Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C57/00—Shaping of tube ends, e.g. flanging, belling or closing; Apparatus therefor, e.g. collapsible mandrels
  • B29C57/12—Rim rolling
• • 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
  • B65D3/00—Rigid or semi-rigid containers having bodies or peripheral walls of curved or partially-curved cross-section made by winding or bending paper without folding along defined lines
  • B65D3/22—Rigid or semi-rigid containers having bodies or peripheral walls of curved or partially-curved cross-section made by winding or bending paper without folding along defined lines with double walls; with walls incorporating air-chambers; with walls made of laminated material
• • 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
  • B65D3/00—Rigid or semi-rigid containers having bodies or peripheral walls of curved or partially-curved cross-section made by winding or bending paper without folding along defined lines
  • B65D3/28—Other details of walls
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C2793/00—Shaping techniques involving a cutting or machining operation
  • B29C2793/0054—Shaping techniques involving a cutting or machining operation partially cutting through the material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C59/00—Surface shaping of articles, e.g. embossing; Apparatus therefor
  • B29C59/02—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing
  • B29C59/04—Surface shaping of articles, e.g. embossing; Apparatus therefor by mechanical means, e.g. pressing using rollers or endless belts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/712—Containers; Packaging elements or accessories, Packages
  • B29L2031/7132—Bowls, Cups, Glasses

Definitions

• This invention relates to an improved cup. Specifically, the invention concerns an improved rim structure for a cup made from a material having at least one foamed layer and at least one non-foamed layer.
• cup technology permits the use of structures consisting of layers of different materials, for example, a foamed layer coincident with a non-foamed layer wherein the different layers have different properties.
• one layer may be a polystyrene foam while the other layer is a non-foamed polystyrene layer forming a plastic skin.
• Cups made from a combined foamed and non-foamed plastic material generally have the foam layer - 2 -
• an improved cup-like container has a side wall, an open mouth defined by the upper portion of the side wall and closing means for closing the bottom of the side wall in a liquid tight manner, thus defining a conventional drinking cup container.
• the closing means may be any means commonly used and well-known in the prior art to make either one-piece cups or two-piece cups.
• Most drinking cups include a rim or thin tight bead around the mouth of the cup.
• the present invention provides a plurality of score lines formed in the side wall, parallel to the circumferential direction of the side wall, adjacent the - 3 -
• the score lines are preferably formed by creasing the side wall material so that the score lines will weaken the side wall.
• the scored upper portion of the side wall is reversely folded into a thin tight bead which surrounds the open mouth of the cup-like container to form a smooth, curved rim.
• the cup is made from a coextruded material having a foamed plastic resin layer and a non-foamed plastic resin layer.
• the non-foamed layer may be either on the inside or on the outside of the cup according to specific end use requirements.
• the score lines are preferably formed in the direction of bending, that is, in the outside layer when a reversely folded rim is formed. A reversely folded rim is one which is curled towards the outside of the cup.
• Figure 1 is an elevational view partly in section of a cup-like container in accordance with the present invention.
• Figure 2 is a detail of the side wall of the cup shown in Figure 1.
• Figure 3 is a schematic view illustrating the formation of score lines in a web of material to be formed into a cup.
• Figure 4 is a detailed view of the tool used to form the score lines.
• Figure 5 is a detailed view of the score lines formed in a web of material.
• Figure 6 is a fragmentary enlarged sectional view of a cup side wall and rim according to the present invention.
• cup 10 is shown in Figure 1 constructed in two parts, including a sidewall 20 and a sealed bottom disc 11.
• cup 10 may be made as a one-piece cup in accordance with well-known manufacturing proce ⁇ dures.
• Cup 10 is manufactured using known techniques as disclosed in the U.S. patents cited above.
• the rectangular side wall blanks are severed from a web of sheet material having a biaxial ori ⁇ entation, that is, an orientation in both the longitudinal and transverse directions.
• the orientations in each direction need not be to the same degree.
• a cylindrical sleeve is formed from the blank with the machine direction of the web extending circumferentially around the cylindrical sleeve.
• a liquid tight lapped seam is formed between the ends of the sleeve such as by heat sealing.
• the sleeve is then placed over a forming mandrel having an outer surface corresponding to the desired configuration of the inner surface of the side wall of the cup to be formed.
• the sleeve while it is so positioned over the mandrel, is heated to cause it to heat shrink into conforming face-to- face contact with the forming surface of the mandrel.
• the shrunken sleeve is stripped from the mandrel.
• a separate bottom closure may be affixed to the side wall while the sleeve is still in position on the mandrel or after it is removed by any of several known cup manufacturing techniques. Alternatively, a one-piece cup may be formed.
• Cup 10 contains a rolled, reversely curled rim shown generally at 12, and also shown in section at 13.
• Stacking shoulder indents 14, also shown in cross-section at 15, may be provided at the bottom of sidewall 20, as shown in Figure 1. Such indents are provided to improve nesting of one cup within another.
• the cup body or sidewall 20 is preferably made from a rectangular blank of oriented polystyrene material extruded with a non-foamed skin layer 21 of solid polystyrene and a layer 22 of polystyrene foam coextruded with layer 21.
• polystyrene is a preferred material, other thermoplastic polymeric materials also may be used.
• the invention is equally applicable to materials having more than two layers, such as a mate ⁇ rial having a layer of foamed material sandwiched between two layers of a non-foamed material. - 5 -
• the layers may be laminated rather than coextruded or formed using other fabrication techniques.
• a multi-layer, i.e., a material having more than two layers may be used.
• foamed layer 22 makes up approximatley 96% of the total caliper of the coextruded sheet and non-foamed or solid layer 21 approximates 4% of the total caliper.
• a separate extruder may be used to supply solid layer 21 by means of cross over pipes so as to surround the foamed extruded material just prior to exiting the annular die.
• the extruded layers are given a biaxial orientation in both the machine, i.e., lengthwise, direction as well as the transverse direction of the sheet of material, that when heated, a formed cylindrical sleeve will properly shrink into conformance with a mandrel.
• the orientation in the machine direction may readily be imparted to the web of material by engaging the material while it is at a suitable orientation tempera ⁇ ture between opposed counter rotating rolls which are driven at periph ⁇ eral speeds substantially in excess of the linear speed of the thermoplastic material leaving the extruder. Additional longitudinal ori ⁇ entation and transverse orientation is provided as the sheet leaves the extruder die, all as is well understood in the art.
• a web 30 of coextruded material is scored in the area subsequently to be curled into rim 12 of cup 10 with a series of parallel lines 33.
• a driven wheel 31 having parallel bosses or projections 32 may be used to form score lines 33.
• projections 32 are positioned approximately 1/32" apart on centers contoured such that a .005" flat occurs as the edge of an included angle of 60 ° with a projected depth of 1/32".
• the preferred configu ⁇ ration of projections 32 is shown more particularly in Figure 4.
• the depth of score lines 33 may be further controlled by adjusting the - 6 -
• score lines 33 are formed in the direction of bending. When a reversely folded rim is used, as shown, the score lines are in whichever layer is on the outside of the cup sidewall.
• FIG. 6 illustrates rim roll 12 in detail showing score lines 33 formed in the upper portion of sidewall 20.
• the upper por ⁇ tion of sidewall 20 is reversely folded into a thin tight bead which surrounds the mouth of cup 10.
• a rimming or curling tool presses the upper scored portion of sidewall 20 first downwardly and outwardly, and then is contoured to force the material back toward the cup sidewall, and then upwardly to finally provide a smooth rim curl contour.
• Scoring lines 33 cause a weakening of the more resistant solid sheet layer 21 during the curling operation allowing the softer outer foam layer to curl around in a generally circular fashion without buckling of the solid layer.
• Score lines 33 predetermine the position where creasing of the solid layer occurs during the ri m curling operation to prevent inconsistent, randomly deformed rim curl shapes. Score- lines 33 weaken solid layer 21 so that rim 12 will have a smooth more pleasing appearance. Also, the smooth uniform contour of rim 12 ensures superior dimensional reliability of the rim diameter and the rim vertical thickness, which are important for lid design and manufacture to a leak-tight fit. A conventional lid would not effectively seal a cup having a randomly deformed rim.
• solid layer 21 When solid layer 21 is on the outside of the finished cup as shown in Figures 1, 2 and 6, the outside surface of the finished fabri ⁇ cated cup permits a more pleasing glossy surface highly receptive to good quality printing using known flexographic or gravure printing techniques for decoration. Alternatively, solid layer 21 may be within the finished cup upon fabrication for certain end product applications. - 7 -

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

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• 1986
  • 1986-03-18 GB GB8629782A patent/GB2187083B/en not_active Expired
  • 1986-03-18 DE DE19863690205 patent/DE3690205T1/de not_active Withdrawn
  • 1986-03-18 AU AU56241/86A patent/AU582845B2/en not_active Ceased
  • 1986-03-18 JP JP50216186A patent/JPS63500164A/ja active Pending
  • 1986-03-18 EP EP19860902186 patent/EP0217864A1/de not_active Withdrawn
  • 1986-03-18 WO PCT/US1986/000541 patent/WO1986006045A1/en active Application Filing
  • 1986-04-15 CA CA000506755A patent/CA1275269C/en not_active Expired - Lifetime

Non-Patent Citations (1)

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