US5167096A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for texturing a magnetic disc substrate
Assignee: WD Media LLC
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Filing: 1990-02-26
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Granted: 1992-12-01
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Expires: 2010-02-26
Abstract
Abstract Method and apparatus for texturing a substrate for use in a magnetic recording disc. A texturing pad used in the invention has inner and outer coaxial regions, with the outer region being more compressible. When the pad and a substrate are rotated about parallel, offset axes, and pressed against one another in the presence of a particle slurry, the inner, less compressible region of the pad produces a deeper-groove texturing on an inner annular surface region of the disc.
Inventors
- 👤 Atef Eltoukhy
- 👤 Yassin Mehmandoust
- 👤 Shiro Murakami
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:50
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; B; B24; B24B; B24B37/00; B24B37/04; B24B7/00; B24B7/10; B24B7/16; Y; Y10; Y10S; Y10S977/00; Y10S977/70; Y10S977/724; Y10S977/902; Y10S977/932
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
135 words
A method of texturing a magnetic disc substrate, having inner and outer edges, comprising the steps of: rotating the substrate at an angular velocity of between 50-400 rpm about a first axis; and placing the rotating substrate in contact with a texturing pad which rotates about an axis parallel to and offset from the first axis, and which has (a) an inner, relatively incompressible region, and (b) an outer, relatively compressible region, in the presence of a particle slurry between the rotating substrate and pad, by said placing, producing relatively deep textured grooves in an annulus adjacent the inner edge of the substrate surface which is contacted by said inner pad region, and relatively shallow textured grooves over the remaining, outer annular portion of the substrate surface which is contacted by said outer pad region.
Claim 2
Independent Claim
135 words
A method of texturing a magnetic disc substrate, having inner and outer edges, comprising the steps of: rotating the substrate at an angular velocity of between 50-400 rpm about a first axis; and placing the rotating substrate in contact with a texturing pad which rotates about an axis parallel to and offset from the first axis, and which has (a) an inner, relatively incompressible region, and (b) an outer, relatively compressible region, in the presence of a particle slurry between the rotating substrate and pad, by said placing, producing relatively deep textured grooves in an annulus adjacent the inner edge of the substrate surface which is contacted by said inner pad region, and relatively shallow textured grooves over the remaining, outer annular portion of the substrate surface which is contacted by said outer pad region.
Claim 3
Dependent Claim
37 words
The method of claim 1, wherein the pad has a diameter of about 2-3 inches, said inner region has a diameter of about 0.25-1.5 inches, and said outer region has a radial dimension of about 0.25-1.25 inches.
Claim 4
Dependent Claim
26 words
The method of claim 1, wherein the inner and outer regions are separated by an annular spacing having a radial dimension of between about 0.5-1.0 inches.
Claim 5
Dependent Claim
18 words
The method of claim 1, wherein said slurry contains abrasive particles having a size between about 2-10 μ.
Claim 6
Dependent Claim
12 words
The method of claim 1, wherein the substrate is an aluminum substrate.
Claim 7
Dependent Claim
21 words
The method of claim 1, wherein the ratio of pad rotation speed to substrate rotation speed is between 1:10 and 1:30.
Claim 8
Dependent Claim
27 words
The method of claim 6, wherein said inner and outer regions are placed in contact with the substrate for a period of between 15 and 60 seconds.
Claim 9
Dependent Claim
23 words
The method of claim 7, wherein said inner and outer regions are placed against the substrate with a force between about 5-30 lb.
References Cited (Backward Citations)
US3499250A
Cited
US4179852A
Cited
US4557947A
Cited
JPS57144654A
Cited
US4393628A
Cited
US4466218A
Cited
US4525957A
Cited
US4735840A
Cited
US4894133A
Cited
US4835909A
Cited
US4939614A
Cited
JPH0231326A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-12-01 | 1996-06-01 | 1996-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-01 | 2000-06-01 | 2000-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-01 | 2004-06-01 | 2004-12-01 | $7700.00 | Window Closed / Lapsed |