EP0229670A2
Expired / Lapsed
EP
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Biaxially oriented aromatic polyester film
Assignee: Teijin Ltd
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Filing: 1987-01-15
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Granted: —
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Expires: 2007-01-15
Abstract
Abstract A biaxially oriented film formed from an intimate mixture comprising (I) an aromatic polyester, (II) 0.005 to 1.0% by weight, based on the aromatic polyester, of fine particles of a silicone resin having (a) a composition represented by the following formula (A)wherein R represents a hydrocarbon group having 1 to 7 carbon atoms, and x is a number of from 1 to 1.2, (b) a volume shape factor (f), represented by the following formula (B), of more than 0.4 but not exceeding π/6wherein V is the average volume /µm<sup>3</sup>) of the particles and D is the average maximum particle diameter (µm) of the particle, and (c) an average particle diameter of 0.3 to 4 µm. The film optionally contains (III) 0.005 to 1% by weight, based on the aromatic polyester, of inert fine particles having an average particle diameter of 0.01 to 1 m but being smaller than the average particle diameter of the silicone resin particles. The film is useful for a base film of a magnetic recording medium.
Inventors
- 👤 Hisashi Hamano
- 👤 Kinji Hasegawa
- 👤 Yoshihiro Noumi
- 👤 Hideo Katoh
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 23:51
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; B; B29; B29C; B29C48/00; B29C48/022; B29C55/00; B29C55/005; C08L; C08L67/00; C08L67/02; C08L83/00; G; G11; G11B; G11B5/00; G11B5/62; B29C48/03; B29C48/04; B29C48/07; B29C48/08; B29K; B29K2067/00; B29K2105/00; B29K2105/06; B29K2105/16; C08J2367/00; C08J2367/02; C08L2203/00; C08L2203/16; C08L2205/00; C08L2205/14; C08L2205/18; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31786
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
121 words
A biaxially oriented film formed from an intimate mixture comprising (I) an aromatic polyester, and (II) 0.005 to 1.0% by weight, based on the aromatic polyester, of fine particles of a silicone resin having (a) a composition represented by the following formula (A) wherein R represents a hydrocarbon group having 1 to 7 carbon atoms, and x is a number of from 1 to 1.2, (b) a volume shape factor (f), represented by the following formula (B), of more than 0.4 but not exceeding x/ 6 wherein V is the average volume (µm 3 ) of the particles and D is the average maximum particle diameter (vm) of the particle, and (c) an average particle diameter of 0.01 to 4 µm.
Claim 2
Dependent Claim
121 words
A biaxially oriented film formed from an intimate mixture comprising (I) an aromatic polyester, and (II) 0.005 to 1.0% by weight, based on the aromatic polyester, of fine particles of a silicone resin having (a) a composition represented by the following formula (A) wherein R represents a hydrocarbon group having 1 to 7 carbon atoms, and x is a number of from 1 to 1.2, (b) a volume shape factor (f), represented by the following formula (B), of more than 0.4 but not exceeding x/ 6 wherein V is the average volume (µm 3 ) of the particles and D is the average maximum particle diameter (vm) of the particle, and (c) an average particle diameter of 0.01 to 4 µm.
Claim 3
Dependent Claim
30 words
The film of claim 1 wherein the aromatic polyester is derived from an aromatic dicarboxylic acid as a main acid component and an aliphatic glycol as a main glycol component.
Claim 4
Dependent Claim
30 words
The film of claim 1 wherein in formula (A), R represents a linear or branched alkyl group having 1 to 7 carbon atoms, a phenyl group, or a tolyl group.
Claim 5
Dependent Claim
18 words
The film of claim 1 wherein in formula (A), x is a number of from 1 to 1.1.
Claim 6
Dependent Claim
22 words
The film of claim 1 wherein the volume shape factor f of the silicone resin particles is between 0.44 and π/6 .
Claim 7
Dependent Claim
21 words
The film of claim 1 wherein the average particle diameter of the silicone resin particles is between 0.05 and 3 µm.
Claim 8
Dependent Claim
24 words
The film of claim 1 wherein the amount of the silicone resin particles is 0.01 to 0.5% by weight based on the aromatic polyester.
Claim 9
Dependent Claim
64 words
The film of claim 1 wherein the silicone resin particles have a particle size distribution ratio (y), defined by the following equation (C) of 1 to 1.4, wherein D 25 is the particle diameter (µm) of the silicone resin particles when their cumulative weight is 25%, and D 75 is the particle diameter of the silicone resin particles when their cumulative weight is 75%.
Claim 10
Dependent Claim
36 words
The film of claim 1 wherein when the film surface is ion-etched and then observed under an electron microscope, the peripheral surfaces of the silicone resin particles are substantially in contact with the aromatic polyester substrate.
Claim 11
Dependent Claim
160 words
A biaxially oriented film formed from an intimate mixture comprising (I) an aromatic polyester, (II) 0.005 to 1.0% by weight, based on the aromatic polyester, of fine particles of a silicone resin having (a) a composition represented by the following formula (A) wherein R represents a hydrocarbon group having 1 to 7 carbon atoms, and x is a number of from 1 to 1.2, (b) a volume shape factor (f), represented by the following formula (B), of more than 0.4 but not exceeding x/6 wherein V is the average volume ( u m 3 ) of the particles and D is the average maximum particle diameter (µm) of the particle, and (c) an average particle diameter of 0.3 to 4 µm, and (III) 0.005 to 1% by weight, based on the aromatic polyester, of inert fine particles having an average particle diameter of 0.01 to 1 µm but being smaller than the average particle diameter of the silicone resin particles.
Claim 12
Dependent Claim
160 words
A biaxially oriented film formed from an intimate mixture comprising (I) an aromatic polyester, (II) 0.005 to 1.0% by weight, based on the aromatic polyester, of fine particles of a silicone resin having (a) a composition represented by the following formula (A) wherein R represents a hydrocarbon group having 1 to 7 carbon atoms, and x is a number of from 1 to 1.2, (b) a volume shape factor (f), represented by the following formula (B), of more than 0.4 but not exceeding x/6 wherein V is the average volume ( u m 3 ) of the particles and D is the average maximum particle diameter (µm) of the particle, and (c) an average particle diameter of 0.3 to 4 µm, and (III) 0.005 to 1% by weight, based on the aromatic polyester, of inert fine particles having an average particle diameter of 0.01 to 1 µm but being smaller than the average particle diameter of the silicone resin particles.
Claim 13
Dependent Claim
26 words
A magnetic recording medium comprising the biaxially oriented film of claim 1 or 10 and a magnetic layer on one or both surfaces of the film.
References Cited (Backward Citations)
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