摘要:
In an image forming apparatus, a developing device has a developing sleeve accommodating a magnet roller therein, and a doctor for regulating the amount of developer to be conveyed to a developing position. When the developing sleeve is rotated, the part of the doctor shaved off by the doctor from the sleeve is moved in a developer storing section to a toner replenishing opening formed in a toner storing section. Then, this part of the developer is returned to the doctor along the surface of the sleeve via the toner replenishing opening. The developer consists of a first developer containing a first carrier and deposited in a layer on the surface of the sleeve, and a second developer containing a second carrier different from the first carrier and stored in the developer storing section in such a manner as to contact the first developer deposited on the sleeve. The first carrier has a higher charging ability than the second carrier. The device does not need a toner replenishing mechanism or a toner concentration sensor and has, therefore, a miniature and inexpensive construction. In addition, the device is applicable even to a high-speed image forming apparatus.
摘要:
In a developing device for an image forming apparatus and of the type using a developer consisting of toner and magnetic carrier, a toner hopper has an opening for replenishing toner stored therein. The developer is regulated by a doctor blade to form a thin layer on a developing sleeve. The developer scraped off by the doctor blade is introduced into a developer storing chamber and caused to move toward the opening of the hopper due to its own internal pressure and gravity. The developer from the hopper is returned toward the doctor blade along the surface of the sleeve. The developer on the sleeve and regulated by the doctor blade is conveyed to a developing position where the sleeve faces an image carrier. The toner contained in the developer is a magnetic toner. When the toner concentration of the developer has reached an upper limit, a space or gap exists in the developer storing chamber.
摘要:
A carrier for a dry two-component developer, includes a core material and a silicone-modified acrylic resin layer coated on the surface of the core material, the silicone-modified acrylic resin layer including a silicone-modified acrylic resin, with the ratio of the percentage transmission of infrared spectrum Si--O stretching vibrations (T.sub.Si) of the silicone-modified acrylic resin layer to the percentage transmission of infrared spectrum C.dbd.O stretching vibrations (T.sub.C) thereof, T.sub.Si /T.sub.C, being at least 1.0. The silicone-modified acrylic resin layer can be made from a water-soluble synthetic resin solution containing a silicone macromonomer (A) with a vinyl group being introduced into one terminal thereof, and a vinyl monomer (B) which is copolymerizable with the silicone macromonomer (A), with the molecular weight of the silicone macromonomer (A) of the silicone-modified acrylic resin being in the range of 1,000 to 10,000. Methods of producing such carriers are provided.
摘要:
There is provided a toner which contains at least a binder resin, and filler including a layered inorganic compound, wherein the layered inorganic compound is cleaved to form particles in the toner, and the particles have a breadth of 0.5 nm to 4 nm, and a length of 10 nm to 90 nm.
摘要:
It is an object of the present invention to provide a toner that can sustain favorable transferability and cleaning ability for prolonged periods; prevent photoconductor filming; exhibit no variation in image nonuniformity or external additive immersion induced by developer agitation at the time of use; excels in stability with flowability and charge stability over prolonged periods. Therefore, provided is the toner of which the quantity of aggregate of residual external additives found on the sieve of 635-mesh and 452 cm2 of mesh area, after 0.2 g of the toner on the sieve is blasted with air at a blow pressure of 0.2 MPa from 160 mm above the sieve while being air-suctioned at a suction force of 5 mmHg, and then air-suctioned at a suction force of 20 mmHg, is 4,500 or less and 5 or more.
摘要:
A toner containing toner particles having a core-shell structure containing a binder resin, a colorant and a release agent. The toner particles are prepared by dissolving or dispersing at least one of the binder resin and a precursor thereof in an organic solvent or a polymeric monomer and reacting the resultant in an aqueous medium for reaction, wherein the toner satisfies the following relationship: ΔTm=Tm1−Tm2>10 ° C., wherein Tm1 represents half efflux temperature of the toner and Tm2 represents half efflux temperature of a toner which is prepared by melting and kneading the toner particles and wherein a content of the release agent existing close to the surface portion of the toner particles is from 7 to 30% by volume based on an entire portion close to the surface portion of the toner particles when the content is determined by Fourier Transform Infrared Spectroscopy Attenuated Total Reflection (FTIR-ATR) method.
摘要:
A toner which includes a toner material, wherein the toner satisfies the following formula: 0° C.≦ΔTm≦20° C. where ΔTm represents Tma (° C.)−Tmb (° C.), Tma (° C.) is ½ flown-out temperature of the toner by a capillary type flow tester, and Tmb (° C.) is ½ flown-out temperature of a melt kneaded mixture of the toner by the capillary type flow tester, and wherein Tma is from 130° C. to 200° C.
摘要:
A toner for an image forming apparatus having a volume average diameter of from 2 to 8 μm is manufactured by reacting an aqueous dispersion comprising at least one pigment, a polymer and/or a mixture of monomers to form fine toner particles wherein the amount of fine particles having a diameter of one-half the average number diameter are present in an amount of 20% by number or less, a toner cartridge containing the toner and a method for using the toner.
摘要:
The present invention provides a method for producing a toner including preparing an emulsified dispersion which contains emulsion particles by emulsifying or dispersing an oil phase containing at least a pigment and any one of a binder resin and a binder resin precursor in an aqueous medium, and granulating toner base particles by converging the emulsified dispersion, wherein the Casson yield value of the single oil phase before being emulsified or dispersed in the aqueous medium is 0.5 Pa to 20 Pa; and the temperature Tn of the emulsified dispersion in the preparation of the emulsified dispersion, the temperature Ts of the emulsified dispersion in the granulation of the toner base particles, and the glass transition temperature Tg of the toner base particles satisfy the relation Tn
摘要:
The present invention provides a method for producing a toner including preparing an emulsified dispersion which contains emulsion particles by emulsifying or dispersing an oil phase containing at least a pigment and any one of a binder resin and a binder resin precursor in an aqueous medium, and granulating toner base particles by converging the emulsified dispersion, wherein the Casson yield value of the single oil phase before being emulsified or dispersed in the aqueous medium is 0.5 Pa to 20 Pa; and the temperature Tn of the emulsified dispersion in the preparation of the emulsified dispersion, the temperature Ts of the emulsified dispersion in the granulation of the toner base particles, and the glass transition temperature Tg of the toner base particles satisfy the relation Tn