Abstract: In a negatively chargeable toner having i) negatively chargeable toner particles containing at least a binder resin, a colorant and a vinyl copolymer and ii) an inorganic fine powder, the negatively chargeable toner has a weight-average particle diameter of from 4 &mgr;m to 12 &mgr;m and contains, in particle size distribution of the toner, less than 50% by volume of particles of 10.1 &mgr;m or more in particle diameter, and the vinyl copolymer is a vinyl copolymer obtained by copolymerizing a monomer composition which contains at least i) a vinyl monomer such as an N-substituted acryl- or methacrylamide or a ring-structure acryl- or methacrylamide and ii) a vinyl monomer having as a functional group a carboxyl group or a carboxyl group made into salt structure. An image-forming method and a process cartridge make use of such a negatively chargeable toner.

Abstract: A process for lowering the charge/mass (Q/m) ratio of toner particles formed by limited coalescence includes: forming an organic phase containing a water-immiscible liquid, pigment, a quaternary ammonium tetraphenylborate salt, and a polymeric material selected from the group consisting of an acrylic resin, a methacrylic resin, a styrene-acrylic resin, a styrene-methacrylic resin, a polyamide, and a polyester. The organic phase is dispersed in an aqueous phase containing a solid colloidal stabilizer, and a suspension of small droplets of the organic phase is formed in the aqueous phase by high shear agitation. The water-immiscible liquid is removed from the small droplets, thereby forming a suspension in the aqueous phase of small, non-spherically shaped solid particles, which are separated from the aqueous phase and dried. The quaternary ammonium tetraphenylborate salt is included in the organic phase in an amount effective for lowering the charge/mass (Q/m) ratio of the toner particles.

Abstract: Disclosed are marking particles comprising a resin, a chelating agent, and a spiropyran material which is of the formula The marking particles are prepared by an emulsion aggregation process.

Abstract: A toner is formed of toner particles each comprising at least a binder resin, a colorant and a wax, and inorganic fine powder. The toner is characterized by (a) containing a sulfur-containing polymer, and (b) showing dielectric loss tangent (tan&dgr;) values at 100 kHz assuming a maximum of 2.5×10−2 to 8×10−2 in a temperature range of 100 to 130° C. Because of the combination of the features (a) and (b), the toner can exhibit a good combination of developing performances and fixing performances.

Abstract: A magnetic toner is formed of magnetic toner particles each comprising a binder resin, an iron oxide, a sulfur-containing polymer, and inorganic fine powder blended with the magnetic toner particles, the toner having a weight-average particle size (D4) of 3-10 &mgr;m, and either (a) an average circularity of at least 0.970, and a magnetization of 10-50 Am2/kg (emu/g) at a magnetic field of 79.6 kA/m (1000 oersted), or (b) toner particles which retain carbon in an amount of A and iron in an amount of B at surfaces thereof, satisfying: B/A<0.001, and containing at least 50% by number of magnetic toner particles of D/C≦0.02, wherein C represents a particle projection area-equivalent circle diameter and D represents a minimum distance between a surface of the magnetic toner particle and iron oxide particles contained therein.

Abstract: A negative-chargeability control resin containing a specific vinyl copolymer imparts stable chargeability to toner. The vinyl copolymer is obtainable by copolymerizing a monomer composition which contains at least i) a vinyl monomer (A) as exemplified by N-acryloylmorpholine, N-isopropylacrylamide, N-methylmethacrylamide, N-butoxymethylacrylamide or N-t-butylacrylamide, or a vinyl monomer (B) as exemplified by vinyl butyrate, vinyl 2-ethylhexanoate, vinyl benzoate, vinyl monochloroacetate pivarate, and ii) a vinyl monomer (C) having as a functional group a carboxyl group or a carboxyl group made into salt structure.

Abstract: A developer includes developer main particles and abrasive particles added to the developer main particles. The developer main particles include at least a resin material and a coloring material. The abrasive particles and the developer main particles are opposite in polarity when they are charged. The abrasive particles have an average diameter in the range of 50 to 5000 nm and preferably in the range of 150 to 2000 nm. A fluidity-adding agent is added to the developer main particles. The fluidity-adding agent has a diameter in the range of 5 to 40 nm. The fluidity-adding agent is at least 0.1 weight parts with respect to the developer main particles, and the abrasive particles are in the range of 0.02 to 1.2 weight parts.

Abstract: In order to control the filming, a developer comprises developer primary particles, each comprising at least a resin and a colorant and an additive agent added to the developer primary particles and having a particle diameter smaller than that of the developer primary particles, wherein an extrication amount of the additive agent in the developer primary particles is smaller than 5.2×10−5 part by weight with respect to the developer primary particles.

Abstract: A toner for developing an electrostatic image, including a colorant, a binder resin comprising a modified polyester, and fine resin particles having a weight average particle diameter of 50 to 300 nm and being present on an outer surface of the toner, wherein the toner has a BET specific surface area of 1.5 to 4.0 m2/g.

Abstract: Disclosed is a toner comprising particles of a polyester resin, an optional colorant, and polypyrrole, wherein said toner particles are prepared by an emulsion aggregation process. Another embodiment of the present invention is directed to a process which comprises (a) generating an electrostatic latent image on an imaging member, and (b) developing the latent image by contacting the imaging member with charged toner particles comprising a polyester resin, an optional colorant, and polypyrrole, wherein said toner particles are prepared by an emulsion aggregation process.

Abstract: A toner for developing an electrostatic latent image, containing a colorant and a binder resin composed of two different resins (A) and (B), wherein resin (A) is substantially free of tetrahydrofuran insolubles, is selected from polyester resins and polyol resins and has such a molecular weight distribution according to gel permeation chromatography that (a) a main peak is present in a molecular weight of 3000 to 9,000 and (b) that portion of resin (A) having a molecular weight of 500 or less accounts for 4% or less based on a total weight of resin (A), wherein resin (B) is substantially free of tetrahydrofuran insolubles and is a polyester resin containing a diol component represented by the formula (1): 1

Abstract: Toner particles including a binder resin; a colorant; and a particulate resin which is present at least on a surface of the toner particles and which has a glass transition temperature of form 50 to 90° C., wherein a ratio (Dv/Dn) of a volume average particle diameter (Dv) of the toner particles to a number average particle diameter (Dn) thereof is from 1.00 to 1.40 and the surface of the toner particles is covered with the particulate resin at a covering ratio of from 1 to 90 %. A method for manufacturing the toner particles is provided. A developer including a toner including the toner particles is provided. A developing method using a toner including the toner particles is provided. A toner container containing the toner particles is provided.

Abstract: A toner characterized by improved fixing performances with no or minimum oil application is formed of: (i) a binder resin, (ii) a colorant, (iii) a hydrocarbon wax, (iv) a resin composition formed by copolymerization of a styrenic monomer together with at least one of nitrogen-containing vinyl monomers, carboxyl group-containing monomers, hydroxyl group-containing monomers and (meth)acrylate ester monomers, in the presence of a hydrocarbon unit; and (v) an organometallic compound. The binder resin (i) comprises a polyester component in a proportion of at least 60 wt. % of the binder resin. The toner has a GPC molecular weight distribution including a weight-average molecular weight (Mw) of at least 4.0×104 an a ratio Mw/Mn of at least 50 between the Mw and a number-average molecular weight (Mn).

Abstract: Disclosed is a toner comprising particles of a resin and an optional colorant, said toner particles having coated thereon a polypyrrole. Another embodiment of the present invention is directed to a process which comprises (a) generating an electrostatic latent image on an imaging member, and (b) developing the latent image by contacting the imaging member with charged toner particles comprising a resin and an optional colorant, said toner particles having coated thereon a polypyrrole.

Abstract: Electrostatic charge image developing toner allows to design the toner characteristics such as chargeability, flowability, stability in time and environmental stability uniform among the toners of different colors. The toner has a small particle size enough for enabling uniform dispersion and being excellent in color saturation and transparency. The toner also shows higher contribution to the environmental security. The toner includes a coloring agent of which at least a part of the surface is covered with polyhydroxyalkanoate (PHA). The toner is produced by dispersing the coloring agent in aqueous medium, then fixing PHA synthesizing enzyme to the coloring agent dispersed in the aqueous medium, then adding 3-hydroxyacyl CoA, and executing a PHA synthesizing reaction to cover at least a part of the surface of the coloring agent with PHA. The toner thus obtained is used for an image forming method.

Abstract: The present invention provides a novel PHA comprising a unit containing thioether with high reactivity, and its production method. The present invention also provides polyhydroxyalkanoate (PHA) comprising units having defined chemical formulas (1) and (2), and at least one of four units having defined chemical formulas (3), (4), (5) and (6); its production method; a charge control agent containing the PHA; a toner binder containing the charge control agent; an electrostatic latent image developing toner; and an image forming method and an image forming apparatus using the electrostatic latent image developing toner.

Abstract: A toner having a good chargeability stable against an environmental change is formed of toner particles each comprising at least a binder resin, a colorant, a release agent and a sulfur-containing polymer, and an external additive. The toner particles contain 100 to 30,000 ppm by weight thereof of at least one stabilizer element selected from the group consisting of magnesium, calcium, barium, zinc, aluminum and phosphorus. The toner particles may preferably be produced by suspension polymerization of a monomer composition containing the sulfur-containing polymer in an aqueous medium containing a dispersion stabilizer having the stabilizer element.

Abstract: A toner for development of electrostatic images, comprising at least a binder resin, a colorant and a charge control agent, wherein the charge control agent contains a positive charge control resin (A) composed of a polymer having a weight average molecular weight of 1,000 to 100,000 and a functional group which brings positively charging ability, and a negative charge control resin (B) composed of a polymer having a weight average molecular weight of 1,000 to 100,000 and a functional group which brings negatively charging ability. The toner is excellent in flowability, shelf stability and charge properties, and provides images excellent in image quality.

Abstract: A charge-controlling agent comprising a polyamine having a repeating structure represented by the following general formula (I): The symbols in the formula are defined in the specification. Also disclosed is a toner using the charge-controlling agent.

Abstract: A toner composition comprising a primary resin and at least one additional polymeric component is improved by reactive compatibilization of the additional polymeric component and the resin. For example, effective amounts of a functional secondary resin and a functional silicone oil having functionality reactive therewith are included and mixed by extrusion so as to reduce or eliminate speckling in printing with the toner and the improve toner powder flow.

Abstract: A toner has toner particles containing at least a binder resin, a colorant and a sulfur-containing compound selected from the group consisting of a sulfur-containing polymer and a sulfur-containing copolymer. The toner has a weight-average particle diameter of from 5 &mgr;m to 12 &mgr;m, and the toner has, in its particles of 3 &mgr;m or larger in diameter, at least 90% by number of particles with a circularity of 0.900 or higher, and has a specific relationship between the cut rate Z and the toner weight-average particle diameter X and a specific relationship between the number-based cumulative value Y of particles with a circularity of 0.950 or higher and the toner weight-average particle diameter X. Also disclosed are an image-forming method and a process cartridge which make use of the toner.

Abstract: A dispersing agent for a pigment, comprising a specific compound having a structure wherein a phthalocyanine type molecular skeleton which is adsorptive on the pigment and an oligomer unit or polymer unit which prevents re-agglomeration of the pigment to bring out the effect of dispersion are covalently bonded, and having affinity for a medium or a solvent. Also disclosed are a pigment-dispersion composition containing the dispersing agent, a toner prepared using a pigment having been treated with the dispersing agent, and a process for producing such a toner.

Abstract: A toner is formed of toner particles each comprising at least a binder resin, a colorant and a wax, and inorganic fine powder. The toner is characterized by (a) containing a sulfur-containing polymer, and (b) showing dielectric loss tangent (tan&dgr;) values at 100 kHz assuming a maximum of 2.5×10−2 to 8×10−2 in a temperature range of 100 to 130° C. Because of the combination of the features (a) and (b), the toner can exhibit a good combination of developing performances and fixing performances.

Abstract: A toner for electrostatic image development, which comprises a binder resin, a colorant and a charge control resin, wherein the charge control resin is a copolymer composed a vinyl monomer unit and a quaternary ammonium salt group-containing (meth)acrylate monomer unit and has a glass transition temperature of 40 to 75° C., and a production process thereof.

Abstract: In a magnetic one-component toner containing at least a binder resin, a charge control resin, and a magnetic powder, the charge control resin has a weight-average molecular weight of 1.5×104 or less, contains 8 to 15% by weight of functional groups, and is added in 5 to 20 parts by weight to 100 parts by weight of the binder resin. This makes the toner highly safe for humans and the environment and excellent in fixability and electric chargeability.

Abstract: A toner including at least a binder resin; a colorant; and a charge controlling agent, in which the binder resin includes at least a polyester resin having a molecular weight distribution such that components having a molecular weight not greater than 500 are included in an amount of 4% by weight and at least a peak is present in a range of from 3,000 to 9,000 when measured by Gel Permeation Chromatography. In addition, the binder resin does not include a tetrahydrofuran-insoluble compound and the charge controlling agent is a resin charge controlling agent including at least units obtained from a monomer including a sulfonate group; an aromatic monomer including an electron absorption group; and an acrylic ester and/or a methacrylic ester monomer.

Abstract: A process for forming non-spherical toner particles by limited coalescence comprises: forming an organic phase comprising a polymeric material, a pigment, a quaternary ammonium tetraphenylborate salt, and a water-immiscible liquid; dispersing the organic phase in an aqueous phase containing a solid colloidal stabilizer; forming a suspension of small droplets of the organic phase in the aqueous phase by high shear agitation; removing the water-immiscible liquid from the small droplets, thereby forming a suspension of small solid particles in the aqueous phase; and separating and drying the solid particles, which are toner particles having a non-spherical shape.

Abstract: In a toner containing at least a binder resin, a pigment and a pigment dispersant, the pigment dispersant has a structure wherein a quinacridone molecular skeleton which is readily adsorptive on the colorant pigment and an oligomer or polymer which has good affinity for the solvent and for the resin serving as a toner binder are covalently bonded. Also disclosed is a process for producing the toner.

Abstract: A toner for development of electrostatic images comprising carbon black as a colorant, wherein the carbon black has the following features:

Abstract: Disclosed is a toner comprising particles of a resin and an optional colorant, said toner particles having coated thereon a polypyrrole. Another embodiment of the present invention is directed to a process which comprises (a) generating an electrostatic latent image on an imaging member, and (b) developing the latent, image by contacting the imaging member with charged toner particles comprising a resin and an optional colorant, said toner particles having coated thereon a polypyrrole.

Abstract: Disclosed is a toner comprising particles of a vinyl resin, an optional colorant, and poly(3,4-ethylenedioxypyrrole), wherein said toner particles are prepared by an emulsion aggregation process. Another embodiment of the present invention is directed to a process which comprises (a) generating an electrostatic latent image on an imaging member, and (b) developing the latent image by contacting the imaging member with charged toner particles comprising a vinyl resin, an optional colorant, and poly(3,4-ethylenedioxypyrrole), wherein said toner particles are prepared by an emulsion aggregation process.

Abstract: In a toner containing at least a binder resin, a pigment and a pigment dispersant, the pigment dispersant has a structure wherein a quinacridone molecular skeleton which is readily adsorptive on the colorant pigment and an oligomer or polymer which has good affinity for the solvent and for the resin serving as a toner binder are covalently bonded. Also disclosed is a process for producing the toner.

Abstract: The present invention relates to the use of wax-coated pigment granules as colorants in electrophotographic toners and developers, powder coating materials, inkjet inks, electret fibers, and color filters, wherein the coated pigment granules have a particle size of between 0.05 and 5 mm and a wax content of from 1 to 50% by weight, based on the overall weight of the coated pigment granules.

Abstract: A charge-controlling agent comprising a polyamine having a repeating structure represented by the following general formula (I): 1

Abstract: A toner has toner particles containing at least a binder resin, a colorant and a sulfur-containing compound selected from the group consisting of a sulfur-containing polymer and a sulfur-containing copolymer. The toner has a weight-average particle diameter of from 5 &mgr;m to 12 &mgr;m, and the toner has, in its particles of 3 &mgr;m or larger in diameter, at least 90% by number of particles with a circularity of 0.900 or higher, and has a specific relationship between the cut rate Z and the toner weight-average particle diameter X and a specific relationship between the number-based cumulative value Y of particles with a circularity of 0.950 or higher and the toner weight-average particle diameter X. Also disclosed are an image-forming method and a process cartridge which make use of the toner.

Abstract: The electrophotographic toner according to the present invention comprises a binder resin, a colorant, and a negative charge control agent. The binder resin is polyester and/or polyol. The negative charge control agent comprises components which are (1) sulfonic-acid containing monomers, (2) aromatic monomers having electron-withdrawing groups, and (3) acrylate monomers and/or methacrylate monomers. In particular, substituted phenyl maleimides and substituted phenyl itaconimides are prefereably used as the aromatic monomers. Moreover, n-butyl (meth)acrylates and 2-ethylhexyl (meth)acrylates are prefereably used as the acrylate monomers and/or methacrylate monomers.

Abstract: Disclosed is a toner comprising particles of a polyester resin, an optional colorant, and poly(3,4-ethylenedioxypyrrole), wherein said toner particles are prepared by an emulsion aggregation process. Another embodiment of the present invention is directed to a process which comprises (a) generating an electrostatic latent image on an imaging member, and (b) developing the latent image by contacting the imaging member with charged toner particles comprising a polyester resin, an optional colorant, and poly(3,4-ethylenedioxypyrrole), wherein said toner particles are prepared by an emulsion aggregation process.

Abstract: A magnetic toner capable of exhibiting stable chargeability regardless of environmental change is formed of magnetic toner particles each comprising at least a binder resin, an iron oxide and a sulfur-containing polymer, and inorganic fine powder blended with the magnetic toner particles. The magnetic toner is also provided with good developing performance and high transferability by satisfying a weight-average particle size (D4) of 3-10 &mgr;m, an average circularity of at least 0.970, and a magnetization of 10-50 Am2/kg (emu/g) at a magnetic field of 79.6 kA/m (1000 oersted). The magnetic toner is further characterized in that the magnetic toner particles retain carbon in an amount of A and iron in an amount of B at surfaces thereof as measured by X-ray photoelectron spectroscopy, satisfying: B/A<0.001, and the magnetic toner contains at least 50% by number of magnetic toner particles satisfying a relationship of D/C≦0.

Abstract: A toner containing toner particles and an inorganic fine powder; the toner particles containing at least a binder resin, a colorant, a sulfur-containing resin, and a wax; the binder resin containing a hybrid resin component containing a vinyl type polymer unit and a polyester unit, and the sulfur-containing resin being a resin selected from the group consisting of sulfur-containing polymers and sulfur-containing copolymers

Abstract: Disclosed are marking particles comprising a first polymer, a second polymer, a chelating agent, and a spiropyran material of the formula wherein n is an integer representing the number of repeat —CH2— units and R is —H or —CH═CH2. The marking particles comprise a core containing the first polymer in which is dispersed the chelating agent and the spiropyran and encapsulated within a shell of the second polymer formulated by an interfacial polymerization.

Abstract: A toner for development of electrostatic images, obtained by subjecting a polymerizable monomer composition containing at least a colorant, a polymerizable monomer and a charge control agent to suspension polymerization in an aqueous medium containing a dispersing agent, wherein (a) the dispersing agent is a cationic inorganic dispersing agent; and (b) the charge control agent is a quaternary ammonium salt group-containing copolymer comprising a vinyl aromatic hydrocarbon unit, a (meth)acrylate unit and a quaternary ammonium salt group-containing (meth)acrylate unit, having a weight average molecular weight of 25,000 to 40,000 in terms of polystyrene as measured by gel permeation chromatography using tetrahydrofuran and containing the quaternary ammonium salt group-containing (meth)acrylate unit in a proportion of 1 to 15 wt. %, and a production process thereof.

Abstract: A toner composition comprising a primary resin and at least one additional polymeric component is improved by reactive compatibilization of the additional polymeric component and the resin. For example, effective amounts of a functional secondary resin and a functional silicone oil having functionality reactive therewith are included and mixed by extrusion so as to reduce or eliminate speckling in printing with the toner and to improve toner powder flow.

Abstract: A toner composition comprising a primary resin and at least one additional polymeric component is improved by reactive compatibilization of the additional polymeric component and the resin. For example, effective amounts of a functional secondary resin and a functional silicone oil having functionality reactive therewith are included and mixed by extrusion so as to reduce or eliminate speckling in printing with the toner and to improve toner powder flow.

Abstract: A toner for development of electrostatic images, comprising at least a binder resin, a colorant and a charge control agent, wherein the charge control agent is a polar resin composed of a copolymer of a vinyl monomer and SO3X (X=H or alkali metal) group-containing (meth)acrylamide and having an SO3X group-containing (meth)acrylamide unit content of 0.1 to 10 wt. % and a weight average molecular weight of 17,000 to 25,000, and a production process of the toner.

Abstract: A toner composition comprised of binder, colorant, and a surface additive of a coated silica and wherein said silica possesses a BET surface area, in m2/g of from about 35 to about 65, a bulk density, in grams/liter, of from about 40 to about 60, and and wherein the size diameter determined from the BET measurement is from about 20 to about 100 nanometers.