Note: Descriptions are shown in the official language in which they were submitted.
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INTERNALLY DOPED SURFACE SENSITIZED HIGH CHLORIDE
SILVER HALIDE EMULSIONS AND PHOTOGRAPHIC ELEMENTS AND
PROCESSES FOR THRIR PREPARATION
Field of the Invention
This invention is directed to improved photo-
graphic elements of the developing out type, to high
chloride silver halide emulsions and to methods of preparing
such emulsions.
Summary of the Invention and State-o~-the-Art
The overwhelming ma~ority of radiation-sensitive
silver halide emulsions and photographic elements are light-
sensitive, and of the developing out type. That is, the
emulsions and elements are rendered developable in areas
where imagewise exposure to light occurs and are contacted
with a developer solution to produce a visible image.
Silver bromide and silver bromoiodide emulsions have been
preferentially used for higher speed imaging applications.
As compared with silver bromide and silver bromo-
iodide, high chloride silver halide emulsions and photo-
graphic elements o~ the developing out type offer distinct
advantages in a number of respects. For example, silver
chloride possesses less native sensitivity in the visible
region of the spectrum than silver bromide, thereby per-
mitting yellow filter layers to be omitted from multicolorphotographic elements. Further, high chloride silver
halides are more soluble than silver bromide and silver
bromoiodide, thereby permitting development to be achieved
in shorter times. Unfortunately these advantages of high
chloride silver halides have frequently not been realized in
higher speed imaging applications, since the relatively
higher speeds of silver bromide and silver bromoiodide have
dictated their use.
This invention satisfies a long standing need in
the art in providing high chloride silver halide emulsions
and photographic elements of the developing out type of
increased photographic speed. It has been discovered that
the speed of high chloride silver halide emulsions and
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photographic elements of the developing out type can be
unexpectedly increased by doping silver halide grains which
are at least 80 mole percent silver chloride~ based on total
silver halide, with very low concentrations of divalent
metals. This discovery is surprising not only because of
the increased photographic speeds obtained, but also because
extensive prior investigations of divalent metal dopants for
silver halide grains by those skilled in the art have failed
to identify these advantageous emulsions and photographic
elements and have impliedly and, in some instances, expli-
citly taught away from this discovery.
The recognized utility for incorporating di-
valent metals in silver chloride containing photographic
elements has been largely directed to comparatively special-
ized, nondeveloping out applications using substantiallyhigher concentrations of the divalent metals than herein
employed. For example~ the most extensive use of divalent
metal dopants in negative-working silver chloride emulsions
has occurred in printout and direct-print photographic
elements. Printout photographic elements produce a negative
visible image directly upon imagewise exposure without the
use of a developer. Direct-print emulsions employ a high
intensity imagewise exposure followed by uniform exposure to
lower intensity light--e.g., ambient lighting--to provide a
visible negative image. Illustrative patents disclosing
divalent metal doped silver chloride emulsions useful in
printout and direct-print photographic elements as well as
divalent metal concentrations are set forth below in Table I.
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Table I
Divalent Conc.
U.S. Patent Metal (Mo~e ~)
.
3,033,682 (Hunt~ Pb 0.1 - 25
3,047,392 (Scott) Cd 0.65 - 25
Pb 0.35 - 6.9
3,287,136 (Mc~ride) Pb 0.01 - 1
3,615,61~ (Krohn et al~ Cu 0.03 - 15
Pb 0.07 - 50
3,66~,100 (Hee~s et al) Pb 0.05 - 15
In still a more specialized application ~laase et al U.S.
Patent 3,709,692 teaches to use large monocrystals of ;
silver chloride as radiation particle track detectors.
The silver chloride monocrystals contain 3.5 X 10 4 to
7 X 10 3 mole percent lead and 2.5 X 10 3 to 1.4 mole per-
cent cadmium. The monocrystals are flashed with high
intensity light to produce a visible track.
It has been reported and demonstrated that the
use of divalent metal ions in negative-working silver
halide emulsions of the developing out type has the effect
of decreasing the sensitivity of the emulsions to ambient
light. Mueller et al U.S. Patent 2,950,972 teaches to
incorporate cadmium ions in silver bromide and silver ;
bromoiodide emulsions in concentrations of at least 1 X
10 3 mole percent for the purpose of increasing X-ray and -
gamma sensitivity of the emulsion. Mueller et al teaches
that these small amounts of cadmium have the effect of
producing a marked decrease in the sensitivity of the emul-
sions to visible light. This effect is demonstrated with
3 a 30 mole percent bromide silver bromochloroiodide emul-
sion by Iwaosa et al U~S. Patent 3,901,711. In Example 2 .
a silver bromochloroiodide emulsion containing 30 mole per-
cent bromide and a slight amount of silver iodide is
treated with strontium chloride as a metal dopant and
various combinations of gold chloride and polyethylene
glycol. The effect of the strontium chloride is to reduce
the sensitivity of low intensity exposures of emulsions
I and J as compared respectively with otherwise similar
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emulsions G and H. Iwaosa et al teaches the use of cad-
mium, zinc or lead compounds in combination with gold
salts and polyalkylene oxides in order to avoid undesirable
high intensity reciprocity failure. Assuming lead chloride
to be employed as a divalent metal salt, this requires a
minimum of 3.6 X 10 3 mole percent lead to be present in
the emulsion. Cadmium and zinc, being of lower molecular
weight, would be present in even higher molar concentra-
tions.
Halwig U.K. Patent 1,121,496 teaches to obtain
higher printing speeds and wider exposure latitudes for
silver chlorobromide emulsions containing at least 50 mole
percent chloride by incorporating at least 0.1 gram of di-
valent cadmium per mole of silver halide (i.e., 8.9 X 10 2
mole percent cadmium per mole of silver halide). Halwig
avoids the lower divalent metal ion concentration levels
taught by Mueller et al and demonstrated by Iwaosa et al to
desensitize silver bromide, silver bromoiodide and 30 mole
percent silver bromide silver bromochloroiodide emulsions.
In one aspect this invention is directed to a
silver halide emulsion of the developing out type comprised
of sensitized silver halide grains which are at least 80
mole percent silver chloride and less than 5 mole percent
silver iodide, based on total silver halide. The silver
halide grains are internally doped with cadmium, lead,
copper, zinc or mixtures thereof in a speed increasing
amount of up to 7 X 10 5 mole per mole of silver halide.
In another aspect this invention is directed to a
photographic element of the developing out type comprised of
a support and, coated on the support, a silver halide emul-
sion layer comprised of an emulsion as described above.
In an additional aspect this invention is directed
to a process of forming a silver halide emulsion of the
developing out type by reacting a water soluble silver salt
with one or more water soluble halide salts in an aqueous
medium containing a peptizer to form radiation-sensitive
silver halide grains and surface chemically sensitizing the
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silver halide grains with a gold sensitizer. This process
is characterized by the improvement comprising forming
silver halide grains which are at least 80 mole percent
silver chloride and less than 5 mole percent silver iodide,
based on total silver halide, and introducing into the
aqueous medium during formation of the silver halide grains
cadmium, lead, copper, zinc or mixtures thereof, in a total
concentration of from 2 X 10-6 to 7 X 10-5 mole per mole of
silver halide.
It has been discovered quite surprisingly that the
high chloride silver halide emulsions and photographic
elements containing low concentrations of divalent metal ion
dopants as described above exhibit increased photographic
speeds. Thus, such emulsions and photographic elements
15 offer the art recognized advantages attributable to high
chloride silver halide emulsions while achieving photo-
graphic speeds more commonly associated with silver bromide
and silver bromoiodide photographic emulsions. The fact
that the inclusion of low concentrations of divalent metal
20 ions of the type identified above can increase photographic
speeds of these emulsions and photographic elements is, of
course, surprising in view of the teachings in the art that
low concentration levels of divalent metal ion dopants
have the effect of desensitizing silver halide emulsions of
25 higher bromide concentration to visible light. By contrast,
the sensitivity advantages of the emulsions and photographic
elements of this invention can be realized under the
exposure conditions of candid photography (that is, includ-
ing low intensity and available light exposure conditions).
3 Finally, the present improvement in sensitivity has been
surprisingly demonstrated to be a function of the halide
content of the silver halide grains. Specifically, it has
been observed that the improvement in sensitivity is
highest for silver chloride, silver chlorobromides of at
35 least 80 mole percent chloride, based on total silver
halide, and silver chloroiodides of less than 5 mole per-
cent iodide, based on total silver halide, and that compar-
able speed improvements have not been realized with silver -~
halide gralns of higher silver bromide or iodide content.
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The advantages and features of the present
invention can be better appreciated by reference to the
following detailed description directed to certain pre-
ferred embodiments considered in conjunction with the
drawings, in which
Figure 1 is a plot of dopant level in mg per
mole of silver versus relative speed and
Figures 2 and 3 are plots of percent increase in
relative speed versus mole percent silver bromide and
10 silver iodide, respectively.
The silver halide emulsions of the present inven-
tion are comprised of silver halide grains which are at
least 80 mole percent silver chloride and less than 5 mole
15 percent silver iodide, based on total silver halide. In one
preferred form the silver halide grains consist essentially
of silver chloride. Because the solubility product constant
of silver chloride is orders of magnitude ~igher than that
of silver bromide or silver iodide, it is recognized that
20 formation, ripening or extended holding of silver chloride
grains in the presence of bromide and/or iodide ions will
result in the inclusion of silver bromide and/or silver
iodide in the silver chloride grains. The preferred silver
halide grains are those which are at least 30 mole percent
silver chloride. The remaining silver halide, if 'any,
present in the silver halide grains can be silver bromide,
silver iodide or some combination of the two. Silver bromide
can be present in concentrations of up to 20 mole percent,
preferably up to 15 mole percent, based on total silver halide.
3 Silver iodide can be present in concentrations of less than
5 mole percent, preferably less than 2 mole percent, based on
total silver halide. These silver halide grains are herein
referred to as high chloride silver halide grains.
The high chloride silver halide grains contain
a speed increasing amount of a metal dopant. The metal
dopant can be cadmium, lead, copper, zinc or a combination
of these elements in any proportion. While the metal
dopants have the effect of increasing the sensitivity of
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sur~ace chemically sensitized high chloride silver halide
grains at concentrations up to and inclucling 7 X 10 5 mole
per mole of silver halide, if the concentration levels are
extended upwardly, the e~fect is to desensitize the emul-
sions. Significant improvements in the sensitivity of sur-
face chemically sensitized emulsions have been observed
when the metal dopants are introduced in concentrations in
the range of from 2 X 10 6 to 7 X 10 5 mole per mole of
silver halide during formation of the high chloride silver
halide grains.
While cadmium, lead, zinc and copper internal
dopants produce qualitatively similar effects in increasing
the speed of surface chemically sensitized high chloride to
silver halide emulsions, these elements differ in the de-
gree to which they are capable of sensitizing the emulsions.Cadmium produces emulsions of the highest attainable sensi-
tivities followed in effectiveness by zinc, lead and copper
in that order. To form emulsions of the highest attainable
sensitivities it is preferred to employ cadmium, zinc or
combinations of these elements in concentrations of from
3 X 10-6 to 6 X 10-5, optimally 5 X 10-6 to 2.5 X 10-5,
mole per mole of silver halide during formation of the
high chloride silver halide grains. For emulsions of the
highest attainable sensitivities using lead, copper or
combinations of these elements as dopants, it is preferred
to provide concentrations in the range of from 3 X 10 6 to
5 X 10 5, optimally from 8 X 10-6 to 2 X 10-5, mole per mole
of silver halide during formation of the high chloride sil-
ver halide grains.
3 Radiation-sensitive silver halide emulsions are
conventionally formed by reacting a water soluble silver
salt with one or more water soluble halide salts in an
aqueous medium containing a peptizer. The choice and pro-
portion of halide salts controls the halide content of the
silver halide grains formed. The peptizer maintains the
silver halide grains in dispersion. Where a metal dopant
is intended to be introduced into the silver halide grains,
it can be introduced in any convenient manner~ typically
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separately or with one of the sllver or halide salts or the
peptizer, in the form of a salt which is water soluble in
its contemplated concentration ranges. By regulating the
compositions and rates of addit:Lon of halide and divalent
metal salts, emulsions containing the internally doped high
chloride silver halide grains described above can be pro-
duced by otherwise conventional techniques~ such as the
double and single jet precipitation techniques described by
Mueller et al U.S. Patent 2,950,972, Iwaosa et al U.S.
Patent 3,901l711 and Halwig U.~ Patent 1,121,496.
In one preferred embodiment emulsions containing
the internally doped high chloride silver halide grains
described above are formed by a double Jet precipitation
technique using accelerated flow rates to produce rela-
tively monodispersed, cubic grains. As employed herein,
the term "monodispersed" indicates that at least 95 per-
cent, by weight or by number, of the silver halide grains
are within 40 percent of their mean effective diameter.
In a specifically preferred form at least 95 percent, by
weight or by number, of the silver halide grains are within
25 percent of the mean effective diameter, optimally within
10 percent of the mean effective diameter. The term
"effective diameter" is herein employed as the diameter of
the circle corresponding in area to the area subtended by
a silver halide grain as viewed through a microscope or in
a photomicrograph. The measurement of silver halide grain
sizes is discussed further in Mees and James, The Theory of
the Photograhlc Process, 3rd Ed.g Macmillan, 1966, pp. 36-43.
In double jet precipitations a silver salt, such
as silver nitrate, and a chloride salt, optionally employed
in combination with a bromide and/or iodide salt, such as
one or more chloride or other halide salts of an alkali or
alkaline earth metal te.g., sodium, potassium, magnesium or
calcium), each in the form of an aqueous salt solution, are
concurrently and separately introduced into the reaction
vessel. An aqueous dispersing medium is present in the
reaction vessel prior to the introduction of the aqueous
. . . - ..
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halide and silver salt solutions. The presence of the
dispersing medium along with agitation, in most instances,
facilitates uniform blending of the aqueous halide and
silver salt solutions while avoiding localized concentration
gradients. Typically a dispersing medium volume is ini-
tially present in the reaction vessel which is from about 10
to 90 percent, preferably 20 to 80 percent, that of the
silver halide emulsion to be formed. The dispersing medium
is conventionally water or a dispersion of peptizer in
water, optionally containing other ingredients, such as one
or more silver halide ripening agents, more specifically
described below. Preferably peptizer in a concentration of
at least 10 percent, most preferably 20 percent, of the
total weight of the vehicle present in the finished emulsion
is initially present in the dispersing medium within the
reaction vessel. Where the peptizer is not initially entire-
ly present in the dispersing medium, the balance of the
peptizer is preferably added during addition of the silver
and halide salts. A minor portion of one of the silver or
halide salt solutions, typically less than about 10 percent,
is also initially present in the reaction vessel to adjust
the pAg (log reciprocal silver ion concentration) of the
reaction vessel contents at the outset of silver halide
precipitation.
During the initial introduction of the aqueous
silver and halide salt solutions into the reaction vessel
the dissolved silver salt reacts with dissolved halide
salt to form silver halide crystals. This initial phase of
silver halide emulsion formation in which new silver halide
3 crystals are being formed is referred to as nucleation.
During subsequent addition of silver and halide salts,
additional silver halide formed as a reaction product can
be precipitated onto these nuclei, causing the mean size
of the silver halide to increase and ultimately resulting
in silver halide grains of the desired mean effective
diameter.
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Although additional silver halide grain formation
can occur after the initial formation of silver halide
nuclei, by controlling the rate of addition of silver and
halide salts continued silver halide precipitation onto the
originally formed silver halide nuclei can be achieved.
This has the effect of producing a population of silver
halide grains of similar size--i.e., monodispersed silver
halide emulsions. Techniques are known in the art which
achieve shortened silver halide precipitation times by per-
mitting accelerated rates of addition of silver and halidesalts. Such techniques are disclosed, for example, by
Wilgus German OLS 2,107,118 and Kurz U.S. Patent 3,672,900.
Single ~et silver halide grain precipitation is
specifically contemplated as an alternative to double jet
precipitation. In single ~et precipitation substantially
- the entire halide salt solution is present in the reaction
vessel prior to introduction of the silve~ salt solution.
The silver halide grains which are formed are polydispersed--
this is, they vary significantly in size and do not satis~y
the grain si~.e distribution requirements set forth above for
monodispersed silver halide emulsions. Except for these
differences the preferred aspects of double ~et silver halide
precipitation techniques described above are also applicable
! 25 to single jet precipitation techniques.
In both the singlie jet and double ~et precipitation
techniques the divalent metal salts, typically metal halides
(e.g., cadmium, lead, copper and zinc chlorides), can be
introduced into the reaction vessel at any time before
introduction of at least 85 percent, most preferably 75
percent, of the silver salt solution has been completed.
The divalent metal salts are preferably dissolved in water
or other suitable solvent prior to addition to the reaction
vessel. The solution containing the divalent metal salt
typically comprises from about 1 to 10 percent by weight of
the dispersing medium of the emulsion, the proportions be-
ing merely a matter of choice and convenience.
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The individual reactants can be added to the
reaction vessel through surface or sub-surface delivery
tubes by gravity feed or by delivery apparatus for main-
taining control of the rate of delivery and the pH and/or
pAg of the reaction vessel contents, as illustrated by
Culhane et al U.S. Patent 3,821,002, Oliver U.S. Patent
3,031,304 and Claes et al, Photo~raphische Korrespondenz,
102 Band, Number 10, 1967, p. 162. In order to obtain
rapid distribution of the reactants within the reaction
vessel, specially contructed mixing devices can be
employed, as illustrated by Audran U.S. Patent 2,996,287,
McCrossen et al U.S. Patent 3,342,605, Frame et al U.S.
Patent 3,415,650, Porter et al U.S. Patent 3,785,777,
Saito et al German OLS 2,556,~85 and Saito et al German
OLS 2,555,364. An enclosed reaction vessel can be employed
to receive and mix reactants upstream of the main reaction
vessel, as illustrated by Forster et al U.S. Patent
3,897,935 and Posse et al U.S. Patent 3,790,386.
The initially formed silver halide grains (i.e.,
silver halide nuclei~ are sufficiently small that they can
be dispersed by water alone. Thus, it is unnecessary to
have any peptizer initially in the reaction vessel, al-
though it is frequently convenient to have the peptizer at
least partially present in the reaction vessel prior to
initiating introduction of the silver and halide salts.
Peptizer can be added to the reaction vessel with the
halide salt, the silver salt or both and/or independently
of both. While peptizer concentrations from 0.2 to about
10 percent by weight, based on the total liquid or emul-
3 sion weight in the reaction vessel, can be employed, it ispreferred to keep the concentration of the peptizer in
the reaction vessel prior to and during silver halide
formation below about 6 percent by weight, based on the
total weight. It is common practice to maintain the
concentration of the peptizer in the reaction vessel in
the range of from about 2 to 6 percent, based on the total
weight, prior to and during silver halide formation and to
adjust the emulsion vehicle concentration upwardly for
llXO~i;S
optimum coating characteristics by delayed, supplemental
vehicle additions. It is contemplated that the emulsion
as initially formed will contain ~rom about 5 to 50 grams
of peptizer per mole of silver halide, pre~erably about
5 10 to 30 grams of peptizer per mole of silver halide.
Additional vehicle can be added later to bring the con-
centration up to as high as 300 grams per mole of silver
halide. Preferably the concentration of vehicle in the
finished emulsion is below 50 grams per mole of silver
10 halide. When coated and dried in forming a photographic J
element the vehicle preferably forms about 30 to 70 percent
by weight of the emulsion layer.
Vehicles (which include both binders and peptizers)
can be chosen from among those conventionally employed in
15 silver halide emulsions. Preferred peptizers are hydro-
philic colloids, which can be employed alone or in combina-
tion with hydrophobic materials. Suitable hydrophilic
materials include both naturally occurrin~ substances such
as proteins, protein derivatives, cellulose derivatives--
20 e.g., cellulose esters, gelatin--e.g., alkali-treated gelatin
(cattle bone or hide gelatin) or acid-treated gelatin
(pigskin gelatin), gelatin derivatives--e.g., acetylated
gelatin, phthalated gelatin and the like, polysaccharides
such as dextran, gum arabic, zein, casein, pectin, collagen
25 derivatives, collodion, agar-agar, arrowroot, alb'umin and
the like as described in Yutzy et al U.S. Patents 2,614,928
and '929, Lowe et al U.S. Patents 2,691,582, 2,614,930,
'931, 2,327,808 and 2,448,534, Gates et al U.S. Patents
2,787,545 and 2,956,880, Himmelmann et al U.S. Patent
3 3,061,436, Farrell et al U.S. Patent 2,816,027, Ryan U.S.
Patents 3,132,945, 3,138,461 and 3,186,846, Dersch et al
U.K. Patent 1,167,159 and U.S. Patents 2,960,405 and 3~436,220,
Geary U.S. Patent 3,486,896, Gazzard U.K. Patent 793,549,
Gates et al U.S. Patents 2,992,213, 3,157,506, 3,184,312 and
35 3,539,353, Miller et al U.S. Patent 3,227,571, Boyer et al
U.S. Patent 3,532,50 2, Malan U.S. Patent 3,551,151, Lohmer
et al U.S. Patent 4,018,609, Luciani et al U.K. Patent
1,186,790, U.K. Patent 1,489,080 and Hori et al Belgian
,: :
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7~5
- 13 -
Patent 856,631, U.K. Patent 1,490,644, U.K. Patent
1,483,551, Arase et al U.K. Patent 1,459,906, Salo U.S.
Patents 2,110,491 and 2,311,086, Fallesen U.S. Patent
2,343,650, Yutzy U.S. Patent 2,322,085, Lowe U.S. Patent
2,563,791, Talbot et al U.S. Patent 2,725,293, Hilborn U.S.
Patent 2,748,022, DePauw et al U.S. Patent 2,956,883, Ritchie
U.K. Patent 2,095, DeStubner U.S. Patent 1, 752, o69,
Sheppard et al U.S. Patent 2,127,573, Lierg U.S. Patent
2,256,720, Gaspar U.S. Patent 2,361,936, Farmer U.K.
Patent 15,727, Stevens U.K. Patent 1,062,116 and Yamamoto
et al U.S. Patent 3,923,517.
Other materials commonly employed in combination
with hydrophilic colloid peptizers as vehicles including
vehicle extenders--e.g., materials in the form of latices)
15 include synthetic polymeric peptizers, carriers and/or
binders such as poly(vinyl lactams), acrylamide polymers,
polyvinyl alcohol and its derivatives, polyvinyl acetals,
polymers of alkyl and sulfoalkyl acrylates and methacrylates,
hydrolyzed polyvinyl acetates, polyamides, polyvinyl pyri-
20 dine, acrylic acid polymers, maleic anhydride copolymers,polyalkylene oxides, methacrylamide copolymers, polyvinyl
oxazolidinones, maleic acid copolymers, vinylamine copoly-
mers, methacrylic acid copolymers, acryloyloxyalkylsulfonic
acid copolymers, sulfoalkylacrylamide copolymers, poly- .
25 alkyleneimine copolymers, polyamines, N,N-dialkylamino-
alkyl acrylates, vinyl imidazole copolymers, vinyl sulfide :
copolymers, halogenated styrene polymers, amineacrylamide
polymers, polypeptides and the like as described in Hollist-
er et al U.S. Patents 3,679,425, 3,706,564 and 3,813,251,
3 Lowe U.S. Patents 2,253,078, 2,276,322, l323, 2,281,703,
2,311,058 and 2,414,207, Lowe et al U.S. Patents 2,484,456
2,541,474 and 2,632,704, Perry et al U.S. Patent 3,425,836,
Smith et al U.S. Patents 3,415,653 and 3,615,624, Smith
U.S. Patent 3,488,708, Whiteley et al U.S. Patents :
35 3,392,025 and 3,511,818, Fitzgerald U.S. Patents 3,681,079,
3,721,565, 3,852,073, 3,861,918 and 3,925,083, Fitzgerald
et al U.S. Patent 3,879,205, Nottorf U.S. Patent 3,142,568,
Houck et al U.S. Patents 3,062,674 and 3,220,844, Dann et
.
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-14-
al U.S. Patent 2,882,161, Schupp U.S. Patent 2,579,016,
Weaver U.S. Patent 2,829,053, Alles et al U.S. Patent
2,698,240, Priest et al U.S. Patent 3,oo3,879, Merrill et
al U.S. Patent 3,419,397, Stonham U.S. Patent 3,284,207,
Lohmer et al U.S. Patent 3,167,430, Williams U.S. Patent
2,957,767, Dawson et al U.S. Patent 2,893,867, Smith et al 3
U.S. Patents 2,860,986 and 2,904,539, Ponticello et al U.S.
Patents 3,929,482 and 3,860,428, Ponticello U.S. Patent
3,939,130, Dykstra U.S. Patent 3,411,911 and Dykstra et al
10 Canadian Patent 774,054, Ream et al U.S. Patent 3,287,289,
Smith U.K. Patent 1, 466,600, Stevens U.K. Patent 1,0 62,116,
Fordyce U.S. Patent 2,211,323, Martinez U.S. Patent
2,284,877, Watkins U.S. Patent 2,420,455, Jones U.S. Patent
2,533,166, Bolton U.S. Patent 2,495,918, Graves U.S. Patent
15 2,289,775, Yackel U.S. Patent 2,565,418, Unruh et al U.S.
Patents 2,865,893 and 2,875,059, Rees et al U.S. Patent
3,536,491, Broadhead et al U.K. Patent 1,348,815, Taylor et
al U.S. Patent 3,479,186, Merrill et al U.S. Patent
3,520,857, Bacon et al U.S. Patent 3,690,888, Bowman U.S.
20 Patent 3,748,143, Dickinson et al U.K. Patents 808,227 and
'228, Wood U.K. Patent 822,192 and Iguchi et al U.K.
Patent 1,398,055. These additional materials need not be
present in the reaction vessel during silver halide pre-
cipitation, but rather are conventionally added to the
25 emulsion prior to coating. The vehicle materials, includ-
ing particularly the hydrophilic colloids, as well as the
hydrophobic materials useful in combination therewith can
be employed not only in the emulsion layers of the photo-
graphic elements of this invention, but also in other
3 layers, such as overcoat layers, interlayers and layers
positioned beneath the emulsion layers.
Although not required for the practice of this
process, it is preferred that a silver halide ripening
agent be present within the reaction vessel during silver
halide formation. The ripening agent can be entirely
contained within the dispersing medium in the reaction
vessel before silver and halide salt addition, or it can be
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introduced into the reaction vessel along with one or more
of the halide salt, silver salt or peptizer. In still
another variant the ripening agent can be introduced
independently during halide and silver salt additions.
Sulfur containing ripening agents are generally
preferred. Conventional thioether ripening agents, such
as those disclosed in McBride U.S. Patent 3,271,157,
can be employed. Sufficient
thioether ripening agent is employed to provide concen-
trations of from 0.0~ to 50 grams, preferably ab~ut 0.1 to
20 grams, per mole o~ silver h~lide, based on the weight
of silver.
Certain of the preferred organic thioether
silver halide solvents can be represented by the formulas:
2)r CH2-5- tCH2) 2-X- (R) - (CH )
(R' )q~S~CH2(CH2)m Z]n
and
Q (CH2)m (CH2 S-~H2)n-S-CH2(CH2)r_Z
wherein: r and m are integers of 0 to 4; n is an integer
of 1 to 4; p and q are integers of 0 to 3; X is an oxygen
atom (-O-), a sulfur atom (-S-),
o
a carbamyl radical ( -CNH- ),
o5 a carbonyl radical (-C-) or
O
a carboxy radical (-COH);
R and R' are ethylene oxide radicals (-O-CH2CH2-); Q and
~ are hydroxy radicals (-OH), carboxy radicals, or alkoxy
3 radicals (~O-alkyl) wherein the alkyl group has 1 to 5
carbon atoms; and Q and Z can also be substituents des-
cribed for X linked to form a cyclic compound.
Preferred organic thioether silver halide
ripening agents suitable for forming the emulsions of
the invention include compounds represented by the
formulas:
- : :
-
.. ,, . , ; , ~ . : :
,. .. : ~
7~5
-16-
HO(-R2-S-)rR OH,
-R2-S-R2-o-R4 )
O
R3-o-R2-s_R2_cNH_R4_~2,
(R3_o_R2-S-R2-)2S,
( R3-NHC-R2-S-R2- ) 2 and
~ ( R - 0) s~R~\
(R - 0) s - R2/
wherein r is an integer of l to 3; s is an integer o~ l
to 2; R is an alkylene radical having l to 5 carbon atoms
and is preferably ethylene (-CH~CH2-); R3 is an alkyl
15 radical having l to 5 carbon atoms and is preferably
ethyl; and R is an alkylene radical having l to 5 carbon
- atoms and is preferably methylene (-CH2-).
As an alternative to thioether ripening agents,
thiocyanate salts can be used, such as alkali metal, most
commonly potassium, and ammonium thiocyanate salts. While
any conventional quantity of the thiocyanate salts can be
introduced, preferred concentrations are generally from
about 0.1 to 20 grams of thiocyanate salt per mole of
silver halide, based on the weight of silver. Illustrative
25 pri~r teachings of employing thiocyanate ripening~agents
are found in Nietz and Russell, U.S. Patent 2,222,264, -
cited above; Lowe et al U.S. Patent 2,448,534, issued
September 7, 1948; and Illingsworth U.S. Patent 3,320,069,
issued May 16, 1967.
The emulsion containing high chloride silver
halide grains is preferably washed or otherwise processed
to remove soluble salts. The soluble salts can be removed
by chill setting and leaching, as illustrated by Cra~t U.S.
35 Patent 2,316,845 and McFall et al U.S. Patent 3,396,~27; by
coagulation washing, as illustrated by Hewitson et al U.S.
Patent 2,618,556, Yutzy et al U.S. Patent 2,614,S28, Yackel U.S.
Patent 2,565,4:18, Hart et al U.S. Patent 3,241,969, Waller
- ~ ~ , ,.................. ,
~, ., - . . , : :
,
:. : :.: - -. :. : :
7 6
-17-
et al U.S. Patent 2~48g~341~ Klinger U.K. Patent 1,305,409
and Dersch et al U.K. Patent 1,167,159; by centrifugation
and decantation of a coagulated emulsion, as illustrated
by Murray U.S. Patent 2,463,794, U~ihara et al U.S. Patent
3,707,378, Audran U.S. Patent 2,996,287 and Timson U.S.
Patent 3,498,454; by employing hydrocyclones alone or in
combination with centrifuges, as illustrated by U.K.
Patent 1,336,692, Claes U.K. Patent 1,356,573 and Ushomir-
skii et al Soviet Chemical Industry, Vol. 6, No. 3, 1974,
10 pp. 181-185; by diafiltration with a semipermeable mem-
brane, as illustrated by Research Disclosure, Vol. 102,
October 1972, Item 10208, Hagemaier et al Research Dis-
closure, Vol. 131, March 1975, Item 13122, Bonnet Research
Disclosure, Vol. 135, July 1975, Item 13577, Berg et al
15 German OLS 2,436,461 and Bolton U.S. Patent 2,495,918 or
by employing an ion exchange resin, as illustrated by
Maley U.S. Patent 3,782,953 and Noble U.S. Patent 2,827,428.
The emulsions, with or without sensitizers, can be dried
and stored prior to use as illustrated by Research Dis-
20 closure, ~ol. 101, September 1972, Item 10152.
In order to achieve the full improvement in sen-
sitivity of this invention it is preferred that the inter-
nally doped high chloride silver halide grains be surface
chemically sensitized. The high chloride silver halide
grains can bé surface chemically sensitized with active
gelatin, as illustrated by T. H. James, The Theory of the
Photographic Process, 4th Ed., Macmillan, 1977, pp. 67-76,
or with sulfur, selenium5 tellurium, platinum, palladium,
iridium, osmium, rhenium or phosphorus sensitizers or
3 combinations of these sensitizers, such as at pAg levels of
from 5 to 10, pH levels of from 5 to 8 and temperatures o~
from 30 to 80C, as illustrated by Research Disclosure, Vol.
120, April 1974, Item 12008, Research Disclosure, Vol. 134,
June 1975, Item 13452, Sheppard et al U.S. Patent 1,623,499,
Waller et al U.S. Patent 2~399,083, Damschroder et al U.S.
Patent 2,642,361, McVeigh U.S. Patent 3,297,447, Dunn U.S.
Patent 3,297,446, McBride U.K. Patent 1,315,755, Berry et al
U.S. Patent 3,772,031, Gilman et al U.S. Patent 3,761,267, Ohi
. .
,`,, ' "' ' ' ' i' ' ' ~'''' '' ~ `' :
, '~' " "' ,, ' '": ''' ' ~.
765
-18-
; et al U.S. Patent 3,857,711, Klinger et al U.S. Patent
3,565,633 and Oftedahl U.S. Patents 3,901,714 and 3,904,415.
The emulsions can also be reduction sensitized--e.g., with
hydrogen, as illustrated by Janusonis U.S. Patent 3,891,446
and Babcock et al U.S. Patent 3,984,249, by low pAg ~e.g.,
less than 5) high pH ~e.g., greater than 8~ treatment or
through the use of reducing agents, such as stannous
chloride, thiourea dioxide, polyamines and amineboranes,
as illustrated by Allen et al U.S. Patent 2,983,609,
Oftedahl et al Research Disclosure, Vol. 136, August 1975,
Item 13654, Lowe et al U.S. Patents 2,518,698 and 2,743,182,
Chambers et al U.S. Patent 3,026,203 and Bigelow et al
- U.S. Patent 3,361,564.
In a preferred form the internally doped high
chloride silver halide grains are surface chemically sensi-
^ tized with gold sensitizers employed alone or in combination
with other conventional chemical sensitizers. The internally
doped high chloride silver halide grains can be surface
gold sensitized with one or a combination of con~entional
20 gold sensitizers. Illustrative gold sensitizers include
gold hydroxide, gold chloride, potassium aurate, potassium
auriaurite, potassium auricyanide, potassium aurithiocyanate,
- gold sulfide, gold selenide, gold silver sulfide~ gold iodide,
potassium chloroaurate, ethylenediamine-bis-gold chloride
~ 25 and.various organic gold sensitizers, as more fully des-
; cribed by Damschroder et al U.S. Patent 2,642,361 and
McVeigh U.S. Patent 3,297,447.
..
Depending upon the photographic application,
. 3 emulsions containing the high chloride silver halide grains
can contain other components of a conventional nature. For
example3 it is specifically contemplated to blend the high
chloride silver halide emulsions described above with other
silver halide emulsions. Blending of silver halide emulsions
is commonly undertaken to optimize characteristic curve
. shapes--e.g., adjust contrast, extend exposure latitudeg
increase maximum density and to achieve other, similar
`~ curve modifications. Blends of surface~sensitive emulsions
. . .
:, .
'
' ' . ' '
- , : : . : ,
.. ,, : : ~
~lZ~7~5
and internally fogged, internal image-forming emulsions can
be employed, as illustrated by Luckey et al U.S. Patents
2,996,382, 3,397,987 and 3,705,858, Luckey U.S~ Patent
3,694,881, Research Disclosure, Vol. 134, June 1975, Item
13452, Millikan e~ al Defensive Publication T-904017,
April 21, 1972 and Kurz Research Disclosure, Vol. 122,
June 1974, Item 12233. In a specifically preferred form
the maJor portion, preferably essentially all, of the sil-
ver halide grains present in a silver halide emulsion or
silver halide emulsion layer are internally doped high
chloride silver halide grains substantially as described
above.
The silver halide emulsions can be spectrally sen-
sitized with dyes from a variety of classes, including the
polymethine dye class, which includes the cyanines, mero-
cyanines, complex cyanines and merocyanines (i.e., tri-,
tetra- and poly-nuclear cyanines and merocyanines), oxonols,
hemioxonols, styryls, merostyryls and streptocyanines.
The cyanine spectral sensitizing dyes include,
joined by a methine linkage, two basic heterocyclic nuclei,
such as those derived from quinolinium, pyridinium, iso-
quinolinium, 3H-indolium, benz[e]indolium, oxazolium,
thiazolium, selenazolinium, imidazolium, benzoxazolinium,
benzothiazolium, benzoselenazolium, benzimidazolium, naph-
thcxazolium, naphthothiazolium, naphthoselenazolium, thia-
zolinium dihydronaphthothiazolium, pyrylium and imidazo-
pyrazinium quaternary salts.
The merocyanine spectral sensitizing dyes include,
joined by a methine linkage, a basic heterocyclic nucleus
3 of the cyanine dye type and an acidic nucleus, such as can
be derived from barbituric acid, 2-thiobarbituric acid,
rhodanine, hydantoin9 2-thiohydantoin, 4-thiohyantoin, 2-
pyrazolin-5-one, 2-isoxazolin-5-one, indan-1,3-dione,
cyclohexan-1,3-dione, 1,3-dioxan-4,6-dione, pyrazolin-3,5-
dione, pentan-2,4-dione, alkylsulfonyl acetonitrile, malo-
nonitrile, isoquinolin-4-one, and chroman-2,4-dione.
-20-
One or more spectral sensitizing dyes may be
used. Dyes with sensitizing maxima at wavelengths through-
out the visible spectrum and with a great variety of spec-
tral sensitivity curve shapes are known. The choice and
relative proportions of dyes depends upon the region of the
spectrum to which sensitivity is desired and upon the shape
of the spectral sensitivity curve desired. Dyes with
overlapping spectral sensitivity curves will often yield in
combination a curve in which the sensitivity at each wave-
length in the area of overlap is approximately equal to thesum of the sensitivities of the individual dyes. Thus, it
is possible to use combinations of dyes with different
maxima to achieve a spectral sensitivity curve with a
maximum intermediate to the sensitizing maxima of the
individual dyes.
Combinations of spectral sensitizing dyes can be
used which result in supersensitization--that is, spectral
sensitization that is greater in some spectral region than
that from any concentration of one of the dyes alone or
that which would result from the additive effect of the
dyes. Supersensitization can be achieved with selected
combinations of spectral sensitizing dyes and other addenda,
such as stabilizers and antifoggants, development acceler-
ators or inhibitors, coating aids, brighteners and anti-
static agents. Any one of several mechanisms as well ascompounds which can be responsible for supersensitization
are discussed by Gilman, Photographic Science and Engineer-
ng, Vol. 18, 1974, pp. 418-430.
Spectral sensiti~ing dyeQ also affect the emul-
3 sions in other ways. For example, many spectral sensi-
tizing dyes either reduce (desensitize) or increase photo-
graphic speed within the spectral region of inherent sen-
sitivity. Spectral sensitizing dyes can also funGtion as
antifoggants or stabilizers, development accelerators or
inhibitors, reducing or nucleating agents, and halogen
acceptors or electron acceptors, as disclosed in Brooker et
al U.S. Patent 2,131,038, Illingsworth et al U.S. Paten~
3,501,310, We~ster et al U.S. Patent 3,630,749, Spence et
.,, :
- i: ~ " ~ i . -
:
- ~ 5.~7~
-21-
al U.S. Patent 3,718,470 and Shiba et al U.S. Patent
3,930,860.
Sensitizing action can be correlated to the
position o~ molecular energy levels of a dye with respect to
ground state and conduction band energy levels of the silver
halide crystals. These energy levels can in turn be corre-
lated to polarographic oxidation and reduction potentials,
as discussed in Photograæhic Science and Engineering, Vol.
18, 1974, pp. 49-53 (Sturmer et al), pp. 175-178 ~Leubner)
and pp. 475-485 (Gilman~. Oxidation and reduction potentials
can be measured as described by R. J. Cox, Photographic
Sensitivity, Academic Press, 1973, Chapter 15.
The chemistry of cyanine and related dyes is
illustrated by Weissberger and Taylor, Special Topics of
Heterocyclic Chemistry~ John Wiley and Sons, New York,
1977, Chapter VIII; Venkataraman, The Chemistry of ~
thetic Dyes, Academic Press, New York, 1971, Chapter V;
James, The Theory o~ the Photographic Process, 4th Ed.,
Macmillan, 1977, Chapter 8, and F. M. Hamer, Cyanine Dyes
and Related Compounds, John Wiley and Sons, 1964.
Among useful spectral sensitizing dyes for
sensitizing silver halide emulsions are those found in U.K.
Patent 742,112, Brooker U.S. Patents 1,846,300, '301, '302,
'303, '304, 2,078,233 and 2,089,729, Brooker et al U.S.
Patents 2,165,338, 2,213,238, 2,493,747, '748~ 2,526,632,
2,739,964 (Reissue 24,292), 2,778,823, 2,917,516, 3,352,857,
3,411,916 and 3,431,111, Sprague U.S. Patent 2,503,776, Nys
et al U.S. Patent 3,282,933, Riester U.S. Patent 3,660,102,
Kampfer et al U.S. Patent 3,660,103, Taber et al U.S.
3 Patents 3,335,010, 3,352,680 and 3,384,486, Lincoln et al
U.S. Patent 3,397,981, Fumia et al U.S. Patents 3,482,978
and 3,623,881, Spence et al U.S. Patent 3,718,470 and Mee
U.S. Patent 4,025,349. Examples of useful supersensitizing
dye combinations, of non-light absorbing addenda which
function as supersensitizers or of use~ul dye combinations
are found in McFall et al U.S. Patent 2,933,390, Jones et
al U.S. Patent 2,937,089, Motter U.S. Patent 3,506,443 and
Schwan et al U.S. Patent 3,672,898.
.. . . . . .
.. . - . ~
.. ... ..
,:~ . .. , . . :
- .
'7~5
-22-
Instability which increases minimum density in
negative type emulsion coatings ~i.e., fog~ can be protected
against by incorporation o~ stabilizers, anti~oggants,
antikinking agents, latent image stabilizers and similar
addenda in the emulsion and contiguous layers prior to
coating. Most of the antifoggants which are effective in
emulsions can also be used in developers and can be classi-
fied under a few general headings, as illustrated by C.E.K.
Mees, The Theory of the Photographic Process, 2nd Ed.,
Macmillan, 1954, pp. 677-680.
To avoid such instability in emulsion coatings
stabilizers and antifoggants can be employed, such as
halide ions (e.g., bromide salts~; chloropalladates and
chloropalladites, as illustrated by Trivelli et al U.S.
Patent 2,566,263; water-soluble inorganic salts of cadmium,
cobalt, manganese and zinc, as illustrated by Jones U.S.
Patent 2,839,405 and Sidebotham U.S. Patent 3,488,709;
mercury salts, as illustrated by Allen et al U.S. Patent
2,728,663; selenols and diselenides, as illustrated by
Brown et al U.K. Patent 1,336,570 and Pollet et al U.K.
Patent 1,282,303; quaternary ammonium salts of the type
illustrated by A~len et al U.S. Patent 2,694,716, Brooker
et al U.S. Patent 2,131,038, Graham U.S. Patent 3,342,596
and Arai et al U.S. Patent 3,954,478; azomethine desensi-
tizing dyes, as illustrated by Thiers et al U.S. Patent3,630,744; isothiourea derivatives, as illustrated by Herz
et al U.S. Patent 3,220,839 and Knott et al U.S. Patent
2,514,650; thiazolidines, as illustrated by Scavron U.S.
Patent 3,565,625; peptide derivatives, as illustrated by
3 Maffet U.S. Patent 3,274,002; pyrimidines and 3-pyrazoli-
dones, as illustrated by Welsh U.S. Patent 3,161,515 and
Hood et al U.S. Patent 2,751,297; azotriazoles and azo-
tetrazoles, as illustrated by Baldassarri et al U.S. Patent
3,925,086; azaindenes, particularly tetraazaindenes, as
illustrated by Heimbach U.S. Patent 2,444,605, Knott U.S.
Patent 2,933,388, Williams U.S. Patent 3,202,512, Research
Disclosure, Vol. 134, June 1975, Item 13452, and Vol. 148,
.,
. : . .: :
; ~ , . ,~ . ~ .. . . ..
7~5
23-
August 1976, Item 14851, and Nepker et al U.K. Patent
1,338,567; mercaptotetrazoles, -triazoles and -diazoles, as
illustrated by Kendall et al U.S. Patent 2,403,927, Kennard
et al U.S. Patent 3,266,897, Research Disclosure, Vol. 116,
December 1973, Item 11684, Luckey et al U.S. Patent
3,397,987 and Salesin U.S. Patent 3,708,303j azoles, as
illustrated by Peterson et al U.S. Patent 2,271,229 and
Research Disclosure, Item 11684, cited above; purines, as
illustrated by Sheppard et al U.S. Patent 2,319,090, Birr
et al U.S. Patent 2,152,460, Research Disclosure, Item
13452, cited above, and Dostes et al French Patent
2,296,204 and polymers of 1,3-dihydroxy(and/or 1,3-carba-
moxy)-2-methylenepropane, as illustrated by Saleck et al
U.S. Patent 3,926,635.
Among useful stabilizers for gold sensitized
emulsions are water-insoluble gold compounds of benzo-
thiazole, benzoxazole, naphthothiazole and certain mero-
cyanine and cyanine dyes, as illustrated by Yutzy et al
U.S. Patent 2,597,915, and sul~inamides, as illustrated by
20 Nishio et al U.S. Patent 3,498,792.
Among useful stabilizers in layers containing
poly(alkylene oxides) are tetraazaindenes, particularly in
combination with Group VIII noble metals or resorcinol
derivatives, as illustrated by Carroll et al U.S. Patent
25 2,716,062, U.K. Patent 1,466,024 and Habu et al U.S. Patent
3,929,486; quaternary ammonium salts of the type illustrat-
ed by Piper U.S. Patent 2,886,437; water-insoluble hydrox- :~
ides, as illustrated by Ma~fet U.S. Patent 2,953,455; ::
phenols, as illustrated by Smith U.S. Patents 2,955,037 and -
3 '038; ethylene diurea, as illustrated by Dersch U.S. Patent
3,582,346; barbituric acid derivatives, as illustrated by
Wood U.S. Patent 3,617,290; boranes, as illustrated by .
Bigelow U.S. Patent 3,725,078; 3-pyrazolidinones, as illus-
trated by Wood U.K. Patent 1,158,059 and aldoximines,
amidesj anilides and esters, as illustrated by Butler et al
U.K. Patent 988,052. ~;
. . .
. . . . ..
76S
- 24 -
The emulsion layers can be protected from fog and
desensitization caused by contarnination by metals suc~ as
copper, lead, tin, iron and the like, by incorporating
addenda, such as sulfocatechol-type compounds, as illus-
trated by Kennard et al U.S. Patent 3,236,652; aldoximines,
as illustrated by Carroll et al U.K. Patent 623,448 and
meta- and poly-phosphates, as illustrated by Draisbach U.S.
Patent 2,239,284, and carboxylic acids such as ethylene-
diamine tetraacetic acid, as illustrated by U.K. Patent
10 691,715.
Among stabilizers use~ul in layers containing
synthetic polymers of the type employed as vehicles and to
improve covering power are monohydric and polyhydric
phenols, as illustrated by Forsgard U.S. Patent 3,043,697;
15 saccharides, as illustrated by U.K. Patent 897,497 and
Stevens et al U.K. Patent 1,039,471 and quinoline deriva-
tives, as illustrated by Dersch et al U.S. Patent 3,446,618.
Among stabilizers useful in pro~cting the emul-
sion layers against dichroic fog are addenda, such as salts
20 of nitron, as illustrated by Barbier et al U.S. Patents
3,679,424 and 3,820,998; mercaptocarboxylic acids, as
illustrated by Willems et al U.S. Patent 3,600,178, and
addenda listed by E. J. Birr, Stabilization of Photographic
Silver Halide mulsions, Focal Press, London, 1974, pp.
25 126-218.
Among stabilizers useful in protecting emulsion
layers against development fog are addenda such as azabenz-
imidazoles, as illustrated by Bloom et al U.K. Patent
1,356,142 and U.S. Patent 3,575,699, Rogers U.S. Patent
30 3,473,924 and Carlson et al U.S. Patent 3,649,267; substi-
tuted benzimidazoles, benzothiazoles, benzotriazoles andthe like, as illustrated by Brooker et al U.S. Patent
2,131,o38, Land U.S. Patent 2,704,721, Rogers et al U.S.
Patent 3,265,498 ; mercapto-substituted compounds, e.g.,
mercaptotetrazoles, as illustrated by Dimsdale et al U.S.
Patent 2,432,864, Rauch et al U.S. Patent 3,081,170, Weyerts
et al U.S. Patent 3~260,597, Grasshoff et al U.S. Patent
;.'~
;. : . :.
., i , " . ~ : ",., "
' ~
- ~z~
-25-
3,674,478 and Arond U.S. Patent 3,706,557; isothiourea
derivatives, as illustrated by Herz et al U.S. Patent
3,220,839, and thiodiazole derivatives, as illustrated by
von Konig U.S. Patent 3,364,028 and von Konig et al U.K.
Patent 1,186,441.
Where hardeners of the aldehyde type are em-
ployed, the emulsion layers can be protected with anti-
foggants, such as monohydric and polyhydric phenols of the
type illustrated by Sheppard et al U.S. Patent 2,165,421;
nitro-substituted compounds of the type disclosed by Rees
et al U.K. Patent 1,269,268; poly(alkylene oxides), as
illustrated by Valbusa U.K. Patent 1,151,914, and muco-
halogenic acids in combination with urazoles, as illus-
trated by Allen et al U.S. Patents 3,232,761 and 3,232,764,
or further in combination with maleic acid hydrazide, as
illustrated by Rees et al U.S. Patent 3,295,980.
To protect emulsion layers coated on linear
polyester supports addenda can be employed such as para-
banic acid, hydantoin acid hydrazides and urazoles, as
20 illustrated by Anderson et al U.S. Patent 3,287,135, and
piazines containing two symmetrically fused 6-member car-
bocyclic rings, especially in combination with an aldehyde-
type hardening agent, as illustrated in Rees et al U.S.
Patent 3,396,023.
. Kink desensitization of the emulsions can be
reduced by the incorporation of compounds, polymeric latices
and dispersions of the type disclosed by Jones et al U.S.
Patents 2,759,821 and '822; azole and mercaptotetrazole
hydrophilic colloid dispersions of the type disclosed by
3 Research Disclosure, Vol. 116, December 1973, Item 11684; ~;
plasticized gelatin compositions of the type disclosed by
Milton et al U.S. Patent 3,033,680; water-soluble inter-
polymers of the type disclosed by Rees et al U.S. Patent
3,536,491; polymeric latices prepared by emulsion polymeri-
zation in the presence of poly~alkylene oxide~, as disclosed
by Pearson et a:L U.S. Patent 3,772,032, and gelatin graft
copolymers of the type disclosed by Rakoczy U.S. Patent
3,837,861.
~ . .
. . : . :, ., ~ . : :
fi 2~)'765
-26-
Where the photographic element is.to be processed
at elevated ba~h or drying temperatures, as in rapid access
processors, pressure desensitization and/or increased fog
can be controlled by selected combinations of addenda,
vehicles, hardeners and/or processing conditions, as illus-
trated by Abbott et al U.S. Patent 3,295,976, Barnes et al
U.S. Patent 3,545,971, Salesin U.S. Patent 3,708,303,
Yamamoto et al U.S. Patent 3,615,619, Brown et al U.S.
Patent 3,623,873, Taber U.S. Patent 3,671~258, Abele U.S.
Patent 3,791,830, Research Disclosure, Vol. 99, July 1972,
Item 9930, Florens et al U.S. Patent 3,843,364, Priem et al
U.S. Patent 3,867,152, Adachi et al U.S. Patent 3,967,965
and Mikawa et al U.S. Patents 3,947,274 and 3,954,474.
In addition to increasing the pH or decreasing
the pAg of an emulsion and adding gelatin, which are known
to retard latent image fading, latent image stabilizers can
be incorporated, such as amino acids, as illustrated by
Ezekiel U.K. Patents 1,335,923, 1,378,354, 1,387,654 and
1,391,672, Ezekiel et al U.K. Patent 1,394,371, Jef~erson
U.S. Patent 3,843,372, Je~ferson et al U.K. Patent 1,412,294
and Thurston U.K. Patent 1,343,904; carbonyl-bisulfite ~
addition products in combination with hydroxybenzene or ~-
aromatic amine developing agents, as illustrated by Seiter ~
et al U.S. Patent 3,424,583; cycloalkyl-1,3-diones, as `.
illustrated by Beckett et al U.S. Patent 3,447,926; enzymes
of the catalase type, as illustrated by Matejec et al U.S.
Patent 3,600,182; halogen-substituted hardeners in combina- ~
tion with certain cyanine dyes, as illustrated by Kumai et ..
al U.S. Patent 3,881,933; hydrazides, as illustrated by
3 Honig et al U.S. Patent 3,386,831; alkenylbenzothiazolium
salts, as illustrated by Arai et al U.S. Patent 3,954,478;
hydroxy-substituted benzylidene derivatives, as illustrated
by Thurston U.K. Patent 1,308,777 and Ezekiel et al U.K.
Patents 1,347,544 and 1,353,527; mercapto-substituted com-
pounds of the type disclosed by Sutherns U.S. Patent 3,519,427;metal-organic complexes of the type.disclosed by Matejec et
al U.S. Patent 3,639,128; penicillin derivatives, as illus-
trated by Ezekiel U.K. Patent 1,389,089; propynylthio
~.
: ~ ~ . "
~. :: . , : ~ , .
765
- 27 -
derivatives of benzimidazoles, pyrimidines, etc., as illus-
trated by von Konig et al U.S. Patent 3,910,791; combina-
tions of iridium and rhodium compounds, as disclosed by
Yamasue et al U.S. Patent 3,901,713; sydnones or sydnone
imines, as illustrated by Noda et; al U.S. Patent 3,881,939;
thiazolidine derivatives, as illustrated by Ezekiel U.K.
Patent 1,458,197 and thioether-substituted imidazoles, as
illustrated by Research Disclosure, ~ol. 136, August 1975,
Item 13651.
The photographic elements can be color photo-
graphic elements which form dye images through the selec-
tive destruction, formation or physical removal of dyes.
The photographic elements can produce dye images
through the selective destruction of dyes or dye precur-
15 sors, such as silver-dye-bleach processes, as illustrated
by A. Meyer, The Journal of Photographic Science, Vol. 13,
1965, pp. 90-97. Bleachable azo, azoxy, xanthene, azine,
phenylmethane, nitroso complex, indigo, quinone, nitro-
substituted, phthalocyanine and formazan dyes, as illus-
20 trated by Stauner et al U.S. Patent 3,754,923, Piller et al
U.S. Patent 3,749,576, Yoshida et al U.S. Patent 3,738,839, i~
Froelich et al U.S. Patent 3,716,368, Piller U.S. Patent
3,655,388, Williams et al U.S. Patent 3,642,482, Gilman
U.S. Patent 3,567,448, Loeffel U.S. Patent 3,443,953,
25 Anderau U.S. Patents 3,443,952 and 3,211,556, Mory et al
U.S. Patents 3,202,511 and 3,178,291 and Anderau et al U.S.
Patents 3,178,285 and 3,178,290, as well as their hydrazo,
diazonium and tetrazolium precursors and leuco and shifted
derivatives, as illustrated by U.K. Patents 923,265,
3 999,996 and 1,042,300, Pelz et al U.S. Patent 3,684,513,
Watanabe et al U.S. Patent 3,615,493, Wilson et al U.S.
Patent 3,503,741, Boes et al U.S. Patent 3,340,059, Gompf
et al U.S. Patent 3,493,372 and Puschel et al U.S. Patent
3,561,970, can be employed.
The photographic elements can produce dye images
through the selective ~ormation o~ dyes, such as by react-
ing ~coupling~ a color-developing agent ~e.g., a primary
'' ; '
-28-
aromatic amine~ in its oxidized form with a dye-~orming
coupler. The dye-forming couplers can be incorporated in
the photographic elements, as illustrated by Schneider et
al, Die Chemie, Vol. 57, 1944, p. 113, Mannes et al U.S.
Patent 2,304,940, Martinez U.S. Patent 2,269,158, Jelley et
al U.S. Patent 2,322,027, Frolich et al U.S. Patent
2,376,679, Fierke et al U.S. Patent 2,801,171, Smith U.S.
Patent 3,748,141, Tong U.S. Patent 2,772,163, Thirtle et al
U.S. Patent 2,835,579, Sa~dey et al U.S. Patent 2,533,514,
10 Peterson U.S. Patent 2,353,754, Seidel U.S. Patent
3,409,435 and Chen Research Disclosure, Vol. 159, July
1977, Item 15930.
In one form the dye-forming couplers are chosen
to form subtractive primary ~i.e., yellow, magenta and
cyan) image dyes and are nondiffusible, colorless couplers,
such as two and four equivalent couplers of the open chain
ketomethylene, pyrazolone, pyrazolotriazole, pyrazolobenz-
imidazole, phenol and naphthol type hydrophobically bal-
lasted for incorporation in high-boiling organic (coupler)
solvents. Such couplers are illustrated by Salminen et al
U.S. Patents 2,423,730, 2,772,162, 2,895,826, 2,710,803,
2,407,207, 3,737,316 and 2,367,531, Loria et al U.S.
Patents 2,772,161, 2,600,788, 3,006,759, 3,214,437 and
3,253,924, McCrossen et al U.S. Patent 2,875,057, Bush et
al .U.S. Patent 2,908,573, Gledhill et al U.S. Patent
3,034,892, Weissberger et al U.S. Patents 2,474,293,
2,407,210, 3,062,653, 3,265,506 and 3,384,657, Porter et al
U.S. Patent 2,343,703, Greenhalgh et al U.S. Patent
3,127,269, Feniak et al U.S. Patents 2,865,748, 2,933,391
and 2,865,751, Bailey et al U.S. Patent 3,725,067, Beavers
et al U.S. Patent 3,758,308, Lau U.S. Patent 3,779,763,
Fernandez U.S. Patent 3,785,829, U.K. Patent 969,921, U.K.
Patent 1,241,069, U.K. Patent 1,011,940, Vanden Eynde et al
U.S. Patent 3,762,921, Beavers U.S. Patent 2,983,608, Loria
U.S. Patents 3,311,476, 3,408,194, 3,458,315, 3,447,928,
3,476,563, Cressman et al U.S. Patent 3,419,390, Young U.S.
Patent 3,419,391, Lestina U.S. Patent 3,519,429, U.K.
Patent 975,928, U.K. Patent 1,111,554, Jaeken U.S. Patent
: , . ~ . ~ j : .
7~
3,222,176 and Canadian Patent 726,651, Schulte et al U.K.
Patent 1,248,924 and Whitmore et al U.S. Patent 3,227,550.
The photographic elements can incorporate alkali-
soluble ballasted couplers, as illustrated by Froelich et
al and Tong, cited above. The photographic elements can be
adapted to form non-diffusible image d~es using dye-forming
couplers in developers, as illustrated by U.K. Patent
478,984~ Yager et al U.S. Patent 3,113,864, Vittum et al
U.S. Patents 3,002,836, 2,271,238 and 2,362,598, Schwan et
al U.S. Patent 2,950,970, Carroll et al U.S. Patent
2,592,243, Porter et al U.S. Patents 2,343,703, 2,376,380
and 2,369,489, Spath U.K. Patent 886,723 and U.S. Patent
2,899,306, Tuite U.S. Patent 3,152,896 and Mannes et al
U.S. Patents 2,115,394, 2,252,718 and 2,108,602.
The dye-forming couplers upon coupling can
release photographically useful fragments, such as devel-
opment inhibitors or accelerators, bleach accelerators,
developing agents, silver halide solvents, toners, hard-
eners, fogging agents, antifoggants, competing couplers,
chemical or spectral sensitizers and desensitizers.
Development inhibitor-releasing (DIR) couplers are illus-
trated by Whitmore et al U.S. Patent 3,148,062, Barr et al
U.S. Patent 3,227,554, Barr U.S. Patent 3,733,201, Sawdey
U.S. Patent 3,617,291, Groet et al U.S. Patent 3,703,375,
QbbQtt et al U.S. Patent 3,615,506, Weissberger et al U.S.
Patent 3,265,506, Seymour U.S. Patent 3,620,745, Marx et al
U.S. Patent 3,632,345, Mader et al U.S. Patent 3,869,291,
U.K. Patent 1,201,110, Oishi et al U.S. Patent 3,642,485,
Verbrugghe U.K. Patent 1,236,767, Fu~iwhara et al U.S.
3 Patent 3,770,436 and Matsuo et al U.S. Patent 3,808,945.
DIR compounds which do not form dye upon reaction with
oxidized color-developing agents can be employed, as illus-
trated by Fujiwhara et al German OLS 2,529,350 and U.S.
Patents 3,928,041, 3,958,993 and 3,961,959, Odenwalder et
al German OLS 2~448,063, Tanaka et al German OLS 2,610,546,
Kikuchi et al U.S. Patent 4,049,455 and Credner et al U.S.
Patent 4,052,213. DIR compounds which oxidatively cleave
can~be employed, as illustrated by Porter et al U.S. Patent
3,379,529, Green et al U.S. Patent 3,o43,690, Barr U.S.
.. . : :,, ~
.
37~;5
- 30 -
Patent 3,364,022, Duennebier et al U.S. Patent 3,2~7,4L15
and Rees et al U.S. Patent 3,287,129.
The photographic elements can incorporate colored
dye-forming couplers, such as those employed to ~orm
5 integral masks for negative color images, as illustrated
by Hanson U.S. Patent 2,449,966, Glass et al U.S. Patent
2,521,908, Gledhill et al U.S. Patent 3,034,892, Loria U.S.
Patent 3,476,563, Lestina U.S. Patent 3,519,429, Friedman
U.S. Patent 2,543,691, Puschel et al U.S. Patent 3,028,238,
Menzel et al U.S. Patent 3,061,432 and Greenhalgh U.K.
Patent 1,035,959, and/or competing couplers, as illustrated
by Murin et al U.S. Patent 3,876,428, Sakamoto et al U.S.
Patent 3,580,722, Puschel U.S. Patent 2,998,314, Whitmore
U.S. Patent 2,808,329, Salminen U.S. Patent 2,742,832 and
15 Weller et al U.S. Patent 2,689,793.
The photographic elements can produce dye images
through the selective removal of dyes. Neg~tive or posi-
tive dye images can be produced by the im~obilization or
mobilization of incorporated color-providing substances
20 (e.g., redox dye-releasers) as a function of exposure and
development, as illustrated by U.K. Patents 1,456,413,
1,479,739, 1,475,265 and 1,471,752, Friedman U.S. Patent
2,543,691, Whitmore U.S. Patent 3,227,552, Bloom et al U.S.
Patent 3,443,940, Morse U.S. Patent 3,549,364, Cook U.S.
25 Patent 3,620,730, Danhauser U.S. Patent 3,730,71~, Staples
U.S. Patent 3,923,510, Oishi et al U.S. Patent 4,052,214
and Fleckenstein et al U.S. Patent 4,076,529.
The photographic elements can contain antistain
agents (i.e., oxidized developing agent scavengers) to
30 prevent developing agents oxidized in one dye image layer
unit from migrating to an adjacent dye image layer unit.
Such antistain agents include ballasted or otherwise non-
diffusing antioxidants, as illustrated by Weissberger et al
U.S. Patent 2,336,327, ~oria et al U.S. Patent 2,728,659,
Vittum et al U.S. Patent 2,360,290, Jelley et al U.S.
Patent 2,403,721 and Thirtle et al U.S. Patent 2,701,197.
To avoid autooxidation the antistain agents can be employed
in combination with other antioxidants, as illustrated by
Knechel et al U.S. Patent 3,700,453.
::.
~ . ,
- . .
' . . ' , . ' .:` ~: ~ ', " :'
. ~ :~ . ;:-
. ;. :: i :`: - `'` ' :
... ... .
: . . .:: . . -
~:~Z~
-31-
The photographic elements can include image dye
stabilizers. Such image dye stabilizers are illustrated by
U.K. Patent 1,326,889, Lestina et al U.S. Patents 3,432,300
and 3,698,909, Stern et al U.S. Patent 3,574,627, Brannock
et al U.S. Patent 3,573,050, Arai et al U.S. Patent
3,764,337 and Smith et al U.S. Patent 4,042,394. 3
The sensitizing dyes and other addenda incor-
porated into the layers of the photographic elements can be
dissolved and added prior to coating either from ~ater or
organic solvent solutions, depending upon the solubility of
the addenda. Ultrasound can be employed to dissolve
addenda, as illustrated by Owen et al U.S. Patent 3,485,634
and Salminen U.S. Patent 3,551,157. Semipermeable and ion
exchange membranes can be used to introduce addenda, such
as water soluble ions (e.g., chemical sensitizers).
Hydrophobic addenda, particularly those which need not be
adsorbed to the silver halide grain surfaces to be effec-
tive, such as couplers, redox dye-releasers and the like,
can be mechanically dispersed directly, as illustrated by
Belgian Patent 852,138, or in high boiling (coupler~ sol-
vents, as illustrated by Jelley et al U.S. Patent 2,322,027
and ~ierke et al U.S. Patent-2,801,171, or the hydrophobic
addenda can be loaded into latices and dispersed, as illus-
trated by Chen Research Disclosure, Vol. 159, July 1977,
Item 15930-
Exemplary apparatus and procedures for intro-
ducing and blending addenda are illustrated by Johnson et
al U.S. Patents 3,425,835, 3,570,818, 3,773,302 and `
3,850,643, McCrossen et al U.S. Patent 3,342,605, Collins
3 et al U.S. Patent 2,912,343 and Terwilliger et al U.S.
Patents 3J827~888 and 3,888,465.
In forming photographic elements the layers can
be applied to photographic supports by various procedures,
including immersion or dip coating, roller coating, reverse
roll coating, air knife coating, doctor blade coating,
gravure coating, spray coating, extrusion coating, bead
coating, stretch-flow coating and curtain coating. High
speed coating using a pressure differential is illustrated
by Beguin U.S. Patent 2,681,294. Controlled variation in
~ . .. . .
.
- , . : . : ,,
.
.. ..
., . ~
., - . , : . .. ..
¢)765
- 32 -
the pressure differential to facilitate coating starts isillustrated by Johnson U.S. Patent 3,220,877 and to
minimize splicing disruptions is illustrated by Fowble
U.S. Patent 3,916,043. Coating at reduced pressures to
accelerate drying is illustrated by Beck U.S. Patent
2,815,307. Very high speed curtain coating is illustrated l
by Greiller U.S. Patent 3,632,374. Two or more layers can
be coated simultaneously, as illustrated by Russell U.S.
Patent 2,761,791, Wynn U.S. Patent 2,941,898, Miller et al
U.S. Patent 3,206,323, Bacon et al U.S. Patent 3,425,857,
Hughes U.S. Patent 3,508,947, Herzhoff et al U.K. Patent
1,208,809, Herzhoff et al U.S. Patent 3,645,773 and
Dittman et al U.S. Patent 4,001,024. In simultaneous
multilayer coating varied coating hoppers can be used, as
illustrated by Russell et al U.S. Patent 2,761,417,
Russell U.S. Patents 2,761,418 and 3,474,758, Mercier et al
U.S. Patent 2,761,419, Wright U.S. Patent 2,975,754,
Padday U.S. Patent 3,oO5,Ll40, Mercier U.S. Patent 3,627,564,
Timson U.S. Patents 3,749,053 and 3,958,532, Jackson U.S.
20 Patent 3,993~019 and Jackson et al U.S. Patent 3,996,885.
Silver halide layers can also be coated by vacuum evapora-
tion, as illustrated by Lu Valle et al U.S. Patents
3,219,444 and 3,219,451.
The layers of the photographic elements can be
coated on a variety of supports. Typical photographic
supports include polymeric film, wood fiber--e.g., paper,
metallic sheet and foil, glass and ceramic supporting
elements provided with one or more subbing layers to en-
hance the adhesive, antistatic, dimensional, abrasive,
3 hardness, frictional, antihalation and/or other properties
of the support surface.
Typical of useful polymeric film supports are
films of cellulose nitrate and cellulose esters such as
cellulose triacetate and diacetate, polystyrene, poly-
amides, homo- and co-polymers of vinyl chloride, poly(vinyl
acetal~, polycarbonate, homo- and co-polymers of olefins,
such as polyethylene and polypropylene, and polyesters of
dibasic aromatic carboxylic acids with divalent alcohols,
such as poly~ethylene terephthalate~.
- . ,,., . ~ -
. ~ : ., . . ..
. ;~:: . : .
- : . ~.. . - . :
~7 6
- 33 -
Typical of useful paper supports are those which
are partially acetylated or coated with baryta and/or a
polyolefin, particularly a polymer of an ~-olefin contain-
ing 2 to 10 carbon atoms, such as polyethylene, polypropyl- :.
ene, copolymers of ethylene and propylene and the like.
Polyolefins, such as polyethylene, polypropylene
and polyallomers--e.g., copolymers of ethylene with propyl-
ene, as illustrated by Hagemeyer et al U.S. Patent
3,478,128, are preferably employed as resin coatings over
paper, as illustrated by Crawford et al U.S. Patent
3,411,908 and Joseph et al U.S. Patent 3,630,740, over
polystyrene and polyester film supports, as illustrated by
Crawford et al U.S. Patent 3,630,742, or can be employed as
unitary flexible reflection supports, as illustrated by
Venor et al U.S. Patent 3,973,963.
Preferred cellulose ester supports are cellulose
triacetate supports, as illustrated by Fordyce et al U.S.
Patents 2,492,977, '978 and 2,739,069, as well as
mixed cellulose ester supports, such as cellulose acetate
20 propionate and cellulose acetate butyrate, as illustrated
by Fordyce et al U.S. Patent 2,739,070.
Preferred polyester film supports are comprised
of linear polyester, such as illustrated by Alles et al
U.S. Patent 2,627,088, Wellman U.S. Patent 2,720,503, Alles
25 u.s. Patent 2,779,684 and Kibler et al U.S. Patent -:
2,901,466. Polyester films can be formed by varied tech-
niques, as illustrated by Alles, cited above, Czerkas et al `
U.S. Patent 3,663,683 and Williams et al U.S. Patent
3,504,075, and modified for use as photographic film
3 supports, as illustrated by Van Stappen U.S. Patent ~.
3,227,576, Nadeau et al U.S. Patent 3,501,301, Reedy et al
U.S. Patent 3,589,905, Babbitt et al U.S. Patent 3,850,640,
Bailey et al U.S. Patent 3,888,678, Hunter U.S. Patent
3,904,420 and Mallinson et al U.S. Patent 3,928,697.
The photographic elements can employ supports
hich are resistant to dimensional.change at elevated
temperatures. Such supports can be comprised of linear
condensation polymers which have glass transition tempera-
tures above about 190C, preferably 220C, such as poly-
., ,,,; - ,, . , , .
.,
~ . . .- ,. :: ::
13L;~(1~7~S
-34-
carbonates, polycarboxylic esters, polyamides, polysulfon-
amides, polyethers, polyimides, polysulfonates and copoly-
mer varian~s, as illustrated by Hamb U.S. Patents 3,634,089
and 3,772,405; Hamb et al U.S. Patents 3,725,070 and
3,793,249; Wilson Research Disclosure, Vol. 118, February
1974, Item 11833, and Vol. 120, April 1974, Item 12046; t
Conklin et al Research Disclosure~ Vol. 120, April 1974,
Item 12012; Product Licensing Index, Vol. 92, December
1971, Items 9205 and 9207; Research Disclosure, Vol. 101,
September 1972, Items 10119 and 10148; Research Disclosure,
Vol. 106, February 1973, Item 10613; Research Disclosure,
Vol. 117, January 1974, Item 11709, and Research Disclosure,
Vol. 134, June 1975, Item 13455.
The photographic elements of this invention show
particularly advantageous sensitivities when exposed to
light. The photographic elements are specifically contem-
plated for imagewise exposure under ordinary lighting
conditions--that is, less than high intensity lighting
conditions. Exposures can be monochromatic, orthochro-
matic or panchromatic. Imagewise exposures at ambient,elevated or reduced temperatures and/or pressures, con-
tinuous or intermettent exposures 3 exposure times ranging
from minutes to relatively short durations in the milli-
second to microsecond range and solarizing exposures, can
be employed within the useful response ranges determined
by conventional sensitometric techniques, as illustrated
by T. H. James, The Theory o~ the Photographic Process,
4th Ed., Macmillan, 1977, Chapters 4, 6, 17, 18 and 23.
Upon imagewise exposure the high chloride silver
3 halide grains form latent image sites at or near their sur-
face, both in their primitive state and after surface chemi-
cal sensitization, unless the emulsions as described above
are otherwise modified. Accordingly the emulsions can be
processed in all conventional silver halide developers--
including those containing sufficient silver halide solventto reveal internal latent image sites, referred to in the
art as surface and sub-surface developers, and those contain-
ing higher levels of silver halide solvents, referred to in
. . ~ .. :,, . .,.: : ~ . :
-35-
the art as internal developers. It is accordingly apparent
that the emulsions as described above are useful for photo-
graphic applications requiring negative-working silver halide
emulsions and photographic elements.
The light-sensitive silver halide contained in the
photographic elements can be processed ~ollowing exposure to
form a visible image by associating the silver halide with
an aqueous alkaline medium in the presence Or a developing
agent contained in the medium or the element. Processing
formulations and techniques are described in L. F. Mason,
Photographic Processing Chemistry, Focal Press, London,
1966; ProcessingChemicals and Formulas, Publication J-l,
~astman Kodak Company, 1973; Photo-Lab Index, Morgan and
Morgan, Inc., Dobbs Ferryg New York, 1977, and Neblette's
Handbook of Photography and Reprography - Materials, Processes
and Systems, VanNostrand Reinhold Company, 7th Ed., 1977.
Included among the processing methods are web
processing, as illustrated by Tregillus et al U.S. Patent
3,179,517; stabilization processing, as illustrated by Herz
et al U.S. Patent 3,220,839, Cole U.S. Patent 3,615,511,
Shipton et al U.K. Patent 1,258,906 and Haist et al U.S.
Patent 3,647~453; monobath processing as described in Haist,
Monobath ManuaI, Morgan and Morgan, Inc., 1966, Schuler U.S.
Patent 3,240,603, Haist et al U.S. Patents 3,615,513 and
3,628,955 and Price U.S. Patent 3,723,126; inf'ectious
development, as illustrated b'y Milton U.S. Patents 3,294,537,
3,600,174, 3,615,519 and 3,615,524, Whiteley U.S. Patent
3,516,830, Drago U.S. Patent 3,615,488, Salesin et al U.S.
Patent 3,625,689, Illingsworth U.S. Patent 3,632,340,
3 Salesin U.K. Patent 1,273,030 and U.S. Patent 3,708,303;
hardening development, as illustrated by Allen et al U.S.
Patent 3,232,761; roller transport processing, as illustrated
by Russell et al U.S. Patents 3,025,779 and 3,515,556,
Masseth U.S. Patent 3,573,914, Taber et al U.S. Patent
3,647,459 and Rees et al U.K. Patent 1,269,268; alkaline
vapor processing, as illustrated by Product Licensing Index,
Vol. 97, May 1972, Item 9711, Goffe et al U.S. Patent
3,816,136 and King U.S. Patent 3,985,564; metal ion develop- '
ment as illustrated by Price, Photogr'aphic Science and
. .
~2~7~
-36
En~ineering, Vol. 19, Number 5, 1975, pp. 283-287 and Vought
Research Disclosure, Vol. 150, October 1976, Item 15034;
reversal processing, as illustrated by Henn et al U.S.
Patent 3,5763633; and surface application processing, as
illustrated by Kitze U.S. Patent 3,418,132.
The photographic elements can be processed to
form dye images which correspond to or are reversals of the
silver halide rendered selectively developable by imagewise
exposure.
Multicolor reversal dye images can be formed in
photographic elements having differentially spectrally
sensitized silver halide layers by black-and-white devel-
opment followed by i) where the elements lack inco~porated
dye image formers, sequential reversal color development
15 with developers containing dye image formers, such as color
couplers, as illustrated by Mannes et al U.S. Patent
2,252,718, Schwan et al U.S. Patent 2,950,970 and Pilato
U.S. Patent 3,547,650; ii ) where the elem~ ts contain
incorporated dye image formers, such as color couplers, a
20 single color development step, as illustrated by the Kodak
Ektachrome E4 and E6 and Agfa processes described in
British Journal of Photograph~ Annual, 1977, pp. 194-197,
and British Journal of Photography, August 2, 1974, pp. 668-
669; and iii) where the photographic elements contain bleach-
25 able dyes, silver-dye-bleach processing, as illus-trated by
the Cibachrome P-10 and P-18 processes described in the
British Journal of Photogra~hy Annual, 1977, pp. 209-212. .
The photographic elements can be adapted for
direct color reversal processing (i.e., production of
30 re~ersal color images without prior black-and-white devel-
- opment), as illustrated by U.K. Patent 1,075,385, Barr U.S.
Patent 3,243,294, Hendess et al U.S. Patent 3,647,452,
Puschel et al German Patent 1,257,570 and U.S. Patents
3,457,077 and 3,467,520, Accary-Venet et al U.K. Patent
35 1,132,736, Schranz et al German Patent 1,259,700, Marx et
al German Patent 1,259,701 and Muller-Bore German OLS
2,005,091.
~ -
2~q6
-37-
Multicolor dye images which correspond to the
silver halide rendered selectively developable by imagewise
exposure, typically negative dye images, can be produced by
processing, as illustrated by the Kodacolor C-22, the Kodak
Flexicolor C-41 and the Agfacolor processes described in
British Journal of Photography Annual, 1977, pp. 201-205.
The photographic elements can also be processed by the
Kodak Ektaprint-3 and -300 processes as described in Kodak
Color Dataguide, 5th Ed., 1975, pp. 18-19, and the Agfa
10 color process as described in British Journal of Photog- )~
raphy Annual~ 1977, pp. 205-206, such processes being
particularly suited to processing color print materials,
such as resin-coated photographic papers, to form positive
dye images.
The photographic elements can be processed in the
presence of reducible species, such as transition metal ion
complexes (e.g. cobalt(III) and ruthenium~III) complexes
containing amine and/or ammine ligands~ and peroxy com-
pounds (e.g. hydrogen peroxide and alkali metal perborates
and percarbonates)-
Dye images can be formed or amplified by pro-
cesses which employ in combination with a dye-image-generat-
ing reducing agent an inert transition metal ion complex
oxidizing agent, as illustrated by Bissonette U.S. Patents
25 3,748,138, 3,826,652, 3,862,842 and 3,989,526 and Travis
U.S. Patent 3,765,891, and/or a peroxide oxidizing agent,
as illustrated by Matejec U.S. Patent 3,674,490, Research
Disclosure, Vol. 116, December 1973, Item 11660, and
Bissonette Research Disclosure, Vol. 148, August 1976,
3 Items 14836, 14846 and 14847. The photographic elements
can be particularly adapted to form dye images by such
processes, as illustrated by Dunn et al U.S. Patent 3,822,129,
Bissonette U.S. Patents 3,834,907 and 3,202,905, Bissonette
et al U.S. Patent 3,847,612 and Mowrey U.S. Patent 3,904,413.
The presence of transition metal ion complexes
can accelerate silver halide development, as illustrated by
Bissonette U.S. Patent 3,748,138, Beavers U.S. Patent
3,901,712 and Price U.S. Patent 3,964,212; can bleach silver
. .. :
.
-38 -
images, as illustrated by Bissonette U.S. Patent 3,923,511
and Research Disclosure, Item 14846, and can be employed to
~orm tanned colloid images, as illustrated b~ Bissonette
U.S. Patent 3,856,524 and McGuckin U.S. Patent 3,862,855.
The peroxide oxidizing agents can be employed to
form vesicular images, as illustrated by ~eyde U.S. Patent
3,615,491, Weyde et al U.K. Patent 1,329,444 and U.S. Patent
3,765,890, Meyer et al U.K. Patent 1,332,693, Liebe et al
German OLS 2,420,521 and Mate~ec et al U.S. Patent 3,776,730.
The emulsions and photographic elements of this
invention can rorm a part o~ an otherwise conventional
image transfer system. Image transfer systems include
colloid transfer systems~ as illustrated by Yutzy et al
U.S. Patents 2,596,756 and 2,716,059; silver salt diffusion
15 transfer systems, as illustrated by Rott U.S. Patent ~:
2,352,014, Land U.S. Patent 2,543,181, Yackel et al U.S.
Patent 3,020,155 and Land U.S. Patent 2,861,885; imbibition
transfer systems, as illustrated by Minsk U.S. Patent
2,882,156, and color image trans~er systems, as illustrated ~
by Research Disclosure, Vol. 151, November 1976, Item .
15162, and Vol. 123, July 1974, Item 12331.
Color image transfer systems (including emulsion
layers, receiving layers, timing layers, acid layers, pro-
cessing compositions, supports and cover sheets) and the .~-
25 images they produce can be varied by choosing among a ~.
variety of features, combinations of which can be used
together as desired.
Film units can be chosen which are either inte-
grally laminated or separated during exposure, processing
3 and/or viewing, as illustrated by Rogers U.S. Patent
2,983,606, Beavers et al U.S. Patent 3,445,228, Whitmore
Canadian Patent 674,082, Friedman et al U.S. Patent
3,309,201, Land U.S. Patents 2,543,181, 3,053,659,
3,415,644, 3,415,645 and 3,415,646 and Barr et al U.
Patent 1,330,524. ~
Positive-wor~ing chemistry can be chosen utiliz- `
ing initially mobile dyes which are immobilized by develop- ;
ment, as illustrated by Rogers U.3. Patent 2,983,606, Yutzy
U.S. Patent 2,756,142, Lestina et al U.S. Patent 3,880,658,
:~"
~21~7f~5
-39-
Bush et al U.S. Patent 3,854,945 and Janssens et al U.S.
Patent 3,839,c35, or initially immobile dyes which are
rendered mobile by development, as illustrated by Hinshaw
et al U.K. Patent 1, 464,104 and Fields U.S. Patent
3,980,479; or negative-working imaging chemistry can be
chosen utilizing the release of diffusible dyes from an
immobile image dye-forming compound (e.g., a redox dye-
releaser) as a function of development, as illustrated by
Belgian Patent 838,062, Whitmore et al Canadian Patent
602,607 and U.S. Patent 3,227,550, Bloom et al U.S. Patent
3,443,940, Puschel et al U.S. Patents 3,628,952 and
3,844,785, Gompf et al U.S. Patent 3,698,897, Anderson et
al U.S. Patent 3,725,062, Becker et al U.S. Patent
3,728,113, Fleckenstein U.S. Patent 4,053,312, Fleckenstein
et al U.S. Patent 4,076,529, r~elzer et al U.K. Patent
1,489,695, Degauchi German OLS 2,729,820 and Kestner et al
Research Disclosure, Vol. 151, November 1976, Item 15157.
An image to be viewed can be transferred from the
image-forming layers. A retained image can be formed for
20 viewing as a concurrently formed complement of the trans-
ferred image. Positive transferred images and useful
negative retained images can be formed when one of the
imaging chemistry and the emulsion is negative-working and
the other positive-working; and negative transferred images
25 and positive retained images can be formed when both the
imaging chemistry and the emulsion(s) are negative-working
or positive-working. Images retained in and transferred
from the image-forming layers are illustrated by U.K.
Patent 1,456,413, Friedman U.S. Patent 2,543,691, Bloom et
3 al U.S. Patent 3,443,940, Staples U.S. Patent 3,923,510 and
Fleckenstein et al U.S. Patent 4,076,529.
One-step processing can be employed, as illus-
trated by U.K. Patent 1,471,752, Land U.S. Patent 2,543,181,
Rogers U.S. Patent 2,983,606 ~pod processing~, Land U.S.
Patent 3,485,628 ~soak image-former and laminate to receiv-
er~ and Land U.S. Patent 3,907,563 ~soak receiver and
laminate to image-forming element~; or multi-step process-
ing can be employed, as illustrated by ~ut~y U.S. P~ltent
' ~
~2~ S
- 40 -
2,756,142, Whitmore et al U.S. Patent 3,227,550 and Faul et
al U.S. Patent 3,998,637.
Pre~ormed reflective layers can be employed as
illustrated by Whitmore Canadian Patent 674,082, Beavers
u.s. Patent 3,445,228, Land U.S. Patents 2,5L~3,181,
3,415,644, 3~415,645 and 3,415,646, and Barr et al U.K.
Patent 1,330,524; or processing-f`ormed reflective layers
can be employed, as illustrated by Land U.S. Patents
2,607,685 and 3,647,437, Rogers U.S. Patent 2,~83,606 and
Buckler U.S. Patent 3,661,585.
In addition to the silver halide emulsion and
photographic element features specifically indicated above,
it is appreciated that other conventional features requir-
ing no detailed description can also be present. For
15 example, the photographic elements can contain brighteners,
absorbing and scattering materials, hardeners, coating aids,
plasticizers and lubricants, antistatic layers, matting
a~ents, developing agents and development modi~iers as des-
cribed in Paragraphs V, VIII, X, XI, XII, XIII, XVI, XX and
XXI, of Research Disclosure, Vol. 176, December 1978, Item
17643. Still other conventional photographic features and
applications not inconsistent with this invention will be
readily apparent to those skilled in the art.
Product Licensing Index and Research Disclosure
25 are published by Industrial Opportunities Ltd., Homewell,
Havant, Hampshire, PO9 lEF, United Kingdom.
In a specific preferred form the photographic
elements of this invention are intended to produce multi-
color images which can be viewed in the elements or in a
3 receiver when the elements form a part of a multicolor
image transfer system. For multicolor imaging at least
three superimposed color-forming layer units are coated on
a support. Each of the layer units is comprised of at
- least one silver halide emulsion layer. At least one of
35 the silver halide emulsion layers, preferably at least ;~
one of the silver halide emulsion layers in each color
forming layer unit and most preferably each of the silver
halide emulsion layers, contain an emulsion according to
this invention substantially as described above. The
.. ...
-41-
emulsion layers of one of the layer units are primarily
responsive to the blue region of the spectrum, the emulsion
layers of a second of the layer units are primarily respon-
sive to the green region of the spectrum, and the emulsion
layers of a third of the layer units are primarily respon-
sive to the red region of the spectrum. Since the high
chloride silver halide emulsions exhibit only limited
native sensitivity to the visible portion of the spectrum,
the use of yellow filter dyes between ad;acent layer units
can be omitted in many instances and the layer units can be
coated in any desired order. The layer units each contain
in the emulsion layers or in adJacent hydrophilic colloid
layers at least one image dye providing compound. Such
compounds can be selected from among those described above.
Incorporated dye-forming couplers and redox dye-releasers
constitute exemplary preferred image dye providing means.
The blue, green and red responsive layer units preferably
contain yellow, magenta and red image dye providing means,
respectively.
'.: ', ~ ~' - '' .:
- . , . :-
... . ..
. .: : . ~.. ~ " ' :: - :
- : :, ::
~2~765
-42-
The invention is further illustrated by the
following examples.
Example 1
lA. A polydisperse silver chloride emulsion, mean grain
size about 0.45 ~m, was prepared in the following manner:
Two solutions were prepared as ~ollows:
Solution 1
(Placed in the Reaction Vessel)
Gelatin 100 g
10 Distilled Water 7000 ml
Sodium Chloride 425 g
Dissolve at 40C
Adjust pH to 3.0 with HN03
Solution 2
15 Silver Nitrate 850 g
Distilled Water to 2900 ml
total volume
Dissolve at 40C
Adjust pH to 3.0 with HNO3
To solution 1 were added 1.7 mg of a fog inhibiting
agent of the type described in Allen et al U.S. Patent
2,728,663. Solution 2 was then added to the reaction vessel,
at a constant flow rate, over a 40 minute period, with con-
tinuous agitation. Following precipitation the pH was
adjusted to 4.5, a pH coaguable gelatin derivative was added
to the emulsion, and the emulsion was washed using the pro-
cedure described in Example 3 of Yutzy et al U.S. Patent
2,614,929.
lB. A cadmium doped polydisperse silver chloride emul-
3 sion, mean grain size about 0.45 ~m, was prepared as described
above, except that 10 mg o~ cadmium chloride (1.1 x 10 5 mole/
Ag mole) were added to the reaction vessel 5 minutes after the
start of the precipitation.
The polydisperse silver chloride emulsions prepared
as described above were coated, unsensitized and optimally
gold sensitized~ on a cellulose acetate film support at cover-
ages of 6.90 g gelatin and 4.65 g Ag/m2. The coated elements
were then exposed through a graduated density step wedge,
developed for 5' in Kodak Developer DK-50, fixed, washed and
6 S
-43-
dried. The sensitometric results are set forth below in
Table II.
TABLE II
Cadmium Gold Relative
5 Internal DopantSensitized Speed
No No lO0
Yes No 132
No Yes 355
Yes yes 501
lO From Table II it can be seen that the inclusion o~ j
cadmium as a dopant in a polydisperse silver chloride emulsion
unexpectedly results in an increase in speed of the emulsion
compared to an emulsion similarly prepared but lacking a
cadmium dopant.
Example 2
2A. A monodisperse silver chloride emulsion (1.5 ~m)
was prepared in the following manner:
Three solutions were prepared as ~ollows:
Solution l
(Placed in the Reaction Vessel)
Gelatin lO0 g
Distilled Water 7000 ml
Dissolve at 40C
Ad~ust pH to 2.0
Solution 2
-
Sodium Chloride 425 g
Distilled Water to 2900 ml
total volume
Dlssolve at 40C
Solution 3
Silver Nitrate 850 g
Distilled Water to 2900 ml
total volume
Dissolve at 40C
To so:Lution l were added 2.5 g of a silver halide
ripening agent of the type describe~ in McBride U.S. Patent
3,271,157. The pAg o~.solution l was then adJusted to 8.0
using solution 2. Solutions 2 and 3 were then simultaneously
. - .:
,: . , : :, -
- . : . .
:,
~2~7 6
-44-
run into solution 1 over a 40 minute period using an
accelerated flow technique, maintaining the pAg at 8.o.
Following precipitation the pH was raised to 5.5, a pH
coaguable gelatin derivative was added to the emulsion,
and the emulsion was washed using the procedure described
in Example 3 of Yutzy et al U.S. Patent 2,614,929.
2B. A cadmium doped monodisperse silver chloride
- emulsion (1.5 ~m) was prepared as described above (A),
except that 10 mg of cadmium chloride (1.1 x 10 5 mole~Ag
mole) were added to the reaction vessel prior to the start
of the precipitation.
The monodisperse silver chloride emulsions pre-
pared as described above (A and B) were optimally gold
sensitized and coated and tested as described in Example
1. The sensitometric results are set forth below in Table
III.
TABLE III
Cadmium Relative
Internal Dopant Speed
No 100
Yes 162
From Table III it can be seen that the inclusion
of cadmium as a dopant in a monodisperse silver chloride
emulsion unexpectedly results in an increase in speed of
the emulsion compared to an emulsion similarly prepared
but lacking a cadmium dopant.
Example 3
A series of monodisperse silver chloride emul- ;
sions of approximately equal grain size (1.4-1.5 ~m) were
3 prepared by a method similar to that utilized in Example
2, except that varying amounts of cadmium c~hloride were
added to the reaction vessel 5 minutes after the start of
precipitation. The resulting emulsions were then opti-
mally gold sensitized, coated and processed as described
in Example 1. ~able I~ shows the concentrations of cadmium
chloride utillzed in the various emulsions. Relative
speeds for these emulsions are shown in Curve A in Figure
1.
~.
; .... ,
~ 7 ~ 5
-45
TABLE I~
Cadmium Chloride Emulsion
mg/~ mole Mole~Ag mole ~rain Siæe (.~-m)
No cadmium chloride added 1.5
5 o.5 2.75 X 10-6 1.4
1.0 5.5 X 10-6 1.5
2.0 1.1 X 10-5 1.5
4.0 2.2 X 10-5 1.5
8.o 4.4 x 10-5 1.5
1012.0 6.6 X 10-5 1.5
Example 4
A series of monodisperse silver chloride emulsions
were prepared by a method similar to that described in
Example 2, except that varying amounts of lead chloride were
added 5 minutes after the start of the precipitation. The
resulting emulsions were then optimally gold chemically
sensitized and processed as described in Example 1. Table V
shows the concentrations of lead chloride ~tilized. Relative
speeds are shown in Curve B in Figure 1. ~
20TABLE ~ :
Lead Chloride Emulsion
~:~ ~ V~ 6 r~ie Grain Size (~m)
No lead chloride added 1.5
1.0 3.6 X 10-6 1.4~ ~
. 2,0 7.2 X 10-6 1.5 ' ~.
4.0 1.4 X 10-5 1.5
Example 5
A series of monodisperse silver chloride emulsions
were prepared by a method similar to that described in
30 Example 2, except that the doped emulsions were prepared by ~-
adding 10 mg of either copper chloride or ~inc chloride to
the reaction vessel 5 minutes after the start of the precipi-
tation. The resulting emulsions were then optimally gold
chemically sensitized, coated and processed as described in
Example 1. Table ~I below shows the concentration of the
dopants utilized and the relative speeds are shown for the
copper and Zinc doped emulsions at points C and D, respec- :
tively, in Figure 1.
7 6
-46 -
TABLE ~I
Metal mg/AgMoles/Ag Emulsion
Dopant Mole Mole Grain Si~e (~m)
None --- --- 1. 5
CuC12 2.Q 1.5 X 10-5 1.6
ZnC12 2.01.47 x 10-5 1. 5
Example 6
A. A silver chlorobromide emulsion (:20 mole percent
bromide) lacking an internal metal dopant was prepared in
10 the following manner: )
Three solutions were prepared as follows:
Solution 1
(Placed in the Reaction Vessel)
Gelatin 100 g
Distilled water 7000 ml
Dissolve at 40C,
Ad~ust pH to 2.0
Solution 2
Sodium chloride 367 g
Potassium bromide 119 g
Distilled water to total
volume at 40C 2900 ml
Solution 3
Silver nitrate 850 g
Distilled water to total
volume 2900 ml
Dissolve at 40c
To solution 1 were added 2.5 g of a silver halide
ripening agent o~ the type disclosed in McBride U.S. Patent
3 3,271,157. The pAg of solution was then adjusted to 7.94
with solution 2. Solutions 2 and 3 were then simultaneous-
ly run into solution 4 over a 40 minute period using an
accelerated ~low technique, maintaining the pAg at 7.94.
Following precipitation a pH coagulable gelatin derivative
35 was added to the emulslon, and the emulsion was ~as~ed
using the procedure described in Example 3 o~ Yutzy et al
U.S. Patent 2,~14,92~.
B. A cadrnium doped silver chlorobromide emulsion
(20 mole percent bromide~, was prepared as described in
: .
- .: . . :,
.: i . : , ~
. ..,~, . .' . ' ., ! , .. ~
_L,7_
paragraph A above except that 10 mg of cadmium chloride (1.1
X 10 5 mole/Ag mole) were added to the reaction vessel 5
minutes after the start of the precipitation.
C. A silver chlorobromide emulsion (50 mole percent
bromide) was prepared as in Paragraph A, except that the
amounts of sodium chloride and potassium bromide utilized in
the preparation of solution 2 were 279 g and 2~8 g, respec-
tively.
D. A cadmium doped silver chlorobromide emulsion
(50 mole percent bromide) was prepared as described in
Paragraph C, except that the lQ mg of cadmium chloride (1.1
X 10 5 mole/Ag mole) were added to the reaction vessel 5
minutes after the start of precipitation.
E. The silver chlorobromide emulsions prepared in
Paragraphs A-D were optimally gold chemically sensitized,
coated and processed as described in Example 1. Table VII
shows the fog levels.
TABLE VII
AgClBr Cadmium Dopant
20 (mole mg~Ag~ole/Ag Emulsion
% Br) MoleMole _ Grain Size (~m)
NoneNone 1.0
2.01.1 X 10-5 1.0
NoneNone 0.8
2.a1.1 X 10-5 o.8 --
In Figure 2 a plot is provided of the increase in relative
speed versus the halide content. The increase in relative -
speed is obtained by taking the relative speed of a photo-
graphic element formed with an undoped, surface chemically
sensitized emulsion as 100 and plotting as an ordinate the
additional speed of an otherwise identical element formed
with an emulsion differing by containing a dopant, as
described above. The abscissa is plotted in terms of mole
percent, the mole percent chloride in the silver halide ;
emulsion being the numerator and the mole percent bromide
in the silver halide emulsion being the denominator.
Example 7
A series of six monodisperse silver chloroiodide
emulsions (0.7 ~m~, were prepared in a manner similar to
'7
~48-
Example 2 except that a constant flow technique was ut:lized
rather than an accelerated flow and the precipitation was
carried out at a temperature of 6QC. The emulsion series
contains two siiver chloroiodide emulsions (undoped and
doped with 2 mg/Ag mole of cadmium chloride~ at each of
three separate chloride/iodide ratios, lQ0~0, ~8~2 and 96/4.
The emulsions having these chloride/iodide ratios were pre-
pared by adding either 0, 16.6 or 33.2 g of potassium iodide,
respectively, to solution 2 prior to precipitation. The
resulting emulsions were coated, exposed and processed by the
method described in Example 1. In Figure 3 a plot is pro-
vided of the increase in relative speed achieved by doping
versus the halide ratio.
Example 8
Two incorporated coupler color print materials
were prepared in the same manner, except differing in the
emulsions utilized in the blue-sensitive, yellow dye-
forming layer. The multilayer coatings were prepared in
the following manner:
Separate portions of a polyethylene coated paper
support were coated with gelatin layers comprising the
yellow dye-forming coupler ~-[4-(4-benzyloxyphenylsulfonyl~
phenoxy]-~-pivalyl-2-chloro-5-[y-butyramido]-acetanilide
at a coverage of 1.07 g/m and optimally gold chemically
sensitized silver chloride emulsions prepared as described
in Example 2 at a coverage of 0.33 g Ag/m2. The silver
chloride emulsions were both spectrally sensitized to the
blue region of the visible spectrum using a blue spectral
sensitizer. The rest of the multilayer coating for each of
the above variations are common and are described as a
gelatin interlayer comprising gelatin and an antistain
agent; a magenta dye-forming layer comprising a green-
sensitized silver chloride emulsion, a magenta dye-forming
coupler and gelatin; an interlayer comprising gelatin, an
antistain agent and a UV absorber; a cyan dye-~orming layer
comprising a red sensitized silver chloride emulsion, a cyan
dye-forming coupler and gelatin and a protective overcoat
layer comprising gelatin. The multilayer photosensitive ;
.
.. ..
' : ' '' ' ~
-49-
elements were then exposed to a tungsten light source
through a graduated density step wedge and processed in a
3-solution color process of the type described in Edens et
al U.S. Reissue Patent ~8,112. The relative blue sensi-
tivities of the two processed materials are shown in TableVIII.
TABLE VIII
Emulsion in Blue- Cadmium Relative
Sensitive, Yellow Chloride Blue
Dye-Forming_Layer Dopant Sensitivity
AgC1 None 100
AgCl2 mg/Ag Mole 182
Example 9
Two multicolor negative image-forming elements
suitable for use in a color image transfer process, wherein
color prints are obtained through the use of color nega-
tives, were prepared. The elements were identical, except
for the emulsions utilized in the blue sensitized, yellow
dye-releasing unit. The elements were prepared as des-
cribed below. The quantities of components are stated as
grams/meter2 in parenthesis. Silver halide quantities are
given in terms of silver.
A poly(ethylene terephthalate~ film support
coated on one side with a carbon-pigmented gelatin layer
was coated on the other side with the following layers:
(1) a cyan dye-providing layer comprising a disper-
sion of a cyan redox dye-releaser and gelatin;
(2) a light-sensitive layer comprising a red sensi-
tized, chemically sensitized silver chloride
emulsion;
3 (3) interlayer comprsing gelatin and an antistain
agent;
(4) a magenta dye-providing layer comprising a
dispersion of a magenta redox dye-releaser and
gelatin,
(5) a light-sensitive layer compring a green sensi-
tized, chemically sensitized silver chloride ~-
emulsion and gelatin; ~
.. .. -,. ...
: , - ,,., .. .: ~
. : : : : : -
- . .: : . ::
,: :: :- :
-50-
(6) interlayer comprising gelatin and an antistain
agent;
(7) a yellow dye-providing layer comprising a dis-
persion of Compound A~ ~a yellow redox dye-
releaser) (0.49) and gelatin Cl. 07);
Separate samples of ~he above-described element were then i ,
overcoated with layers comprising gelatin (1.07~ and
chemically sensitized silver chloride (0.30) emulsions
prepared either as described in Control 4 or as in Example
10 1. The silver chloride emulsions ~ere both spectrally
sensitized to the blue region o~ the visible spectrum
using a blue spectral sensitizer. Each sample was pro-
vided with a gelatin overcoat layer.
*Compound A
OH
t ~ C O N ( C, 8 H 3 7 ) 2
NHSO~ HO
2 0 O~s ~ - N= N- o~ 1 6 6
= N
Cl CN
Samples of each element were identically exposed to blue
ligh,t through a graduated density test ob~ect and pro-
cessed as follows:
The exposed elements were soaked for 10 seconds
at 28C in an activator solution comprising water to 1000
ml, benzyl alcohol (10 ml), 5-methylbenzotriazole (1 g),
3 ll-aminoundecanoic acid (2 g~ and 6-aminohexanoic acid,
laminated to a receiving element Cdescribed below~ for 2
1/2 minutes at 24C, and then peeled apart. The trans-
ferred yellow dye images produced in the receiving element ,,
were evaluated and the results are shown below in Table ~"~
IX.
7 6 5
-51-
TABLE IX
Cadmium Relative
Emulsion in Blue- Chloride Blue
Sensitive Layer . Dopant Sensitivity
AgCl None lO0
AgCl 2 m~/Ag Mole 162
Receiving Element
The receiving element utilized comprised a paper
support overcoated with a white-pigmented polyethylene
layer, an acid layer comprising co-poly(styrene-maleic
anhydride), a polymeric timing layer, a receiving layer
comprising gelatin, 4-hydroxymethyl4-methyl-1-phenyl-3-
pyrazolidone, poly(N-vinylimidazole-co-3-hydroxyethyl-l-
vinylimidazolium chloride) (90:10 weight ratio) and a
gelatin overcoat layer.
The invention has been described with particular
reference to certain preferred embodiments thereof but it
will be understood that variations and modi~ications can
be effected within the spirit and scope of the invention.
- .
.~ . .
.:
