Fuji Photo Film Company, Limited

Tadao Sugimoto

Hideo Ikeda

Masaki Okazaki

Shigeo Hirano

Koki Nakamura

Sumito Yamada

Yoshihiro Takagi

Tsutomu Miyasaka

Tadashi Ikeda

Hiroyuki Mifune

Ichizo Toya

Shinji Sakaguchi

Shigeharu Urabe

Toshiaki Hayakawa

Haruo Takei

Nobuo Tsuji

Masakazu Yoneyama

Akihiko Ikegawa

Takushi Miyazako

Kiyoteru Miyake

Tadaaki Tani

Nobuyuki Tsujino

Kenji Yokoo

Satosi Kubota

A photoelectric conversion device having a photosensitive layer comprising semiconductor particles is disclosed, in which the semiconductor particles are obtained from a metal hydroxide gel or a precursor thereof present in a hydrophilic solvent. Also disclosed in a photoelectric cell including the photoelectric conversion device.

Photoelectric conversion device and photoelectric cell

A silver halide photographic material comprising a support having thereon at least one silver halide emulsion layer spectrally sensitized by at least one adsorptive spectral sensitizing dye, wherein the emulsion layer or a hydrophilic colloid layer adjacent to the emulsion layer contains at least one compound represented by following formula (I), (II), or (III); ##STR1##

Silver halide photographic materials

A silver halide photographic material comprising a support having thereon at least one silver halide emulsion layer containing at least 1.0.times.10.sup.-4 gram equivalent of an anionic surface active material as anion per gram of a hydrophilic dispersion medium in the emulsion layer, the material having dispersed in the emulsion layer a light-collecting dye that has an emission band overlapping at least partially with the optical absorption band of a spectral sensitizing dye on a silver halide grain present in the emulsion layer, the light-collecting dye having an emission quantum yield of at least 0.1 at a concentration of 10.sup.-4 mol/dm.sup.3 in dry gelatin at room temperature, with the proviso that the light-collecting dye and the spectral sensitizing dye may be the same compound.

Silver halide photographic material

A silver halide photographic material is disclosed containing at least one silver halide emulsion layer, in which (1) the silver halide grains constituting the emulsion layer have been spectrally sensitized by at least one adsorbable spectral sensitizing dye added thereto before the completion of chemical ripening of the grains, and (2) at least one luminous dye which has a quantum efficiency of 0.1 or more when the concentration thereof in dry gelatin at room temperature is 10.sup.-4 mol/dm.sup.3 and which can be substantially completely removed by development is added to a hydrophilic dispersion medium for the emulsion layer exclusive of the silver halide grains in a concentration of 2.0 mmol/dm.sup.3 in the dispersion medium. The addition of the spectral sensitizing dye is not limitative and can be either before the completion of the formation of the silver halide grains or during a stage from the completion of the formation of the grains to the completion of the chemical ripening thereof. By the combination of the spectral sensitization by the adsorbable spectral sensitizing dye and light-collecting sensitization by the luminous dye, the spectral sensitivity of the silver halide in the material is unexpectedly improved.

Silver halide photographic materials spectrally sensitized with luminous

A silver halide photosensitive material comprising a support having thereon at least one silver halide emulsion layer comprising tabular grains whose diameter of an average projected area/average thickness ratio is 5/1 or higher is provided. Said emulsion layer contains one or more luminescent dyes whose luminescence quantum yield is 0.3 or more when its concentration is dry gelatin is 10.sup.-4 mol/dm.sup.3 at room temperature and that can be substantially removed by development processing, and the content of said luminescent dye is 3.0 .mu.mol/m.sup.2 or more for the total surface area of the silver halide grains in said emulsion layer, or is 2.0 mmol/dm.sup.3 or more in a hydrophilic dispersion medium excluding the silver halide grain surfaces in said emulsion layer.

Tubular silver halide photosensitive materials sensitized with a

A silver halide photographic material having at least one silver halide emulsion layer having been spectrally sensitized with adsorbable spectral sensitizing dye is disclosed, wherein a hydrophilic dispersion medium contains a substantially non-adsorbable luminescent dye which is easily removable by development processing the satisfies the following conditions (1) to (3):

A method for preparing a light-sensitive silver iodobromide emulsion having a high aspect ratio, the emulsion containing a dispersion medium and silver iodobromide grains, with grains having a grain size of not less than 0.5 .mu.m, a thickness of not more than 0.3 .mu.m, and an average aspect ratio of not less than 5 constituting at least 50% of the total project area of emulsion grains, comprising (a) introducing a silver salt, and a bromide salt or a bromide salt and iodide salt into a reactor in which at least part of the dispersion medium has been introduced, (b) controlling the iodide ion concentration indicated by pI in the reactor prior to the introduction of at least the silver salt and the bromide salt within the range represented by the equation (I) as shown below: ##EQU1## wherein pI and pBr indicate the logarithmic values of reciprocals of concentrations of dissolved iodide ions and bromide ion, respectively, and (c) maintaining the pBr at not less than 0.8 after the introduction of the silver salt, and bromide salt or the bromide salt and iodide salt.

Method for preparing silver iodobromide emulsions having high aspect

A silver halide photographic emulsion and a method for production thereof are described, said emulsion comprising silver halide grains which are comprised of silver iodobromide and have a multilayer structure formed from a core and at least one covering layer and an aspect ratio below 5, said silver halide grains being chemically sensitized and having a halogen composition such that the difference in average iodide content beween adjacent layers, each of which has a substantially homogeneous iodide distribution, is not less than 10 mol %, and the iodide content in the outermost layer is not more than 40 mol %.

Core/shell silver halide photographic emulsion and method for production

A silver halide photographic light-sensitive material is disclosed. The material is comprised of a support having thereon a silver halide emulsion layer containing light-sensitive silver halide grains, at least 10% (in number) of said halide grains being tabular grains having a diameter/thickness ratio of not less than 5. The tabular grains include an iodine-containing silver halide solid solution in an interior portion thereof which is contained in areas covering, with regard to its major or minor axis direction, 80% by mole of the silver contained in the grain. Further, the tabular grains have an average iodine content in the internal high iodine phase which is five times that of the silver bromide, iodobromide or chloroiodobromide contained in the phase present outside of the internal high iodide phase. In addition, the silver contained in the internal high iodine phase is not more than 50% by mole of the total amount of silver in the tabular grains. The photographic material has the advantages inherent to the use of tabular grains and has improved pressure resistant characteristics.

Silver halide photographic light-sensitive material

A silver halide photographic light-sensitive material is disclosed. The material is comprised of a support having provided thereon at least one silver halide emulsion layer which is coated with a surface protective layer. The silver halide emulsion layer includes an inside fogged silver halide emulsion and a light-sensitive silver halide emulsion containing silver halide grains which are tabular silver halide grains having a grain diameter which is 5 times or more the grain thickness. The material is highly sensitive and forms images which have high contrast and a high maximum density. The material can be developed in a relatively short developing time at a low temperature treatment without using additives.

Silver halide photographic light-sensitive materials

A silver halide emulsion containing negative working silver halide grains each comprising a core of silver bromide or silver bromoiodide, a first coating layer exterior the core of silver iodide or silver bromoiodide, and a second coating layer exterior the first coating layer composed of silver bromide or silver bromoiodide different from that of the first coating layer in halide composition, and having a projected area diameter-to-thickness ratio of less than 5, in which: (1) the first coating layer contains more iodide than the core by 10 mol % or more; and (2) silver in the first coating layer accounts for 0.01 to 30 mol % of the total silver in the grain.

Silver halide emulsion

A silver halide photographic light-sensitive material is disclosed. The material is comprised of a support base having provided thereon a hydrophilic colloid layer and a silver halide emulsion layer. The silver halide emulsion layer contains tubular silver halide grains having a diameter at least 3 times their thickness and also contains a compound represented by general formula (I) or (II): ##STR1## the substituents are defined within the specification. The material obtains the advantages of utilizing tabular silver halide grains while having a reduced dependents of its photographic properties on development processing conditions which normally effect materials containing tabular silver halide grains.

A method of developing silver halide photographic material which contains a light-sensitive silver halide emulsion and an internally-fogged silver halide emulsion, in which the internally-fogged emulsion has internal fogging nuclei at a depth of 0.02.mu. or more below the surface of the grains is disclosed. The photographic material is developed in the presence of at least one compound selected from the group consisting of tetraazaindenes containing at least one mercapto group, purines containing at least one mercapto group, triazaindenes containing at least one mercapto group and pentaazaindenes containing at least one mercapto group, to increase photographic speed, contrast and maximum density as well as remove uneven stain.

Method of developing silver halide photographic light-sensitive material

A silver halide photographic light-sensitve material is disclosed. The material is comprised of a transparent support having provided on one side of the support at least two silver halide emulsion layers and a surface-protecting layer. One of the two silver halide emulsion layers is a tabular silver halide emulsion layer containing tabular silver halide grains having a diameter at least five times the thickness of the grains. The other silver halide emulsion layer is a non-tabular silver halide emulsion layer containing non-tabular silver halide grains. The tabular silver halide emulsion layer is positioned closer to the support than the non-tabular silver halide emulsion layer, and the non-tabular silver halide emuslion layer is positioned closer to the support than the surface-protecting layer. The material may include two similar silver halide emulsion layers and a surface-protecting layer on the opposite side of the support. The material provides images with improved sharpness without a decrease in sensitivity while effectively utilizing the amount of silver.

A previously unfogged internal latent image-type direct positive silver halide emulsion and a photographic material incorporating such emulsion are described, wherein the emulsion contains at least one sensitizing dye represented by formula (I): ##STR1## wherein one of R.sup.1 and R.sup.2 represents a sulfoalkyl group and the other thereof represents an unsubstituted or substituted alkyl group, an unsubstituted or substituted aryl group, or a pyridyl group; X represents a sulfur atom or an oxygen atom; Y represents a sulfur atom, an oxygen atom, or ##STR2## wherein R represents a lower alkyl group or --CH.sub.2).sub.n.sbsb.1 O--CH.sub.2).sub.n.sbsb.2 OH, wherein n.sub.1 and n.sub.2 each represents an integer of 1 to 4; and W represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, or an unsubstituted or substituted phenyl group.

Growing community of inventors

Kanagawa, Japan

Tadao Sugimoto