CA2016495A1 - Speed and contrast promoted silver halide doped emulsions - Google Patents
Speed and contrast promoted silver halide doped emulsionsInfo
- Publication number
- CA2016495A1 CA2016495A1 CA 2016495 CA2016495A CA2016495A1 CA 2016495 A1 CA2016495 A1 CA 2016495A1 CA 2016495 CA2016495 CA 2016495 CA 2016495 A CA2016495 A CA 2016495A CA 2016495 A1 CA2016495 A1 CA 2016495A1
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- CA
- Canada
- Prior art keywords
- emulsion
- silver halide
- contrast
- speed
- moieties
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
- G03C1/00—Photosensitive materials
- G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
- G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
- G03C1/08—Sensitivity-increasing substances
- G03C1/10—Organic substances
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
- G03C1/00—Photosensitive materials
- G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
- G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
- G03C1/067—Additives for high contrast images, other than hydrazine compounds
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
- G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
- G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
- G03C5/29—Development processes or agents therefor
- G03C5/305—Additives other than developers
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- Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- General Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
ABSTRACT
SPEED AND CONTRAST PROMOTED SILVER HALIDE DOPED EMULSIONS
Negative-acting silver halide photographic materials comprising Group VIII metal doped silver halide emulsions free from contrast-promoting amounts of hydrazine derivatives containing as speed and contrast promoting agents one or more compounds of the general formula:
(i) (ii)
SPEED AND CONTRAST PROMOTED SILVER HALIDE DOPED EMULSIONS
Negative-acting silver halide photographic materials comprising Group VIII metal doped silver halide emulsions free from contrast-promoting amounts of hydrazine derivatives containing as speed and contrast promoting agents one or more compounds of the general formula:
(i) (ii)
Description
SPEED AND CONTRAST PROMOTED SILVER H~LIDE DOPED EMULSIONS
This invention relates to negative~acting silver halide photographic materials and in particular to photographic elements comprising Group VIII metal doped silver halide emulsions associated with a speed and contrast promoting agent which are suitable for use in the photolithographic printing industry and for the development of daylight handleable contact film.
Photosensitive silver halide materials are commonly used in the photolithographic industry to obtain half tone, dot or line, high contrast images.
To increase the contrast of lithographic films it is common practice to dope the silver halide emulsions with contrast promoting agents, among which are the water soluble Group VIII metal salts, such as the trivalent salts of rhodium, ruthenium and iridium. It is known that good results as regards high covering power (which is the ratio between the maximum density obtained after development and the silver halide coverage) and rapid developability (for productivity increase) can be obtained by using fine grained (less than 0.15 ~m) and high chloride content silver halide emulsions. It is known that such emulsions which contain a Group VIII
metal as a contrast promoting agent may still not have - 25 the required contrast, and as the dopant desensitises the emulsion, it may not have the required speed.
One approach to the development of a daylight handleable contact film has been to modify existing -daylight duplicating film. Contact films are negative acting materials which are exposed in contact with an original to record a negative image of the original.
Duplicating films are positive acting materials which are exposed in contact with an original to produce an identical copy. To produce a duplicating film, the emulsion is chemically fogged, a metal dopant such as rhodium being required for the reversal process as well as for desensitising purposes. For a contact film, the unfogged duplicating emulsion is far too slow for practical use, primarily due to the level of dopant. As stated previously it is advantageous to have the dopant present for contrast enhancement purposes but to increase the speed and also contrast to usable levels a sensitisation step must be introduced. Conventional gold and sulphur sensitisation does confer some extra speed and contrast but European Patent Applications Nos. 267598 and 138200 and British Patent Applications Nos. 2202341 and 2206700 disclose negative-acting rhodium doped emulsions in which the contrast is enhanced by addition of a hydrazine derivative. Such materials are generally too sensitive to be daylight-handleable, and if this property is required, a desensitiser must be added.
Various examples of the latter are disclosed, including 2-mercaptobenzimidazole derivatives.
British Patent No. 741228 discloses the use of 4-substituted 3-amino-5-mercapto-4,1,2-triazoles of general formula (I) (I) ~- ~ -H ~ IN 2 in which:
R represents other than H, in photographic constructions. The compounds of formula (I) are said to restrain the formation of chemical fog without seriously affecting the speed, contrast or other properties of the emulsion.
British Patent No. 2573027 discloses the use of compounds of general formulae (II) and (III) ( Cl ) ~(, C~ N
, 35 ~ l NH
S H y ~ ~ / S
, b;9 a~ ~ ~
in whicb:
X represents 0 or S, Y represents 0, S or NH, and, D represents substituted or unsubstituted carbon atoms to complete a 6 membered ring, in a photographic construction as anti-bronzing agents.
However, within the patent there is no mention of doping of the emulsions.
U.S. Patent No. 1,725,934 discloses the use of thiazole derivatives in silver halide constructions, but as an anti-fogging agent.
The combination of a triazole (IVa) and tetrazaindene (IVb) is known in the photographic art to act as a stabiliser.
(nUb) (l~
H~ ~ ~ ~ N c ~ \
C ---SC 1~3 ¦ I~ H
H0~2C~
0ll 5C~3 It has now been found that certain groups of compounds, some of which have previously been used as desensitisers, antifoggants, anti-bronzing agents or stabilisers, have a particular utility as speed and contrast promoting agents in Group VIII metal doped, negative-acting silver halide emulsions, the emulsions being chemically-sensitised or otherwise, and being free from contrast-promoting amounts of hydrazine derivatives.
According to one aspect of the present invention there is provided a photographic element comprising a Group VIII metal doped negative-acting silver halide emulsion characterised in that the emulsion is associated with one or more speed and contrast promoting agents comprising a compound having a nucleus of one of the following general formulae (i) to (iv) :
t ~, ! ~ . ,:;, ` ~ ~ '~' '` ' 4 ~ 'J iL ~
(i3 ~ ) N~X
C/ ~C~SI ~ N/ --S/
, (;" ) R4 (1~) R ~ ~1 R~C~C:~C/3 3 ~C// ~N.llcl -~4~ ~C~ C~ 2~ . 5 in which:
Each Rl independently represents a hydrogen atom or an alkyl group of 1 to 5 carbon atoms, op~ionally having one or more substituents selected Erom hydroxyl moieties, carboxyl moieties, alkoxy carbonyl yroups of 1 to 5 carbon atoms,.cyano moieties, halogen atoms, nitro moieties, amino moieties and aryl CJrOUpS O~ Up to 10 carbon atoms, wherein the aryl yroup may be optionally substituted with one or more substituents selected from alkyl groups of 1 to 5 carbon atoms, hydroxyl moieties, carboxyl moieties, alkoxy carbonyl yroups oE 1 to 5 carbon atoms, cyano moieties, llaloyen atoms, nitro moieties and amino moieties, Xl represents N or CR5, where R5 represents Rl (as defined above) or N02, R2 represents a hydroyen atom or SR1 (Rl is as '35 defined,,above) but if X1 is N then 1~2 is SRl, Q represents S or Nl~1, in which 1~l is as de~ined above, R3 reprëtsents an amino yroup or 5R1 in which Rl is as defined above, and, Each R4 independently represents Rl as defined above or a halogen atom, a nitro moiety, a cyano moiety, or an alkoxycarbonyl group of 1 to 5 carbon atoms, the emulsions being free from contrast-promoting amounts of hydra2ine derivatives.
Rl is preferably a hydrogen atom or a methyl group, R2 is preferably a hydrogen atom or SH, xl is preferably N, -CH, -CCH3 or -CN02, R3 is preferably SH, SCH3 or NH2, and, R4 is preferably hydrogen.
The invention provides a negative-acting photosensitive silver halide material which may ~e used to obtain black and white half tone, line or dot images for photolithographic purposes. The element preferably comprises a support, having one or more hydrophilic colloidal layers located thereon, in which at least one layer comprises a fine grain, high chloride content and Group VIII metal doped photographic emulsion associated with one or more speed and contrast promoting agents selected from compounds of general formulae (i) to (iv).
The speed and contrast promoting agents need not be present in the emulsion during imaging, but must be associated with the emulsion during development. Thus, the compounds of general formulae (i) to (iv) may be introduced in to the emulsion from a treatment bath or the developer solution. The compounds may be present in the photographic element during imaging and optionally additional compounds present in the developer solution.
Examples of compounds suitable for inclusion as speed or contrast promoting agents are:
H2N ~ (B) C / C
~ N ~ 5CIl~ ~ SH
~C) / < H
Hzl~l S
( E ~ H C--C, ~ C / ~ l`l 5 ~G) ~ ~ (H) 11 ~c~c ~\
~C ~; '`I I-IIC ~ //
1~
..... ..
c I ~c--s ~ 1 l2 I'C`C'~ --5 ~ i --S
2 ~
Preferably the fine grain, hiyh chloride content and Group VIII metal doped photographic emulsion is associated with one or more speed and contrast promotin~
agents selected from compounds A to E.
Conventional sulphur and ~old sensitisation is known to confer some extra speed and contrast on these high chloride content rhodium dope~ photographic emulsions but compounds selected from general formulae (i) to (iv) yield greater speed and contrast increases than conventional sensitisation methods and can be used in combination with or without a chemical sensitisation step.
After image wise exposure of the fine grain, high chloride content rhodium doped silver halide emulsion, the material undergoes a photographic processiny step comprising an alkaline developing solution wherein the speed and contrast promoting agent is reactively associated with the emulsion. In a Eurther embodiment it is also possible to introduce the speed and contrast promoting agent in the developer solution followed by conventional washing or fixing but it is pre~erred that the agents are introduced as a precoating addition.
The term fine grain is used in the context of the present invention to reEer to silver halide grains having an average grain size of not more than 0.2 ~m.
High chloride content refers to the emulsion having at least 60% and preferably at least ~0% of its total halide molar content consisting of chloride ions. The emulsion is preferably a chlorobromide emulsion wherein the remainder of the halide content comprises bromide ions and a most preferred emulsion comprises ~4% silver chloride : 16% silver bromide having a mean silver halide grain size of O.O9~m.
The term Group VIII metal doped reEers to the process whereby during precipitation or physical ripenin~
o~ the silver halide emulsion, salts of one or more Group VIII metals, e.g., trisodium hexachlororllodate (III), disodium pentachlororuthenate (III) and tripotassium hexachloroiridate (III) are present in the solution. The preferred dopants are water-soluble trivalent salts of rhodium. The speed and contrast increasiny effect oE the compounds of general ~ormulae (i) to (iv) is directly proportional to the level oE dopant. The level of doping may be from 10-6 to 10-2 moles Group VIII metal salt per mole of silver but preferably is from 10-4 to 10-2 moles Group VIII metal salt per mole of silver and most preferably from 10 3 to 10 2 mole Group VIII metal salt per mole of silver.
The amount of the speed an~ contrast promotiny a~ent added is in the ranye 10-4 to 10~1 mole of ayent per mole of silver halide but preferably in the range lo~2 to 5 x 10-2 mole of ayent per mole of silver halide.
15 The invention will now be described with reference to the following Examples:
~ MPLE 1 PreDaration of a Rhodium Doped Silver llalide Emulsion A silver halide emulsion oE ~4 mole % chloride and 16 mole % bromide was prepared by the simultaneous addition under constant ayitation of water solution B and water Solution C by the double jet technique over a period of 25 minutes to water yelatin Solution A. The compositions A to C were:
Solution ~
Water 83~.3y Gelatin 25g Polyvinylpyrrolidone (K-30) 6.33y KBr 0.-167ml (lN) Solution B
Water 368y AgN03 170g Solution C
Water 361.3g KC1 62.65y (0.84 moles) ~Br 19.04y (0.16 moles) Na3RhC16-12~l20 0.200g ': :
` f, i, c~
The water gelatin Solution A was kept at a constant temperature of 40C. Solution B was added at a constant addition rate whilst the addition rate of Solution C was varied to maintain the potential of the emulsion thus formed at a value of 120 + 5mV (as measured with a specific electrode for Br ions and a re~erence electrode of the saturated Ag/AgCl type). The emulsion so prepared, following the removal of soluble salts by the conventional coagulation method, had a mean grain diameter of O.O9~m. The emulsion was then chemically sensitised with sodium gold chloride and sodium thiosulphate. At the end of the chemical sensitisation a speed and contrast promoting agent selected from compounds A to F, H or J in a suitable solvent was added to the emulsion before preparation for coating with the addition of additional gelatin, coating surface active agents and formaldehyde hardener.
The emulsion was coated at a silver coating weight of 2.7g Ag~m2 onto a polyester support base which was backed with a red antihalation layer.
The resulting films were exposed through a 0-2, 2Ocm continuous wedge. The exposing lamp was a Violux 1500S
UV lamp at a distance of 52 inches from the film plane.
The exposed films were developed in 3M RDCTM developer for 20 seconds Q 40C and fixed in 3M Fix RollTM Fixer.
J
The sensitometric data obtailled from silver halide coatinys made with compounds ~ to F are illustrated in Table 1 below.
TA~LE 1 Sensitometric Data for_Films Containinq Representative Examples Added ** Relative Contrast ~ Exposure*
Amount of Speed C~x~r~ (Log E) A C
(m le/mole _ _ None _ _ 0.11 _ _ 200 None _ -4.43 1.260.4 _ 2000 20 A 10-2 -3.46 5.1 1.5 6.0 200 ~ 2.5x10-3 -3.52 5.21.23 6.5 200 25 C 1o~2 ~3 53 3.61.27 5.4 200 D lo~2 -3.50 4.21.35 5.4 200 ~ lo~2 -3.60 5.31.44 6.5 200 30 ~ l 1o~2 1 -~ 73 1 2.~1 0.95 12.3 * Exposure on a Violux UV lamp (as described previously) ** Generally the amount added to give maximum effect is listed.
Contrast A is measured between densities 0.07 and 40 0.17 above Dmin.
Contrast C is measured between densities 0.5 and 2.5 above Dmin.
Each of compounds A to F were dissolved in an appropriate solvent and added at varying levels as a precoating addition to the emulsion. The emulsion used had the composition described previously and had been chemically sensitised with conventional sulphur and cJold compounds~ When no speed and contrast enhancing compound is added and with conventional exposure and processiny the film shows little developmellt, only Oll extremely long exposures to UV light does any density build up.
~owever, when the compounds of the invention are added, then a dramatic speed and contrast increase is seen.
EX~MPL~ Z
Effect of Varvinq the llalide Ratio of the Emulsion An alternative to the emulsion composition described in Example 1 was tested with Compound A. The emulsion was made following the protocol described previously except the halide ratio was altered ~rom 84 : 16 chloride to bromide to 96 : 4. Very similar results were observed 0 with increases in both speed and contrast.
EX~MPL~ 3 Effect of ComPound A as a DeveloPer Addition Some digested emulsion (composition as per Example 1) was coated in the standard ~ashion with no addition of any of the speed or contrast promoting agents. The ~ilm was given the standard exposure and processed in RDC
developer having some of compound A added. Washing and fixing were carried out in a conventional ~ashion.
At high levels of A, boosts in speed and contrast were observed but greater eEEects were noticed when A was added as a precoating addition.
` 2 ~
~X~Ml~L~ ~
Effect of ~arvinq the Rhodium Do~ant Level in the ~mulsion To investigate whetl~er the eEEect of the compounds oE
the present invention was also a function of the rhodium dopant level in the emulsion the followiny emulsions were made and coated as described below:
Emulsion 1 as detailed previously for ~xample 1.
Emulsion 2 exactly the same as Emulsion 1 except 0.0421g of Na3RhC16.12ll20 was used.
Emulsion 3 exactly the same as ~mulsion 1 except 4.21X10-3g of Na3RhC16.12H20 was used.
,, Emulsion ~ exactly the same as ~mulsion 1 except that no rhodium was used.
The exposure was varied depending on the speed oE the coated emulsions. The greater the level of rhodium, the slower the film is and hence, a greater exposure period is required. Emulsion 4 was found to be too East to be exposed by the Violux UV lamp so exposure was conducted with a quartz lamp.
For each emulsion, Eour coatings were made as described in Table 2.
TA~LE 2 Coating Chemically Compound A*
Design Digested ., I No No II -Yes No III No Yes IV Yes Yes ..
*400ml per mole oE a 0.325% solution of Compound A.
The following Tables sllow the increase in speed (measured at a density oE 1), toe and shoulder contrast (measured between 0.07 and 0.17 alld 0.5 and 2.5 above Dmin respectively) that occurred on addition oE Compound A Eor undigested and chemically sensitised emulsions ~i.e. sulphur and gold sensitised).
T~LF 3 Increase in sPeed (loqE~ on addition oE ComPound A
Chemica: L Sensitisation Emulsion No Yes 1 * + 0.78 highest level Z0 oE rhodium 2 * ~ 0.55 3 +0.8 + 0.5 1 4 I +0.07 ¦ + 0.4 no rhodium *In these cases the coatinys oE the undiyested emulsion with no Compound ~ were too slow to be measured usiny the same ex~osure level. For emulsion 1 the speed.increase is estimated to be > 210gE Eor the undigested emulsion.
rrl~ULE "
Increase in toe contrast (OAL
on addition of Compound ~
Chemical Sensitlsatlon Emulsion No .Yes . 1 * -~2.0 2 * +1.1 3 +0.7 +0.5 4 l0.15 ~0.14 _ T~LE 5 Increase in shoulder contrast (C~ on addition of ComPound A
. Chemical Sensitisation _ Emulsion NO YQS
1 * +9.8 2 * +6.0 3 +2.9 +3.2 4 +0.6 +0.6 .~
~r~LE 6 Increase in sPeed (loqE) on Chemical Sensitisation ¦ Compound A
Emulsion ¦ None Added as a l precoating final 1 _ +0.2 2 _ ~0.2 3 +0.6 +0.3 4 +0.4 +0.72 From Tables 3 - 6 it can be seen that the addition of Compound A causes a large increase in speed to both - undigested and chemically sensitised emulsions. The effect is greater for the undigested emulsion and or emulsions containing the higher levels of rhodium dopant.
....... - - .
2 ~
The same observations hold Eor the toe and shoulder contrasts ~Table 4 and Table 5 respectively).
Table 6 shows the increase in speed (logE) observed on chemical se~sitisation when Compound A is added as a precoating addition or not added at all. It can be seen that with no Compound A present, digestion gives a greater increase in speed with increasiny levels o~
rhodium dopant, when Compound A is added as a final the effect of chemical sensitisation decreases with increasing rhodium dopant level i.e. at higher rhodium levels most of the speed increase comes Erom the ad~ition of Compound A, the digestion step only gives a small further speed increase.
EX~Ml~L~ 5 ~ffect of various GrouP VIII do~ants An emulsion similar to that in Example l was preparecl except that the halide ratio was adjusted so that it was 96 mole % chloride 4% bromide emulsion.
Seven emulsions were prepared with the following levels of Group VIII transition metal dopants.
Emulsion 1 no dopant.
Emulsion 2 Na3RhC1612H20 0.014g per mole of silver.
10 Emulsion 3 Na3RhCl612~l20 O.l~y per mole o~ silver.
Emulsion 4 Na2[RUC15~ll2)] 0 0093CJ per mole o~ silver.
Emulsion 5 Na2[RUC15(H2)] 0-093g per mole oE silver.
~mulsion 6 X3IrC16 0.013g per mole oE silver.
Emulsion 7 K3IrCl6 0.13y per mole of silver.
15 Once prepared the emulsion was washed and chemically sensitised in the same way as in Example l. Compound A
was then added at a level oE 1.95g per mole of silver.
The emulsion was then coated onto clear subbed polyester with the conventional coating aids and hardeners at a coating weight of 2.5g Ay/m2.
~` 2~1Pj3 The resulting films were exposed through a 0-4 lOcm continuous wedge. The exposing source was a Thiemer Spektra Proof Daylight containing a l~W ThlO07 polymer bulb. The exposed $ilms were developed in 3M RDC
developer for 30 seconds at 350C and Eixed in 3M Fix Roll fixer.
The sensitometric data obtained are given in Table 7. Two different coatings of each emulsion were made using the following design:
Type Chemical Compound A
15 Sensitisation i) yes absent ii) yes present 17 ~ ;3 ~
_ 5 E~sion Type Rel. speed Maximum I Contrast E~x~ure/
_ /log E ~ity Units 1 i) 3.1 4.2 4.5 1 ii~ 3.2 4.2 5.3 2 i) 1.9 4.4 4.6 4 3 iii) 2 2 1 ~ 12 2 4 ii) .9 4.2 9.3 4 .' 4 i) 2.6 2.7 0.7 4 ii) 2.9 4.2 5.6 4 ~5 5 i) 1.2 1.3 _ 4 ii) 1.4 4.2 2.4 4 6 i) 2.6 4.4 4.8 4 ii) 2.7 4.4 6.7 4 7 i) 1.8 3.4* 4.8 4 35 l ~ 1 2.1 4.3 1 6.7 4 * Strong solarisation noticed.
Speed measured at 1.00 above Eoy.
Contrast measured between 0. 5 and 2. 5 above fog.
Comparison o~ the results for the rhodium doped Emulsions 2 and 3 with the undoped Emulsion 1 show the significant effect of Compound A. Improvements in speed and contrast are obtained, the maynitude o~ the improvement related directly to the level o~ rhodium dopant. A large increase in maximum density is also observed for Emulsion 3. They also show the overall desensitisation effect of rhodium.
For the ruthenium doped E:mulsions 4 and 5 improvements in speed and, especially, contrast and maximum density are agaill obtained on addition o~
Compound A.
1~
Emulsions 6 and 7 show the eE~ect o~ iridium doping.
There is an overall desensitisation related to the level of dopant (see li) 6i) and 7i). On addition of Compound A speed, contrast and for the heavily doped emulsion maximum density are increased. For Emulsion 7 solarisation is also observed which is eliminated on addition of Compound A.
This invention relates to negative~acting silver halide photographic materials and in particular to photographic elements comprising Group VIII metal doped silver halide emulsions associated with a speed and contrast promoting agent which are suitable for use in the photolithographic printing industry and for the development of daylight handleable contact film.
Photosensitive silver halide materials are commonly used in the photolithographic industry to obtain half tone, dot or line, high contrast images.
To increase the contrast of lithographic films it is common practice to dope the silver halide emulsions with contrast promoting agents, among which are the water soluble Group VIII metal salts, such as the trivalent salts of rhodium, ruthenium and iridium. It is known that good results as regards high covering power (which is the ratio between the maximum density obtained after development and the silver halide coverage) and rapid developability (for productivity increase) can be obtained by using fine grained (less than 0.15 ~m) and high chloride content silver halide emulsions. It is known that such emulsions which contain a Group VIII
metal as a contrast promoting agent may still not have - 25 the required contrast, and as the dopant desensitises the emulsion, it may not have the required speed.
One approach to the development of a daylight handleable contact film has been to modify existing -daylight duplicating film. Contact films are negative acting materials which are exposed in contact with an original to record a negative image of the original.
Duplicating films are positive acting materials which are exposed in contact with an original to produce an identical copy. To produce a duplicating film, the emulsion is chemically fogged, a metal dopant such as rhodium being required for the reversal process as well as for desensitising purposes. For a contact film, the unfogged duplicating emulsion is far too slow for practical use, primarily due to the level of dopant. As stated previously it is advantageous to have the dopant present for contrast enhancement purposes but to increase the speed and also contrast to usable levels a sensitisation step must be introduced. Conventional gold and sulphur sensitisation does confer some extra speed and contrast but European Patent Applications Nos. 267598 and 138200 and British Patent Applications Nos. 2202341 and 2206700 disclose negative-acting rhodium doped emulsions in which the contrast is enhanced by addition of a hydrazine derivative. Such materials are generally too sensitive to be daylight-handleable, and if this property is required, a desensitiser must be added.
Various examples of the latter are disclosed, including 2-mercaptobenzimidazole derivatives.
British Patent No. 741228 discloses the use of 4-substituted 3-amino-5-mercapto-4,1,2-triazoles of general formula (I) (I) ~- ~ -H ~ IN 2 in which:
R represents other than H, in photographic constructions. The compounds of formula (I) are said to restrain the formation of chemical fog without seriously affecting the speed, contrast or other properties of the emulsion.
British Patent No. 2573027 discloses the use of compounds of general formulae (II) and (III) ( Cl ) ~(, C~ N
, 35 ~ l NH
S H y ~ ~ / S
, b;9 a~ ~ ~
in whicb:
X represents 0 or S, Y represents 0, S or NH, and, D represents substituted or unsubstituted carbon atoms to complete a 6 membered ring, in a photographic construction as anti-bronzing agents.
However, within the patent there is no mention of doping of the emulsions.
U.S. Patent No. 1,725,934 discloses the use of thiazole derivatives in silver halide constructions, but as an anti-fogging agent.
The combination of a triazole (IVa) and tetrazaindene (IVb) is known in the photographic art to act as a stabiliser.
(nUb) (l~
H~ ~ ~ ~ N c ~ \
C ---SC 1~3 ¦ I~ H
H0~2C~
0ll 5C~3 It has now been found that certain groups of compounds, some of which have previously been used as desensitisers, antifoggants, anti-bronzing agents or stabilisers, have a particular utility as speed and contrast promoting agents in Group VIII metal doped, negative-acting silver halide emulsions, the emulsions being chemically-sensitised or otherwise, and being free from contrast-promoting amounts of hydrazine derivatives.
According to one aspect of the present invention there is provided a photographic element comprising a Group VIII metal doped negative-acting silver halide emulsion characterised in that the emulsion is associated with one or more speed and contrast promoting agents comprising a compound having a nucleus of one of the following general formulae (i) to (iv) :
t ~, ! ~ . ,:;, ` ~ ~ '~' '` ' 4 ~ 'J iL ~
(i3 ~ ) N~X
C/ ~C~SI ~ N/ --S/
, (;" ) R4 (1~) R ~ ~1 R~C~C:~C/3 3 ~C// ~N.llcl -~4~ ~C~ C~ 2~ . 5 in which:
Each Rl independently represents a hydrogen atom or an alkyl group of 1 to 5 carbon atoms, op~ionally having one or more substituents selected Erom hydroxyl moieties, carboxyl moieties, alkoxy carbonyl yroups of 1 to 5 carbon atoms,.cyano moieties, halogen atoms, nitro moieties, amino moieties and aryl CJrOUpS O~ Up to 10 carbon atoms, wherein the aryl yroup may be optionally substituted with one or more substituents selected from alkyl groups of 1 to 5 carbon atoms, hydroxyl moieties, carboxyl moieties, alkoxy carbonyl yroups oE 1 to 5 carbon atoms, cyano moieties, llaloyen atoms, nitro moieties and amino moieties, Xl represents N or CR5, where R5 represents Rl (as defined above) or N02, R2 represents a hydroyen atom or SR1 (Rl is as '35 defined,,above) but if X1 is N then 1~2 is SRl, Q represents S or Nl~1, in which 1~l is as de~ined above, R3 reprëtsents an amino yroup or 5R1 in which Rl is as defined above, and, Each R4 independently represents Rl as defined above or a halogen atom, a nitro moiety, a cyano moiety, or an alkoxycarbonyl group of 1 to 5 carbon atoms, the emulsions being free from contrast-promoting amounts of hydra2ine derivatives.
Rl is preferably a hydrogen atom or a methyl group, R2 is preferably a hydrogen atom or SH, xl is preferably N, -CH, -CCH3 or -CN02, R3 is preferably SH, SCH3 or NH2, and, R4 is preferably hydrogen.
The invention provides a negative-acting photosensitive silver halide material which may ~e used to obtain black and white half tone, line or dot images for photolithographic purposes. The element preferably comprises a support, having one or more hydrophilic colloidal layers located thereon, in which at least one layer comprises a fine grain, high chloride content and Group VIII metal doped photographic emulsion associated with one or more speed and contrast promoting agents selected from compounds of general formulae (i) to (iv).
The speed and contrast promoting agents need not be present in the emulsion during imaging, but must be associated with the emulsion during development. Thus, the compounds of general formulae (i) to (iv) may be introduced in to the emulsion from a treatment bath or the developer solution. The compounds may be present in the photographic element during imaging and optionally additional compounds present in the developer solution.
Examples of compounds suitable for inclusion as speed or contrast promoting agents are:
H2N ~ (B) C / C
~ N ~ 5CIl~ ~ SH
~C) / < H
Hzl~l S
( E ~ H C--C, ~ C / ~ l`l 5 ~G) ~ ~ (H) 11 ~c~c ~\
~C ~; '`I I-IIC ~ //
1~
..... ..
c I ~c--s ~ 1 l2 I'C`C'~ --5 ~ i --S
2 ~
Preferably the fine grain, hiyh chloride content and Group VIII metal doped photographic emulsion is associated with one or more speed and contrast promotin~
agents selected from compounds A to E.
Conventional sulphur and ~old sensitisation is known to confer some extra speed and contrast on these high chloride content rhodium dope~ photographic emulsions but compounds selected from general formulae (i) to (iv) yield greater speed and contrast increases than conventional sensitisation methods and can be used in combination with or without a chemical sensitisation step.
After image wise exposure of the fine grain, high chloride content rhodium doped silver halide emulsion, the material undergoes a photographic processiny step comprising an alkaline developing solution wherein the speed and contrast promoting agent is reactively associated with the emulsion. In a Eurther embodiment it is also possible to introduce the speed and contrast promoting agent in the developer solution followed by conventional washing or fixing but it is pre~erred that the agents are introduced as a precoating addition.
The term fine grain is used in the context of the present invention to reEer to silver halide grains having an average grain size of not more than 0.2 ~m.
High chloride content refers to the emulsion having at least 60% and preferably at least ~0% of its total halide molar content consisting of chloride ions. The emulsion is preferably a chlorobromide emulsion wherein the remainder of the halide content comprises bromide ions and a most preferred emulsion comprises ~4% silver chloride : 16% silver bromide having a mean silver halide grain size of O.O9~m.
The term Group VIII metal doped reEers to the process whereby during precipitation or physical ripenin~
o~ the silver halide emulsion, salts of one or more Group VIII metals, e.g., trisodium hexachlororllodate (III), disodium pentachlororuthenate (III) and tripotassium hexachloroiridate (III) are present in the solution. The preferred dopants are water-soluble trivalent salts of rhodium. The speed and contrast increasiny effect oE the compounds of general ~ormulae (i) to (iv) is directly proportional to the level oE dopant. The level of doping may be from 10-6 to 10-2 moles Group VIII metal salt per mole of silver but preferably is from 10-4 to 10-2 moles Group VIII metal salt per mole of silver and most preferably from 10 3 to 10 2 mole Group VIII metal salt per mole of silver.
The amount of the speed an~ contrast promotiny a~ent added is in the ranye 10-4 to 10~1 mole of ayent per mole of silver halide but preferably in the range lo~2 to 5 x 10-2 mole of ayent per mole of silver halide.
15 The invention will now be described with reference to the following Examples:
~ MPLE 1 PreDaration of a Rhodium Doped Silver llalide Emulsion A silver halide emulsion oE ~4 mole % chloride and 16 mole % bromide was prepared by the simultaneous addition under constant ayitation of water solution B and water Solution C by the double jet technique over a period of 25 minutes to water yelatin Solution A. The compositions A to C were:
Solution ~
Water 83~.3y Gelatin 25g Polyvinylpyrrolidone (K-30) 6.33y KBr 0.-167ml (lN) Solution B
Water 368y AgN03 170g Solution C
Water 361.3g KC1 62.65y (0.84 moles) ~Br 19.04y (0.16 moles) Na3RhC16-12~l20 0.200g ': :
` f, i, c~
The water gelatin Solution A was kept at a constant temperature of 40C. Solution B was added at a constant addition rate whilst the addition rate of Solution C was varied to maintain the potential of the emulsion thus formed at a value of 120 + 5mV (as measured with a specific electrode for Br ions and a re~erence electrode of the saturated Ag/AgCl type). The emulsion so prepared, following the removal of soluble salts by the conventional coagulation method, had a mean grain diameter of O.O9~m. The emulsion was then chemically sensitised with sodium gold chloride and sodium thiosulphate. At the end of the chemical sensitisation a speed and contrast promoting agent selected from compounds A to F, H or J in a suitable solvent was added to the emulsion before preparation for coating with the addition of additional gelatin, coating surface active agents and formaldehyde hardener.
The emulsion was coated at a silver coating weight of 2.7g Ag~m2 onto a polyester support base which was backed with a red antihalation layer.
The resulting films were exposed through a 0-2, 2Ocm continuous wedge. The exposing lamp was a Violux 1500S
UV lamp at a distance of 52 inches from the film plane.
The exposed films were developed in 3M RDCTM developer for 20 seconds Q 40C and fixed in 3M Fix RollTM Fixer.
J
The sensitometric data obtailled from silver halide coatinys made with compounds ~ to F are illustrated in Table 1 below.
TA~LE 1 Sensitometric Data for_Films Containinq Representative Examples Added ** Relative Contrast ~ Exposure*
Amount of Speed C~x~r~ (Log E) A C
(m le/mole _ _ None _ _ 0.11 _ _ 200 None _ -4.43 1.260.4 _ 2000 20 A 10-2 -3.46 5.1 1.5 6.0 200 ~ 2.5x10-3 -3.52 5.21.23 6.5 200 25 C 1o~2 ~3 53 3.61.27 5.4 200 D lo~2 -3.50 4.21.35 5.4 200 ~ lo~2 -3.60 5.31.44 6.5 200 30 ~ l 1o~2 1 -~ 73 1 2.~1 0.95 12.3 * Exposure on a Violux UV lamp (as described previously) ** Generally the amount added to give maximum effect is listed.
Contrast A is measured between densities 0.07 and 40 0.17 above Dmin.
Contrast C is measured between densities 0.5 and 2.5 above Dmin.
Each of compounds A to F were dissolved in an appropriate solvent and added at varying levels as a precoating addition to the emulsion. The emulsion used had the composition described previously and had been chemically sensitised with conventional sulphur and cJold compounds~ When no speed and contrast enhancing compound is added and with conventional exposure and processiny the film shows little developmellt, only Oll extremely long exposures to UV light does any density build up.
~owever, when the compounds of the invention are added, then a dramatic speed and contrast increase is seen.
EX~MPL~ Z
Effect of Varvinq the llalide Ratio of the Emulsion An alternative to the emulsion composition described in Example 1 was tested with Compound A. The emulsion was made following the protocol described previously except the halide ratio was altered ~rom 84 : 16 chloride to bromide to 96 : 4. Very similar results were observed 0 with increases in both speed and contrast.
EX~MPL~ 3 Effect of ComPound A as a DeveloPer Addition Some digested emulsion (composition as per Example 1) was coated in the standard ~ashion with no addition of any of the speed or contrast promoting agents. The ~ilm was given the standard exposure and processed in RDC
developer having some of compound A added. Washing and fixing were carried out in a conventional ~ashion.
At high levels of A, boosts in speed and contrast were observed but greater eEEects were noticed when A was added as a precoating addition.
` 2 ~
~X~Ml~L~ ~
Effect of ~arvinq the Rhodium Do~ant Level in the ~mulsion To investigate whetl~er the eEEect of the compounds oE
the present invention was also a function of the rhodium dopant level in the emulsion the followiny emulsions were made and coated as described below:
Emulsion 1 as detailed previously for ~xample 1.
Emulsion 2 exactly the same as Emulsion 1 except 0.0421g of Na3RhC16.12ll20 was used.
Emulsion 3 exactly the same as ~mulsion 1 except 4.21X10-3g of Na3RhC16.12H20 was used.
,, Emulsion ~ exactly the same as ~mulsion 1 except that no rhodium was used.
The exposure was varied depending on the speed oE the coated emulsions. The greater the level of rhodium, the slower the film is and hence, a greater exposure period is required. Emulsion 4 was found to be too East to be exposed by the Violux UV lamp so exposure was conducted with a quartz lamp.
For each emulsion, Eour coatings were made as described in Table 2.
TA~LE 2 Coating Chemically Compound A*
Design Digested ., I No No II -Yes No III No Yes IV Yes Yes ..
*400ml per mole oE a 0.325% solution of Compound A.
The following Tables sllow the increase in speed (measured at a density oE 1), toe and shoulder contrast (measured between 0.07 and 0.17 alld 0.5 and 2.5 above Dmin respectively) that occurred on addition oE Compound A Eor undigested and chemically sensitised emulsions ~i.e. sulphur and gold sensitised).
T~LF 3 Increase in sPeed (loqE~ on addition oE ComPound A
Chemica: L Sensitisation Emulsion No Yes 1 * + 0.78 highest level Z0 oE rhodium 2 * ~ 0.55 3 +0.8 + 0.5 1 4 I +0.07 ¦ + 0.4 no rhodium *In these cases the coatinys oE the undiyested emulsion with no Compound ~ were too slow to be measured usiny the same ex~osure level. For emulsion 1 the speed.increase is estimated to be > 210gE Eor the undigested emulsion.
rrl~ULE "
Increase in toe contrast (OAL
on addition of Compound ~
Chemical Sensitlsatlon Emulsion No .Yes . 1 * -~2.0 2 * +1.1 3 +0.7 +0.5 4 l0.15 ~0.14 _ T~LE 5 Increase in shoulder contrast (C~ on addition of ComPound A
. Chemical Sensitisation _ Emulsion NO YQS
1 * +9.8 2 * +6.0 3 +2.9 +3.2 4 +0.6 +0.6 .~
~r~LE 6 Increase in sPeed (loqE) on Chemical Sensitisation ¦ Compound A
Emulsion ¦ None Added as a l precoating final 1 _ +0.2 2 _ ~0.2 3 +0.6 +0.3 4 +0.4 +0.72 From Tables 3 - 6 it can be seen that the addition of Compound A causes a large increase in speed to both - undigested and chemically sensitised emulsions. The effect is greater for the undigested emulsion and or emulsions containing the higher levels of rhodium dopant.
....... - - .
2 ~
The same observations hold Eor the toe and shoulder contrasts ~Table 4 and Table 5 respectively).
Table 6 shows the increase in speed (logE) observed on chemical se~sitisation when Compound A is added as a precoating addition or not added at all. It can be seen that with no Compound A present, digestion gives a greater increase in speed with increasiny levels o~
rhodium dopant, when Compound A is added as a final the effect of chemical sensitisation decreases with increasing rhodium dopant level i.e. at higher rhodium levels most of the speed increase comes Erom the ad~ition of Compound A, the digestion step only gives a small further speed increase.
EX~Ml~L~ 5 ~ffect of various GrouP VIII do~ants An emulsion similar to that in Example l was preparecl except that the halide ratio was adjusted so that it was 96 mole % chloride 4% bromide emulsion.
Seven emulsions were prepared with the following levels of Group VIII transition metal dopants.
Emulsion 1 no dopant.
Emulsion 2 Na3RhC1612H20 0.014g per mole of silver.
10 Emulsion 3 Na3RhCl612~l20 O.l~y per mole o~ silver.
Emulsion 4 Na2[RUC15~ll2)] 0 0093CJ per mole o~ silver.
Emulsion 5 Na2[RUC15(H2)] 0-093g per mole oE silver.
~mulsion 6 X3IrC16 0.013g per mole oE silver.
Emulsion 7 K3IrCl6 0.13y per mole of silver.
15 Once prepared the emulsion was washed and chemically sensitised in the same way as in Example l. Compound A
was then added at a level oE 1.95g per mole of silver.
The emulsion was then coated onto clear subbed polyester with the conventional coating aids and hardeners at a coating weight of 2.5g Ay/m2.
~` 2~1Pj3 The resulting films were exposed through a 0-4 lOcm continuous wedge. The exposing source was a Thiemer Spektra Proof Daylight containing a l~W ThlO07 polymer bulb. The exposed $ilms were developed in 3M RDC
developer for 30 seconds at 350C and Eixed in 3M Fix Roll fixer.
The sensitometric data obtained are given in Table 7. Two different coatings of each emulsion were made using the following design:
Type Chemical Compound A
15 Sensitisation i) yes absent ii) yes present 17 ~ ;3 ~
_ 5 E~sion Type Rel. speed Maximum I Contrast E~x~ure/
_ /log E ~ity Units 1 i) 3.1 4.2 4.5 1 ii~ 3.2 4.2 5.3 2 i) 1.9 4.4 4.6 4 3 iii) 2 2 1 ~ 12 2 4 ii) .9 4.2 9.3 4 .' 4 i) 2.6 2.7 0.7 4 ii) 2.9 4.2 5.6 4 ~5 5 i) 1.2 1.3 _ 4 ii) 1.4 4.2 2.4 4 6 i) 2.6 4.4 4.8 4 ii) 2.7 4.4 6.7 4 7 i) 1.8 3.4* 4.8 4 35 l ~ 1 2.1 4.3 1 6.7 4 * Strong solarisation noticed.
Speed measured at 1.00 above Eoy.
Contrast measured between 0. 5 and 2. 5 above fog.
Comparison o~ the results for the rhodium doped Emulsions 2 and 3 with the undoped Emulsion 1 show the significant effect of Compound A. Improvements in speed and contrast are obtained, the maynitude o~ the improvement related directly to the level o~ rhodium dopant. A large increase in maximum density is also observed for Emulsion 3. They also show the overall desensitisation effect of rhodium.
For the ruthenium doped E:mulsions 4 and 5 improvements in speed and, especially, contrast and maximum density are agaill obtained on addition o~
Compound A.
1~
Emulsions 6 and 7 show the eE~ect o~ iridium doping.
There is an overall desensitisation related to the level of dopant (see li) 6i) and 7i). On addition of Compound A speed, contrast and for the heavily doped emulsion maximum density are increased. For Emulsion 7 solarisation is also observed which is eliminated on addition of Compound A.
Claims (12)
1. A photographic element comprising a Group VIII metal doped negative-acting silver halide emulsion characterised in that the emulsion is associated with one or more speed and contrast promoting agents comprising a compound having a nucleus of one of the following general formulae: (i) to (iv) (i) (ii) (iii) (iv) in which:
Each R1 independently represents a hydrogen atom or an alkyl group of 1 to 5 carbon atoms, optionally having one or more substituents selected from hydroxyl moieties, carboxyl moieties, alkoxy carbonyl groups of 1 to 5 carbon atoms, cyano moieties, halogen atoms, nitro moieties, amino moieties and aryl groups of up to 10 carbon atoms, wherein the aryl group may be optionally substituted with one or more substituents selected from alkyl groups of 1 to 5 carbon atoms, hydroxyl moieties, carboxyl moieties, alkoxy carbonyl groups of 1 to 5 carbon atoms, cyano moieties, halogen atoms, nitro moieties and amino moieties,
Each R1 independently represents a hydrogen atom or an alkyl group of 1 to 5 carbon atoms, optionally having one or more substituents selected from hydroxyl moieties, carboxyl moieties, alkoxy carbonyl groups of 1 to 5 carbon atoms, cyano moieties, halogen atoms, nitro moieties, amino moieties and aryl groups of up to 10 carbon atoms, wherein the aryl group may be optionally substituted with one or more substituents selected from alkyl groups of 1 to 5 carbon atoms, hydroxyl moieties, carboxyl moieties, alkoxy carbonyl groups of 1 to 5 carbon atoms, cyano moieties, halogen atoms, nitro moieties and amino moieties,
2 X1 represents N or CR4, where R4 represents R1 (as defined above) or NO2, R2 represents a hydrogen atom or SR1 (R1 is as defined above) but if X1 is N then R2 is SR1, Q represents S or NR1 in which R1 is as defined above, R3 represents an amino group or SR1 in which R1 is as defined above, and, Each R4 independently represents R1 as defined above or a halogen atom, a nitro moiety, a cyano moiety, or an alkoxycarbonyl group of 1 to 5 carbon atoms, the emulsion being free from contrast-promoting amounts of hydrazine derivatives.
2. A photographic element as claimed in Claim 1 characterised in that the Group VIII metal dopant is rhodium.
2. A photographic element as claimed in Claim 1 characterised in that the Group VIII metal dopant is rhodium.
3. A photographic element as claimed in Claim 1 or Claim 2 characterised in that the speed and contrast promoting agent is a compound selected from:
and
and
4. A photographic element as claimed in any preceding claim characterised in that the silver halide emulsion comprises a support upon which is coated one or more hydrophilic colloidal layers in which at least one layer comprises a fine grain silver halide emulsion having an average grain size of not more than 0.2µm.
5. A photographic element as claimed in Claim 4 characterised in that the silver halide emulsion comprises a chlorobromide emulsion in which silver chloride comprises at least 60% of the total silver halide content.
6. A photographic element as claimed in any preceding claim characterised in that the speed and contrast promoting agent has a concentration of 10-4 to 10-1 moles per mole of silver halide.
7. A photographic element as claimed in any preceding Claim characterised in that the concentration of Group VIII metal dopant is from 10-5 to 10-2 moles dopant per mole of silver halide.
8. A photographic element as claimed in any preceding claim characterised in that the dopant comprises a water soluble trivalent rhodium salt.
9. A photographic element as claimed in any preceding Claim characterised in that the silver halide emulsion is sulphur and gold sensitised.
10. A photographic process which comprises image wise exposing a photographic element comprising a Group VIII
metal doped negative acting silver halide emulsion free from contrast-promoting amounts of hydrazine, developing and fixing said exposed element characterised in that one or more speed and contrast promoting agents is associated with the emulsion during development, said agent being selected from compounds having a nucleus of one of the general formulae:
(i) (ii) (iii) (iv) in which:
R1 to R4, X1 and Q are as defined in Claim 1.
metal doped negative acting silver halide emulsion free from contrast-promoting amounts of hydrazine, developing and fixing said exposed element characterised in that one or more speed and contrast promoting agents is associated with the emulsion during development, said agent being selected from compounds having a nucleus of one of the general formulae:
(i) (ii) (iii) (iv) in which:
R1 to R4, X1 and Q are as defined in Claim 1.
11. A photographic process as claimed in Claim 11 characterised in that the speed and contrast promoting agent:
(i) is present in the emulsion prior to exposure, and/or, (ii) is introduced into the emulsion after exposure, and/or, (iii) is present in the developer solution.
(i) is present in the emulsion prior to exposure, and/or, (ii) is introduced into the emulsion after exposure, and/or, (iii) is present in the developer solution.
12. A developing solution for a photographic element characterised in that the developing solution comprises one or more speed and contrast promoting agents of formula:
(i) (ii) (iii) (iv) in which:
R1 to R4, X1 and Q are as defined in Claim 1.
(i) (ii) (iii) (iv) in which:
R1 to R4, X1 and Q are as defined in Claim 1.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB898911453A GB8911453D0 (en) | 1989-05-18 | 1989-05-18 | Speed and contrast promoted silver halide rhodium doped emulsions |
| GB89.11453 | 1989-05-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2016495A1 true CA2016495A1 (en) | 1990-11-18 |
Family
ID=10656972
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2016495 Abandoned CA2016495A1 (en) | 1989-05-18 | 1990-05-10 | Speed and contrast promoted silver halide doped emulsions |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0398600B1 (en) |
| JP (1) | JPH036551A (en) |
| AU (1) | AU624946B2 (en) |
| CA (1) | CA2016495A1 (en) |
| DE (1) | DE69028801T2 (en) |
| GB (1) | GB8911453D0 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2336909C (en) | 1998-07-15 | 2009-10-20 | Teijin Limited | Thiobenzimidazole derivatives which are useful as inhibitors of human chymase activity |
| JP2012507530A (en) | 2008-10-29 | 2012-03-29 | メルク・シャープ・エンド・ドーム・コーポレイション | Novel cyclic benzimidazole derivatives that are useful anti-diabetic agents |
| JP5557845B2 (en) | 2008-10-31 | 2014-07-23 | メルク・シャープ・アンド・ドーム・コーポレーション | Novel cyclic benzimidazole derivatives useful as antidiabetic agents |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS495334A (en) * | 1972-04-28 | 1974-01-18 | ||
| DE3403825A1 (en) * | 1983-02-04 | 1984-08-16 | Mitsubishi Paper Mills, Ltd., Tokyo | Photographic light-sensitive silver halide materials |
| GB2190510B (en) * | 1986-04-02 | 1989-11-22 | Fuji Photo Film Co Ltd | Silver halide photographic material and image-forming method using the same |
| JPH0612406B2 (en) * | 1986-11-14 | 1994-02-16 | 富士写真フイルム株式会社 | Ultra-high contrast negative type silver halide photographic light-sensitive material |
| JPH01183643A (en) * | 1988-01-18 | 1989-07-21 | Fuji Photo Film Co Ltd | Silver halide color sensitive material |
-
1989
- 1989-05-18 GB GB898911453A patent/GB8911453D0/en active Pending
-
1990
- 1990-05-02 AU AU54632/90A patent/AU624946B2/en not_active Ceased
- 1990-05-10 CA CA 2016495 patent/CA2016495A1/en not_active Abandoned
- 1990-05-11 DE DE1990628801 patent/DE69028801T2/en not_active Expired - Fee Related
- 1990-05-11 EP EP90305114A patent/EP0398600B1/en not_active Expired - Lifetime
- 1990-05-17 JP JP12809990A patent/JPH036551A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPH036551A (en) | 1991-01-14 |
| AU5463290A (en) | 1990-11-22 |
| EP0398600B1 (en) | 1996-10-09 |
| GB8911453D0 (en) | 1989-07-05 |
| AU624946B2 (en) | 1992-06-25 |
| EP0398600A3 (en) | 1991-10-09 |
| EP0398600A2 (en) | 1990-11-22 |
| DE69028801D1 (en) | 1996-11-14 |
| DE69028801T2 (en) | 1997-04-10 |
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