Non-filming dual additive developer

Claim 2

An electrostatographic developing composition comprising particles; said particles including (1) finely divided electroscopic toner material, (2) a minor portion, based upon the weight of said toner material of a stable, tough, substantially smearless, polymeric additive having an average particle size less than about the average particle size of said finely divided toner material, and (3) a minor portion, based on the weight of said toner material, of a finely divided nonsmearable abrasive material of a hardness greater than said polymeric additive and said toner material.

Claim 3

The developing composition of claim 1 wherein the toner material has an average particle size of less than about 30 microns.

Claim 4

The developing composition of claim 1 wherein the abrasive material has an average particle size between about 1 millimicron and about 500 millimicrons.

Claim 5

The developing composition of claim 1 wherein said composition comprises from about 0.1 percent to about 10 percent by weight of said polymeric additive based upon the weight of said toner material; and from about 0.01 percent to about 5 percent by weight of said abrasive material based upon the weight of said toner.

Claim 6

The developing composition of claim 1 wherein said polymeric additive is more electronegative than sulfur in the triboelectric series.

Claim 7

The developing composition of claim 1 wherein said polymeric additive is polyvinylidene fluoride.

Claim 8

The developing composition of claim 1 wherein said polymeric additive comprises spherical particles.

Claim 9

The developing composition of claim 1 wherein said abrasive material comprises submicron size colloidal silica.

Claim 10

The developing composition of claim 8 wherein said silica is silicon dioxide particles having surface silicon atoms chemically attached through silicon-oxygen-silicon bonding to silicon atoms having one to three organic groups directly attached thereto by silicon-carbon bonding.

Claim 11

The developing composition of claim 1 including from 10 to 1000 parts by weight of carrier particles per part of toner material, said carrier particles being grossly larger than said finely divided toner material.

Claim 12

An electrostatographic developing composition comprising particles; said particles including (1) finely divided electroscopic resin toner material, (2) a minor portion, based upon the weight of said toner material of a stable, tough, substantially smearless, polymeric additive having an average particle size less than about the average particle size of said finely divided toner material, said polymeric additive particles of a resin other than the resin of said toner material, and (3) a minor portion, based on the weight of said toner material, of a finely divided nonsmearable abrasive material of a hardness greater than said polymeric additive and said toner material.

Claim 13

An electrostatographic developing composition comprising particles; said particles including (1) finely divided electroscopic resin toner material, (2) a minor portion, based upon the weight of said toner material of a stable, tough, substantially smearless, polymeric additive having an average particle size less than about the average particle size of said finely divided toner material, said polymeric additive particles of a resin other than the resin of said toner material, and (3) a minor portion, based on the weight of said toner material, of a finely divided nonsmearable abrasive material of a hardness greater than said polymeric additive and said toner material.

Claim 14

An electrostatographic developing composition comprising particles; said particles including (1) finely divided electroscopic toner material, (2) from about 0.1 to about 10 percent, based upon the weight of said toner material of a stable, tough, substantially smearless, polymeric additive selected from the group consisting of polyvinylidene fluoride, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylchloride, polyvinylidine chloride, polyethylene, polypropylene, chlorinated polyethylene, chlorinated polyether, copolymers of tetrafluoroethylene and chlorotrifluoroethylene, copolymers of tetrafluoroethylene and hexafluoropropylene, copolymers of tetrafluoroethylene and vinylidine fluoride, copolymers of chlorotrifluoroethylene and vinylidine fluoride, copolymers of vinyl chloride and vinyl fluoride, copolymers of vinyl chloride and polyethylene, copolymers of vinyl chloride and polypropylene, and mixtures of the same having an average particle size less than about the average particle size of said finely divided toner material and (3) from about 0.01 to about 5 percent based upon on the weight of said toner material, of a finely divided nonsmearable abrasive material of a hardness greater than said polymeric additive and said toner material.

Claim 15

An electrostatographic developing composition comprising particles; said particles including (1) finely divided electroscopic toner material, (2) from about 0.1 to about 10 percent, based upon the weight of said toner material of a stable, tough, substantially smearless, polymeric additive selected from the group consisting of polyvinylidene fluoride, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylchloride, polyvinylidine chloride, polyethylene, polypropylene, chlorinated polyethylene, chlorinated polyether, copolymers of tetrafluoroethylene and chlorotrifluoroethylene, copolymers of tetrafluoroethylene and hexafluoropropylene, copolymers of tetrafluoroethylene and vinylidine fluoride, copolymers of chlorotrifluoroethylene and vinylidine fluoride, copolymers of vinyl chloride and vinyl fluoride, copolymers of vinyl chloride and polyethylene, copolymers of vinyl chloride and polypropylene, and mixtures of the same having an average particle size less than about the average particle size of said finely divided toner material and (3) from about 0.01 to about 5 percent based upon on the weight of said toner material, of a finely divided nonsmearable abrasive material of a hardness greater than said polymeric additive and said toner material.

Claim 16

A dry developer composition for electrostatographic image development comprising a toner of finely divided particles of a resin, an additive in an amount of from 0.1 to about 10 percent by weight of said toner of particles of a synthetic resin other than the resin of said toner, and an abrasive in an amount of from about 0.01 to about 5 percent by weight of said toner, said particles of additive and abrasive having an average size smaller than that of said toner particles, said particles of additive being at least one synthetic resin selected from the group consisting of polyvinylidene fluoride, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylchloride, polyvinylidine chloride, polyethylene, polypropylene, chlorinated polyethylene, chlorinated polyether, copolymers of tetrafluoroethylene and chlorotrifluoroethylene, copolymers of tetrafluoroethylene and hexafluoropropylene, copolymers of tetrafluoroethylene and vinylidine fluoride, copolymers of chlorotrifluoroethylene and vinylidine fluoride, copolymers of vinyl chloride and finyl fluoride, copolymers of vinyl chloride and polyethylene, copolymers of vinyl chloride and polypropylene, and mixtures of the same, and said particles of abrasive being selected from the group consisting of colloidal silica, surface modified organophilic silica, aluminum silicate, surface treated aluminum silicate, titanium dioxide, alumina, calcium carbonate, antimony trioxide barium titanate, calcium titanate, strontium titanate, CaSiO 3 , MgO, ZnO, ZrO 2 , and mixtures thereof.

Claim 17

A dry developer composition for electrostatographic image development comprising a toner of finely divided particles of a resin, an additive in an amount of from 0.1 to about 10 percent by weight of said toner of particles of a synthetic resin other than the resin of said toner, and an abrasive in an amount of from about 0.01 to about 5 percent by weight of said toner, said particles of additive and abrasive having an average size smaller than that of said toner particles, said particles of additive being at least one synthetic resin selected from the group consisting of polyvinylidene fluoride, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylchloride, polyvinylidine chloride, polyethylene, polypropylene, chlorinated polyethylene, chlorinated polyether, copolymers of tetrafluoroethylene and chlorotrifluoroethylene, copolymers of tetrafluoroethylene and hexafluoropropylene, copolymers of tetrafluoroethylene and vinylidine fluoride, copolymers of chlorotrifluoroethylene and vinylidine fluoride, copolymers of vinyl chloride and finyl fluoride, copolymers of vinyl chloride and polyethylene, copolymers of vinyl chloride and polypropylene, and mixtures of the same, and said particles of abrasive being selected from the group consisting of colloidal silica, surface modified organophilic silica, aluminum silicate, surface treated aluminum silicate, titanium dioxide, alumina, calcium carbonate, antimony trioxide barium titanate, calcium titanate, strontium titanate, CaSiO 3 , MgO, ZnO, ZrO 2 , and mixtures thereof.