Abstract: A container body is sealed by means of a lid made of a flexible sheet having an insulative property and an antenna made of an electrically conductive material which is laminated upon the lid. According to this construction, when the container body is exposed to microwaves within a microwave oven, microwave energy is concentrated at a position near the front end of the antenna and the microwave energy is converted into heat energy, whereby the lid is opened by means of the thus converted heat. The lid can thus be precisely partially melted so as to form an opening of a predeterminedly suitable size.

Abstract: A process for manufacturing the butt-welded cans comprises the steps of applying a 0.5 to 3.5 .mu.m thick organic resin film for preventing the adhesion of melted metal particles to at least a 1-mm-wide region from the butt-weld portion edge of at least the inner surface of a steel plate can blank, and butt-welding the edges of the can blank by the use of a laser, or alternatively applying a 0.5 to 7.0.mu.m thick organic resin film, butting the edges of the can blank, and laser-welding the butted edges while a cooling device is brought into contact with the butted edges from the inner side of each can. In this case, it is preferred that the coating material having high thermal decomposition resistance is applied to the whole outer surface of each can, and the weld portion is then butt-welded by means of a CO.sub.2 laser.

Abstract: There is here provided butt-welded cans made of steel plates having a carbon concentration of 0.02 to 0.09% by weight, the aforesaid butt-welded cans being characterized in that a coating film for preventing the adhesion of melted metal particles is applied to at least the inner surface of the weld portion and its vicinity of each can, and a carbon concentration index I of the weld portion satisfies the formula (1)I=(Iw/Ic).times.10.sup.3 .ltoreq.15 (1)wherein Iw is a K.alpha. X ray intensity, of carbon in the weld portion, measured by the EPMA method, andIc is a K.alpha. X ray intensity, of carbon in graphite, measured by the EPMA method.

Abstract: A method and apparatus for guiding the opposed edges of sheet material into substantially abutting edge-to-edge relationship with one another and thereafter welding said edges by a high energy welding source to form a seam. The invention enables the continuous high speed butt welding of the sheet material to form cylindrical bodies. The apparatus includes three elements, a mandrel, a mandrel holder and tube holders. Sheet material is fed to around said mandrel and advanced by a tube holder with an edge of two opposite edges of said sheet material being in intimate contact with a basis plane of said mandrel holder. Another edges is slided into contact with above mentioned edge of sheet material making abutting relationship after passing through the basis plane of said mandrel holder. These abutting edges pass a high energy zone of a welder and butt welded to make a tube.

Abstract: A metallic container composed of a first and a second section each composed of a metallic cup-like fabricated article having a primer coating, the two sections being lap-bonded at their circumferential open end portions by means of a thermoplastic film-like adhesive. A process for producing said metallic container is also provided which comprises a fabricating step of producing the first and second sections, an adhering step of heat-adhering a film-like adhesive to the peripheral surface of the open end portion of the second section to be laid inwardly, and a bonding step of bonding the open end portions of the first and second sections. In the metallic container, the film-like adhesive, forming a circumferential overlapping portion, is adhered to the edge of the open end portion of the second section and its inner circumferential surface following the edge.

Abstract: A can body of surface treated steel plate, such as TFS, having adjacent longitudinally extending edges of tubular shaped member welded by irradiation of laser beam and provided with inside surface of welded seam having reliable paint retaining characteristic and free from projections, such as upset. For the purpose, welding is carried out such that inside and outside width of molten-solidified zone and structure changed zone will be maintained within a predetermined range and that metallic wire or elongated backing strip is located oppositely to lower surface of both edges being butt-welded.

Abstract: There is provided a method of making a welded can body having a mash seam weld which includes a heat affected zone extending continuously in the longitudinal direction thereof and is formed with no pitting. The weld is formed by mash seam welding a lapped portion of a can body preform made of a surface treated steel sheet while allowing an alternating current to flow through the lapped portion via a water-cooled elongated electrode and a water-cooled rotary electrode. The alternating current has a crest factor satisfying an expression 1.5.ltoreq.Ip/Ie.ltoreq.2.0, where Ie and Ip designate an effective value and a peak value, respectively, of the alternating current.

Abstract: There is provided a method of making a metallic container having a predetermined or standard height and a circumferential seam of the type which is formed by fitting a first open end portion of an upper can body having a venting portion and a second open end portion of a lower can body having a bottom portion to each other with a heat sealable adhesive layer therebetween to form a metallic container preform having a fitted portion, and heating the fitted portion thereby to fuse the adhesive layer.

Abstract: 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.

Abstract: A method of, and apparatus for, manufacturing a metal can (1) with an annular seam (5) which is capable of withstanding high internal pressures and resisting chemical action. A piece of thermoplastic tape is heat bonded to the outer surface (10a.sub.3) of the open end portion (10a ) of a first can section (10) so as to leave a portion (11a) projecting therefrom. After being bent radially inwardly of the first can section, the projecting tape portion is further folded back into forced contact with the inner surface (10a.sub.2) of the open end portion of the first can section by means of a mandrel (16). The open end portion of the first can section is then heated, with the fold of the tape held pressed against its inner surface by the mandrel, to cause adhesion of the thermoplastic tape to the outer surface, edge (10a.sub.1), and inner surface of the open end portion of the first can section. An adhesive layer (4) is thus provided.

Abstract: Disclosed is an easily-openable vessel closure comprising a can end member having a preformed opening and an easily-tearable opening tab arranged on the outer side of the can end member to cover the opening and adhere closely to the peripheral portion of the can end member contiguous to the opening, wherein the opening of the can end member has such a size and shape that the opening is longer in the radial direction of the can end member, the opening extends from the inside of a circle concentric with the can end member, which has a diameter 0.

Abstract: Disclosed is a process for preparation of metal vessels, which comprises lap-bonding circumferential open end portions of outer and inner members, each consisting of a formed seamless metal cup, to each other through an adhesive, said process being characterized by fitting both the outer and inner members to each other through an adhesive layer interposed between the open end portions of both the members, heating the fitted portions of both the outer and inner members so as to melt the adhesive layer, and cooling the fitted portions so that the temperatures of the fitted portions of both the outer and inner members are substantially equal to each other just before solidification of the adhesive layer and the adhesive is filled between both the open end portions.

Abstract: Disclosed is a process for the preparation of metal vessels, which comprises lap-bonding both the circumferential end portions of upper and lower members, each consisting of a seamless formed metal cup, through a layer of a hot adhesive interposed therebetween, wherein a high frequency induction heating coil is arranged so that the coil covers a part, smaller than the semicircle, of the circumferential portion to be formed into a seam, which circumferential portion consists of said end portions engaged with each other through the hot adhesive layer, electricity is applied to the heating coil to induce an eddy current passing through said end portions and the circumferential portion and the heating coil are rotated relatively to each other, whereby both the end portions are heated and a seam is formed by heat bonding.

Abstract: Disclosed is an easily openable vessel closure comprising a can end member having a preformed opening, an easily peelable opening piece which is applied to the outer side of the can end member so that the opening piece covers said opening and adheres closely to the peripheral portion of said opening, and a protecting covering layer formed to cover the cut edge of the opening of the can end member, wherein the protecting covering layer is formed of a thermoplastic resin having a heat bondability and the protecting covering layer includes a film layer heat-bonded to the inner and outer peripheral portions of the opening and a projecting cover heat-bonded to the cut edge of the opening integrally with said film layer, and said opening piece is heat-bonded to the can end member through the protecting covering layer located outside the can end member and said protecting covering layer is stuck closely to the cut edge of the opening so that when the opening piece is peeled, the protecting covering layer is left on

Abstract: Disclosed is a process for the preparation of cans which comprises pressing a flexible lid comprising an aluminum foil as a substrate and a heat-sealable resin layer formed on the surface thereof to a metallic can body being formed of a surface-treated ferromagnetic steel plate and having a curl on the edge of an opening in such a positional relation that the curl portion of the can body confronts the resin layer of the lid, and induction-heating the curl portion selectively by a high-frequency induction-heating coil located in the vicinity of the periphery of the curl portion to form a seal between the curl portion and the lid by heat-sealing. According to this process, the curl portion to be heat-sealed is selectively heated, and heat-sealing can be accomplished in a short time while preventing deterioration of a lacquer or sealant.

Abstract: An improvement in a method for producing a welded metallic can body. The method involves holding and pressing a lap portion of the side marginal portions of a can body-like structure, which has been formed by bending a metal blank into a cylindrical shape, along its entire length between a pair of opposing parallel wire electrodes placed on the opposing surfaces of parallel electrodes, and passing an electric current across the parallel electrodes for a predetermined period of time during the pressing to subject the lap portion to resistance welding. At least one of the parallel electrodes is divided longitudinally into two or more portions electrically insulated from each other, and an electric current is passed through at least one of them independently from the other portions so that the temperature rise in the lap portion of the can body-like structure becomes uniform. Also disclosed is an apparatus for producing a welded metallic can body in accordance with the aforesaid method.

Abstract: A continuous heating apparatus for metal caps having at least one pair of high frequency electric conductors where the conductors are separated by an interval smaller than the diameter of the bottoms of the caps to be heated. A guide panel is spaced from the conductors and is adapted to engage the open end of the metal caps when the caps are moved away from the conductors towards the guide panel due to the repulsion effect occurring between the high frequency current in the conductors and current induced in the caps. A transport device moves the metal caps relative to the conductors.

Abstract: A metal cap having a primer layer thereon which has a thermal adhesiveness with respect to a lining layer and wherein part of the lining at the bottom of a cap is thermally adhesively fixed to the primer layer.A method of manufacturing a metal cap including steps of applying a primer to the cap which has a thermal adhesiveness with respect to a lining layer and heating only a portion of the bottom of the cap to cause only part of the lining to become affixed to the primer.

Abstract: A high frequency induction heating apparatus for heating articles where the apparatus has a heating station, a source of high frequency current including a vacuum tube oscillator means and a plurality of high frequency electric conductors which extend through the heating station and which are connected to the source and to ground. The conductors are series connected such that one-half of the conductors form inflow conductors positioned adjacent one another in one-half of the heating station and the remaining one-half of the conductors form outflow conductors positioned adjacent one another in the remaining one-half of the heating station. Conductors connected closer to the source are positioned further from the article to be heated than conductors connected closer to ground in order to prevent dielectric breakdown between the conductors and the article to be heated.

Abstract: A high frequency induction heating circuit for heating a plurality of articles where the heating circuit has a semiconductor oscillation circuit which includes a series resonance circuit having a heating coil and a condensor. A detection circuit for detecting changes in impedance and frequency variations in the heating coil is included as well as a current control circuit which is responsive to the detection circuit. A varible control gain regulation apparatus is included in the current control circuit such that current supplied to the coil becomes a non-constant current control depending on the number of articles to be heated.