Abstract: There is provided an easily adhesive, biaxially oriented laminated polyester film for optical use which has excellent adhesion, transparency and easy slipperiness. The biaxially oriented laminated film has a coating layer formed on at least one surface of an aromatic polyester film, the coating layer containing either a polyester resin, an acrylic resin and wax or a polyester resin and an acrylic resin having an oxazoline group and an alkylene oxide chain.

Abstract: A biaxially oriented polyester film, comprising a polyester containing inert particles, wherein (A) the smallest value of Young's modulus in the planar direction is 5 GPa or more, and the difference between the largest value and the smallest value is 1 GPa or less; (B) the largest value of thermal shrinkage factor when the film is heated at 105° C. for 30 minutes is 0.6% or less, and the difference between the largest value and the smallest value is 0.3% or less; (C) the center line average surface roughnesses (Ra) of the both surfaces of the film are in the range of 2 to 10 nm; and (D) the agglomeration ratio of the inert particles in the film is 30% or less. This film has a flat surface, few large projections formed by the agglomeration of particles, high strength, a small thermal shrinkage factor, rarely experienced an error (D/O), and had excellent head contact and dimensional stability as a base film for flexible disks, particularly high-density magnetic disks.

Abstract: An ultraviolet radiation absorbent is produced by a method including specified Step A, Step B and Step C. Step A is a process of causing an amidation of anthranilic acid and terephthaloyl dichloride in the presence of a solvent and an alkali to generate N,N?-bis(o-carboxyphenylterephthalamid) and separating a solid component containing N,N?-bis(o-carboxyphenylterephthalamid) generated by this amidation. Step B is a process of separating a solid component containing cyclic imino ester compound of a specified kind. Step C is a process of processing the solid component separated in Step B with an alkaline solution and further washing with water to obtain the ultraviolet radiation absorbent for thermoplastic polymers containing cyclic imino ester compound of the specified kind.

Abstract: There is provided a laminated polyester film which is improved in lubricity, transparency, dimensional stability, shock resistance and adhesion, and which comprises a polyester base film comprising polyester and to at least one direction, and a coating layer provided on at least one surface of the base film, wherein said coating layer contains polymer binder and inert particles, the refractive index of the inert particles being substantially same as that of the polymer binder, and wherein the laminated polyester film has a haze of 1.5% or less, a total light transmittance of 85% or more, 50% destructing energy per 100 &mgr;m film thickness of 0.3 J or more, and a thermal shrinkage at 230° C. for 30 minutes of 4% or less.

Abstract: An ultraviolet radiation absorbent for thermoplastic polymer materials such as polyethylene terephthalate or polycarbonate contains cyclic imino ester compound of a specified structure in an amount of over 99.5 weight % and less than 100 weight % and having an acid value in the range of 1×10−3-1 and/or a chlorine ion content in the range of 1×10−1-1×103 ppm.