Toyo Seikan Kaisha, Ltd.

Sadao Hirata

Yoshitsugu Maruhashi

Isao Tanikawa

Muneki Yamada

Akira Kishimoto

Fumio Kano

Toru Suzuki

Shunsaku Hirata

Jinichi Yazaki

Shigezo Nohara

Kozaburo Sakano

Yoshihiko Watanabe

Junichi Matsuo

Masami Hirano

Syunsaku Hirata

Takeshi Sugimoto

Setsuko Iida

Yoshimichi Ohkubo

Tamio Asai

Reiko Igarashi

An improvement in a packaging multilayer plastic container comprising a gas-barrier interlayer of an ethylene/vinyl alcohol copolymer and an inner and an outer layer of a moisture-resistant thermoplastic resin such as a polyester sandwiching the interlayer. An intermediary layer comprising particles of a high water-absorbing resin dispersed in a resinous medium is provided between the gas-barrier layer and each of the inner and outer layers. Crosslinked polyacrylic acid or its salt or a vinyl alcohol/acrylic acid (salt) block copolymer, for example, may be used as the highly water-absorbing resin. Because of its high saturation moisture absorption at high temperatures, the highly water-absorbing resin is effective for preventing degradation of the gas-barrier property of the ethylene/vinyl alcohol copolymer during retorting.

Multilayer plastic container

An injection-molded body comprising a layer of an olefin/vinyl alcohol copolymer having a very high molecular weight is obtained by melt-kneading a composition comprising (i) a high-molecular-weight olefin/vinyl alcohol copolymer having a melt flow rate of 0.4 to 6.0 g/10 min as determined at 190.degree. C. and a vinyl alcohol content of 40 to 80 mole % and (ii) a low-molecular-weight olefin/vinyl alcohol copolymer having a melt flow rate of 3.0 to 60 g/10 min as determined at 190.degree. C., which is higher by at least 0.5 g/10 min than that of the high-molecular-weight ethylene/vinyl alcohol copolymer (i), and a vinyl alcohol content of 45 to 85 mole % at a weight ratio of from 98/2 to 40/60, and injecting the melt-kneaded composition into a mold through an orifice.

Injection-molded body of olefin/vinyl alcohol copolymer and process for

In a vessel composed of a thermoplastic polyester such as polyethylene terephthalate, by incorporating a predetermined amount of a terminal amino group-containing polyamide or an amino group-containing compound into the polyester, acetaldehyde formed in the vessel wall can be effectively caught.

Thermoplastic polyester composition having improved flavor-retaining

Disclosed is a polyester vessel having mouth, side wall and bottom portions formed of a polyester composed mainly of ethylene terephthalate units, wherein the thermoplastic polyester is a polyester containing a catalyst residue in an amount smaller than 1000 ppm as the metal, and in the thermoplastic polyester constituting the bottom portion of the vessel, the ratio of the thermal crystallization degree represented by the following formula:

Polyester vessel and package

The present invention is based on the finding that when a multi-layer blow-formed body is heat-treated, cooled and taken out, an intermediate layer of a gas-barrier resin in the multi-layer blow-formed body acts as a heat-insulating layer and if the blow-formed body is cooled from the interior by a cooling fluid, a shape-retaining property necessary for taking out the blow-formed body from the mold can be promptly obtained. A biaxially drawn polyester vessel excellent in the resistance to thermal contraction and gas-barrier properties can be prepared at a high manufacturing speed with a reduced number of steps by preheating or temeprature-adjusting a multi-layer preform comprising inner and outer layers of a polyester composed mainly of ethylene terephthalate units and at least one intermediate layer composed of a gas-barrier resin to a temperature suitable for drawing, carrying out the biaxial draw-blow forming of the preform and the heat treatment of the blow-formed body in a mold maintained at a heat-setting temperature, changing over a compressed fluid for the blow-forming to a fluid for internal cooling, cooling the blow-formed body to a temperature at which deformation is not caused when the blow-formed body is taken out from the mold, while contacting the blow-formed body with the surface of the mold cavity, and taking out the formed body from the mold.

Biaxially drawn polyester vessel having resistance to heat distortion

Disclosed is a multi-layer gas-barrier drawn polyester vessel, which comprises an open end portion, a barrel portion which is molecularly oriented in at least one axial direction and a closed bottom portion, said vessel having inner and outer layers composed of a thermoplastic polyester or copolyester and a gas-barrier intermediate layer composed of an ethylene/vinyl alcohol copolymer having an ethylene content lower than 50 mole %, wherein a copolymer nylon resin or a blend of a plurality of nylon resins is interposed as an adhesive between two adjacent layers.

Multi-layer gas-barrier drawn polyester vessel

Process for preparation of injection molded body of olefin/vinyl alcohol

Disclosed is a coated oriented plastic vessel formed by subjecting a parison, preform or sheet comprising a molecularly orientable thermoplastic resin substrate and a coating layer of a vinylidene chloride copolymer formed on at least one surface of said substrate to a draw-molding operation such as biaxial draw-blow-molding or draw-forming, wherein the coating layer of the vinylidene chloride copolymer has such a molecular orientation tht the sum of two-dimensional orientation coefficients (l+m) in the axial direction and circumferential direction is at least 0.03 as measured according to the polarized light fluorometry and the coating layer is not substantially peeled at the low-temperature burst test conducted at -5.degree. C. This coated oriented plastic vessel is prepared by a process comprising coating an aqueous latex of a vinylidene chloride copolymer on at least one surface of a parison, preform or sheet composed of a molecularly orientable thermoplastic resin, drying the coated latex to form a coated structure and subjecting the coated structure to a draw-molding operation such as biaxial draw-blow-molding or draw-forming at a temperature higher than the glass transition temperature of the vinylidene chloride copolymer but lower than the melting point of the vinylidene chloride copolymer, at which temperature draw-molding of said thermoplastic resin is possible, to thereby from the coated structure into a shape of a vessel while drawing the coating layer.

Plastic vessel having oriented coating and process for preparation

Disclosed is a process for the preparation of a coated oriented plastic container, which comprises coating an aqueous latex or organic solvent solution of a vinylidene chloride copolymer on at least one surface of a parison, preform or sheet for formation of container which is formed by hot molding of a molecularly orientable thermoplastic resin, drying the coated parison, preform or sheet to form a coating layer, and subjecting the formed coated structure to draw molding such as biaxial draw blow molding or draw forming, wherein the coating layer of the vinylidene chloride copolymer is crystallized at the step of forming the coating layer or the draw molding step. In the coated oriented plastic container prepared according to this process, the adhesion of the coating layer of the vinylidene chloride copolymer to the plastic container substrate is highly improved, and even under severe conditions, peeling of the coating layer is prevented. Moreover, the gas barrier property, strength and chemical resistance of the container are prominently improved.

Process for preparation of coated oriented plastic container

Disclosed is a resin composition excellent in its drawability, which comprises (A) a saponified ethylene-vinyl ester copolymer having an ethylene content of 20 to 55 mole % and a saponification degree of at least 95%, (B) a saponified ethylene-vinyl ester copolymer having an ethylene content of 25 to 60 mole % and a saponification degree of at least 90%, the ethylene content of the saponified copolymer (B) being higher by at least 3 mole % than the ethylene content of the saponified copolymer (A), and (C) a polyamide, wherein the weight ratio of the saponified copolymer (A) to the saponified copolymer (B) is in the range of from 90/10 to 10/90 and the weight ratio of the sum of the saponified copolymers (A) and (B) to the polyamide (C) is in the range of from 95/5 to 5/95. The resin compositions have excellent gas barrier properties and can be molded into films or sheets or laminated with other film-forming materials. Molded articles such as cups and other vessels having gas barrier properties can be obtained by molding the laminated films prepared from the resin compositions.

Films, sheets, laminates and molded articles having gas barrier

Disclosed is a function-separated composite vessel excellent in the easy openability, preservability and resistance to the deformation due to reduction of the pressure, which comprises a cup-shaped outer member composed of a paper substrate and a flexible seamless cup-shaped inner member composed of a gas-barrier plastic material, wherein the peripheral wall face of the inner member is substantially exactly fitted in the inner side of the outer member but is not bonded to the wall face of the outer member and an opening of the inner member is bonded to a curl portion or flange portion formed on an opening of the outer member.

Composite vessel excellent in preservability and process for preparation

Disclosed is a resin composition excellent in the drawability, which comprises (A) a saponified ethylene-vinyl ester copolymer having an ethylene content of 20 to 55 mole % and a saponification degree of at least 95%, (B) a saponified ethylene-vinyl ester copolymer having an ethylene content of 25 to 60 mole % and a saponification degree of at least 90%, the ethylene content of the saponified copolymer (B) being higher by at least 3 mole % than the ethylene content of the saponified copolymer (A), and (C) a polyamide, wherein the weight ratio of the saponified copolymer (A) to the saponified copolymer (B) is in the range of from 90/10 to 10/90 and the weight ratio of the sum of the saponified copolymers (A) and (B) to the polyamide (C) is in the range of from 95/5 to 5/95.

Resin composition excellent in drawability

A plastic bottle has as a wall-forming component a layer of a copolymer consisting essentially of 99 to 70% by weight of vinylidene cloride and 1 to 40% by weight of at least one acrylic or methacrylic monomer and further including up to 100 parts by weight of at least one member selected from other ethylenically unsaturated monomers per 100 parts by weight of the total amount of the first two monomers, the copolymer having an oxygen permeability constant of less than 9.times.10.sup.-14 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg as measured at a temperature of 20.degree. C. and a relative humidity of 100% and a water vapor permeability constant of less than 3.times.10.sup.-3 g.multidot.cm/m.sup.2 .multidot.day as determined according to the method of JIS Z-0208. This plastic bottle is obtained by casting an aqueous latex or the like of the above-mentioned copolymer in a bottle mold and drying the cast latex. This aqueous latex may be formed as a coating layer on a preformed plastic bottle. In this plastic bottle, the humidity dependency of the oxygen barrier property is prominently reduced.

Plastic bottles and process for preparation thereof

Disclosed is a process for the preparation of a coated plastic container, which comprises coating an aqueous latex or organic solvent solution of a vinylidene chloride copolymer on at least one surface of a plastic container formed by hot molding of a thermoplastic resin, drying the coating and crystallizing the coating simultaneously with or subsequently to the drying step. In the coated plastic container prepared according to this process, the adhesion of the coating layer of the vinylidene chloride copolymer to the plastic container substrate is highly improved, and even under severe conditions, peeling of the coating layer is prevented. Moreover, the gas barrier property, strength and chemical resistance of the container are prominently improved.

Process for preparation of coated plastic container

Disclosed is a laminated plastic container in the form of a bottle, the wall of which comprises a substrate formed of a melt-moldable plastic material, a coating layer formed on at least one surface of the substrate, said coating layer being composed of a copolymer consisting essentially of 99 to 70% by weight of vinylidene chloride and 1 to 30% by weight of at least one acrylic or methacrylic monomer and further including up to 100 parts by weight of at least one member selected from other ethylenically unsaturated monomers per 100 parts by weight of the total amount of said two monomers, said copolymer having an oxygen permeation coefficient of less than 9.times.10.sup.-14 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg as measured at a temperature of 20.degree. C. and a relative humidity of 100% and a water vapor permeability coefficient of less than 3.times.10.sup.-3 g.multidot.cm/m.sup.2 .multidot.day as determined according to the method of JIS Z-0208, and a protecting surface layer of a film-forming synthetic resin other than a vinylidene chloride resin, which is formed contiguously to said coating layer. This laminated plastic container is excellent in the barrier property to various gases such as oxygen, water vapor, nitrogen and carbon dioxide gas and other properties required for plastic containers. The humidity dependency of the oxygen barrier property is highly improved in this laminated plastic container.

Growing community of inventors

Kamakura, Japan

Sadao Hirata