Method for manufacturing a silver halide emulsion

Claim 1

A method for manufacturing a silver halide emulsion comprising the steps of: forming a silver halide grain, spectral sensitizing by adding a spectral sensitizing dye and chemical maturing in this order wherein the spectral sensitizing is carried at a temperature not lower than 25°C and not higher than 55°C; and the chemical maturing is carried out at a temperature higher than the temperature of the spectral sensitizing.

Claim 7

The method of claims 2 or 3 to 6, wherein R₃ to R₆ each represent a hydrogen atom, an alkyl group having not more than 4 carbon atoms, aralkyl group, aryl group or a heterocyclic group represented by formula B: wherein Q represents a group of nonmetallic atoms necessary to form a five- or six-membered heterocyclic nucleus selected from the group consisting of pyrazolone derivatives, isooxazolone derivatives, oxazolone derivatives, 2,4,6-triketohexahydropyrimidine derivatives, 2-thio-2,4,6-triketohexahydropyrimidine derivatives, rhodanine derivatives, 2,4-thiazolidinedione derivatives, 2-thio-2,4-oxazolidinedione derivatives, thianaphthenone derivatives, hydantoin derivatives, indanedione derivatives and oxyindole derivatives.

Claim 8

The method of claims 2 or 3 to 7, wherein an average grain size of the silver halide grains is 0.2 to 1.6 µm.

Claim 10

The method of claims 2 or 3 to 9, wherein the silver halide grain contains not less than 90 mol % of silver chloride, not more than 10 mol % of silver bromide and not more than 0.5 mol % of silver iodide.

Claim 13

A method for manufacturing a silver halide photo-sensitive material comprising the steps of: (a) preparing a silver halide emulsion containing a silver halide grain having an average grain size of 0.25 to 1.2 µm, (b) spectral sensitizing by adding a spectral sensitizing dye, (c) chemical maturing, (d) forming a silver halide photo-sensitive layer on a support, wherein process is carried in this order; the spectral sensitizing is carried by adding a sensitizing dye represented by formula A, at a temperature 25° C to 55° C, wherein Z₁ and Z₂, being same or different, each represent a benzothiazole nucleus, a benzimidazole nucleus or benzothiazole nucleus, which may have a substituent; R₁ and R₂ each represent an alkyl group having a sulfo group; R₃ to R₆ each represent a hydrogen atom, an alkyl group having not more than 4 carbon atoms, aralkyl group, aryl group or a heterocyclic group represented by formula B: wherein Q represents a group of nonmetallic atoms necessary to form a five- or six-membered heterocyclic nucleus selected from the group consisting of pyrazolone derivatives, isooxazolone derivatives, oxazolone derivatives, 2,4,6-triketohexahydropyrimidine derivatives, 2-thio-2,4,6-triketohexahydropyrimidine derivatives, rhodanine derivatives, 2,4-thiazolidinedione derivatives, 2-thio-2,4-oxazolidinedione derivatives, thianaphthenone derivatives, hydantoin derivatives, indanedione derivatives and oxyindole derivatives. R₃ to R₆ each represent a hydrogen atom, an alkyl group having 4 or less carbon atoms, an aryl group, an aralkyl group, or a heterocyclic group; R₂ and R₆ when q = 2, or R₃ and R₅ when m = 2 and q =2, may form a five- or six-membered alkylene bridge; l, m, n, q and p each represent 1 or 2; X⁻ represents an anion; the chemical maturing is carried out at a temperature higher than the temperature applied at the spectral sensitizing; the silver halide grain contains not less than 90 mol % of silver chloride, not more than 10 mol % of silver bromide and not more than 0.5 mol % of silver iodide; and the emulsion contains not less than 60 weight % of grains having not less than 90 mol % of silver chloride content.