US4590119A
Expired / Lapsed
US
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Polyester film and magnetic recording medium therefrom
Assignee: Toray Industries Inc
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Filing: 1984-06-20
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Granted: 1986-05-20
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Expires: 2004-06-20
Abstract
Abstract An oriented polyester film is provided according to the present invention which contains, per 100 parts by weight of a polyester, (A) 0.005-2 parts by weight of fine particles having average size of 0.05-3 μm, and (B) 0.005-2 parts by weight of at least one compound selected from the group consisting of high aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof. Herein also disclosed is a composite polyester film which comprises a resin layer of copolyester or copolyester ether containing an ester-forming alkali metal salt of sulfonic acid compound, the layer being laminated on at least one side of the oriented polyester film as a substrate. The present invention further provides a magnetic recording medium comprising the oriented polyester film or the composite polyester film as a base. The novel films of the present invention have a surface satisfying three properties: flatness, slipperiness and adhesion, which are considered unable to be attained with a conventional polyester film. Furthermore, a magnetic recording medium having good electromagnetic conversion and running properties can be obtained from the films in the invention.
Inventors
- 👤 Ken-Ichi Kawakami
- 👤 Toshiya Yoshii
- 👤 Masaru Suzuki
- 👤 Hotsuma Okasaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:22
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/739; G11B5/73923; G11B5/73927; G11B5/73935; G11B5/73931; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/24975; Y10T428/25; Y10T428/254; Y10T428/256; Y10T428/257; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265; Y10T428/31504; Y10T428/3154; Y10T428/31544; Y10T428/31786
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
78 words
A magnetic recording medium comprising: (1) an oriented polyester film containing, per 100 parts by weight of a polyester, (A) 0.005-1 part by weight of fine particles having an average size of 0.05-3 μm, and (B) 0.005-0.5 parts by weight of at least one compound selected from the group consisting of higher aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof; and (2) a magnetic layer laminated on at least one side of the oriented polyester film.
Claim 2
Dependent Claim
78 words
A magnetic recording medium comprising: (1) an oriented polyester film containing, per 100 parts by weight of a polyester, (A) 0.005-1 part by weight of fine particles having an average size of 0.05-3 μm, and (B) 0.005-0.5 parts by weight of at least one compound selected from the group consisting of higher aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof; and (2) a magnetic layer laminated on at least one side of the oriented polyester film.
Claim 3
Dependent Claim
32 words
The magnetic recording medium of claim 1, in which the oriented polyester film has a surface roughness (Ra) of 0.001-0.025 μm and a coefficient of static friction (μ s ) of 0.3-1.0.
Claim 4
Dependent Claim
33 words
The magnetic recording medium of claim, in which the oriented polyester film has a surface roughness (R a ) of 0.001-0.010 μm and a coefficient of static friction (μ s ) of 0.4-0.9.
Claim 5
Dependent Claim
15 words
The magnetic recording medium of claim 1, in which the polyester consists of polyethylene terephthalate.
Claim 6
Dependent Claim
16 words
The magnetic recording medium of claim 1, in which the polyester consists of polyethylene α,β-bis(2-chlorophenoxy) ethane-4,4'-dicarboxylate.
Claim 7
Dependent Claim
33 words
The magnetic recording medium of claim 1, in which the fine particles consist of oxides or inorganic salts which contain an element of the Group II, III or IV in the periodic table.
Claim 8
Dependent Claim
16 words
The magnetic recording medium of claim 1, in which the fine particles consist of fluorinated polymers.
Claim 9
Dependent Claim
22 words
The magnetic recording medium of claim 1, in which the average size of thefine particles is in the range of 0.1-2 μm.
Claim 10
Dependent Claim
21 words
The magnetic recording medium of claim 1, which the oriented polyester film contains 0.01-0.5 parts by weight of the fine particles.
Claim 11
Dependent Claim
18 words
The magnetic recording medium of claim 1, in which the higher aliphatic monocarboxylic acid has 20-32 carbon atoms.
Claim 12
Dependent Claim
49 words
The magnetic recording medium of claim 10, in which the higher aliphatic acid component consists of at least one compound selected from the group consisting of melissic acid, cerotic acid, erucic acid, montanic acid, ceryl montanate myricyl cerotate, ceryl cerotate, carnauba wax, insect wax, behenic acid and stearyl behenate.
Claim 13
Dependent Claim
34 words
The magnetic recording medium of claim 1, in which the oriented polyester film contains more than 0.1 parts by weight and not more than 0.5 parts by weight of the higher aliphatic acid component.
Claim 14
Dependent Claim
55 words
The magnetic recording medium of claim 1, in which the oriented polyester film is biaxially oriented, the birefringence in plane thereof being in the range of 0-0.1, the sum of in-plane refractive indices being in the range of 3.2-3.42 and the ratio of refractive indices in the thickness direction being in the range of 0.935-0.980.
Claim 15
Dependent Claim
19 words
The magnetic recording medium of claim 1, in which the oriented polyester film has a thickness of 4-75 μm.
Claim 16
Dependent Claim
18 words
The magnetic recording medium of claim 1, in which the magnetic layer has a thickness of 0.01-1.0 μm.
Claim 17
Dependent Claim
40 words
The magnetic recording medium of claim 1, in which the magnetic layer comprises γ-Fe 2 O 3 , γ-Fe 2 O 3 , doped with Co, CrO 2 , Fe, Co, Ni or an alloy thereof or a mixture thereof.
Claim 18
Dependent Claim
29 words
The magnetic recording medium of claim 15, in which the magnetic layer is formed by a method selected from the group consisting of vacuum deposition, sputtering and ion plating.
Claim 19
Dependent Claim
18 words
The magnetic recording medium of claim 1, which is a magnetic recording tape or a magnetic recording disk.
Claim 20
Dependent Claim
11 words
The magnetic recording medium of claim 1, which is a videotape.
Claim 21
Dependent Claim
12 words
The magnetic recording medium of claim 1, which is a floppy disk.
Claim 22
Dependent Claim
11 words
The magnetic recording medium of claim 1, which is an audiotape.
Claim 23
Dependent Claim
14 words
The magnetic recording medium of claim 1, which is a tape for a computer.
Claim 24
Dependent Claim
57 words
An oriented polyester film containing, per 100 parts by weight of polyethylene α, β-bis(2-chlorophenoxy) ethane-4,4'-dicarboxylate, (A) 0.005-2 parts by weight of fine particles having average size of 0.05-3 μm; and (B) 0.005-2 parts by weight of at least one compound selected from the group consisting of high aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof.
Claim 25
Dependent Claim
57 words
An oriented polyester film containing, per 100 parts by weight of polyethylene α, β-bis(2-chlorophenoxy) ethane-4,4'-dicarboxylate, (A) 0.005-2 parts by weight of fine particles having average size of 0.05-3 μm; and (B) 0.005-2 parts by weight of at least one compound selected from the group consisting of high aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof.
Claim 26
Dependent Claim
57 words
An oriented polyester film containing, per 100 parts by weight of a polyester, (A) 0.005-2 parts by weight of fluorinated polymer fine particles having average size of 0.05-3 μm, and (B) 0.005-2 parts by weight of at least one compound selected from the group consisting of high aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof.
Claim 27
Dependent Claim
57 words
An oriented polyester film containing, per 100 parts by weight of a polyester, (A) 0.005-2 parts by weight of fluorinated polymer fine particles having average size of 0.05-3 μm, and (B) 0.005-2 parts by weight of at least one compound selected from the group consisting of high aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof.
Claim 28
Dependent Claim
95 words
A composite polyester film comprising; (1) an oriented polyester film containing, per 100 parts by weight of a polyester, (A) 0.005-2 parts by weight of fine particles having average size of 0.05-3 μm, and (B) 0.005-2 parts by weight of at least one compound selected from the group consisting of high aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof, and (2) a resin layer of copolyester or copolyester ether containing an ester-forming alkali metal salt of sulfonic acid compound, the layer being laminated on at least one side of the oriented polyester film.
Claim 29
Dependent Claim
95 words
A composite polyester film comprising; (1) an oriented polyester film containing, per 100 parts by weight of a polyester, (A) 0.005-2 parts by weight of fine particles having average size of 0.05-3 μm, and (B) 0.005-2 parts by weight of at least one compound selected from the group consisting of high aliphatic monocarboxylic acids having 10-33 carbon atoms and esters thereof, and (2) a resin layer of copolyester or copolyester ether containing an ester-forming alkali metal salt of sulfonic acid compound, the layer being laminated on at least one side of the oriented polyester film.
Claim 30
Dependent Claim
24 words
The composite polyester film of claim 25, in which the ester-forming alkali metal salt of sulfonic acid compound is sodium sulfoisophthalate or sodium sulfoterephthalate.
Claim 31
Dependent Claim
18 words
The composite polyester film of claim 25, in which the resin layer has a thickness of 0.005-1.0 μm.
Claim 32
Dependent Claim
23 words
The composite polyester film of claim 25, in which the surface roughness of the resin layer is in the range of 0.003-0.020 μm.
Claim 33
Dependent Claim
21 words
A magnetic recording medium comprising a magnetic layer formed on at least one side of the composite film of claim 25.
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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) | 1989-05-19 | 1989-11-18 | 1990-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-19 | 1993-11-18 | 1994-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-19 | 1997-11-18 | 1998-05-20 | $7700.00 | Window Closed / Lapsed |