Patent US5026510A successfully refreshed from Google Patents.
US5026510A
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US
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Mold for cast molding substrate having preformat with information pits and method of using same
Assignee: Canon Inc
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Filing: 1989-03-10
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Granted: 1991-06-25
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Expires: 2009-03-10
Abstract
Abstract A cast mold and process for casting a substrate for an information recording medium has an uneven preformat pattern formed on the mold surface. The uneven preformat features a pattern corresponding to tracking grooves and information pits, each information pit portion has a size with a length b in the direction parallel to the pattern of the tracking groove of 2 to 15 μm and a width a in the direction perpendicular thereto of 1 to 6 μm and a height c of 300 to 3500 Å. The pit pattern has a pitch which is 1.8-fold or more of pit length b.
Inventors
- 👤 Masataka Yashima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:29
CPC Classifications
B; B29; B29D; B29D17/00; B29D17/005; B29C; B29C33/00; B29C33/42; B29C33/424; G; G11; G11B; G11B7/00; G11B7/24; G11B7/2407; G11B7/24085; B29C39/00; B29L; B29L2017/00; B29L2017/001; B29L2017/003; B29L2017/005; G11B7/26; G11B7/263; Y; Y10; Y10S; Y10S425/00; Y10S425/81
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
162 words
A method for preparing a substrate for an information recording medium comprising the steps of: selecting a casting mold having a mold surface for casting said substrate, said casting mold having an uneven preformat pattern, said mold surface comprising an uneven preformat pattern formed thereon, said uneven preformat pattern having tracking groove portions corresponding to tracking grooves and information pit portions corresponding to information pits, wherein each information pit portion has a size with a length b of 2 to 15 μm in the direction parallel to the pattern of the tracking groove, a width a of 1 to 6 μm in the direction perpendicular thereto and a height c of 300 to 3500 Å, said pit pattern having a pitch in the direction parallel to the pattern of the tracking grooves, said pitch being at least 1.8 times said pit length b; pouring a composition comprising monomer, prepolymer or a mixture thereof into said mold; and polymerizing and curing said composition.
Claim 2
Independent Claim
162 words
A method for preparing a substrate for an information recording medium comprising the steps of: selecting a casting mold having a mold surface for casting said substrate, said casting mold having an uneven preformat pattern, said mold surface comprising an uneven preformat pattern formed thereon, said uneven preformat pattern having tracking groove portions corresponding to tracking grooves and information pit portions corresponding to information pits, wherein each information pit portion has a size with a length b of 2 to 15 μm in the direction parallel to the pattern of the tracking groove, a width a of 1 to 6 μm in the direction perpendicular thereto and a height c of 300 to 3500 Å, said pit pattern having a pitch in the direction parallel to the pattern of the tracking grooves, said pitch being at least 1.8 times said pit length b; pouring a composition comprising monomer, prepolymer or a mixture thereof into said mold; and polymerizing and curing said composition.
Claim 3
Dependent Claim
41 words
A method for preparing a substrate according to claim 1, wherein b is from 3 to 12 μm, a is from 2 to 4 μm, c is from 1000 to 3000 Å, and the pitch is at least 2 times b.
Claim 4
Independent Claim
154 words
A method for preparing an information recording medium comprising the steps: selecting a cast mold having a mold surface for a substrate for information recording medium having an uneven preformat pattern, said mold surface comprising an uneven preformat pattern formed thereon, said uneven preformat pattern having tracking groove portions corresponding to tracking grooves and information pit portions corresponding to information pits, wherein each information pit portion has a size with a length b of 2 to 15 μm in the direction parallel to the pattern of the tracking groove, a width a of 1 to 6 μm in the direction perpendicular thereto and a height c of 300 to 3500 Å, said pit pattern having a pitch in the direction parallel to the pattern of the tracking grooves, said pitch being at least 1.8 times said pit length b; casting a substrate using said cast mold; and forming a recording layer on said substrate.
Claim 5
Independent Claim
154 words
A method for preparing an information recording medium comprising the steps: selecting a cast mold having a mold surface for a substrate for information recording medium having an uneven preformat pattern, said mold surface comprising an uneven preformat pattern formed thereon, said uneven preformat pattern having tracking groove portions corresponding to tracking grooves and information pit portions corresponding to information pits, wherein each information pit portion has a size with a length b of 2 to 15 μm in the direction parallel to the pattern of the tracking groove, a width a of 1 to 6 μm in the direction perpendicular thereto and a height c of 300 to 3500 Å, said pit pattern having a pitch in the direction parallel to the pattern of the tracking grooves, said pitch being at least 1.8 times said pit length b; casting a substrate using said cast mold; and forming a recording layer on said substrate.
Claim 6
Dependent Claim
43 words
A method for preparing an information recording medium according to claim 3, wherein b is from 3 to 12 μm, a is from 2 to 4 μm, c is from 1000 to 3000 Å, and the pitch is at least 2 times b.
Claim 7
Dependent Claim
20 words
A method for preparing an information recording medium according to claim 3, wherein said recording layer is formed by coating.
Claim 8
Dependent Claim
23 words
A method for preparing an information recording medium according to claim 5, wherein the material for said recording layer is an organic dye.
Claim 9
Dependent Claim
21 words
A method for preparing an information recording medium according to claim 3, wherein said information recording medium is an optical card.
Claim 10
Dependent Claim
127 words
A mold having a mold surface for casting a substrate for information recording medium having an uneven preformat pattern, said mold surface comprising an uneven preformat pattern formed thereon, said uneven preformat pattern having tracking groove portions corresponding to tracking grooves and information pit portions corresponding to information pits, wherein each information pit portion has a size with a length b of 2 to 15 μm in the direction parallel to the pattern of the tracking groove, a width a of 1 to 6 μm in the direction perpendicular thereto and a height c of 300 to 3500 Å, said pit pattern having a pitch in the direction parallel to the pattern of the tracking grooves, said pitch being at least 1.8 times said pit length b.
Claim 11
Dependent Claim
127 words
A mold having a mold surface for casting a substrate for information recording medium having an uneven preformat pattern, said mold surface comprising an uneven preformat pattern formed thereon, said uneven preformat pattern having tracking groove portions corresponding to tracking grooves and information pit portions corresponding to information pits, wherein each information pit portion has a size with a length b of 2 to 15 μm in the direction parallel to the pattern of the tracking groove, a width a of 1 to 6 μm in the direction perpendicular thereto and a height c of 300 to 3500 Å, said pit pattern having a pitch in the direction parallel to the pattern of the tracking grooves, said pitch being at least 1.8 times said pit length b.
Claim 12
Dependent Claim
43 words
A mold for casting according to claim 8, wherein b is from 3 to 12 μm, a is from 2 to 4 μm, c is from 1000 to 3000 Å, and said pit pattern has a pitch of at least 2 times b.
References Cited (Backward Citations)
US3882214A
Cited
US3875024A
Cited
US4387068A
Cited
US4430401A
Cited
JPS6192450A
Cited
US4900902A
Cited
US4743409A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-06-24 | 1994-12-24 | 1995-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-24 | 1998-12-24 | 1999-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-24 | 2002-12-24 | 2003-06-25 | $7700.00 | Window Closed / Lapsed |