US3887372A — Photographic elements and processes for producing…

Claim 1

Independent Claim 135 words

In a photographic element having a support and at least one radiation-sensitive image recording layer thereon comprised of a source of labile hydrogen atoms, a tetrazolium salt capable of reduction to a formazan dye and a photoreductant capable of forming a base activatible reducing agent precursor on exposure to actinic radiation in the presence of said labile hydrogen atoms, the improvement in which said tetrazolium salt includes dye stabilizing tetrazole nucleus substituents which are, collectively, predominantly electronegative so that the algebraic sum of the Hammett sigma values of the tetrazole nucleus substituents are a. in excess of 0.78 or b. in excess of 0.40 when said tetrazole nucleus is provided with a ring substituent bonded to said teTrazole nucleus at a first ring position and including a single substituent ortho to said first ring position.

Claim 2

Dependent Claim 135 words

In a photographic element having a support and at least one radiation-sensitive image recording layer thereon comprised of a source of labile hydrogen atoms, a tetrazolium salt capable of reduction to a formazan dye and a photoreductant capable of forming a base activatible reducing agent precursor on exposure to actinic radiation in the presence of said labile hydrogen atoms, the improvement in which said tetrazolium salt includes dye stabilizing tetrazole nucleus substituents which are, collectively, predominantly electronegative so that the algebraic sum of the Hammett sigma values of the tetrazole nucleus substituents are a. in excess of 0.78 or b. in excess of 0.40 when said tetrazole nucleus is provided with a ring substituent bonded to said teTrazole nucleus at a first ring position and including a single substituent ortho to said first ring position.

Claim 3

Dependent Claim 135 words

IN A PHOTOGRAPHIC ELEMENT HAVING A SUPPORT AND AT LEAST ONE RADIATION-SENSITIVE IMAGE RECORDING LAYER THEREON COMPRISED OF A SOURCE OF LABILE HYDROGEN ATOMS, A TETRAZOLIUM SALT CAPABLE OF REDUCITION TO A FORMAZAN DYE AND A PHOTOREDUCTANT CAPABLE OF FORMING A BASE ACTIVATIBLE REDUCING AGENT PRECURSOR ON EXPOSURE TO ACTINIC RADIATION IN THE PRESENCE OF SAID LABILE HYDROGEN ATOMS, THE IMPROVEMENT IN WHICH SAID TETRAZOLIUM SALT INCLUDES DYE STABILIZING TETRAZOLE NUCLEUS SUBSTITUENTS WHICH ARE, COLLECTIVELY PREDOMINANTLY ELECTRONEGATIVE SO THAT THE ALGEBRAIC SUM OF THE HAMMETT SIGMA VALUES OF THE TETRAZOLE NUCLEUS SUBSTITUENTS ARE A. IN EXCESS OF 0.78 OR B. IN EXCESS OF 0.40 WHEN SAID TETRAZOLE NUCLEUS IS PROVIDED WITH A RING SUBSTITUENT BONDED TO SAID TETRAZOLE NUCLEUS AT A FIRST RING POSITION AND INCLUDING A SINGLE SUBSTITUENT ORTHO TO SAID FIRST RING POSITION.

Claim 4

Dependent Claim 135 words

IN A PHOTOGRAPHIC ELEMENT HAVING A SUPPORT AND AT LEAST ONE RADIATION-SENSITIVE IMAGE RECORDING LAYER THEREON COMPRISED OF A SOURCE OF LABILE HYDROGEN ATOMS, A TETRAZOLIUM SALT CAPABLE OF REDUCITION TO A FORMAZAN DYE AND A PHOTOREDUCTANT CAPABLE OF FORMING A BASE ACTIVATIBLE REDUCING AGENT PRECURSOR ON EXPOSURE TO ACTINIC RADIATION IN THE PRESENCE OF SAID LABILE HYDROGEN ATOMS, THE IMPROVEMENT IN WHICH SAID TETRAZOLIUM SALT INCLUDES DYE STABILIZING TETRAZOLE NUCLEUS SUBSTITUENTS WHICH ARE, COLLECTIVELY PREDOMINANTLY ELECTRONEGATIVE SO THAT THE ALGEBRAIC SUM OF THE HAMMETT SIGMA VALUES OF THE TETRAZOLE NUCLEUS SUBSTITUENTS ARE A. IN EXCESS OF 0.78 OR B. IN EXCESS OF 0.40 WHEN SAID TETRAZOLE NUCLEUS IS PROVIDED WITH A RING SUBSTITUENT BONDED TO SAID TETRAZOLE NUCLEUS AT A FIRST RING POSITION AND INCLUDING A SINGLE SUBSTITUENT ORTHO TO SAID FIRST RING POSITION.

Claim 5

Dependent Claim 24 words

In a photographic element according to claim 1 the further improvement in which said source of labile hydrogen atoms in external of said photoreductant.

Claim 6

Dependent Claim 47 words

In a photographic element according to claim 2 the further improvement in which said external hydrogen source incorporates a labile hydrogen atom attached to a carbon atom which is also bonded to the oxygen atom of an oxy substituent or the nitrogen atom of an amine substituent.

Claim 7

Dependent Claim 31 words

In a photographic element according to claim 2 the further improvement in which said external hydrogen source is a polymer and also serves as a binder for said image recording layer.

Claim 8

Dependent Claim 20 words

In a photographic element according to claim 4 the further improvement in which siad polymer binder is a cellulosic compound.

Claim 9

Dependent Claim 20 words

In a photographic element according to claim 5 the further improvement in which said polymer binder is cellulose acetate butyrate.

Claim 10

Dependent Claim 20 words

In a photographic element according to claim 4 the further improvement in which said polymer binder is a poly(vinyl acetal).

Claim 11

Dependent Claim 19 words

In a photographic element according to claim 7 the further improvement in which said polymer binder is poly(vinyl butyral).

Claim 12

Dependent Claim 19 words

In a photographic element according to claim 2 the further improvement in which said external hydrogen source is nitrilotriacetonitrile.

Claim 13

Dependent Claim 19 words

In a photographic element according to claim 2 the further improvement in which said external hydrogen source is phenyl-1,2-ethanediol.

Claim 14

Dependent Claim 21 words

In a photographic element according to claim 2 the further improvement in which said external hydrogen source is a poly(alkylene glycol).

Claim 15

Dependent Claim 20 words

In a photographic element according to claim 11 the further improvement in which said external hydrogen source is poly(ethylene glycol).

Claim 16

Dependent Claim 18 words

In a photographic element according to claim 1 the further improvement in which said photoreductant is a nitroarene.

Claim 17

Dependent Claim 18 words

In a photographic element according to claim 13 the further improvement in which said photoreductant is a halonitroarene.

Claim 18

Dependent Claim 18 words

In a photographic element according to claim 14 the further improvement in which said photoreductant is a halonitrobenzene.

Claim 19

Dependent Claim 18 words

In a photographic element according to claim 15 the further improvement in which said photoreductant is a 4-halonitrobenzene.

Claim 20

Dependent Claim 17 words

In a photographic element according to claim 16 the further improvement in which said photoreductant is 4-bromonitrobenzene.

Claim 21

Dependent Claim 19 words

In a photographic element according to claim 1 the further improvement in which said photoreductant is a phenazinium salt.

Claim 22

Dependent Claim 19 words

In a photographic element according to claim 18 the further improvement in which said phenazinium salt is phenazinium 4-toluenesulfonate.

Claim 23

Dependent Claim 18 words

In a photographic element according to claim 1 the further improvement in which said photoreductant is a disulfide.

Claim 24

Dependent Claim 34 words

In a photographic element according to claim 20 the further improvement in which said photoreductant is an aryl disulfide capable of being cleaved at the S-S bond by actinic radiation to form a mercaptan.

Claim 25

Dependent Claim 18 words

In a photographic element according to claim 21 the further improvement in which said photoreductant is 1-naphthyl-1''-phenethyl disulfide.

Claim 26

Dependent Claim 18 words

In a photographic element according to claim 1 the further improvement in which said photoreductant is a diazoanthrone.

Claim 27

Dependent Claim 18 words

In a photographic element according to claim 23 the further improvement in which said diazoanthrone is a 10-diazoanthrone.

Claim 28

Dependent Claim 18 words

In a photographic element according to claim 1 the further improvement in which said photoreductant is a beta-ketosulfide.

Claim 29

Dependent Claim 18 words

In a photographic element according to claim 25 the further improvement in which said photoreductant is a thiochromanone.

Claim 30

Dependent Claim 17 words

In a photographic element according to claim 26 the further improvement in which said photoreductant is 2-(4-tolyl)thiochromanone.

Claim 31

Dependent Claim 38 words

In a photographic element according to claim 1 the further improVement in which said photoreductant is a quinone, a disulfide, a phenazinium salt, a beta-ketosulfide, a nitroarene, a diazoanthrone, or a mixture of two or more of these.

Claim 32

Dependent Claim 36 words

In a photographic element according to claim 1 the further improvement in which said tetrazolium salt contains 2 and 3 position tetrazole ring substituents chosen from the class consisting of pyridyl, quinolinyl, azolyl and aryl substituents.

Claim 33

Dependent Claim 21 words

In a photographic element according to claim 29 the further improvement in which said tetrazolium salt is a 2,3-diaryl tetrazolium salt.

Claim 34

Dependent Claim 20 words

In a photographic element according to claim 30 the further improvement in which said tetrazolium salt is a 2,3,5-triaryltetrazolium salt.

Claim 35

Dependent Claim 20 words

In a photographic element according to claim 31 the further improvement in which said tetrazolium salt is a 2,3,5-triphenyltetrazolium salt.

Claim 36

Dependent Claim 21 words

In a photographic element according to claim 32 the further improvement in which said phenyl substituents are halogen or nitro substituted.

Claim 37

Dependent Claim 32 words

In a photographic element according to claim 33 the further improvement in which at least one of said phenyl substituents contains a single ortho substituent, which is a halogen or nitro substituent.

Claim 38

Dependent Claim 34 words

In a photographic element according to claim 34 the further improvement in which said tetrazolium salt is chosen from the class consisting of 2-(2-bromophenyl)-3-(2-nitrophenyl)-5-phenyl-2H-tetrazolium salt; 2,3-di(2-chlorophenyl)-5-phenyl-2H-tetrazolium salt; 2-(2nitrophenyl)-3,5-diphenyl-2H-tetrazolium tetrafluoroborate; 2-(2-chlorophenyl)-3-phenyl-5-(3-nitrophenyl)-2H-tetrazolium salt; and 2-(2,4-dinitrophenyl)-3,5-diphenyl-2H-tetrazolium salt.

Claim 39

Dependent Claim 20 words

In a photographic element according to claim 33 the further improvement in which said tetrazolium salt is a 2,3-di(4-nitrophenyl)-5-phenyl-2H-tetrazolium chloride.

Claim 40

Dependent Claim 24 words

In a photographic element according to claim 33 the further improvement in which said tetrazolium salt is a 2-(4-nitrophenyl)-3,5-diphenyl-2H-tetrazolium salt or a 2,3-di(4-nitrophenyl)-5-(4-alkoxyphenyl)-2H-tetrazolium salt.

Claim 41

Dependent Claim 25 words

In a photographic element according to claim 29 the further improvement in which said tetrazolium salt contains halogen or nitro substituents to said ring substituents.

Claim 42

Dependent Claim 20 words

In a photographic element according to claim 38 the further improvement in which said tetrazolium salt contains a 2-(2-pyridyl)-3-(4-halophenyl)-5-phenyl-2H-tetrazolium salt.

Claim 43

Dependent Claim 38 words

In a photographic element according to claim 29 the further improvement in which said tetrazolium salt contains at least one 2-pyridyl or 2-azolyl tetrazole nucleus substituent in the 2 or 3 position capable of forming a tridentate chelate.

Claim 44

Dependent Claim 31 words

In a photographic element according to claim 1 the further improvement additionally including means incorporated within said image recording layer capable of interacting with a formazan dye to form a chelate.

Claim 45

Dependent Claim 31 words

In a photographic element according to claim 41 the further improvement in which said chelating means is chosen from the class consisting of copper, zinc, mercury, cadmium, cobalt and nickel salts.

Claim 46

Dependent Claim 20 words

In a photographic element according to claim 41 the further improvement in which said chelating means is a metal carboxylate.

Claim 47

Dependent Claim 22 words

In a photographic element according to claim 1 the further improvement in which said tetrazolium salt is a tetrafluoroborate or a hexafluorophosphate.

Claim 48

Dependent Claim 27 words

In a photographic element according to claim 1 the further improvement in which from 0.1 to 10 moles of tetrazolium salt are present per mole of photoreductant.

Claim 49

Dependent Claim 33 words

In a photographic element according to claim 2 the further improvement in which said external hydrogen source means is present in a conceNtration of at least 0.5 moles per mole of said photoreductant.

Claim 50

Dependent Claim 34 words

In a photographic element according to claim 1 the further improvement in which said photographic element incorporates a binder in said image recording layer in a concentration of up to 99 percent by weight.

Claim 51

Dependent Claim 35 words

In a photographic element according to claim 47 the further improvement in which said photographic element incorporates a binder in said image recording layer in a concentration of from 50 to 90 percent by weight.

Claim 52

Dependent Claim 26 words

In a photographic element according to claim 45 the further improvement in which said photoreductant and said tetrazolium salt are present in substantially equal molar proportions.

Claim 53

Dependent Claim 140 words

In a photographic element having a support and at least one radiation-sensitive image recording layer thereon comprised of a source of labile hydrogen atoms, a tetrazolium salt capable of reduction to a formazan dye, a quinone photoreductant capable of forming a base activatible reducing agent precursor on exposure to actinic radiation in the presence of said labile hydrogen atoms, the improvement in which said tetrazolium salt includes dye stabilizing tetrazole nucleus substituents which are, collectively, predominantly electronegative so that the algebraic sum of the Hammett sigma values of the tetrazole nucleus substituents are a. in excess of 0.78 or b. in excess of 0.40 when said tetrazole nucleus is provided with a ring substituent bonded to said tetrazole nucleus at a first ring position and including a single substituent alpha to said first ring position, said alpha substituent being electronegative.

Claim 54

Dependent Claim 140 words

In a photographic element having a support and at least one radiation-sensitive image recording layer thereon comprised of a source of labile hydrogen atoms, a tetrazolium salt capable of reduction to a formazan dye, a quinone photoreductant capable of forming a base activatible reducing agent precursor on exposure to actinic radiation in the presence of said labile hydrogen atoms, the improvement in which said tetrazolium salt includes dye stabilizing tetrazole nucleus substituents which are, collectively, predominantly electronegative so that the algebraic sum of the Hammett sigma values of the tetrazole nucleus substituents are a. in excess of 0.78 or b. in excess of 0.40 when said tetrazole nucleus is provided with a ring substituent bonded to said tetrazole nucleus at a first ring position and including a single substituent alpha to said first ring position, said alpha substituent being electronegative.

Claim 55

Dependent Claim 40 words

In a photographic element according to claim 50 the further improvement in which said quinone incorporates at least one alkyl, alkenyl, alkynyl, aryl, alkoxy, aryloxy, alkaryloxy, hydroxyalkyl, alkylcarbonyl, carboxyl, amino, aminoalkyl, amidoalkyl, anilino, piperidino, pyrrolidino, morpholino, nitro or halide substituent.

Claim 56

Dependent Claim 23 words

In a photographic element according to claim 51 the further improvement in which said quinone incorporates at least one phenyl or phenoxy substituent.

Claim 57

Dependent Claim 38 words

In a photographic element according to claim 52 the further improvement in which each of said alkyl, alkenyl and alkynyl substituents, whether present as separate substituents or in combination with other substituents, incorporate twenty or fewer carbon atoms.

Claim 58

Dependent Claim 38 words

In a photographic element according to claim 53 the further improvement in which each of said alkyl, alkenyl and alkynyl substituents, whether present as separate substituents or in combination with other substituents, incorporate six or fewer carbon atoms.

Claim 59

Dependent Claim 18 words

In a photographic element according to claim 50 the further improvement in which said quinone is a benzoquinone.

Claim 60

Dependent Claim 18 words

In a photographic element according to claim 55 the further improvement in which said benzoquinone is a 1,4-benzoquinone.

Claim 61

Dependent Claim 23 words

In a photographic element according to claim 56 the further improvement in which said 1,4-benzoquinone is 2,5-dimethyl-1,4-benzoquinone; duroquinone; 2,5-di-t-butyl-1,4-benzoquinone; 2,3, 5-trimethyl-6-bromo-1,4-benzoquinone; or 2-phenyl-1,4-benzoquinone.

Claim 62

Dependent Claim 18 words

In a photographic element according to claim 50 the further improvement in which said quinone is a naphthoquinone.

Claim 63

Dependent Claim 18 words

In a photographic element according to claim 58 the further improvement in which said naphthoquinone is a 1,4-naphthoquinone.

Claim 64

Dependent Claim 24 words

In a photographic element according to claim 59 the further improvement in which said 1,4-naphthoquinone is 2-methyl-1,4-naphthoquinone; 2,3-dimethyl-1,4-naphthoquinone; 2,3-dichloro-1, 4-naphthoquinone; 2-thiomethyl-1,4-naphthoquinone; 2-acetylthiomethyl-3-methyl-1,4-naphthoquinone; or 1,4-naphthoquinone.

Claim 65

Dependent Claim 18 words

In a photographic element according to claim 50 the further improvement in which said quinone is an anthroquinone.

Claim 66

Dependent Claim 17 words

In a photographic element according to claim 61 the further improvement in which said anthroquinone is 2-t-butylanthraquinone.

Claim 67

Dependent Claim 113 words

In a photographic element having a support and at least one radiation-sensitive image recording layer thereon comprised of a source of labile hydrogen atoms, a tetrazolium salt capable of reduction to a formazan dye and a quinone photoreductant capable of forming a base activatible reducing agent precursor on exposure to actinic radiation in the presence of said labile hydrogen atoms, the improvement in which said tetrazolium salt includes dye stabilizing 2 and 3 position tetrazole nucleus substituents chosen from the class consisting of pyridyl, azolyl, quinolinyl and aryl substituents which are, collectively, predominantly electronegative, with the algebraic sum of the Hammett sigma values of all tetrazole nucleus substituents being in excess of 1.00.

Claim 68

Dependent Claim 113 words

In a photographic element having a support and at least one radiation-sensitive image recording layer thereon comprised of a source of labile hydrogen atoms, a tetrazolium salt capable of reduction to a formazan dye and a quinone photoreductant capable of forming a base activatible reducing agent precursor on exposure to actinic radiation in the presence of said labile hydrogen atoms, the improvement in which said tetrazolium salt includes dye stabilizing 2 and 3 position tetrazole nucleus substituents chosen from the class consisting of pyridyl, azolyl, quinolinyl and aryl substituents which are, collectively, predominantly electronegative, with the algebraic sum of the Hammett sigma values of all tetrazole nucleus substituents being in excess of 1.00.

Claim 69

Dependent Claim 118 words

In a photographic element having a support and at least one radiation-sensitive image recording layer thereon comprised of a source of labile hydrogen atoms, a tetrazolium salt capable of reduction to a formazan dye and a quinone photoreductant capable of forming a base activatible reducing agent precurson on exposure to actinic radiation in the presence of said labile hydrogen atoms, the improvement in which said tetrazolium salt includes dye stabilizing 2 and 3 position tetrazole nucleus phenyl substituents which are, collectively, predominantly electronegative, with the algebraic sum of the Hammett sigma values of all tetrazole nucleus substituents being in excess of 0.50 when at least one of said 2 and 3 position phenyl substituents are singly ortho substituted.

Claim 70

Dependent Claim 118 words

In a photographic element having a support and at least one radiation-sensitive image recording layer thereon comprised of a source of labile hydrogen atoms, a tetrazolium salt capable of reduction to a formazan dye and a quinone photoreductant capable of forming a base activatible reducing agent precurson on exposure to actinic radiation in the presence of said labile hydrogen atoms, the improvement in which said tetrazolium salt includes dye stabilizing 2 and 3 position tetrazole nucleus phenyl substituents which are, collectively, predominantly electronegative, with the algebraic sum of the Hammett sigma values of all tetrazole nucleus substituents being in excess of 0.50 when at least one of said 2 and 3 position phenyl substituents are singly ortho substituted.

Claim 71

Dependent Claim 149 words

An image recording process comprising converting a photoreductant capable of forming a base activatible reducing agent precursor on exposure to actinic radiation, within a selected areal portion of a radiation-sensitive layer of a photographic element, to a reducing agent precursor by imagewise exposing the photoreductant to actinic radiation while in reactive contact with labile hydrogen atoms, activating the precursor with a base to form a reducing agent; and reducing to produce a formazan dye of enhanced stability a tetrazolium salt including dye stabilizing tetrazole nucleus substituents which are, collectively, predominantly electronegative so that the algebraic sum of the Hammett sigma values of the tetrazole nucleus substituents are a. in excess of 0.78 or b. in excess of 0.40 when the tetrazole nucleus is provided with a ring substituent bonded to the tetrazole nucleus at a first ring position and including a single substituent ortho to the first ring position.

Claim 72

Dependent Claim 149 words

An image recording process comprising converting a photoreductant capable of forming a base activatible reducing agent precursor on exposure to actinic radiation, within a selected areal portion of a radiation-sensitive layer of a photographic element, to a reducing agent precursor by imagewise exposing the photoreductant to actinic radiation while in reactive contact with labile hydrogen atoms, activating the precursor with a base to form a reducing agent; and reducing to produce a formazan dye of enhanced stability a tetrazolium salt including dye stabilizing tetrazole nucleus substituents which are, collectively, predominantly electronegative so that the algebraic sum of the Hammett sigma values of the tetrazole nucleus substituents are a. in excess of 0.78 or b. in excess of 0.40 when the tetrazole nucleus is provided with a ring substituent bonded to the tetrazole nucleus at a first ring position and including a single substituent ortho to the first ring position.

Claim 73

Dependent Claim 149 words

AN IMAGE RECORDING PROCESS COMPRISING CONVERTING A PHOTOREDUCTANT CAPABLE OF FORMING A BASE ACRIVATIBLE REDUCING AGENT PRECURSOR ON EXPOSURE TO ACTINIC RADIATION, WITHIN A SELECTED AREAL PORTION OF A RADIATION-SENSITIVE LAYER OF A PHOTOGRAPHIC ELEMENT, TO A REDUCING AGENT PRECURSOR BY IMAGEWISE EXPOSING THE PHOTOREDUCTANT TO ACTINIC RADIATION WHILE IN REACTIVE CONTACT WITH LABILE HYDROGEN ATOMS, ACTIVATING THE PRECURSOR WITH A BASE TO FORM A REDUCING AGENT; AND REDUCING TO PRODUCE A FORMAZAN DYE OF ENHANCED STABILITY A TETRAZOLIUM SALT INCLUDING DYE STABILIZING TETRAZLE NUCLEUS SUBSTITUENTS WHICH ARE, COLLECTIVELY, PREDOMINANTLY ELECTRONEGATIVE SO THAT THE ALGEBRAIC SUM OF THE HAMMETT SIGMA VALUES OF THE TETRAZOLE NUCLEUS SUBSTITUENTS ARE A. IN EXCESS OF 0.78 OR B. IN EXCESS OF 0.40 WHEN THE TETRAZOLE NUCLEUS IS PROVIDED WITH A RING SUBSTITUENT BONDED TO THE TETRAZOLE NUCLEUS AT A FIRST RING POSITION AND INCLUDING A SINGLE SUBSTITUENT ORTHO TO THE FIRST RING POSITION.

Claim 74

Dependent Claim 149 words

AN IMAGE RECORDING PROCESS COMPRISING CONVERTING A PHOTOREDUCTANT CAPABLE OF FORMING A BASE ACRIVATIBLE REDUCING AGENT PRECURSOR ON EXPOSURE TO ACTINIC RADIATION, WITHIN A SELECTED AREAL PORTION OF A RADIATION-SENSITIVE LAYER OF A PHOTOGRAPHIC ELEMENT, TO A REDUCING AGENT PRECURSOR BY IMAGEWISE EXPOSING THE PHOTOREDUCTANT TO ACTINIC RADIATION WHILE IN REACTIVE CONTACT WITH LABILE HYDROGEN ATOMS, ACTIVATING THE PRECURSOR WITH A BASE TO FORM A REDUCING AGENT; AND REDUCING TO PRODUCE A FORMAZAN DYE OF ENHANCED STABILITY A TETRAZOLIUM SALT INCLUDING DYE STABILIZING TETRAZLE NUCLEUS SUBSTITUENTS WHICH ARE, COLLECTIVELY, PREDOMINANTLY ELECTRONEGATIVE SO THAT THE ALGEBRAIC SUM OF THE HAMMETT SIGMA VALUES OF THE TETRAZOLE NUCLEUS SUBSTITUENTS ARE A. IN EXCESS OF 0.78 OR B. IN EXCESS OF 0.40 WHEN THE TETRAZOLE NUCLEUS IS PROVIDED WITH A RING SUBSTITUENT BONDED TO THE TETRAZOLE NUCLEUS AT A FIRST RING POSITION AND INCLUDING A SINGLE SUBSTITUENT ORTHO TO THE FIRST RING POSITION.

Claim 75

Dependent Claim 16 words

An image recording process according to claim 65 comprising utilizing the base in the gaseous phase.

Claim 76

Dependent Claim 16 words

An image recording process according to claim 65 in which the precursor is activated by ammonia.

Claim 77

Dependent Claim 13 words

An image recording process according to claim 65 comprising chelating the formazan dye.

Claim 78

Dependent Claim 22 words

An image recording process according to claim 65 in which the radiation-sensitive layer of the photographic element is exposed to visible light.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1978-06-02	1978-12-02	1979-06-03	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1982-06-02	1982-12-02	1983-06-03	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1986-06-02	1986-12-02	1987-06-03	$7700.00	Window Closed / Lapsed

Photographic elements and processes for producing formazan dye images of enhanced stability

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag