Abstract: Carrier comprised of a mixture of insulating carrier particles and conductive carrier particles.

Abstract: Carrier comprised of a mixture of insulating carrier particles and conductive carrier particles.

Abstract: A magnetic carrier exhibiting excellent durability against mechanical impact as exerted by vibration and capable of exhibiting a stable charging performance in electrophotography is provided.

Abstract: An electrophotographic developer and a process for forming an image are provided in that the fixing can be conducted at a lower temperature than the conventional technique, and that are excellent in the powder storage stability, the anti-blocking property and the image storage stability after fixing without impairing the density, the coloring property and the transparency of the image after fixing, and further have appropriate electric charging property without any problem of fogging or cloud with excellent maintenance property of electric charge. The electrophotographic developer contains a toner for developing an electrostatic image containing a coloring agent and a binder resin containing, as a main component, a crystalline resin having a melting point of about from 60 to 120° C., and a carrier having a resin film containing a nitrogen-containing resin on a surface thereof. The process for forming an image is carried out by using the electrophotographic developer.

Abstract: A carrier for electrophotographic developer, including a core material and a resin layer formed on the surface of the core material, wherein the resin layer has a plastic deformation degree not less than 0.5 &mgr;m and an elastic deformation degree not less than 0.5 &mgr;m. The resin layer is preferably prepared by crosslinking a mixture including an acrylic resin having a reactive hydroxyl group and at least one of a perfectly-alkylated melamine compound and a perfectly-alkylated guanamine compound.

Abstract: A carrier for an image developer for electrophotography, including core particles, and a coating layer covering each of the core particles, wherein the core particles have a weight average particle diameter of Dv which is 25-45 &mgr;m and a number average particle diameter of Dp which meets with the following condition:

Abstract: Magnetic particles having an average particle size of 10 to 200 &mgr;m, comprising: magnetic core particles; and a coating layer formed on each surface of said magnetic core particles, comprising at least one metal alkoxide represented by the general formula (I): (RO)nM  (I)  wherein R is a C1 to C16 alkyl group; M is Al, Ti, Na, K, Ca, Zn or Fe; and n is an integer of 1 to 4, at least one silane-based coupling agent, and a silicone resin. Such magnetic particles have an excellent durability and a stable charging property.

Abstract: A carrier for the development of an electrostatic latent image, comprising a core material and a resin coating the core material therewith, wherein the coating resin comprises a copolymer of at least four kinds of monomers including: (1) a monomer containing a carboxyl group; (2) an acrylic acid alkylester monomer or methacrylic acid alkylester monomer, containing a C1-C3 linear alkyl group; (3) an acrylic acid alkylester monomer or methacrylic acid alkylester monomer, containing a C4-C10 linear alkyl group or C3-C10 branched alkyl group; and (4) a monomer containing fluorine. Also disclosed is a two-component developer for the development of an electrostatic latent image, comprising a toner and the carrier.

Abstract: A carrier for an image developer for electrophotography, including core particles, and a coating layer covering each of the core particles, wherein the core particles have a weight average particle diameter of Dv which is 25-45 &mgr;m and a number average particle diameter of Dp which meets with the following condition: 1≦Dv/Dp≦1.3, wherein the core particles have such a particle size distribution that particles having a particle diameter of less than 44 &mgr;m is at least 70% by weight and particles having a particle diameter of less than 22 &mgr;m is not more than 7% by weight.

Abstract: A method for use in two-components electrostatic image developers is disclosed, in which secure separation of a carrier coating resinous materials from a core magnetic material is achieved without affecting the properties of the core materials through process steps benign to the environment in super- or sub-critical water compositions under the conditions of a temperature of 300° C. or more and a pressure of 20 MPa. The core magnetic material is subsequently recycled for forming carrier. This method may also be useful for processing waste including magnetic materials with silicone resin coating.

Abstract: The present invention relates to a developer for electrostatic image development comprising: a toner for electrostatic image development which comprises a resin and a colorant; and a carrier formed by a carrier core material and a resin layer including a resistance control agent which is formed on the surface of the carrier core material, wherein the resin layer of the carrier has a concentration gradient of the resistance control agent toward the thickness direction of the resin layer, a concentration of the resistance control agent is the highest in the vicinity of the carrier core material, and is gradually lowered toward the surface of the resin layer, and the resistance control agent is present on the surface of the resin layer, as well as relates to an image forming method, wherein it comprises a step of developing an electrostatic image at a developing speed of 20 m/min or higher, by means of employing the developer for electrostatic image development.

Abstract: A charge-providing member or carrier for the development of an electrostatic latent image comprising a resin coat layer provided on a core material, characterized in that the coating resin comprises a (meth)acrylic acid alkyl ester copolymer containing as copolymerizing components a (meth) acrylic acid alkyl ester containing a branched alkyl group having 4 or more carbon atoms and a (meth) acrylic acid alkyl ester containing a fluorine-containing alkyl group, a developer comprising such a carrier, and a sleeve for carrying such a developer.

Abstract: The present invention provides an electrophotographic developer which reduces toner contamination on the surface of a developer carrier even when a development effective range is narrowed and which is stabilized in an image quality in every environmental situation and has a long life and a low cost and an image-forming method using the same.

Abstract: An electrophotographic developer and a process for forming an image are provided in that the fixing can be conducted at a lower temperature than the conventional technique, and that are excellent in the powder storage stability, the anti-blocking property and the image storage stability after fixing without impairing the density, the coloring property and the transparency of the image after fixing, and further have appropriate electric charging property without any problem of fogging or cloud with excellent maintenance property of electric charge. The electrophotographic developer contains a toner for developing an electrostatic image containing a coloring agent and a binder resin containing, as a main component, a crystalline resin having a melting point of about from 60 to 120° C., and a carrier having a resin film containing a nitrogen-containing resin on a surface thereof. The process for forming an image is carried out by using the electrophotographic developer.

Abstract: The present invention relates to a binder-type carrier comprising a copolymer obtained by using an ethylenic unsaturated nitrile as its constituent monomer, an amino-modified silicone oil, and magnetic particles.

Abstract: A carrier containing a core, and a polymer coating containing an inorganic polymer, an organic polymer and an optional further polymer, or polymers.

Abstract: A carrier comprised of a core and thereover a polymer, and which polymer contains dispersed therein a mixture of an inorganic polymer, and an organic metallic polymer.

Abstract: A two-component developer including at least a magnetic toner and a magnetic carrier having magnetic particles coated with carbon black. The magnetic toner adheres to the magnetic carrier due to the magnetic interaction.

Abstract: A carrier for an image developer for electrophotography, including a core material, and a coating layer covering the core material and containing a binder and a powder having an average particle diameter of D &mgr;m and a specific resistance of at least 1012 &OHgr;·cm. The coating layer has a thickness of h &mgr;m. The ratio D/h is greater than 1:1 but less than 5:1.

Abstract: Generation of a drum filming layer is prevented by obtaining a developing agent meeting the relationship y<0.057x+0.1748, where x represents the total addition amount of the additive, which is not smaller than 0.2, and y represents the free component content obtained from the difference in the fluorescence X-ray analytical value between the front surface and the back surface of a pellet of the developing agent, by quantitatively analyzing the free component content of the additive to the developing agent and by using a binder resin satisfying the conditions of 2,000≦number average molecular weight≦5,000, 8,000≦weight average molecular weight≦70,000, and 1.6≦Mw/Mn≦35.

Abstract: Magnetic particles for charging an image-bearing member electrostatically. The charging magnetic particles have magnetic particles, first surface coat layers containing a first surface coating agent and covering the surfaces of the magnetic particles and second surface coat layers containing a second surface coating agent and covering the first surface coat layers. The charging magnetic particles contain magnetic particles for charging which have a maximum chord length of 5 &mgr;m or larger, and the magnetic particles for charging which have a maximum chord length of 5 &mgr;m or larger having a minor-axis length/major-axis length standard deviation of 0.08 or more. Also, a process for producing the charging magnetic particles is disclosed together with a charging member, a process cartridge and an image forming apparatus which make use of the charging magnetic particles.

Abstract: There is disclosed a two-component developing agent for use in an mage formation based on electrophotography, which has high developability even at a high speed printing and good developability in the case of the image formation for a long period of time. The two-component developing agent includes a carrier comprising a magnetic particle and an insulating toner. A surface of the magnetic particle is coated with at least a resin. A mean particle size of the magnetic particle is between 30 and 90 &mgr;m and an aggregation degree of said carrier is between 2 and 15%.

Abstract: A carrier containing a core, a polymer coating or mixtures of polymers thereover, and wherein the coating polymer or mixtures contains a conductive polymer.

Abstract: A carrier for an electrophotographic developer which comprises a carrier core and a resin coat having a conducting agent dispersed therein, the resin coat having an inner layer on the carrier core side and an outer layer coating the inner layer, wherein the inner layer contains 7 to 20% by weight of a conducting agent based on the resinous solid content of the inner layer, the outer layer contains 3 to 15% by weight of a conducting agent based on the resinous solid content of the outer layer, and the conducting agent content of the inner layer is greater than that of the outer layer.

Abstract: Disclosed are a carrier for electrophotography, a method for producing the same carrier, and a developing agent using the same. The carrier includes a carrier core material with magnetism and a high-molecular-weight polyethylene resin that coats the surface of the carrier core material, wherein the surface of the high-molecular-weight polyethylene resin coating the surface of the carrier core material is coated with a resin layer having an ability to control an electric charge and a thickness of 0.01-2 &mgr;m or with a particle layer having an ability to control an electric charge and a thickness of 0.01-2 &mgr;m. The carrier for electrophotography and the developing agent using the same allow free control of its electrification polarity and free adjustment of the amount of electrification, taking advantage of excellent properties of the carrier having a polyolefin-based resin coat.

Abstract: A toner for particular use in devices utilizing hybrid scavengeless development includes toner particles of at least one binder, at least one colorant, and optionally one or more additives, the toner exhibiting a charge per particle diameter (Q/D) of from −0.1 to −1.0 fC/&mgr;m with a variation during development of from 0 to 0.25 fC/&mgr;m and the distribution is substantially unimodal and possesses a peak width of less than 0.5 fC/&mgr;m, and the toner has a triboelectric charge of from −25 to −70 &mgr;C/g with a variation during development of from 0 to 15 &mgr;C/g following triboelectric contact with carrier particles. Use of a toner with such properties in a hybrid scavengeless development apparatus enables images to be achieved with properties similar to that achieved in offset lithography.

Abstract: A carrier with a core and thereover a polymer or mixtures of polymers, and wherein the polymer contains a conductive polymer dispersed therein. Alternatively, the carrier coating can be comprised of a conductive inorganic polymer or a polymer having dispersed therein a conductive inorganic polymer.

Abstract: A developer for a trickle developing method is used in formation of a full color image and is made of a mixture of a toner and a carrier. The toner contains inorganic fine particles as an internal additive and an external additive, a volume average particle diameter D50v of the toner is between 5.0 and 9.0 &mgr;m, a true specific gravity of the carrier is between 3.00 and 4.60, a volume average particle diameter of the carrier is between 15 and 60 &mgr;m, and the ratio of the volume average particle diameter of the carrier to the volume average particle diameter of the toner is between 3.00 and 7.00, and an image forming method using the developer.

Abstract: The present invention relates to a developer for electrostatic image development comprising: a toner for electrostatic image development which comprises a resin and a colorant; and a carrier formed by a carrier core material and a resin layer including a resistance control agent which is formed on the surface of the carrier core material, wherein the resin layer of the carrier has a concentration gradient of the resistance control agent toward the thickness direction of the resin layer, a concentration of the resistance control agent is the highest in the vicinity of the carrier core material, and is gradually lowered toward the surface of the resin layer, and the resistance control agent is present on the surface of the resin layer, as well as relates to an image forming method, wherein it comprises a step of developing an electrostatic image at a developing speed of 20 m/min or higher, by means of employing the developer for electrostatic image development.

Abstract: A developer for developing an electrostatic latent image comprising: toner particles comprising a colorant and a binder resin, said toner particles having a volume-average particle size of 5 to 10 &mgr;m; a first exterior additive comprising hydrophobic titanium oxide powder or hydrophobic aluminum oxide powder; and a second exterior additive comprising a silica powder; said developer satisfying following relationships: S1>S2 400<{square root over ((S12+L +S22+L ))}≦1300. wherein S1 (m2) denotes total specific surface area of the first additive per 1 kg of the toner and S2 (m2) denotes that of the second additive.

Abstract: A carrier for an electrophotographic developer which comprises a carrier core and a resin coat having a conducting agent dispersed therein, the resin coat having an inner layer on the carrier core side and an outer layer coating the inner layer, wherein the inner layer contains 7 to 20% by weight of a conducting agent based on the resinous solid content of the inner layer, the outer layer contains 3 to 15% by weight of a conducting agent based on the resinous solid content of the outer layer, and the conducting agent content of the inner layer is greater than that of the outer layer.

Abstract: Magnetic particles having an average particle size of 10 to 200 &mgr;m, comprising:

Abstract: A carrier and developer material for use in an electrostatographic imaging process comprises a metallic core material which has a diffusion-bonded surface alloy layer on the surface of the particle and an optional polymer layer overcoating the alloy layer. The carrier provides improved conductivity and triboelectric properties when used in an electrophotographic imaging process.

Abstract: A carrier for electrophotographic developer, including a magnetic core material whose surface is coated with a resin, wherein the carrier satisfies the following relationship: 1.0≦C2/C1≦1.3 wherein C1 represents a charge quantity of a developer (1) including the carrier and a first toner after the developer (1) is subjected to a frictional charge treatment once, wherein concentration of the first toner in the developer (1) is 3% by weight; and C2 represents a charge quantity of a developer (2) including the carrier, which has been separated from the developer (1) subjected to the frictional charge treatment, and a second toner when the charge quantity is measured after the developer (2) is subjected to the frictional charge treatment once, wherein concentration of the second toner in the developer (2) is 3% by weight, wherein the first and second toner are the same or different.

Abstract: Electrostatic latent images are developed with a toner in such a configuration that an electrostatic-latent-image-bearing member is disposed to face a developer-bearing member which bears thereon a developer consisting of a magnetic carrier and a toner by relatively moving the developer-bearing member and the electrostatic-latent-image-bearing member at different velocities, with the development being carried out under conditions represented by formula (1): 1 0.

Abstract: An object of the present invention is to provide a developer for electrostatic image development, which exhibits stable charge behavior during printing even when using a polyester resin and does not cause contamination of the inside of the apparatus because of less scattering of the toner, and also facilitates easy maintenance.

Abstract: A carrier comprised of a carrier core, optional polymer coating, and fluorosilanated pigment coating.

Abstract: A carrier comprised of a core and thereover a polymer generated from (1) a polymer containing amine groups, and (2) a second polymer containing sulfonic functional groups.