U.S. patent number 3,691,210 [Application Number 04/703,197] was granted by the patent office on 1972-09-12 for 2-(omega-hydroquinonyl-alkyl)-anthraquinones.
This patent grant is currently assigned to Polaroid Corporation. Invention is credited to Warren E. Solodar.
United States Patent |
3,691,210 |
Solodar |
September 12, 1972 |
2-(OMEGA-HYDROQUINONYL-ALKYL)-ANTHRAQUINONES
Abstract
This application relates to the synthesis of compounds having
the formula: ##SPC1## Wherein each X is hydroxy or amino (including
secondary amino, e.g., alkylamino), and R is an alkylene radical,
preferably a lower alkylene radical containing 1-6 carbon atoms;
and to compounds having the formula: wherein R is the same as
above; as well as to the use of such compounds in photographic
developer compositions and developing processes. The compounds of
formula (A) are also suitable for use as dyes for textile
fibers.
Inventors: |
Solodar; Warren E. (Newton
Centre, MA) |
Assignee: |
Polaroid Corporation
(Cambridge, MA)
|
Family
ID: |
24824420 |
Appl.
No.: |
04/703,197 |
Filed: |
November 1, 1967 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
370345 |
May 26, 1964 |
|
|
|
|
Current U.S.
Class: |
552/245; 430/224;
430/250; 552/262; 562/478; 568/313; 568/325; 568/644; 568/723;
568/729 |
Current CPC
Class: |
C07C
49/255 (20130101); C07C 45/62 (20130101); C07C
45/62 (20130101); C07C 37/055 (20130101); C07C
45/74 (20130101); G03C 5/3021 (20130101); C07C
45/74 (20130101); C07C 37/055 (20130101); C07C
43/2055 (20130101); C09B 1/503 (20130101); G03C
8/18 (20130101); C09B 1/515 (20130101); C09B
1/06 (20130101); C07C 39/15 (20130101); C07C
49/255 (20130101); C07C 49/255 (20130101) |
Current International
Class: |
C07C
49/00 (20060101); C07C 37/00 (20060101); C07C
49/255 (20060101); C07C 37/055 (20060101); C07C
43/205 (20060101); C07C 43/00 (20060101); C07C
45/62 (20060101); C07C 45/00 (20060101); C07C
45/74 (20060101); C09B 1/515 (20060101); C09B
1/503 (20060101); C09B 1/06 (20060101); C09B
1/00 (20060101); G03C 8/18 (20060101); G03C
5/30 (20060101); G03C 8/02 (20060101); C07c
049/74 () |
Field of
Search: |
;260/380,383
;96/29D,66,55 |
Foreign Patent Documents
Other References
Lubs, Dyes and Pigments, 1955, pp. 338, 362..
|
Primary Examiner: Weinberger; Lorraine A.
Assistant Examiner: Gerstl; Robert
Parent Case Text
This application is a division of application Ser. No. 370,345
filed May 26, 1964, now abandoned.
Claims
What is claimed is:
1. A compound of the formula: ##SPC18##
wherein each X is a member of the group consisting of hydroxy and
amino radicals; and R is an alkylene radical having from one to six
carbon atoms.
2.
3. ##SPC19##
4. ##SPC20##
Description
This invention relates to photography and more particularly to
products, compositions and processes for the development of
photosensitive silver halide elements.
It is one object of the present invention to provide novel
processes and compositions for the development of silver halide
emulsions, in which novel developing agents are used.
Another object is to provide novel processes and compositions for
the development of silver halide emulsions, in which the novel
developing agent is capable of developing an exposed silver halide
emulsion and imparting a reversed or positive colored image of the
developed image to a superposed image-receiving material.
A further object is to provide novel silver halide developing
agents and novel products, processes and compositions suitable for
use in preparing monochromatic and multichromatic photographic
images.
Other objects of the invention will in part be obvious and will in
part appear hereinafter.
The invention accordingly comprises the processes involving the
several steps and the relation and order of one or more of such
steps with respect to each of the others, and the products and
compositions possessing the features, properties and the relation
of elements which are exemplified in the following detailed
disclosure, and the scope of the application of which will be
indicated in the claims.
Certain of the objects of this invention may be accomplished by the
use of novel dyes which have the ability to develop images present
in an exposed silver halide emulsion; thus they may be referred to
as dye developers. These novel dyes or dye developers will be
further described hereinafter.
For a fuller understanding of the nature and objects of the
invention, reference should be had to the following detailed
description.
The photographic processes and compositions disclosed herein are
particularly useful in the treatment of an exposed silver halide
emulsion, whereby a positive dye image may be imparted to another
element, herein referred to as an image-carrying or image-receiving
element.
U.S. Pat. No. 2,983,606, issued May 9, 1961 to Howard G. Rogers,
discloses diffusion transfer processes wherein a photographic
negative material, such as a photographic element comprising an
exposed silver halide emulsion, is developed in the presence of a
dye developer to impart to an image-receiving layer a reversed or
positive dye image of the developed image by permeating into said
emulsion a suitable liquid processing composition and bringing said
emulsion into superposed relationship with an appropriate
image-receiving layer. The inventive concepts herein set forth
provide novel dye developers for use in such processes.
In carrying out the process of this invention, a photosensitive
element containing a silver halide emulsion is exposed and wetted
with a liquid processing composition, for example by immersing,
coating, spraying, flowing, etc., in the dark, and the
photosensitive distribution superposed prior to, during or after
wetting, on an image-receiving element. In a preferred embodiment,
the photosensitive element contains a layer of dye developer, and
the liquid processing composition is applied to the photosensitive
element in a uniform layer as the photosensitive element is brought
into superposed position with an image-receiving element. The
liquid processing composition permeates the emulsion to provide a
solution of dye developer substantially uniformly distributed
therein. As the exposed silver halide emulsion is developed, the
oxidation product of the dye developer is immobilized or
precipitated in situ with the developed silver, thereby providing
an imagewise distribution of unoxidized dye developer dissolved in
the liquid processing composition. This immobilization is
apparently due, at least in part, to a change in the solubility
characteristics of the dye developer upon oxidation, and especially
as regards its solubility in alkaline solutions. It may also be
due, in part, to a tanning effect on the emulsion by the oxidized
developing agent. At least part of this imagewise distribution of
unoxidized dye developer is transferred, by imbibition, to a
superposed image-receiving layer. The image-receiving layer
receives a depthwise diffusion, from the emulsion, of unoxidized
dye developer, without appreciably disturbing the imagewise
distribution thereof, to provide a reversed or positive, colored
image of the developed or negative image. The image-receiving
element may contain agents adapted to mordant or otherwise fix the
diffused, unoxidized dye developer. Imbibition periods of
approximately one minute have been found to give good results, but
this contact period may be adjusted where necessary to compensate
for variations in temperature or other conditions. The desired
positive image is revealed by stripping the image-receiving layer
from the silver halide emulsion at the end of the imbibition
period.
The dye developers of this invention may be utilized in the
photosensitive element, for example in, on or behind the silver
halide emulsion, or they may be utilized in the image-receiving
element or in the liquid processing composition. In a preferred
embodiment, a coating or layer of the dye developer is placed
behind the silver halide emulsion, i.e., on the side of the
emulsion adapted to be located most distant from the photographed
subject when the emulsion is exposed and preferably also adapted to
be most distant from the image-receiving layer when in superposed
relationship therewith. Placing the dye developer behind the
emulsion layer, as in the preferred embodiment, has the advantage
of providing increased contrast in the positive image, and also
minimizes any light-filtering action by the colored dye developer.
In this preferred embodiment, the layer of dye developer may be
applied by using a coating solution containing about 0.5 to 8%, by
weight, of the dye developer. Similar concentrations may be used if
the dye developer is utilized as a component of the liquid
processing composition In an especially useful mode of disposing
the dye developers in the photosensitive elements, the dye
developer is dissolved in a water-immiscible solvent and then
dispersed in a gelatin coating solution.
The liquid processing composition which is used in the processes
herein disclosed comprises at least an aqueous solution of an
alkaline compound, for example, diethylamine, sodium hydroxide or
sodium carbonate, and may contain the dye developer. In some
instances, it may contain an additional silver halide developing
agent. If the liquid processing composition is to be applied to the
emulsion by being spread thereon, preferably in a relatively thin,
uniform layer, it may also include a viscosity-increasing compound
constituting film-forming material of the type which, when spread
over a water-absorbent base, will form a relatively firm and
relatively stable film. A preferred film-forming material is a high
molecular weight polymer such as a polymeric, water-soluble ether
inert to an alkali solution, as, for example, a hydroxyethyl
cellulose or sodium carboxymethyl cellulose. Other film-forming
materials or thickening agents whose ability to increase viscosity
is substantially unaffected when left in solution for a long period
of time may also be used.
The novel dye developers of this invention are anthraquinone dyes
having the formula: ##SPC2##
wherein each X is hydroxy or amino (including secondary amino,
e.g., alkylamino), and R is an alkylene radical, preferably a lower
alkylene radical containing one to six carbon atoms, such as
--CH.sub.2 --, --CH.sub.2 --CH.sub.2 --, --CH.sub.2 --CH.sub.2
--CH.sub.2 --,
--ch.sub.2 --ch.sub.2 --ch.sub.2 --ch.sub.2 --,
--ch.sub.2 --ch.sub.2 --ch.sub.2 --ch.sub.2 --ch.sub.2 --,
--ch.sub.2 --ch.sub.2 --ch.sub.2 --ch.sub.2 --ch.sub.2 --ch.sub.2
--, etc.
As examples of dye developers within the scope of Formula (A),
mention may be made of the following: ##SPC3##
It will be noted that the compounds of Formula (A), e.g., compounds
1-10, are new dye developers having a single developer moiety
linked to the anthraquinone dye nucleus in the 2-position by an
alkylene group.
The dye developers of this invention may be prepared by the steps
of: (1) reacting 3,6-dimethoxyphthalic anhydride: ##SPC4##
with a bis-hydroquinonyl compound of the formula: ##SPC5##
to form a dye developer of Formula (A) wherein each X is hydroxy,
which dye developer may be represented by the following formula:
##SPC6##
The dye developers of Formula (C) may be employed as disclosed in
the aforementioned U.S. Pat. No. 2,983,606 or they may be converted
to the 5,8-diamino analogue by (2) reducing the dye developer of
Formula (C) to its leuco form; and thereafter (3) reacting the
leuco derivative with ammonia or a suitable amine, e.g., an alkyl
amine, to form a dye developer of Formula (A), wherein each X is an
amino group, which dye developer may be represented by the formula:
##SPC7##
wherein X.sup.1 is a primary or secondary amino group.
The bis-hydroquinonyl compounds of Formula (B), which are also
useful as silver halide developing agents in black-and-white
photographic processes, may be prepared by reacting with
hydroquinone a compound of the formula: ##SPC8##
wherein n is a positive integer of at least 1, to provide the
requisite number of carbon atoms in the alkylene group of the dye
developer, e.g., a positive integer from one to seven, the reaction
being performed in the presence of a suitable catalyst such as
boron trifluoride, to form a compound of the formula: ##SPC9##
which is then hydrogenated in the presence of a suitable
hydrogenation catalyst such as palladium/carbon to form the desired
bis-hydroquinonyl compound of Formula (B).
As examples of useful compounds within the scope of Formula (E),
mention may be made of gentisic acid, homogentisic acid,
p-dihydroxyhydro-cinnamic acid,
.alpha.-methyl-2,5-dihydroxyhydrocinnamic acid,
.alpha.-ethyl-2,5-dihydroxyhydrocinnamic acid, etc.
Certain of the compounds of Formula (B) may also be formed, as
noted by Example (1), by reacting 2,5-dimethoxy-benzaldehyde or its
homologues with a suitable ketone such as acetone to form the
corresponding alpha, omega- bis-dimethoxyphenyl-di-unsaturated
ketone, which is then reduced and the methoxy groups hydrolyzed to
form the desired compound of Formula (B).
This latter synthesis, as applied to the synthesis of
1,5-bis-hydroquinonyl-pentane, may be illustrated by the following
equations: ##SPC10##
The following examples show by way of illustration and not by way
of limitation the preparation of the novel compounds of this
invention.
EXAMPLE 1
A mixture of 163.0 gm. of 2,5-dimethoxybenzaldehyde, 28.4 gm. of
acetone and 294.0 ml. of ethanol 3A was added portionwise over a
period of ten minutes to a well-stirred solution of 98.0 ml. of 50
percent sodium hydroxide in water, 882.0 ml. of water and 785.0 ml.
of ethanol 3A. The temperature was maintained in a range of
19.degree.-22.degree. C. during the entire reaction. The above
mixture was stirred for 1 hour. ?A precipitate began forming
approximately one-half hour after admixture.! The reaction mixture
was then allowed to stand for one-half hour without stirring, after
which it was filtered to obtain a yellow precipitate. This
precipitate was desiccated over KOH + P.sub.2 O.sub.5 in vacuo for
two days, after which it was recrystallized in 1500.0 ml. of a
50/50 benzene-hexane solution. 127.0 gm. (73 percent yield) of
yellow needle crystals were recovered by concentrating the solvent
at room temperature. This compound, 1,5-bis-(2'
,5'-dimethoxybenzal)-acetone, m.p. 105.degree.-106.degree. C., had
the following structural formula: ##SPC11##
11.87 gm. of this compound were dissolved in 100 ml. of hot ethanol
3A. 2.0 gm. of 10 percent Pd/BaSO.sub.4 were then added and the
resulting mixture was hydrogenated on a Parr shaker for 23 minutes.
After uptake of two equivalents of hydrogen, a white product
precipitated. 50.0 ml. of ethanol 3A were added and the mixture was
heated until solution was complete, after which the Pd/BaSO.sub.4
catalyst was filtered off. The solution was allowed to concentrate
at room temperature in a hood to obtain white flakes, m.p.
72.5.degree.-74.degree. C. Desiccation overnight over P.sub.2
O.sub.5 in vacuo yielded 9.73 gm. (80 percent yield) of
1,5-bis-(2',5'-dimethoxybenzyl)-acetone of the formula:
##SPC12##
12.75 gm. of the latter compound were added to a mixture of zinc
amalgam ?prepared by admixing 60.0 gm. mossy zinc and 6.0 gm.
HgCL.sub.2 ; adding 6.0 ml. of concentrated HCl and 160 ml. of
water; shaking at room temperature for 5 minutes; and then
decanting, the zinc amalgam being covered immediately after
preparation with 40.0 ml. of water, 60.0 ml. of acetic acid and
80.0 ml. of concentrated HCl !. The resulting mixture was refluxed
overnight and then allowed to cool. After cooling, the mixture was
extracted several times with ether. The ether extracts were washed
free of acid with a carbonate solution. The ether was dried over
MgSO.sub.4, filtered and evaporated. The residual oil crystallized
on seeding. Crystallization from 35.0 ml. of isopropyl alcohol gave
11.3 gm. of 1,5-bis-(2',5'-dimethoxyphenyl)-pentane, a white solid,
m.p. 46.degree.-47.5.degree. C., having no carbonyl band in the
I.R., and having the following formula: ##SPC13##
7.13 gm. of this compound, 75.0 ml. of 48% HBr, 5.0 ml. of
concentrated HCl and 120.0 ml. of glacial acetic acid were placed
in a 250 ml. RB flask, fitted with an adequate condenser, wrapped
in aluminum foil and refluxed for five hours. During the last hour
the condenser was fitted for downward distillation. Approximately
125 ml. of clear liquid came over at 100.degree.-115.degree. C.
After the liquid remaining in the reaction flask was cooled (some
precipitating occurred), 150 ml. of ether and 150 ml. of water were
added. The ether layer was collected and the water extracted two
more times with 50.0 ml. portions of ether. The combined ether
layers were treated with charcoal until no further color change was
noticed. The ether was then dried by the addition of anhydrous
MgSO.sub.4 and filtered. The evaporation of the ether on a steam
bath left a solid, tan-colored residue which was washed with 75.0
ml. of hexane, filtered and air-dried to yield 5.15 gm. (86 percent
yield) of 1,5-bis-hydroquinonyl-pentane, a light tan powder, m.p.
167.degree.-168.5.degree. C., of the formula: ##SPC14##
EXAMPLE 2
To a melt of 80.0 gm. of anhydrous aluminum chloride and 30.0 gm.
of sodium chloride at 190.degree. C. was gradually added in 30
minutes with thorough stirring, an intimate mixture of 5.9 gm. of
1,5-bis-hydroquinonyl-pentane (as prepared in Example 1) and 4.0
gm. of 3,6-dimethoxyphthalic anhydride. The resulting mixture was
heated to 220.degree. C. and stirring was continued for 45 minutes.
The mixture was then cooled to provide a solidified blue mass which
was pulverized in a mortar, then cautiously added in portions to
250.0 ml. of warm water containing 15.0 ml. of concentrated HCl
This formed a purple precipitate which was filtered off, washed
with hot water, and desiccated in vacuo over P.sub.2 O.sub.5. 7 gm.
(81 percent yield) of a crude product, m.p. 195.degree.-205.degree.
C., was obtained. Two crystallizations from acetic acid yielded
2-(omega-hydroquinonyl-pentyl)-1,4,5,8-tetrahydroxyanthraquinone, a
purplish powder, m.p. 153.degree.-155.degree. C., .lambda..sub.max.
at 560 m.mu.; .epsilon. = 18,400, having the following structural
formula: ##SPC15##
Analysis Calculated for C.sub.25 H.sub.22 O.sub.8 : Found: C = 66.6
H = 4.9 C = 67.0 H = 4.9
EXAMPLE 3
To a deaerated solution of 11.8 gm. of
2-(omega-hydroquinonyl-pentyl)-1,4,5,8-tetrahydroxyanthraquinone
(as prepared in Example 2) in 120.0 ml. of 2N KOH were added 5.8
gm. of freshly prepared zinc amalgam (prepared as in Example 1).
The resulting mixture was stirred and refluxed under nitrogen for 7
hours, adding a fresh charge of zinc amalgam after the fourth hour.
The reaction, after standing at room temperature overnight under
nitrogen, was continued for 2 hours longer the following morning,
adding a third charge of zinc amalgam. Progress of the reaction was
followed spectrally, observing the build-up of "leuco bands" at 456
and 484 m.mu.. The reaction was continued to the disappearance of
the peaks at 546 and 560 m.mu.. The mixture was then allowed to
cool, after which it was acidified to pH 5 by the gradual addition
of a deaerated mixture of 40 ml. of acetic acid and 70.0 ml. of
water. The brown precipitate that separated was filtered off and
desiccated to yield 10.8 gm. (91 percent) of the leuco form of the
tetrahydroxyanthraquinone starting material, a light brown solid,
m.p. 125.degree.-135.degree. C. A deaerated mixture of 9.04 gm. of
this leuco compound, 4.35 gm. of 3-aminopentane and 35.0 ml. of
dimethylformamide was stirred and heated on the steam bath under
nitrogen for 1 hour. 11.4 gm. of pyridine N-oxide were added and
the heating and stirring continued under nitrogen for seven hours
longer, following spectrally the build-up of the 625 and 679 peaks,
and the disappearance of the "leuco bands". A fresh charge of
pyridine N-oxide was added and the oxidation continued an
additional 18 hours. The mixture was acidified with 5.0 ml. of
acetic acid and poured into 500.0 ml. of dilute HCl. The
precipitate that separated was filtered off and desiccated in vacuo
over P.sub.2 O.sub.5, yielding 9.4 gm. of a blue solid. This solid
was purified by extraction with 250 ml. of benzene under nitrogen
for three hours. Evaporation of the benzene in vacuo gave
2-(omega-hydroquinonyl-pentyl)-1,4-dihydroxy-5,8-bis-.alpha.
-ethyl-propylamino-anthraquinone, a shiny blue solid,
.lambda..sub.max. at 681 and 626 m.mu. in methyl cellosolve;
.epsilon..sub.681 = 32,600 and .epsilon..sub.626 = 21,400, and
having the following structural formula: ##SPC16##
EXAMPLE 4
Substitution of 2-amino-butane for 3-aminopentane in the process of
Example 3 yielded a blue solid,
2-(omega-hydroquinonyl-pentyl)-1,4-dihydroxy-5,8-bis-.alpha.-methyl-propyl
amino-anthraquinone, having the same .lambda..sub.max. as the dye
developer prepared in Example 3, and having the following formula:
##SPC17##
In Examples 2, 3 and 4, analysis of the proton magnetic resonance
spectra indicated that the amino substituent was substituted in the
5,8-positions, as shown by the structural formulae, rather than in
the 1,4-positions.
The following examples illustrate the use of the novel
bis-hydroquinonyl developing agents of this invention in the
preparation of black-and-white images.
EXAMPLE 5
A photosensitive element was prepared by coating a gelatin
subcoated film base at a speed of 10 feet/minute with a solution
comprising 1.8 gm. of 1,5-bis-hydroquinonyl-pentane and 0.5 percent
cellulose acetate hydrogen phthalate in 75 cc. of ethanol and 25
cc. of acetone. After this coating had dried, a silver iodobromide
emulsion was coated on at a speed of 5 feet/minute and allowed to
dry. This photosensitive element was exposed for 1/100th of a
second and then developed by contacting the exposed photosensitive
element in the dark for 1 minute with the following processing
composition:
Water 100.00 cc. KOH 11.20 g. Hydroxyethyl cellulose (high
viscosity) ?Commercially available from Hercules Powder Co., under
the trade name of "Natrasol 250"! 3.90 g. Benzotriazole 3.50 g.
Sodium thiosulfate 0.50 g. N-benzyl-.alpha.-picolinium bromide 2.00
g. Zinc nitrate 0.50 g. Lithium nitrate 0.50 g.
to provide a negative image having a D.sub.max. of 0.50 and a
D.sub.min. of 0.02 for a .DELTA. of 0.48. Upon careful inspection
of the negative image, the bis-hydroquinonyl developer was observed
to be a good discriminating, low staining, black-and-white
developer.
EXAMPLE 6
A silver iodobromide emulsion was exposed and then developed by
spreading between the thus-exposed emulsion and a superposed
silver-receptive stratum at a gap of .0022 in. an aqueous
processing composition comprising:
Water 8289 cc. Hydroxyethyl cellulose 366 gm. Sodium sulfite 260
gm. Sodium thiosulfate (hypo) 741 gm. Potassium iodide 15 gm.
6-nitrobenzimidazole 10.8 gm. gm. Sodium hydroxide 425 gm.
After an imbibition period of ten seconds, the silver-receptive
stratum was separated to reveal a clear positive silver image.
The following examples illustrate the use of novel dye developers
of this invention in the preparation of color images.
EXAMPLE 7
A photosensitive element was prepared by coating a gelatin
subcoated film base at a speed of 10 feet/minute with a solution
comprising 0.33 gm. of
2-(omega-hydroquinonyl-pentyl)-1,4-dihydroxy-5,8-bis-.alpha.-methyl-propyl
amino-anthraquinone (prepared as in Example 4) and 16 drops of
dimethylformamide dissolved in 10.0 cc. of 2 percent cellulose
acetate hydrogen phthalate in methyl cellosolve. After this coating
dried, a red-sensitive silver iodobromide emulsion was coated on at
a speed of 5 feet/minute and allowed to dry. This photosensitive
element was exposed for 2 seconds and processed by spreading
between the thus-exposed photosensitive element and a superposed
image-receiving element, at a gap of 0.0026 inch, the aqueous
processing composition of Example 5. The image-receiving element
was prepared in accordance with the disclosure of the copending
application of Edwin H. Land, Ser. No. 234,864, filed Nov. 1, 1962,
and comprised a layer of a 2:1 mixture, by weight, of polyvinyl
alcohol and poly-4-vinylpyridine, a layer of polyvinyl alcohol, and
a layer of a half-butyl ester of poly-(ethylene/maleic anhydride)
coated on a baryta paper support. After an imbibition period of
approximately one minute, the image-receiving element was separated
and contained a cyan image.
EXAMPLE 8
A photosensitive element was prepared by coating a gelatin
subcoated film base at a speed of 10 feet/minute with a solution
comprising 0.18 gm. of
2-(omega-hydroquinonyl-pentyl)-1,4,5,8-tetrahydroxyanthraquinone
(as prepared in Example 2) and ten drops of dimethylformamide
dissolved in 5.0 cc. of a solution of 2 percent cellulose acetate
hydrogen phthalate in a 50/50 acetone-tetrahydrofuran mixture.
After this coating dried, a green-sensitive silver iodobromide
emulsion was coated on at a speed of 5 feet/minute and allowed to
dry. This photosensitive element was exposed for 2 seconds and
processed in the manner described in the preceding example to
provide a reddish transfer image.
The addition of 0.2 gm. of 4'-methylphenyl-hydroquinone to the
processing solution gave a comparable image having an appreciably
lower D.sub.min.
While, for purposes of illustrating the invention, the
bis-hydroquinonyl developing agent (Example 5) and the dye
developer (Examples 7-8) have been shown to be initially in a layer
in the photosensitive element, it will be appreciated that the
invention is not so limited and they may, for example, be present
initially in the processing composition.
As was mentioned heretofore, the bis-hydroquinonyl silver halide
developing agents of this invention are good discriminating
developers which give little or no stain, making them useful both
in black-and-white photography and as auxiliary or accelerating
developers in color photographic processes such as those employing
dye developers.
The dye developers of this invention are useful "single-ended"
anthraquinone dye developers, i.e., anthraquinone dyes containing a
single developing group linked to the dye nucleus. Particularly
useful are the cyan dye developers obtained where X of the formula
is a secondary amino group. The present invention thus provides an
effective method for providing single-ended developers,
particularly cyan dye developers, useful in preparing color
images.
The dye developers of this invention are also useful in integral
multilayer photosensitive elements for use in multicolor diffusion
transfer processes. As an example of such photosensitive elements,
mention may be made of the photosensitive elements disclosed and
claimed in the copending U.S. application of Edwin H. Land and
Howard G. Rogers, Ser. No. 565,135, filed Feb. 13, 1956, wherein at
least two selectively sensitized photosensitive strata are
superposed on a single support and are processed, simultaneously
and without separation, with a single common image-receiving
element. A suitable arrangement of this type comprises a support
carrying a red-sensitive silver halide emulsion stratum, a
green-sensitive silver halide emulsion stratum and a blue-sensitive
silver halide emulsion stratum, said emulsions having associated
therewith, respectively, a cyan dye developer, a magenta dye
developer and a yellow dye developer. In one of the preferred
embodiments of photosensitive elements of this type, the dye
developers are disposed in separate alkali-permeable layers behind
the photosensitive silver halide emulsion stratum with which they
are associated.
The photosensitive elements within the scope of this invention may
be used in film units which contain a plurality of photosensitive
frames. The photosensitive elements of this invention are
especially useful in composite roll film and film pack structures
intended for use in a "Polaroid Land Camera", sold by Polaroid
Corporation, Cambridge 39, Mass., or a similar camera structure
such, for example, as the roll film type camera forming the subject
matter of U.S. Pat. No. 2,435,717, issued to Edwin H. Land on Feb.
10, 1948, or the film pack type camera shown in U.S. Pat. No.
2,991,702, issued to Vaito K. Eloranta on July 11, 1961. In
general, such composite roll films comprise a photosensitive roll,
a roll of image-receiving material and a plurality of pods
containing an aqueous alkaline processing solution. The rolls and
pods are so associated with each other that, upon processing, the
photosensitive element may be superposed on the image-receiving
element and the pods may be ruptured to spread the aqueous alkaline
processing solution between the superposed elements. The nature and
construction of the pods used in such units are well known to the
art. See, for example, U.S. Pat. Nos. 2,543,181 and 2,634,886,
issued to Edwin H. Land.
It will be noted that the liquid processing composition may contain
one or more auxiliary or accelerating silver halide developing
agents, such as p-methylaminophenol (Metol); 2,4-diaminophenol
(Amidol); benzylaminophenol; hydroquinones; a substituted
hydroquinone such as toluhydroquinone, phenylhydroquinone, or
4'-methylphenylhydroquinone; or a 3-pyrazolidone such as
1-phenyl-3-pyrazolidone. These silver halide developing agents are
substantially colorless, at least in their unoxidized form. It is
possible that some of the dye developer oxidized in exposed areas
may be oxidized by an energy transfer reaction with oxidized
auxiliary developing agent.
In addition, development may be effected in the presence of an
onium compound, particularly a quaternary ammonium compound, in
accordance with the processes disclosed and claimed in the
copending application of Milton Green and Howard G. Rogers, Ser.
No. 50,851, filed Aug. 22, 1960.
The dye developers of this invention may be used also in
conventional photographic processes, such as tray or tank
development of conventional photosensitive films, plates or papers
to obtain black-and-white, monochromatic or toned prints or
negatives. By way of example, a developer composition suitable for
such use may comprise an aqueous solution of approximately 1-2
percent of the dye developer, 1 percent sodium hydroxide, 2 percent
sodium sulfite and 0.05 percent potassium bromide. After
development is completed, any unreacted dye developer is washed out
of the photosensitive element, preferably with an alkaline washing
medium or other medium in which the unreacted dye developer is
soluble. The expression "toned" is used to designate photographic
images wherein the silver is retained with the precipitated dye,
whereas "monochromatic" is intended to designate dye images free of
silver.
It should be noted that the dye developers of this medium are
self-sufficient to provide the desired color image and do not
depend upon coupling reactions to produce the desired color. They
thus provide a complete departure from conventional photographic
color processes in which the color is produced by a coupling
reaction between a "color former" or "coupler" and the oxidized
developing agent, as well as so-called auto-coupling processes in
which color is obtained by a reaction of the oxidized developing
agent with unoxidized developing agent.
It will be apparent that, by appropriate selection of the
image-receiving element from among suitable known opaque and
transparent materials, it is possible to obtain either a colored
positive reflection print or a colored positive transparency.
Likewise, the inventive concepts herein set forth are adaptable for
multicolor work by the use of special photographic materials, for
example, film materials of the type containing two or more
photosensitized elements associated with an appropriate number of
image-receiving elements and adapted to be treated with one or more
liquid processing compositions, appropriate dye developers suitable
to impart the desired subtractive colors being incorporated in the
photosensitized elements or in the liquid processing compositions.
Examples of such photographic materials are disclosed in U.S. Pat.
No. 2,647,049 to Edwin H. Land.
As examples of useful image-receiving materials, mention may be
made of nylon, e.g., N-methoxymethyl-polyhexamethylene adipamide,
polyvinyl alcohol, and gelatin, particularly polyvinyl alcohol or
gelatin containing a dye mordant such as poly-4-vinylpyridine. The
image-receiving element also may contain a development restrainer,
e.g., 1-phenyl-5-mercaptotetrazole, as disclosed in the copending
application of Howard G. Rogers and Harriet W. Lutes, Ser. No.
50,849, filed Aug. 22, 1960.
The dye developers herein set forth are also useful in the
formation of colored images in accordance with the photographic
products and processes described and claimed in U.S. Pat. No.
2,968,554, issued to Edwin H. Land on Jan. 17, 1961.
The novel dye developers herein disclosed are also suitable for use
as dyes for textile fibers, such as nylon.
In the preceding portions of the specification, the expression
"color" has been frequently used. This expression is intended to
include the use of a plurality of colors to obtain black.
Since certain changes may be made in the above products,
compositions and processes without departing from the scope of the
invention herein involved, it is intended that all matter contained
in the above description shall be interpreted as illustrative and
not in a limiting sense.
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