Mitsubishi Chemical Industries Limited

Diafoil Company, Ltd.

Masamichi Watanabe

Seiji Sakamoto

Kunio Bizen

Takuo Nakahara

Akikazu Yano

Yuzo Otani

Seiichi Mukai

Kunihiro Takenaka

Masahiro Kita

Tomiaki Kimura

Yoichiro Yamakawa

There is disclosed a polyester film containing from 0.001% to 4% by weight fine particles of a crosslinked polymer having an average diameter of 0.1 to 5.mu., said fine particles being derived by pulverization from a crosslinked polymer having a specific surface area of at least 1 m.sup.2 /g and a pore volume of at least 0.1 ml/g. The films of the present invention are useful as high grade films and afford many advantages in various applications, for example, as magnetic tapes, capacitors, photography, printing plate making, releasing and the like.

Polyester film containing fine powder of crosslinked polymer

A polyester film is disclosed which comprises a polyester mainly consisting of polyethylene terephthalate and an additive amount of granular calcium terephthalate anhydride particles having a specific volume shape factor. The average particle diameter and additive amount of the granular calcium terephthalate anhydride particles may be controlled so that the film is particularly suitable as a metallized film or a condenser film.

Polyester films

A polyester film is disclosed which comprises (a) a polyester mainly consisting of polyethylene terephthalate which includes first inert particles being precipitated in the polyester-forming reaction system and having an average particle diameter of 1 to 3 microns and which shows a solution haze of 25 to 75% and (b) an additive amount of second inert substance particles which are added to said polyester (a) insoluble in said polyester (a), inert to the polyester-forming reaction and have an average particle diameter of 1 to 5 microns. The film is useful as a base of a magnetic tape.

Polyester films useful as magnetic tapes

Fibers or films with high mechanical strengths are produced from novolacs which are obtained by reaction of resols with phenols under neutral or acidic conditions.

Method for the preparation of fibers or films from phenolic resins

Growing community of inventors

Yokohama, Japan

Masamichi Watanabe