouring matter tar is distilled, the oils produced
are neutralized by an alkali till they give a weak alkaline reaction, they
are then washed with water and again subjected to distillation.
Those oils which contain carbolic acid, creosote, or naphthaline, and
which distil at a temperature exceeding 350° Fahrenheit are employed,
the carbolic acid or creosote is removed by weak lye, and then the oils
are combined with strong caustic lye of alkali or alkaline earth, and
subjected to higher oxydation by any known oxydising means.
A dye
stuff or colouring matter is thus produced which being separated by
filtration and throughly purified by washing is dissolved in an acid,
filtered, and again precipitated by the addition of potash, soda, or
ammonia, freed from any residuary oil by alcohol, and dried. The dye
thus purified furnishes a dark blue fast colour with a glance of coppery
red, or, when completely purified, of yellow. It is insoluble in alkalies,
ammonia, soap, or alcohol, it completely resists the action of light, it is
soluble in dilute acids, giving a red coloured solution, from which a
precipitate of a fine indigo blue colour is produced on the addition of an
alkali.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charles Denton Abel in the Great Seal Patent
Office on the 10th March 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
DENTON ABEL, of No. 20, Southampton Buildings, Chancery Lane, in 1
the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria by Her
Letters Patent, bearing date the Nineteenth day of September, in the
year of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Charles Denton Abel, Her special license
that I, the said Charles Denton Abel, my executors, administrators,
and assigns, or such others as I, the said Charles Denton Abel, my
executors, administrators, and assigns, should at any time agree with,

page_text: 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 "A NEW BLUE
DYE OR COLOURING MATTER," a communication to me from abroad by
Robert Gottheil, of Berlin, in the Kingdom of Prussia, Civil Engineer
and Chemist, upon the condition (amongst others) that I, the said
Charles Denton Abel, 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 immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Charles Denton Abel, 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 relates to the preparation of a new blue dye or colouring
matter which the Inventor names "violacein." It is distinguished
from the aniline dyes by being insoluble in water, alkalies, or alcohol, it
is not affected by light, and it resembles indigo blue so closely in its
properties that it is distinguishable therefrom only by the colour of its
solution in acids.
In preparing this colouring matter tar is distilled, the oils produced
are neutralized by an alkali till they give a weak alkalino reaction, they
are then washed with water and again subjected to distillation.
Those oils which contain carbolic acid, creosote, or napthaline, and
which distil at a temperature exceeding 350° Fahrenheit are employed,
the carbolic acid or creosote is removed by weak lye, and then the oils
are combined with strong caustic lye of alkali or alkaline earth, and
subjected to higher oxydation by any known oxydizing means.
A dyc
stuff or colouring matter is thus produced, which being separated by
filtration and thoroughly purified by washing, is dissolved in an acid,
filtered and again precipitated by the addition of potash, soda, or
ammonia, freed from any residuary oil by alcohol, and dried. The die
thus purified furnishes a dark blue fast colour with a glance of coppery
red, or, when completely purified, of yellow. It is insoluble in alkalies,

page_text: ammonia, soap, or alcohol, it completely resists the action of light, it is
soluble in dilute acids giving a red coloured solution from which a
precipitate of a fine indigo blue colour is produced on the addition of an
alkali.
Having thus described the nature of the said Invention, and in what
manner the same is to be performed, as communicated to me by my
foreign correspondent, I claim, the use of a blue dye or colouring matter
prepared by neutralizing by alkali, washing, and distilling certain oils
resulting from the distillation of tar, treating the product with alkali
and oxydizing the same, filtering, washing, and dissolving it in acid, and 1
precipitating the dye or colouring matter from the solution by the
addition of alkali, substantially as herein described.
In witness whereof, I, the said Charles Denton Abel, have hereunto
set my hand and seal, this Sixth day of March, in the year of
our Lord One thousand eight hundred and seventy-four.
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