US3762598A - Thermally treated container wall - Google Patents

Thermally treated container wall Download PDF

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Publication number
US3762598A
US3762598A US00190480A US3762598DA US3762598A US 3762598 A US3762598 A US 3762598A US 00190480 A US00190480 A US 00190480A US 3762598D A US3762598D A US 3762598DA US 3762598 A US3762598 A US 3762598A
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United States
Prior art keywords
protective layer
container wall
metal sheet
adhesive
score line
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Expired - Lifetime
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US00190480A
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English (en)
Inventor
H Gayner
D Smith
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Alcoa Corp
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Aluminum Company of America
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D51/00—Making hollow objects
    • B21D51/16—Making hollow objects characterised by the use of the objects
    • B21D51/38—Making inlet or outlet arrangements of cans, tins, baths, bottles, or other vessels; Making can ends; Making closures
    • B21D51/383—Making inlet or outlet arrangements of cans, tins, baths, bottles, or other vessels; Making can ends; Making closures scoring lines, tear strips or pulling tabs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B32B15/085—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin comprising polyolefins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D51/00—Making hollow objects
    • B21D51/16—Making hollow objects characterised by the use of the objects
    • B21D51/38—Making inlet or outlet arrangements of cans, tins, baths, bottles, or other vessels; Making can ends; Making closures
    • B21D51/44—Making closures, e.g. caps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B1/00—Layered products having a non-planar shape
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/04—Interconnection of layers
    • B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
    • B65D17/00—Rigid or semi-rigid containers specially constructed to be opened by cutting or piercing, or by tearing of frangible members or portions
    • B65D17/28—Rigid or semi-rigid containers specially constructed to be opened by cutting or piercing, or by tearing of frangible members or portions at lines or points of weakness
    • B65D17/401—Rigid or semi-rigid containers specially constructed to be opened by cutting or piercing, or by tearing of frangible members or portions at lines or points of weakness characterised by having the line of weakness provided in an end wall
    • B65D17/4012—Rigid or semi-rigid containers specially constructed to be opened by cutting or piercing, or by tearing of frangible members or portions at lines or points of weakness characterised by having the line of weakness provided in an end wall for opening partially by means of a tearing tab
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/70—Other properties
    • B32B2307/704—Crystalline
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2311/00—Metals, their alloys or their compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2323/00—Polyalkenes
    • B32B2323/10—Polypropylene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2439/00—Containers; Receptacles
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T156/00—Adhesive bonding and miscellaneous chemical manufacture
    • Y10T156/10—Methods of surface bonding and/or assembly therefor
    • Y10T156/1052—Methods of surface bonding and/or assembly therefor with cutting, punching, tearing or severing
    • Y10T156/1062—Prior to assembly
    • Y10T156/1064—Partial cutting [e.g., grooving or incising]

Definitions

  • ABSTRACT A method of fabricating a container wall having an integral opening device by providing a metal sheet having an adhesive material secured to one surface thereof.
  • the adhesive secures a continuous protective layer to the metal sheet.
  • the protective layer is selected from the group consisting of partially crystalline polyolefin, partially crystalline polyolefin-e'thylene copolymers, polyethylene acrylate and ionomers of polyolefin. Scoring the sheet to define a removable sector therein while preventing fracture of the adhesively secured protective layer.
  • the protective layer is stress relieved by this thermal treatment which substantially completely eliminates mi crovoids established in the protective layer during the scoring operation. Effecting the heating operation in such a fashion as to improve adhesive bonding of the protective layer, resist diaphragming of the protective layer and reduce feathering of the protective layer along the line of severance when the removable sector is fractured.
  • a container wall structure made by the process of this invention including the adhesive being selected from the group consisting of epoxy, polyester and polyurethane.
  • the protective layer having a crystallinity in excess of about 50 percent.
  • the adhesive bond between the protective layer and the metal sheet removable sector being of greater strength than the shear strength of theprotective layer in regions underlying the score line to prevent substantial diaphragming and to limit feathering to less than about one-thirty-second inch.
  • This invention relates to a thermal treatment process for laminated container walls having integral opening devices and the product thereof. More specifically, this invention relates to a post-heating process which improves the opening characteristics of the laminated container wall and produces improved barrier properties.
  • the undersurface of the end is coated with a suitable protective coating prior to conversion of the wall to provide the integral opening device.
  • a suitable protective coating Prior to conversion of the wall to provide the integral opening device.
  • the protective coating must have its integrity maintained in order to avoid corrosion hazards during use of the container wall. Such hazards can be produced by corrosive attack on the metal by the container contents and, also, galvanic corrosion where bimetallic container assemblies are employed. It is, therefore, necessary in such conventional fabricating systems to provide a supplemental process step in which the damaged coating is repaired. This approach has involved the need to employ extra equipment and an extra process step to apply additional material which fills the voids and repairs the coating.
  • thermal treatment may be beneficial in healing physical cracks created through an enamel coating during the formation of container walls from enamel coated sheet. See U.S. Pat. No. 2,086,165.
  • This disclosure did not involve a container wall which was subjected to the severe forces of scoring and rivet forming which are encountered in forming a removable sector.
  • it was concerned solely with a process which melts the enamel material in order to provide flow of the same into the cracks created during shaping of the article.
  • the thermal process and resultant product of this invention have filled the above-described need.
  • the process involves providing a metal sheet having an adhesive material secured to one surface thereof and securing to the metal sheet a continuous protective layer.
  • the protective layer is preferably a film selected from the group consisting of partially crystalline polyolefin, partially crystalline polyolefin-ethylene copolymers, polyethylene acrylate and ionome'rs of polyolefin.
  • the metal sheet is scored to define a removable sector therein, while preventing fracture of the adhesively secured protective layer.
  • the composite metal sheet is heated to a temperature of about 275 to 375 F for a period of about 0.2 second to 4 minutes, preferably about 300 to 350 F for about 0.5 to 3 min utes.
  • This thermal treatment serves to provide stress relief for the protective layer whichsubstantially completely eliminates microvoids established in the protective layer during the scoring operation and any integral rivet forming operation.
  • FIG. 1 is a plan view of a type of laminated container walls of this invention.
  • FIG. 2 is a fragmentary cross sectional illustration of a form of laminated wall of this invention showing a scored portion thereof taken through 22 of FIG. 1.
  • FIG. 3 is a fragmentary cross sectional illustration taken through 3-3 of FIG. 1 showing an integral rivet portion of a laminated container wall of this invention but with a slightly modified form of tab profile.
  • FIG. 4 is a fragmentary cross sectional illustration showing the scoring process.
  • FIG. 5 is a fragmentary cross sectional illustration of a container wall showing undesirable microvoids in the protective film region underlying the score line.
  • FIG. 5a is an enlarged fragmentary cross sectional illustration of a portion of the protective layer shown in FIG. 5.
  • FIG. 6 shows a fragmentary cross sectional illustra- .tion of a container wall having undesirable diaphragming characteristics.
  • FIG. 7 is a fragmentary plan view of a container wall of this invention shown after the removable sector has been severed and withdrawn.
  • FIG. 8 is a fragmentary cross sectional illustration taken through 88 of FIG. 7.
  • container wall and words of similar import shall refer to wall portions of containers which are provided with opening devices and shall include can ends, jar and bottle closures and other forms of container portions meeting these specifications.
  • FIGS. 1 and 2 there is shown a can end having a top panel 2 and an annular chuck wall 4 which terminates in a radially outwardly directed flange 6.
  • the top panel 2 is provided with a score line 8 which defines a removable sector 10.
  • removable sector shall refer to sectors which are completely severable from the remainder of the container wall, as well as sectors which are adapted to be partially severed and displaced sufficiently to permit access to the container contents without completely separating the same from the container wall.
  • the removable sector 10 may be defined by one or more score lines or weakened lines provided by another fashion so long as residual metal is retained in the panel at the location of the score or weakened lines.
  • a pull tab 14 has an opening 16 adapted to facilitate manual engagement thereof at one end and a securing portion 18 through which fastening means, such as integrally formed rivet 20, may pass in securing the pull tab 14 to the top panel 2.
  • the pull tab In initiating score line fracture, the pull tab is grasped in the region of opening 16 and raised in order to cause the radially innermost portion of the removable portion 10 to be severed through fracture of score line 8. Sequential severance of the remainder of score line 8 permits complete separation of removable sector 10.
  • the top panel 2 has a pair of elongated hollow stiffening ribs 12 disposed on opposite sides of the tear strip 10.
  • the type of removable sector shown in FIG. 1 is that which would generally be employed with pourable container contents. The invention, however, is equally applicable to removable sectors which encompass substantially all of the top panel 2 including the so-called full panel pull out container walls.
  • FIGS. 2 and 3 there is shown a portion of the container wall illustrated in FIG. 1.
  • the container wall has a metal sheet or panel portion 22 which is provided with an adhesive layer 24.
  • the metal sheet 22 is preferably composed of aluminum or steel, as well as alloys thereof. In a typical structure an aluminum-magnesium alloy in a thickness of about 0.008 to 0.0135 inch in the unscored portions is employed. The residual material 28 underlying the score line 8 would have a metal thickness of about 0.0025 to 0.0045 inch.
  • metal sheet as employed herein will be used to refer to both the individual sheet elements out of which an individual container wall will be formed and also to the parent stock out of which a number of individual container walls may be formed. While in general it will be most convenient to establish the composite adhesively bonded material and then sever individual container wall blanks which are substantially scored, riveted and converted to container walls, this preferance is in no fashion critical to the practice of the present invention.
  • the adhesive layer 24 may conveniently be applied as a coating.
  • the adhesive material 24 is preferably applied in an amount of about 1.0 to 5.0 mg/in with about 1.0 to 3.0 mg/in being the preferred amount.
  • the adhesive is preferably selected from the group consisting of epoxy, polyester and polyurethane. It will be appreciated that various additives, catalysts and modifying agents may be employed with the adhesives, should the same be desired. An epoxy modified polyurethane adhesive employed with a conventional catalyst, for example, has been found to be effective.
  • the protective layer 26 is preferably continuous and is preferably substantially continuously bonded to the metal sheet 22 by means of the adhesive 24.
  • the protective' material 26 is preferably selected from the l group consisting of partially crystalline polyolefin, partially crystalline polyolefin-ethylene copolymers, polyethylene acrylate and ionomers of polyolefin.
  • the specifically preferred materials are polypropylene and a polypropylene-ethylene copolymer wherein the ethylene content is about 2 to percent, by weight, with an ethylene content of about 2 to 5 percent, by weight, being preferred.
  • the protective material will preferably have a crystallinity of about 50 to 60 percent, with about 50 to 40 percent being amorphous.
  • the protective layer 26 is preferably applied as a film. Generally the layer 26 will have a thickness of about 1 to 4 mils with about 2.5 to 3.5 mils being preferred for maximum performance at the lowest material cost.
  • FIG. 3 there is shown a portion of the top panel 2 of FIG. 1 including the integral rivet and the pull tab 14.
  • the rivet 20 is provided with a transverse wall 30 and rivet sidewall 32.
  • Thesidewall 32 passes through an opening in the pull tab 14 andthe enlarged head portion provided by transverse wall 30 and the upper portion of sidewall 32 serve to complete the mechanical joint and resist relative separating movement of the pull tab 14 and top panel 2.
  • the transverse wall 30 has a thickness which is slightly less than the thickness of the top panel 2 and substantial deformation of top panel 2 has been effected in the local region where the rivet 20 appears. While the rivet may be formed by a number of conventional rivet forming techniques, it will be appreciated that the barrier properties of the protective layer 26 will be maintained in this region of severe mechanical forming which has been subjected to the application of substantial forces.
  • FIG- 4 there is shown a pairof complementary tools employed toeffect scoring in the top panel 2.
  • An underlying anvil 36 having a flat upper surface cooperates with an overlying indenter tool 38 to establish score line 8, while retaining score line residual material 28.
  • the score line is established by creating a relative closing movement between the indentertool 38 and anvil 36 in such a fashion as to provide a high impact force to the localregion sto be scored. This force may frequently create a pressure of about 100,000 to 300,000 pounds per square inch.
  • the score line 8 is created by severance and physical dislocation of portions of the panel and/or compressively established flow of metal away from the score line region. In any event, it is desired that the final product have an intact protective layer 26 effectively adhesively bonded tothe metal sheet 22, even in regions underlying the score line 8.
  • FIGS. 5 and 5a there is shown the score line 8 and an underlying portion of the protective material 26 which is illustrated as having a plurality of micrscopic voids 42 (shown in somewhat distorted enlarged fashion for clarity of illustration). It is believed that these voids will in most cases contain a vacuum.
  • FIG. 5a it is seen that in the region designated A, the protective layer 26 has a thickness T which amounts to the full web thickness of the protective layer 26. This full thickness T serves as a barrier to passage of potentially corrosive materials through the layer. As the penetration of a given potentially corrosive material through protective layers 26 is related to the thickness of the material, region A provides maximum resistance to such penetration.
  • region B has microvoids 42 which reduce the effective thickness of the protective layer 26 and therefore provide local reductions in barrier effectiveness in regions underlying the score line 8 as well as regions adjacent to the areas of heavy force application.
  • the microvoids 42 do not provide physical openings in the barrier material which would permit direct contact with the undersurface of metal sheet 22 they do reduce the effective barrier thickness in these regions. They serve to create an undesired path through which potentially corrosive materials may pass in order to reach metal sheet 22.
  • the thermal treatment process of this invention involves post-heating of the container wall, preferably after both scoring and rivet information have been effected and the container wall is converted to its final structural form. Heating is effected at about 275 to 375 F for a period of about 0.2 second to 4 minutes and preferably is effected at about 300 to 350 F for about 0.5 to 3 minutes.
  • Heating effects a thermally induced stress relief which substantially completely eliminates the microvoids established in the protective layer 26 resulting from the molecular structural distortion which occurs during scoring, rivet forming and possibly during wall forming.
  • Thermal treatment within this range is believed to produce no ultimate change in the percentage of crystalline structure which exists in the protective layer 26. It serves to restore the structure to one approximating the original molecular state and eliminate the undesired dislocations which occur as a result of the difference in rate of movement between the crystalline and amorphous phases during scoring and rivet information.
  • diaphragming shall refer to the creation of unbonded regions between the metal panel 22 and the protective layer 26 of sufficient size to provide a void therebetween. More specifically, diaphragming will be employed to refer to such unbonded regions which occur between the undersurface of the removable sector and the underlying portion of the protective layer 26.
  • the protective layer 26 underlying the removable sector 10 has an unadhered portion 44 which is disposed in spaced un' derlying relationship with respect to panel undersurface portion 46. While the adhesive 24 has been shown as adhered to unadhered portion 44, it might have adhered to removable sector 10 or partially to portion 44 and partially to sector 10. The manner in which the bond fails is not critical.
  • FIGS. 7 and 8 another advantage produced by the thermal treatment process of this invention will be considered. It has been noticed that with respect to some laminated container wall structurespwhich do not have diaphragming infirmities, an
  • the container panel 2 has had the removable sector 10 (not shown in this view) separated therefrom in order to establish an opening 50in the metal panel 2, which is defined by the remaining portion 8' of the score line 8.
  • the underlying protective material 26 has been stretched transversely inwardly and partially upwardly with respect to opening 50 and defines a smaller opening 52.
  • feathering shall be used to refer to the projection of the protective layer 26 into the opening 50 in order to define a restricted opening 52. While a certain minor degree of feathering is not objectionable, any feathering which materially restricts opening 50 in such a fashion that restricted opening 52 is substantially smaller is objectionable.
  • the feathered projection 56 of protective layer 26 extends into opening 50 by a distance C, when considered in plan, and restricts opening 50 to that extent. It is generally desirable to restrict the average feathered projection 56 in such a fashion that the dimension C will be less than about one-sixteenth inch, with less than about one thirty-second inch being preferred. It has been found that the thermal posttreatment of this invention produces'a substantial improvement in reducing the extent of feathering. Posttreatment at the temperatures recited above will generally restrict the amount of feathering to the preferred limits.
  • EXAMPLE 1 Several groups of aluminum can ends made from an aluminum-magnesium alloy in the extra hard H19 temper (505 lHl9) were provided with one of several types of laminated films. The films were secured to the aluminum ends by means of an epoxy modified, polyurethane adhesive. The ends in Groups A, C and E were provided with a 3 mil polypropylene film and the ends in Groups B and D were provided with a 3 mil polypropylene-3 percent ethylene, by weight, copolymer film. The ends were scored in a conventional fashion to define removable sectors therein. Integral rivets were formed in the ends in a conventional fashion.
  • the metal sheets out of which the ends in Groups A and B were made were laminated at a laminating roll temperature of about 225 F, while the sheets out of which the Groups C, D and E ends were made were laminated at a laminating roll temperature of about 300 to 320 F.
  • Example 2 The tests performed in Example 1 were repeated with the use of a slightly modified anvil die structure which had a large radius of curvature rather than being flat. The following results were obtained:
  • the thermal treatment process of this invention and the resultant product provide improved barrier properties for the protective layer as well as providing improved adhesive bonding between the metal sheet and the protective layer.
  • undesired opening characteristics Such as diaphragming and feathering are eliminated with the result being improved opening characteristics for the container wall. All of this is accomplished by the specific stress relieving, thermal post-treatment of this invention which is believed to substantially completely eliminate molecular structural dislocations established within the protective layer during severe mechanical working of the container wall. This is accomplished without permanently effecting a meaningful alteration in the crystallinity of the protective layer. All of this is accomplished in an economical fashion without requiring major investment in additional equipment or the use of additional materials such as would be required in connection with repair coating practices.
  • a container wall structure comprising a metal sheet having a score line defined removable sector
  • said adhesive composed of a material selected from the group consisting of epoxy, polyester and polyurethane,
  • said continuous protective layer composed of a material selected from the group consisting of partially crystalline polyolefin, partially crystalline polyolefin-ethylene copolymers, polyethylene acrylate and ionomers of polyolefin,
  • said protective layer having a crystallinity in excess of about 50 percent
  • said adhesive bond between said protective layer and said metal sheet removable sector being of greater strength than the strength of said protective layer in regions underlying said score line, whereby severance of said score line and displacement of said removable sector automatically establishes severance of said underlying protective layer without substantial diaphragming and without feathering exceeding about one thirty-second inch.
  • the container wall structure of claim 1 including said protective layer has a thickness of about 2.5 to 3.5 mils in regions not underlying said score line, and
  • said protective film is selected from the group consisting of polypropylene and a polypropyleneethylene copolymer having an ethylene content of about 2 to 10 percent by weight.
  • said protective layer having stress relieved properties resulting from thermal treatment at about 275 to 375 F for about 0.2 second to 4 minutes and having greater barrier properties than would be present in the protective layer in the absence of said thermal treatment.
  • the container wall structure of claim 3 including said protective layer having stress relieved properties resulting from thermal treatment at about 300 to 350 F for about 0.5 to 3 minutes,
  • said bond between said protective layer and said metal sheet is substantially continuous
  • said protective film is a polypropylene-ethylene copolymer having an ethylene constituent of about 2 to 5 percent by weight.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Containers Opened By Tearing Frangible Portions (AREA)
  • Laminated Bodies (AREA)
  • Filling Or Discharging Of Gas Storage Vessels (AREA)
  • Closures For Containers (AREA)
US00190480A 1971-10-19 1971-10-19 Thermally treated container wall Expired - Lifetime US3762598A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US19048071A 1971-10-19 1971-10-19

Publications (1)

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US3762598A true US3762598A (en) 1973-10-02

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US00190480A Expired - Lifetime US3762598A (en) 1971-10-19 1971-10-19 Thermally treated container wall

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US (1) US3762598A (enrdf_load_stackoverflow)
JP (1) JPS4849590A (enrdf_load_stackoverflow)
AR (1) AR209735A1 (enrdf_load_stackoverflow)
AU (1) AU458694B2 (enrdf_load_stackoverflow)
BE (1) BE790027A (enrdf_load_stackoverflow)
BR (1) BR7207101D0 (enrdf_load_stackoverflow)
CA (1) CA952831A (enrdf_load_stackoverflow)
DE (1) DE2250595B2 (enrdf_load_stackoverflow)
FR (1) FR2156726B1 (enrdf_load_stackoverflow)
GB (1) GB1376514A (enrdf_load_stackoverflow)
IT (1) IT966261B (enrdf_load_stackoverflow)
NL (1) NL153477B (enrdf_load_stackoverflow)
SE (1) SE399389B (enrdf_load_stackoverflow)
SU (1) SU638250A3 (enrdf_load_stackoverflow)
ZA (1) ZA726588B (enrdf_load_stackoverflow)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3891117A (en) * 1974-05-24 1975-06-24 Dorn Co V Easy-opening can end construction
US4210618A (en) * 1975-09-12 1980-07-01 Ab Akerlund & Rausing Method of making tear opening devices for containers
US4267937A (en) * 1975-09-12 1981-05-19 Ab Akerlund & Rausing Tear opening device for containers
US4407893A (en) * 1981-12-03 1983-10-04 United States Pipe And Foundry Company Polyolefin coating containing an ionomer for metal substrates
EP0469774A1 (en) * 1990-07-28 1992-02-05 CarnaudMetalbox plc Method of manufacturing a wall ironed can
USD332402S (en) 1989-09-29 1993-01-12 Cmb Foodcan Plc Can end
US5348809A (en) * 1991-11-08 1994-09-20 Nippon Steel Corporation Sheet steel easy open can lid superior in can openability and not requiring repair coating of inner and outer surfaces
US6045654A (en) * 1995-07-03 2000-04-04 Tetra Laval Holdings & Finance S.A. Method for producing a packaging laminate with barrier properties
US6908005B1 (en) * 1998-10-08 2005-06-21 Schmalbach-Lubeca Ag Temporary burst stoppage in a sheet metal top
US20090047501A1 (en) * 2005-10-19 2009-02-19 Toyo Seikan Kaisha, Ltd. Easy-open end
US20090090729A1 (en) * 2007-10-05 2009-04-09 Li-Hua Tseng Reinforcement Wall for Containers
US20150251803A1 (en) * 2014-03-07 2015-09-10 Ball Corporation End closure with large opening ring pull tab
US20190241309A1 (en) * 2016-07-14 2019-08-08 Gregor Anton Piech Metallic can and associated can lid
US10632520B2 (en) 2014-03-07 2020-04-28 Ball Corporation End closure with large opening ring pull tab
US11225054B2 (en) * 2016-06-28 2022-01-18 Baoshan Iron & Steel Co., Ltd. Method and apparatus for producing film-coated metal plate

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ZA807387B (en) * 1979-12-08 1981-11-25 Metal Box Co Ltd Containers
JPS58183457A (ja) * 1982-04-22 1983-10-26 東洋製罐株式会社 スコア付ヒ−トシ−ル蓋
JPS58160269A (ja) * 1983-02-23 1983-09-22 東洋製罐株式会社 易開封性ヒ−トシ−ル蓋付容器
JPS60110641A (ja) * 1983-11-21 1985-06-17 東洋紡績株式会社 金属蓋付きプラスチック缶の製法
JPS6122721U (ja) * 1984-07-17 1986-02-10 日本製罐株式会社 缶の開口装置
JPH0212189Y2 (enrdf_load_stackoverflow) * 1984-10-01 1990-04-05
JPS61287540A (ja) * 1985-06-11 1986-12-17 昭和電工株式会社 缶様容器の蓋
JPS6252044A (ja) * 1985-08-20 1987-03-06 東洋製罐株式会社 イ−ジイオ−プン蓋付罐体
JPS6252045A (ja) * 1985-08-31 1987-03-06 東洋製罐株式会社 複合アルミ材から成るイ−ジイオ−プン蓋
JPS63125152A (ja) * 1986-11-12 1988-05-28 東洋製罐株式会社 イ−ジイオ−プン蓋
US4890759A (en) * 1989-01-26 1990-01-02 Aluminum Company Of America Retortable container with easily-openable lid
US6666933B2 (en) 1997-04-16 2003-12-23 Crown Cork & Seal Technologies Corporation Can end, and method of manufacture therefor

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3510022A (en) * 1968-10-17 1970-05-05 Paul H Heller Removable tab having a protective coating
US3610462A (en) * 1969-07-17 1971-10-05 Nat Steel Corp Container scoreline and tear edge protection
US3632461A (en) * 1969-05-16 1972-01-04 Aluminum Co Of America Method of making a laminated container wall structure

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL250677A (enrdf_load_stackoverflow) * 1959-04-27 1900-01-01
NL147980B (nl) * 1965-04-27 1975-12-15 Montedison Spa Vellen en banen gelaagde kunststof.

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3510022A (en) * 1968-10-17 1970-05-05 Paul H Heller Removable tab having a protective coating
US3632461A (en) * 1969-05-16 1972-01-04 Aluminum Co Of America Method of making a laminated container wall structure
US3610462A (en) * 1969-07-17 1971-10-05 Nat Steel Corp Container scoreline and tear edge protection

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3891117A (en) * 1974-05-24 1975-06-24 Dorn Co V Easy-opening can end construction
US4210618A (en) * 1975-09-12 1980-07-01 Ab Akerlund & Rausing Method of making tear opening devices for containers
US4267937A (en) * 1975-09-12 1981-05-19 Ab Akerlund & Rausing Tear opening device for containers
US4407893A (en) * 1981-12-03 1983-10-04 United States Pipe And Foundry Company Polyolefin coating containing an ionomer for metal substrates
USD332402S (en) 1989-09-29 1993-01-12 Cmb Foodcan Plc Can end
EP0469774A1 (en) * 1990-07-28 1992-02-05 CarnaudMetalbox plc Method of manufacturing a wall ironed can
US5181409A (en) * 1990-07-28 1993-01-26 Cmb Foodcan Plc Method of manufacturing a wall ironed can
US5348809A (en) * 1991-11-08 1994-09-20 Nippon Steel Corporation Sheet steel easy open can lid superior in can openability and not requiring repair coating of inner and outer surfaces
US6045654A (en) * 1995-07-03 2000-04-04 Tetra Laval Holdings & Finance S.A. Method for producing a packaging laminate with barrier properties
US6908005B1 (en) * 1998-10-08 2005-06-21 Schmalbach-Lubeca Ag Temporary burst stoppage in a sheet metal top
US20090047501A1 (en) * 2005-10-19 2009-02-19 Toyo Seikan Kaisha, Ltd. Easy-open end
US8221872B2 (en) 2005-10-19 2012-07-17 Toyo Seikan Kaisha, Ltd. Easy-open end
US20090090729A1 (en) * 2007-10-05 2009-04-09 Li-Hua Tseng Reinforcement Wall for Containers
US20150251803A1 (en) * 2014-03-07 2015-09-10 Ball Corporation End closure with large opening ring pull tab
US9901972B2 (en) * 2014-03-07 2018-02-27 Ball Corporation End closure with large opening ring pull tab
US10632520B2 (en) 2014-03-07 2020-04-28 Ball Corporation End closure with large opening ring pull tab
US11225054B2 (en) * 2016-06-28 2022-01-18 Baoshan Iron & Steel Co., Ltd. Method and apparatus for producing film-coated metal plate
US20190241309A1 (en) * 2016-07-14 2019-08-08 Gregor Anton Piech Metallic can and associated can lid
US10882658B2 (en) * 2016-07-14 2021-01-05 Gregor Anton Piech Metallic can and associated can lid

Also Published As

Publication number Publication date
AR209735A1 (es) 1977-05-31
DE2250595B2 (de) 1976-05-06
CA952831A (en) 1974-08-13
FR2156726A1 (enrdf_load_stackoverflow) 1973-06-01
NL153477B (nl) 1977-06-15
AU458694B2 (en) 1975-03-06
BE790027A (fr) 1973-04-13
JPS4849590A (enrdf_load_stackoverflow) 1973-07-12
IT966261B (it) 1974-02-11
GB1376514A (en) 1974-12-04
DE2250595A1 (de) 1973-06-14
FR2156726B1 (enrdf_load_stackoverflow) 1976-08-20
AU4574672A (en) 1974-02-21
ZA726588B (en) 1973-06-27
SE399389B (sv) 1978-02-13
NL7213934A (enrdf_load_stackoverflow) 1973-04-25
SU638250A3 (ru) 1978-12-15
BR7207101D0 (pt) 1973-09-13

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