Toyo Boseki Kabushiki Kaisha

Tsutomu Oko

Norimi Tabota

Hideki Ito

Kuniharu Mori

Hiroshi Nagano

Tsutomu Isaka

Hideki Igushi

Hideki Shimizu

Seizo Takabayashi

Shinichiro Okumura

Mitsuo Inoue

Katsuhiko Nose

Masatoshi Hashimoto

Hiroshi Shibano

Shigeji Konagaya

Koichi Matsunami

Koji Yamada

Kazumoto Imai

Akira Matsuda

Hikoichi Nagano

Haruo Okudaira

Satoshi Osame

Sinitiro Okumura

Hiroaki Esaki

Teruo Kurosawa

Makoto Hachiboshi

Hiroshi Ieki

Tadao Yoneyama

The present invention provides a heat shrinkable polyester film whose hot water shrinkage along its main shrinkage direction is equal to or greater than 20% when the film is put in hot water of 70&#xb0; C. for 5 sec; 35% to 55% when put in hot water of 75&#xb0; C. for 5 sec; and 50% to 60% when put in hot water of 80&#xb0; C. for 5 sec, wherein the compressive strength of the label formed by the film satisfies a following expression (1):Y&#x3e;X&#x2003;&#x2003;(1)

Heat shrinkable polyester film

A label having a thermoplastic polymer film and an ink layer formed on at least one surface thereof, the ink layer being removable in alkaline hot water, can easily be recycled after separated or without being separated from the bottle into polymer pellets with improved purity. The recycled polymer pellets are extremely suitable for the effective use of resources because they contain substantially no ink and can therefore find various applications.

Labels and bottles fitted with them

Polypropylene multi-layer sealant films for retort packaging

A polyester laminate film comprising plural polyester layers, which comprises one surface layer comprising a polyester and a lubricant having an average particle size of 1-3 &mgr;m in a proportion of 1-5 wt % and the other surface layer comprising a polyester wherein 5-15 mol % of the entire acid component is a dimer acid component, the polyester laminate film having a crystallization peak temperature of 80-120&deg; C. under temperature rise of the On The polyester laminate film of the present invention has a lower crystallization peak temperature when the film is under temperature rise, as compared to conventional polyethylene terephthalate. As a consequence, the film is free of whitening upon retorting, even after the film was subjected to remelting treatment and rapid cooling for noncystallization and unorienting. Therefore, the film serves well as a laminate film for food containers and beverage cans that undergo retort sterilization. Inasmuch as the polyester layer on one surface contains a large amount of a lubricant and has releasing property, the film serves well as a laminate film for a metal plate, which is required to have releasing property from a mold during manufacture of containers such as a two-piece can. The polyester layer on the other surface contains a large amount of dimer acid and the film is superior in impact resistance. Hence, the film serves well as a laminate film for a metal container which is susceptible to damage due to impact during distribution process.

Polyester laminate film, metal plate laminated with this film and film-laminated metal container

Polyamide laminated film

A polyester laminate film comprising plural polyester layers, which comprises one surface layer comprising a polyester and a lubricant having an average particle size of 1-3 &mgr;m in a proportion of 1-5 wt % and the other surface layer comprising a polyester wherein 5-15 mol % of the entire acid component is a dimer acid component, the polyester laminate film having a crystallization peak temperature of 80-120&deg; C. under temperature rise of the film The polyester laminate film of the present invention has a lower crystallization peak temperature when the film is under temperature rise, as compared to conventional polyethylene terephthalate. As a consequence, the film is free of whitening upon retorting, even after the film was subjected to remelting treatment and rapid cooling for noncrystallization and unorienting. Therefore, the film serves well as a laminate film for food containers and beverage cans that undergo retort sterilization. Inasmuch as the polyester layer on one surface contains a large amount of a lubricant and has releasing property, the film serves well as a laminate film for a metal plate, which is required to have releasing property from a mold during manufacture of containers such as a two-piece can. The polyester layer on the other surface contains a large amount of dimer acid and the film is superior in impact resistance. Hence, the film serves well as a laminate film for a metal container which is susceptible to damage due to impact during distribution process.

In a thermo-shrinkable polyester film, the thermal shrinkage ratio in a main shrinking direction is about 20% or more after being treated in water of about 70.degree. C. for about seconds, about 35 to about 55% after treated in water of about 75.degree. C. for about 5 seconds, and about 50 to about 60% after being treated in water of about 80.degree. C. for about 5 seconds. After the film is shrunk by about 5% by treatment in water of about 75.degree. C. for about 10 seconds, the probability of the elongation at rupture of the film in the direction perpendicular to the main shrinking direction being about 20% or less, is about 10% or less. The ratio of .tau..sub.1 /.tau..sub.2 is about 0.05 to about 0.45, where .tau..sub.2 is the stress of shrinkage in a main shrinking direction of the film at about 90.degree. C., and .tau..sub.1 is the stress of shrinkage in a direction perpendicular to the main shrinking direction of the film at about 90.degree. C. The sealing strength of the film is about 1.2 kg/15 mm of width or more.

Thermo-shrinkable polyester film

Heat-shrinkable polyester films having a heat shrinkability of 30% or more, preferably 40% or more, in the direction of major shrinkage after treatment in hot water at 80.degree. C. for 30 seconds, the ratio of heat shrinkability in the direction of major shrinkage after treatment in hot water at 80.degree. C. for 5 seconds to heat shrinkability in the direction of major shrinkage after treatment in hot water at 80.degree. C. for 30 seconds being 0.8 or less, preferably 0.7 or less. The heat-shrinkable polyester films are suitable for label applications because of their particular heat-shrinkable properties such that not only do they scarcely cause longitudinal sinking when shrunk but also they have very few wrinkles, shrinkage spots and strains remaining after shrinkage.

Heat-shrinkable polyester films

A drawn film of polyamide having an oxygen permeability coefficient of not more than 5 .times. 10.sup.-13 ml.cm/cm.sup.2.sec.cmHg, a breaking strength of not less than 14 kg/mm.sup.2, a breaking elongation of 30 to 150%, a yield strength of not less than 7 kg/mm.sup.2 and a yield elongation of 2 to 6%, which can be manufactured by drawing an undrawn polyamide film biaxially at a temperature within a certain range and optionally heat treating the resulting drawn film, the said undrawn polyamide film being made of a polyamide having a relative viscosity of about 2.0 to 4.0 when measured with a solution thereof in 96% sulfuric acid at a concentration of 1 g/100 ml at 25.degree. C and containing in the molecule not less than 70% (mol) of the repeating unit constituted with metaxylylenediamine or its mixture with paraxylylenediamine and an .alpha.,.omega.-aliphatic dicarboxylic acid having 6 to 10 carbon atoms, which is useful as a packaging material due to its excellent properties in tensile strength, yield strength, Young's modulus, heat stability, size stability, transparency, gas barrier property, etc.

Meta-xylylene diamine/aliphatic dicarboxylic acid polyamide film

Growing community of inventors

Inuyama, Japan

Tsutomu Oko