摘要:
An image forming method is disclosed in which a contact charging means is brought into contact with a latent image bearing member to electrostatically charge the latent image bearing member on which electrostatic latent images are formed and developed with a one component type or two component type developer to form toner images, using a developing assembly provided with a developing container and a developer carrying member. The one component developer is comprised of toner particles. The two component type developer is comprised of toner particles and a magnetic carrier. The toner particles of the one component type and two component type developers contains fine particles as an external additive.The latent image bearing member has a surface layer having a volume resistivity A of from 10.sup.8 to 10.sup.15 .OMEGA..multidot.cm; the contact charging means comprises an assembly for electrostatically charging the latent image bearing member by applying a voltage to a charging member having a volume resistivity B of from 10.sup.4 to 10.sup.9 .OMEGA..multidot.cm; the toner has, as an external additive, fine particles having a volume resistivity C of from 10.sup.7 to 10.sup.11 .OMEGA..multidot.cm; the magnetic carrier has a volume resistivity D1 of from 10.sup.9 to 10.sup.15 .OMEGA..multidot.cm; and the developer carrying member has a surface layer having a volume resistivity D2 of from 10.sup.9 to 10.sup.15 .OMEGA..multidot.cm. The resistivities A, B, C, D1 and D2 stasisfy the following conditions: B
摘要:
A carrier for electrophotography has carrier particles. The carrier has a 50% average particle diameter (D.sub.50) of from 15 .mu.m to 45 .mu.m and contains from 1% to 20% of carrier particles with a size smaller than 22 .mu.m, not more than 3% of carrier particles with a size smaller than 16 .mu.m, from 2% to 15% of carrier particles with a size of 62 .mu.m or larger, and not more than 2% of carrier particles with a size of 88 .mu.m or larger. The carrier has a specific surface area S.sub.1 as measured by an air-permeability method and a specific surface area S.sub.2 as calculated by the following expression: S.sub.2 =(6/.rho..multidot.D.sub.50).times.10.sup.4 wherein .rho. is a specific gravity of carrier; satisfying the following condition: 1.2 .ltoreq.S.sub.1 /S.sub.2 .ltoreq.2.0.
摘要:
A carrier for electrophotography has carrier particles. The carrier has a 50% average particle diameter (D.sub.50) of from 15 .mu.m to 45 .mu.m and contains from 1% to 20% of carrier particles with a size smaller than 22 .mu.m, not more than 3% of carrier particles with a size smaller than 16 .mu.m, from 2% to 15% of carrier particles with a size of 62 .mu.m or larger, and not more than 2% of carrier particles with a size of 88 .mu.m or larger. The carrier has a specific surface area S.sub.1 as measured by an air-permeability method and a specific surface area S.sub.2 as calculated by the following expression:S.sub.2 =(6/.rho..D.sub.50).times.10.sup.4wherein .rho. is a specific gravity of carrier; satisfying the following condition:1.2.ltoreq.S.sub.1 /S.sub.2 .ltoreq.2.0.
摘要:
An electrophotographic apparatus includes an electrophotographic photosensitive member, and (i) a charger, (ii) an imagewise exposure device, (iii) a developing device and (iv) a transfer device, disposed in this order opposite to the photosensitive member. The charger includes a charging member including magnetic particles disposed in contact with the photosensitive member so as to charge the photosensitive member based on a voltage received thereby. The magnetic particles are surface-coated with a coupling agent having a linear alkyl group having a least 6 carbon atoms. The developing device also functions to recover residual toner remaining on the photosensitive member processing by the transfer device and the charger. Because of the coating with such a specific coupling agent, the charging magnetic particles can exhibit good triboelectric changeability for the transfer residual toner for a long period.
摘要:
A toner is disclosed which has toner particles and an external additive. The toner has (a) in circularity distribution of particles measured with a flow type particle image analyzer, an average circularity of from 0.920 to 0.995, containing particles with a circularity of less than 0.950 in an amount of from 2% by number to 40% by number; and (b) a weight-average particle diameter of from 2.0 .mu.m to 9.0 .mu.m as measured by Coulter method. The external additive has, on the toner particles, at least (i) an inorganic fine powder (A) present in the state of primary particles or secondary particles and having an average particle length of from 10 m.mu.m to 400 m.mu.m and a shape factor SF-1 of from 100 to 130 and (ii) a non-spherical inorganic fine powder (B) formed by coalescence of a plurality of particles and having a shape factor SF-1 of greater than 150. Also, a two-component developer and an image forming method, using the toner, are disclosed.
摘要:
A two-component type developer has a negatively chargeable toner having toner particles and an external additive and a magnetic-fine-particle-dispersed resin carrier. The magnetic-fine-particle-dispersed resin carrier has composite particles containing at least inorganic compound particles and a binder resin. The inorganic compound particles have been surface-treated with a lipophilic-treating agent having at least one type of functional group (A) selected from the group consisting of an epoxy group, an amino group, a mercapto group, an organic acid group, an ester group, a ketone group, an alkyl halide group and an aldehyde group, or a mixture of the agent. The composite particles have been surface-coated with at least one type of coupling agent having at least one type of functional group (B) different from the functional group (A) the lipophilic-treating agent. The functional group (B) the coupling agent has being a functional group or groups selected from the group consisting of an epoxy group, an amino group and a mercapto group. The negatively chargeable toner has a weight-average particle diameter of from 3 &mgr;m to 9 &mgr;m.
摘要:
In the image forming machine of the invention, a two-component type developer has a spherical magnetic powder dispersion type carrier, which has a weight average particle diameter of from 15 to 60 .mu.m. The external additive is present in the form of particles on the toner particle, and comprises inorganic oxide fine particles A having a shape factor SF-1 of from 100 to 130, and non-spherical inorganic oxide fine particles B, having a shape factor SF-1 larger than 150 and particles B having been obtained by combining a plurality of component particles.
摘要:
A carrier for electrophotography has carrier particles. Each carrier particle has a carrier core and a silicone resin coat layer that covers the carrier core. The carrier particle has silicon atoms and carrier atoms on its surface in the ratio that satisfies the condition of Si/C=0.1 to 2.0 as the number of atoms present on the carrier particle surface as measured by X-ray photoelectron spectroscopy, and from 0.1% by number to 5% by number of metal atoms are present on the carrier particle surface. Additionally, there is a two-component developer for developing electrostatic images which consists of a toner and the carrier. An image forming method in which the two-component developer having the toner and the carrier is transported to a developing zone which is defined by a latent image carried on a latent image bearing member to develop the latent image. A voltage is applied to the developer to direct the toner from the latent image bearing member to a member carrying the developer. A second voltage directs the toner from the developer toward the latent image and a third voltage developer the latent image using the toner of the two-component developer.
摘要:
An image forming method is conducted by forming a toner image on a latent image bearing member containing an organic photoconductive material. The latent image bearing member includes a photosensitive layer containing an organic photoconductive material and a protective layer which contains fluorine-containing resin particles in an amount from 5% by weight to 40% by weight. The toner contains toner particles and external additives. The external additives include titanium oxide particles having a weight average particle diameter from 0.01 .mu.m to 0.2 .mu.m having been subjected to hydrophobic treatment, organic resin particles having a weight average particle diameter from 0.02 .mu.m to 0.5 .mu.m, and inorganic compound particles having a weight average particle diameter from 0.5 .mu.m to 2.5 m. The inorganic compound particles may be specific titanates, oxides or carbonate. The external additives are added in an amount satisfying the relationship: (A):(B)=2:1 to 10:1 (A):(C)=1:1 to 5:1 The toner contains toner particles having a particle diameter from 2 .mu.m to 5 .mu.m in an amount from 15% by number to 40% by number. The toner image is transferred to a transfer medium and the latent image bearing member is then cleaned.
摘要:
The present invention provides a toner for developing an electrostatic image, comprising toner particles and external additives, wherein;said external additives comprise (A) titanium oxide particles having a weight average particle diameter of from 0.01 .mu.m to 0.2 .mu.m, having been subjected to hydrophobic treatment, (B) organic resin particles having a weight average particle diameter of from 0.02 .mu.m to 0.5 .mu.m and (C) an inorganic compound having a weight average particle diameter of from 0.5 .mu.m to 2.5 .mu.m; said external additives being added in an amount satisfying the relationship:(A):(B)=2:1 to 10:1(A):(C)=1:1 to 5:1; andsaid toner contains toner particles having a particle diameter of from 2 .mu.m to 5 .mu.m in an amount of from 15% by number to 40% by number.