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US4870429A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical foam-spacer disk assembly

Assignee: SUNITOMO CHEMICAL COMPANY Ltd 15 KITAHAMA-5-CHOME HIGASHI-KU OSAKA JAPAN A CORP OF JAPAN
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Filing: 1987-03-02
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Granted: 1989-09-26
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Expires: 2007-03-02
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Abstract

Abstract An optical disk is provided which comprises two sheets of substrates; or two sheets of substrate and a reinforcing plate or a reinforcing rim; or one sheet of substrate and a reinforcing plate; which are bonded to form an integrated body having a spacer interposed therebetween, said spacer being made of elastomeric foam having a specific gravity of not more than 1.5 and an expansion ratio of not less than 1.5 as the material of the said spacer. This optical disk has a high adaptability of the drive and exhibits a high reliability, i.e. excellent vibration restricting performance, thereby being possible to provide a stable and highly accurate information processing.

Inventors

  • 👤 Tsutomu Fujita
  • 👤 Yoshiaki Togawa
  • 👤 Seimei Yasui
  • 👤 Toshitsugu Kikuchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 11:28
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10S430/00; Y10S430/146

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 78 words
An optical disk comprising an assembly of two sheets of substrate which are bonded to form an integrated body having a spacer interposed therebetween, said spacer being made of an elastomeric foam material having a specific gravity of not more than 1.5 and an expansion ratio of 1.5 to 15, the elastomer of the foam material having a glass transition temperature of not more than 30° C and a reversible elastic region of strain of 1 to 2000%.
Claim 2
Dependent Claim 78 words
An optical disk comprising an assembly of two sheets of substrate which are bonded to form an integrated body having a spacer interposed therebetween, said spacer being made of an elastomeric foam material having a specific gravity of not more than 1.5 and an expansion ratio of 1.5 to 15, the elastomer of the foam material having a glass transition temperature of not more than 30° C and a reversible elastic region of strain of 1 to 2000%.
Claim 3
Dependent Claim 32 words
An optical disk according to claim 1, wherein said elastomer has a glass transition temperature of not more than 0° C and a reversible elastic region of strain of 100 to 1000%.
Claim 4
Dependent Claim 23 words
An optical disk according to claim 2, wherein said spacers are disposed at the inner and outer periphery parts of the optical disk.
Claim 5
Dependent Claim 20 words
An optical disk according to claim 1, wherein said elastomeric foam material has an expansion ratio of 3 to 10.
Claim 6
Dependent Claim 23 words
An optical disk according to claim 4, wherein said spacers are disposed at the inner and outer periphery parts of the optical disk.
Claim 7
Dependent Claim 23 words
An optical disk according to claim 1, wherein said spacers are disposed at the inner and outer periphery parts of the optical disk.
Claim 8
Dependent Claim 14 words
An optical disk of claim 1, wherein the assembly further comprises a reinforcing plate.
Claim 9
Dependent Claim 14 words
An optical disk of claim 1, wherein the assembly further comprises a reinforcing rim.
Claim 10
Dependent Claim 82 words
An optical disk comprising an assembly of one sheet of substrate and a reinforcing plate, which are bonded to form an integrated body having a spacer interposed therebetween, said spacer being made of an elastomeric foam material having a specific gravity of not more than 1.5 and an expansion ratio of 1.5 to 15, the elastomer of the foam material having a glass transition temperature of not more than 30° C and a reversible elastic region of strain of 1 to 2000%.
Claim 11
Dependent Claim 82 words
An optical disk comprising an assembly of one sheet of substrate and a reinforcing plate, which are bonded to form an integrated body having a spacer interposed therebetween, said spacer being made of an elastomeric foam material having a specific gravity of not more than 1.5 and an expansion ratio of 1.5 to 15, the elastomer of the foam material having a glass transition temperature of not more than 30° C and a reversible elastic region of strain of 1 to 2000%.
Claim 12
Dependent Claim 32 words
An optical disk according to claim 9, wherein said elastomer has a glass transition temperature of not more than 0° C and a reversible elastic region of strain of 100 to 1,000%.
Claim 13
Dependent Claim 20 words
An optical disk according to claim 9, wherein said elastomeric foam material has an expansion ratio of 3 to 10.
Claim 14
Dependent Claim 23 words
An optical disk according to claim 9, wherein said spacers are disposed at the inner and outer periphery parts of the optical disk.
Claim 15
Dependent Claim 23 words
An optical disk according to claim 10, wherein said spacers are disposed at the inner and outer periphery parts of the optical spacer.
Claim 16
Dependent Claim 23 words
An optical disk according to claim 11, wherein said spacers are disposed at the inner and outer periphery parts of the optical disks.

References Cited (Backward Citations)

US4074282A Cited
DE3337527A1 Cited
JPS5971146A Cited
US4555716A Cited
EP0109245A2 Cited
US4564850A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-09-25 1993-03-27 1993-09-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-09-25 1997-03-27 1997-09-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-09-25 2001-03-27 2001-09-26 $7700.00 Window Closed / Lapsed

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