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Optical recording medium

Assignee: Olympus Optical Co Ltd
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Filing: 1989-11-13
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Granted: 1991-05-28
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Expires: 2009-11-13
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Abstract

Abstract An optical recording medium such as an optical disk, which is capable of reversibly repeating a recording/erasing cycle. This optical recording medium comprises a transparent substrate and recording layer formed on the substrate. This recording layer comprise a liquid crystalline high polymer having side chains and a dyestuff having a recording-light absorbing property. The side chain may preferably comprises mesogen group, a monocyclic or polycyclic compound such as phenyl, benzyl, naphthyl or anthryl group, and alkyl or aryl group having 1 to 18 carbon atoms.

Inventors

  • 👤 Toshiyuki Kanno
  • 👤 Naoyuki Ueno
  • 👤 Seiji Kondo
  • 👤 Yasuji Nagata
  • 👤 Jun Kanehira
  • 👤 Hideshi Takahashi
  • 👤 Yoshiko Uematsu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 02:51
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/242; G11B7/244; G11B7/25; C; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/08; C09K19/10; C09K19/24; C09K19/26; C09K19/34; C09K19/3441; C09K19/3483; C09K19/38; C09K19/3833; C09K19/40; G11B7/004; G11B7/0055; G11B7/00555; C09K19/12; C09K2019/121; C09K2019/122; C09K19/20; C09K19/2007; C09K2019/2035; Y; Y10; Y10S; Y10S430/00; Y10S430/146

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 174 words
An optical recording medium which has no electrode layer and comprises: a transparent substrate; and a recording layer, formed on said transparent substrate, and comprising at least one type of a liquid crystal polymer compound having side chain groups provided with molecular rotation power or power of changing a state such as an agglomeration or an arrangement, and a dye compound having absorbing power for recording light, wherein upon radiation of recording light on said recording layer, affinity and association between the polymer compound and the dye compound are induced or dissociation and separation of the dye compound from the polymer compound are induced due to differences in chemical and physical characteristics such as a glass transition point and a melting point between the side chain groups of said polymer compound and said dye compound thereby to enclose said dye compound between regularly arranged side chain groups of said polymer compound and to change optical characteristics of the recording medium, thereby accumulating/erasing optical information and reading the optical information by utilizing the optical changes.
Claim 2
Dependent Claim 174 words
An optical recording medium which has no electrode layer and comprises: a transparent substrate; and a recording layer, formed on said transparent substrate, and comprising at least one type of a liquid crystal polymer compound having side chain groups provided with molecular rotation power or power of changing a state such as an agglomeration or an arrangement, and a dye compound having absorbing power for recording light, wherein upon radiation of recording light on said recording layer, affinity and association between the polymer compound and the dye compound are induced or dissociation and separation of the dye compound from the polymer compound are induced due to differences in chemical and physical characteristics such as a glass transition point and a melting point between the side chain groups of said polymer compound and said dye compound thereby to enclose said dye compound between regularly arranged side chain groups of said polymer compound and to change optical characteristics of the recording medium, thereby accumulating/erasing optical information and reading the optical information by utilizing the optical changes.
Claim 3
Dependent Claim 16 words
A medium according to claim 1, wherein said polymer compound is a single or composite compound.
Claim 4
Dependent Claim 31 words
A medium according to claim 1, wherein said dye compound is a single or composite compound and said dye compound has an absorption peak in a wavelength range of recording light.
Claim 5
Dependent Claim 63 words
A medium according to claim 1, wherein said liquid crystal polymer compound is a side chain type liquid crystal polymer represented by following formula (I), which has a mesogen group at side chain portions Y and Y' thereof via a flexible spacer, and has ##STR121## n=2 to 9, at backbone portions X and X': ##STR122## wherein 30≦l+m≦5,000 and l/m=10 to 100/90 to 0.
Claim 6
Dependent Claim 23 words
A medium according to claim 4, wherein said liquid crystal polymer exhibits liquid crystallinity at a temperature from 40° C. to 350° C.
Claim 7
Dependent Claim 22 words
A medium according to claim 4, wherein said recording layer consists essentially of a liquid crystal polymer and a laser-light absorbing dye.
Claim 8
Dependent Claim 17 words
A medium according to claim 4, wherein no auxiliary electric field is required for recording or erasure.
Claim 9
Dependent Claim 29 words
A medium according to claim 1, wherein said liquid crystal polymer compound is a polypeptide-based polymer liquid crystal having a liquid crystal functional group at a side chain thereof.
Claim 10
Dependent Claim 16 words
A medium according to claim 1, wherein a reflecting film is formed on said recording layer.
Claim 11
Dependent Claim 55 words
A medium according to claim 1, wherein a side chain group having a structure in which a spatial structure is obtained between side chain groups so that suitable miscibility with said dye compound is obtained or said dye compound can easily enter between said side chain groups is introduced in said liquid crystal polymer compound
Claim 12
Dependent Claim 40 words
A medium according to claim 10, wherein said side chain group having a structure for forming a spatial structure is a monocyclic or polycyclic compound and is introduced in an amount of not less than 0.01 per side chain group.
Claim 13
Dependent Claim 53 words
A medium according to claim 1, wherein said side chain group having a structure for forming a spatial structure is an aliphatic compound having 1 to 18 carbon atoms or an aryl having up to 18 carbon atoms and is introduced in an amount of not less than 0.01 per side chain group.
Claim 14
Dependent Claim 159 words
A medium according to claim 1, wherein said dye compound is a cyanine-based dyestuff represented by the following formula ##STR123## wherein ψ, L, X, Y and Z are as follows: ##STR124## L is --CH═CH CH═wherein n is an integer of 1 to 3, ##STR125## wherein A is Cl, F or Br, ##STR126## wherein A' is Cl, F or Br or ##STR127## X is I⊖, ClO4⊖, BSF⊖, Br⊖ or BF4⊖; Y is C n .sbsb.1 H 2n .sbsb.1 +1, n 1 =1 to 18, C n .sbsb.2 H 2n .sbsb.2 OC m H 2m+1 , n 2 ,m=1 to 18, (CH 2 ) n .sbsb.3 R, n 3 =zero to 18, ##STR128## R=SO 3 Na, SO 3 H or C n .sbsb.4 H 2n .sbsb.4 --1 C m .sbsb.1 H 2m .sbsb.1, n 4 m 1 =1 to 18; Z is --X (halogen), --R (alkyl), --ROH, --RCOH, --RCOOH, --ROR', --RCOR', --RCOOR', ##STR129## ##STR130## --CH═CH--CN, --OCF 3 or --OSF 3 .
Claim 15
Dependent Claim 42 words
A medium according to claim 1, wherein said dye compound is a merocyanine-based dyestuff represented by the following formula ##STR131## wherein, R═H, CH 3 , X (halogen) or OC m H 2m+1 , m=1 to 3; A═S or Se; n═1 to 6
Claim 16
Dependent Claim 22 words
A medium according to claim 1, wherein said dye compound is an arylazo-based dyestuff represented by the following formula X--N═N--Y--N═N--Z wherein, ##STR132##
Claim 17
Dependent Claim 30 words
A medium according to claim 11, wherein said side chain having a structure for forming a spatial structure is selected from the group consisting of phenyl, benzyl, naphthyl and anthryl.
Claim 18
Dependent Claim 19 words
A medium according to claim 12, wherein the aliphatic compound is an alkyl having 1 to 18 carbon atoms.

References Cited (Backward Citations)

US4752820A Cited
JPS60179294A Cited
US4702945A Cited
US4857427A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-05-27 1994-11-26 1995-05-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-05-27 1998-11-26 1999-05-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-05-27 2002-11-26 2003-05-28 $7700.00 Window Closed / Lapsed

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