IMPROVEMENTS IN THE PRODUCTION OF ANILINE DYES
Year: 1875

page_text: LETTERS PATENT to Justus Wolff, of Wyke, near Bradford, Con-
sulting and Engineering Chemist, and Ralph Betley, of Wigan,
Analytical and Consulting Chemist, for the Invention of "IMPROVE-
Sealed the 23rd December 1875, and dated the 5th July 1875.
PROVISIONAL SPECIFICATION left by the said Justus Wolff and
Ralph Betley at the Office of the Commissioners of Patents,
with their Petition, on the 5th July 1875.
We, JUSTUS WOLFF, of Wyke, near Bradford, Consulting and
Engineering Chemist, and RALPH BETLEY, of Wigan, Analytical and
Consulting Chemist, do hereby declare the nature of our said Invention
for "IMPROVEMENTS IN THE PRODUCTION OF ANILINE DYES," to be as
follows:-
-
This Invention relates to the production of a series of dyes obtained
from a mixture of aniline or of toluidine, or mixtures of both, with or
without xylidine and nitro benzol or nitro toluol, or mixtures of both
may be employed with or without nitro xylol, or such combinations of

page_text: materials as may produce these mixtures, as, for example, nitro benzol,
tin, and hydrochloric acid. By treatment of these mixtures with certain
suitable metallic salts, either in crystals or in solution, as, for example,
protochloride of tin at a temperature of from about 190° to 220° Celsius
for a sufficiently long period, in order to develop the corresponding dyes, t
and then effecting their extraction with slightly acidulated water, either
in open vessels or under pressure, and precipitating either with salt,
caustic soda, or by other means.
If pure aniline and pure nitro benzol are treated with protochloride of
tin or other suitable metallic salts, according to this process, then a dye 1
is obtained which is soluble in water, and is capablo of dyeing directly
wool, cotton, or other textile fabrics of indigo blue shades from grayish
blue to blackish blue.
If the aniline contains toluidin and the nitro benzol contains nitro
toluol, then the colors obtained by this process will dye wool more or
less bluish black, pure black, redish black, and brownish black, the color
varying according to the quantity of toluidin and nitro toluol contained
in the mixtures.
In carrying out this Invention we give the following process as an
example:-First, we mix about 3 parts by weight of aniline (with about
2 parts by weight of protochloride of tin, and then add about one part
by weight of nitro benzol to the mixture); we then allow it to stand till
the first reaction is over, and we then heat it at about 200° to about 220°
Celsius until a sample drawn out and dropped into boiling water com-
municates to the boiling water a brownish yellow coloration. As soon
as this point is reached, which generally will take about 9 hours or
more, according to the proportions or quantities of the different sub-
stances which are contained in the mixture. The source of heat is then
to be removed, and the resulting mass, mclt, or product may then be
treated by a stream of steam, in order to remove the unattacked aniline,
and also any traces of diphenylamine and its homologues, which may
have been formed whilst this process was going on; or, in lieu of the
before-mentioned treatment, it may at once be submitted to the following
mode of extraction, which may be also adopted after having submitted
the product to a stream of steam :-Firstly, we boil for about half an
hour or an hour the product obtained, as before mentioned, three or four
times with a mixture, say, for example, of about one part by weight of

page_text: hydrochloric, or any other suitable acid, and with about 50 parts of water.
The thus yielded solution will contain traces of color and tin salt; from
which the oxide of tin can be recovered by precipitation with caustic
soda. After this we boil the remainder with slightly acidulated water
each time for about half an hour, so long as the water dissolves any
colour; we then filter these extractions, and precipitate either with salt
or with caustic soda, or by any other means. The thus yielded precipitate
is filtered off and dried, preferably with a small excess of hydrochloric,
or with any other suitable acid, and the thus obtained dyes are ready to
be used for dyeing purposes. These extractions we find are carried out
more advantageously by boiling and filtering under pressure.
The firstly resulted mass, product, or melt before it is steamed or after
steaming, as well as the extracted dye and the remainder or residue from
this extraction, may be used for preparing aniline varnishes of different
shades of colour.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Justus Wolff and Ralph Betley in the Great Seal
Patent Office on the 5th January 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JUSTUS
WOLFF, of Wyke, near Bradford, Consulting and Engineering Chemist,.
and RALPH BETLEY, of Wigan, Analytical and Consulting Chemist, send
greeting.
!
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of July, in the year
of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did for Herself, Her heirs and suc-
cessors, give and grant unto us, the said Justus Wolff and Ralph
Betley, Her special license, that we, the said Justus Wolff and
Ralph Betley, our executors, administrators, and assigns, or such
others as wc, the said Justus Wolff and Ralph Betley, our sexe-
cutors, administrators, or 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, usc,
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 OF ANILINE DYES," upon the condition
(amongst others) that we, the said Justus Wolff and Ralph Betley, our
executors or administrators, by an instrument in writing under our
hands and seals, should particularly describe and ascertain the naturo
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.
..1!
: NOW KNOW YE, that we, the said Justus Wolff and Ralph
Betley, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly, described
and ascertained in and by the following statement, that is to
VA.
say
5.
This Invention relates to the production of series of dyes obtained
from aniline or from aniline containing toluidine, either with or without
the addition of xylidine and nitro benzol or nitro toluol, or of nitro
benzol containing, nitro, toluol, or such combinations as may produce
these desired mixtures. By the treatment of these mixtures with certain
suitable metallic salts, such for example, as protochloride of tin, either
in crystals or in solution, as for example, protochloride-of-tin, such-mix-
tūres, as herein-after indicated, being submitted to a temperature of from
about 190° to 220° Celsius for a sufficiently long period, in order to pro-
duce the desired coloring matters, and then effecting their extraction
with water or with slightly acidulated water at an elevated temperature
either in open vessels or under pressure, and then precipitating the
coloring matters from solution either with salt, caustic soda, or by
other means.
:
.
I
If pure aniline and pure nitro benzol be treated with protochloride of
tin or other suitable metallic salts, according to our Invention, then a
dye or dyes are obtained, which. are soluble in water, and which are
capable of being employed for dyeing or printing upon wool, cotton, or
other textile fabrics, such dye. or dyes being of blue shades, and varying
from grayish blue to blackish blue, and to darker shades...
:

page_text: If the aniline contains toluidine, and the nitro benzol contains nitro
toluol, then the colors obtained by this Invention will dye wool more or
less bluish black, pure black, redish black, and brownish black, the color
varying according to the quantity of toluidine and nitro toluol contained
in the mixtures.
i
In carrying out this Invention we give the following process as an'
example: First, we mix about three parts by weight of aniline (with
about two parts by weight of protochloride of tin in crystals, or the
same amount of the salt in solution in water, and then add about one.
part by weight of nitro benzol to the mixture; we then allow it to
remain until the primary reaction is effected, and we then heat
the mixture to about from 200° to about 220° Celsius until a sample
drawn out and dropped into boiling water communicates to the boiling
water a brownish yellow coloration. As soon as this point is reached
the source of heat is then to be removed, and the resulting mass,
melt, or product may be treated either by steam or otherwise in order
to remove the excess of aniline, and also any traces of diphenylamine,
and its homologues which may have been formed; or, in lieu of the
before-mentioned treatment it may be at once submitted to the following
mode of extraction, which may be also adopted after having submitted
the product to the action of steam. The melt is then submitted to the
repeated action of water or of acidulated water at an elevated tempera-
ture until the solution becomes colored, that is to say, until the dye
produced becomes soluble. The solutions thus yielded will contain
traces of color and tin salt, from which the oxide of tin can be recovered
by precipitation with caustic soda. After this we boil the melt with
water, or with slightly acidulated water. The solution of the coloring
matters thus obtained we then filter, and precipitate the coloring matter
from it either with salt or with caustic soda, or by any other means.
The precipitate thus yielded is filtered off and dried, preferably with a
small excess of hydrochloric, or with any other suitable acid, and the
coloring matters thus obtained are ready to be used for the purposes of

page_text: The oxide of tin or other metal in the remainder or residue from the
extractions may be recovered by any suitable means.
Having now described and particularly ascertained the nature of our
said Invention, and the manner in which the same is or may be used
or carried into effect, we would observe in conclusion that what we
consider to be novel and original and therefore claim as the In-
vention secured to us by the herein-beforo in part recited Letters
Patent is, the production of a dye or of a series of dyes from aniline or
from toluidine, or from mixtures of the same, and cither with or without
the employment of xylidine, together with nitro benzol or nitro toluol or
mixtures of the same, in conjunction with metallic salts, as herein men-
tioned, in the manner and for the purposes as herein-before described.
In witness whereof, we, the said Justus Wolff and Ralph Betley,
have to this our Specification set our hands and seals, this
Fourth day of January, One thousand eight hundred and seventy-
six.