Amphoteric maleic anhydride copolymers and photographic emulsions employing the same

Claim 1

A photographic silver halide emulsion, wherein the emulsion binder comprises a water-soluble, film-forming amphoteric copolymer having in its molecule repeating units of the general formula: ##STR35## where n is a positive integer; R is the residue of an ethylenically unsaturated organic monomer; X is ##STR36## --S-- or --O--, where R 2 is hydrogen or lower alkyl; R 1 is lower alkylene, lower alkylene substituted by halogen, alkoxy or carboxy, cycloalkylene of 3 to 8 carbon atoms, or phenylene; and Y is ##STR37## where R 3 and R 4 are each hydrogen, lower alkyl or lower alkyl substituted by amino, or R 3 and R 4 together with the nitrogen atom to which they are attached form a 3- 8-membered saturated or unsaturated heterocyclic ring containing the nitrogen atom as the sole hetero atom or containing a second hetero atom selected from nitrogen, oxygen or sulfur, ##STR38## represents a 3-to 8-membered saturated or unsaturated heterocyclic ring containing the nitrogen atom in the ring as the sole hetero atom or containing a second hetero atom selected from nitrogen, oxygen or sulfur, ##STR39## where R 5 and R 6 are each hydrogen or lower alkyl, ##STR40## represents a 3- to 8-membered saturated or unsaturated heterocyclic ring containing the two nitrogen atoms as the sole heteroatoms and R 7 is lower alkylene, or -SR 8 , where R 8 is hydrogen or lower alkyl; or, when X is as defined above and Y is ##STR41## or --SR 8 , R 1 represents the atoms necessary to form a 3- to 8-membered heterocyclic ring with X and Y containing X and Y as the sole hetero atoms; and the quaternary ammonium salts thereof when Y is ##STR42## where R 3 and R 4 are lower alkyl or the ternary sulfonium salts thereof when Y is --S--R 8 , where R 8 is lower alkyl.

Claim 22

A method of preparing a photographic silver halide emulsion, comprising reacting a water-soluble silver salt with a water-soluble alkali metal halide in an aqueous solution of a water-soluble, film-forming amphoteric copolymer having in its molecule repeating units of the general formula: ##STR56## where n is a positive integer; R is the residue of an ethylenically unsaturated organic monomer; X is ##STR57## --S-- or --O--, where R 2 is hydrogen or lower alkyl; R 1 is lower alkylene, lower alkylene substituted by halogen, alkoxy or carboxy, cycloalkylene of 3 to 8 carbon atoms, or phenylene; and Y is ##STR58## where R 3 and R 4 are each hydrogen, lower alkyl or lower alkyl substituted by amino, or R 3 and R 4 together with the nitrogen atom to which they are attached form a 3- to 8-membered saturated or unsaturated heterocyclic ring containing the nitrogen atom as the sole hetero atom or containing a second hetero atom selected from nitrogen, oxygen or sulfur, ##STR59## represents a 3- to 8-membered saturated or unsaturated heterocyclic ring containing the nitrogen atom in the ring as the sole hetero atom or containing a second hetero atom selected from nitrogen, oxygen or sulfur, ##STR60## where R 5 and R 6 are each hydrogen or lower alkyl, ##STR61## represents a 3- to 8-membered saturated or unsaturated heterocyclic ring containing the two nitrogen atoms as the sole heteroatoms and R 7 is lower alkylene, or --SR 8 , where R 8 is hydrogen or lower alkyl; or when X is as defined above and Y is ##STR62## or --SR 8 , R 1 represents the atoms necessary to form a 3- to 8-membered saturated or unsaturated heterocyclic ring with X and Y and containing X and Y as the sole hetero atoms; and the quaternary ammonium salts thereof when Y is ##STR63## where R 3 and R 4 are lower alkyl or the ternary sulfonium salts thereof when Y is --S--R 8 , where R 8 is lower alkyl.

Claim 23

A method of preparing a photographic silver halide emulsion, comprising reacting a water-soluble silver salt with a water-soluble alkali metal halide in an aqueous solution of a water-soluble, film-forming amphoteric copolymer having in its molecule repeating units of the general formula: ##STR56## where n is a positive integer; R is the residue of an ethylenically unsaturated organic monomer; X is ##STR57## --S-- or --O--, where R 2 is hydrogen or lower alkyl; R 1 is lower alkylene, lower alkylene substituted by halogen, alkoxy or carboxy, cycloalkylene of 3 to 8 carbon atoms, or phenylene; and Y is ##STR58## where R 3 and R 4 are each hydrogen, lower alkyl or lower alkyl substituted by amino, or R 3 and R 4 together with the nitrogen atom to which they are attached form a 3- to 8-membered saturated or unsaturated heterocyclic ring containing the nitrogen atom as the sole hetero atom or containing a second hetero atom selected from nitrogen, oxygen or sulfur, ##STR59## represents a 3- to 8-membered saturated or unsaturated heterocyclic ring containing the nitrogen atom in the ring as the sole hetero atom or containing a second hetero atom selected from nitrogen, oxygen or sulfur, ##STR60## where R 5 and R 6 are each hydrogen or lower alkyl, ##STR61## represents a 3- to 8-membered saturated or unsaturated heterocyclic ring containing the two nitrogen atoms as the sole heteroatoms and R 7 is lower alkylene, or --SR 8 , where R 8 is hydrogen or lower alkyl; or when X is as defined above and Y is ##STR62## or --SR 8 , R 1 represents the atoms necessary to form a 3- to 8-membered saturated or unsaturated heterocyclic ring with X and Y and containing X and Y as the sole hetero atoms; and the quaternary ammonium salts thereof when Y is ##STR63## where R 3 and R 4 are lower alkyl or the ternary sulfonium salts thereof when Y is --S--R 8 , where R 8 is lower alkyl.