US3782957A - Fogged,direct-positive silver halide emulsion layer containing a cyanine dye and a compound containing a metal of group viii of the periodic table - Google Patents

Fogged,direct-positive silver halide emulsion layer containing a cyanine dye and a compound containing a metal of group viii of the periodic table Download PDF

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Publication number
US3782957A
US3782957A US00213809A US3782957DA US3782957A US 3782957 A US3782957 A US 3782957A US 00213809 A US00213809 A US 00213809A US 3782957D A US3782957D A US 3782957DA US 3782957 A US3782957 A US 3782957A
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United States
Prior art keywords
light
silver halide
emulsion layer
dye
sensitive material
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Expired - Lifetime
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US00213809A
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English (en)
Inventor
K Ohkubo
T Masuda
K Shiba
A Ogawa
M Hinata
A Sato
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Fujifilm Holdings Corp
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Fuji Photo Film Co Ltd
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    • 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
    • G03C1/485—Direct positive emulsions
    • G03C1/48515—Direct positive emulsions prefogged
    • G03C1/48523—Direct positive emulsions prefogged characterised by the desensitiser
    • G03C1/4853—Direct positive emulsions prefogged characterised by the desensitiser polymethine dyes

Definitions

  • a direct reversal silver halide photographic material suitable for use in a copying process utilizing a mercury or fluorescent lamp is provided by including a compound of a metal of Group VIII of the Periodic Table and a specific cyanine dye in a silver halide emulsion layer.
  • the fog nuclei formed in the silver halide emulsion layer beforehand have resistance to indoor illumination, and the resultant photographic material can be handled under indoor illumination without causing the breakage of the fog nuclei, and gives images of good contrast.
  • Direct reversal silver halide photographic light-sensitive material This invention relates to a direct reversal silver halide light-sensitive material and, more particularly, to a direct reversal silver halide photographic light-sensitive material (hereinafter referred to merely as light-sensitive material) suitable for a copying method wherein a mercury lamp or a fluorescent lamp for copying is utilized.
  • the light-sensitive materials of this kind are called direct reversal photographic light-sensitive materials.
  • the light-sensitive material of this kind is often used as an intermediate original when many copies are prepared from blue copies such as a copy of diazo light-sensitive material or a blueprint. Images formed on the blue copies are, in the optical copying method, pretty low in contrast. It is not preferable to use the blue copies as originals for copying as such'since only copies of images low in contrast can be obtained. Therefore, the blue copies are once copied to a special light-sensitive material (i.e., special in its constitution and expensive too) to form images comon cheaper light-sensitive materials using the resulting in- 3,782,957 Patented Jan. 1, 1974 termediate image as an intermediate original.
  • a special light-sensitive material i.e., special in its constitution and expensive too
  • a mercury lamp or a fluorescent lamp which greatly emit light of long wavelength as well as light of short wavelength (the light of short wavelength being out off, for example, by using a yellow filter in order to increase the contrast at printing) is used as a light source. Since, the color of the images on an original is blue, which is comparatively high in light transmission, if light of short Wavelength strong in penetrating power is used as a light source for exposure, the emitted light transmits the image portions on the original to such an extent that contrast between the image portions and the non-image portions is low, and hence only images low in contrast can be formed in the copy obtained. Accordingly, among the light emitted fro-m a mercury lamp or a fluorescent lamp for copying, that of comparatively long Wavelength, mainly 5460 A. and 5770 A., which transmits through a yellow filter is used for the above described copying.
  • the sensitizing dyes such as cyanine dyes can be added thereto to color-sensitize, whereby the sensitivity to the light of long wavelength is raised.
  • the publicly known sensitizing dyes are not satisfactory to solve the above mentioned subject because, while they raise the sensitivity to light of long wavelength, in many cases, they also raise the sensitivity to light of short Wavelength at the same time.
  • no special treatment has been conducted as to the peak of the spectral sensitivity in the case of such light-sensitive materials.
  • the light-sensitive material exposed to a mercury lamp or a fluorescent lamp for copying should be high in the sensitivity to the bright lines of 5461 A. and 5770 A. in the long wavelength (both being the wave lengths at which the spectral distribution the bright lines of mercury is maximum) among the light (i.e., the bright line of mercury) emitted from these light sources for exposure, and low in sensitivity to light emitted from a fluorescent lamp used for lighting the room wherein the light-sensitive material is dealt with, mainly to the bright lines of 3660 A., 4047 A., and 4358 A. (these being the wavelengths at which the spectral distribution of the light emitted from a fluorescent lamp for room-lighting is maximum).
  • the object of the invention is to provide a direct reversal silver halide photographic light-sensitive material which is high in sensitivity to light of mainly 5461 A. and 5770 A. in the long wavelength, both being wavelengths at which the spectral distribution of bright lines of mercury emitted from a mercury lamp is maximum, and wherein the fog nuclei have resistance to breakage even when handled under a room-lighting fluorescent lamp, i.e.,
  • a direct reversal silver halide photographic material wherein a silver halide emulsion layer contains a compound of a metal of Group VIII of the periodic table and a dye represented by the following formula wherein L L and L, each represents a methine group, R and R each represents an alkyl group or substituted alkyl group usually used for cyanine dyes, R and R each represents alkyl, aralkyl or allyl group, X represents an anion, n represents an integer of 1 or 2, Z represents a goup of atoms necessary to complete a benzene or naphthalene ring, and Z represents a group of non metallic atoms necessary to complete an oxazole ring, and R and L and R and L respectively may
  • the silver halide emulsion employed in the invention is prepared by previously fogging a silver halide emulsion prepared in a usual manner by a exposure to light or by chemical process using, for example, compound such as aldehydes, hydrazines, stannous chloride, silver ion, thiourea dioxide, amineborane compounds, etc. either independently or in combination.
  • compound such as aldehydes, hydrazines, stannous chloride, silver ion, thiourea dioxide, amineborane compounds, etc. either independently or in combination.
  • any of silver chloride, silver chloroiodide, silver chlorobromide, silver bromide, silver bromoiodide and silver chlorobromoiodide will do.
  • the grain size thereof within the range employed in the usual silver halide emulsion is satisfactory, but a mean grain size smaller than 0.6 micron is particularly effective in the invention.
  • the silver halide grains may be regular or irregular grains, but regular grains bring about especially good results.
  • a monodispersed emulsion is more effective, but non-monodispersed emulsion is also satisfactory.
  • silver halied emulsions have incorporated therein with the compound (metal salt) containing a Group VIII metal of the periodic table, such as rhodium, ruthenium, iridium, osmium, etc.
  • the color sensitization rate with sensitizing dyes can be remarkably raised by incorporating these metal salts.
  • salts of trivalent or tetravalent metals such as an antimony, bismuth, arsenic, etc. may be incorporated therein.
  • the silver halide may be subjected to chemical sensitization such as reduction sensitization, gold sensitization, sulphur sensitization, etc.
  • desensitizing agents such as pinakryptol yellow, pinakryptol green, phenosafranine, etc. may be incorporated.
  • the silver halide emulsion thus prepared which has previously been provided with fog nuclei can further have incorporated, as is known, developing agents such as hydroquinones, 3-pyrazolidones, etc.
  • developing agents such as hydroquinones, 3-pyrazolidones, etc.
  • usual additives such as a coating assistant, a hardener, etc. or a color coupler may also be used in combination.
  • the dyes which are most characteristic of the invention are compounds having the foregoing general formula.
  • the groups in the formula are explained as follows.
  • L L and L each represents a methine group which may be substituted with an alkyl or aryl group.
  • Examples of alkyl groups represented by R or R are methyl, ethyl, propyl, isopropyl, butyl and hexyl group.
  • Examples of the substituted alkyl groups represented by R or R are Z-hydroxyethyl, 3-hydroxypropyl, 2-methoxyethyl, 3-carboxypropyl, 2-(2-carboxyethoxy)- ethyl, 2-sulfoethyl, 3-sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, 2-hydroxy-3-sulfopropyl, 2-(3-sulfopropoxy)ethyl, 2-acetoxy-3-sulfopropyl, 3 methoxy-2-(3-sulfopropoxy)- propyl, 2- ⁇ 2-(3-sulfopropoxy)ethoxy ⁇ ethyl, 2 hydroxy- 3 (3'-sulfopropoxy)propyl, benzyl, phenylethyl, p-sulfobenzyl, p-carboxybenzyl, p-sulfophenylethyl, and an
  • Examples of the alkyl groups represented by R or R are methyl, ethyl, propyl, isopropyl, butyl, etc.
  • EX- amples of the aralkyl groups represented by R or R are benzyl and phenylethyl group.
  • Examples of the anion represented by X are chlorine, bromine, iodine or the residues of thiocyanate, sulfonate, perchlorate, p-toluenesulfonate, methylsulfonate and ethylsulfate.
  • the benzene ring completed with Z may have substituents.
  • Examples of the oxazole ring completed with Z are residues of 4- methyloxazole, S-methyloxazole, 4-phenyloxazole, 4,5-diphenyloxazole, 4,5-dimethyloxazole, 4-ethyloxazole, t phenyloxazole, benzoxazole, 4-methylbenzoxazole, 5-meth ylbenzoxazole, 6 methylbenzoxazole, 7 methylbenzoxazole, S-chlorobenzoxazole, 6-chlorobenzoxazole, 5,6 dimethylbenzoxazole, 4,6 dimethylbenzoxazole, S-ethoxybenzoxazole, S-hydroxybenzoxazole, 6 hydroxybenzoxazole, alpha-naphthoxazole, beta-naphthoxazole, beta, betanaphthoxazole, etc.
  • the dyes used in the invention are conveniently dissolved in a solvent such as water, methanol, ethanol, methylCellosolve, etc., and added to an emulsion as a solution.
  • a solvent such as water, methanol, ethanol, methylCellosolve, etc.
  • the effective amount of the dyes to be added to silver halide emulsion is in the range of from 1 mg. to 100 mg., especially, from 1 mg. to 50 mg. per 1 kilogram of the emulsion.
  • the dyes are easily added to an emulsion immediately before coating, but they may also be added during the ripening after rinsing, or at the formation of precipitates before that.
  • the light-sensitive material is imagewise exposed.
  • the imagewise exposure is usually carried out by superposing the light-sensitive material on the original in such a way that the light-sensitive layer of the former is closely in contact with the latter, then irradiating the superposed assembly with light from the side of the original or the light-sensitive material.
  • the former is referred to as transmission printing, and the latter as reflective printing.
  • the light-sensitive material is developed and, if necessary, fixed, washed and dried.
  • the resulting copy itself may be used as a photograph, or may be used, as is described above, as an intermediate original for copying to a diazo light-sensitive material.
  • the light-sensitive material of the invention shows far more superior characteristics to that of the conventional light-sensitive material of this kind, especially when copying is conducted using an original of low contrast (not being limited to a blue original) and a mercury lamp which emits light of long wavelength as a light source.
  • an original of low contrast not being limited to a blue original
  • a mercury lamp which emits light of long wavelength as a light source.
  • the invention is extremely useful from the industrial standpoint.
  • EXAMPLE 1 An aqueous solution of sodium carbonate was added to 1 kg. of silver chlorobromoiodide emulsion (containing 33 g. of silver halide, which consisted of 2 mol percent of silver bromide, 2 mol percent of silver iodide and 96 mol percent of silver chloride) containing mg. of ammonium rhodium chloride [(NH RhCl at the time of forming the precipitates to adjust the pH to 8.5. Thereafter, 10 cc. of formalin (1% formaldehyde aqueous solution) was added thereto, and the mixture heated to 40 C. for 80 minutes to form fog nuclei. Then the pH was adjusted to 6.0 with citric acid and, thereafter, 10 mg.
  • silver chlorobromoiodide emulsion containing 33 g. of silver halide, which consisted of 2 mol percent of silver bromide, 2 mol percent of silver iodide and 96 mol percent of silver chloride
  • the peak of the light-sensitive material in the sensitized wavelength region was at a wavelength of about 545 m
  • the light-sensitive material obtained in this example was exposed imagewise using an original of blue diazo light-sensitive material with the use of diazo copying apparatus containing a fluorescent lamp as a light source in a room wherein a fluorescent lamp for general lighting was lit, the illuminance in the room being 50 lux.
  • a yellow filter for cutting light of wavelengths shorter than 500 m was used in order to increase contrast between the images and the background.
  • the printing sensitivity decreased compared with that of the dye of this invention, and hence the dye was required in an amount about 3 times as much as that of the dye of this invention in order to obtain the same printing sensitivity.
  • EXAMPLE 2 An aqueous solution of sodium carbonate was added to 1 kg. of silver bromoiodide emulsion (containing 43 g. of silver halide consisting of 2 mol percent of silver iodide and 98 mol percent of silver bromide) containing 40 mg. of potassium ruthenium chloride [K RuCl at the time of forming the precipitates to adjust the pH to 9.0. Thereafter, 3 cc. of 1% aqueous solution of hydrazine hydrochloride and 1 cc. of 0.01% aqueous solution of potassium chloroaurate were added thereto, and it was heated to 45 C. for minutes to form fog nuclei.
  • silver bromoiodide emulsion containing 43 g. of silver halide consisting of 2 mol percent of silver iodide and 98 mol percent of silver bromide
  • K RuCl potassium ruthenium chloride
  • the pH was adjusted to 5.5 with citric acid and, thereafter, 5 mg. of pinakryptol green and 5 mg. of the aforesaid dye 2 were added and the resultant solution coated on a polyethylene terephthalate photographic film so that the amount of silver halide coated was 3 g. per square meter of the film.
  • the peak of the light-sensitive material in the sensitized wavelength region was at the wavelength of about 540 m
  • the light-sensitive material obtained in this example was exposed imagewise using a blue diazo original with the use of a diazo copying apparatus containing a mercury lamp in a room wherein a fluorescent lamp for roomlighting was lit, the illuminance in the room being 50 lux.
  • the procedures of taking out the light-sensitive material from a sealed wrapper, exposing and developing it (a rapid processing apparatus which automatically conducts the development, fixing, washing and drying was employed) required seconds. During this period, the light-sensitive material was exposed to the room-lighting lamp for 40 seconds.
  • the light-sensitive material wherein 13 mg. of the dye represented by the following formula:
  • the printing sensitivity decreases compared with that of the dye of the invention, and hence the dye was required in an amount about 2.6 times as much as that of the dye of the invention in order to obtain the same printing sensitivity.
  • the light-sensitive material obtained in, this example was exposed imagewise using a blue diazo original with the use of a diazo copying apparatus containing a fluorescent lamp therein in a room wherein a fluorescent lamp for room-lighting was'lit," the 'illuminance in the room being lug.
  • procedures of taking out the lightsensitive material'from a sealed wrapper, exposing, developing and stabilizing it required 40 seconds.
  • the light-sensitive material wherein 13 mg. ,of. the dye in the Example 1 forcomparison was used and coated in the same way was processed in the same manner. But 1 in" this case, when the material was processed in a bright room the image density greatly decreased compared with when processed in a dark room.
  • the printing-sensitivity decreased compared with that ofthe dye of this invention, and hence the dye was required in. an amount about 4 times as muchasthat of the dye of this invention in order to obtainthesanie printing sensitivity.
  • a direct reversal silver halide photographic lightsensitive material used in the copying method in which the bright lines [of mercury, mainly'of-5460 A. and 5770 A. in wavelength, are utilized as a light source, wherein a silver halide emulsion layer, whose silver halide grains are uniformly fogged, provided onthe light-sensitive material has incorporated therein a compound containing a metal of groupVIII of the periodic table, said compound increasing the color.
  • sensitization of the emulsion by a sensitizing dye and a dye represented by the following formula wherein-L L and each represents-a methine group; R and R each represents an alkyl group or a sus'btituted alkyl group wherein said alkyl group or saidsubstituted alkyl group are of the type usually employed as a N-sub stituent inwcyaninedyes; R and R each represents an alkyl, aralkyl or allylgroup; X represents an anion; n represents aninteger of"1*"or' 2; Z represents a group of atoms necessary co, complete a benzene or naphthalene ring; and Z represents a group of non-metallic atoms necessary to complete an oxazole ring; wherein R and R 10 and R and L respectively, may be connected with each other through an alkylene chain.
  • said emulsion layer further contains a salt of a trivalent or tetravalent metal to further increase the color sensitization of the emulsion by said sensitizing dye.
  • substituted alkyl group is selected from the group consisting of Z-hydroxyethyl, 3-hydroxypropyl, 2-methoxyethyl, 3-carboxypropyl, 2-(2-carboxyethoxy)ethyl, 2-sulfoethyl, 3-sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, 2-hydroxy-3-sulfopropyl, 2-(3-sulfopropoxy)ethyl, -2-acetoxy- 3sulfopropyl, 3-methoxy-2-(3-sulfopropoxy)propyl, 2 ⁇ 2- (3-sulfopropoxy)ethoxy ⁇ ethyl, 2-hydroxy 3 (3 sulfopropoxy)propyl, benzyl, phenylethyl, p-sulfobenzyl, p-carboxylbenzyl, p-sulfophenyleth
  • said oxazole ring is selected from the group consisting of 4-methyloxazole, S-methyloxazole, 4-phenyloxazole, 4,5- diphenyloxazole, 4,5-dimethyloxazole, 4-ethyloxazole, tphenyloxazole, benzoxazole, 4-methylbenzoxazole, 5- methylbenzoxazo'le, 6-methylbenzoxazole, 7-methylbenzoxazole, S-chlorobenzoxazole, 6-chlorobenzoxazole, 5,6- dimethylbenzoxazole, 4,6-dimethylbenzoxazole, S-ethoxybenzoxazole, S-hydroxybenzoxazole, fi-hydrox ybenzoxazole, alpha-naphthoxazole, beta-naphthoxazole and betanaphthoxazole.
  • Thephotographic material of claim 1 wherein said dye is selected from the group consisting of 13 14 mo CH, 20.
  • said photographic material of claim 1 wherein said compound of said metal is an ammonium metal chloride /0 or a potassium metal chloride.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
US00213809A 1970-12-29 1971-12-29 Fogged,direct-positive silver halide emulsion layer containing a cyanine dye and a compound containing a metal of group viii of the periodic table Expired - Lifetime US3782957A (en)

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JP45121455A JPS526617B1 (enrdf_load_stackoverflow) 1970-12-29 1970-12-29

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US (1) US3782957A (enrdf_load_stackoverflow)
JP (1) JPS526617B1 (enrdf_load_stackoverflow)
CA (1) CA989238A (enrdf_load_stackoverflow)
DE (1) DE2164275A1 (enrdf_load_stackoverflow)
GB (1) GB1350230A (enrdf_load_stackoverflow)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3890154A (en) * 1969-12-24 1975-06-17 Fuji Photo Film Co Ltd Light-sensitive silver halide photographic materials
US3933498A (en) * 1973-09-28 1976-01-20 E. I. Du Pont De Nemours And Company Fogged, direct positive silver halide emulsions containing a bleach inhibiting compound and a Dmin maintainer compound
US3957518A (en) * 1972-07-13 1976-05-18 Agfa-Gevaert N.V. Direct-positive silver halide emulsions
US3970461A (en) * 1970-10-01 1976-07-20 Fuji Photo Film Co., Ltd. Fogged, direct-positive silver halide emulsion containing carbocyanine dye having indolenine nucleus
US4173483A (en) * 1975-05-27 1979-11-06 Konishiroku Photo Industry Co., Ltd. Silver halide photographic emulsions for use in flash exposure
US20080033179A1 (en) * 2004-07-29 2008-02-07 Adeka Corporation Optical Recording Material and Optical Recording Medium

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4688480B2 (ja) * 2004-11-25 2011-05-25 株式会社Adeka シアニン化合物、該化合物を用いた光学記録材料、及び光学記録媒体

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3890154A (en) * 1969-12-24 1975-06-17 Fuji Photo Film Co Ltd Light-sensitive silver halide photographic materials
US3970461A (en) * 1970-10-01 1976-07-20 Fuji Photo Film Co., Ltd. Fogged, direct-positive silver halide emulsion containing carbocyanine dye having indolenine nucleus
US3957518A (en) * 1972-07-13 1976-05-18 Agfa-Gevaert N.V. Direct-positive silver halide emulsions
US3933498A (en) * 1973-09-28 1976-01-20 E. I. Du Pont De Nemours And Company Fogged, direct positive silver halide emulsions containing a bleach inhibiting compound and a Dmin maintainer compound
US4173483A (en) * 1975-05-27 1979-11-06 Konishiroku Photo Industry Co., Ltd. Silver halide photographic emulsions for use in flash exposure
US20080033179A1 (en) * 2004-07-29 2008-02-07 Adeka Corporation Optical Recording Material and Optical Recording Medium
EP1772282A4 (en) * 2004-07-29 2009-08-12 Adeka Corp OPTICAL RECORDING MATERIAL AND OPTICAL RECORDING MEDIUM
US7674569B2 (en) 2004-07-29 2010-03-09 Adeka Corporation Optical recording material and optical recording medium
US20100080947A1 (en) * 2004-07-29 2010-04-01 Adeka Corporation Optical recording medium

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DE2164275A1 (de) 1972-07-13
GB1350230A (en) 1974-04-18
CA989238A (en) 1976-05-18
JPS526617B1 (enrdf_load_stackoverflow) 1977-02-23

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