Daiwa Can Company

Bell Polyester Products, Inc.

Yuji Takeuchi

Takashi Kimiduka

Junji Matsumura

Takashi Kanehira

Masaya Okimoto

Hideaki Tomura

Keita Katsuma

Hiroko Namekawa

Sadamu Nakatsuka

A package includes: a film including a crystalline stretched oriented film; and a breaking portion provided in the film and including one or more non-oriented portions formed by heating a part of the crystalline stretched oriented film at a temperature equal to or higher than a melting point of the crystalline stretched oriented film and facing each other with an oriented portion of the crystalline stretched oriented film interposed therebetween.

Package and film

The problem to be solved by the present invention is to provide a polyester resin excellent in various properties wherein the film formability is good, film fracture (hairs) and scraping (galling) are not easily generated in the drawing/ironing process when applied to a metal-sheet-coating polyester film, the film surface is not damaged when used as the inner-surface film for a metallic can, and the metallic can is hardly corroded (dent resistance), by dropping or external impact (denting), after a product is made by enclosing contents into the can. The copolyester resin of the present invention is characterized by comprising, as the constituent units, 50 to 93 mass % of (A) ester oligomer with the number-average molecular weight of 700 or lower and consisting of a dicarboxylic acid unit (a1) containing 70 mole % or more of the terephthalic acid component and a diol unit (a2) containing 70 mole % or more of the ethylene glycol component; and 7 to 50 mass % of (B) polyester polyol with the number-average molecular weight of 1500 to 3000 and consisting of a hydrogenated dimer acid unit (b1) and a 1,4-butanediol unit (b2).

Copolyester resin and polyester film for covering metal plates and laminated polyester film comprising same made into film

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Yamaguchi, Japan

Yuji Takeuchi