Field of the Invention
[0001] This invention relates to the silver halide photographic art and more specifically
to a photographic element and process which employ a particular combination of yellow
dye-forming couplers.
Background of the Invention
[0002] The use of t-alkylacylacetanilide couplers (Type I), such as pivaloylacetanilides,
with phenolic coupling-off groups in photographic elements is well established. However,
in combination with a Development Inhibitor Releasing (DIR) coupler, these Type I
couplers produce a photographic element with limited exposure latitude.
[0003] The term latitude is used to describe the ability of a photographic element to provide
an acceptable image across a range of exposure levels. It is believed that these Type
I couplers with phenolic coupling-off groups are not effectively balanced for competition
with the DIR coupler to form dye. To overcome the limited exposure latitude, additional
coupler laydown is required, but this added laydown of coupler dispersion with solvent,
gel and coupler results in increased light scattering and optical degradation. This
degradation is especially amplified when the scattering takes place in an uppermost
color record where the effect of scattering is transferred throughout the element.
Alternatively, the silver laydown can be increased to extend the latitude which also
leads to increased light scatter and optical degradation in the underlying layers
(once again, especially critical in an uppermost layer). In addition, yellow dye-forming
elements can be comprised of two or more layers of differing exposure sensitivities.
The exposure linearity of the combination of these two photographic layers is less
than desired with the use of Type I couplers with phenolic coupling-off groups in
combination with DIR couplers. Failure of the coupler to compete optimally with the
DIR coupler results in the speed of the underlying layer being reduced which in turn
results in a curve shape non-linearity. Correction of the resulting non-linearity
requires larger emulsions which exhibit inferior granularity.
[0004] The use of arylacylacetanilide couplers (Type II), such as benzoylacetanilides, with
heterocyclic coupling-off groups has also been used in photographic elements. Advantages
realized with the use of such Type II couplers with heterocyclic coupling-off groups
include better reactivity matching with DIR couplers (see U.S. 4,980,267). A superior
reactivity match with DIR couplers also leads to lower coupler laydown. Additionally,
improved curve linearity with smaller grain-size emulsions result when two or more
layers of differing sensitivity are coated. If the underlying of two or more layers
uses such a coupler it competes effectively with DIR couplers and results in optimal
photographic speed.
[0005] However, the use of these Type II couplers leads to problems with continued coupling
which causes increases in blue minimum density levels in seasoned, high pH bleaches.
In addition, the use of the Type II couplers in high pH color negative developers
can lead to mismatched red, green and blue contrasts. While the red and green photographic
elements respond with contrast changes to varying developer pH values, a Type II coupler
is essentially insensitive to pH levels. This mismatch results in color degradation
because the printer is unable to compensate for three individual records because the
contrasts of the three individual records do not vary synchronously.
[0006] Combination of Type I couplers with either heterocyclic coupling-off groups or phenolic
coupling-off groups without a solubilizing substituent together with Type II couplers
with heterocyclic coupling-off groups are known in color negative films. For example,
the following combination has been employed in a product:

CP-1 was present at 57 mol % and CP-2 at 43 mol % and the combination was employed
in a single blue-sensitive layer. Coupler CP-1 does not contain a solubilizing group
as in the invention. The combination of these two couplers did not provide balanced
reactivity and therefore linearity, laydown, and color rendition were not optimum.
[0007] The lower reactivity of the Type I couplers with heterocyclic coupling-off groups
results in a situation where reactivity matches with DIR couplers are not optimized,
and, thus, laydowns are higher than necessary. In order to provide the needed exposure
latitude, additional coupler laydown is required. Additional coupler dispersion with
solvent, gel and coupler results in layer thickness increases and subsequent light
scattering and optical degradation and the same problems present in the art for the
use of a Type I coupler only are realized.
[0008] It is a problem to be solved to provide a photographic element and process which
provides an improved linearity of response in the blue record across the range of
exposures while maintaining the desired level of sharpness.
Summary of the Invention
[0009] A photographic element and process employ a light sensitive photographic silver halide
layer sensitized to blue light and having associated therewith a combination of at
least two yellow dye-forming couplers each containing an acylacetanilide parent, one
of which comprises a phenolic coupling-off group containing a solubilizing substituent,
and the other of which is a benzoylacetanilide comprising a heterocyclic coupling-off
group.
[0010] By combining the use of a Type I coupler comprising a phenolic coupling-off group
containing a solubilizing substituent together with a Type II coupler comprising a
heterocyclic coupling-off group, significant benefits are realized in terms of linearity
and sharpness while minimizing the limitations that these separate types would normally
cause when used alone and such results are generally obtained at lower laydown levels
then heretofore achievable.
Detailed Description of the Invention
[0011] The photographic element of the invention comprises at least two yellow image-dye
forming couplers which suitably have the respective formulas:

wherein X has the formula -OPh(L)
nSol, and wherein R is a substituted or unsubstituted aryl group or a fully substituted
carbon atom, each Ph is a phenyl ring, independently substituted or not, Sol is a
water solubilizing substituent, L is a divalent group linking the phenyl ring and
Sol, n is 0 or 1, and Y is a heterocyclic ring, substituted or not.
[0012] More suitable R groups are phenyl, t-butyl, t-pentyl, t-octyl, and adamantyl with
phenyl and t-butyl most suitable.
[0013] The Ph is a phenyl group which may be optionally substituted. Any substituents may
be suitable such as those illustrated in the example couplers.
[0014] L is a linking group which may or may not be present. Such a group does not necessarily
play any major role in the photographic properties but may affect properties such
as ballasting. Examples of suitable linking groups are:

wherein Z represents -O-; -SO₂-; -S- ;or -NR
bSO₂-and each R, R', R
a and R
b independently represents an alkyl group, substituted or not, and R
b may be hydrogen. Further, n, p, and q may be 0 or 1, signifying the presence or absence
of the linking group and the presence or absence of the specified linking group components.
m may be from 0 to 4.
The Sol group is a water solubilizing substituent. Any strongly polar or readily ionizing
group or one highly susceptible to hydrogen bonding can have this effect as is well-known.
Suitable general examples are:
-OH, -NHSO₂R, -NHCOR, -NHCOCF₃, -NHCOOR, -NR₂, -NHCONR₂, -CONR₂, -CONHSO₂R, -SO₃H,
-CO₂R, -(OR)
n, -OSO₂R, -P(O)0R₂, and

wherein each R is an independently selected substituent or hydrogen, and n is 0
to 3.
[0015] Examples of suitable specific solubilizing substituents are:
-COOH; -COOCH₃; -COOC₂H₅; -NHSO₂CH₃; -SO₃H; -OH; -SO₂NHCH₃; -SO₂NH₂;

[0016] Illustrative examples of Type I couplers are:

The generic definition of the Type I parent group is broad enough to include all
of those parents of the Type II parents. On the other hand, the Type II parent is
more narrowly defined. As detailed, the coupling-off groups for the two types are
mutually distinct.
[0017] Illustrative examples of Type II couplers are as follows:

The phenolic coupling-off group in the Type I coupler may, if desired, contain
one or more substituents on the phenoxy ring aside from the substituent containing
the solubilizing group. These substituents may be any which are useful in the photographic
arts as described hereafter. Illustrative examples of the phenolic coupling-off groups
useful on the Type I couplers are as follows:

The Y group in formula II represent a heterocyclic coupling-off group. Such a group
is typically connected through a carbon or nitrogen atom in the heterocycle. Nitrogen
is the preferred connecting link and in such case, Y is selected from the group consisting
of substituted and unsubstituted imidazole, pyrazole, and heterocyclic compounds represented
by the formula:

wherein z represents the atoms necessary to complete a heterocyclic ring. The compounds
having this formula are typically hydantoin or succinimide compounds. In one specific
embodiment, Y may be represented by the formula:

wherein W is -O-, -S-, -N(R³)-, or -C(R⁴)(R⁵)-; R¹ is H, or substituted or unsubstituted
alkyl, alkoxy, phenyl, or phenoxy; R² and R⁵ are independently H or substituted or
unsubstituted alkyl; R³ is substituted or unsubstituted alkyl or phenyl; and R⁴ is
H or substituted or unsubstituted alkyl or alkoxy.
[0018] In one more specific embodiment of the above formula, W is -NR³; R¹ is H, or substituted
or unsubstituted alkyl or alkoxy; R² is H; and R³ is substituted or unsubstituted
alkyl. In particular, R¹ is -OC₂H₅, R² is H and R³ is -CH₂-phenyl. In another specific
embodiment, W is -C(R⁴)(R⁵) with R¹, R², R⁴, and R⁵ defined as above.
[0019] Illustrative examples of the Type II heterocyclic coupling-off groups are as follows:

Suitable combinations of parent and coupling-off groups for Type I and Type II
couplers are as shown in Tables I and II.
Table I
Type I Coupler Parent/Coupling-off Group Combinations |
No. |
Combination |
No. |
Combination |
No. |
Combination |
1 |
IK/f |
2 |
IK/a |
3 |
IK/d |
4 |
IG/f |
5 |
II/a |
6 |
IC/d |
7 |
IB/e |
8 |
IC/i |
9 |
ID/h |
10 |
IE/g |
11 |
IF/k |
12 |
IG/b |
13 |
II/c |
14 |
IG/j |
15 |
IH/l |
16 |
IA/h |
17 |
IA/d |
18 |
IJ/b |
19 |
IH/a |
20 |
IJ/i |
21 |
IB/j |
22 |
ID/e |
23 |
IF/i |
24 |
IE/k |
Table II
Type II Coupler Parent/Coupling-off Group Combinations |
No. |
Combination |
No. |
Combination |
No. |
Combination |
1 |
IIA/a |
2 |
IIA/i |
3 |
IIA/b |
4 |
IIB/d |
5 |
IIB/a |
6 |
IIB/e |
7 |
IIB/b |
8 |
IIC/i |
9 |
IIC/c |
10 |
IIC/f |
11 |
IIC/a |
12 |
IID/g |
13 |
IID/i |
14 |
IID/b |
15 |
IIA/c |
16 |
IIE/a |
17 |
IIE/h |
18 |
IIE/i |
19 |
IIF/b |
20 |
IIF/c |
21 |
IIG/a |
22 |
IIG/d |
23 |
IIH/e |
24 |
IIH/b |
25 |
IIC/j |
26 |
IIA/k |
27 |
IID/l |
[0020] As used herein, the term substituent, unless otherwise specifically stated, has a
broad definition. The substituent may be, for example, halogen, such as chlorine,
bromine or fluorine; nitro; hydroxyl; cyano; and -CO₂H and its salts; and groups which
may be further substituted, such as alkyl, including straight or branched chain alkyl,
such as methyl, trifluoromethyl, ethyl,
t-butyl, 3-(2,4-di-t-amylphenoxy) 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-pentylphenoxy)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-tetradecyl-pyrrolin-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-dodecylphenylcarbonylamino,
p-toluylcarbonylamino, 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-toluylureido, N-(
m-hexadecylphenyl)ureido, N,N-(2,5-di-
t-pentylphenyl)-N'-ethylureido; and
t-butylcarbonamido; sulfonamido, such as methylsulfonamido, benzenesulfonamido,
p-toluylsulfonamido,
p-dodecylbenzenesulfonamido, N-methyltetradecylsulfonamido, N,N-dipropylsulfamoylamino,
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-toluylsulfonyl; sulfonyloxy, such as dodecylsulfonyloxy, and hexadecylsulfonyloxy;
sulfinyl, such as methylsulfinyl, octylsulfinyl, 2-ethylhexylsulfinyl, dodecylsulfinyl,
hexadecylsulfinyl, phenylsulfinyl, 4-nonylphenylsulfinyl, and
p-toluylsulfinyl; 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;
azo, such as phenylazo and naphthylazo; 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.
[0021] The particular substituents used may be selected to attain the desired photographic
properties for a specific application and can include, for example, hydrophobic groups,
solubilizing groups, blocking groups, etc. Generally, the above groups and substituents
thereof may typically include those having 1 to 30 carbon atoms and usually less than
24 carbon atoms, but greater numbers are possible depending on the particular substituents
selected. Moreover, as indicated, the substituents may themselves be suitably substituted
with any of the above groups.
[0022] 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, 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.
[0023] To control the migration of various components, it may be desirable to include a
high molecular weight hydrophobe or "ballast" group in the component molecule. Representative
ballast groups include substituted or unsubstituted alkyl or aryl groups containing
8 to 42 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, arysulfonyl,
sulfonamido, and sulfamoyl groups wherein the substituents typically contain 1 to
42 carbon atoms. Such substituents can also be further substituted.
[0024] 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.
[0025] 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.
[0026] 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.
[0027] In the following discussion of suitable materials for use in the emulsions and elements
of this invention, reference will be made to
Research Disclosure, December 1989, Item 308119, available as described above, which will be identified
hereafter 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.
[0028] The silver halide emulsions employed in the elements of this invention can be either
negative-working or positive-working. Suitable emulsions and their preparation as
well as methods of chemical and spectral sensitization are described in Sections I
through IV. Color materials and development modifiers are described in Sections VII
and XXI. Vehicles are described in Section IX, and various additives such as brighteners,
antifoggants, stabilizers, light absorbing and scattering materials, hardeners, coating
aids, plasticizers, lubricants and matting agents are described , for example, in
Sections V, VI, VIII, X, XI, XII, and XVI. Manufacturing methods are described in
Sections XIV and XV, other layers and supports in Sections XIII and XVII, processing
methods and agents in Sections XIX and XX, and exposure alternatives in Section XVIII.
[0029] 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.
[0030] With negative-working silver halide, the processing step described above provides
a negative image. The described elements can be processed in the known C-41 color
process as described in The British Journal of Photography Annual of 1988, pages 191-198.
[0031] 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-(β-(methanesulfonamido) ethyl)aniline sesquisulfate
hydrate,
4-amino-3-methyl-N-ethyl-N-(β-hydroxyethyl)aniline sulfate,
4-amino-3-β-(methanesulfonamido)ethyl-N,N-diethylaniline hydrochloride and
4-amino-N-ethyl-N-(2-methoxyethyl)-m-toluidine di-p-toluene sulfonic acid.
[0032] Development is usually followed by the conventional steps of bleaching, fixing, or
bleach-fixing, to remove silver or silver halide, washing, and drying.
Examples
[0033] The following examples will serve to better describe the invention. The formulas
for the component materials are provided following the examples.
[0034] A color photographic recording material (Photographic Sample 101) for color negative
development was prepared by applying the following layers in the given sequence to
a transparent support of cellulose triacetate. The quantities of silver halide are
given in g of silver per m². The quantities of other materials are given in g per
m².
Layer 1 {Antihalation Layer} black colloidal silver sol containing 0.22 g of silver
with 2.44 g gelatin.
Layer 2 {First (least) Red-Sensitive Layer} Red sensitized silver iodobromide emulsion
[1.3 mol % iodide, average grain diameter 0.55 microns, average thickness 0.08 microns]
at 0.43 g, red sensitized silver iodobromide emulsion [4 mol % iodide, average grain
diameter 1.0 microns, average thickness 0.09 microns] at 0.43 g, cyan dye-forming
image coupler C-1 at 0.56 g, cyan dye-forming masking coupler CM-1 at 0.028 g, Bleach
Accelerator Releasing (BAR) compound B-1 at 0.039 g with gelatin at 1.83 g.
Layer 3 {Second (more) Red-Sensitive Layer} Red sensitive silver iodobromide emulsion
[4 mol % iodide, average grain diameter 1.3 microns, average grain thickness 0.12
microns] at 0.72 g, cyan dye-forming image coupler C-1 at 0.23 g, cyan dye-forming
masking coupler CM-1 at 0.022 g, DIR compound D-1 at 0.011 g with gelatin at 1.66
g.
Layer 4 {Third (most) Red-Sensitive Layer} Red sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 2.6 microns, average grain thickness 0.13
microns] at 1.11 g, cyan dye-forming image coupler C-1 at 0.13 g, cyan dye-forming
masking coupler CM-1 at 0.033 g, DIR compound D-1 at 0.022 g, DIR compound D-2 at
0.050 g with gelatin at 1.36 g.
Layer 5 {Interlayer} Yellow dye material YD-1 at 0.11 g and 1.33 g of gelatin.
Layer 6 {First (least) Green-Sensitive Layer} Green sensitized silver iodobromide
emulsion [1.3 mol % iodide, average grain diameter 0.55 microns, average grain thickness
0.08 microns] at 0.59 g, green sensitized silver iodobromide emulsion [4 mol % iodide,
average grain diameter 1.0 microns, average grain thickness 0.09 microns] at 0.34
g, magenta dye-forming image coupler M-1 at 0.24 g, magenta dye-forming masking coupler
MM-1 at 0.067 g with gelatin at 1.78 g.
Layer 7 {Second (more) Green-Sensitive Layer} Green sensitized silver iodobromide
emulsion [4 mol % iodide, average grain diameter 1.25 microns, average grain thickness
0.12 microns] at 1.00 g, magenta dye-forming image coupler M-1 at 0.089 g, magenta
dye-forming masking coupler MM-1 at 0.067 g, DIR compound D-1 at 0.024 g, DIR compound
D-3 at 0.006 g with gelatin at 1.48 g.
Layer 8 {Third (most) Green-Sensitive Layer} Green sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 2.16 microns, average grain thickness 0.12
microns] at 1.00 g, magenta dye-forming image coupler M-1 at 0.067 g, magenta dye-forming
masking coupler MM-1 at 0.056 g, DIR compound D-3 at 0.006 g, DIR compound D-4 at
0.018 g with gelatin at 1.33 g.
Layer 9 {Interlayer} Yellow dye material YD-2 at 0.11 g with 1.33 g gelatin.
Layer 10 {First (less) Blue-Sensitive Layer} Blue sensitized silver iodobromide emulsion
[1.3 mol % iodide, average grain diameter 0.55, average grain thickness 0.08 microns]
at 0.22 g, blue sensitized silver iodobromide emulsion [6 mol % iodide, average grain
diameter 1.0 microns, average grain thickness 0.26 microns] at 0.58 g, yellow dye-forming
image coupler Y-1 at 0.29 g, yellow dye forming image coupler Y-2 at 0.72 g, DIR compound
D-5 at 0.067 g, BAR compound B-1 at 0.003 g with gelatin at 2.6 g.
Layer 11 {Second (more) Blue-Sensitive Layer} Blue sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 3.0 microns, average grain thickness 0.14
microns] at 0.23 g, blue sensitized silver iodobromide emulsion [9 mol % iodide, average
grain diameter 1.0 microns] at 0.59 g, yellow dye-forming image coupler Y-1 at 0.092
g, yellow dye-forming image coupler Y-2 at 0.23 g, DIR compound D-5 at 0.051 g, BAR
compound B-1 at 0.006 g with gelatin at 1.97 g.
Layer 12 {Protective Layer} 0.111 g of dye UV-1, 0.111 g of dye UV-2, unsensitized
silver bromide Lippmann emulsion at 0.222 g, Cyan dye material CD-1 at 0.007 g with
gelatin at 1.11 g.
Layer 13 {Protective Layer} Gelatin at 0.92 g.
[0035] This film was hardened at coating with 2% by weight to total gelatin of hardener
H-1. Surfactants, coating aids, oxidized developer scavengers, soluble absorber dyes
and stabilizers were added to the various layers of this sample as is commonly practiced
in the art.
[0036] Photographic Sample 102 was prepared like Photographic Sample 101 except for changes
in Layers 10 and 11. In Layer 10 yellow dye-forming coupler Y-2 was omitted and yellow
dye-forming coupler Y-1 was coated at 0.78 g. In Layer 11 yellow dye-forming coupler
Y-2 was omitted and yellow dye-forming coupler Y-1 was coated at 0.22 g.
Photographic Sample 103 was prepared by applying the following layers in the given
sequence to a transparent support of cellulose triacetate. The quantities of silver
halide are given in g of silver per m². The quantities of other materials are given
in g per m².
Layer 1 {Antihalation Layer} black colloidal silver sol containing 0.22 g of silver,
Cyan dye material CD-2 at 0.033 g, Magenta dye material MD-1 at 0.022 g, Yellow dye
material YD-3 at 0.133 g with 2.44 g gelatin.
Layer 2 {First (least) Red-Sensitive Layer} Red sensitized silver iodobromide emulsion
[1.3 mol % iodide, average grain diameter 0.55 microns, average thickness 0.08 microns]
at 0.28 g, red sensitized silver iodobromide emulsion [4 mol % iodide, average grain
diameter 1.0 microns, average thickness 0.09 microns] at 0.33 g, cyan dye-forming
image coupler C-1 at 0.56 g, BAR compound B-1 at 0.089 g with gelatin at 1.83 g.
Layer 3 {Second (more) Red-Sensitive Layer} Red sensitive silver iodobromide emulsion
[4 mol % iodide, average grain diameter 1.3 microns, average grain thickness 0.12
microns] at 0.56 g, cyan dye-forming image coupler C-1 at 0.23 g, cyan dye-forming
masking coupler CM-1 at 0.022 g, DIR compound D-2 at 0.050 g, BAR compound B-1 at
0.003 g with gelatin at 1.66 g.
Layer 4 {Third (most) Red-Sensitive Layer} Red sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 2.6 microns, average grain thickness 0.13
microns] at 1.22 g, cyan dye-forming image coupler C-1 at 0.17 g, cyan dye-forming
masking coupler CM-1 at 0.050 g, DIR compound D-6 at 0.003 g, DIR compound D-2 at
0.050 g, BAR compound B-1 at 0.002 g with gelatin at 1.36 g.
Layer 5 {Interlayer} 1.33 g of gelatin.
Layer 6 {First (least) Green-Sensitive Layer} Green sensitized silver iodobromide
emulsion [4 mol % iodide, average grain diameter 1.0 microns, average grain thickness
0.09 microns] at 0.78 g, magenta dye-forming image coupler M-2 at 0.067 g, magenta
dye-forming image coupler M-3 at 0.22 g, BAR compound B-2 at 0.033 g with gelatin
at 1.78 g.
Layer 7 {Second (more) Green-Sensitive Layer} Green sensitized silver iodobromide
emulsion [4 mol % iodide, average grain diameter 1.25 microns, average grain thickness
0.12 microns] at 1.00 g, magenta dye-forming image coupler M-2 at 0.028 g, magenta
dye-forming image coupler M-3 at 0.089 g, BAR compound B-1 at 0.003 g, magenta dye-forming
masking coupler MM-1 at 0.089 g, DIR compound D-4 at 0.022 g with gelatin at 1.48
g.
Layer 8 {Third (most) Green-Sensitive Layer} Green sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 2.16 microns, average grain thickness 0.12
microns] at 1.00 g, magenta dye-forming image coupler M-2 at 0.030 g, magenta dye-forming
image coupler M-3 at 0.096 g, BAR compound B-1 at 0.003 g, magenta dye-forming masking
coupler MM-1 at 0.044 g, DIR compound D-3 at 0.008 g, DIR compound D-4 at 0.008 g
with gelatin at 1.33 g.
Layer 9 {Interlayer} Yellow dye material YD-2 at 0.11 g with 1.33 g gelatin.
Layer 10 {First (less) Blue-Sensitive Layer} Blue sensitized silver iodobromide emulsion
[1.3 mol % iodide, average grain diameter 0.55, average grain thickness 0.08 microns]
at 0.11 g, blue sensitized silver iodobromide emulsion [4.1 mol % iodide, average
grain diameter 0.85, average grain thickness 0.09 microns] at 0.26 g, blue sensitized
silver iodobromide emulsion [4.1 mol % iodide, average grain diameter 1.32, average
grain thickness 0.14 microns] at 0.26 g, yellow dye-forming image coupler Y-1 at 0.22
g, yellow dye forming image coupler Y-2 at 0.69 g, DIR compound D-5 at 0.049 g, BAR
compound B-1 at 0.003 g with gelatin at 2.6 g.
Layer 11 {Second (more) Blue-Sensitive Layer} Blue sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 3.0 microns, average grain thickness 0.14
microns] at 0.39 g, blue sensitized silver iodobromide emulsion [9 mol % iodide, average
grain diameter 1.0 microns] at 0.39 g, yellow dye-forming image coupler Y-1 at 0.065
g, yellow dye-forming image coupler Y-2 at 0.20 g, DIR compound D-5 at 0.044 g, BAR
compound B-1 at 0.006 g with gelatin at 1.97 g.
Layer 12 {Protective Layer} 0.111 g of dye UV-1, 0.111 g of dye UV-2, unsensitized
silver bromide Lippmann emulsion at 0.222 g, Cyan dye material CD-2 at 0.006 g, Magenta
dye material MD-2 at 0.001 g with gelatin at 1.11 g.
Layer 13 {Protective Layer} Gelatin at 0.92 g.
This film was hardened at coating with 2% by weight to total gelatin of hardener
H-1. Surfactants, coating aids, oxidized developer scavengers, soluble absorber dyes
and stabilizers were added to the various layers of this sample as is commonly practiced
in the art.
[0037] Photographic Sample 104 was prepared like Photographic Sample 103 except for changes
in Layers 10 and 11. In Layer 10 yellow dye-forming coupler Y-1 was omitted and yellow
dye-forming coupler Y-2 was coated at 0.94 g. In Layer 11 yellow dye-forming coupler
Y-1 was omitted and yellow dye-forming coupler Y-2 was coated at 0.28 g.
[0038] Photographic Sample 105 was prepared like Photographic Sample 103 except for changes
in Layers 10 and 11. In Layer 10 yellow dye-forming coupler Y-2 was omitted and yellow
dye-forming coupler Y-3 was added at 0.89 g. In Layer 11 yellow dye-forming coupler
Y-2 was omitted and yellow dye-forming coupler Y-3 was coated at 0.26 g.
[0039] Photographic Sample 106 was prepared like Photographic Sample 103 except for Layers
10 and 11. In Layer 10, the blue sensitized silver iodobromide emulsion [4.1 mol %
iodide, average grain diameter 0.85, average grain thickness 0.09 microns] was coated
at 0.28 g and yellow dye-forming coupler Y-2 was coated at 0.72 g. In Layer 11, the
yellow dye-forming coupler Y-2 was coated at 0.21 g.
[0040] Photographic Sample 107 was prepared like Photographic Sample 106 except for changes
in Layers 10 and 11. In Layer 10 yellow dye-forming coupler Y-1 was omitted and yellow
dye-forming coupler Y-2 was coated at 0.94 g. In Layer 11 yellow dye-forming coupler
Y-1 was omitted and yellow dye-forming coupler Y-2 was coated at 0.28 g.
[0041] Photographic Sample 108 was prepared by applying the following layers in the given
sequence to a transparent support of cellulose triacetate. The quantities of silver
halide are given in g of silver per m². The quantities of other materials are given
in g per m².
Layer 1 {Antihalation Layer} black colloidal silver sol containing 0.156 g of silver,
Cyan dye material CD-2 at 0.033 g, Magenta dye material MD-1 at 0.021 g, Yellow dye
material YD-3 at 0.104 g with 2.44 g gelatin.
Layer 2 {First (least) Red-Sensitive Layer} Red sensitized silver iodobromide emulsion
[1.3 mol % iodide, average grain diameter 0.55 microns, average thickness 0.08 microns]
at 0.47 g, red sensitized silver iodobromide emulsion [4 mol % iodide, average grain
diameter 1.0 microns, average thickness 0.09 microns] at 0.46 g, cyan dye-forming
image coupler C-1 at 0.56 g, cyan dye-forming masking coupler CM-1 at 0.033 g, BAR
compound B-1 at 0.039 g with gelatin at 1.83 g.
Layer 3 {Second (more) Red-Sensitive Layer} Red sensitive silver iodobromide emulsion
[4 mol % iodide, average grain diameter 1.3 microns, average grain thickness 0.12
microns] at 0.72 g, cyan dye-forming image coupler C-1 at 0.26 g, cyan dye-forming
maskÿ g coupler CM-1 at 0.022 g, DIR compound D-1 at 0.011 g with gelatin at 1.66
g.
Layer 4 {Third (most) Red-Sensitive Layer} Red sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 2.6 microns, average grain thickness 0.13
microns] at 1.11 g, cyan dye-forming image coupler C-1 at 0.13 g, cyan dye-forming
masking coupler CM-1 at 0.033 g, DIR compound D-1 at 0.024 g, DIR compound D-2 at
0.050 g with gelatin at 1.36 g.
Layer 5 {Interlayer} Yellow dye material YD-1 at 0.11 g and 1.33 g of gelatin.
Layer 6 {First (least) Green-Sensitive Layer} Green sensitized silver iodobromide
emulsion [1.3 mol % iodide, average grain diameter 0.55 microns, average grain thickness
0.08 microns] at 0.62 g, green sensitized silver iodobromide emulsion [4 mol % iodide,
average grain diameter 1.0 microns, average grain thickness 0.09 microns] at 0.32
g, magenta dye-forming image coupler M-1 at 0.24 g, magenta dye-forming masking coupler
MM-1 at 0.067 g with gelatin at 1.78 g.
Layer 7 {Second (more) Green-Sensitive Layer} Green sensitized silver iodobromide
emulsion [4 mol % iodide, average grain diameter 1.25 microns, average grain thickness
0.12 microns] at 1.00 g, magenta dye-forming image coupler M-1 at 0.091 g, magenta
dye-forming masking coupler MM-1 at 0.067 g, DIR compound D-1 at 0.024 g with gelatin
at 1.48 g.
Layer 8 {Third (most) Green-Sensitive Layer} Green sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 2.16 microns, average grain thickness 0.12
microns] at 1.00 g, magenta dye-forming image coupler M-1 at 0.072 g, magenta dye-forming
masking coupler MM-1 at 0.056 g, DIR compound D-3 at 0.008 g, DIR compound D-4 at
0.011 g with gelatin at 1.33 g.
Layer 9 {Interlayer} Yellow dye material YD-2 at 0.11 g with 1.33 g gelatin.
Layer 10 {First (less) Blue-Sensitive Layer} Blue sensitized silver iodobromide emulsion
[1.3 mol % iodide, average grain diameter 0.55, average grain thickness 0.08 microns]
at 0.24 g, blue sensitized silver iodobromide emulsion [6 mol % iodide, average grain
diameter 1.0 microns, average grain thickness 0.26 microns] at 0.61 g, yellow dye-forming
image coupler Y-1 at 0.29 g, yellow dye forming image coupler Y-2 at 0.72 g, cyan
dye-forming coupler C-1 at 0.016 g, DIR compound D-5 at 0.067 g, BAR compound B-1
at 0.003 g with gelatin at 2.6 g.
Layer 11 {Second (more) Blue-Sensitive Layer} Blue sensitized silver iodobromide emulsion
[4 mol % iodide, average grain diameter 3.0 microns, average grain thickness 0.14
microns] at 0.23 g, blue sensitized silver iodobromide emulsion [9 mol % iodide, average
grain diameter 1.0 microns] at 0.59 g, yellow dye-forming image coupler Y-1 at 0.090
g, yellow dye-forming image coupler Y-2 at 0.23 g, cyan dye-forming coupler at 0.022
g, DIR compound D-5 at 0.051 g, BAR compound B-1 at 0.006 g with gelatin at 1.97 g.
Layer 12 {Protective Layer} 0.111 g of dye UV-1, 0.111 g of dye UV-2, unsensitized
silver bromide Lippmann emulsion at 0.222 g with gelatin at 1.11 g.
Layer 13 {Protective Layer} Gelatin at 0.92 g.
This film was hardened at coating with 2% by weight to total gelatin of hardener
H-1. Surfactants, coating aids, oxidized developer scavengers, soluble absorber dyes
and stabilizers were added to the various layers of this sample as is commonly practiced
in the art.
[0042] Photographic Sample 109 was prepared like Photographic Sample 108 except for changes
in Layers 10 and 11. In Layer 10 yellow dye-forming coupler Y-2 was omitted and yellow
dye-forming coupler Y-3 was added at 0.87 g. In Layer 11 yellow dye-forming coupler
Y-2 was omitted and yellow dye-forming coupler Y-3 was coated at 0.27 g.
[0043] TABLES 1 and 2 show the photographic responses associated with Photographic Samples
101 and 103 relative to three examples of prior art (Photographic Samples 102, 104
and 105). Each formulation is processed through two developers. These developers have
been pH adjusted to provide pH values which are high (10.15) or low (9.95) of standard
developer aim pH, 10.04. A percentage contrast change is used to reflect the effect
on contrast of pH variations from 9.95 to 10.15.
TABLE 1
Image CouplerLevels (g/sq m) by Layer |
% Contrast Change (pH =10.15/ pH = 9.95) |
Photographic Sample Number |
Most Sensitive Y-1/Y-2 |
Least Sensitive Y-1/Y-2 |
Red |
Green |
Blue |
|
0.215/0 |
0.753/0 |
10.7 |
5.8 |
-1.4 |
102(C) |
0.089/0.226 |
0.280/0.700 |
9.3 |
11.7 |
14.1 |
101(Inv) |
[0044] In the first formulation, all Type II parents with Type II heterocyclic coupling-off
groups, the blue layer contrast is invariant. This insensitivity leads to a mismatch
with the red and green contrasts, which both increase with increasing developer pH.
In the second formulation, a combination of a Type I parent and Type I phenolic coupling-off
group and a Type II parent and coupling-off group, the blue layer contrast covaries
with the other two records. One of the advantages of this covariation is better print
quality as the printer algorithms are able to adjust for the covarying contrasts of
all 3 records. In the first formulation, the contrast mismatch prevents proper printing.
TABLE 2
Image CouplerLevels (g/sq m) by Layer |
% Contrast Change (pH = 10.15/ pH = 9.95) |
Photographic Sample Number |
Most Sensitive Y-1/Y-2 or Y-3 |
Least Sensitive Y-1/Y-2 or Y-3 |
Red |
Green |
Blue |
|
0/0.268 0/Y-2 |
0/0.913 0/Y-2 |
10.4 |
24.7 |
9.5 |
104(C) |
0.063/0.253 Y-1/Y-3 |
0.215/0.859 Y-1/Y-3 |
6.5 |
22.9 |
11.7 |
105(C) |
0.063/0.196 Y-1/Y-2 |
0.215/0.666 Y-1/Y-2 |
11.1 |
29.9 |
14.7 |
103(Inv) |
[0045] The three formulations shown in TABLE 2 covary in all 3 color records allowing for
better printing relative to a photographic element containing a single Type II yellow
image coupler (TABLE 1). This advantage in two of the examples is realized despite
the presence of some Type II coupler (Y-1). The use of Type I coupler (Y-3) with a
heterocyclic (Type II) coupling off group, however, requires a greater laydown with
its accompanying layer thickness increase and light scattering characteristics. The
additional laydown is also more expensive and creates added environmental and disposal
problems.
[0046] Tables 3-5 show blue minimum densities associated with similar formulations, Photographic
Samples 101, 106 and 108. Each formulation is shown with two bleaches. These bleaches
have been pH adjusted to provide pH values of 4.75, (standard PDTA bleach pH) or 5.25,
(standard PDTA/EDTA bleach pH), and bleaches which are 0.75 pH units higher. The unexposed
color negative film is then processed through these bleaches, and the resulting blue
density is measured.
TABLE 3
Image Coupler Levels (g/sq m) by Layer |
Blue Minimum Density |
Photographic Sample Number |
Most Sensitive Y-1/Y-2 |
Least Sensitive Y-1/Y-2 |
Fresh PDTA Bleach @ pH = 4.75 |
Fresh PDTA Bleach @ pH = 5.50 |
|
0.215/0 |
0.753/0 |
0.970 |
1.043 |
102(C) |
0.089/0.226 |
0.280/0.700 |
0.957 |
0.997 |
101(Inv) |
[0047] In the first formulation, all Type II coupler, the blue layer minimum density increases
with pH growth. In the second formulation, Type I coupler with phenolic coupling-off
group and Type II coupler with heterocyclic coupling-off group, the blue layer minimum
density growth is reduced.
TABLE 4
Image Coupler Levels (g/sq m) by Layer |
Blue Minimum Density |
Photographic Sample Number |
Most Sensitive Y-1/Y-2 |
Least Sensitive Y-1/Y-2 |
Fresh PDTA/EDTA Bleach @ pH = 5.25 |
Fresh PDTA/EDTA Bleach @ pH = 6.00 |
|
0/0.268 |
0/0.913 |
0.853 |
0.892 |
106(C) |
0.063/0.205 |
0.215/0.698 |
0.874 |
0.964 |
107(Inv) |
TABLE 5
Image Coupler Levels (g/sq m) by Layer |
Blue Minimum Density |
Photographic Sample Number |
Most Sensitive Y-1/Y-2 or Y-3 |
Least Sensitive Y-1/Y-2 or Y-3 |
Fresh PDTA/EDTA Bleach @ pH = 5.25 |
Fresh PDTA/EDTA Bleach @ pH = 6.00 |
|
0.087/0.285 Y-1/Y-3 |
0.279/0.913 Y-1/Y-3 |
1.043 |
1.085 |
108(C) |
0.087/0.218 Y-1/Y-2 |
0.279/0.698 Y-1/Y-2 |
1.059 |
1.136 |
109(Inv) |
[0048] The continued coupling of a combination of Type I coupler with a Type I phenolic
coupling off group and Type II coupler with a Type II heterocyclic coupling-off group
is intermediate between the Y-1 (Table 3) and Y-2 (Table 4) individually. Relative
to a combination of a Type I parent with a Type II coupling-off group and a Type II
parent with a Type II coupling-off group, this combination gives a slightly higher
blue minimum density growth with elevation in bleach pH. However, much lower laydowns
are realized with the coupler combination of the invention (TABLE 5).
[0049] TABLES 6 and 7 show latitude measurements for Photographic Samples 101 and 103 relative
to prior art positions (Photographic Samples 102, 104 and 105). Latitude was calculated
as the log E exposure range over which the contrast remains above 0.60. A white light
exposure through a step-wise gradient tablet followed by standard color negative processing
was used.
TABLE 6
Image Coupler Levels (g/sq m) by Layer |
Blue Layer Latitude |
Photographic Sample Number |
Most Sensitive Y-1/Y-2 or Y-3 |
Least Sensitive Y-1/Y-2 or Y-3 |
|
|
0/0.268 /Y-2 |
0/0.913 /Y-2 |
2.46 |
104(C) |
0.063/0.253 Y-1/Y-3 |
0.215/0.859 Y-1/Y-3 |
2.62 |
105(C) |
0.063/0.196 Y-1/Y-2 |
0.215/0.666 Y-1/Y-2 |
2.54 |
103(Inv) |
[0050] Comparing samples 103 and 104, the table shows the advantage in exposure latitude
for a combination of Type I and Type II couplers versus a Type I coupler alone. The
use of another comparison coupler combination in the form of a Type I coupler with
Type II coupling off group (Y-3) in conjunction with a Type II coupler (Y-1), as in
Sample 105, results in improved latitude but requires a much greater laydown with
its accompanying layer thickness increase and corresponding unfavorable light scattering
characteristics as compared to Sample 103.
TABLE 7
Image Coupler Levels (g/sq m) by Layer |
Blue Layer Latitude |
Photographic Sample Number |
Most Sensitive Y-1/Y-2 |
Least Sensitive Y-1/Y-2 |
|
|
0.215/0 |
0.753/0 |
1.87 |
102(C) |
0.089/0.226 |
0.280/0.700 |
2.06 |
101(Inv) |
[0051] The two formulations show the advantage in exposure latitude for a combination of
Type I and Type II couplers relative to Type II alone.
[0052] TABLE 8 shows linearity measurements for Photographic Sample 101 relative to prior
art Sample 102. Non-linearity is measured as the speed separation between the contrasts
of the two blue layers of differing sensitivities. The juncture where the less sensitive
layer becomes the dominant layer in contrast is determined for each photographic coating.
The speed separation between the contrasts of the two blue layers is determined at
this point and indicates non-linearity when non-zero values result. Non-linearities
cause difficulty for printer algorithms as well as adversely affecting the color reproduction.
TABLE 8
Image Coupler Levels (g/sq m) by Layer |
Blue Layer Non-Linearity |
Photographic Sample Number |
Most Sensitive Y-1/Y-2 |
Least Sensitive Y-1/Y-2 |
|
|
0.215/0.000 |
0.753/0.000 |
0.03 |
102(C) |
0.089/0.226 |
0.280/0.700 |
0.00 |
101(Inv) |
[0053] The two formulations show the advantage in linearity for a combination of Type I
and II couplers relative to Type II alone.
[0054] TABLE 9 shows the photographic responses associated with Photographic Sample 103
of the invention relative to two examples of the prior art (Photographic Samples 104
and 105). Each formulation is given a white light exposure, and the modulated transfer
function (MTF) at 2.5 cycles/mm is measured. The measure correlates with light scatter
or sharpness. Red element response is employed as the element which is farthest removed
from the light source, and, therefore, the layer most affected by light scatter by
overlying elements.
TABLE 9
Image Coupler Levels (g/sq m) by Layer |
Blue Layer Non-Linearity |
Sharpness (MTF) Red |
Photographic Sample Number |
Most Sensitive 1/Y-2 or Y-3 |
Least Sensitive Y-1/Y-2 or Y-3 |
|
|
|
0/0.268 0/Y-2 |
0/0.913 0/Y-2 |
0.03 |
105 |
104(C) |
0.063/0.253 Y-1/Y-3 |
0.215/0.859 Y-1/Y-3 |
0.00 |
101 |
105(C) |
0.063/0.196 Y-1/Y-2 |
0.215/0.666 Y-1/Y-2 |
0.00 |
105 |
103(Inv) |
[0055] Two of the three formulations shown in TABLE 9 have approximately the same coated
coupler laydown and show similar effects on the underlying red sharpness measure.
The third formulation, a Type I coupler with a Type II coupling-off group in combination
with a Type II coupler, however, requires a greater laydown with its accompanying
layer thickness increase and light scattering characteristics. This is evidenced in
the lower sharpness values for Photographic Sample 105 relative to the other two samples.
Thus, the combination of the invention provides the advantage of improved sharpness
without undue increase in coating weight and the disadvantages that such an increase
entails.