Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Noboru Sasa is active.

Publication


Featured researches published by Noboru Sasa.


Journal of Molecular Structure | 1998

Synthesis, structural and conformational analysis and chemical properties of phthalocyaninatometal complexes

Noboru Sasa; Kenji Okada; Kazuo Nakamura; Sachiko Okada

Abstract Syntheses of the phthalocyaninatometal complexes were performed and the crystal and molecular structures were determined by single-crystal X-ray diffraction analysis. The general formulas of these Pc dye compounds are —[Si(Pc)OSiR 1 2 R 2 SiR 1 2 O] n — and Si(Pc)(OSiR 1 R 2 R 3 ) 2 : —[Si(Pc)OSi(CH 3 ) 2 (CH 2 ) 7 Si(CH 3 ) 2 O] n — ( 1 ), Si(Pc)[OSi(C 6 H 13 ) 3 ] 2 ( 2 ) Si(Pc)[OSiC 8 H 17 (CH 3 ) 2 ] 2 ( 3 ) and Si(Pc)[OSiCH 3 C 12 H 25 CH 3 ] 2 ( 4 ). These Pc dye derivatives were prepared by refluxing a mixture of Si(Pc)(OH) 2 and SiR 1 R 2 R 3 Cl in pyridine, followed by cooling the mixture slowly and then drying the resulting precipitates. For 1–3 , the Pc skeleton and the oxo-bridged substituentes are coplanar. The dihedral angle between the mean planes of the Pc skeleton and two single-atom Si me [Si me OSi pc OSi me ] is nearly at right angles. The Si pc O bonds are shorter than the Si pc N bonds and the Si me O bonds are shorter than the Si pc O bonds. For 1 , the Pc microcyclic rings are related by a center of symmetry at the center of the O 1 Si 1 O 2 bonds. The chemical formula of a mononer is C 43 H 42 N 8 O 2 Si 3 (C 25 H 28 N 5 O 2 Si 3 in crystallographic symmetry) and the polymer is built up by the addition polymerization of the monomers. The polymer chain is constructed at the siloxy group along the a axis. Two hexyl groups of two siloxy side groups for 2 have the same direction, but one hexyl extends in the opposite direction. For 3 , two methyl groups and one octyl group extend in the opposite direction. We applied Pc dyes 2–4 , mixed with a polymer for the control of the aggregation state to CD-R and DVD-R recording systems. The aggregation state of the recording layer is controlled by choosing the set of axial substituents R 1 –R 3 . The interactions of Pc dyes with polymers are dependant upon the length of axial substituents. We achieved the best writing contrast and the highest stability with the mixed PC dye 4 . The conformation of axial substituents is very important for the ability of the dye aggregation and the capability to control the aggregation state.


Archive | 2003

Optical recording method and apparatus for an optical storage medium

Noboru Sasa; Tatsuya Tomura; Soh Noguchi; Tsutomu Satoh; Yasunobu Ueno; Yasuhiro Higashi


Archive | 2001

Optical recording medium and optical recording and reading method using the same

Soh Noguchi; Tsutomu Satoh; Tatsuya Tomura; Noboru Sasa; Yasunobu Ueno; Yasuhiro Higashi; Ikuo Shimizu; Hiroshi Toyoda; Motoharu Kinugasa; Shiho Yamada; Masanori Ikuta; Kenji Mutoh


Archive | 2005

Write-once-read-many optical recording media and process for recording and reproducing information on the media

Noboru Sasa; Yoshitaka Hayashi; Hirotaka Komoda; Atsuyuki Watada; Kawori Tanaka; Toshishige Fujii; Hisamitsu Kamezaki


Archive | 1998

Optical recording medium and recording and/or reproduction method using the same

Yasunobu Ueno; Tsutomu Sato; Tatsuya Tomura; Noboru Sasa; Yasuhiro Higashi


Archive | 2006

Sputtering target and manufacturing method therefor, and optical recording medium and manufacturing method therefor

Yoshitaka Hayashi; Noboru Sasa; Toshishige Fujii; Masayuki Fujiwara


Archive | 2004

Write once type optical recording medium and its recording and reproduction method

Toshishige Fujii; Yoshitaka Hayashi; Hisamitsu Kamezaki; Hirotoshi Komoda; Kaori Otaka; Noboru Sasa; Atsuyuki Watada; 久光 亀崎; 篤行 和多田; かをり 大高; 嘉隆 林; 弘敏 薦田


Archive | 2004

WRITE ONCE OPTICAL RECORDING MEDIUM AND METHOD FOR REGENERATING ITS RECORDING

Toshishige Fujii; Yoshitaka Hayashi; Hisamitsu Kamezaki; Kokei Komoda; Kaori Otaka; Noboru Sasa; Atsuyuki Watada; 久光 亀崎; 篤行 和多田; かをり 大高; 嘉隆 林; 弘敬 薦田


Archive | 2006

Write-onece-read-many optical recording medium, sputtering target and the production method thereof

Yoshitaka Hayashi; Toshishige Fujii; Noboru Sasa; Masayuki Fujiwara


Archive | 2001

Optical recording medium having short wobble period length

Tatsuya Tomura; Tsutomu Satoh; Noboru Sasa; Soh Noguchi; Yasunobu Ueno; Yasuhiro Higashi

Researchain Logo
Decentralizing Knowledge