Developer for electrophotography

Claim 2

A developer for electrophotography comprising toner particles and a carrier, said toner particles comprising colorant particles coated with an olefin resin having a melt index of 25 to 700 g/10 min, measured under a load of 2160±10 g, at 190°±0.4° C.

Claim 3

The developer for electrophotography as claimed in claim 1, wherein said toner particles consist essentially of pigment particles coated with said olefin resins, which toner particles have been prepared by a flushing method.

Claim 4

The developer for electrophotography as claimed in claim 1, wherein said toner particles have been prepared by a flushing method and consist essentially of pigment particles, said olefin resin and a humic acid component selected from the group consisting of humic acid, a salt of humic acid, and a humic acid derivative.

Claim 5

The developer for electrophotography as claimed in claim 1, wherein said olefin resin is selected from the group consisting of: (1) Ethylene-vinyl acetate-lauryl methacrylate copolymer resin (mole ratio 60:30:10), (2) Ethylene-vinyl acetate-methyl methacrylate-dimethylamino ethyl methacrylate copolymer resin (mole ratio 50:30:10:10), (3) Ethylene-vinyl acetate-ethyl acrylate-divinyl benzene copolymer resin (mole ratio 50:20:20:10), (4) Ethylene-vinyl acetate-methacrylic acid copolymer resin (mole ratio 50:40:10), (5) Propylene-vinyl acetate-lauryl methacrylate copolymer resin (mole ratio 60:30:10), (6) Propylene-vinyl acetate-acrylic acid copolymer resin (mole ratio 60:9:31), (7) Ethylene-ethyl acrylate copolymer resin (mole ratio 50:50), (8) Ethylene-butyl acrylate-acrylic acid copolymer resin (mole ratio 60:30:10), (9) Propylene-lauryl methacrylate-methacrylic acid copolymer resin (mole ratio 70:20:10), (10) Ethylene-acrylic acid-trimethylolpropane triacrylate copolymer resin (mole ratio 80:15:5), and (11) Propylene-ethyl laurate copolymer resin (mole ratio 50:50).

Claim 6

The developer for electrophotography as claimed in claim 2, wherein said pigment is selected from the group consisting of carbon black and organic pigments.

Claim 7

The developer for electrophotography as claimed in claim 1 in which said olefin resin is a copolymer comprised of a polyolefin main backbone chain having polar groups joined thereto and prepared by copolymerizing said polyolefin with a monomer having polar groups.

Claim 8

The developer for electrophotography as claimed in claim 1 in which said polyolefin resin has a bridge structure formed by a cross-linking agent or a radical initiator.

Claim 9

A developer for electrophotography as claimed in claim 2 in which said toner particles are free of an inorganic metal salt.

Claim 10

A developer for electrophotography as claimed in claim 3 in which said toner particles are free of an inorganic metal salt.

Claim 11

A developer for electrophotography as claimed in claim 2 in which said olefin resin is a terpolymer of (1) from 50 to 60 mole % of an olefin component selected from the group consisting of ethylene or propylene, (2) from 9 to 40 mole % of vinyl acetate and (3) from 10 to 31 mole % of acrylic acid, methacrylic acid or alkyl esters thereof.

Claim 12

A developer for electrophotography as claimed in claim 3 in which said olefin resin is a terpolymer of (1) from 50 to 60 mole % of an olefin component selected from the group consisting of ethylene or propylene, (2) from 9 to 40 mole % of vinyl acetate and (3) from 10 to 31 mole % of acrylic acid, methacrylic acid or alkyl esters thereof.