Improvements in Photographic Developers.
Year: 1896

page_text: Date of Application, 6th Jan., 1896
Complete Specification Left, 23rd Sept., 1896-Accepted, 14th Nov., 1895
PROVISIONAL SPECIFICATION.
Improvements in Photographic Developers.
I, ALEXANDER MELVILLE CLARK, of the Firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Chartered Institute
of Patent Agents, do hereby declare the nature of this invention (a communication
to me by Lembach and Schleicher of Biebrich-on-the-Rhine, Germany Chemical
Manufacturers,) to be as follows:-
This invention consists in the employment of hydrated oxy-quinolines and oxy-
tolu-quinolines, and of their substitution products, for developing photographic
impressions in halogen silver containing media.
Heretofore only those bodies have been known as organic developers from the
aromatic series, which contain in their essential structure at least two hydroxyl
groups, or at least two amido groups, or it may be hydroxyl and amido groups
together. The substitutes are in this connection either in the ortho, or in the para
position, whilst the meta-substitution products are wholly inoperative.
Of the quinoline series there have been heretofore proposed for use as photo-
graphic developers di-oxy-quinolines, di-amido-quinolines, and amido-oxy-quino-
lines, which have, however, not entered up till now into general use in photographic
work, because their complicated and tedious production have rendered them too
expensive whilst their developing power is considerably less than that of the
developers already in general use, such as rudinal, eikonogen, methol, hydro-
quinone, pyrogallol, etc.
The fact, however, that hydrated oxy-quinolines have also the power of
developing a photographic picture is entirely novel. It has been discovered by my
foreign correspondents that especially the tetra-hydro-compounds of the oxy-quino-
lines and oxy-tolu-quinolines, and also their "substitution" products (such for example
as tetra-hydro-ana-bromine-o-oxy-quinoline ((). Fischer & Renouf. Berichte der
Deutschen Chemischen Gesellschaft vol. 17 page 760); tetra-hydro-di-oxy-
quinoline (Bayer & Homolke. Berichte der Deutschen Chemischen Gesellschaft
vol. 16 page 2217); tetra-hydro-ana-amido-o-oxy-quinoline; tetra-hydro-o-oxy-
quinoline-aca-sulpho-acid; and tetra-hydro-o-oxy-quinoline carbo-acid (Schmidt &
Engelmann. Berichte der Deutschen Chemischen Gesellschalt-vol. 20 page 1219
and Heyden. Berichte der Deutschen Chemischen Gesellschaft-vol. 20 page 443)
are capable, by reason of their powerfully-reducing properties, of furnishing
photographic developers of high excellence which even when diluted to the utmost
cnceivable extent, develop the latent photographic picture in a perfectly clear and
extremely rapid manner and with sharpness of all details. Fogginess, such as is
usually produced by over-developing, has not been observed with their use.
As compared with the substitution products of oxy-quinoline proposed by
Auguste and Louis Lumière, ("Jahrbuch für Photographie and Reproductions-
teclk," 1892, page 93.) as photographic developers, these improved a idition-
products of oxy-quinoline or of oxy-tolu-quinoline, have the great advantage that
they possess a considerably greater developing power than the former, and that the
developing solutions prepared from them are extrem. ly durable and can be prepared
in a very concentrated condition.
In addition to the aforesaid hydrated oxy-quinolines and oxy-tolu-quin lines,
photographic developers of high excellence and great power are also constituted

page_text: by the hydrides of the oxy-quinolines and oxy-tolu-quinolines in substitution in
quinoline-nitrogen and also by the substances produced by the action of mono-
chlor-acetic-acid upon the hydrated oxy-quinolines and oxy-tolu-quin lines.
Of the substances coming in question in this connection, the following may be
mentioned :-
O-oxyhydromethyl quinoline (O. Fischer. Berichte der Deutschen
Chemischen Gesellschaft. vol. 16 page 714)
O-oxyhydro-ethylquinoline (O. Fischer. Berichte &c. vol. 16, page 717)
(Fischer & Renouf. Berichte &c. vol. 17, page 756)
O-oxyhydropropylquinoline (O. Fischer. Berichte &c. vol. 16, page 717)
O-oxy-hydro-butyl-quinoline (O. Fischer. Berichte &c. vol. 16,
page 717)
O-oxy bydro-amyl-quinoline (O. Fischer. Berichte &c. vol. 16, page 717)
O-oxyhydro-benzyl-quinoline (O. Fischer. Berichte &c. vol. 16,
page 717)
O-oxy-hydro-phenyl-quinoline
O-oxy-hydro-acetyl-quinoline
O-oxy-hydro-benzoyl-quinoline
O-oxy-hydro-methyl-quinoline-carbo-acid
(Schmidt & Engelmann. Berichte &c. vol. 20, page 1219).
Furthermore the corresponding compounds of p-oxy-quinoline hydride, and of
the oxy-tolu-quinoline hydrides; and also the products of reaction of mono-chlor-
acetic-acid upon o-oxy-quinoline hydride (Kairocoll, O. Fischer. Berichte &c.
vol. 16, page 719); p-oxy-quinoline hydride and oxy-tolu-quinoline hydrides.
In order to prepare the developing solution from the aforesaid compounds my
foreign correspondents proceed as follows:-
25 grammes of neutral sodium sulphite and 4 grammes of caustic potash are
dissolved with the aid of heat in 100 grammes of water and to this are added
10 grammes of tetra-hydro-o-oxy-quinoline or a corresponding amount of another
of the aforesaid substances.
Dated this 6th day of January 1896.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.
Improvements in Photographic Developers.
1, ALEXANDER MELVILLE CLARK of the Firm of A. M. and Wm. Clark of
53, Chancery Lane in the County of Middlesex, Fellow of the Chartered Institute
of Patent Agents, do hereby declare the nature of this invention (a communication
to me by Lembach and Schleicher of Biebrich-on-the-Rhine, Germany, Chemical
Manufacturers,) and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
This invention consists in the employment of hydrated oxy-quinolines and oxy-
tolu-quinolines and of their substitution products for developing photographic
impressions in halogen silver containing media.
Heretofore only those bodies have been known as organic developers from the
aromatic series which contain in their essential structure at least two hydroxyl
groups or at least two amido groups or it may be hydroxyl and amido groups
together. The substitutes are in this connection either in the ortho or in the para
position whilst the meta-substitution products are wholly inoperative.

page_text: Of the quinoline series there have been heretofore proposed for use as photo-
graphic developers di-oxy-quinolines, di-amido-quinolines, and amido-oxy-quinolines
shich have, however, not till now come into general use in photographic work
because their complicated and tedious production have rendered them too expensive
whilst their developing power is considerably less than that of the developers already
n general use such as rodinal, eikonogen, methul, hydroquinone, pyrogallol, etc.
The fact, however, that hydrated oxy-quinolines have also the power of developing
a photographic picture is entirely novel. It has been discovered that especially
he tetra-hydro-compounds of the oxy-quinolines and oxy-tolu-quinolines and also
heir "substitution" products (such for example as tetra-hydro-ana-bromine-o-oxy-
quinoline (O. Fischer & Renouf. Berichte der Deutschen Chemischen Gesellschaft,
ol. 17, page 760.); tetra-hydro-di-oxy-quinoline (Bayer & Homolke. Berichte
der Deutschen Chemischen Gesellschaft, vol. 16, page 2217.); tetra-hydro-ana-
amido-o-oxy-quinoline; tetra-hydro-o-oxy-quinoline-ana-sulpho-acid; and tetra-
ydro-o-oxy-quinoline carbo-acid (Schmidt & Engelmann. Berichte der Deutschen
Chemischen Gesellschaft, vol. 20, page 1219, and Heyden. Berichte der Deutschen
Chemischen Gesellschaft, vol. 20, page 443); are capable, by reason of their
powerfully reducing properties, of furnishing photographic developers of high
excellence which even when diluted to the utmost conceivable extent develop the
atent photographic picture in a perfectly clear and extremely rapid manner and
with sharpness of all details. Fogginess, such as is usually produced by over-
developing, has not been observed with their use.
As compared with the substitution products of oxy-quinoline proposed by Auguste
and Louis Lumière ("Jahrbuch für Photographie und Reproductions-technik,"
1892, page 93,) as photographic developers, these improved addition-products of
xy-quinoline or of oxy-tolu-quinoline have the great advantage that they possess
considerably greater developing power than the former, and that the developing
solutions prepared from them are extremely durable and can be prepared in a very
concentrated condition.
In addition to the aforesaid hydrated oxy-quinolines and oxy-tolu-quinolines,
photographic developers of high excellence and great power are also constituted
by the bydrides of the oxy-quinolines and oxy-tolu-quinolines in substitution in
quinoline-nitrogen and also by the substances produced by the action of mono-
chlor-acetic-acid upon the hydrated oxy-quinolines and oxy-tolu-quinolines.
Of the substances coming in question in this connection the following may be
nentioned:
O-oxyhyro-methyl quinoline (O. Fischer. Berichte der Deutschen
Chemischen Gesellschaft, vol. 16, page 714.);
O-oxyhydro-ethylquinoline (O. Fischer. Berichte der Deutschen
Chemischen Gesellschaft, vol. 16, page 717.);
(Fischer & Renouf. Berichte der Deutschen Chemischen Gesellschaft,
vol. 17, page 756.)
O-oxy-hydropropylquinoline (O. Fischer.
Berichte der Deutschen
Chemischen Gesellschaft, vol. 16, page 717.);
O-oxy-bydro-butyl-quinoline (O. Fischer. Berichte der Deutschen
Chemischen Gesellschaft, vol. 16, page 717.);
O-oxyhydro-amyl-quinoline (O. Fischer. Berichte der Deutschen
Chemischen Gesellschaft, vol. 16, page 717.);
O-oxy-hydro-benzyl-quinoline (O. Fischer. Berichte der Deutschen
Chemischen Gesellschaft, vol. 16, page 717).
O-oxy-hydro-phenyl-quinoline.
O-oxy-hydro-acetyl-quinoline.
O-oxy-hydro-benzoyl-quinoline.
O-oxy-hydro-methyl-quinoline-carbo-acid.
(Schmidt & Engelmaun. Berichte der Deutschen Chemischen Gesell-

page_text: Furthermore the corresponding compounds of p-oxy-quinoline hydride and of
the oxy-tolu-quinoline hydrides; and also the products of reaction of mono-chlor-
acetic acid upon o-oxy-quinoline hydride (Kairocoll O. Fischer. Berichte der
Deutschen Chemischen Gesellschaft vol. 16, page 719.); p-oxy-quinoline hydride
and oxy-tolu-quinoline hydrides.
In order to prepare the developing solution from the aforesaid compounds,
proceed as follows:-
25 grammes of neutral sodium sulphite and 4 grammes of caustic potash are
dissolved with the aid of heat in 100 grammes of water and to this are added
10 grammes of tetra-hydro-o-oxy-quinoline or a corresponding amount of another
of the aforesaid substances.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The use of hydrated oxy-quinolines and oxy-tolu-quinolines and also of their
substitution products in particular of the hydrides thereof in substitution in
quinoline nitrogen and also of the substances produced by the action of mono-chlor-
acetic-acid upon the hydrated oxy-quinolines and oxy-tolu-quinolines for developing
photographic pictures in halogen silver containing media.
2. A developer for photographic pictures which is prepared with the use of the
substances mentioned in Claim 1, consisting of a solution of tetra-hydro-o-oxy-
quinoline or of another of the before-mentioned substances, in an aqueous solution
of neutral sodium sulphite and caustic potash the concentrated durable solution
thus produced being diluted with water before use.
Dated this 23rd day of September 1896.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.