Patent US640023A successfully refreshed from Google Patents.
Patent US4821050A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4821050A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical information recording medium

Assignee: Fujifilm Holdings Corp
•
Filing: 1987-07-17
•
Granted: 1989-04-11
•
Expires: 2007-07-17
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An optical information recording medium of two disc substrates, which are adhered directly or through a convex portion formed on at least one of the substrates or a spacer provided between the substrates by an adhesive layer, and a recording layer which is capable of recording and/or reading information by laser beam and which is provided on a surface of at least one of the substrates facing the other substrate, wherein the adhesive layer is formed by an ultraviolet-curing epoxy adhesive composition comprising a light-initiator which produces a cationic polymerization initiator upon irradiation with ultraviolet rays and an epoxy compound having two or more epoxy groups per molecule.

Inventors

  • 👤 Masao Yabe
  • 👤 Yonosuke Takahashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 06:41
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/256; G11B7/253; G11B7/2531; G11B7/2533; G11B7/2534; G11B7/257; G11B7/2572; G11B7/2575; Y; Y10; Y10S; Y10S430/00; Y10S430/146

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 106 words
An optical information recording medium comprising two disc substrates, which are adhered directly or through a convex portion formed on at least one of the substrates or a spacer provided between the substrates by an adhesive layer, and a recording layer which is capable of recording and/or reading information by laser beam and which is provided on a surface of at least one of the substrates facing the other substrate, wherein the adhesive layer comprises an ultraviolet-curing epoxy adhesive composition comprising a light-initiator which produces a cationic polymerization initiator upon irradiation with ultraviolet rays and an epoxy compound having two or more epoxy groups per molecule.
Claim 2
Dependent Claim 106 words
An optical information recording medium comprising two disc substrates, which are adhered directly or through a convex portion formed on at least one of the substrates or a spacer provided between the substrates by an adhesive layer, and a recording layer which is capable of recording and/or reading information by laser beam and which is provided on a surface of at least one of the substrates facing the other substrate, wherein the adhesive layer comprises an ultraviolet-curing epoxy adhesive composition comprising a light-initiator which produces a cationic polymerization initiator upon irradiation with ultraviolet rays and an epoxy compound having two or more epoxy groups per molecule.
Claim 3
Dependent Claim 17 words
An optical information recording medium as in claim 1, wherein said light initiator is a diazonium salt.
Claim 4
Dependent Claim 17 words
An optical information recording medium as in claim 1, wherein said light initiator is an onium salt.
Claim 5
Dependent Claim 17 words
An optical information recording medium as in claim 1, wherein said light initiator is a thiopyrylium salt.
Claim 6
Dependent Claim 19 words
An optical information recording medium as in claim 1, wherein said light initiator is a hydroxybenzophenone methane sulfonate ester.
Claim 7
Dependent Claim 17 words
An optical information recording medium as in claim 1, wherein said light initiator is a diaryliodosyl salt.
Claim 8
Dependent Claim 19 words
An optical information recording medium as in claim 1, wherein said light initiator is an organic metal complex cation.
Claim 9
Dependent Claim 32 words
An optical information recording medium as in claim 1, wherein said spacers are made of a material having the same thermal expansion coefficient and humidity expansion coefficient as that of the substrates.
Claim 10
Dependent Claim 22 words
An optical information recording medium as in claim 1, wherein said recording layer has a thickness of from 150 to 1,000 Å.
Claim 11
Dependent Claim 26 words
An optical information recording medium as in claim 1, wherein a subbing layer is present between the inner surface of the substrate and the recording layer.
Claim 12
Dependent Claim 25 words
An optical information recording medium as in claim 10, wherein the subbing layer has a thickness within the range of from 0.01 to 10 μm.
Claim 13
Dependent Claim 17 words
An optical information recording medium as in claim 1, wherein said adhesive composition further comprises a sensitizer.
Claim 14
Dependent Claim 22 words
An optical information recording medium as in claim 12, wherein said sensitizer has an absorption wavelength of from 300 to 450 nm.
Claim 15
Dependent Claim 31 words
An optical information recording medium as in claim 1, wherein the weight mixing ratio of the light initiator to the epoxy compound is within the range of from 0.0001/1 to 0.1/1.
Claim 16
Dependent Claim 25 words
An optical information recording medium as in claim 12, wherein said sensitizer is selected from the group consisting of anthracene, benzophenone, pyrene, thioxanthone, and phenothiazine.

References Cited (Backward Citations)

US4434429A Cited
US4499477A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-04-10 1992-10-10 1993-04-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-04-10 1996-10-10 1997-04-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-04-10 2000-10-10 2001-04-11 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag