Toyo Seikan Kaisha, Ltd.

Senji Itoh

Kiyonori Kogashiwa

Fumio Ikushima

Kazuhisa Ishibashi

Kikuo Matsuoka

Tadahiko Katsura

Kazumi Hirota

Yotaro Tsutsumi

Toshifumi Tanabashi

Ichiro Hori

Toshifumi Tanahashi

Toshihiko Hayashi

A sealed laminated vessel is formed from a barrel composed of a laminate including a paper substrate and a metal foil with inner and outer heat-sealable resin layers on both surfaces lapped together to form a straight side seam and a lid member on at least one open end thereof formed from a laminate of a metal foil and heat-sealable resin layer which is heat sealed to a circumferential end edge portion of the barrel. The vessel is formed by a process which includes forming a flat circumferential end portion of the barrel by bending at least one open end of the barrel outwardly and thereafter inwardly bending a part of the bent portion in the reverse direction so that it is lapped on the lower side of the remaining part of the bent portion to form a flat circumferential end portion on at least one open end of the barrel.The lid member is thereafter heat-sealed to the circumferential portion of the barrel through the heat-sealable resin layer of the lid member. Finally, the heat-sealed portion of the lid member and the circumferential end portion of the barrel are mechanically lap-seamed using a molding roller having a section conforming to the final shape of the sealed portion. As a result a horizontal flange wall in the peripheral portion of the lid member is downwardly bent together with the circumferential end portion of the barrel. Accordingly, heat sealing is uniformly effected and the sealing property is further improved by the mechanical lap seaming to form a tightly sealed laminated vessel.

Process for preparing a sealed laminated vessel

In a method for laminating a film of a synthetic resin to the surface of a base metal, the improvement which comprises coating an adhesive synthetic resin powder either as such or as a dispersion in water or in a low-boiling organic liquid on said metal surface and heating the coating to melt the powder, or directly coating said synthetic resin powder in the molten state on said metal surface, thereby to bond the synthetic resin powder thereto, superposing said film of synthetic resin on the resulting coating, heating the assembly under pressure, and then cooling the resulting laminate.

Utilizing particulate adhesive for laminating plastic film to the

A composite material for packaging containers which has excellent sealability, easy openability and excellent flavor-retaining property is provided. The composite material consists of a metallic foil and a thermoplastic resin selected from the group consisting of polyolefinic resins, polyester resins, polyamide resins, polycarbonate resins and mixtures thereof, said thermoplastic resin layer having a thickness of 1 to 20 microns and a surface roughness of not more than 4.0 .mu.m Rmax L0.80 mm. The thermoplastic resin has a carbonyl concentration of 1 to 600 milliequivalents/100 g of resin for the polyolefinic resins, 1,000 to 1,300 milliequivalents/100 g of resin for the polyester resins, 500 to 1,200 milliequivalents/100 g of resin for the polyamide resins and 600 to 800 milliequivalents/100 g of resin for the polycarbonate resins.

Composite material for packaging containers

Disclosed is an easily openable heat seal lid for sealing a vessel proper by forming a heat-sealed portion between the lid and the vessel proper, which comprises a laminate comprising at least an inner face member composed of a thermoplastic resin and a metal foil, wherein scores defining a portion to be opened are formed on the side inner than the portion to be heat-sealed so that the scores extend to the midway of the thickness direction of the metal foil, an opening tab is formed on the portion of the lid to be opened through a bonding fulcrum portion composed of a thermoplastic resin hot adhesive so that the push-tearing top end of the opening tab is located on the scores, and the peel strength between the opening tab and the lid in said bonding portion is at least 0.4 Kg/5 mm.

Easily-openable heat seal lid

Growing community of inventors

Ayase, Japan

Senji Itoh