Title:
BIAXIALLY ORIENTED LAMINATED POLYESTER FILM FOR MAGNETIC RECORDING MEDIUM
Document Type and Number:
Japanese Patent JP3655703
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a polyester film for a magnetic recording medium with excellent surface flatness, tape pancake-winding properties, running durability (anti-scraping properties and anti-scratching properties) and electromagnetic transforming characteristics and being inexpensively manufactured.
SOLUTION: A biaxially oriented laminated polyester film wherein polyester layers A (a layer A1 and a layer A2) are respectively laminated on both faces of a polyester layer B is provided and the thickness of each layer is in the order of the layer B > the layer A1 > the layer A2 and 0.001-0.1wt.% particles with large particle diameter, 0.05-0.5wt.% particles with intermediate particle diameter and furthermore, 0.01-0.5wt.% agglomerated particles of small particle diameter with a mean secondary particle diameter of 0.01-0.3μm are incorporated in the polyester layer A and particles with a mean particle diameter of 0.3-3.0μm are incorporated in the polyester layer B and the ratio (T/L) of air passing- through time (T:sec) and degree of mean projected head of projections of inactive particles with intermediate particle diameter (L) is 50-500,000.
Inventors:
Kei Mizutani
Hideaki Watanabe
Hideaki Watanabe
Application Number:
JP15407696A
Publication Date:
June 02, 2005
Filing Date:
June 14, 1996
Export Citation:
Assignee:
Teijin Limited
International Classes:
C08J5/18; B29C55/12; B32B27/36; C08K7/16; C08L67/00; G11B5/73; G11B5/733; B29K67/00; B29K105/16; B29L7/00; B29L9/00; (IPC1-7): B32B27/36; B29C55/12; C08K7/16; C08L67/00
Domestic Patent References:
| JP6223358A | ||||
| JP7214738A | ||||
| JP8104798A |
Attorney, Agent or Firm:
Hideko Mihara