FIELD OF THE INVENTION
This invention relates to a photographic element and process
comprising a silver halide emulsion layer having associated therewith a certain
magenta benzotriazole-releasing DIR coupler.
BACKGROUND OF THE INVENTION
Many photographic materials, particularly color negative films,
contain so-called DIR (development inhibitor releasing) couplers. In addition to
forming imaging dye, DIR couplers release inhibitors that can restrain silver
development in the layer in which release occurs as well as in other layers of a
multilayer photographic material. DIR couplers can help control gamma or
contrast, can enhance sharpness or acutance, can reduce granularity and can
provide color correction via interlayer interimage effects. There has been a need
for more effective magenta dye-forming DIR couplers. Magenta DIR couplers
that provide high interimage color correction are particularly desirable for modem
color negative films. In addition, it is desirable that such couplers have high
activity to maximize rates and efficiencies of inhibitor release and to minimize
laydowns. It is also desirable that the magenta DIR couplers be stable toward long
term storage particularly at elevated temperatures. The DIR couplers of this
invention possess all of these desirable properties, particularly higher activity and
greater stability than analogous magenta-dye forming DIR couplers of the prior
art.
There are known pyrazolone couplers that contain an unsubstituted
benzotriazole coupling-off group, which is outside the scope of the R8 and R9
substituents of this invention. U.S. Patent No. 4,015,988 lists pyrazolone couplers
(9 & 10) with methyl or bromo substituents. However, both couplers have o-methoxy
substituents on the anilino group, which is outside the scope of the
anilino substituents of this invention. JP60 128,444 discloses a coupler with a
dimethyl-substituted benzotriazole, but this coupler also has an o-methoxy
substituent on the anilino group.
Many of the prior art couplers, such as those in GB 1,455,967, have
a p-nitro substituent on the 1-phenyl group that is outside the scope of the
substituents of this invention. U.S. Patent 4,477,563 deals generally with
couplers, such as pyrazolone couplers, having benzotriazole leaving groups, but
the exemplified couplers contain 2,4,6-trichloro substitution on the 1-phenyl ring
or otherwise contain substituents which do not provide the desired improvement in
reactivity.
A problem to be solved is to provide a photographic element
comprising a silver halide emeulsion layer having associated therewith a magenta
dye-forming coupler that has good reactivity and good raw stock keeping.
SUMMARY OF THE INVENTION
The invention provides a photographic element comprising a silver
halide emulsion layer having associated therewith a 1-phenyl-3-anilino-4-benzotriazolyl-5-pyrazolone
magenta dye-forming DIR coupler of structure I:
wherein:
R1 is hydrogen, chlorine, fluorine or a methyl group; R2, R3, and R4 are individually selected from the group consisting of
hydrogen, halogen, alkyl, phenyl, alkoxy, phenoxy, alkylthio, carbonamido,
sulfonamido, carbamoyl, alkoxycarbonyl and aryloxycarbonyl groups; R5 is hydrogen, bromine, chlorine, fluorine, or an alkyl group; R6 and R7 are independently selected from the group consisting of
hydrogen, halogen, carbonamido, carbamoyl, sulfonamido, sulfamoyl,
alkylsulfonyl, arylsulfonyl, alkylsulfoxyl, arylsulfoxyl, sulfonyloxy,
alkoxycarbonyl, aryloxycarbonyl, acyloxy, acyl, imido, trifluoromethyl and cyano
groups, provided that at least one of R6 and R7 is not hydrogen; R8 and R9 are independently selected from the group consisting of
hydrogen, halogen, alkyl, phenyl, alkoxy, phenoxy, alkoxycarbonyl,
aryloxycarbonyl, carbonamido, sulfonamido, carbamoyl and carbamoyloxy
groups, provided that at least one of R8 and R9 is not hydrogen; further provided that (1) when R5 is hydrogen, the sum of the Hammett's
sigma values of R6 and R7, referenced to the position of the anilino nitrogen, is at
least 0.30, and R1 is also hydrogen, and (2) when R5 is bromine, chlorine, fluorine,
or an alkyl group, the sum of the Hammett sigma values of R6 and R7, referenced
to the position of the anilino nitrogen, is a least 0.20; and the sum of pi values of R8 and R9 taken together is at least 0.60 but not
more than 3.00.
The invention also provides a magenta DIR coupler, a silver halide
emulsion containing the coupler, the dye formed by the combination of the coupler
with a color developer, an image containing the foregoing dye, and a process of
forming an image comprising contacting the element of the invention with a color
developer after the element has been imagewise exposed to light.
The element of the invention provides a magenta dye-forming
coupler that has good reactivity and good raw stock keeping.
DETAILED DESCRIPTION OF THE INVENTION
The photographic materials of this invention comprising certain
magenta dye-forming pyrazolone DIR couplers are described in the foregoing
Summary of the Invention.
It is important to note that the coupler of the invention bears a
hydrogen in the 6-position of the N-phenyl ring. This is essential for reactivity as
evidenced by the results using C1, C2, and C3 in the photographic examples.
R1 is hydrogen, chlorine, fluorine or a methyl group. For greater
coupler reactivity, embodiments wherein R1 is hydrogen are particularly useful.
Embodiments wherein R1, R2, and R4 are hydrogen and R3 is hydrogen or methyl
are also particularly useful.
R2, R3 and R4 may suitably be individually selected from hydrogen,
halogen, alkyl, phenyl, alkoxy, phenoxy, alkylthio, carbonamido, sulfonamido,
carbamoyl, alkoxycarbonyl or aryloxycarbonyl groups. Hydrogen, fluoro, chloro,
alkyl, alkoxy, carbonamido, and alkoxycarbonyl groups are most typical.
R5 is hydrogen, bromine, chlorine, fluorine or an alkyl group.
Embodiments where R5 is chlorine, fluorine, or methyl are suitable examples
while chlorine is conveniently employed.
R6 and R7 are independently selected from the group consisting of
halogen, carbonamido, carbamoyl, sulfonamido, sulfamoyl, alkylsulfonyl,
arylsulfonyl, alkylsulfoxyl, arylsulfoxyl, sulfonyloxy, alkoxycarbonyl,
aryloxycarbonyl, acyloxy, acyl, imido, trifluoromethyl and cyano groups.
Alkylsulfonyl, alkoxycarbonyl, carbonamido and cyano groups are generally
useful, with usually only one of the 4- or 5-position relative to the anilino nitrogen
being occupied by a nonhydrogen substituent. At least one of R6 and R7 is a
nonhydrogen substituent.
When R5 is hydrogen, the sum of the Hammett sigma values of R6
and R7, referenced to the position of the anilino nitrogen, is at least 0.30, and R1 is
also hydrogen. When R5 is chlorine or fluorine, the sum of the Hammett sigma
values of R6 and R7, referenced to the position of the anilino nitrogen, is a least
0.20.
R8 and R9 are individually selected from the group consisting of
hydrogen, halogen, alkyl, phenyl, alkoxy, phenoxy, alkoxycarbonyl,
aryloxycarbonyl, carbonamido (including but not limited to alkyl-, aryl-, alkoxy-and
aryloxycarbonamido), sulfonamido, carbamoyl and carbamoyloxy groups.
Phenoxycarbonyl and derivatives are suitably used such as p-chlorophenoxycarbonyl,
p-methylphenoxycarbonyl or p-methylthiophenoxycarbonyl,
as well as alkoxy, carbonamido, and alkoxycarbonyl
substituents. Other examples are butoxycarbonylmethoxycarbonyl, 1-methyl-1-butoxycarbonylmethoxycarbonyl,
n-pentylcarbonylamino, 5,6-dichloro, 5,6-dipropoxy,
and n-butyl. It is necessary that at least one of R8 and R9 is not
hydrogen.
The sum of pi values of R8 and R9 taken together is at least 0.60 but
not more than 3.00.
Stability may be improved when R
5 is chlorine or fluorine and the
sum of the Hammett sigma values of R
6 and R
7 taken together is at least 0.25. In
one embodiment, the sum of the pi values of R
8 and R
9 is from 1.0 to 2.2, which
tends to provide efficient development inhibition and good interlayer interimage.
In another embodiment, at least one of R
8 and R
9 is a readily hydrolyzable group,
such as a phenoxycarbonyl group or a -CO
2CH
2CO
2R
10 group, where R
10 is an
alkyl or phenyl group, to prevent seasoning of developer solutions with strong
inhibitors. By
readily hydrolyzable group
it is meant that the half life for
hydrolysis at 40°C in a Kodak C-41 developer of the compound to which the
group is attached is not more than one hour. To minimize coupler wandering it is
also desirable that the total number of carbon atoms plus halogen atoms in R
1-R
7
taken together be at least 8, and preferably at least 10.
The use of Hammett sigma values and pi values to describe
chemical properties is well established in the literature and is discussed, for
example, in "Exploring QSAR, Fundamentals and Applications in Chemistry and
Biology", C. Hansch and A. Leo, American Chemical Society, Washington, D.C.
1995. There are numerous published sources for Hammett
s sigma and for pi
values including: "Exploring QSAR, Hydrophobic, Electronic and Steric
Constants", C. Hansch, A. Leo and D. Hoekman, American Chemical Society,
Washington, D.C., 1995; "The Chemists Companion", A.J. Gorden and R.A. Ford,
John Wiley & Sons, New York, 1972; "Substituent Constants for Correlation
Analysis", C. Hansch and A. Leo, John Wiley & Sons, New York, 1979; and A.
Leo in "Comprehensive Medicinal Chemistry", edited by C. Hansch, P.G.
Sammes, and J.B. Taylor, Permagon Press, New York, 1972. Generally, pi values
of substituents increase with increasing hydrophobicity and sigma values increase
with increasing electron-withdrawing power of the substituent in the vicinity of
the point of attachment. Pi and sigma values for hydrogen equal zero.
Useful coated levels of the magenta dye-forming pyrazolone DIR
couplers of this invention range from about 0.005 to about 0.40 g/sq m, or more
typically from 0.01 to 0.20 g/sq m.
The couplers of this invention are usually utilized by dissolving
them in high-boiling coupler solvents and then dispersing the organic coupler plus
coupler solvent mixtures as small particles in aqueous solutions of gelatin and
surfactant (via milling or homogenization). Removable auxiliary organic solvents
such as ethyl acetate or cyclohexanone may also be used in the preparation of such
dispersions to facilitate the dissolution of the coupler in the organic phase.
Coupler solvents useful for the practice of this invention include, but are not
limited to aryl phosphates (e.g. tritolyl phosphate), alkyl phosphates (e.g. trioctyl
phosphate), mixed aryl alkyl phosphates (e.g. diphenyl 2-ethylhexyl phosphate),
aryl, alkyl or mixed aryl alkyl phosphonates, phosphine oxides (e.g.
trioctylphosphine oxide), esters of aromatic acids (e.g. dibutyl phthalate, octyl
benzoate, or benzyl salicylate) esters of aliphatic acids (e.g. acetyl tributyl citrate
or dibutyl sebecate), alcohols (e.g. 2-hexyl-1-decanol), phenols (e.g. p-dodecylphenol),
carbonamides (e.g. N,N-dibutyldodecanamide or N-butylacetanalide),
sulfoxides (e.g. bis(2-ethylhexyl)sulfoxide), sulfonamides (e.g.
N,N-dibutyl-p-toluenesulfonamide) or hydrocarbons (e.g. dodecylbenzene).
Additional coupler solvents and auxiliary solvents are noted in Research
Disclosure, December 1989, Item 308,119, p 993. Useful coupler: coupler
solvent weight ratios range from about 1:0.1 to 1:8.0, with 1:0.2 to 1:4.0 being
preferred.
The pyrazolone DIR couplers of this invention may be used
together with a variety of other types of couplers in the same layer or in different
layers of a multilayer photographic material. Specifically contemplated is the use
of pyrazolone DIR couplers of this invention in green-sensitive photographic
elements together with one or more 1-phenyl-3-anilino-5-pyrazolone magenta dye-forming
imaging couplers as defined by structures I, III and IV in U.S. Patent
5,200,309 of Merkel and Singer. Such a dye-forming imaging coupler has the
formula:
wherein:
Ar is selected from the group consisting of unsubstituted aryl groups,
substituted aryl groups and substituted pyridyl groups, the substituents being
selected from the group consisting of halogen atoms and cyano, alkylsulfonyl,
arylsulfonyl, sulfamoyl, sulfonamido, carbamoyl, carbonamido, alkoxy, acyloxy,
aryloxy, alkoxycarbonyl, aryloxycarbonyl, ureido, nitro, alkyl and trifluoromethyl
groups; Y is selected from the group consisting of anilino, acylamino and ureido
groups and one of said groups substituted with one or more substituents selected
from the group consisting of halogen atoms, and alkyl, aryl, alkoxy, aryloxy,
carbonamido, carbamoyl, sulfonamido, sulfamoyl, alkylsulfoxyl, arylsulfoxyl,
alkylsulfonyl, arylsulfonyl, alkoxycarbonyl, aryloxycarbonyl, acyl, acyloxy,
ureido, imido, carbamate, heterocyclic, cyano, trifluoromethyl, alkylthio, nitro,
carboxyl and hydroxyl groups, and groups which form a link to a polymeric chain,
and wherein Y contains at least 6 carbon atoms; and X is a coupling-off group selected from the group consisting of halogen
atoms, and alkoxy, aryloxy, alkylthio, arylthio, acyloxy, sulfonamido, sulfonyloxy,
carbonamido, arylazo, nitrogen-containing heterocyclic and imido groups.
Suitably, Y has the formula:
wherein
- p is from zero to 2 and each RB is in a meta or para position with respect to
RA;
- each RB is individually selected from the group consisting of halogen atoms
and alkyl, alkoxy, aryloxy, carbonamido, carbamoyl, sulfonamido, sulfamoyl,
alkylsulfoxyl, arylsulfoxyl, alkylsulfonyl, arylsulfonyl, alkoxycarbonyl,
aryloxycarbonyl, acyloxy, ureido, imido, carbamate, heterocyclic, cyano, nitro,
acyl, trifluoromethyl, alkylthio and carboxyl groups; and
- RA is selected from the group consisting of
hydrogen, halogen atoms and alkyl, alkoxy, aryloxy, alkylthio, carbonamido,
carbamoyl, sulfonamido, sulfamoyl, alkylsulfonyl, arylsulfonyl, alkoxycarbonyl,
acyloxy, acyl, cyano, nitro and trifluoromethyl groups.
One useful X has the formula:
wherein R
C and R
D are individually selected from the group consisting of
hydrogen, halogen atoms and alkyl, alkoxy, aryloxy, carbonamido, ureido,
carbamate, sulfonamido, carbamoyl, sulfamoyl, acyloxy, alkoxycarbonyl,
aryloxycarbonyl, amino and carboxyl groups; and wherein q is 0, 1 or 2 and R
D
may be in the meta or para position with respect to the sulfur atom.
Particularly contemplated is the use of the pyrazolone DIR couplers of this
invention in combination with M-1 and M-2 (see Example 1). Examples of
pyrazolone DIR couplers of this invention include, but are not limited to A1-A29,
below:
Unless otherwise specifically stated, substituent groups which may
be substituted on molecules herein include any groups, whether substituted or
unsubstituted, which do not destroy properties necessary for photographic utility.
When the term "group" is applied to the identification of a substituent containing a
substitutable hydrogen, it is intended to encompass not only the substituent's
unsubstituted form, but also its form further substituted with any group or groups
as herein mentioned. Suitably, the group may be halogen or may be bonded to the
remainder of the molecule by an atom of carbon, silicon, oxygen, nitrogen,
phosphorous, or sulfur. The substituent may be, for example, halogen, such as
chlorine, bromine or fluorine; nitro; hydroxyl; cyano; carboxyl; or groups which
may be further substituted, such as alkyl, including straight or branched chain or
cyclic alkyl, such as methyl, trifluoromethyl, ethyl, t-butyl, 3-(2,4-di-t-pentylphenoxy)
propyl, and tetradecyl; alkenyl, such as ethylene, 2-butene; alkoxy,
such as methoxy, ethoxy, propoxy, butoxy, 2-methoxyethoxy, sec-butoxy,
hexyloxy, 2-ethylhexyloxy, tetradecyloxy, 2-(2,4-di-t-pentylphenoxy)ethoxy, and
2-dodecyloxyethoxy; aryl such as phenyl, 4-t-butylphenyl, 2,4,6-trimethylphenyl,
naphthyl; aryloxy, such as phenoxy, 2-methylphenoxy, alpha- or beta-naphthyloxy,
and 4-tolyloxy; carbonamido, such as acetamido, benzamido, butyramido,
tetradecanamido, alpha-(2,4-di-t-pentyl-phenoxy)acetamido, alpha-(2,4-di-t-pentylphenoxy)butyramido,
alpha-(3-pentadecylphenoxy)-hexanamido, alpha-(4-hydroxy-3-t-butylphenoxy)-tetradecanamido,
2-oxo-pyrrolidin-1-yl,2-oxo-5-tetradecylpyrrolin-1-yl,
N-methyltetradecanamido, N-succinimido, N-phthalimido,
2,5-dioxo-1-oxazolidinyl, 3-dodecyl-2,5-dioxo-1-imidazolyl, and N-acetyl-N-dodecylamino,
ethoxycarbonylamino, phenoxycarbonylamino,
benzyloxycarbonylamino, hexadecyloxycarbonylamino, 2,4-di-t-butylphenoxycarbonylamino,
phenylcarbonylamino, 2,5-(di-t-pentylphenyl)carbonylamino,
p-dodecyl-phenylcarbonylamino, p-tolylcarbonylamino,
N-methylureido, N,N-dimethylureido, N-methyl-N-dodecylureido,
N-hexadecylureido, N,N-dioctadecylureido, N,N-dioctyl-N'-ethylureido,
N-phenylureido, N,N-diphenylureido, N-phenyl-N-p-tolylureido, N-(m-hexadecylphenyl)ureido,
N,N-(2,5-di-t-pentylphenyl)-N'-ethylureido, and t-butylcarbonamido;
sulfonamido, such as methylsulfonamido,
benzenesulfonamido, p-tolylsulfonamido, p-dodecylbenzenesulfonamido, N-methyltetradecylsulfonamido,
N,N-dipropyl-sulfamoylamino, and
hexadecylsulfonamido; sulfamoyl, such as N-methylsulfamoyl, N-ethylsulfamoyl,
N,N-dipropylsulfamoyl, N-hexadecylsulfamoyl, N,N-dimethylsulfamoyl; N-[3-(dodecyloxy)propyl]sulfamoyl,
N-[4-(2,4-di-t-pentylphenoxy)butyl]sulfamoyl, N-methyl-N-tetradecylsulfamoyl,
and N-dodecylsulfamoyl; carbamoyl, such as N-methylcarbamoyl,
N,N-dibutylcarbamoyl, N-octadecylcarbamoyl, N-[4-(2,4-di-t-pentylphenoxy)butyl]carbamoyl,
N-methyl-N-tetradecylcarbamoyl, and N,N-dioctylcarbamoyl;
acyl, such as acetyl, (2,4-di-t-amylphenoxy)acetyl,
phenoxycarbonyl, p-dodecyloxyphenoxycarbonyl methoxycarbonyl,
butoxycarbonyl, tetradecyloxycarbonyl, ethoxycarbonyl, benzyloxycarbonyl, 3-pentadecyloxycarbonyl,
and dodecyloxycarbonyl; sulfonyl, such as
methoxysulfonyl, octyloxysulfonyl, tetradecyloxysulfonyl, 2-ethylhexyloxysulfonyl,
phenoxysulfonyl, 2,4-di-t-pentylphenoxysulfonyl,
methylsulfonyl, octylsulfonyl, 2-ethylhexylsulfonyl, dodecylsulfonyl,
hexadecylsulfonyl, phenylsulfonyl, 4-nonylphenylsulfonyl, and p-tolylsulfonyl;
sulfonyloxy, such as dodecylsulfonyloxy, and hexadecylsulfonyloxy; sulfinyl, such
as methylsulfinyl, octylsulfinyl, 2-ethylhexylsulfinyl, dodecylsulfinyl,
hexadecylsulfinyl, phenylsulflnyl, 4-nonylphenylsulfinyl, and p-tolylsulfinyl; thio,
such as ethylthio, octylthio, benzylthio, tetradecylthio, 2-(2,4-di-t-pentylphenoxy)ethylthio,
phenylthio, 2-butoxy-5-t-octylphenylthio, and p-tolylthio;
acyloxy, such as acetyloxy, benzoyloxy, octadecanoyloxy, p-dodecylamidobenzoyloxy,
N-phenylcarbamoyloxy, N-ethylcarbamoyloxy, and
cyclohexylcarbonyloxy; amine, such as phenylanilino, 2-chloroanilino,
diethylamine, dodecylamine; imino, such as 1-(N-phenylimido)ethyl, N-succinimido
or 3-benzylhydantoinyl; phosphate, such as dimethylphosphate and
ethylbutylphosphate; phosphite, such as diethyl and dihexylphosphite; a
heterocyclic group, a heterocyclic oxy group or a heterocyclic thio group, each of
which may be substituted and which contain a 3 to 7 membered heterocyclic ring
composed of carbon atoms and at least one hetero atom selected from the group
consisting of oxygen, nitrogen and sulfur, such as 2-furyl, 2-thienyl, 2-benzimidazolyloxy
or 2-benzothiazolyl; quaternary ammonium, such as
triethylammonium; and silyloxy, such as trimethylsilyloxy.
If desired, the substituents may themselves be further substituted
one or more times with the described substituent groups. The particular
substituents used may be selected by those skilled in the art to attain the desired
photographic properties for a specific application and can include, for example,
hydrophobic groups, solubilizing groups, blocking groups, releasing or releasable
groups, etc. Generally, the above groups and substituents thereof may include
those having up to 48 carbon atoms, typically 1 to 36 carbon atoms and usually
less than 24 carbon atoms, but greater numbers are possible depending on the
particular substituents selected.
The materials of the invention can be used in any of the ways and
in any of the combinations known in the art. Typically, the invention materials are
incorporated in a silver halide emulsion and the emulsion coated as a layer on a
support to form part of a photographic element. Alternatively, unless provided
otherwise, they can be incorporated at a location adjacent to the silver halide
emulsion layer where, during development, they will be in reactive association
with development products such as oxidized color developing agent. Thus, as
used herein, the term "associated" signifies that the compound is in the silver
halide emulsion layer or in an adjacent location where, during processing, it is
capable of reacting with silver halide development products.
To control the migration of various components, it may be
desirable to include a high molecular weight hydrophobe or "ballast" group in
coupler molecules. Representative ballast groups include substituted or
unsubstituted alkyl or aryl groups containing 8 to 48 carbon atoms.
Representative substituents on such groups include alkyl, aryl, alkoxy, aryloxy,
alkylthio, hydroxy, halogen, alkoxycarbonyl, aryloxcarbonyl, carboxy, acyl,
acyloxy, amino, anilino, carbonamido, carbamoyl, alkylsulfonyl, arylsulfonyl,
sulfonamido, and sulfamoyl groups wherein the substituents typically contain 1 to
42 carbon atoms. Such substituents can also be further substituted.
The photographic elements can be single color elements or
multicolor elements. Multicolor elements contain image dye-forming units
sensitive to each of the three primary regions of the spectrum. Each unit can
comprise a single emulsion layer or multiple emulsion layers sensitive to a given
region of the spectrum. The layers of the element, including the layers of the
image-forming units, can be arranged in various orders as known in the art. In an
alternative format, the emulsions sensitive to each of the three primary regions of
the spectrum can be disposed as a single segmented layer.
A typical multicolor photographic element comprises a support
bearing a cyan dye image-forming unit comprised of at least one red-sensitive
silver halide emulsion layer having associated therewith at least one cyan dye-forming
coupler, a magenta dye image-forming unit comprising at least one green-sensitive
silver halide emulsion layer having associated therewith at least one
magenta dye-forming coupler, and a yellow dye image-forming unit comprising at
least one blue-sensitive silver halide emulsion layer having associated therewith at
least one yellow dye-forming coupler. The element can contain additional layers,
such as filter layers, interlayers, overcoat layers, subbing layers, and the like.
If desired, the photographic element can be used in conjunction
with an applied magnetic layer as described in Research Disclosure, November
1992, Item 34390 published by Kenneth Mason Publications, Ltd., Dudley Annex,
12a North Street, Emsworth, Hampshire P010 7DQ, ENGLAND, and as described
in Hatsumi Kyoukai Koukai Gihou No. 94-6023, published March 15,1994,
avaliable from the Japanese Patent Office, the contents of which are incorporated
herein by reference. When it is desired to employ the inventive materials in a
small format film, Research Disclosure, June 1994, Item 36230, provides suitable
embodiments.
In the following discussion of suitable materials for use in the
emulsions and elements of this invention, reference will be made to Research
Disclosure, September 1996, Item 38957, available as described above, which is
referred to herein by the term "Research Disclosure". The contents of the
Research Disclosure, including the patents and publications referenced therein, are
incorporated herein by reference, and the Sections hereafter referred to are
Sections of the Research Disclosure.
Except as provided, the silver halide emulsion containing elements
employed in this invention can be either negative-working or positive-working as
indicated by the type of processing instructions (i.e. color negative, reversal, or
direct positive processing) provided with the element. Suitable emulsions and
their preparation as well as methods of chemical and spectral sensitization are
described in Sections I through V. Various additives such as UV dyes,
brighteners, antifoggants, stabilizers, light absorbing and scattering materials, and
physical property modifying addenda such as hardeners, coating aids, plasticizers,
lubricants and matting agents are described, for example, in Sections II and VI
through VIII. Color materials are described in Sections X through XIII. Suitable
methods for incorporating couplers and dyes, including dipersions in organic
solvents, are described in Section X(E). Scan facilitating is described in Section
XIV. Supports, exposure, development systems, and processing methods and
agents are described in Sections XV to XX. The information contained in the
September 1994 Research Disclosure, Item No. 36544 referenced above, is
updated in the September 1996 Research Disclosure, Item No. 38957. Certain
desirable photographic elements and processing steps, including those useful in
conjunction with color reflective prints, are described in Research Disclosure,
Item 37038, February 1995.
Coupling-off groups are well known in the art. Such groups can
determine the chemical equivalency of a coupler, i.e., whether it is a 2-equivalent
or a 4-equivalent coupler, or modify the reactivity of the coupler. Such groups can
advantageously affect the layer in which the coupler is coated, or other layers in
the photographic recording material, by performing, after release from the coupler,
functions such as dye formation, dye hue adjustment, development acceleration or
inhibition, bleach acceleration or inhibition, electron transfer facilitation, color
correction and the like.
The presence of hydrogen at the coupling site provides a 4-equivalent
coupler, and the presence of another coupling-off group usually
provides a 2-equivalent coupler. Representative classes of such coupling-off
groups include, for example, chloro, alkoxy, aryloxy, hetero-oxy, sulfonyloxy,
acyloxy, acyl, heterocyclyl, sulfonamido, mercaptotetrazole, benzothiazole,
mercaptopropionic acid, phosphonyloxy, arylthio, and arylazo. These coupling-off
groups are described in the art, for example, in U.S. Pat. Nos. 2,455,169,
3,227,551, 3,432,521, 3,476,563, 3,617,291, 3,880,661, 4,052,212 and 4,134,766;
and in UK. Patents and published application Nos. 1,466,728,1,531,927,
1,533,039, 2,006,755A and 2,017,704A, the disclosures of which are incorporated
herein by reference.
Image dye-forming couplers may be included in the element such
as couplers that form cyan dyes upon reaction with oxidized color developing
agents which are described in such representative patents and publications as: U.S.
Pat. Nos. 2,367,531, 2,423,730, 2,474,293, 2,772,162, 2,895,826, 3,002,836,
3,034,892, 3,041,236, 4,333,999, 4,883,746 and "Farbkuppler-eine Literature
Ubersicht," published in Agfa Mitteilungen, Band III, pp. 156-175 (1961).
Preferably such couplers are phenols and naphthols that form cyan dyes on
reaction with oxidized color developing agent.
Couplers that form magenta dyes upon reaction with oxidized color
developing agent are described in such representative patents and publications as:
U.S. Pat. Nos. 2,311,082, 2,343,703, 2,369,489, 2,600,788, 2,908,573, 3,062,653,
3,152,896, 3,519,429, 3,758,309, 4,540,654, and "Farbkuppler-eine Literature
Ubersicht," published in Agfa Mitteilungen, Band III, pp. 126-156 (1961).
Preferably such couplers are pyrazolones, pyrazolotriazoles, or
pyrazolobenzimidazoles that form magenta dyes upon reaction with oxidized color
developing agents.
Couplers that form yellow dyes upon reaction with oxidized color
developing agent are described in such representative patents and publications as:
U.S. Pat. Nos. 2,298,443, 2,407,210, 2,875,057, 3,048,194, 3,265,506, 3,447,928,
4,022,620, 4,443,536, and "Farbkuppler-eine Literature Ubersicht," published in
Agfa Mitteilungen, Band III, pp. 112-126 (1961). Such couplers are typically
open chain ketomethylene compounds.
Couplers that form colorless products upon reaction with oxidized
color developing agent are described in such representative patents as: UK. Patent
No. 861,138; U.S. Pat. Nos. 3,632,345, 3,928,041, 3,958,993 and 3,961,959.
Typically such couplers are cyclic carbonyl containing compounds that form
colorless products on reaction with an oxidized color developing agent.
Couplers that form black dyes upon reaction with oxidized color
developing agent are described in such representative patents as U.S. Patent Nos.
1,939,231; 2,181,944; 2,333,106; and 4,126,461; German OLS No. 2,644,194 and
German OLS No. 2,650,764. Typically, such couplers are resorcinols or m-aminophenols
that form black or neutral products on reaction with oxidized color
developing agent.
In addition to the foregoing, so-called "universal" or "washout"
couplers may be employed. These couplers do not contribute to image dye-formation.
Thus, for example, a naphthol having an unsubstituted carbamoyl or
one substituted with a low molecular weight substituent at the 2- or 3- position
may be employed. Couplers of this type are described, for example, in U.S. Patent
Nos. 5,026,628, 5,151,343, and 5,234,800.
It may be useful to use a combination of couplers any of which may
contain known ballasts or coupling-off groups such as those described in U.S.
Patent 4,301,235; U.S. Patent 4,853,319 and U.S. Patent 4,351,897. The coupler
may contain solubilizing groups such as described in U.S. Patent 4,482,629. The
coupler may also be used in association with "wrong" colored couplers (e.g. to
adjust levels of interlayer correction) and, in color negative applications, with
masking couplers such as those described in EP 213.490; Japanese Published
Application 58-172,647; U.S. Patent Nos. 2,983,608; 4,070,191; and 4,273,861;
German Applications DE 2,706,117 and DE 2,643,965; UK. Patent 1,530,272; and
Japanese Application 58-113935. The masking couplers may be shifted or
blocked, if desired.
The invention materials may be used in association with materials
that release Photographically Useful Groups (PUGS) that accelerate or otherwise
modify the processing steps e.g. of bleaching or fixing to improve the quality of
the image. Bleach accelerator releasing couplers such as those described in EP
193,389; EP 301,477; U.S.4,163,669; U.S.4,865,956; and U.S.4,923,784, may
be useful. Also contemplated is use of the compositions in association with
nucleating agents, development accelerators or their precursors (UK Patent
2,097,140; UK. Patent 2,131,188); electron transfer agents (U.S. 4,859,578; U.S.
4,912,025); antifogging and anti color-mixing agents such as derivatives of
hydroquinones, aminophenols, amines, gallic acid; catechol; ascorbic acid;
hydrazides; sulfonamidophenols; and non color-forming couplers.
The invention materials may also be used in combination with filter
dye layers comprising colloidal silver sol or yellow, cyan, and/or magenta filter
dyes, either as oil-in-water dispersions, latex dispersions or as solid particle
dispersions. Additionally, they may be used with "smearing" couplers (e.g. as
described in U.S. 4,366,237; EP 96,570; U.S. 4,420,556; and U.S. 4,543,323.)
Also, the compositions may be blocked or coated in protected form as described,
for example, in Japanese Application 61/258,249 or U.S. 5,019,492.
The invention materials may further be used in combination with
image-modifying compounds that release PUGS such as "Developer Inhibitor-Releasing"
compounds (DIR's). DIR's useful in conjunction with the
compositions of the invention are known in the art and examples are described in
U.S. Patent Nos. 3,137,578; 3,148,022; 3,148,062; 3,227,554; 3,384,657;
3,379,529; 3,615,506; 3,617,291; 3,620,746; 3,701,783; 3,733,201; 4,049,455;
4,095,984; 4,126,459; 4,149,886; 4,150,228; 4,211,562; 4,248,962; 4,259,437;
4,362,878; 4,409,323; 4,477,563; 4,782,012; 4,962,018; 4,500,634; 4,579,816;
4,607,004; 4,618,571; 4,678,739; 4,746,600; 4,746,601; 4,791,049; 4,857,447;
4,865,959; 4,880,342; 4,886,736; 4,937,179; 4,946,767; 4,948,716; 4,952,485;
4,956,269; 4,959,299; 4,966,835; 4,985,336 as well as in patent publications GB
1,560,240; GB 2,007,662; GB 2,032,914; GB 2,099,167; DE 2,842,063, DE
2,937,127; DE 3,636,824; DE 3,644,416 as well as the following European Patent
Publications: 272,573; 335,319; 336,411; 346, 899; 362, 870; 365,252; 365,346;
373,382; 376,212; 377,463; 378,236; 384,670; 396,486; 401,612; 401,613.
Such compounds are also disclosed in "Developer-Inhibitor-Releasing
(DIR) Couplers for Color Photography," C.R. Barr, J.R. Thirtle and
P.W. Vittum in
Photographic Science and Engineering, Vol. 13, p. 174(1969),
incorporated herein by reference. Generally, the developer inhibitor-releasing
(DIR) couplers include a coupler moiety and an inhibitor coupling-off moiety (IN).
The inhibitor-releasing couplers may be of the time-delayed type (DIAR couplers)
which also include a timing moiety or chemical switch which produces a delayed
release of inhibitor. Examples of typical inhibitor moieties are: oxazoles,
thiazoles, diazoles, triazoles, oxadiazoles, thiadiazoles, oxathiazoles, thiatriazoles,
benzotriazoles, tetrazoles, benzimidazoles, indazoles, isoindazoles,
mercaptotetrazoles, selenotetrazoles, mercaptobenzothiazoles,
selenobenzothiazoles, mercaptobenzoxazoles, selenobenzoxazoles,
mercaptobenzimidazoles, selenobenzimidazoles, benzodiazoles,
mercaptooxazoles, mercaptothiadiazoles, mercaptothiazoles, mercaptotriazoles,
mercaptooxadiazoles, mercaptodiazoles, mercaptooxathiazoles, telleurotetrazoles
or benzisodiazoles. In a preferred embodiment, the inhibitor moiety or group is
selected from the following formulas:
wherein R
I is selected from the group consisting of straight and branched alkyls of
from 1 to about 8 carbon atoms, benzyl, phenyl, and alkoxy groups and such
groups containing none, one or more than one such substituent; R
II is selected
from R
I and -SR
I; R
III is a straight or branched alkyl group of from 1 to about 5
carbon atoms and m is from 1 to 3; and R
IV is selected from the group consisting
of hydrogen, halogens and alkoxy, phenyl and carbonamido groups, -COOR
V and
-NHCOOR
V wherein R
V is selected from substituted and unsubstituted alkyl and
aryl groups.
Although it is typical that the coupler moiety included in the
developer inhibitor-releasing coupler forms an image dye corresponding to the
layer in which it is located, it may also form a different color as one associated
with a different film layer. It may also be useful that the coupler moiety included
in the developer inhibitor-releasing coupler forms colorless products and/or
products that wash out of the photographic material during processing (so-called
"universal" couplers).
A compound such as a coupler may release a PUG directly upon
reaction of the compound during processing, or indirectly through a timing or
linking group. A timing group produces the time-delayed release of the PUG such
groups using an intramolecular nucleophilic substitution reaction (U.S.
4,248,962); groups utilizing an electron transfer reaction along a conjugated
system (U.S. 4,409,323; 4,421,845; 4,861,701, Japanese Applications 57-188035;
58-98728; 58-209736; 58-209738); groups that function as a coupler or reducing
agent after the coupler reaction (U.S. 4,438,193; U.S. 4,618,571) and groups that
combine the features describe above. It is typical that the timing group is of one
of the formulas:
wherein IN is the inhibitor moiety, Z is selected from the group consisting of nitro,
cyano, alkylsulfonyl; sulfamoyl (-SO
2NR
2); and sulfonamido (-NRSO
2R) groups;
n is 0 or 1; and R
VI is selected from the group consisting of substituted and
unsubstituted alkyl and phenyl groups. The oxygen atom of each timing group is
bonded to the coupling-off position of the respective coupler moiety of the DIAR.
The timing or linking groups may also function by electron transfer
down an unconjugated chain. Linking groups are known in the art under various
names. Often they have been referred to as groups capable of utilizing a
hemiacetal or iminoketal cleavage reaction or as groups capable of utilizing a
cleavage reaction due to ester hydrolysis such as U.S. 4,546,073. This electron
transfer down an unconjugated chain typically results in a relatively fast
decomposition and the production of carbon dioxide, formaldehyde, or other low
molecular weight by-products. The groups are exemplified in EP 464,612, EP
523,451, U.S. 4,146,396, Japanese Kokai 60-249148 and 60-249149.
Suitable developer inhibitor-releasing couplers for use in the
present invention include, but are not limited to, the following:
It is also contemplated that the concepts of the present invention
may be employed to obtain reflection color prints as described in Research
Disclosure, November 1979, Item 18716, available from Kenneth Mason
Publications, Ltd, Dudley Annex, 12a North Street, Emsworth, Hampshire P0101
7DQ, England, incorporated herein by reference. Materials of the invention may
be coated on pH adjusted support as described in U.S.4,917,994; on a support
with reduced oxygen permeability (EP 553,339); with epoxy solvents (EP
164,961); with nickel complex stabilizers (U.S. 4,346,165; U.S. 4,540,653 and
U.S. 4,906,559 for example); with ballasted chelating agents such as those in U.S.
4,994,359 to reduce sensitivity to polyvalent cations such as calcium; and with
stain reducing compounds such as described in U.S. 5,068,171. Other compounds
useful in combination with the invention are disclosed in Japanese Published
Applications described in Derwent Abstracts having accession numbers as
follows: 90-072,629, 90-072,630; 90-072,631; 90-072,632; 90-072,633; 90-072,634;
90-077,822; 90-078,229; 90-078,230; 90-079,336; 90-079,337; 90-079,338;
90-079,690; 90-079,691; 90-080,487; 90-080,488; 90-080,489; 90-080,490;
90-080,491; 90-080,492; 90-080,494; 90-085,928; 90-086,669; 90-086,670;
90-087,360; 90-087,361; 90-087,362; 90-087,363; 90-087,364; 90-088,097;
90-093,662; 90-093,663; 90-093,664; 90-093,665; 90-093,666; 90-093,668;
90-094,055; 90-094,056; 90-103,409; 83-62,586; 83-09,959.
Especially useful in this invention are tabular grain silver halide
emulsions. Specifically contemplated tabular grain emulsions are those in which
greater than 50 percent of the total projected area of the emulsion grains are
accounted for by tabular grains having a thickness of less than 0.3 micron (0.5
micron for blue sensitive emulsion) and an average tabularity (T) of greater than
25 (preferably greater than 100), where the term "tabularity" is employed in its art
recognized usage as
T = ECD/t2
where
ECD is the average equivalent circular diameter of the tabular grains in
micrometers and t is the average thickness in micrometers of the tabular grains.
The average useful ECD of photographic emulsions can range up to
about 10 micrometers, although in practice emulsion ECD's seldom exceed about
4 micrometers. Since both photographic speed and granularity increase with
increasing ECD's, it is generally preferred to employ the smallest tabular grain
ECD's compatible with achieving aim speed requirements.
Emulsion tabularity increases markedly with reductions in tabular
grain thickness. It is generally preferred that aim tabular grain projected areas be
satisfied by thin (t <0.2 micrometer) tabular grains. To achieve the lowest levels
of granularity it is preferred that aim tabular grain projected areas be satisfied with
ultrathin (t <0.07 micrometer) tabular grains. Tabular grain thicknesses typically
range down to about 0.02 micrometer. However, still lower tabular grain
thicknesses are contemplated. For example, Daubendiek et al U.S. Patent
4,672,027 reports a 3 mole percent iodide tabular grain silver bromoiodide
emulsion having a grain thickness of 0.017 micrometer. Ultrathin tabular grain
high chloride emulsions are disclosed by Maskasky U.S. 5,217,858.
As noted above tabular grains of less than the specified thickness
account for at least 50 percent of the total grain projected area of the emulsion. To
maximize the advantages of high tabularity it is generally preferred that tabular
grains satisfying the stated thickness criterion account for the highest conveniently
attainable percentage of the total grain projected area of the emulsion. For
example, in preferred emulsions, tabular grains satisfying the stated thickness
criteria above account for at least 70 percent of the total grain projected area. In
the highest performance tabular grain emulsions, tabular grains satisfying the
thickness criteria above account for at least 90 percent of total grain projected
area.
Suitable tabular grain emulsions can be selected from among a
variety of conventional teachings, such as those of the following:
Research Disclosure, Item 22534, January 1983, published by Kenneth Mason
Publications, Ltd., Emsworth, Hampshire P010 7DD, England; U.S. Patent Nos.
4,439,520; 4,414,310; 4,433,048; 4,643,966; 4,647,528; 4,665,012; 4,672,027;
4,678,745; 4,693,964; 4,713,320; 4,722,886; 4,755,456; 4,775,617; 4,797,354;
4,801,522; 4,806,461; 4,835,095; 4,853,322; 4,914,014; 4,962,015; 4,985,350;
5,061,069 and 5,061,616.
The emulsions can be surface-sensitive emulsions, i.e., emulsions
that form latent images primarily on the surfaces of the silver halide grains, or the
emulsions can form internal latent images predominantly in the interior of the
silver halide grains. The emulsions can be negative-working emulsions, such as
surface-sensitive emulsions or unfogged internal latent image-forming emulsions,
or direct-positive emulsions of the unfogged, internal latent image-forming type,
which are positive-working when development is conducted with uniform light
exposure or in the presence of a nucleating agent.
Photographic elements can be exposed to actinic radiation,
typically in the visible region of the spectrum, to form a latent image and can then
be processed to form a visible dye image. Processing to form a visible dye image
includes the step of contacting the element with a color developing agent to reduce
developable silver halide and oxidize the color developing agent. Oxidized color
developing agent in turn reacts with the coupler to yield a dye.
With negative-working silver halide, the processing step described
above provides a negative image. One type of such element, referred to as a color
negative film, is designed for image capture. Speed (the sensitivity of the element
to low light conditions) is usually critical to obtaining sufficient image in such
elements. Such elements may then be processed, for example, in known color
negative processes such as the Kodak C-41 process as described in The British
Journal of Photography Annual of 1988, pages 191-198. If a color negative film
element is to be subsequently employed to generate a viewable projection print as
for a motion picture, a process such as the Kodak ECN-2 process described in the
H-24 Manual availiable from Eastman Kodak Co. may be employed to provide the
color negative image on a transparent support. Color negative development times
are typically 3' 15'' or less and desirably 90 or even 60 seconds or less.
Elements destined for color reflection prints are provided on a
reflective support, typically paper, and may be optically printed using the so-called
negative-positive process where the element is exposed to light through a color
negative film which has been processed as described above. The print may then
be processed to form a positive reflection image using, for example, the Kodak
RA-4 process as described in The British Journal of Photography Annual of 1988,
Pp 198-199. Color projection prints may be processed, for example, in accordance
with the Kodak ECP-2 process as described in the H-24 Manual. Color print
development times are typically 90 seconds or less and desirably 45 or even 30
seconds or less.
A reversal element is capable of forming a positive image without
optical printing. To provide a positive (or reversal) image, the color development
step is preceded by development with a non-chromogenic developing agent to
develop exposed silver halide, but not form dye, and followed by uniformly
fogging the element to render unexposed silver halide developable. Such reversal
emulsions are typically sold with instructions to process using a color reversal
process such as the Kodak E-6 process. Alternatively, a direct positive emulsion
can be employed to obtain a positive image.
The above emulsions are typically sold with instructions to process
using the appropriate method such as the mentioned color negative (Kodak C-41),
color print (Kodak RA-4), or reversal (Kodak E-6) process.
Preferred color developing agents are
p-phenylenediamines such
as:
4-amino-N,N-diethylaniline hydrochloride, 4-amino-3-methyl-N,N-diethylaniline hydrochloride, 4-amino-3-methyl-N-ethyl-N-(2-methanesulfonamidoethyl)aniline
sesquisulfate hydrate, 4-amino-3-methyl-N-ethyl-N-(2-hydroxyethyl)aniline sulfate, 4-amino-3-(2-methanesulfonamidoethyl)-N,N-diethylaniline
hydrochloride, and 4-amino-N-ethyl-N-(2-methoxyethyl)-m-toluidine di-p-toluene sulfonic
acid.
Development is usually followed by the conventional steps of
bleaching, fixing, or bleach-fixing, to remove silver or silver halide, washing, and
drying.
The entire contents of the patent applications, patents and other
publications referred to in this specification are incorporated herein by reference.
Synthesis of Coupler
The magenta DIR couplers described in this invention can be
prepared by reactions and methods known in the organic chemistry synthesis art.
The specific synthesis of inventive compound A2 illustrates the synthesis of these
compounds. Ph is phenyl; Et is ethyl; DMF is N,N-dimethyl formamide; THF is
tetrahydrofuran; tBu is t-butyl; DCC is dicyclohexylcarbodiimide; DBU is 1,8-diazobicyclo[5.4.0]undec-7-ene
Compound 3
Compound 1 (47.8 g, 0.20 mol) was dissolved in dry DMF (350
mL) at room temperature under a nitrogen atmosphere. Ethyl bromoacetate 2
(33.4 g, 0.20 mol) was added in one portion. The mixture was stirred at room
temperature and triethylamine (20.2 g, 0.20 mol) was added dropwise over 20
minutes. The reaction mixture was stirred at room temperature for 2 hours. TLC
(silica gel; ethyl acetate/heptane, 40:60) showed 3 product spots at Rf 0.40,0.45,
and 0.50. The reaction mixture was poured with stirring into a mixture of ice and
water (800 mL) plus concentrated hydrochloric acid (80 mL). The aqueous
mixture was extracted 3 times with ethyl acetate. The extracts were combined and
were washed twice with saturated sodium chloride solution. The extracts were
dried over magnesium sulfate and were treated with Norit. The mixture was
filtered and the solvent was removed on a rotary evaporator. The resulting residue
was dissolved in hot methanol (300 mL). The hot solution was allowed to stand at
room temperature overnight. The mixture was chilled in ice and then was filtered.
The collected solid was washed with cold methanol. The product was dried in a
vacuum oven at 40° under nitrogen. This gave compound 3 as white platelets, mp
134-137°. TLC (as above) showed a single spot at Rf 0.40 and an NMR spectrum
was consistent with structure 3. Yield 21.9 g (34%).
Compound 6
Compound 4 (37.0 g, 0.109 mol) was mixed with dry acetone (250
mL) and dry THF (75 mL). The mixture was stirred at room temperature under a
nitrogen atmosphere, and thiophosgene 5 (13.8 g, 9.1 mL, 0.12 mol) was added in
one portion. The mixture was stirred at room temperature for 4 hours. TLC
(silica gel; ethyl acetate/heptane, 30:70) showed that some 4 at Rf 0.70 was still
present. More 5 (3.0 mL) was added and the mixture was stirred for an additional
19 hours. At this point TLC showed that all 4 had reacted. The reaction mixture
was poured with stifling into ice and water (1000 mL). The aqueous mixture was
extracted 3 times with ethyl acetate. The extracts were combined and were
washed twice with saturated sodium chloride solution. The extracts were dried
over magnesium sulfate and then were filtered. The solvent was removed on a
rotary evaporator. This gave compound 6 as a tan oil. TLC (as above) showed a
major spot at Rf 0.80, trace spot at Rf 0.50. Yield 41.0 g (99%).
Compound 7
Compound 3 (9.8 g, 0.030 mol) and compound 6 (12.2 g, 0.032
mol) were mixed with dry THF (150 mL). The mixture was stirred at room
temperature under a nitrogen atmosphere until the reactants dissolved. The
reaction flask was chilled in an ice-salt-acetone bath. When the pot temperature
was 0°, potassium t-butoxide (3.6 g., 0.032 mol) was added in portions over 5
minutes. The mixture was stirred in the ice bath for 30 minutes more, then it was
stirred at room temperature for 2 hours. The reaction mixture was poured into a
mixture of ice and water (600 mL) plus concentrated hydrochloric acid (50 mL).
The aqueous mixture was extracted 3 times with ethyl acetate. The extracts were
combined and were washed twice with saturated sodium chloride solution. The
extracts were dried over magnesium sulfate and then were filtered. The solvent
was removed from the filtrate on a rotary evaporator to give a tan oil. TLC (silica
gel; ethyl acetate/heptane, 40:60) showed a major spot at Rf 0.25, minor spots at Rf
0.80 and 0.40. The crude product was chromatographed over silica gel using ethyl
acetate/heptane (40:60) as the eluant. The fractions containing the Rf 0.25
component were combined and the solvent was removed on a rotary evaporator.
This gave compound 7 as a tan semi-solid. An NMR spectrum was consistent
with the structure of 7. Yield 13.6 g (64%).
Compound A2
Compound 8 (3.2 g, 0.018 mol) was mixed with dry THF (75 mL).
The mixture was stirred at room temperature under nitrogen, and triethylamine
(1.8 g, 0.018 mol) was added dropwise over 5 minutes. The resulting mixture was
stirred at room temperature for 10 minutes. A solution of compound 7 (13.0 g,
0.018 mol) in dry THF (100 mL) was added in one portion. Then a solution of
DCC (4.5 g, 0.022 mol) in dry THF (20 mL) was added in one portion. The
mixture was stirred at room temperature for 2 and 1/2 hours. TLC (silica gel;
ethyl acetate/heptane, 40:60) showed a major product spot at Rf 0.70 for the
arylhydrazone intermediate. A solution of DBU (5.5 g, 0.036 mol) in dry THF (30
mL) was added dropwise over 10 minutes. The mixture was stirred at room
temperature for 2 hours. TLC (silica gel; dichloromethane/methanol, 95:5)
showed a major product spot at Rf 0.30 (coupled magenta). The reaction mixture
was poured with stirring into a mixture of ice and water (600 mL) plus
concentrated hydrochloric acid (50 mL). The aqueous mixture was extracted 3
times with ethyl acetate. The extracts were combined and were washed twice with
saturated sodium chloride solution. The extracts were dried over magnesium
sulfate and then were filtered. Removal of the solvent afforded a tan oil whose
TLC (dichloromethane/methanol, 95:5) showed major spots at Rf 0.80 (due to
dicyclohexylthiourea) and 0.30, minor spots at Rf 0.95 and 0.50, and several trace
spots. The crude product was chromatographed over silica gel using
dichloromethane/methanol(95:5) as the eluant. The fractions containing the Rf
0.30 component were combined and the solvent was removed on a rotary
evaporator. The resulting residue was stirred in methanol (75 mL) at room
temperature for 1 and 1/2 hours. The mixture was filtered and the collected solid
was washed with cold methanol. The product was dried in a vacuum oven at room
temperature. This gave compound A2 as a beige powder, mp 100-102°. An NMR
spectrum was consistent with the structure of A2. Yield 4.9 g (35%). Anal.
Calcd. for C41H42Cl2N6O5: C, 63.98; H, 5.50; N, 10.92; Cl, 9.21. Found: C, 63.37;
H, 5.66; N, 10.68; Cl, 8.74. HPLC showed that A2 was 93.1% pure.
Photographic Examples:
Example 1.
The activity of the DIR couplers of this invention relative to
comparative DIR couplers may be evaluated by coating the DIR coupler with an
imaging coupler in a photographic element containing silver halide. The
photographic element may then be exposed and processed, and the amount of
remaining DIR and imaging couplers may be analyzed (by extraction and high
performance liquid chromatography, hplc) as a function of exposure. A plot of the
logarithm of DIR coupler remaining vs the logarithm of the imaging coupler
remaining yields a straight line whose slope equals the ratio of the reactivity of the
DIR coupler to that of the imaging coupler. It is typically desirable that the
reactivity of the DIR coupler be at least twice that of the imaging coupler so that
the DIR coupler may effectively compete for oxidized developer and efficiently
release inhibitor as a function of exposure. For these comparisons the film format
shown in Table I was used and the imaging coupler employed was M-1 having the
structure shown below. Similar measurements may be carried out with other
imaging couplers such as M-2 or M-3, also shown below. Laydowns in
parentheses in Table I are in g/sq m.
Overcoat: | Gelatin (5.38) Bis(vinylsulfonyl)methane Hardener (0.259) |
M-1 Magenta Imaging Coupler (0.559) & S-1 (0.447) & ST-1(0.112) |
Pyrazolone DIR Coupler Coated at 0.108 mmol/sq m (e.g. 0.085 A2) |
Green-Sensitized Silver Iodobromide tabular grain (1.0x0.09 µm) (1.61 Ag) |
Gelatin (2.69) |
Cellulose Acetate Support with Gel U-Coat and Antihalation Backing |
All DIR couplers were dispersed at a 1:2 weight ratio in tritolyl
phosphate (S-1, mixed isomers). Typically, dispersions were prepared by adding
an oil phase containing a 1:2:3 weight ratio of DIR coupler: S-1 : ethyl acetate to
an aqueous phase containing gelatin and the dispersing agent Alkanol XC
(Dupont) in a 10:1 weight ratio. The mixture was than passed through a colloid
mill to disperse the oil phase in the aqueous phase as small particles. On coating,
the ethyl acetate auxiliary solvent evaporates. For couplers C4 and A4
cyclohexanone was used as an auxiliary solvent due to limited solubility in ethyl
acetate. Coupler M-1 was coated with S-1 and ST-1 (see below) at a 1:0.8:0.2
weight ratio.
Film samples were exposed and processed in a standard Kodak
Flexicolor C-41 process. Extracts of M-1 and DIR coupler from various exposure
steps were analyzed by hplc and reactivities of the DIR couplers relative to coupler
M-1 were determined as described above. Relative reactivity values for
comparative couplers and DIR couplers of this invention are shown in Table II. It
is evident from the data in Table II that the DIR couplers of this invention provide
desirable high reactivities.
Pyrazolone DIR Coupler | Reactivity Relative to M-1 |
C1 (Comparative) | 1.4 |
C2 (Comparative) | 1.3 |
C4 (Comparative) | 1.3 |
A1 (Invention) | 5.7 |
A2 (Invention) | 2.5 |
A5 (Invention) | 2.0 |
A6 (Invention) | 2.0 |
A8 (Invention) | 5.0 |
A24 (Invention) | 7.0 |
A25 (Invention) | 2.7 |
Example 2.
Comparative DIR couplers and Pyrazolone DIR couplers of this
invention were coated in a format similar to that of Example 1 to assess the
stability of the various DIR couplers toward long term storage or storage at
elevated temperatures, so-called raw stock keeping. (Couplers C2 and A1 were
coated in a bilayer format similar to that of Example 3, but M-1 and DIR laydowns
are the same.) Film samples were fixed to remove silver halide. One set was
placed in a freezer at -4°C, and the other was incubated at 60°C/50% RH for 2
weeks, an accelerated test designed to simulate long term storage. The film
samples were then analyzed for remaining DIR coupler by extraction and hplc.
Table III lists the percentages of each coupler lost in the incubated samples,
relative to the freezer checks. It is desirable that losses be less than about 15% and
preferably less than 10%. The comparative couplers in Table III all show
unacceptable stability on storage. The couplers of this invention show acceptable
raw stock keeping. In Particular, couplers A1, A5, A6 and A8 show extremely
good raw stock stability.
Pyrazolone DIR Coupler | % Coupler Loss after 2 Weeks at 60°C/50% RH |
C2 (Comparative) | 25 |
C3 (Comparative) | 18 |
C4 (Comparative) | 25 (hand ctg) |
A1 (Invention) | 2 |
A2 (Invention) | 14 |
A4 (Invention) | 12 |
A5 (Invention) | 4 |
A6 (Invention) | 4 |
A8 (Invention) | 8 |
A24 (Invention) | 7 |
A25 (Invention) | 9 |
Example 3.
To illustrate the superior silver development inhibition and
interimage provided by the pyrazolone DIR couplers of this invention, they were
also evaluated in the multilayer causer/receiver format shown in Table IV.
Structures of components not given previously or in Example 4 are provided after
Table IV. Laydowns in parenthesis in Table IV are in g/m2.
Film samples were given a sensitometric white light (neutral)
exposure and processed in a standard Kodak Flexicolor C-41 process. Green
(causer) and red (receiver) status M densities vs exposure were then measured for
film A without DIR coupler, film B with comparative DIR coupler C2 and film C
containing DIR coupler A1 of this invention. Both C2 and A1 were coated at a
level of 0.161 micro moles/sq ft. Green and red gamma values were then obtained
from slopes of the plots of density vs log exposure. For high interlayer interimage
and high color correction it is desirable that a DIR coupler provide minimal
reduction in gamma in its own layer (causer gamma), but substantial gamma
reduction in receiver layers. In this case green gamma corresponds to causer
gamma and red gamma to receiver gamma. For uninhibited film A, green and red
gammas are 1.00 and 0.99, respectively. For film B with comparative coupler C2,
green and red gammas are reduced to 0.90 and 0.86, respectively. For film C with
coupler A1 of this invention, green and red gammas are reduced to 0.88 and 0.65
respectively. Thus, while both couplers C2 and A1 produce small reductions in
green causer gamma, coupler A1 provides a much larger and desirable reduction
(34%) in red receiver gamma than does C2 (13%).
OVERCOAT: | Gelatin (2.69) Bis(vinylsulfonyl)methane Hardener (0.227) |
CAUSER: | M-1 (0.43) & S-1 (0.344) & ST-1 (0.086) |
A) | No DIR Coupler (Uninhibited Check) |
B) | C2 (0.141) & S-1 (0.282) Comparative |
or C) | A1 (0.142) & S-1 (0.284) Invention |
Green-Sens. Silver Iodobromide tabular grain emulsion (0.807 Ag) |
Gelatin (2.69) |
INTERLAYER: | IS-1 (0.054) & S-1 (0.054) |
Gelatin (0.86) |
RECEIVER: | CC-1 (0.753) & S-2 (0.753) |
B-2 (0.054) & S-3 (0.054) |
IR-5 (0.022) & S-5 (0.044) |
Red-Sens. Silver Iodobromide tabular grain emulsion (0.807 Ag) |
Gelatin (2.69) |
Cellulose Acetate Support with Gel U-Coat and Antihilation Backing |
Example 4.
The multilayer film structure utilized for this example is shown
schematically in Table V. Structures of components not provided previously are
given immediately following Table V. Component laydowns are provided in units
of g/sq m unless otherwise indicated. Gelatin is used as a binder in the various
layers of the multilayer film. A similar composition may be coated on a support,
such as polyethylene naphthalate, containing a magnetic recording layer. This
film may be processed using Kodak Flexicolor C-41 chemistry to yield improved
interimage and color.