Daiwa Can Company

Bell Polyester Products, Inc.

Masaya Okimoto

Hideaki Tomura

Keita Katsuma

Junji Matsumura

Takashi Kimiduka

Yuji Takeuchi

Sadamu Nakatsuka

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

The present invention provides a polyester resin composition excellent in transparency and flexibility, high in heat resistance, undergoes the bleeding-out of an oligomer at a reduced level, and can be formed into a formed or molded article or pellets that are rarely agglutinated. A polyester resin composition includes a polyester resin, made by a polymerization reaction of a dicarboxylic acid component containing (a) 75 to 98 mol% of an alicyclic dicarboxylic acid, preferably having 5 to 30 carbon atoms, and (b) 2 to 25 mol% of a dimer acid, preferably having 36 or 44 carbon atoms, with (c) a diol component containing 75 mol% or more of an alicyclic diol. The proportion of the trans-form relative to the total amount of the trans-form and the cis-form of the alicyclic dicarboxylic acid unit contained in the polyester resin composition is desirably 80% or more.

Polyester resin composition

Growing community of inventors

Yamaguchi, Japan

Masaya Okimoto