Toyobo Co., Ltd.

Toyo Boseki Kabushiki Kaisha

Tadashi Nakaya

Yoshitomo Ikehata

Toshiyuki Shimizu

Naonobu Oda

Kenji Kawai

Mahiro Nakano

Takamichi Goto

Hirokazu Oogi

Takamichi Gotou

Tooru Imai

Yuka Sako

It is provided that a biaxially stretched polyester film suitable for uses for which nylon films and other flexible films have conventionally been used and a method for producing the film. A biaxially stretched polyester film made of a polyester resin composition (A) containing not less than 60 mass % of polybutylene terephthalate and having yield stress in a MD of not more than 70 MPa, yield stress in a TD of not more than 70 MPa, rupture strength in the MD of not less than 160 MPa, rupture strength in the TD of not less than 160 MPa, and rupture elongation in the MD and TD of not less than 100%.

Biaxially stretched polyester film and method for producing same

It is provided that a polyester film containing a polyester resin obtained by recycling PET bottles and having high lamination strength and slight unevenness in thickness. A biaxially stretched polyester film comprising 50 wt. % or more and 95 wt. % or less of a polyester resin obtained by recycling PET bottles, wherein the content of an isophthalic acid component in all dicarboxylic acid components in the entire polyester resin composing the polyester film is 0.5 mol % or more and 5.0 mol % or less, and the polyester satisfy the specific intrinsic viscosity, the specific thermal shrinkage rate, the specific refractive index in the thickness direction, and the specific unevenness in thickness.

Polyester film

A heat sealable polypropylene resin laminate film having good toughness and heat sealing strength and energy sufficient for packaging heavy goods, mainly fruits and vegetables, and a package made of such film, is a laminate film having three or more layers, a substrate layer made of a crystalline polypropylene resin, a heat sealable layer having a melting point of not more than 150&#xb0; C., and an intermediate layer. The product of the tensile modulus of elasticity (GPa) in both orthogonal directions of the film is 3.1-6.0 (GPa), and the heat sealing energy is not less than 11N&#xb7;cm/15 mm when the film is sealed, such that the heat sealing strength of the film is not less than 8N/15 mm.

Heat-sealable layered polypropylene resin film and package

Growing community of inventors

Inuyama, Japan

Tadashi Nakaya