Fujitsu Corporation

Hirofumi Okuyama

Toshiaki Narusawa

Seiji Okada

Teruo Yagishita

Kiyohide Muramatsu

Kasumi Ikegami

Norio Sawatari

Akihiro Mochizuki

Isao Watanabe

Kazumasa Saito

A developing material for electrostatic images comprising (a) carrier particles comprising iron beads coated with a layer of butadiene polymer resin in which Fe.sub.3 O.sub.4 powder is dispersed, the volume ratio of the polymer resin to Fe.sub.3 O.sub.4 is from 1:2 to 4:1, and the butadiene polymer is cured by heating with an organic peroxide of from 0.5 to 5.0 parts by weight, based on the weight of the butadiene polymer, which comprises a homopolymer containing 1,2-polybutadiene units, or a homopolymer or copolymer of cyclized 1,4-cis-polybutadiene and (b) from 1% to 6% by weight, based on the weight of the carrier particles, of toner particles which comprise a bis-phenol A-epichlorohydrin type resin, carbon powder, a nigrosine dye, and either a styrene-n-butyl acrylate copolymer or a montan wax.

Developer comprising a carrier coated with Fe.sub.3 O.sub.4 dispersed in

A storage type liquid crystal composition in which a nematic-cholesteric mesophase transition is utilized and the anisotropy of the dielectric constant is positive and an X-Y dot-matrix-type storage-type liquid-crystal display element comprising the composition. The present liquid crystal composition has low driving voltage and long memory effect. This composition comprises a cyclohexane-type liquid crystal, an azoxy-type liquid crystal, and a compensated cholesteric liquid crystal and/or cholesteryl oleate.

Storage-type liquid crystal composition

A process for preparing a developer for electrostatic images comprising: (1) immersing carrier beads in an organic solution of a resin material comprising a 1,2-butadiene or cyclized cis-1,4-butadiene homopolymer, or a mixture of at least one of the homopolymers and a styrene butadiene copolymer; evaporating the organic solvent of the solution, drying the immersed beads, and curing the resin material by a rotary drying method, to form a resin coating on the carrier beads; (2) blending toner materials at a temperature sufficient to form a toner mass, the toner materials comprising: (a) a binder resin, (b) a colorant, and (c) a charge controlling agent; and (3) pulverizing the blended toner mass to form toner particles and mixing the obtained toner particles with the coated carrier in a predetermined ratio of the total surface area of the carrier to the total projection area of the toner particles.

Process for preparing electrostatic developer

A holographic recording material comprising a polymer containing vinylcarbazole rings, a cyclic cis-.alpha.-dicarbonyl compound capable of forming a radical by light irradiation and a dye as a photosensitizer or a spectral sensitizer. A hologram can be obtained by exposing the holographic recording material to an interference pattern of a radiation to form a holographic interference pattern, subjecting the material to a swelling treatment in a first medium, and then subjecting the material to a contraction treatment in a second medium.

Holographic recording material and process for producing holograms

A developer material for electrostatic images comprising a mixture of (1) a coated carrier and (2) a toner. (1) The carrier consists of core beads coated with a coating resin comprising a butadiene homopolymer of a molecular weight of from 10,000 to 100,000, for the butadiene homopolymer is 1,2-polybutadiene and/or cyclized cis-1,4-polybutadiene or a mixture of at least one of these homopolymers and a styrene/butadiene copolymer of a molecular weight of from 10,000 to 100,000, the mixture containing from 7.5 to 100% by weight, based on the weight of the mixture, of butadiene in polymerized form. (2) The toner comprises, based on the weight of the toner, (A) from 85 to 95% by weight of a binder resin comprising, based on the weight of the binder resin, from 50 to 100% by weight of an epoxy resin of a molecular weight of from 900 to 8,000 and from 0 to 50% by weight of a styrene/alkyl methacrylate copolymer, the alkyl group having from 1 to 4 carbon atoms, of a molecular weight of from 10,000 to 100,000; (B) a colorant comprising, based on the weight of the toner, from 0 to 10% by weight of fine carbon and from 0.5 to 8% by weight of a nigrosine dye, and; (C) from 0 to 8% by weight of a charge controlling agent, based on the weight of the toner, comprising a quaternary ammonium alkyl sulfonate, the alkyl group having from 4 to 20 carbon atoms, or di-(polyhydroxyethoxy ethyl) octadecyl amine, or a polyamine. The ratio of the total surface area of the coated carrier to the total projection area of the toner particles is in the range of from 1:0.5 to 1:2.0.

Developer materials for electrostatic images

A process for preparing a developer material for electrostatic images comprising a mixture of (1) a coated carrier and (2) a toner by a rotary drying method.

Process for preparing developer materials for electrostatic images

A photosensitive material for electrophotography is provided which has a very high sensitivity to rays having a wavelength included in the oscillation wavelength region of a laser printer, especially a semiconductor laser printer, and which also has a high charge potential. This photosensitive material comprises a phthalocyanine pigment, poly-N-vinylcarbazole, and an organic resin in which said phthalocyanine pigment and poly-N-vinylcarbazole are dispersed, wherein the weight ratio of phthalocyanine pigment to poly-N-vinylcarbazole is in the range of from 1.2 to 12 and the content of the organic resin is 35% to 70% by weight based on the total amount of the photosensitive material.

Organic photosensitive material for electrophotography

A photosensitive material for electrophotography having an improved photosensitivity is provided, which comprises copper phthalocyanine as a photoconductor, 2,5-bis(4'-diethylaminophenyl)-1,3,4-oxadiazole as a charge transport material and a binder resin in which said photoconductor and charge transport material are dispersed. The content of the binder resin is 50 to 70% by weight based on the total amount of the photosensitive material and the weight ratio of copper phthalocyanine to 2,5-bis(4'-diethylaminophenyl)-1,3,4-oxadiazole is in the range of from 2.5 to 6.5.

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Sagamihara, Japan

Hirofumi Okuyama