U.S. patent application number 10/387078 was filed with the patent office on 2003-12-11 for novel blocked phenylenediamine developers for a color photographic element.
Invention is credited to Irving, Lyn M., Szajewski, Richard P..
Application Number | 20030228548 10/387078 |
Document ID | / |
Family ID | 22786328 |
Filed Date | 2003-12-11 |
United States Patent
Application |
20030228548 |
Kind Code |
A1 |
Szajewski, Richard P. ; et
al. |
December 11, 2003 |
Novel blocked phenylenediamine developers for a color photographic
element
Abstract
The present invention relates to a novel blocked
phenylenediamine developer useful, in reactive association, for
enabling, on development, a non-magenta color, for example a cyan
color, from a dye-forming coupler. In one embodiment, the developer
has the property that the dye color formed with the coupler is
distinctly different from the color formed by the same coupler with
an oxidized form of the conventional developer
4-(N-ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine. The
invention is also directed to a light-sensitive silver-halide color
photographic element comprising the blocked developing agent
according to the present invention.
Inventors: |
Szajewski, Richard P.;
(Rochester, NY) ; Irving, Lyn M.; (Rochester,
NY) |
Correspondence
Address: |
Paul A. Leipold
Patent Legal Staff
Eastman Kodak Company
343 State Street
Rochester
NY
14650-2201
US
|
Family ID: |
22786328 |
Appl. No.: |
10/387078 |
Filed: |
March 12, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10387078 |
Mar 12, 2003 |
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09871522 |
May 31, 2001 |
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6570034 |
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60211299 |
Jun 13, 2000 |
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Current U.S.
Class: |
430/543 |
Current CPC
Class: |
G03C 2200/21 20130101;
G03C 5/261 20130101; G03C 7/3005 20130101; G03C 7/407 20130101;
G03C 1/498 20130101; Y10S 430/156 20130101; Y10S 430/16 20130101;
G03C 7/30511 20130101; G03C 8/408 20130101; G03C 1/42 20130101;
G03C 7/30 20130101; G03C 7/30541 20130101 |
Class at
Publication: |
430/543 |
International
Class: |
G03C 007/26; G03C
007/32 |
Claims
In the claims:
1. Please cancel claims 1-16 and substitute the following claims
17-27.
17. A light sensitive color photographic imaging element comprising
at least one blocked developing agent having the following
structure: 22wherein, DEV is a silver-halide color developing
agent; LINK 1 and LINK 2 are linking groups; TIME is a timing
group; is 0 or 1; m is 0, 1, or 2; n is 0 or 1; 1+n is 1 or 2; B is
a blocking group or B is: --B'--(LINK 2).sub.n-(TIME).sub.m-(LINK
1).sub.1-DEV wherein B' also blocks a second developing agent DEV;
wherein the blocked developer liberates a developing agent within
the following structure: A-(CR.sup.1.dbd.CR.sup.2- ).sub.n--NHY
wherein: n is 0, 1 or 2; A is OH, or NR.sup.3R.sup.4; Y is H, or a
group that cleaves before or during a coupling reaction to form YH;
and R.sup.1 R.sup.2, R.sup.3 and R.sup.4, which can be the same or
different are individually H, alkyl, substituted alkyl, alkenyl,
substituted alkenyl, aryl, substituted aryl, halogen, cyano,
alkoxy, substituted alkoxy, aryloxy, substituted aryloxy, amino,
substituted amino, alkylcarbonamido, substituted alkylcarbonamido,
arylcarbonamido, substituted arylcarbonamido, alkylsulfonamido,
arylsulfonamido, substituted alkylsulfonamido, substituted
arylsulfonamido, or sulfamyl or wherein at least two of R.sup.1
R.sup.2, R.sup.3 and R.sup.4 together can further form a
substituted or unsubstituted carbocyclic or heterocyclic ring
structure, and wherein the blocked developer according to the
present invention enables the formation of a cyan colored dye when
the oxidized form of the released developer reacts with a coupler
having the following structure: 23
18. A light sensitive color photographic imaging element comprising
at least one blocked developing agent having the following
structure: DEV-(LINK 1).sub.1-(TIME).sub.m-(LINK 2).sub.n-B I
wherein, DEV is a silver-halide color developing agent; LINK 1 and
LINK 2 are linking groups; TIME is a timing group; 1 is 0 or 1; m
is 0, 1, or 2; n is 0 or 1; 1+n is 1 or 2; B is a blocking group or
B is: -B'-(LINK 2).sub.n-(TIME).sub.m-(LINK 1).sub.1-DEV wherein B'
also blocks a second developing agent DEV; wherein the blocked
developer liberates a developing agent within the following
structure: 24wherein R.sub.1, R.sub.1, R.sub.2, R.sub.2, R.sub.3
and R.sub.4 which can be the same or different are individually H,
alkyl, substituted alkyl, alkenyl, substituted alkenyl, aryl,
substituted aryl, halogen, cyano, hydroxy, alkoxy, substituted
alkoxy, aryloxy, substituted aryloxy, amino, substituted amino,
alkylcarbonamido, substituted alkylcarbonamido, arylcarbonamido,
substituted arylcarbonamido, alkylsulfonamido, arylsulfonamido,
substituted alkylsulfonamido, substituted arylsulfonamido, or
sulfamyl or wherein at least two of R.sub.1, R.sub.1, R.sub.2,
R.sub.2, R.sub.3 and R.sub.4 together further form a substituted or
unsubstituted carbocyclic or heterocyclic ring structure; except
that neither R.sub.1 nor R.sub.1 can be H.
19. The light sensitive color photographic imaging element
comprising at least one blocked developing agent according to claim
18 wherein the blocked developing agent liberates a developer
represented by the following structure. 25wherein R.sub.1 and
R.sub.1 are as described above.
20. The light sensitive color photographic imaging element of claim
18 comprising at least one blocked developing agent wherein the
developer is selected from the group consisting of
4-N,N-diethyl-2-methyl-6-methoxyphe- nylenediamine,
4-N,N-diethyl-2,6-dimethylphenylenediamine,
4-(N-ethyl-N-2-methanesulfonylaminoethyl)-2,6-dimethylphenylenediamine,
4-(N-ethyl-N-2-hydroxyethyl)-2,6-dimethylphenylenediamine,
4-N,N-diethyl-2-methanesulfonylaminoethyl-6-methylphenylenediamine,
4-(N-ethyl-N-2-hydroxyethyl)-2-ethoxyphenylenediamine, and
4-(N-ethyl-N-2-methoxyethyl)-2,6-dimethylphenylenediamine.
21. The light sensitive color photographic imaging element
comprising at least one blocked developing agent according to claim
17 wherein the developing agent has an E.sub.1/2 at pH 11 less
positive than 200 mV.
22. The light sensitive color photographic imaging element of claim
18 comprising a blocked developing agent liberating a developing
agent enabling cyan color from the a coupler, in reactive
association with the developing agent, on development.
23. The light sensitive color photographic imaging element of claim
18, wherein the element comprises a red-light-sensitive layer unit,
a green-light-sensitive layer unit and a blue-light-sensitive layer
unit wherein at least one layer unit has in reactive association
the blocked developing agent and a dye forming coupler.
24. The color photographic imaging element of claim 18, wherein
said element is a photothermographic element.
25. The color photographic imaging element of claim 18, wherein
said blocked developer is in reactive association with the red
light sensitive color layer unit.
26. The color photographic imaging element of claim 18, wherein an
imagewise exposed element is developed by heat treatment.
27. The color photographic imaging element of claim 18, wherein an
imagewise exposed element is developed by treatment with base
either by contacting the element to a pH controlling solution or by
contacting the element to a pH controlling laminate.
Description
FIELD OF THE INVENTION
[0001] The present invention is directed to novel blocked color
developers for photographic imaging element. In particular, the
blocked developer is a phenylenediamine developing agent that can
be incorporated into the imaging element to produce a distinct
color.
BACKGROUND OF THE INVENTION
[0002] Japanese kokai JP 10090854 (1996) teaches different
developers in the same color unit layer (having spectral
sensitivity in the same wavelength range) in a photothermographic
imaging element, in order to obtain better image or tone
gradation.
[0003] U.S. Pat. No. 6,197,722 B1 to Irving et al. teaches a method
of imaging, useful comprising providing an imaging member having at
least one light insensitive layer comprising a catalytic center and
multifunctional dye forming coupler, imagewise applying distinct
developer solutions that will react with the multifunctional dye
forming coupler to produce dyes of different colors. A preferred
method of imagewise application of developer solution is by the
technique known as "ink jet."
[0004] R. L. Bent et al., in Photographic Science and Engineering,
Vol. 8, No. 3, May-June 1964 disclosed that the frequencies of
maximum absorption of various dyes derived from p-phenylenediamines
are closely related to the half-wave oxidation potentials of the
compounds. As one point on various plotted correleations,
experimental Compound A is disclosed (in Table II), in a
4-amino-N,N-dialkylaniline structure has 3,5-di-CH.sub.3
substitution. The compounds are not disclosed as having any
commercial utility and the reference might be construed as teaching
that the use of Compound A would not be useful, since it would not
provide the desired magenta hue with a conventional magenta
coupler.
PROBLEM TO BE SOLVED BY THE PRESENT INVENTION
[0005] Light-sensitive imaging elements which form yellow, magenta
and cyan dye records of comparable density-forming ability and
consistent stability in all three color records using conventional
developers can be difficult. Cyan and yellow dye records can be a
problem in this regard, especially in photothermographic elements.
Accordingly, alternative ways of forming cyan or yellow dyes are
especially useful in such imaging elements.
[0006] Another problem with conventional cyan dye-forming couplers
relates to the fact that the raw stock stability of photographic
elements is influenced by the physical properties of materials
employed to formulate that element. Cyan dye-forming couplers are
particularly prone to crystallization on extended cold keeping.
This crystallization both degrades the image-forming ability of
such an element and mars the appearance of images produced in such
an element. This problem can be particularly acute in
photothermographic or heat developable elements since it may be
desirable to keep these elements cold before use, in order to
prevent premature reaction.
SUMMARY OF THE INVENTION
[0007] The present invention relates to a novel blocked
phenylenediamine developer useful, in reactive association, for
enabling, on development, a non-magenta color, for example a cyan
color, from a dye-forming coupler.
[0008] In one embodiment, the developer has the property that the
dye color formed with the coupler is distinctly different from the
color formed by the same coupler with an oxidized form of the
conventional developer
4-(N-ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine. In one
embodiment, the developer has the property that it is capable of
forming a distinctly colored cyan dye with one coupler, while the
same coupler forms a magenta dye with an oxidized form of the
conventional developer
4-(N-ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine. The latter
developer (also known as "CD2"), which developer is widely used, is
used herein as a standard means for the purpose of enabling a
convenient color comparison, but other developers could have been
substituted instead.
[0009] In a first embodiment, a light-sensitive silver-halide color
photographic element has a red-light-sensitive silver-halide layer
unit and a first blocked coupling developer, a
green-light-sensitive silver-halide layer unit and a second blocked
coupling developer, and a blue-light-sensitive silver-halide layer
unit having a third blocked coupling developer, wherein at least
two of the first, second, and third blocked coupling developers are
different and wherein at least one layer unit, or imaging layer in
the layer unit, has a blocked developer according to the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0010] As mentioned above, the invention relates to novel blocked
developer that can be used in a light-sensitive color photographic
imaging element comprising at least one chromogenic coupler in
reactive association with the blocked developer. In one embodiment,
the blocked developer liberates a developing agent enabling cyan
color from the coupler on development, wherein the same coupler
forms at least one other distinctly colored dye with an oxidized
form of the conventional developer
4-(N-ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine. The blocked
developer (or "developer precursor") liberates a phenylenediamine
type of developer as described in more detail below.
[0011] Thus, the developer according to the present invention can
have a number of possible uses, including use in imaging elements
having a number of different couplers and a number of different
developing agents. There can be two different couplers or three
different couplers in the imaging element. It is possible to have
more than three couplers, per the Japanese kokai mentioned above.
It is also possible to have more than three different developers
(or blocked developers), three different developers (or blocked
developers), two different developers (or blocked developers), or a
single developer (or blocked developer). In one embodiment, there
are two different developers and three different couplers, which
may minimize costs by not having more than two developers.
[0012] Thus, the developer can be employed in an imaging element
comprising, for example, a red-light-sensitive layer unit, a
green-light-sensitive layer unit and a blue-light-sensitive layer
unit, wherein at least one layer in at least two different layer
units has in reactive association an independently selected dye
forming coupler and an independently selected blocked developer.
Preferably, the blocked developer is different in two layer units.
Alternatively, the imaging element can comprise a
red-light-sensitive layer unit, a green-light-sensitive layer unit
and a blue-light-sensitive layer unit, wherein all three layer
units have in reactive association an independently selected dye
forming coupler and an independently selected blocked developer,
wherein the dye coupler is different in each layer unit and the
developing agent is the same in two layer units. As a further
alternative, the element can comprises a red-light-sensitive layer
unit, a green-light-sensitive layer unit and a blue-light-sensitive
layer unit, wherein all three layer units have in reactive
association an independently selected dye-forming coupler and an
independently selected blocked developer, wherein the dye couplers
are the same in only two of the layer units and wherein the blocked
developer is different in said two layer units. Alternatively, the
element can comprise a red-light-sensitive layer unit, a
green-light-sensitive layer unit and a blue-light-sensitive layer
unit, wherein two layer units have in reactive association a common
dye-forming coupler, wherein the third layer unit has a distinct
coupler, and wherein the blocked developer is the same in two of
the layer units.
[0013] In a preferred variant, the element is a photothermographic
element. In this embodiment, an imagewise exposed element is
developed by heat treatment. In another variant of the first
embodiment, an imagewise exposed element is developed by treatment
with base either by contacting the element to a pH controlling
solution or by contacting the element to a pH controlling
laminate.
[0014] When the formed image is intended for human viewing, a first
blocked coupling developer is cyan dye forming, a second blocked
coupling developer is magenta dye forming, and a third blocked
coupling developer is yellow dye forming. Preferably, developer of
the present invention is present, in reactive association with a
coupler, in the red light sensitive color layer unit. However, if
the formed image is to be scanned, it is possible to produce other
colored dyes.
[0015] The term "developer precursor" includes "blocked developer"
and other compounds that convert or otherwise react to form a
developing agent. The developer precursors are preferably supplied
in a blocked form as described below and elsewhere. These developer
precursors can release any developers known in the art which are
coupling developers and enable the formation of distinctly colored
dyes from the same coupler. By "distinctly colored" is meant that
the dyes formed differ in the wavelength of maximum adsorption by
at least 50 nm. It is preferred that these dyes differ in the
maximum adsorption wavelength by at least 65 nm and more preferred
that they differ in the maximum adsorption wavelength by at least
80 nm. It is further preferred that at least a cyan, a magenta, and
a yellow dye are formed. Preferably a cyan dye-forming developer, a
magenta dye-forming developer and a yellow dye-forming developer
are employed to form respectively cyan, magenta and yellow dyes
from the same coupler. In another embodiment, a black dye forming
developer is additionally employed. In yet another embodiment
multiple cyan dye forming, magenta dye forming and yellow dye
forming developers can be individually employed to form a greater
gamut of colors or to form colors at greater bit depth.
[0016] Typically, a cyan dye is a dye having a maximum absorption
at between 580 and 720 nm, with preferably a maximum absorption
between 590 and 680 nm, more preferably a peak absorption between
600 and 670 nm and most preferably a peak absorption between 605
and 655 nm. Typically, a magenta dye is a dye having a maximum
absorption at between 500 and 580 nm, with preferably a maximum
absorption between 515 and 565 nm, more preferably a peak
absorption between 520 and 560 nm and most preferably a peak
absorption between 525 and 555 nm. Typically, a yellow dye is a dye
having a maximum absorption at between 400 and 500 nm, with
preferably a maximum absorption between 410 and 480 nm, more
preferably a peak absorption between 435 and 465 nm and most
preferably a peak absorption between 445 and 455 nm. The
concentrations and amounts of the distinct developers and the
dye-forming coupler will typically be chosen so as to enable the
formation of dyes having a density at maximum absorption of at
least 0.7, preferably a density of at least 1.0, more preferably a
density of at least 1.3 and most preferably a density of at least
1.6. For cyan, magenta or yellow dyes, these will be densities
measured in a photographic element using status M filters. Further,
the dyes will typically have a half height band width (HHBW) of
between 70 and 170 nm in the region between 400 and 700 nm.
Preferably, the HHBW will be less than 150 nm, more preferably less
than 130 nm and most preferably less than 115 nm. Additional
details of preferred dye hues for images intended for direct
viewing are described by McInerney et al in U.S. Pat. Nos.
5,679,139, 5,679,140, 5,679,141 and 5,679,142, the disclosures of
which are incorporated by reference.
[0017] The blocked developer according to the present invention
enables the formation of a cyan colored dye when the oxidized form
of the released developer reacts with the coupler A-5 (defined
above), wherein developer is a compound selected from the class of
compounds represented by the following structure:
A-(CR.sup.1.dbd.CR.sup.2).sub.n--NHY (I)
[0018] wherein:
[0019] n is 0, 1 or 2;
[0020] A is OH, or NR.sup.3R.sup.4;
[0021] Y is H, or a group that cleaves before or during a coupling
reaction to form YH; and
[0022] R.sup.1 R.sup.2, R.sup.3 and R.sup.4, which can be the same
or different are individually H, alkyl, substituted alkyl, alkenyl,
substituted alkenyl, aryl, substituted aryl, halogen, cyano,
alkoxy, substituted alkoxy, aryloxy, substituted aryloxy, amino,
substituted amino, alkylcarbonamido, substituted alkylcarbonamido,
arylcarbonamido, substituted arylcarbonamido, alkylsulfonamido,
arylsulfonamido, substituted alkylsulfonamido, substituted
arylsulfonamido, or sulfamyl or wherein at least two of R.sup.1
R.sup.2, R.sup.3 and R.sup.4 together can further form a
substituted or unsubstituted carbocyclic or heterocyclic ring
structure. Preferably, (CR.sup.1.dbd.CR.sup.2).sub.n forms an
aromatic ring, more preferably a phenylene ring that can further be
substituted or unsubstituted.
[0023] In one preferred embodiment, in Structures I, the partial
structure --(CR.sup.1.dbd.CR.sup.2).sub.n-- represents a
substituted or unsubstituted phenylene moiety. When
--(CR.sup.1.dbd.CR.sup.2).sub.n-- represents an aromatic moiety,
the moieties -A and --NHY are preferably in a para relationship,
one to another.
[0024] In Structure I, when Y is a group that cleaves before or
during a coupling reaction to form YH, then Y is preferably the
moiety Q-R.sup.6 wherein:
[0025] R.sup.6 is H, alkyl, substituted alkyl, alkenyl, substituted
alkenyl, alkynyl, substituted alkynyl, aryl, substituted aryl,
heterocyclic or substituted heterocyclic, and Q is --SO.sub.2--,
--SO--, --SO.sub.3--, --CO--, --COCO--, --CO--O--, --CO(NR7)--,
--COCO--O, --OCO--N(R.sup.7)-- or --SO.sub.2--N(R.sup.7)--, where
R.sup.7 is H or the groups described in R.sup.6.
[0026] In the developer structures described herein, the word
"substituted" at each occurrence represents any group other than H
needed to satisfy the required valence where the group does not
adversely affect the required properties. The word "substituted"
preferably represents one or more of a linear or branched
carbonaceous group which can be cyclic or acyclic, a heterocyclic
group, an aromatic carbonaceous group, an arylalkyl group, a
halogen atom, a cyano group, a nitro group, a ureido group, an
ether group, an ester group, an amine group, an amide group, a
thioether group, a thioester group, a sulfonyl group or a sulfamyl
group.
[0027] Preferably, the imaging element comprises a blocked form of
a developer that results in a cyan dye being formed when the
oxidized form of the developer is reacted with the coupler of the
present invention. Preferably, the developer is the neutral or
photographically acceptable salt form of the compound represented
by the following Structure II. 1
[0028] R.sub.1, R.sub.1, R.sub.2, R.sub.2, R.sub.3 and R.sub.4which
can be the same or different are individually H, alkyl, substituted
alkyl, alkenyl, substituted alkenyl, aryl, substituted aryl,
halogen, cyano, hydroxy, alkoxy, substituted alkoxy, aryloxy,
substituted aryloxy, amino, substituted amino, alkylcarbonamido,
substituted alkylcarbonamido, arylcarbonamido, substituted
arylcarbonamido, alkylsulfonamido, arylsulfonamido, substituted
alkylsulfonamido, substituted arylsulfonamido, or sulfamyl or
wherein at least two of R.sub.1, R.sub.1, R.sub.2, R.sub.2, R.sub.3
and R.sub.4 together further form a substituted or unsubstituted
carbocyclic or heterocyclic ring structure; except that neither
R.sub.1 nor R.sub.1 can be H. Preferably, the substituents on
R.sub.1 and R.sub.1' have at least one carbon or halogen atom.
[0029] Preferably, R.sub.1 and R.sub.1 is independently a
substituted or unsubstituted alkyl or alkoxy or an
alkylsulfonamido, more preferably a C1 to C4 alkyl or alkoxy, most
preferably, the alkyl is an n-alkyl substituent. Preferably,
R.sub.2 and R.sub.2 are hydrogen. Preferably, R.sup.3 and R.sup.4
are independently hydrogen or a substituted or unsubstituted alkyl
group or R.sup.3 and R.sup.4 are connected to form a ring;
[0030] More preferably, the developer is the neutral or
photographically acceptable salt form of the compound represented
by the following Structure III: 2
[0031] Wherein R.sub.1 and R.sub.1' are as described above.
[0032] Some specific examples of developers according to the
present invention include, but are not limited to, the oxidized
form of a color developer chosen from the group consisting of
4-N,N-diethyl-2-methyl-6-me- thoxyphenylenediamine,
4-N,N-diethyl-2,6-dimethylphenylenediamine,
4-(N-ethyl-N-2-methanesulfonylaminoethyl)-2,6-dimethylphenylenediamine,
4-(N-ethyl-N-2-hydroxyethyl)-2,6-dimethylphenylenediamine,
4-N,N-diethyl-2-methanesulfonylaminoethyl-6-methylphenylenediamine,
4-(N-ethyl-N-2-hydroxyethyl)-2-ethoxyphenylenediamine, and
4-(N-ethyl-N-2-methoxyethyl)-2,6-dimethylphenylenediamine. As
evidenced by 4-(N-ethyl-N-2-hydroxyethyl)-2-ethoxyphenylenediamine,
in which the ethoxy substituent apparently causes sufficient
shifting of the E.sub.1/2 of the developer to allow the desired hue
shift on coupling, ortho, ortho substitution is not always
required.
[0033] Preferred cyan dye forming developers can also be
characterized in having an E.sub.1/2 at pH 11 less positive than
200 mV. The sign convention and method of measuring the
oxidation-reduction potential or E1/2 of a developer is that
described in The Theory of the Photographic Process, 4th ed., T. H.
James, ed., Macmillan, New York 1977 at pages 291 through 403, the
disclosures of which are incorporated by reference.
[0034] A specific example of a developing agent useful in the
present invention, in neutral or salt form, is represented by the
following Structure IV: 3
[0035] Preferably, at least one other color unit layer, more
preferably two other color unit layers, contains a second developer
which is also a phenylene diamine developer that, however, differs
from that of the above structures II through IV.
[0036] Some specific examples of such other developers include, but
are not limited, to N,N-diethyl-p-phenylenediamine,
4-N,N-diethyl-2-methylphe- nylenediamine,
4-(N-ethyl-N-2-methanesulfonylaminoethyl)-2-methylphenylene-
diamine, 4-(N-ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine,
4-N,N-diethyl-2-methanesulfonylaminoethylphenylenediamine,
4-(N-ethyl-N-2-methoxyethyl)-2-methylphenylenediamine,
4,5-dicyano-2-isopropylsulfonylhydrazinobenzene and
4-amino-2,6-dichlorophenol. The Theory of the Photographic Process,
4th ed., T. H. James, ed., Macmillan, New York 1977 at pages 291
through 403, the disclosures of which are incorporated by
reference, discloses some specific developers useful in the
practice of this invention. Other useful developers and developer
precursors are disclosed by Hunig et al, Angew. Chem., 70, page
215-ff (1958), by Schmidt et al, U.S. Pat. No. 2,424,256, Pelz et
al, U.S. Pat. No. 2,895,825, Wahl et al, U.S. Pat. No. 2,892,714,
Clarke et al, U.S. Pat. Nos. 5,284,739 and 5,415,981, Takeuchi et
al, U.S. Pat. No. 5,667,945, and Nabeta U.S. Pat. No. 5.723,277 the
disclosures of which are incorporated by reference.
[0037] In one embodiment, the blocked developer according to the
present invention is used in reactive association in an imaging
layer with a multifunctional coupler ("MFC"), by which is meant
that the coupler has the property of forming different color dyes
with the oxidized forms of distinct color developers. Preferably,
the same coupler can form three different colors, preferably cyan,
yellow, and magenta.
[0038] The imaging member can additionally comprise a support that
can be a reflective support or a transparent support. When
reflective, the support is generally white. When transparent, the
support is generally clear although it can be tinted. Details of
support construction are well known in the paper and photographic
arts. Particular photographic supports especially useful in this
invention, including subbing layers to enhance adhesion, are
disclosed in Research Disclosure, published by Kenneth Mason
Publications, Ltd., Dudley house, 12 North Street, Emsworth,
Hampshire P010 7DQ, England. Vol. 389, September 1996 Item 38957,
XV, Supports. In another embodiment, the member can comprise a
peelable support and an adhesion layer enabling a formed image to
be applied to an object, as for example, to form a customized
decorative item. The support can be supplied in roll or sheet form.
Alternatively, the support can be a rigid member. In one
embodiment, an imaging layer can be located on only one side of the
support. In another embodiment, imaging layers can be located on
both sides of the support to provide for double sided images, ease
of use and anti-curl properties. Stabilizers, Section X, UV
Stabilizers, and Section XI, Surfactants, the disclosures of which
are incorporated by reference.
[0039] A multifunctional dye forming coupler can be any known
coupler, or modification, variation, or derivative thereof, that
possesses the requisite property of forming different color dyes
with the oxidized forms of distinct color developers. Most
generally, such a coupler will have Structure I: 4
[0040] wherein:
[0041] C is a carbon atom at which coupling occurs;
[0042] L represents a hydrogen atom or a leaving group covalently
bound to C and which is displaced on coupling,
[0043] H is an acidic hydrogen atom serving to direct coupling to C
and which is covalently bound to C directly or by conjugation;
and
[0044] Z represents the remainder of the atoms of the coupler, in
cyclic or acyclic form which together provide sufficient electron
withdrawal to render H acidic and together provide sufficient
ballast function to render the dye formed from the coupler
immobile.
[0045] The coupler according to Structure I can be monomeric or
polymeric in nature. Some couplers useful in the practice of this
invention are described in Research Disclosure, Item 38957, Section
X, Dye Image Formers and Modifiers, in Research Disclosure, Item
37038 (1995); in Katz and Fogel, Photographic Analysis, Morgan
& Morgan, Hastings-on-Hudson, New York (1971), in the Appendix;
in Lau et al, U.S. Pat. No. 5,670,302; and in European Patent
Application EP 0,762,201 A1, the disclosures of which are all
incorporated by reference.
[0046] In a preferred embodiment, the coupler is a pyrazole,
pyrazolone, pyrazolotriazole, pyrazolotetrazole,
2-acylamino-1-naphthol or cyanoacetate coupler. Examples of such
couplers are illustrated in the references cited above. Additional
specific examples of these useful couplers are shown as structures
M-1 through M-17 of pages 82-83, and as "Coupler 3" of page 98
right column, "Coupler 4", "Coupler 5", "Coupler 8" and "Coupler 9"
of page 99, right column, "Coupler 3" of page 100, right column,
and "Coupler 4" and "Coupler 5" of page 101, left column in
Research Disclosure, Item 37038 (1995).
[0047] Some examples of preferred multifunctional dye forming
couplers include, but are not limited to, the following couplers:
567
[0048] Multifunctional dye-forming couplers useful in the invention
can be incorporated in the imaging member in any manner known in
the art. These methods include, but are not limited to,
incorporation as oil-in-water emulsions, known colloquially in the
photographic arts as "dispersions", as reverse phase emulsion, as
solid particle dispersions, as multiphase dispersions, as molecular
dispersions or "Fisher" dispersions, or as polymer loaded
dispersions or loaded latex dispersions. When the multifunctional
dye forming couplers are polymeric in nature, they can additionally
be incorporated merely by physically diluting the polymeric coupler
with vehicle. While the multifunctional dye forming coupler can be
employed in the member at any concentration that enables the
desired formation of a multicolor image, it is preferred that the
multifunctional dye forming coupler be applied to the member at
between about 50 and 3000 mg/m.sup.2. It is more preferred that the
multifunctional dye forming coupler be applied to the member at
between about 200 and 800 mg/m.sup.2.
[0049] The imaging member can further comprise an incorporated
solvent. In one embodiment, the multifunctional dye forming coupler
is provided as an emulsion in such a solvent. In this embodiment,
any of the high boiling organic solvents known in the photographic
arts as "coupler solvents" can be employed. In this situation, the
solvent acts as a manufacturing aid. Alternatively, the solvent can
be incorporated separately. In both situations, the solvent can
further function as a coupler stabilizer, a dye stabilizer, a
reactivity enhancer or moderator, or as a hue shifting agent, all
as known in the photographic arts. Additionally, auxiliary solvents
can be employed to aid dissolution of the multifunctional dye
forming coupler in the coupler solvent. Particulars of coupler
solvents and their use are described in the aforesaid mentioned
references and in Research Disclosure, Item 37038 (1995), Section
IX, Solvents, and Section XI, Surfactants, incorporated herein by
reference. Specific examples of some coupler solvents include, but
are not limited to, tritoluyl phosphate, dibutyl phthalate,
N,N-diethyldodecanamide, N,N-dibutyldodecanamide,
tris(2-ethylhexyl)phosphate, acetyl tributyl citrate,
2,4-di-tert-pentylphenol, 2-(2-butoxyethoxy)ethyl acetate and
1,4-cyclohexyldimethylene bis(2-ethylhexanoate). The choice of
coupler solvent and vehicle can influence the hue of dyes formed,
as disclosed by Merkel et al at U.S. Pat. Nos. 4,808,502 and
4,973,535. Generally, it is found that materials with a
hydrogen-bond-donating ability can shift dyes bathochromically,
while materials with a hydrogen-bond-accepting ability can shift
dyes hypsochromically. Additionally, use of materials with low
polarizability can of itself promote hypsochromic dye hue shifts as
well as promote dye aggregation. It is recognized that coupler
ballasts often enable dyes and dye-coupler mixtures to function as
self-solvents with a concomitant shift in hue. The polarizability,
and the hydrogen-bond-donating and accepting ability of various
materials are described by Kamlet et al in J. Org. Chem, 48,
2877-87 (1983), the disclosures of which are incorporated by
reference.
[0050] As indicated above, the blocked developing agent of the
present invention may be in only one color unit layer in an imaging
element.
[0051] Copending Commonly assigned U.S. Ser. No. 60/211,299 (docket
81248), hereby incorporated by reference discloses a
light-sensitive silver-halide color photographic element having a
common chromogenic coupler and a distinct developer associated with
each color forming layer unit, one of which developer may be as
disclosed herein. This application discloses a way of forming
multiple colors from a common coupler. In a first embodiment, the
light sensitive silver halide color photographic element has a
red-light-sensitive silver-halide layer unit and a first blocked
coupling developer, a green-light-sensitive silver-halide layer
unit and a second blocked coupling developer, and a
blue-light-sensitive silver-halide layer unit having a third
blocked coupling developer, wherein each layer unit has the same
chromogenic coupler.
[0052] Copending Commonly assigned U.S. Ser. No. 60/211,299 (docket
81248), hereby incorporated by reference discloses a light
sensitive color photographic imaging element comprising at least
two different chromogenic couplers including, in reactive
association, a multifunctional coupler and a developer precursor
liberating a developing agent enabling cyan color from the
multifunctional coupler on development, wherein the multifunctional
coupler has the property that it is capable of forming at least one
other distinctly colored dye with an oxidized form of the
conventional developer 4-(N-ethyl-N-2-hydroxyethyl)--
2-methylphenylenediamine. In one embodiment, the multifunctional
coupler has the property that it is capable of forming a distinctly
colored magenta dye with an oxidized form of the conventional
developer 4-(N-ethyl-N-2-hydroxyethyl)-2-methylphenylenediamine.
The latter developer (also known as "CD2"), which developer is
widely used, is used herein as a standard means for the purpose of
enabling a convenient color comparison, but other developers could
have been substituted instead.
[0053] A typical color negative film construction useful in the
practice of the invention is illustrated by the following element,
SCN-1:
1 Element SCN-1 SOC Surface Overcoat BU Blue Recording Layer Unit
IL1 First Interlayer GU Green Recording Layer Unit IL2 Second
Interlayer RU Red Recording Layer Unit AHU Antihalation Layer Unit
S Support SOC Surface Overcoat
[0054] Details of support construction are well understood in the
art. Examples of useful supports are poly(vinylacetal) film,
polystyrene film, poly(ethyleneterephthalate) film, poly(ethylene
naphthalate) film, polycarbonate film, and related films and
resinous materials, as well as paper, cloth, glass, metal, and
other supports that withstand the anticipated processing
conditions. The element can contain additional layers, such as
filter layers, interlayers, overcoat layers, subbing layers,
antihalation layers and the like. Transparent and reflective
support constructions, including subbing layers to enhance
adhesion, are disclosed in Section XV of Research Disclosure,
September 1996, Number 389, Item 38957 (hereafter referred to as
("Research Disclosure I").
[0055] The photographic elements of the invention may also usefully
include a magnetic recording material as described in Research
Disclosure, Item 34390, November 1992, or a transparent magnetic
recording layer such as a layer containing magnetic particles on
the underside of a transparent support as in U.S. Pat. No.
4,279,945, and U.S. Pat. No. 4,302,523.
[0056] Each of blue, green and red recording layer units BU, GU and
RU are formed of one or more hydrophilic colloid layers and contain
at least one radiation-sensitive silver halide emulsion, including
the developing agent and, in certain embodiments, the common dye
image-forming coupler. It is preferred that the green, and red
recording units are subdivided into at least two recording layer
sub-units to provide increased recording latitude and reduced image
granularity. In the simplest contemplated construction each of the
layer units or layer sub-units consists of a single hydrophilic
colloid layer containing emulsion and coupler. When coupler present
in a layer unit or layer sub-unit is coated in a hydrophilic
colloid layer other than an emulsion containing layer, the coupler
containing hydrophilic colloid layer is positioned to receive
oxidized color developing agent from the emulsion during
development. In this case, the coupler containing layer is usually
the next adjacent hydrophilic colloid layer to the emulsion
containing layer.
[0057] In order to ensure excellent image sharpness, and to
facilitate manufacture and use in cameras, all of the sensitized
layers are preferably positioned on a common face of the support.
When in spool form, the element will be spooled such that when
unspooled in a camera, exposing light strikes all of the sensitized
layers before striking the face of the support carrying these
layers. Further, to ensure excellent sharpness of images exposed
onto the element, the total thickness of the layer units above the
support should be controlled. Generally, the total thickness of the
sensitized layers, interlayers and protective layers on the
exposure face of the support are less than 35 .mu.m. In another
embodiment, sensitized layers disposed on two sides of a support,
as in a duplitized film, can be employed.
[0058] In a preferred embodiment of this invention, the processed
photographic film contains only limited amounts of color masking
couplers, incorporated permanent Dmin adjusting dyes and
incorporated permanent antihalation dyes. Generally, such films
contain color masking couplers in total amounts up to about 0.6
mmol/m.sup.2, preferably in amounts up to about 0.2 mmol/m.sup.2,
more preferably in amounts up to about 0.05 mmol/m.sup.2, and most
preferably in amounts up to about 0.01 mmol/m.sup.2.
[0059] The incorporated permanent Dmin adjusting dyes are generally
present in total amounts up to about 0.2 mmol/m.sup.2, preferably
in amounts up to about 0.1 mmol/m.sup.2, more preferably in amounts
up to about 0.02 mmol/m.sup.2, and most preferably in amounts up to
about 0.005 mmol/m.sup.2.
[0060] The incorporated permanent antihalation density is up to
about 0.6 in blue, green or red density, more preferably up to
about 0.3 in blue, green or red density, even more preferably up to
about 0.1 in blue, green or red density and most preferably up to
about 0.05 in blue, green or red Status M density.
[0061] Limiting the amount of color masking couplers, permanent
antihalation density and incorporated permanent Dmin adjusting dyes
serves to reduce the optical density of the films, after
processing, in the 350 to 750 nm range, and thus improves the
subsequent scanning and digitization of the imagewise exposed and
processed films.
[0062] Overall, the limited Dmin and tone scale density enabled by
controlling the quantity of incorporated color masking couplers,
incorporated permanent Dmin adjusting dyes and antihalation and
support optical density can serve to both limit scanning noise
(which increases at high optical densities), and to improve the
overall signal-to-noise characteristics of the film to be scanned.
Relying on the digital correction step to provide color correction
obviates the need for color masking couplers in the films.
[0063] Any convenient selection from among conventional
radiation-sensitive silver halide emulsions can be incorporated
within the layer units and used to provide the spectral
absorptances of the invention. Most commonly high bromide emulsions
containing a minor amount of iodide are employed. To realize higher
rates of processing, high chloride emulsions can be employed.
Radiation-sensitive silver chloride, silver bromide, silver
iodobromide, silver iodochloride, silver chlorobromide, silver
bromochloride, silver iodochlorobromide and silver
iodobromochloride grains are all contemplated. The grains can be
either regular or irregular (e.g., tabular). Tabular grain
emulsions, those in which tabular grains account for at least 50
(preferably at least 70 and optimally at least 90) percent of total
grain projected area are particularly advantageous for increasing
speed in relation to granularity. To be considered tabular a grain
requires two major parallel faces with a ratio of its equivalent
circular diameter (ECD) to its thickness of at least 2.
Specifically preferred tabular grain emulsions are those having a
tabular grain average aspect ratio of at least 5 and, optimally,
greater than 8. Preferred mean tabular grain thicknesses are less
than 0.3 .mu.m (most preferably less than 0.2 .mu.m). Ultrathin
tabular grain emulsions, those with mean tabular grain thicknesses
of less than 0.07 .mu.m, are specifically contemplated. However, in
a preferred embodiment, a preponderance low reflectivity grains are
preferred. By preponderance is meant that greater than 50% of the
grain projected area is provided by low reflectivity silver halide
grains. It is even more preferred that greater than 70% of the
grain projected area be provided by low reflectivity silver halide
grains. Low reflective silver halide grains are those having an
average grain having a grain thickness>0.06, preferably
>0.08, and more preferable >0-10 microns. The grains
preferably form surface latent images so that they produce negative
images when processed in a surface developer in color negative film
forms of the invention.
[0064] Illustrations of conventional radiation-sensitive silver
halide emulsions are provided by Research Disclosure I, cited
above, I. Emulsion grains and their preparation. Chemical
sensitization of the emulsions, which can take any conventional
form, is illustrated in section IV. Chemical sensitization.
Compounds useful as chemical sensitizers, include, for example,
active gelatin, sulfur, selenium, tellurium, gold, platinum,
palladium, iridium, osmium, rhenium, phosphorous, or combinations
thereof Chemical sensitization is generally carried out at pAg
levels of from 5 to 10, pH levels of from 4 to 8, and temperatures
of from 30 to 80.degree. C. Spectral sensitization and sensitizing
dyes, which can take any conventional form, are illustrated by
section V. Spectral sensitization and desensitization. The dye may
be added to an emulsion of the silver halide grains and a
hydrophilic colloid at any time prior to (e.g., during or after
chemical sensitization) or simultaneous with the coating of the
emulsion on a photographic element. The dyes may, for example, be
added as a solution in water or an alcohol or as a dispersion of
solid particles. The emulsion layers also typically include one or
more antifoggants or stabilizers, which can take any conventional
form, as illustrated by section VII. Antifoggants and
stabilizers.
[0065] The silver halide grains to be used in the invention may be
prepared according to methods known in the art, such as those
described in Research Disclosure I, cited above, and James, The
Theory of the Photographic Process. These include methods such as
ammoniacal emulsion making, neutral or acidic emulsion making, and
others known in the art. These methods generally involve mixing a
water soluble silver salt with a water soluble halide salt in the
presence of a protective colloid, and controlling the temperature,
pAg, pH values, etc, at suitable values during formation of the
silver halide by precipitation.
[0066] In the course of grain precipitation, one or more dopants
(grain occlusions other than silver and halide) can be introduced
to modify grain properties. For example, any of the various
conventional dopants disclosed in Research Disclosure I, Section 1.
Emulsion grains and their preparation, sub-section G. Grain
modifying conditions and adjustments, paragraphs (3), (4) and (5),
can be present in the emulsions of the invention. In addition it is
specifically contemplated to dope the grains with transition metal
hexacoordination complexes containing one or more organic ligands,
as taught by Olm, et al, U.S. Pat. No. 5,360,712, the disclosure of
which is here incorporated by reference.
[0067] It is specifically contemplated to incorporate in the face
centered cubic crystal lattice of the grains a dopant capable of
increasing imaging speed by forming a shallow electron trap
(hereinafter also referred to as a SET) as discussed in Research
Disclosure Item 36736 published November 1994, here incorporated by
reference.
[0068] The photographic elements of the present invention, as is
typical, provide the silver halide in the form of an emulsion.
Photographic emulsions generally include a vehicle for coating the
emulsion as a layer of a photographic element. Useful vehicles
include both naturally occurring substances such as proteins,
protein derivatives, cellulose derivatives (e.g., cellulose
esters), gelatin (e.g., alkali-treated gelatin such as cattle bone
or hide gelatin, or acid treated gelatin such as pigskin gelatin),
deionized gelatin, gelatin derivatives (e.g., acetylated gelatin,
phthalated gelatin, and the like), and others as described in
Research Disclosure, I. Also useful as vehicles or vehicle
extenders are hydrophilic water-permeable colloids. These include
synthetic polymeric peptizers, carriers, and/or binders such as
poly(vinyl alcohol), poly(vinyl lactams), acrylamide polymers,
polyvinyl acetals, polymers of alkyl and sulfoalkyl acrylates and
methacrylates, hydrolyzed polyvinyl acetates, polyamides, polyvinyl
pyridine, methacrylamide copolymers. The vehicle can be present in
the emulsion in any amount useful in photographic emulsions. The
emulsion can also include any of the addenda known to be useful in
photographic emulsions.
[0069] While any useful quantity of light sensitive silver, as
silver halide, can be employed in the elements useful in this
invention, it is preferred that the total quantity be not more than
4.5 g/m.sup.2 of silver, preferably less. Silver quantities of less
than 4.0 g/m.sup.2 are preferred, and silver quantities of less
than 3.5 g/m.sup.2 are even more preferred. The lower quantities of
silver improve the optics of the elements, thus enabling the
production of sharper pictures using the elements. These lower
quantities of silver are additionally important in that they enable
rapid development and desilvering of the elements. Conversely, a
silver coating coverage of at least 1.0 g of coated silver per
m.sup.2 of support surface area in the element is necessary to
realize an exposure latitude of at least 2.7 log E while
maintaining an adequately low graininess position for pictures
intended to be enlarged. Silver coverages in excess of 1.5
g/m.sup.2 are preferred while silver coverages in excess of 2.5
g/m.sup.2 are more preferred.
[0070] It is common practice to coat one, two or three separate
emulsion layers within a single dye image-forming layer unit. When
two or more emulsion layers are coated in a single layer unit, they
are typically chosen to differ in sensitivity. When a more
sensitive emulsion is coated over a less sensitive emulsion, a
higher speed is realized than when the two emulsions are blended.
When a less sensitive emulsion is coated over a more sensitive
emulsion, a higher contrast is realized than when the two emulsions
are blended. It is preferred that the most sensitive emulsion be
located nearest the source of exposing radiation and the slowest
emulsion be located nearest the support.
[0071] One or more of the layer units of the invention is
preferably subdivided into at least two, and more preferably three
or more sub-unit layers. It is preferred that all light sensitive
silver halide emulsions in the color recording unit have spectral
sensitivity in the same region of the visible spectrum. In this
embodiment, while all silver halide emulsions incorporated in the
unit have spectral absorptance according to invention, it is
expected that there are minor differences in spectral absorptance
properties between them. In still more preferred embodiments, the
sensitizations of the slower silver halide emulsions are
specifically tailored to account for the light shielding effects of
the faster silver halide emulsions of the layer unit that reside
above them, in order to provide an imagewise uniform spectral
response by the photographic recording material as exposure varies
with low to high light levels. Thus higher proportions of peak
light absorbing spectral sensitizing dyes may be desirable in the
slower emulsions of the subdivided layer unit to account for
on-peak shielding and broadening of the underlying layer spectral
sensitivity.
[0072] The interlayers IL1 and IL2 are hydrophilic colloid layers
having as their primary function color contamination
reduction-i.e., prevention of oxidized developing agent from
migrating to an adjacent recording layer unit before reacting with
dye-forming coupler. The interlayers are in pall effective simply
by increasing the diffusion path length that oxidized developing
agent must travel. To increase the effectiveness of the interlayers
to intercept oxidized developing agent, it is conventional practice
to incorporate oxidized developing agent. Antistain agents
(oxidized developing agent scavengers) can be selected from among
those disclosed by Research Disclosure I, X. Dye image formers and
modifiers, D. Hue modifiers/stabilization, paragraph (2). When one
or more silver halide emulsions in GU and RU are high bromide
emulsions and, hence have significant native sensitivity to blue
light, it is preferred to incorporate a yellow filter, such as
Carey Lea silver or a yellow processing solution decolorizable dye,
in IL1. Suitable yellow filter dyes can be selected from among
those illustrated by Research Disclosure I, Section VIII. Absorbing
and scattering materials, B. Absorbing materials. In elements of
the instant invention, magenta colored filter materials are absent
from IL2 and RU.
[0073] The antihalation layer unit AHU typically contains a
processing solution removable or decolorizable light absorbing
material, such as one or a combination of pigments and dyes.
Suitable materials can be selected from among those disclosed in
Research Disclosure I, Section VIII. Absorbing materials. A common
alternative location for AHU is between the support S and the
recording layer unit coated nearest the support.
[0074] The surface overcoats SOC are hydrophilic colloid layers
that are provided for physical protection of the color negative
elements during handling and processing. Each SOC also provides a
convenient location for incorporation of addenda that are most
effective at or near the surface of the color negative element. In
some instances the surface overcoat is divided into a surface layer
and an interlayer, the latter functioning as spacer between the
addenda in the surface layer and the adjacent recording layer unit.
In another common variant form, addenda are distributed between the
surface layer and the interlayer, with the latter containing
addenda that are compatible with the adjacent recording layer unit.
Most typically the SOC contains addenda, such as coating aids,
plasticizers and lubricants, antistats and matting agents, such as
illustrated by Research Disclosure I, Section IX. Coating physical
property modifying addenda. The SOC overlying the emulsion layers
additionally preferably contains an ultraviolet absorber, such as
illustrated by Research Disclosure I, Section VI. UV dyes/optical
brighteners/luminescent dyes, paragraph (1).
[0075] Instead of the layer unit sequence of element SCN-1,
alternative layer units sequences can be employed and are
particularly attractive for some emulsion choices. Using high
chloride emulsions and/or thin (<0.2 .mu.m mean grain thickness)
tabular grain emulsions all possible interchanges of the positions
of BU, GU and RU can be undertaken without risk of blue light
contamination of the minus blue records, since these emulsions
exhibit negligible native sensitivity in the visible spectrum. For
the same reason, it is unnecessary to incorporate blue light
absorbers in the interlayers.
[0076] When the emulsion layers within a dye image-forming layer
unit differ in speed, it is conventional practice to limit the
incorporation of dye image-forming coupler in the layer of highest
speed to less than a stoichiometric amount, based on silver. The
function of the highest speed emulsion layer is to create the
portion of the characteristic curve just above the minimum
density-i.e., in an exposure region that is below the threshold
sensitivity of the remaining emulsion layer or layers in the layer
unit. In this way, adding the increased granularity of the highest
sensitivity speed emulsion layer to the dye image record produced
is minimized without sacrificing imaging speed.
[0077] In the foregoing discussion the blue, green and red
recording layer units are described as containing developing agents
for producing yellow, magenta and cyan dyes, respectively, as is
conventional practice in color negative elements used for printing.
The invention can be suitably applied to conventional color
negative construction as illustrated. Color reversal film
construction would take a similar form, with the exception that
colored masking couplers would be completely absent; in typical
forms, development inhibitor releasing couplers would also be
absent. In preferred embodiments, the color negative elements are
intended exclusively for scanning to produce three separate
electronic color records. Thus the actual hue of the image dye
produced is of no importance. What is essential is merely that the
dye image produced in each of the layer units be differentiable
from that produced by each of the remaining layer units. To provide
this capability of differentiation it is contemplated that each of
the layer units contain one or more dye image-forming couplers
chosen to produce image dye having an absorption half-peak
bandwidth lying in a different spectral region. It is immaterial
whether the blue, green or red recording layer unit forms a yellow,
magenta or cyan dye having an absorption half peak bandwidth in the
blue, green or red region of the spectrum, as is conventional in a
color negative element intended for use in printing, so long as the
absorption half-peak bandwidths of the image dye in the layer units
extend over substantially non-coextensive wavelength ranges. The
term "substantially non-coextensive wavelength ranges" means that
each image dye exhibits an absorption half-peak band width that
extends over at least a 25 nm (preferably 50 nm) spectral region
that is not occupied by an absorption half-peak band width of
another image dye. Ideally the image dyes exhibit absorption
half-peak band widths that are mutually exclusive.
[0078] When a layer unit contains two or more emulsion layers
differing in speed, it is possible to lower image granularity in
the image to be viewed, recreated from an electronic record, by
forming in each emulsion layer of the layer unit a dye image which
exhibits an absorption half-peak band width that lies in a
different spectral region than the dye images of the other emulsion
layers of layer unit. This technique is particularly well suited to
elements in which the layer units are divided into sub-units that
differ in speed. This allows multiple electronic records to be
created for each layer unit, corresponding to the differing dye
images formed by the emulsion layers of the same spectral
sensitivity. The digital record formed by scanning the dye image
formed by an emulsion layer of the highest speed is used to
recreate the portion of the dye image to be viewed lying just above
minimum density. At higher exposure levels second and, optionally,
third electronic records can be formed by scanning spectrally
differentiated dye images formed by the remaining emulsion layer or
layers. These digital records contain less noise (lower
granularity) and can be used in recreating the image to be viewed
over exposure ranges above the threshold exposure level of the
slower emulsion layers. This technique for lowering granularity is
disclosed in greater detail by Sutton U.S. Pat. No. 5,314,794, the
disclosure of which is here incorporated by reference.
[0079] Each layer unit of the color negative elements of the
invention produces a dye image characteristic curve gamma of less
than 1.5, which facilitates obtaining an exposure latitude of at
least 2.7 log E. A minimum acceptable exposure latitude of a
multicolor photographic element is that which allows accurately
recording the most extreme whites (e.g., a bride's wedding gown)
and the most extreme blacks (e.g., a bride groom's tuxedo) that are
likely to arise in photographic use. An exposure latitude of 2.6
log E can just accommodate the typical bride and groom wedding
scene. An exposure latitude of at least 3.0 log E is preferred,
since this allows for a comfortable margin of error in exposure
level selection by a photographer. Even larger exposure latitudes
are specifically preferred, since the ability to obtain accurate
image reproduction with larger exposure errors is realized. Whereas
in color negative elements intended for printing, the visual
attractiveness of the printed scene is often lost when gamma is
exceptionally low, when color negative elements are scanned to
create digital dye image records, contrast can be increased by
adjustment of the electronic signal information. When the elements
of the invention are scanned using a reflected beam, the beam
travels through the layer units twice. This effectively doubles
gamma (.DELTA.D.div..DELTA.log E) by doubling changes in density
(.DELTA.D). Thus, gamma's as low as 1.0 or even 0.6 are
contemplated and exposure latitudes of up to about 5.0 log E or
higher are feasible. Gammas above 0.25 are preferred and gammas
above 0.30 are more preferred. Gammas of between about 0.4 and 0.5
are especially preferred.
[0080] In a preferred embodiment the dye image is formed by the use
of an incorporated developing agent, in reactive association with
each color layer. More preferably, the incorporated developing
agent is a blocked developing agent.
[0081] Examples of blocked developers that can be used in
photographic elements of the present invention include, but are not
limited to, the blocked developing agents described in U.S. Pat.
No. 3,342,599, to Reeves; Research Disclosure (129 (1975) pp.
27-30) published by Kenneth Mason Publications, Ltd., Dudley Annex,
12a North Street, Emsworth, Hampshire P010 7DQ, ENGLAND; U.S. Pat.
No. 4,157,915, to Hamaoka et al.; U.S. Pat. No. 4,060,418, to
Waxman and Mourning; and in U.S. Pat. No. 5,019,492. Other examples
of blocked developers that can be used in photographic elements of
the present invention include, but are not limited to, the blocked
developing agents described in U.S. Pat. No. 3,342,599, to Reeves;
Research Disclosure (129 (1975) pp. 27-30) published by Kenneth
Mason Publications, Ltd., Dudley Annex, 12a North Street, Emsworth,
Hampshire P010 7DQ, ENGLAND; U.S. Pat. No. 4,157,915, to Hamaoka et
al.; U.S. Pat. No. 4, 060,418, to Waxman and Mourning; and in U.S.
Pat. No. 5,019,492. Particularly useful are those blocked
developers described in U.S. application Ser. No. 09/476,234, filed
Dec. 30, 1999, IMAGING ELEMENT CONTAINING A BLOCKED PHOTOGRAPICALLY
USEFUL COMPOUND; U.S. application Ser. No. 09/475,691, filed Dec.
30, 1999, IMAGING ELEMENT CONTAINING A BLOCKED PHOTOGRAPHICALLY
USEFUL COMPOUND, U.S. application Ser. No. 09/475,703, filed Dec.
30, 1999, IMAGING ELEMENT CONTAINING A BLOCKED PHOTOGRAPHICALLY
USEFUL COMPOUND; U.S. application Ser. No. 09/475,690, filed Dec.
30, 1999, IMAGING ELEMENT CONTAINING A BLOCKED PHOTOGRAPHICALLY
USEFUL COMPOUND; and U.S. application Ser. No. 09/476,233, filed
Dec. 30, 1999, PHOTOGRAPHIC OR PHOTOTHERMOGRAPHIC ELEMENT
CONTAINING A BLOCKED PHOTOGRAPHICALLY USEFUL COMPOUND. In one
embodiment of the invention, the blocked developer may be
respresented by the following Structure I:
DEV-(LINK 1).sub.1-(TIME).sub.m-(LINK 2).sub.n-B I
[0082] wherein,
[0083] DEV is a silver-halide color developing agent;
[0084] LINK 1 and LINK 2 are linking groups;
[0085] TIME is a timing group;
[0086] 1 is 0 or 1;
[0087] m is 0, 1, or2;
[0088] n is 0 or 1;
[0089] 1+n is 1 or 2;
[0090] B is a blocking group or B is:
-B'-(LINK 2).sub.n-(TIME).sub.m-(LINK 1).sub.1-DEV
[0091] wherein B' also blocks a second developing agent DEV.
[0092] In a preferred embodiment of the invention, LINK 1 or LINK 2
are of structure II: 8
[0093] wherein
[0094] X represents carbon or sulfur;
[0095] Y represents oxygen, sulfur of N--R.sub.1, where R.sub.1 is
substituted or unsubstituted alkyl or substituted or unsubstituted
aryl;
[0096] p is 1 or 2,
[0097] Z represents carbon, oxygen or sulfur;
[0098] r is 0 or 1;
[0099] with the proviso that when X is carbon, both p and r are 1,
when X is sulfur, Y is oxygen, p is 2 and r is 0;
[0100] # denotes the bond to PUG (for LINK 1) or TIME (for LINK
2):
[0101] $ denotes the bond to TIME (for LINK 1) or T.sub.(t)
substituted carbon (for LINK 2).
[0102] Illustrative linking groups include, for example, 9
[0103] TIME is a timing group. Such groups are well-known in the
art such as (1) groups utilizing an aromatic nucleophilic
substitution reaction as disclosed in U.S. Pat. No. 5,262,291, (2)
groups utilizing the cleavage reaction of a hemiacetal (U.S. Pat.
No. 4,146,396, Japanese Applications 60-249148; 60-249149); (3)
groups utilizing an electron transfer reaction along a conjugated
system (U.S. Pat. Nos. 4,409,323, 4,421,845; Japanese Applications
57-188035; 58-98728; 58-209736; 58-209738); and (4) groups using an
intramolecular nucleophilic substitution reaction (U.S. Pat. No.
4,248,962).
[0104] Illustrative timing groups are illustrated by formulae T-1
through T-4. 10
[0105] wherein:
[0106] Nu is a nucleophilic group;
[0107] E is an electrophilic group comprising one or more carbo- or
hetero-aromatic rings, containing an electron deficient carbon
atom,
[0108] LINK 3 is a linking group that provides 1 to 5 atoms in the
direct path between the nucleopnilic site of Nu and the electron
deficient carbon atom in E; and
[0109] a is 0 or 1.
[0110] Such timing groups include, for example: 11
[0111] These timing groups are described more fully in U.S. Pat.
No. 5,262,291, incorporated herein by reference. 12
[0112] wherein
[0113] V represents an oxygen atom, a sulfur atom, or an 13
[0114] R.sub.13 and R.sub.14 each represents a hydrogen atom or a
substituent group;
[0115] R.sub.15 represents a substituent group, and b represents 1
or 2.
[0116] Typical examples of R.sub.13 and R.sub.14, when they
represent substituent groups, and R.sub.15 include
[0117] R.sub.16--, R.sub.17CO--, R.sub.17SO.sub.2--, 14
[0118] where, R.sub.16 represents an aliphatic or aromatic
hydrocarbon residue, or a heterocyclic group; and R.sub.17
represents a hydrogen atom, an aliphatic or aromatic hydrocarbon
residue, or a heterocyclic group, R.sub.13, R.sub.14 and R.sub.15
each may represent a divalent group, and any two of them combine
with each other to complete a ring structure. Specific examples of
the group represented by formula (T-2) are illustrated below.
15
[0119] wherein Nu 1 represents a nucleophilic group, and an oxygen
or sulfur atom can be given as an example of nucleophilic species;
E1 represents an electrophilic group being a group which is
subjected to nucleophilic attack by Nu 1; and LINK 4 represents a
linking group which enables Nu 1 and E1 to have a steric
arrangement such that an intramolecular nucleophilic substitution
reaction can occur. Specific examples of the group represented by
formula (T-3) are illustrated below. 16
[0120] wherein V, R.sub.13, R.sub.14 and b all have the same
meaning as in formula (T-2), respectively. In addition, R.sub.13
and R.sub.14 may be joined together to form a benzene ring or a
heterocyclic ring, or V may be joined with R.sub.13 or R.sub.14 to
form a benzene or heterocyclic ring. Z.sub.1 and Z.sub.2 each
independently represents a carbon atom or a nitrogen atom, and x
and y each represents 0 or 1.
[0121] Specific examples of the timing group (T-4) are illustrated
below. 17
[0122] The following are merely some examples of photographically
useful blocked developers that may be used according to the present
invention. 181920
[0123] A number of modifications of color negative elements have
been suggested for accommodating scanning, as illustrated by
Research Disclosure I, Section XIV, Scan facilitating features.
These systems to the extent compatible with the color negative
element constructions described above are contemplated for use in
the practice of this invention.
[0124] It is also contemplated that the imaging element of this
invention may be used with non-conventional sensitization schemes.
For example, instead of using imaging layers sensitized to the red,
green, and blue regions of the spectrum, the light-sensitive
material may have one white-sensitive layer to record scene
luminance, and two color-sensitive layers to record scene
chrominance. Following development, the resulting image can be
scanned and digitally reprocessed to reconstruct the full colors of
the original scene as described in U.S. Pat. No. 5,962,205. The
imaging element may also comprise a pan-sensitized emulsion with
accompanying color-separation exposure. In this embodiment, the
developers of the invention would give rise to a colored or neutral
image that, in conjunction with the separation exposure, would
enable full recovery of the original scene color values. In such an
element, the image may be formed by either developed silver
density, a combination of one or more conventional couplers, or
"black" couplers such as resorcinol couplers. The separation
exposure may be made either sequentially through appropriate
filters, or simultaneously through a system of spatially discreet
filter elements (commonly called a "color filter array").
[0125] The imaging element of the invention may also be a black and
white image-forming material comprised, for example, of a
pan-sensitized silver halide emulsion and a developer of the
invention. In this embodiment, the image may be formed by developed
silver density following processing, or by a coupler that generates
a dye which can be used to carry the neutral image tone scale.
[0126] When conventional yellow, magenta, and cyan image dyes are
formed to read out the recorded scene exposures following chemical
development of conventional exposed color photographic materials,
the response of the red, green, and blue color recording units of
the element can be accurately discerned by examining their
densities. Densitometry is the measurement of transmitted light by
a sample using selected colored filters to separate the imagewise
response of the RGB image dye forming units into relatively
independent channels. It is common to use Status M filters to gauge
the response of color negative film elements intended for optical
printing, and Status A filters for color reversal films intended
for direct transmission viewing. In integral densitometry, the
unwanted side and tail absorptions of the imperfect image dyes
leads to a small amount of channel mixing, where part of the total
response of, for example, a magenta channel may come from off-peak
absorptions of either the yellow or cyan image dyes records, or
both, in neutral characteristic curves. Such artifacts may be
negligible in the measurement of a film's spectral sensitivity. By
appropriate mathematical treatment of the integral density
response, these unwanted off-peak density contributions can be
completely corrected providing analytical densities, where the
response of a given color record is independent of the spectral
contributions of the other image dyes. Analytical density
determination has been summarized in the SPSE Handbook of
Photographic Science and Engineering, W. Thomas, editor, John Wiley
and Sons, New York, 1973, Section 15.3, Color Densitometry, pp.
840-848.
[0127] Image noise can be reduced, where the images are obtained by
scanning exposed and processed color negative film elements to
obtain a manipulatable electronic record of the image pattern,
followed by reconversion of the adjusted electronic record to a
viewable form. Image sharpness and colorfulness can be increased by
designing layer gamma ratios to be within a narrow range while
avoiding or minimizing other performance deficiencies, where the
color record is placed in an electronic form prior to recreating a
color image to be viewed. Whereas it is impossible to separate
image noise from the remainder of the image information, either in
printing or by manipulating an electronic image record, it is
possible by adjusting an electronic image record that exhibits low
noise, as is provided by color negative film elements with low
gamma ratios, to improve overall curve shape and sharpness
characteristics in a manner that is impossible to achieve by known
printing techniques. Thus, images can be recreated from electronic
image records derived from such color negative elements that are
superior to those similarly derived from conventional color
negative elements constructed to serve optical printing
applications. The excellent imaging characteristics of the
described element are obtained when the gamma ratio for each of the
red, green and blue color recording units is less than 1.2. In a
more preferred embodiment, the red, green, and blue light sensitive
color forming units each exhibit gamma ratios of less than 1. 15.
In an even more preferred embodiment, the red and blue light
sensitive color forming units each exhibit gamma ratios of less
than 1.10. In a most preferred embodiment, the red, green, and blue
light sensitive color forming units each exhibit gamma ratios of
less than 1.10. In all cases, it is preferred that the individual
color unit(s) exhibit gamma ratios of less than 1.15, more
preferred that they exhibit gamma ratios of less than 1.10 and even
more preferred that they exhibit gamma ratios of less than 1.05. In
a like vein, it is preferred that the gamma ratios be greater than
0.8, more preferred that they be greater than 0.85 and most
preferred that they be greater than 0.9. The gamma ratios of the
layer units need not be equal. These low values of the gamma ratio
are indicative of low levels of interlayer interaction, also known
as interlayer interimage effects, between the layer units and are
believed to account for the improved quality of the images after
scanning and electronic manipulation. The apparently deleterious
image characteristics that result from chemical interactions
between the layer units need not be electronically suppressed
during the image manipulation activity. The interactions are often
difficult if not impossible to suppress properly using known
electronic image manipulation schemes.
[0128] Elements having excellent light sensitivity are best
employed in the practice of this invention. The elements should
have a sensitivity of at least about ISO 50, preferably have a
sensitivity of at least about ISO 100, and more preferably have a
sensitivity of at least about ISO 200. Elements having a
sensitivity of up to ISO 3200 or even higher are specifically
contemplated. The speed, or sensitivity, of a color negative
photographic element is inversely related to the exposure required
to enable the attainment of a specified density above fog after
processing. Photographic speed for a color negative element with a
gamma of about 0.65 in each color record has been specifically
defined by the American National Standards Institute (ANSI) as ANSI
Standard Number PH 2.27-1981 (ISO (ASA Speed)) and relates
specifically the average of exposure levels required to produce a
density of 0.15 above the minimum density in each of the green
light sensitive and least sensitive color recording unit of a color
film. This definition conforms to the International Standards
Organization (ISO) film speed rating. For the purposes of this
application, if the color unit gammas differ from 0.65, the ASA or
ISO speed is to be calculated by linearly amplifying or
deamplifying the gamma vs. log E (exposure) curve to a value of
0.65 before determining the speed in the otherwise defined
manner.
[0129] The present invention also contemplates the use of
photographic (including photothermographic) elements of the present
invention in what are often referred to as single use cameras (or
"film with lens" units). These cameras are sold with film preloaded
in them and the entire camera is returned to a processor with the
exposed film remaining inside the camera. The one-time-use cameras
employed in this invention can be any of those known in the art.
These cameras can provide specific features as known in the art
such as shutter means, film winding means, film advance means,
waterproof housings, single or multiple lenses, lens selection
means, variable aperture, focus or focal length lenses, means for
monitoring lighting conditions, means for adjusting shutter times
or lens characteristics based on lighting conditions or user
provided instructions, and means for camera recording use
conditions directly on the film. These features include, but are
not limited to: providing simplified mechanisms for manually or
automatically advancing film and resetting shutters as described at
Skarman, U.S. Pat. No. 4,226,517; providing apparatus for automatic
exposure control as described at Matterson et al, U.S. Pat. No.
4,345,835; moisture-proofing as described at Fujimura et al, U.S.
Pat. No. 4,766,451; providing internal and external film casings as
described at Ohmura et al, U.S. Pat. No. 4,751,536; providing means
for recording use conditions on the film as described at Taniguchi
et al, U.S. Pat. No. 4,780,735, providing lens fitted cameras as
described at Arai, U.S. Pat. No. 4,804,987; providing film supports
with superior anti-curl properties as described at Sasaki et al,
U.S. Pat. No. 4,827,298; providing a viewfinder as described at
Ohmura et al, U.S. Pat. No. 4,812,863; providing a lens of defined
focal length and lens speed as described at Ushiro et al, U.S. Pat.
No. 4,812,866; providing multiple film containers as described at
Nakayama et al, U.S. Pat. No. 4,831,398 and at Ohmura et al, U.S.
Pat. No. 4,833,495; providing films with improved anti-friction
characteristics as described at Shiba, U.S. Pat. No. 4,866,469;
providing winding mechanisms, rotating spools, or resilient sleeves
as described at Mochida, U.S. Pat. No. 4,884,087; providing a film
patrone or cartridge removable in an axial direction as described
by Takei et al at U.S. Pat. Nos. 4,890,130 and 5,063,400; providing
an electronic flash means as described at Ohmura et al, U.S. Pat.
No. 4,896,178; providing an externally operable member for
effecting exposure as described at Mochida et al, U.S. Pat. No.
4,954,857; providing film support with modified sprocket holes and
means for advancing said film as described at Murakami, U.S. Pat.
No. 5,049,908, providing internal mirrors as described at Hara,
U.S. Pat. No. 5,084,719; and providing silver halide emulsions
suitable for use on tightly wound spools as described at Yagi et
al, European Patent Application 0,466,417 A.
[0130] While the film may be mounted in the one-time-use camera in
any manner known in the art, it is especially preferred to mount
the film in the one-time-use camera such that it is taken up on
exposure by a thrust cartridge. Thrust cartridges are disclosed by
Kataoka et al U.S. Pat. No. 5,226,613, by Zander U.S. Pat. No.
5,200,777; by Dowling et al U.S. Pat. No. 5,031,852; and by
Robertson et al U.S. Pat. No. 4,834,306. Narrow bodied one-time-use
cameras suitable for employing thrust cartridges in this way are
described by Tobioka et al U.S. Pat. No. 5,692,221.
[0131] Cameras may contain a built-in processing capability, for
example a heating element. Designs for such cameras including their
use in an image capture and display system are disclosed in Stoebe,
et al., U.S. patent application Ser. No. 09/388,573 filed Sep. 1,
1999, incorporated herein by reference. The use of a one-time use
camera as disclosed in said application is particularly preferred
in the practice of this invention.
[0132] Photographic elements of the present invention are
preferably imagewise exposed using any of the known techniques,
including those described in Research Disclosure I, Section XVI.
This typically involves exposure to light in the visible region of
the spectrum, and typically such exposure is of a live image
through a lens, although exposure can also be exposure to a stored
image (such as a computer stored image) by means of light emitting
devices (such as light emitting diodes, CRT and the like). The
photothermographic elements are also exposed by means of various
forms of energy, including ultraviolet and infrared regions of the
electromagnetic spectrum as well as electron beam and beta
radiation, gamma ray, x-ray, alpha particle, neutron radiation and
other forms of corpuscular wave-like radiant energy in either
non-coherent (random phase) or coherent (in phase) forms produced
by lasers. Exposures are monochromatic, orthochromatic, or
panchromatic depending upon the spectral sensitization of the
photographic silver halide.
[0133] The elements as discussed above may serve as origination
material for some or all of the following process steps: image
scanning to produce an electronic rendition of the capture image,
and subsequent digital processing of that rendition to manipulate,
store, transmit, output, or display electronically that image.
[0134] As mentioned above, the photographic elements of the present
invention can be photothermographic elements, for example of the
type described in Research Disclosure, June 1978, Item No. 17029
(hereafter "Research Disclosure I") are included by reference, and
as also described in more recent patents in the photothermographic
field. The photothermographic elements may be of the type A or type
B disclosed in Research Disclosure I. Type A elements contain in
reactive association a photosensitive silver halide, a reducing
agent or developer, an activator, and a coating vehicle or binder.
In these systems development occurs by reduction of silver ions in
the photosensitive silver halide to metallic silver. Type B systems
can contain all of the elements of a type A system in addition to a
salt or complex of an organic compound with silver ion. In these
systems, this organic complex is reduced during development to
yield silver metal. The organic silver salt will be referred to as
the silver donor. References describing such imaging elements
include, for example, U.S. Pat. Nos. 3,457,075; 4,459,350,
4,264,725 and 4,741,992.
[0135] A photothermographic element comprises a photosensitive
component that consists essentially of photographic silver halide.
In the type B photothermographic material it is believed that the
latent image silver from the silver halide acts as a catalyst for
the described image-forming combination upon processing. In these
systems, a preferred concentration of photographic silver halide is
within the range of 0.01 to 100 moles of photographic silver halide
per mole of silver donor in the photothermographic material.
[0136] The Type B photothermographic element comprises an
oxidation-reduction image forming combination that contains an
organic silver salt oxidizing agent. The organic silver salt is a
silver salt which is comparatively stable to light, but aids in the
formation of a silver image when heated to 80.degree. C. or higher
in the presence of an exposed photocatalyst (i.e., the
photosensitive silver halide) and a reducing agent.
[0137] Suitable organic silver salts include silver salts of
organic compounds having a carboxyl group. Preferred examples
thereof include a silver salt of an aliphatic carboxylic acid and a
silver salt of an aromatic carboxylic acid. Preferred examples of
the silver salts of aliphatic carboxylic acids include silver
behenate, silver stearate, silver oleate, silver laureate, silver
caprate, silver myristate, silver palmitate, silver maleate, silver
fumarate, silver tartarate, silver furoate, silver linoleate,
silver butyrate and silver camphorate, mixtures thereof, etc.
Silver salts which are substitutable with a halogen atom or a
hydroxyl group can also be effectively used. Preferred examples of
the silver salts of aromatic carboxylic acid and other carboxyl
group-containing compounds include silver benzoate, a
silver-substituted benzoate such as silver 3,5-dihydroxybenzoate,
silver o-methylbenzoate, silver m-methylbenzoate, silver
p-methylbenzoate, silver 2,4-dichlorobenzoate, silver
acetamidobenzoate, silver p-phenylbenzoate, etc., silver gallate,
silver tannate, silver phthalate, silver terephthalate, silver
salicylate, silver phenylacetate, silver pyromellilate, a silver
salt of 3-carboxymethyl-4-methyl-4-thiazoline-2-t- hione or the
like as described in U.S. Pat. No. 3,785,830, and silver salt of an
aliphatic carboxylic acid containing a thioether group as described
in U.S. Pat. No. 3,330,663.
[0138] Furthermore, a silver salt of a compound containing an imino
group can be used. Preferred examples of these compounds include a
silver salt of benzotriazole and a derivative thereof as described
in Japanese patent publications 30270/69 and 18146/70, for example
a silver salt of benzotriazole or methylbenzotriazole, etc., a
silver salt of a halogen substituted benzotriazole, such as a
silver salt of 5-chlorobenzotriazole, etc., a silver salt of
1,2,4-triazole, a silver salt of
3-amino-5-mercaptobenzyl-1,2,4-triazole, of 1H-tetrazole as
described in U.S. Pat. No. 4,220,709, a silver salt of imidazole
and an imidazole derivative, and the like.
[0139] The photosensitive silver halide grains and the organic
silver salt are coated so that they are in catalytic proximity
during development. They can be coated in contiguous layers, but
are preferably mixed prior to coating. Conventional mixing
techniques are illustrated by Research Disclosure, Item 17029,
cited above, as well as U.S. Pat. No. 3,700,458 and published
Japanese patent applications Nos. 32928/75, 13224/74, 17216/75 and
42729/76.
[0140] The photothermographic element can comprise a thermal
solvent. Examples of useful thermal solvents. Examples of thermal
solvents, for example, salicylanilide, phthalimide,
N-hydroxyphthalimide, N-potassium-phthalimide, succinimide,
N-hydroxy-1,8-naphthalimide, phthalazine, 1-(2H)-phthalazinone,
2-acetylphthalazinone, benzanilide, and benzenesulfonamide.
Prior-art thermal solvents are disclosed, for example, in U.S. Pat.
No. 6,013,420 to Windender. Examples of toning agents and toning
agent combinations are described in, for example, Research
Disclosure, June 1978, Item No. 17029 and U.S. Pat. No.
4,123,282.
[0141] Photothermographic elements as described can contain addenda
that are known to aid in formation of a useful image. The
photothermographic element can contain development modifiers that
function as speed increasing compounds, sensitizing dyes,
hardeners, antistatic agents, plasticizers and lubricants, coating
aids, brighteners, absorbing and filter dyes, such as described in
Research Disclosure, December 1978, Item No. 17643 and Research
Disclosure, June 1978, Item No. 17029.
[0142] After imagewise exposure of a photothermographic element,
the resulting latent image can be developed in a variety of ways.
The simplest is by overall heating the element to thermal
processing temperature. This overall heating merely involves
heating the photothermographic element to a temperature within the
range of about 90.degree. C. to about 180.degree. C. until a
developed image is formed, such as within about 0.5 to about 60
seconds. By increasing or decreasing the thermal processing
temperature a shorter or longer time of processing is useful. A
preferred thermal processing temperature is within the range of
about 100.degree. C. to about 160.degree. C. Heating means known in
the photothermographic arts are useful for providing the desired
processing temperature for the exposed photothermographic element.
The heating means is, for example, a simple hot plate, iron,
roller, heated drum, microwave heating means, heated air, vapor or
the like.
[0143] It is contemplated that the design of the processor for the
photothermographic element be linked to the design of the cassette
or cartridge used for storage and use of the element. Further, data
stored on the film or cartridge may be used to modify processing
conditions or scanning of the element. Methods for accomplishing
these steps in the imaging system are disclosed by Stoebe, et al.,
U.S. Pat. No. 6,062,746 and Szajewski, et al., U.S. Pat. No.
6,048,110, commonly assigned, which are incorporated herein by
reference. The use of an apparatus whereby the processor can be
used to write information onto the element, information which can
be used to adjust processing, scanning, and image display is also
envisaged. This system is disclosed in now allowed Stoebe, et al.,
U.S. patent applications Ser. Nos. 09/206,914 filed Dec. 7, 1998
and 09/333,092 filed Jun. 15, 1999, which are incorporated herein
by reference.
[0144] Thermal processing is preferably carried out under ambient
conditions of pressure and humidity. Conditions outside of normal
atmospheric pressure and humidity are useful.
[0145] The components of the photothermographic element can be in
any location in the element that provides the desired image. If
desired, one or more of the components can be in one or more layers
of the element. For example, in some cases, it is desirable to
include certain percentages of the reducing agent, toner,
stabilizer and/or other addenda in the overcoat layer over the
photothermographic image recording layer of the element. This, in
some cases, reduces migration of certain addenda in the layers of
the element.
[0146] In view of advances in the art of scanning technologies, it
has now become natural and practical for photothermographic color
films such as disclosed in EP 0762 201 to be scanned, which can be
accomplished without the necessity of removing the silver or
silver-halide from the negative, although special arrangements for
such scanning can be made to improve its quality. See, for example,
Simmons U.S. Pat. No. 5,391,443.
[0147] Nevertheless, the retained silver halide can scatter light,
decrease sharpness and raise the overall density of the film thus
leading to impaired scanning. Further, retained silver halide can
printout to ambient/viewing/scanning light, render non-imagewise
density, degrade signal-to noise of the original scene, and raise
density even higher. Finally, the retained silver halide and
organic silver salt can remain in reactive association with the
other film chemistry, making the film unsuitable as an archival
media. Removal or stabilization of these silver sources are
necessary to render the PTG film to an archival state.
[0148] Furthermore, the silver coated in the PTG film (silver
halide, silver donor, and metallic silver) is unnecessary to the
dye image produced, and this silver is valuable and the desire is
to recover it is high.
[0149] Thus, it may be desirable to remove, in subsequent
processing steps, one or more of the silver containing components
of the film: the silver halide, one or more silver donors, the
silver-containing thermal fog inhibitor if present, and/or the
silver metal. The three main sources are the developed metallic
silver, the silver halide, and the silver donor. Alternately, it
may be desirable to stabilize the silver halide in the
photothermographic film. Silver can be wholly or partially
stabilized/removed based on the total quantity of silver and/or the
source of silver in the film.
[0150] The removal of the silver halide and silver donor can be
accomplished with a common fixing chemical as known in the
photographic arts. Specific examples of useful chemicals include:
thioethers, thioureas, thiols, thiones, thionamides, amines,
quaternary amine salts, ureas, thiosulfates, thiocyanates,
bisulfites, amine oxides, iminodiethanol-sulfur dioxide addition
complexex, amphoteric amines, bis-sulfonylmethanes, and the
carbocyclic and heterocyclic derivatives of these compounds. These
chemicals have the ability to form a soluble complex with silver
ion and transport the silver out of the film into a receiving
vehicle. The receiving vehicle can be another coated layer
(laminate) or a conventional liquid processing bath.
[0151] The stabilization of the silver halide and silver donor can
also be accomplished with a common stabilization chemical. The
previously mentioned silver salt removal compounds can be employed
in this regard. With stabilization, the silver is not necessarily
removed from the film, although the fixing agent and stabilization
agents could very well be a single chemical. The physical state of
the stabilized silver is no longer in large (>50 nm) particles
as it was for the silver halide and silver donor, so the stabilized
state is also advantaged in that light scatter and overall density
is lower, rendering the image more suitable for scanning.
[0152] The removal of the metallic silver is more difficult than
removal of the silver halide and silver donor. In general, two
reaction steps are involved. The first step is to bleach the
metallic silver to silver ion. The second step may be identical to
the removal/stabilization step(s) described for silver halide and
silver donor above. Metallic silver is a stable state that does not
compromise the archival stability of the PTG film. Therefore, if
stabilization of the PTG film is favored over removal of silver,
the bleach step can be skipped and the metallic silver left in the
film. In cases where the metallic silver is removed, the bleach and
fix steps can be done together (called a blix) or sequentially
(bleach+fix).
[0153] The process could involve one or more of the scenarios or
permutaions of steps. The steps can be done one right after another
or can be delayed with respect to time and location. For instance,
heat development and scanning can be done in a remote kiosk, then
bleaching and fixing accomplished several days later at a retail
photofinishing lab. In one embodiment, multiple scanning of images
is accomplished. For example, an initial scan may be done for soft
display or a lower cost hard display of the image after heat
processing, then a higher quality or a higher cost secondary scan
after stabilization is accomplished for archiving and printing,
optionally based on a selection from the initial display.
[0154] For illustrative purposes, a non-exhaustive list of
photothermographic film processes involving a common dry heat
development step are as follows:
[0155] 1. heat developmentscanstabilize (for example, with a
laminate)scanobtain returnable archival film.
[0156] 2. heat developmentfix bathwater washdryscanobtain
returnable archival film
[0157] 3. heat developmentscanblix bathdryscanrecycle all or part
of the silver in film
[0158] 4. heat developmentbleach laminatefix laminatescan(recycle
all or part of the silver in film)
[0159] 5. heat developmentscanblix bathwashfix bathwashdryobtain
returnable archival film
[0160] 6. heat developmentrelatively rapid, low quality scan
[0161] 7. heat developmentbleachwashfixwashdryrelatively slow, high
quality scan
[0162] Photothermographic or photographic elements of the present
invention can also be subjected to low volume processing
("substantially dry" or "apparently dry") which is defined as
phototographic processing where the volume of applied developer
solution is between about 0.1 to about 10 times, preferably about
0.5 to about 10 times, the volume of solution required to swell the
photographic element. This processing may take place by a
combination of solution application, external layer lamination, and
heating. The low volume processing system may contain any of the
elements described above for photothermographic systems. In
addition, it is specifically contemplated that any components
described in the preceding sections that are not necessary for the
formation or stability of latent image in the origination film
element can be removed from the film element altogether and
contacted at any time after exposure for the purpose of carrying
out photographic processing, using the methods described below.
[0163] An apparently dry photothermographic element or photographic
element may receive some or all of the following three
treatments:
[0164] (I) Application of a solution directly to the film by any
means, including spray, inkjet, coating, gravure process and the
like.
[0165] (II) Soaking of the film in a reservoir containing a
processing solution.
[0166] This process may also take the form of dipping or passing an
element through a small cartridge.
[0167] (III) Lamination of an auxiliary processing element to the
imaging element. The laminate may have the purpose of providing
processing chemistry, removing spent chemistry, or transferring
image information from the latent image recording film element.
[0168] The transferred image may result from a dye, dye precursor,
or silver containing compound being transferred in a image-wise
manner to the auxiliary processing element.
[0169] Heating of a photothermographic element during processing
may be effected by any convenient means, including a simple hot
plate, iron, roller, heated drum, microwave heating means, heated
air, vapor, or the like. Heating may be accomplished before,
during, after, or throughout any of the preceding treatments I-III.
Heating may cause processing temperatures ranging from room
temperature to 100.degree. C. or above.
[0170] Once yellow, magenta, and cyan dye image records (or the
like) have been formed in the processed photographic elements of
the invention, conventional techniques can be employed for
retrieving the image information for each color record and
manipulating the record for subsequent creation of a color balanced
viewable image. For example, it is possible to scan the
photothermographic element successively within the blue, green, and
red regions of the spectrum or to incorporate blue, green, and red
light within a single scanning beam that is divided and passed
through blue, green, and red filters to form separate scanning
beams for each color record. A simple technique is to scan the
photothermographic element point-by-point along a series of
laterally offset parallel scan paths. The intensity of light
passing through the element at a scanning point is noted by a
sensor which converts radiation received into an electrical signal.
Most generally this electronic signal is further manipulated to
form a useful electronic record of the image. For example, the
electrical signal can be passed through an analog-to-digital
converter and sent to a digital computer together with location
information required for pixel (point) location within the image.
In another embodiment, this electronic signal is encoded with
colorimetric or tonal information to form an electronic record that
is suitable to allow reconstruction of the image into viewable
forms such as computer monitor displayed images, television images,
printed images, and so forth.
[0171] It is contemplated that many of imaging elements of this
invention will be scanned prior to the removal of silver halide
from the element. The remaining silver halide yields a turbid
coating, and it is found that improved scanned image quality for
such a system can be obtained by the use of scanners that employ
diffuse illumination optics. Any technique known in the art for
producing diffuse illumination can be used. Preferred systems
include reflective systems, that employ a diffusing cavity whose
interior walls are specifically designed to produce a high degree
of diffuse reflection, and transmissive systems, where diffusion of
a beam of specular light is accomplished by the use of an optical
element placed in the beam that serves to scatter light. Such
elements can be either glass or plastic that either incorporate a
component that produces the desired scattering, or have been given
a surface treatment to promote the desired scattering.
[0172] One of the challenges encountered in producing images from
information extracted by scanning is that the number of pixels of
information available for viewing is only a fraction of that
available from a comparable classical photographic print. It is,
therefore, even more important in scan imaging to maximize the
quality of the image information available. Enhancing image
sharpness and minimizing the impact of aberrant pixel signals
(i.e., noise) are common approaches to enhancing image quality. A
conventional technique for minimizing the impact of aberrant pixel
signals is to adjust each pixel density reading to a weighted
average value by-factoring in readings from adjacent pixels, closer
adjacent pixels being weighted more heavily.
[0173] The elements of the invention can have density calibration
patches derived from one or more patch areas on a portion of
unexposed photographic recording material that was subjected to
reference exposures, as described by Wheeler et al U.S. Pat. No.
5,649,260, Koeng at al U.S. Pat. No. 5,563,717, and by Cosgrove et
al U.S. Pat. No. 5,644,647.
[0174] Illustrative systems of scan signal manipulation, including
techniques for maximizing the quality of image records, are
disclosed by Bayer U.S. Pat. No. 4,553,156; Urabe et al U.S. Pat.
No. 4,591,923; Sasaki et al U.S. Pat. No. 4,631,578; Alkofer U.S.
Pat. No. 4,654,722; Yamada et al U.S. Pat. No. 4,670,793; Klees
U.S. Pat. Nos. 4,694,342 and 4,962,542; Powell U.S. Pat. No.
4,805,031; Mayne et al U.S. Pat. No. 4,829,370; Abdulwahab U.S.
Pat. No. 4,839,721; Matsunawa et al U.S. Pat. Nos. 4,841,361 and
4,937,662; Mizukoshi et al U.S. Pat. No. 4,891,713; Petilli U.S.
Pat. No. 4,912,569; Sullivan et al U.S. Pat. Nos. 4,920,501 and
5,070,413, Kimoto et al U.S. Pat. No. 4,929,979, Hirosawa et al
U.S. Pat. No. 4,972,256; Kaplan U.S. Pat. No. 4,977,521; Sakai U.S.
Pat. No. 4,979,027; Ng U.S. Pat. No. 5,003,494; Katayama et al U.S.
Pat. No. 5,008,950; Kimura et al U.S. Pat. No. 5,065,255; Osamu et
al U.S. Pat. No. 5,051,842; Lee et al U.S. Pat. No. 5,012,333;
Bowers et al U.S. Pat. No. 5,107,346, Telle U.S. Pat. No.
5,105,266; MacDonald et al U.S. Pat. No. 5,105,469, and Kwon et al
U.S. Pat. No. 5,081,692. Techniques for color balance adjustments
during scanning are disclosed by Moore et al U.S. Pat. No.
5,049,984 and Davis U.S. Pat. No. 5,541,645.
[0175] The digital color records once acquired are in most
instances adjusted to produce a pleasingly color balanced image for
viewing and to preserve the color fidelity of the image bearing
signals through various transformations or renderings for
outputting, either on a video monitor or when printed as a
conventional color print. Preferred techniques for transforming
image bearing signals after scanning are disclosed by Giorgianni et
al U.S. Pat. No. 5,267,030, the disclosures of which are herein
incorporated by reference. Further illustrations of the capability
of those skilled in the art to manage color digital image
information are provided by Giorgianni and Madden Digital Color
Management, Addison-Wesley, 1998.
EXAMPLE 1
[0176] The following examples illustrate the synthesis of some
blocked developers that are useful in the invention.
[0177] Preparation of D-2: 21
[0178] Preparation of2:
[0179] Water (450 mL) was slowly added at 0.degree. C. to a mixture
of 2,6-dimethyl-4-(N,N-diethyl)aniline ditosylate (1) (268.4 g,
0.50 mol), potassium bicarbonate (500.6 g, 5.00 mol) and
dichloromethane (900 mL), followed by a 1.9M toluene solution of
phosgene (550 mL, 1.00 mol) at 4-7.degree. C. over a period of 30
min. Following the addition, the mixture was stirred cold for 30
min and diluted with dichloromethane (750 mL) and water (1000 mL).
The layers were separated and the aqueous one extracted with
dichloromethane (350 mL). Combined organic solutions were dried
over sodium sulfate and the solvents were distilled off in vacuo at
45.degree. C. The crude product was dissolved in ligroin (700 mL),
the solution treated with charcoal, filtered through SuperCel and
concentrated in vacuo at 50.degree. C., giving 111.0 g (0.50 mol,
100%) of isocyanate 2 as a yellow oil. .sup.1H NMR (CDCl.sub.3):
.delta.6.35 (s, 2H), 3.30 (q, 4H), 2.25 (s, 6H), 1.15 (t, 6H).;
[0180] Preparation of D-2:
[0181] A solution of isocyanate 2 (177.6 g, 0.81 mol), diol 3 (87.1
g, 0.375 mol) and dibutyltin diacetate (1 mL) in 900 mL of
acetonitrile was stirred at 50.degree. C. under nitrogen for 3 days
The mixture was cooled to room temperature, filtered and the
filtrate taken to dryness. The crystalline residue was stirred with
isopropyl ether (500 mL), the product collected by filtration,
washed with isopropyl ether (2.times.250 mL) and then ethanol
(2.times.250 mL). Yield 220.9 g (0.33 mol, 88%),
m.p.173-175.degree. C.
[0182] Preparation of D-3, D-4 and D-9:
[0183] Blocked developers D-3, D-4 and D-9 were prepared as
described above for D-2 from isocyanate 2 and appropriate alcohols
in the presence of catalytic amounts of dibutyltin diacetate. The
yields and melting points are listed below in Table 1 below.
2TABLE 1 Developer Yield (%) m.p.(.degree. C.) D-3 161-163 D-4 84
91-93 D-9 79 110-114
EXAMPLE 2
[0184] A hardened silver halide color photothermographic element is
prepared having:
[0185] (A) a red-light-sensitive silver halide layer unit with 2.37
g/m.sup.2 of silver behenate, 0.43 g/m.sup.2 of coupler A-1, and a
blocked developer which liberates 0.2 g of
4-N,N-diethyl-2,6-dimethylphen- lyenediamine on heating, all in
4.74 g/m.sup.2 of gelatin;
[0186] (B) a green-light-sensitive layer unit with 2.37 g/m.sup.2
of silver behenate, 0.43 g/m.sup.2 of coupler A-1, and a blocked
developer which liberates 0.2 g of
4-(N-ethyl-N-2-hydroxyethyl)-2-methylphenylenedi- amine on heating,
all in 4.74 g/m.sup.2 of gelatin; and
[0187] (C) a blue-light-sensitive layer unit with 2.37 g/m.sup.2 of
silver behenate, 0.43 g/m.sup.2 of coupler A-1, and a blocked
developer which liberates 0.2 g of 2-hyrazinobenzothiazole on
heating, all in 4.74 g/m.sup.2 of gelatin.
[0188] The element further consists of a protective overcoat and
conventional components as known in the art. The photographic
element is imagewise exposed to white light and thermally
developed. A red density of 1.46, a green density of 1.92 and a
blue density of 1.85 is formed. The formed deposits have excellent
stability and fastness.
[0189] The invention has been described in detail with particular
reference to certain preferred embodiments thereof, but it will be
understood that variations and modifications can be effected within
the spirit and scope of the invention.
* * * * *