Abstract: A silver halide photographic emulsion prepared in the presence of at least one member of polymers comprising at least one repeating unit derived from at least one member of monomers represented by the following formula (1) ##STR1## wherein R.sup.1 represents a hydrogen atom or a lower alkyl group; R.sup.2 represents a monovalent substituent group; R.sup.3 represents an alkylene group having 3 to 10 carbon atoms; L represents a bivalent bonding group; and n represents the mean number of a repeating unit represented by --R.sup.3 --O-- and is a number of at least 4, but not more than 200.

Abstract: A color diffusion transfer light-sensitive material is described including a support having thereon at least one light-sensitive emulsion layer associated with a dye image-forming material and an electron donor, wherein the dye image-forming material comprises at least one reducible dye-providing compound represented by formula (I) which releases a diffusible dye upon being reduced and tabular silver halide grains having a mean grain diameter of at least about 0.3 .mu.m, a mean grain thickness of less than about 0.5 .mu.m, and a mean aspect ratio of at least about 2 account for at least about 50% of the total projected area of the silver halide grains contained in at least one light-sensitive emulsion layer;PWR - (Time).sub.t - Dye (I)wherein PWR represents a group capable of releasing -(Time).sub.t -Dye upon being reduced; Time represents a group capable of releasing Dye through a subsequent reaction after being released as -(Time).sub.

Abstract: Disclosed is a novel process for the preparation of tabular silver halide grains having parallel twinning planes which comprises the steps of:1) supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of a water-soluble halide and an aqueous solution of a protective colloid into a mixing machine provided external to a reaction vessel where they are mixed to form nuclear grains; and2) introducing the nuclear grains into a ripening vessel comprising a pipe where they are ripened at an elevated temperature.

Abstract: A process and apparatus for producing silver halide grains wherein by removing water, etc., from a liquid containing fine, silver halide grains formed in a mixer and being added to a reaction vessel, the yield of the silver halide grains grown in the reaction vessel per unit amount of the raw materials used is increased. Also, by removing a portion of the water, used for the dilution, from the liquid being added to the reaction before the addition thereof, the amount of diluting water effective for the formation of silver halide fine grains in the mixer is increased, to thereby form finer silver halide grains in the mixer.

Abstract: A method of preparing a superfine grain emulsion with a grain size of 0.05 .mu.m or less is provided, which includes mixing aqueous solutions of a water-soluble silver salt and a water-soluble halide with vigorous stirring inside a closed mixing device furnished with an agitator, where the solutions are fed into the device simultaneously and continuously, in the presence of at least one of a high molecular compound and a substance capable of adsorbing to silver halide, each of which has a physical retardance value of at least 40 as determined by PAGI method, and immediately expelling the newly-formed grains from the mixing device. Another method includes mixing the aqueous solutions in a mixing device as described above, immediately expelling the newly-formed grains from the device, and mixing the expelled grains with at least one of the above-described high molecular compound and substance.

Abstract: A silver halide photographic emulsion containing tabular silver halide grains which have an aspect ratio of 2 or more and in which dislocations are localized in a center portion of each grain. The tabular silver halide grains have a thickness of less than 0.5 .mu.m and a diameter of 0.3 .mu.m or more and account for at least 50% of a total projected area of the silver halide grains. This emulsion has a high sensitivity and good reciprocity characteristics. In a photographic light-sensitive material having at least two light-sensitive silver halide emulsion layers having different color sensitivities on a support, the above tabular silver halide photographic emulsion and at least one type of a coupler which is coupled with an oxidant of a color developing agent to develop a color are added to at least one of the emulsion layers, thereby obtaining a photographic light-sensitive material having a high sensitivity and good reciprocity characteristics.

Abstract: An apparatus for forming silver halide grains comprises a reaction vessel for causing the nucleus formation and the crystal growth of silver halide grains. The apparatus further includes: a mixer disposed outside of the reaction vessel and having a high-speed stirring blade; conduits for supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of water-soluble halide, and an aqueous protective colloid solution to the mixer while controlling the rotational speed of the high-speed stirring blade to form fine, silver halide grains; and a conduit for connecting the mixer to the reaction vessel for immediately supplying the fine grains in the mixer to the reaction vessel.

Abstract: A method of preparing a superfine grain emulsion with a grain size of 0.05 .mu.m or less is provided, which includes mixing aqueous solutions of a water-soluble silver salt and a water-soluble halide with vigorous stirring inside a closed mixing device furnished with an agitator, where the solutions are fed into the device simultaneously and continuously, in the presence of at least one of a high molecular compound and a substance capable of adsorbing to silver halide, each of which has a physical retardance value of at least 40 as determined by PAGI method, and immediately expelling the newly-formed grains from the mixing device. Another method includes mixing the aqueous solutions in a mixing device as described above, immediately expelling the newly-formed grains from the device, and mixing the expelled grains with at least one of the above-described high molecular compound and substance.

Abstract: A silver halide photographic material, which comprises a support having thereon at least one silver halide emulsion layer, the silver halide emulsion layer containing light-sensitive silver halide grains having a structure such that cores of the respective grains have a completely uniform halide distribution and that shells with a higher silver chloride content than the cores are deposited outside the cores with no projections.

Abstract: A process of producing silver halide grains by disposing a mixer outside of a reaction vessel for causing a nucleus formation and/or a crystal growth of silver halide grains and containing an aqueous protective colloid solution. The process further includes the steps of: supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of a water-soluble halide(s), and an aqueous solution of a protective colloid to the mixer while controlling the flow rates of the solutions; mixing them while controlling the rotational speed of a stirring blade of the mixer to form fine, silver halide grains; and immediately supplying the fine grains into the reaction vessel to perform the nucleus formation and/or the crystal growth of the silver halide grains in the reaction vessel. The silver halide fine grains thus formed in the mixer are quickly diluted with a liquid withdrawn from the reaction vessel and then the diluted mixture is supplied to the reaction vessel.

Abstract: Disclosed is a silver halide color photographic material comprising at least one silver halide emulsion layer on a support. The silver halide emulsion contains silver chlorobromide grains having a 2 to 4 layer stacked structure which layers differ in their content of silver chloride. The silver chloride distribution of each layer of the grains is completely uniform, and the difference in the silver chloride content between a first layer and a second layer of said grains ranges from 5 mole % to 27 mol %.

Abstract: A process of forming silver halide grains which comprises disposing a mixer outside of a reaction vessel for causing the nucleus formation and crystal growth of silver halide grains. The process further includes the steps of: supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of a water-soluble halide, and an aqueous protective colloid solution into the mixer to form fine, silver halide grains therein; immediately supplying the fine grains into the reaction vessel; and performing the nucleus formation and crystal growth of the silver halide grains in the reaction vessel. The formation of the fine grains is controlled by controlling the flow rates of the solutions being supplied to the mixer and the r.p.m. of a stirrer provided in the mixer.

Abstract: A silver halide photographic emulsion comprising a dispersant and silver halide grains, at least 50% of the total projected area of the silver halide grains being occupied by tabular grains having an average aspect ratio of 2 or more, the tabular grains comprising opposing parallel major faces consisting of a (1 1 1) face, and at least 30% of the tabular grains having an indentation or space in the central portion of the major faces thereof.

Abstract: A control process and apparatus for the formation of silver halide grains comprising a mixer disposed outside of a reaction vessel containing an aqueous protective colloid solution and causing a nucleus formation (nucleation) and/or a crystal growth of silver halide grains. The process and apparatus further include: supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of water-soluble halide(s), and an aqueous solution of a protective colloid to the mixer through supply conduits while controlling the flow rates of the solutions; mixing them while controlling the rotational speed of a stirrer of the mixer to form fine, silver halide grains; and immediately supplying the fine grains into the reaction vessel through a conduit connecting the mixer to the reaction vessel to perform the nucleus formation and/or the crystal growth of the silver halide grains in the reaction vessel.

Abstract: A silver halide photographic material is disclosed which comprises at least one silver halide emulsion layer on a support, wherein light-sensitive silver halide grains in the silver halide emulsion layer or layers are obtained by charging previously prepared silver halide particles having a fine size into a reaction vessel which allows nucleation and/or crystallization of the light-sensitive silver halide grains so that nucleation and/or crystallization are effected in the reaction vessel, and the light-sensitive silver halide grains are subjected to chemical ripening in the presence of a silver halide solvent. A process for the preparation of the silver halide photographic material is also disclosed.

Abstract: A process for manufacturing uniform silver halide grains, which comprises the steps of:(A) providing a mixer vessel and a reactor vessel, the mixer vessel being separate from the reactor vessel and the reactor vessel having contained therein an aqueous protective colloid solution and in which silver halide grains are grown;(B) feeding an aqueous water-soluble silver salt solution, an aqueous water-soluble halide solution and an aqueous protective colloid solution into the mixer vessel;(C) forming a fine silver halide grain-containing solution by mixing the thus fed solutions in the mixer vessel;(D) immediately feeding the thus formed fine silver halide grain-containing solution into the reactor vessel; and(E) stirring said solution in the reactor vessel to grow uniform silver halide grains therein.

Abstract: A silver halide emulsion comprises a dispersion medium and silver halide grains, the silver halide emulsion containing tabular silver halide grains having a thickness of less than 0.5 .mu.m, a diameter of 0.3 .mu.m or more, and a mean diameter-to-thickness ratio of 2 or more. The tabular grains occupy at least 50% of a projected area of all the silver halide grains, and 50% or more (number) of the tabular grains include 10 or more dislocations per grain. A photographic light-sensitive material comprises the aforementioned silver halide emulsion.

Abstract: A silver halide emulsion is described comprising a dispersion medium and silver halide grains, wherein the projected area of hexagonal tabular silver halide grains having as the outer surfaces two parallel hexagonal planes having a ratio of the longest edge length to the shortest edge length (referred to as the adjacent edge ratio) of 2/1 or less accounts for at least 70% of the projected area of the whole silver halide grains, and further the hexagonal tabular silver halide grains are monodisperse grains. The process of production of the silver halide emulsions is also described.

Abstract: A process for producing a tabular silver halide emulsion by using a sulfur-containing silver halide solvent that promotes growth of silver halide grains, and a light-sensitive material containing the emulsion are disclosed. The grain growth effect of the silver halide solvent is reduced or eliminated by using an oxidizing agent thereby excluding the adverse effect of the silver halide solvent upon chemical ripening.

Abstract: An internal latent image silver halide emulsion is disclosed comprising core/shell silver halide particles having a chemically sensitized surface which are composed of a core of silver halide doped with metal ions and/or subjected to chemical sensitization and a shell which covers said core as far as to do at least the sensitive sites of said core and a binder, wherein said silver halide emulsions contain a polymer containing a repeating unit represented by the following general formula (I) in an amount of 2 mg to 1000 mg per mole of silver as the weight of said repeating units in said polymer: ##STR1## wherein R.sup.1 represents a hydrogen atom or an alkyl group and Q represents a group selected from the group consisting of the following (1)-(4): ##STR2## wherein q represents an integer of 2 to 4, ##STR3## wherein R.sup.2 and R.sup.3 each represents a hydrogen atom or an alkyl group, ##STR4## wherein Z.sup.