Toyo Boseki Kabushiki Kaisha

Yoshinori Takegawa

Norimi Tabota

Katsuhiko Nose

Katsuya Ito

Satoshi Hayakawa

Shigeru Komeda

Katsuaki Kuze

Akito Hamano

Yasuo Yoshinaka

A film roll of a heat-shrinkable polyester film characterized in that the heat-shrinkable polyester film meets the following requirements (1) and (2). (1) When samples are cut off therefrom at an almost equal interval along the longitudinal direction, and immersed in hot water at 85&#xb0; C. for 10 seconds, subsequently in water at 25&#xb0; C. and withdrawn, heat-shrinkage percentages in the maximum shrinkage direction of all the samples are 20% or more. (2) When raw polymers used for production of the film above comprises of a major constitutional unit and one or more sub constitutional units different therefrom; and the content of the primary sub constitutional unit is determined, the content of the primary sub constitutional unit in each sample is more than 7 mole % in 100% of all constitutional units, and when an average of the contents of the primary sub constitutional unit is calculated, the contents thereof of all the samples fall within a range of &#xb1;2 mole % relative to the average.

Heat-shrinkable polyester film roll and a process for producing the same

In heat-shrinkable polyester films, the content of 1,4-cyclohexane dimethanol is 10 to 50% by mole based on the polyhydric alcohol component and that the heat shrinkage factors of a 10 cm square sample of the films in (A) hot water of 75&#xb0; C., (B) hot water of 85&#xb0; C., and (C) hot water of 95&#xb0; C. are 30 to 40%, 50 to 60%, and 65 to 77%, respectively. The films can be produced by drawing under specified conditions.

Heat-shrinkable polyester films

Disclosed is a heat-shrinkable polyester film having a specific composition. A heat shrinkage factor of a 10 cm square sample of the film in a maximal shrinkage direction of the film is not less than 20% under the condition that the sample is immersed in hot water of 85&#xb0; C. for 10 seconds, and then in water of 25&#xb0; C. for 10 seconds. The number of test pieces of the film having a rupture ratio of not more than 5% is not more than 10% to the total number of the test pieces under the condition that a tensile test of drawing the film in a direction orthogonal to the maximal shrinkage direction of the film is conducted with a distance between corresponding chucks of 100 mm, each test piece having 15 mm in width, a temperature of 23&#xb0; C., and a drawing rate of 200 mm/min.

Heat-shrinkable polyester film

The heat-shrinkable polyester film rolls according to the present invention is characterized in that the film rolls have (1) a heat shrinkage percentage at 85&#xb0; C. in the maximum shrinkage direction of 20% or more; (2) a melt resistivity at a temperature of 275&#xb0; C. of 0.70&#xd7;10&#x3a9;&#xb7;cm or less; (3) when samples thereof are cut off at an interval of about 100 m and the fluctuation in thickness in the maximum shrinkage direction is measured, a thickness distribution width represented by the following formula of respective samples of 7% or less.Thickness distribution width=(Maximum thickness&#x2212;Minimum thickness)/Average thickness&#xd7;100 Container-wrapping films excellent in processability and printability can be produced from the heat-shrinkable polyester film rolls in high yield.

Heat-shrinkable polyester film roll

A film roll of a heat-shrinkable polyester film characterized in that the heat-shrinkable polyester film meets the following requirements (1) and (2).

A polyester laminated film with excellent sealing ability is provided. The polyester laminated film comprises a base film of a polyester resin and a sealing film of a polyester composition, said sealing film being disposed on at least one side of said base film, wherein the sealing energy, which is measured when two pieces of said laminated films are joined together with the respective sealing films facing each other, is 300 g.cm/15 mm or more.

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Ohtsu, Japan

Yoshinori Takegawa