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Patent US4595715A successfully refreshed from Google Patents.
US4595715A
Expired / Lapsed
US
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Oriented polyester film containing calcium carbonate and kaolinite
Assignee: Nippon Magphane KK
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Filing: 1984-09-07
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Granted: 1986-06-17
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Expires: 2004-09-07
Abstract
Abstract An oriented polyester film comprising ethylene terephthalate as the major repeating unit, which comprises particles of kaolinite and calcium carbonate uniformly dispersed therein, said kaolinite and said calcium carbonate having each an average particle size of 0.05 to 0.8 micron and being contained in such amounts as satisfying the following equations: 70</=DxA</=1000 (I) 1000</=A+B</=10000 (II) 0.1</=B/A</=25 (III) wherein D is an average particle size (micron) of calcium carbonate, A is a content (ppm) of calcium carbonate and B is a content (ppm) of kaolinite, said oriented polyester film being excellent in flatness, slipperiness, abrasion resistance, etc. with a small number of coarse particles.
Inventors
- 👤 Katsuaki Kuze
- 👤 Yujiro Matsuyama
- 👤 Kozo Maeda
- 👤 Takeshi Ota
- 👤 Masahiro Kobayashi
- 👤 Tsuyoshi Hongo
- 👤 Osamu Makimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:30
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08K3/24; C08K3/26; Y; Y10; Y10T; Y10T428/00; Y10T428/26; Y10T428/268; Y10T428/31504; Y10T428/31786
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
98 words
An oriented polyester film comprising ethylene terephthalate as the major repeating unit, which comprises particles of kaolinite and calcium carbonate uniformly dispersed therein, said kaolinite and said calcium carbonate having each an average particle size of 0.05 to 0.8 micron and being contained in such amounts as satisfying the following relationships: 70≦D×A≦1000 (I) 1000≦A+B≦10000 (II) 0.1≦B/A≦25 (III) wherein D is an average particle size (micron) of calcium carbonate, A is a content (ppm) of calcium carbonate and B is a content (ppm) of kaolinite; said film including not more than 3 coarse particles per 4.8 mm 2 .
Claim 2
Dependent Claim
98 words
An oriented polyester film comprising ethylene terephthalate as the major repeating unit, which comprises particles of kaolinite and calcium carbonate uniformly dispersed therein, said kaolinite and said calcium carbonate having each an average particle size of 0.05 to 0.8 micron and being contained in such amounts as satisfying the following relationships: 70≦D×A≦1000 (I) 1000≦A+B≦10000 (II) 0.1≦B/A≦25 (III) wherein D is an average particle size (micron) of calcium carbonate, A is a content (ppm) of calcium carbonate and B is a content (ppm) of kaolinite; said film including not more than 3 coarse particles per 4.8 mm 2 .
Claim 3
Dependent Claim
21 words
The film according to claim 1, wherein the average particle size of kaolinite is not smaller than that of calcium carbonate.
Claim 4
Dependent Claim
22 words
The film according to claim 1, wherein kaolinite and calcium carbonate have each an average particle size of 0.1 to 0.5 micron.
Claim 5
Dependent Claim
22 words
The film according to claim 3, wherein kaolinite and calcium carbonate have each an average particle size of 0.2 to 0.5 microns.
Claim 6
Dependent Claim
26 words
The film according to claim 1, wherein the average particle size of calcium carbonate and the content of calcium carbonate satisfy the following relationship: 100≦D×A≦800 (I')
Claim 7
Dependent Claim
23 words
The film according to claim 1, wherein the content of calcium carbonate and the content of kaolinite satisfy the following relationship: 2000≦A+B≦6000 (II')
Claim 8
Dependent Claim
23 words
The film according to claim 1, wherein the content of calcium carbonate and the content of kaolinite satisfy the following relationship: 0.2≦B/A≦20 (III')
Claim 9
Dependent Claim
12 words
The film according to claim 1, which is a biaxially stretched film.
Claim 10
Dependent Claim
17 words
The film according to claim 1, which is used as a base film for magnetic recording tape.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-16 | 1989-12-16 | 1990-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-16 | 1993-12-16 | 1994-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-16 | 1997-12-16 | 1998-06-17 | $7700.00 | Window Closed / Lapsed |