US4286037A — Electrostatic image one-component electrically co…

Claim 1

Independent Claim 156 words

Process for preparing developer powder consisting essentially of particles of thermoplastic resin having dispersed therein, with or without other additive, a substantially water-insoluble quaternary ammonium salt rendering said particles substantially electrically conductive, which process comprises providing an aqueous emulsion of minute thermoplastic resin particles, which emulsion contains in solution an ion that will react with a second ion to form said quaternary ammonium salt, and mixing said emulsion with a coagulant liquid that will coagulate said minute resin particles and contains said second ion in solution, thereby in the resultant mixture forming said minute resin particles into resin coagula of substantially greater size and reacting said ions to form said salt in and substantially uniformly throughout the coagula, said ions being respectively a quaternary ammonium ion and an organic acid anion that forms with said quaternary ammonium ion a quaternary ammonium salt having a solubility of less than 3% by weight in water at 25° C.

Claim 2

Dependent Claim 156 words

Process for preparing developer powder consisting essentially of particles of thermoplastic resin having dispersed therein, with or without other additive, a substantially water-insoluble quaternary ammonium salt rendering said particles substantially electrically conductive, which process comprises providing an aqueous emulsion of minute thermoplastic resin particles, which emulsion contains in solution an ion that will react with a second ion to form said quaternary ammonium salt, and mixing said emulsion with a coagulant liquid that will coagulate said minute resin particles and contains said second ion in solution, thereby in the resultant mixture forming said minute resin particles into resin coagula of substantially greater size and reacting said ions to form said salt in and substantially uniformly throughout the coagula, said ions being respectively a quaternary ammonium ion and an organic acid anion that forms with said quaternary ammonium ion a quaternary ammonium salt having a solubility of less than 3% by weight in water at 25° C.

Claim 3

Dependent Claim 43 words

Process according to claim 1, said coagulant liquid also containing in finely dispersed state as additive an organic dye or fine solid particles, or both; and by said mixing dispersing said additive substantially uniformly throughout said coagula as the coagula are being formed.

Claim 4

Dependent Claim 51 words

Process according to claim 1 or 2, the resin particles of said emulsion being of below 1 micrometer in size; and controlling the coagulation conditions so that the resin particles of said emulsion are formed into coagulated particles mainly in the size range of between about 10 and about 45 micrometers.

Claim 5

Dependent Claim 165 words

Process for preparing a developer powder consisting essentially of thermoplastic resin particles containing additive material finely dispersed therein and having a specific resistance of between approximately 10 5 and 10 11 ohm.cm, which process comprises forming an aqueous emulsion of minute thermoplastic resin particles by emulsion-polymerization of at least one monomer in an aqueous medium in the presence of an emulsifier that provides in said medium an ion that will react with a second ion to form a substantially water-insoluble quaternary ammonium salt; while stirring vigorously, adding said emulsion gradually to a water-miscible coagulant liquid that will coagulate the emulsion-polymerized resin particles of said emulsion and contains in solution a substance which provides said second ion, thereby coagulating said minute particles into resin coagula of substantially greater size having trapped and uniformly distributed therein fine particles of said quaternary ammonium salt formed in situ by reaction of said ions in the coagulation mixture; and thereafter separating said coagula from the liquid of the coagulation mixture.

Claim 6

Dependent Claim 165 words

Process for preparing a developer powder consisting essentially of thermoplastic resin particles containing additive material finely dispersed therein and having a specific resistance of between approximately 10 5 and 10 11 ohm.cm, which process comprises forming an aqueous emulsion of minute thermoplastic resin particles by emulsion-polymerization of at least one monomer in an aqueous medium in the presence of an emulsifier that provides in said medium an ion that will react with a second ion to form a substantially water-insoluble quaternary ammonium salt; while stirring vigorously, adding said emulsion gradually to a water-miscible coagulant liquid that will coagulate the emulsion-polymerized resin particles of said emulsion and contains in solution a substance which provides said second ion, thereby coagulating said minute particles into resin coagula of substantially greater size having trapped and uniformly distributed therein fine particles of said quaternary ammonium salt formed in situ by reaction of said ions in the coagulation mixture; and thereafter separating said coagula from the liquid of the coagulation mixture.

Claim 7

Dependent Claim 30 words

Process according to claim 4, said at least one monomer comprising styrene and butyl acrylate in quantities whereby the thermoplastic resin formed in said emulsion is a styrene-butyl acrylate copolymer.

Claim 8

Dependent Claim 36 words

Process according to claim 4, one of said emulsifier and said substance being a water-soluble quaternary ammonium salt and the other of them being a water-soluble salt of an organic acid having a hydrophobic hydrocarbon group.

Claim 9

Dependent Claim 23 words

Process according to claim 4, said emulsion-polymerization being effected so as to form the emulsion-polymerized resin particles with particle sizes below 1 micrometer.

Claim 10

Dependent Claim 33 words

Process according to claim 4, said water-miscible liquid being selected from the group consisting of aqueous electrolyte solutions, water-miscible organic solvents and mixtures of water or aqueous electrolyte solutions with water-miscible organic solvents.

Claim 11

Dependent Claim 46 words

Process according to claim 4, said emulsifier and said substance being present, respectively, in said aqueous medium and said coagulant liquid, or vice versa, in approximately stoichiometric quantities sufficient to form in said coagula between about 8 and 35% by weight of said quaternary ammonium salt.

Claim 12

Dependent Claim 34 words

Process according to claim 5, 6, 7, 8, or 9, said coagulating being effected under conditions whereby said coagula are formed with particle sizes predominantly in the range between about 10 and 45 micrometers.

Claim 13

Dependent Claim 30 words

Process according to claim 10, and finally drying said coagula and separating from among the resultant dried particles those which have sizes larger or smaller than a desired size range.

Claim 14

Dependent Claim 188 words

Process according to claim 4, said at least one monomer comprising styrene and butyl acrylate in quantities whereby the thermoplastic resin formed in said emulsion is a styrene-butyl acrylate copolymer; said emulsion-polymerization being effected so as to form said emulsion-polymerized resin particles with particle sizes below 1 micrometer; said coagulant liquid comprising water and a water-miscible organic solvent; one of said emulsifier and said substance being a water soluble quaternary ammonium salt and the other of them being a water-soluble salt of an organic acid having a hydrophobic hydrocarbon group; said water-soluble salts being present, respectively, in said aqueous medium and said coagulant liquid, or vice versa, in approximately stoichiometric quantities sufficient to form in said coagula between about 8 and 35% by weight of said substantially water-insoluble quaternary ammonium salt; said coagulating being effected under conditions whereby said coagula are formed with particle sizes predominantly in the range of between about 10 and 45 micrometers; and, after said separating, drying said coagula and separating from among the dried particles those which have sizes larger or smaller than a certain size range desired for inductively attractable developer powder.

Claim 15

Dependent Claim 60 words

Process according to claim 12, said coagulant liquid having dispersed therein finely divided additive material comprising fine magnetically attractable particles; and as said coagula are being formed in said mixture trapping said additive material in and substantially uniformly throughout the coagula in a quantity sufficient to render said dried particles transportable by magnetic attraction thereof to a magnetic powder applicator.

Claim 16

Dependent Claim 40 words

Process according to claim 12, said coagulant liquid having dispersed therein finely divided additive material comprising fine carbon black; and as said coagula are being formed in said mixture trapping said additive material in and substantially uniformly throughout the coagula.

Claim 17

Dependent Claim 32 words

Process according to claim 13, said additive material also comprising fine carbon particles in a quantity sufficient to enhance the conductivity but not exceeding 15% of the weight of said dried particles.

Claim 18

Dependent Claim 68 words

Developer powder comprising electrically conductive thermoplastic resin particles prepared by the process of claim 4, said particles having a specific resistance of between approximately 10 5 and 10 11 ohm.cm and consisting essentially of dried coagula of emulsion-polymerized thermoplastic resin particles having distributed therein substantially uniformly throughout the coagula, with or without other fine additive particles, fine precipitated-in-situ particles of a substantially water-insoluble electrically conductive quaternary ammonium salt.

Claim 19

Dependent Claim 79 words

Developer powder comprising electrically conductive thermoplastic resin particles prepared by the process of claim 12, said particles having a specific resistance of between approximately 10 5 and 10 11 ohm.cm and consisting essentially of dried coagula of emulsion-polymerized particles of a styrene-butyl acrylate copolymer having distributed therein substantially uniformly throughout the coagula, with or without other fine additive particles, between about 8 and 35% by weight of fine precipitated-in-situ particles of a substantially water-insoluble electrically conductive quaternary ammonium salt.

Claim 20

Dependent Claim 60 words

Developer powder according to claim 17, said coagula also having substantially uniformly distributed therein finely divided additive particles comprising fine magnetically attractable particles in a quantity rendering said dried coagula transportable by magnetic attraction thereof to a powder applicator and fine carbon particles in a quantity enhancing the conductivity of said dried coagula but not exceeding 15% of their weight.

Claim 21

Dependent Claim 73 words

Developer powder comprising thermoplastic resin particles prepared by the process of claim 1, said particles having a specific resistance of between about 10 5 and about 10 11 ohm.cm and consisting essentially of dried coagula of emulsion-polymerized thermoplastic resin particles having distributed therein substantially uniformly throughout the coagula, with or without other fine additive particles, at least 8% by weight of fine precipitated-in-situ particles of an electrically conductive substantially water-insoluble quaternary ammonium salt.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1984-08-24	1985-02-23	1985-08-25	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1988-08-24	1989-02-23	1989-08-25	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1992-08-24	1993-02-23	1993-08-25	$7700.00	Window Closed / Lapsed

Electrostatic image one-component electrically conductive thermoplastic resin containing powdered developer prepared by coagulation in emulsion

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