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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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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light
silver halide
emulsion layer
dye
sensitive material
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US00213809A
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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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    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03CPHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00Photosensitive materials
    • G03C1/005Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/485Direct positive emulsions
    • G03C1/48515Direct positive emulsions prefogged
    • G03C1/48523Direct positive emulsions prefogged characterised by the desensitiser
    • G03C1/4853Direct 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.

Abstract

A DIRECT REVERSAL SILVER HALIDE PHOTOGRAPHIC MATERIAL SUITABLE FOR USE IN A COPYING PROCESS ULITIZING A MERCURY OR FLUORENSANT 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 ILUMINATION, AND THE RESULTANT PHOTOGRAPHIC MATERIAL CAN BE HANDLED UNDER INDOOR ILLUMINATION WITHOUT CAUSING THE BREAKAGE OF THE FOG NUCLEI, AND GIVE IMAGES OF GOOD CONTRAST.

Description

UnitedStates Patent US. Cl. 96-401 20 Claims ABSTRACT OF THE DISCLOSURE 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.
As has heretofore been publicly known, in light-sensitive materials of this kind silver halide contained in the emulsion layer thereof is provided with fog nuclei by exposure to light or by a chemical process, and when copying on this light-sensitive material is conducted, positive images can be formed by one imagewise exposure (i.e., to expose the emulsion layer imagewise to light) and one development processing.
In the above described light-sensitive material, positive images can directly be obtained, while in the general lightsensitive materials wherein silver halide is not provided with the fog nuclei, negative images are formed by one imagewise exposure and development processing. Therefore, 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. In the copying of this type, 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.
It has heretofore been known that in light-sensitive material formed of a silver halide emulsion which contains a compound of a Group VIII metal in the Periodic Table, such as a rhodium salt, high in inner sensitivity and previously provided with fog nuclei, 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. However, 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. In addition, no special treatment has been conducted as to the peak of the spectral sensitivity in the case of such light-sensitive materials.
On the other hand, from the standpoint of the ease of the copying procedure, a light-sensitive material is preferred that can be dealt with in a bright place.
As is obvious from the reasons described above, it is preferable that 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).
Heretofore, in the case of copying a blue-image original, a copying apparatus equipped with a mercury lamp as a light source has been used, cutting the light of wavelengths shorter than about 5000 A. by a yellow filter. However, in such procedure, the light-sensitive material cannot be protected from a room-lighting lamp.
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.,
low in sensitivity to light of wavelengths 3660 A., 4047 A. and 4358 A. among the wavelengths at which the spectral distribution of the bright lines of mercury emitted from the above described fluorescent lamp is maximum. According to the invention, the above object can be achieved by 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 be connected with each other through an alkylene chain.
The invention will be described in detail below.
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. As the silver halide to be contained in the emulsion, 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.
These 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. In order to raise the sensitivity further, salts of trivalent or tetravalent metals such as an antimony, bismuth, arsenic, etc. may be incorporated therein. In addition, the silver halide may be subjected to chemical sensitization such as reduction sensitization, gold sensitization, sulphur sensitization, etc. Furthermore, in order to prevent the forming of negative images in excess by exposed region, 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. In addition, 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 the methine group are -CI-I=, C(CH C(C H and -C(C H 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 allyl group. 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.
When at least one of the dyes represented by the above described general formula is added to a light-sensitive material containing the compounds of the Group VIII metal of the periodic table, and having been previously provided with fog nuclei, the sensitivity thereof to light of long wavelength, mainly to light of 5461 A. and/or 5770 A. in wavelength, is remarkably increased and, in addition, the sensitivity to light of short wavelength, mainly to light of 3660 A., 4047 A. and 4358 A. in wavelength, is effectively reduced. Accordingly, a direct reversal silver halide photographic light-sensitive material whose fog nuclei have resistance to breakage even when handled under a light source of a room-lighting fluorescent lamp can be obtained.
Examples of the dyes of the foregoing general formula which bring about especially good results in the invention are as follows.
Dye 1 Ha CH3 CH=CHCH= OH;
I CH3 C2Hs Br- Dye 2 HaC CHa C rncon.
CH=CH-CH= CH;
N i 41H CzHg I Dye 3 H30 CH:
CH=CHCH= I CH; C3115 Bl I Dye 14 bye 13 Dye 16 1 Dye 19 Dye'20 CH; C
CHI-- 0 H=CHa These dyes used for the invention can readily be synthesized by'reference to thedescriptionin The Cyanine Dyes and the Related Compounds written by M.
Hamer, published by Interscience Publishers Co. in 1964, at pages 62-199.
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. 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.
An example of the embodiment of the copying method using the light-sensitive material in the invention described above is explained as follows.
First, 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. After the exposure, 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. In addition, since the copying art is utilized in every field, the invention is extremely useful from the industrial standpoint.
The present invention will be illustrated in detail with the following examples.
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. of pinakryptol yellow and 4 mg. of the aforesaid dye 6 were added and coated on a photographic paper so that the amount of silver halide coated was 1.6 g; per square meter of the paper. 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. At the time of exposure, 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 procedures of taking out the light-sensitive material from a sealed wrapper, exposing, developing and stabilizing required 40 seconds. However, there was observed no diiference in photographic property compared with that wherein these procedures were conducted in a dark room. That is, it was possible to handle the lightsensitive material in a bright room under a fluorescent lamp quite safely. For comparison, the light-sensitive ma- O\ am was used instead of the above described sensitizing dye 6 and coated in the same manner was processed in the same way. But 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. In addition, since the peak in the sensitizing wavelength region is at about 510 III/1., 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. Then, 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. However, there was observed no difference in photographic property compared with that wherein these procedures were conducted in a dark room. That is, it was possible to handle the light-sensitive material quite safely in a bright room under a fluorescent lamp. For comparison, the light-sensitive material wherein 13 mg. of the dye represented by the following formula:
was used instead of the above described sensitizing dye and coated in the same manner was processed in the same way. But 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.
In addition, since the peak in the sensitized wavelength region is at about 510 my, 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.
9 EXAMPLES An aqueous solution of sodium carbonate was added to 1 kg. offsilver chlorobromoiodide"emulsion(containing g. of silver halide consisting erg mol percent of silver iodide, 20 mol pergent of silver bromide and 78 mol percent of silver chloride) containing 1Q mg. of potassium iridiumchloride.i[K IrCl at the time of forming the precipitates to adjust the pH to 8.5. Thereafter, 10 cc. of formalin (1%{ormaldehyde aqueous solution) was added thereto, and it was heated to C. for 85 minutes to form fog nuclei. Then the pH was adjusted to 5.5 with citric acid and, thereafter, 1Q mg. of pinakryptol yellow and 3 mg. of the aforesaid sensitizing dye 18 were added and coated on a photographic paper so that the amount of silver halidecoatedfwas 1.9 g. per lgsquare meter of the paper. The peak of the resulting lightesen'sitive material in the sensitized wavelength region was at about 552 mu.
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. However, there was observed no difference in photographic property compared with that wherein these procedures were conducted in a dark room. That is,it was possible to handle the light-sensitive material quite safety in a bright room under afluores'cent lamp.
For comparison, 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.
In addition, since the peak in the sensitize'd'wavelength region is at about 510mb, 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.
What is claimedisf 1. 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.
2. Thephotographic material of claim 1, wherein the amount of said dye is 1 to mg. per kilogram of said emulsion layer.
3. The photographic material of claim 1, wherein the amount of said dye is 1 to 50 mg. per kilogram of said emulsion layer.
4. The photographic material of claim 1, wherein 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.
5. The photographic material of claim 1, wherein said emulsion layer further contains a desensitizer.
6. The photographic material of claim 1, wherein said emulsion layer is chemically sensitized.
7. The photographic material of claim 1 wherein the mean grain size of said silver halide grains is less than 0.6 micron.
8. The photographic material of claim 1 wherein said metal is rhodium, ruthenium, iridium or osmium.
9. The photographic material of claim 4 wherein said trivalent or tetravalent metal is antimony, bismuth or arsenic.
10. The photographic material of claim 1 wherein said methine group is substituted with an alkyl or an aryl group. g
11. The photographic material of claim 10 wherein said substituent is methyl, ethyl or phenyl.
12. The photographic material of claim 1 wherein the alkyl of said R and R has from 1 to 6 carbon atoms.
13. The photographic material of claim 12 wherein the substituent of said substituted alkyl group is hydroxy, alkoxy, carboxy, sulfo, acetoxy, aryl or vinyl.
14. The photographic material of claim 13 wherein said 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-sulfophenylethyl, and allyl groups.
15. The photographic material of claim 1 wherein the alkyl of said R and R has from 1 to 4 carbon atoms.
16. The photographic material of claim 15 wherein said 1aralkyl group of said R and R is benzyl or phenylet y 17. The photographic material of claim 1 wherein said anion is chlorine, bromine, iodine, 'thiocyanate, sulfonate, perchlorate, p-toluenesulfonate, methylsulfonate or ethylsulfate.
18. The photographic material of claim 1 wherein 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.
19. Thephotographic material of claim 1 wherein said dye is selected from the group consisting of 13 14 mo CH, 20. The photographic material of claim 1 wherein said compound of said metal is an ammonium metal chloride /0 or a potassium metal chloride.
}"CH=CH*CH= C104 5 References Cited 13 UNITED STATES PATENTS I 1 2,717,833 9/1955 Wark 96--108 d CHCHCOOH 1 3,531,288 9/1970 Jones 96-408 m 3,567,456 3/1971 Riester et a1 96-134X H3O CH; 10
\ o NORMAN G. TORCHIN, Primary Examiner W. H. LOUIE, JR., Assistant Examiner /-GH=CH-CH= I 15 US. Cl. X.R. N f 96-107, 108, 125, 137
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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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
EP1772282A1 (en) * 2004-07-29 2007-04-11 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 (en) * 2004-11-25 2011-05-25 株式会社Adeka Cyanine compound, optical recording material using the compound, and optical recording medium

Cited By (10)

* 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
EP1772282A1 (en) * 2004-07-29 2007-04-11 Adeka Corporation Optical recording material and optical recording medium
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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