Dyeing and Printing.
Year: 1888

page_text: Date of Application, 26th June, 1888
Complete Specification Left, 27th Nov., 1888
Complete Specification Accepted, 31st Dec., 1888
Dyeing and Printing.
CHARLES DREYFUS of the Clayton Aniline Company Limited, Clayton near
Manchester, Chemist do hereby declare the nature of this invention to be as
follows:-
Primuline a yellow coloring matter forms when treated with nitrous acid a
diazo compound which when combined with beta Naphtol in an alkaline solution
produces a beautiful red color. This color is however of no use for dyeing or
printing purposes as it is very insoluble in water. I have however discovered a way
to make it soluble and a useful product for printing and dyeing purposes.
The production of the insoluble coloring matter is done in the usual way well
known to Chemists. The aqueous Primuline solution is first acidulated when a finely
divided precipitate is formed which is treated with nitrous acid, until the whole of it
is converted into its diazo compound. This body is then poured into an equivalent
solution of beta Naphtol in caustic soda, which is kept cool by means of ice and
which is well stirred and the formation of the coloring matter takes place at once.
This insoluble product is filtered, washed, pressed and dried.
To render it soluble 20 lb. of it are boiled for one hour at the reversed condenser
with 50 lb. of Bisulphite of Soda of about 50 Tw. The solution is then filtered from
impurities and the new product precipitated by means of common salt in form of a
yellow powder. This powder is very easily soluble in water. It is decomposed by
caustic alkalis and the original insoluble coloring matter is reproduced. When printed
on cloth and afterwards steamed the product is decomposed and the original red color
developed on the cloth. The thus produced color is very fast to boiling soap.
If Diazo Primuline is combined with alpha Naphtol, Resorcin and other similar
substances and the coloring matters are treated with Bisulphite of Soda in a similar
way to the one above described useful products are obtained which when printed on
cloth and afterwards steamed produce very fast maroons in the case of alpha
Naphtol and oranges in the case of Resorcin.

page_text: COMPLETE SPECIFICATION.
A Method for the Production of New Colouring Matters suitable for
Dyeing and Printing.
1 CHARLES DREYFUS of Daisy Mount Victoria Park Manchester in the County
of Lancaster Chemist do hereby declare the nature of this Invention and in
what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
Primulina a yellow colouring matter forms when treated with nitrous Acid a
diazo compound which when combined with Beta Naphthol in an Alkaline solution
produces a beautiful red colour. This colour has howover hitherto only boen
produced on the fibre and has not been available as a separate marketable product
or dye suitable for direct use for dyeing or printing purposes as it is very insoluble
in water. I have discovered a way to make it soluble and therefore a useful
marketable product for direct use for printing and dyeing purposes.
The production of the insoluble colouring matter is done in the usual way well
known to Chemists that is to say: the aqueous primuline solution is first acidulated
when a very finely divided precipitato is formed which is treated with nitrous acid
until the whole of it is converted into its dinzo compound. This mass is then
poured into an equivalent solution of beta-naphthol in caustic soda which is kept
cold by means of ice and which is well stirred and the formation of the colouring
matter takes place at once. This insoluble product is filtered washed pressed and
dried. To render it soluble it is heated (in a closed vessel or in a vessel in
connection with a reversed condensor) with the hi-sulphite of an alkali such as Soda
Potash or Ammonia or other base the bi-sulphite of which is soluble in water. I
do not limit myself to precise proportions or temperatures but I have obtained the
best results by taking 2 parts by weight of the insoluble colouring matter and
5 parts by weight of Bisulphite of Sodn of about 50° Twaddle and heating the
mixture to 212° Fahrenheit.
The solution is thon if necessary filtered from impurities and the new product
is precipitated in the form of a yellow or brownish yellow powder which
precipitation may be most economically effected by means of Chlorido of Sodium.
This powder is readily soluble in water. If treated with caustic alkali it is
decomposed and the original red insoluble colouring matter is reproduced.
When printed on fabrics and afterwards steamed the product is decomposed and
the original red colour developed upon the fabric. This colour so produced is
very fast against the action of soap solutions, when used in washing such fabrics.
If diazo primuline be combined with alpha-naphthol Resorcin and other similar
substances and the resulting colouring matters are treated with Bisulphite of an
alkali in the manner hereinbefore described, useful products are obtained which
when printed on cloth and afterwards steamed produce fast colours, these being for
instance maroons in the case of Alpha-naphthol and orange in the case of Resorcin.

page_text: 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.-
1st. The production of colouring matters suitable for dyeing and printing by
treating the insoluble colouring matters obtained as aforesaid with Bisulphite of an
alkali or of other base the Bi-sulphite of which is soluble in water substantially
as hercinbefore described.
2nd. The production of colouring matters suitable for dyeing and printing by
treating the insoluble colouring matters obtained as aforesaid by heating or
boiling them with Bisulphite of Soda in substantially the proportions hereinbefore
named.