Patent US4842678A successfully refreshed from Google Patents.
US4842678A
Expired / Lapsed
US
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Polishing cloth and method
Assignee: Asahi Kasei Corp
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Filing: 1988-05-13
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Granted: 1989-06-27
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Expires: 2008-05-13
Abstract
Abstract The present invention relates to a polishing cloth comprising an expanded thermoplastic resin product having a cellular structure, and an expansion ratio of 1.5-fold to 30-fold, with substantially uniform cells having an average cell diameter of 300 μm or less being distributed within the cross-section of the expanded product, and with unexpanded resin phases of 0.5 μm to 45 μm surrounded by three or more cells, wherein the proportion of the unexpanded phases are 0.01% to 70% in terms of area ratio within the expanded product cross-section, which has excellent performance of mirror surface polishing, for example, integrated circuit substrate, disc substrate for information recording, optical lens, optical mirror, etc. The present invention particularly relates to a polishing cloth for precise polishing to a surface roughness of 100 Å or less.
Inventors
- 👤 Shoji Noro
- 👤 Shigemi Mukaiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:56
CPC Classifications
B; B24; B24D; B24D11/00; B24D11/02; A; A47; A47L; A47L13/00; A47L13/10; A47L13/16; A47L13/28
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
82 words
A polishing cloth comprising an expanded thermoplastic resin product having a cellular structure, and an expansion ratio of 1.5-fold to 30-fold, with substantially uniform cells having an average cell diameter of 300 μm or less being distributed within the cross-section of the expanded product, and with unexpanded resin phases of 0.5 μm to 45 μm surrounded by three or more cells, wherein the proportion of the unexpanded phases are 0.01% to 70% in terms of area ratio within the expanded product cross-section.
Claim 2
Dependent Claim
82 words
A polishing cloth comprising an expanded thermoplastic resin product having a cellular structure, and an expansion ratio of 1.5-fold to 30-fold, with substantially uniform cells having an average cell diameter of 300 μm or less being distributed within the cross-section of the expanded product, and with unexpanded resin phases of 0.5 μm to 45 μm surrounded by three or more cells, wherein the proportion of the unexpanded phases are 0.01% to 70% in terms of area ratio within the expanded product cross-section.
Claim 3
Dependent Claim
26 words
The polishing cloth according to claim 1, wherein the expansion ratio is 1.5-fold to 15-fold, and the average cell size is 1 μm to 90 μm.
Claim 4
Dependent Claim
68 words
The polishing cloth according to claim 1, having a cellular structure, and an expansion ratio of 1.5-fold to 15-fold, with an average cell diameter of 1 μm to 90 μm, and with unexpanded resin phases of 0.5 μm to 45 μm surrounded by three or more cells, wherein the proportion of the unexpanded phases are 0.01% to 10% in terms of area ratio within the expanded product cross-section.
Claim 5
Dependent Claim
26 words
The polishing cloth according to claim 1, wherein the cross-sections of the cells are exposed on at least one surface of the expanded thermoplastic resin product.
Claim 6
Dependent Claim
42 words
The polishing cloth according to claim 1, wherein the cross-sections of the cells are exposed on at least one surface of the expanded thermoplastic resin product and the undulations of the outermost surface of the exposed surface are 50 μm or less.
Claim 7
Dependent Claim
53 words
The polishing cloth according to claim 1, wherein at least one surface of the expanded thermoplastic resin product has grooves of a width of 0.1 to 2 mm, a depth of 0.1 to 2 mm formed regularly at intervals of 1 to 50 mm in a shape of lattice, diaper or satin thereon.
Claim 8
Dependent Claim
65 words
The polishing cloth according to claim 1, wherein cross-sections of cells are exposed on at least one surface of the expanded product of the thermoplastic resin and the exposed surface has grooves of a width of 0.1 to 2 mm, a depth of 0.1 to 2 mm formed regularly at intervals of 1 to 50 mm in a lattice, a diaper or a satin pattern.
Claim 9
Dependent Claim
45 words
The polishing cloth according to claims 1, 2, 3, 4, 5, 6 or 7, in which the cells are substantially uniform in size and shape, and wherein there are no abnormally shaped cells or voids comprised within the cross-sections of the expanded thermoplastic resin product.
Claim 10
Dependent Claim
34 words
The polishing cloth according to claim 8, wherein the abnormally shaped cells are cylinder or pear shaped and the voids are macrovoids which are greater by 3-fold or more than the average cell size.
Claim 11
Dependent Claim
30 words
The polishing cloth according to claims 1, 2, 3, 4, 5, 6 or 7, wherein the expanded thermoplastic resin product comprises a polyolefin or a fluoro-resin as the main component.
Claim 12
Dependent Claim
23 words
The polishing cloth according to claim 8, wherein the expanded thermoplastic resin product comprises a polyolefin or a fluoro-resin as the main component.
Claim 13
Dependent Claim
35 words
The poishing cloth according to claims 1, 2, 3, 4, 5, 6 or 7, wherein the expanded thermoplastic resin product comprises a polyolefin or a fluoro-resin as the main component and has a crosslinked structure.
Claim 14
Dependent Claim
28 words
A polishing cloth according to claim 8, wherein the expanded thermoplastic resin product comprises a polyolefin or a fluoro-resin as the main component and has a crosslinked structure.
Claim 15
Dependent Claim
45 words
The polishing method, which comprises mirror polishing a material to be worked by moving the polishing cloth according to any one of claims 1 to 7 relative to the material to be worked while supplying a polishing liquid onto the surface of the polishing cloth.
Claim 16
Dependent Claim
41 words
The polishing method according to claim 14, wherein the polishing liquid is an inorganic or organic liquid having the capability of converting the material to be worked to a compound which will readily dissolve or be liberated through dissolution or reaction.
Claim 17
Dependent Claim
27 words
The polishing method according to claim 14, wherein the surface of the material to be worked is mirror polished to a surface roughness of 100Å or less.
Claim 18
Dependent Claim
114 words
A polishing method, which comprises mirror polishing a material to be worked by moving a polishing cloth comprising an expanded thermoplastic resin product having a cellular structure and an expansion ratio of 1.5-fold to 30-fold, with substantially uniform cells having an average cell diameter of 300 μm or less being distributed within the cross-section of the expanded product, and with unexpanded phases of 0.5 μm to 45 μm surrounded by three or more cells, wherein the proportion of the unexpanded phases are 0.01% to 70% in terms of area ratio within the expanded product cross-section, relative to the material to be worked while supplying a polishing liquid onto the surface of the polishing cloth.
Claim 19
Dependent Claim
114 words
A polishing method, which comprises mirror polishing a material to be worked by moving a polishing cloth comprising an expanded thermoplastic resin product having a cellular structure and an expansion ratio of 1.5-fold to 30-fold, with substantially uniform cells having an average cell diameter of 300 μm or less being distributed within the cross-section of the expanded product, and with unexpanded phases of 0.5 μm to 45 μm surrounded by three or more cells, wherein the proportion of the unexpanded phases are 0.01% to 70% in terms of area ratio within the expanded product cross-section, relative to the material to be worked while supplying a polishing liquid onto the surface of the polishing cloth.
References Cited (Backward Citations)
US4600469A
Cited
US4645561A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-26 | 1992-12-26 | 1993-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-26 | 1996-12-26 | 1997-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-26 | 2000-12-26 | 2001-06-27 | $7700.00 | Window Closed / Lapsed |