摘要:
A toner for developing an electrostatic charge image is disclosed, which is formed by adding and mixing an external additive with toner particles having an average particle size of not larger than 9 .mu.m and comprising at least a colorant and a binder resin, wherein the external additive is fine particles having a particle size of 20 to 80 nm. There is also disclosed a process for preparing the toner which comprises adding external additives to the toner particles and mixing them, wherein the addition and mixing of said external additive are carried out under specific conditions.
摘要:
A color toner providing a toner image excellent in brightness, clearness and graininess and a process for producing the same are disclosed, wherein a proportion of dispersed pigment particles having a circle-equivalent diameter of 0.3 .mu.m or greater does not exceed 0.1% of the total number of said dispersed pigment particles. The process comprises kneading a water-containing pigment paste and a binder resin at a temperature of 100.degree. C. or higher under pressure in a heat and pressure kneader to remove a water content to obtain a pigment dispersion, melt-kneading the resulting pigment dispersion together with a binder resin, and grinding the mixture.
摘要:
A surface-treated inorganic fine particle includes an inorganic fine particle, a hydrophobizing agent deposited on the surface of the inorganic fine particle and an amino group-containing coupling agent deposited on the surface of the inorganic fine particle, wherein the hydrophobizing agent and the amino group-containing coupling agent in a ratio of 1/(0.01 to 0.1) by weight are deposited on the surface of the inorganic fine particle by treating the surface of the inorganic fine particle with the hydrophobizing agent and the amino group-containing coupling agent. An electrophotographic developer contains toner particles and the surface-treated inorganic fine particles.
摘要:
An electrophotographic toner composition comprising (A) toner particles with an average particle diameter of 9 .mu.m or less comprising at least a binder resin and a colorant, and (B) an additive, wherein the additive is a fine metal oxide powder surface coated with at least one agent for imparting hydrophobic property selected from the group consisting of the following formulae (1), (2) and (3):R.sub.1 Si(X).sub.3R.sub.1 R.sub.2 Si(X).sub.2R.sub.1 R.sub.2 R.sub.3 Si(X).sub.1wherein R.sub.1 represents a substituted or unsubstituted alkyl group having a molecular weight of 113 or more, R.sub.2 and R.sub.3 each represents hydrogen, an alkyl group or an allyl group, and X represents chlorine, an alkoxy group or an acetoxy group. The toner composition causes no impaction to a carrier and no adhesion of the toner particles to a photoreceptor, and can form stable, sufficient images for a long time.
摘要:
A positively chargeable carrier for developing electrostatic charge images having good surface staining resistance and good environmental reliance of charging is disclosed, which comprises a core material having formed thereon an interlayer having a triboelectrification controlling function and having a nitrogen atom content of from 5 ppm to 75 ppm based on the weight of the core material, and a releasable coated layer formed on the interlayer. A two-component developer using the carrier is also disclosed.
摘要:
A carrier for magnetic brush developer comprising a core material having coated thereon a coated layer containing a graft copolymer comprising a polymer of a nitrogen-containing vinyl monomer or a phosphorus-containing vinyl monomer having a molecular weight of from 1,000 to 5,500 graft-copolymerized thereto a vinyl monomer.
摘要:
A sound deadening member for electrophotographic photoreceptor composed of a molded thermoplastic resin composition obtained by compounding at least 10 parts by weight of a copolymer (A) having a glass transition point of at least 40° C. and being made of from 10 to 90% by weight (meth)acrylic acid ester monomer(s) and not more than 90 parts by weight of a styrene-base resin (B) such that the sum total becomes 100 parts by weight and an electrophotographic photoreceptor having the sound deadening member for electrophotographic photoreceptor in the inside of the conductive substrate.
摘要:
An electrophotographic photoreceptor comprising a conductive substrate having thereon a photosensitive layer is disclosed, said photosensitive layer containing, as a binder resin, a polycarbonate resin comprising at least a repeating unit represented by formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 each represent a hydrogen atom, a halogen atom, an alkyl group having from 1 to 5 carbon atoms, a cycloalkyl group having from 5 to 7 carbon atoms or a phenyl group; and R.sub.5 and R.sub.6 are taken together to form a 5- to 8-membered carbonaceous ring substituted with at least two alkyl groups each having from 1 to 5 carbon atoms. The photoreceptor has high mechanical durability and satisfactory surface smoothness, resistance against reduction in image quality and sensitivity, and stability against environmental change and repeated use.
摘要:
An optically anisotropic pitch, which is suited for manufacturing particularly high compressive strength carbon fibers in a stable fashion, with satisfactory productivity and continuously, and also a method of manufacturing high compressive strength carbon fibers using the optically anisotropic pitch.The optically anisotropic pitch for manufacturing high compressive strength carbon fibers is composed of a benzene soluble component (BS) and a benzene insoluble component (BI) and has a Q value (i.e., weight-average molecular weight divided by number-average molecular weight) of 1.6 or below, a number-average molecular weight ratio of the benzene soluble component to the benzene insoluble component of 2.5 or below, an aromatic carbon fraction factor (fa) of 0.8 or below, a C/H atomic ratio of 1.85 or below and an optically anisotropic phase of 90% or more.
摘要:
Long fiber-reinforced normally solid polyamide resin compositions and molded articles formed thereof include a polyamide base resin, between 5 to 80% by weight of reinforcing fibers having a length of at least 3 mm, and between 0.01 to 3% by weight of a processing aid. The processing aid is a lithium salt of a fatty acid or a metal salt of a fatty acid having 22 to 32 carbon atoms. The compositions are preferably in the form of a generally cylindrical pellet having a length of 3 to 50 mm such that the reinforcing fibers are substantially as long as the pellet in which they are incorporated, and are oriented parallel to one another along the longitudinal axis of the pellet.