Idemitsu Kosan Company, Limited

Dow Corning Toray Silicone Company Limited

Shuji Sakamoto

Hironobu Morishita

Hideyuki Miyamoto

Tomohiro Nagao

Kazuyoshi Shigematsu

Takaaki Hikosaka

Takashi Nakagawa

Chishio Hosokawa

Yoshitsugu Morita

Tadashi Okawa

Haruhiko Furukawa

Masami Kanamaru

Hiroshi Ueki

Tadashi Kusumoto

Ryuko Manzoji

Shigenori Shirouzu

Yasuaki Horikawa

Toshiyasu Suzuki

Polycarbonate, and molding and electrophotographic photoreceptor

Polycarbonate resin, crosslinked polycarbonate resin and

A polyester polymer comprising repeating units (I), or repeating units (I) and (II), and having a reduced viscosity (.eta. sp/c) of 0.2 to 10.0 dl/g, measured at 20.degree. C. as a 0.5 g/dl solution dissolved in methylene chloride is prepared by allowing a dihydric phenol (III), or dihydric phenols (III) and (IV), to react with a carbonate precursor or a dibasic acid. An electrophotographic photoreceptor which comprises an electroconductive substrate and a photosensitive layer disposed on the electroconductive substrate and containing the polyester polymer as a charge transporting material or a binder resin. ##STR1## wherein, W is --O-- or single bond, X is a divalent group which is derived from a dihydric phenol containing a hydrazine structure, each of R.sup.25 and R.sup.26 is a halogen atom, an alkyl group, a cycloalkyl group or an aryl group, each of m and n is an integer of 0 to 4, Y is single bond, --O--, --S--, --SO--, --SO.sub.2 --, --CR.sup.27 R.sup.28 --, a 1,1-cycloalkylene group or an .alpha.,.omega.-alkylene group.

Polyester polymer, production thereof and electrophotographic

Polycarbonate, method of preparing the same and electrophotographic

Organic electroluminescence device

Electrophotographic photoreceptors which are free of the whitening (gelation) of coating solutions during production thereof and maintain high mechanical strength, high surface hardness and excellent electrophotographic properties for a long period, are provided by using, as binder-resins in photosensitive layers, polycarbonate resins comprising the repeating unit represented by the following formula (I): ##STR1## and the repeating unit represented by the following formula (II): ##STR2## the molar ratio of the repeating unit (I) to the total of the repeating units (I) and (II) being from 0.01 to 0.5, and the polycarbonate resin having a reduced viscosity of from 0.2 to 3.0 dl/g as measured in methylene chloride at a concentration of 0.5 g/dl at 20.degree. C.

Electrophotographic photoreceptor containing polycarbonate resin as

Dihydric phenol suitable for the preparation of polycarbonates are represented by the following formula: ##STR1##

Dihydric phenols

An electrophotographic photoreceptor comprising an electroconductive layer and a photosensitive layer disposed on one surface of the electroconductive substrate, the photosensitive layer containing a specific polycarbonate or polycarbonate copolymer used as a binder-resin, has such advantageous characteristics that it can be produced by using an application method without accompanying with whitening (gelation) of the coating liquid used for forming the photosensitive layer nor inviting occurrence of solvent-cracks in the formed photosensitive layer. In addition, it excels in mechanical strength and the characteristics required in electrophotography which can be maintained even if it is repeatedly used over long periods.

Electrophotographic photoreceptor

A resin material for optical instruments comprising a polycarbonate having the repeating units represented by the following general formula: ##STR1## wherein X represents ##STR2## has an extremely small birefringence particularly to oblique-incident lights.

Optical disk substrate comprising aromatic polycarbonate

A polycarbonate polymer containing repeating units represented by the following general formula ##STR1## wherein: X is selected from single bond, ##STR2## wherein: R.sup.1 and R.sup.2 are each independently selected from hydrogen atom; alkyl radical of 1 to 6 carbon atoms; cycloalkyl radical of 5 to 6 carbon atoms; ##STR3## wherein p is an integer having a value of from 0 to 3; phenyl radicals substituted at para position by a substituent selected from alkoxy radicals of 1 to 5 carbon atoms, phenoxy radicals, or halogen radicals; or p-biphenylyl radical, --CH.sub.2).sub.q wherein q is an integer having a value of from 2 to 10; or ##STR4## wherein r is an integer having a value of from 4 to 8, and having a reduced viscosity [.eta.sp/c] of at least 0.2 dl/g as measured in methylene chloride at a concentration of 0.5 g/dl at 20.degree. C. Such polycarbonates exhibit excellent optical properties such as high birefringence, and are useful as materials for optical devices. Also, a process for preparing the polycarbonates and novel dihydric phenols which can be used as materials for the polycarbonates are disclosed.

Polycarbonate containing compound from bis(3-phenyl-4-hydroxyphenyl)

Growing community of inventors

Sodegaura, Japan

Shuji Sakamoto