Ricoh Company, Ltd.

Toshihiko Takahashi

Masafumi Ohta

Yohta Sakon

Kazukiyo Nagai

Chihaya Adachi

Fumio Kawamura

Teruyuki Ohnuma

Kazuhiko Umemura

Shinichi Kuramoto

Kazuo Tsubuko

Hidemi Uematsu

Tomoyuki Shimada

Mitsuru Hashimoto

Toshiki Nanya

Kimitoshi Yamaguchi

Hiromitsu Kawase

Makoto Ookawara

Tsubuko Kazuo

An electroluminescent device is composed of a negative electrode, a positive electrode, and an organic compound layer which is interposed between the negative electrode and the positive electrode and includes at least one oxadiazole compound with a plurality of aryl oxadiazole structures. Novel oxadiazole compounds for use in the electroluminescent device and a method of producing the oxadiazole compounds are disclosed.

Electroluminescent device comprising oxadiazole compounds luminescent

Method of producing oxadiazole compounds

A fluorine-containing graft copolymer prepared by a step (i) of polymerizing a monomer having formula (I) and an unsaturated carboxylic acid or a monomer having a glycidyl group to obtain a copolymer, ##STR1## wherein R represents --H or --CH.sub.3 group; and A represents --COOC.sub.n H.sub.2n+1 or OC.sub.n H.sub.2n+1, in which n is an integer of 6 to 20; a step (ii) of esterifying the resulting copolymer by using a monomer having a glycidyl group in the case where a constituting monomer of the above copolymer is an unsaturated carboxylic acid, or by using an unsaturated carboxylic acid in the case where a constituting monomer of the above copolymer is a monomer having a glycidyl group; and a step (iii) of graft-polymerizing a monomer comprising at least fluoroalkyl acrylate or fluoroalkyl methacrylate on the above esterified copolymer. In addition, a toner comprising a coloring agent and a resin component which comprises the above-mentioned fluorine-containing graft copolymer is disclosed.

Fluorine-containing graft copolymer and toner using the same

A liquid developer comprises an aliphatic hydrocarbon carrier liquid and a toner dispersed in the carrier liquid, which toner comprises a coloring agent and a resin component, wherein a solid toner component which is obtained by evaporating the liquid developer to dryness has a softening point of 60.degree. C. to 90.degree. C. and flow-initiating point of 110.degree. C. to 160.degree. C.

Liquid developer for image fixing method using heat application rollers

Disclosed herein is an electroluminescent device comprising an anode and a cathode and one or plurality of organic compound layer sandwiched therebetween, at least one of the organic compound layers being composed of an organic compound represented by the general formula (I): ##STR1## (wherein A.sup.1 and A.sup.2 each represents a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group which may be identical or different with each other, Ar represents a substituted or unsubstituted pyrenyl group and n represents 1 or 2).

Electroluminescent device

Disclosed herein is an electroluminescent device having a luminescent layer comprising a luminescent material, which is capable of directly converting the energy of electric field applied thereto into a light energy and capable of providing a large surface-area luminescence.

A negatively chargeable toner for developing latent electrostatic images comprising a coloring agent, a resin component which comprises a homopolymer of a first monomer having formula (I) or a copolymer of the aforementioned first monomer and a second monomer: ##STR1## wherein R.sup.1 represents --H or --CH.sub.3 ; R.sup.2 and R.sup.3 each represent --CN, --COOH or --NO.sub.2 ; R.sup.4 represents --F, --Cl or --Br; and n is an integer of 1 to 10.

Negative toner for developing latent electrostatic images

Growing community of inventors

Numazu, Japan

Toshihiko Takahashi