WO1983002747A1 - Thermoforming coextruded plastic sheets - Google Patents

Thermoforming coextruded plastic sheets Download PDF

Info

Publication number
WO1983002747A1
WO1983002747A1 PCT/US1983/000158 US8300158W WO8302747A1 WO 1983002747 A1 WO1983002747 A1 WO 1983002747A1 US 8300158 W US8300158 W US 8300158W WO 8302747 A1 WO8302747 A1 WO 8302747A1
Authority
WO
WIPO (PCT)
Prior art keywords
thermoforming
layers
objects
thermoformed
sheet
Prior art date
Application number
PCT/US1983/000158
Other languages
French (fr)
Inventor
Container Corporation Composite
Laszlo J. Bonis
Original Assignee
Composite Container Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Composite Container Corp filed Critical Composite Container Corp
Publication of WO1983002747A1 publication Critical patent/WO1983002747A1/en

Links

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
    • B29C51/00—Shaping by thermoforming, i.e. shaping sheets or sheet like preforms after heating, e.g. shaping sheets in matched moulds or by deep-drawing; Apparatus therefor
    • B29C51/14—Shaping by thermoforming, i.e. shaping sheets or sheet like preforms after heating, e.g. shaping sheets in matched moulds or by deep-drawing; Apparatus therefor using multilayered preforms or sheets
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/07—Flat, e.g. panels
    • B29C48/08—Flat, e.g. panels flexible, e.g. films
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/16—Articles comprising two or more components, e.g. co-extruded layers
    • B29C48/18—Articles comprising two or more components, e.g. co-extruded layers the components being layers
    • B29C48/21—Articles comprising two or more components, e.g. co-extruded layers the components being layers the layers being joined at their surfaces
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/30—Extrusion nozzles or dies
    • B29C48/305—Extrusion nozzles or dies having a wide opening, e.g. for forming sheets
    • B29C48/307—Extrusion nozzles or dies having a wide opening, e.g. for forming sheets specially adapted for bringing together components, e.g. melts within the die
    • 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
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/07—Flat, e.g. panels

Definitions

  • the invention relates to preparing objects thermoformed from p astic sheets.
  • Plastic sheets are often produced by appara ⁇ tus in which plastic material is heated and sup ⁇ plied under pressure to an extrusion die. The sheets can then be thermoformed to a desired shape, and individual objects can be trimmed from the thermoformed sheet.
  • the invention features coextruding a multilayered sheet having adjacent layers of plastics that do not bond to each other during co ⁇ extrusion, thermoforming the multilayered sheet, and separating individual thermoformed objects of different layers.
  • the produc ⁇ tivity of the extrusion, thermoforming, and trim ⁇ ming apparatus is multiplied by the number of layers in the sheet.
  • one of the plastics in the multilayered sheet is polystyrene and another plastic is polypropylene; in some preferred embodiments one plastic is for a separator layer between plastic layers for the thermoformed objects, and in other preferred embodiments the thermoformed objects are made from more than one of the plastics of the layers of the multilayered sheet.
  • the thermoforming of the multilayered sheet with poly ⁇ propylene and polystyrene layers is faster. than the slow, and therefore expensive, thermoforming of polypropylene alone- Description of the Preferred Embodiment
  • draw ⁇ ing is a diagrammatic view of a process of manufacturing plastic objects according to the in ⁇ vention.
  • Two heated containers 16, 18 serve as sources of the polystyrene (70% crystal styrene and ' 30% rub ⁇ ber modifying plastomer sold by Phillips Chemical Company under the trade designation Solprene 416P, a block polymer having a butadiene/styrene ratio of 70/30, a molecular weight of 140 M, a density of 0.94, and a melt flow index of 2 decigrams/ in) , and polypropylene- (available from Rexene Company, Paramus, New Jersey, and having a meltr flow index of 4 decigrams/ in) , respectively.
  • Solprene 416P a block polymer having a butadiene/styrene ratio of 70/30, a molecular weight of 140 M, a density of 0.94, and a melt flow index of 2 decigrams/ in)
  • polypropylene- available from Rexene Company, Paramus, New Jersey, and having a meltr flow index of 4 decigrams/
  • Conduits 20, 22, 24, 26, 28 supply the heated materials to coextrusion block ' 30. There the ma ⁇ terials merge together to form under pressure a unitary, five-layer thick stream ' 32 of generally circular cross section. Stream ' 32 passes into extrusion die ' 34 "(e.g. , Welex standard 54" flex- lip die) for extrusion into continuous sheet ' 36. Sheet ' 36 then passes through a series of chill rolls 38.
  • extrusion die ' 34 "(e.g. , Welex standard 54" flex- lip die)
  • the sheet after coextrusion, may then be thermoformed into bowls or wound into spools (not shown) for storage and later themoforming.
  • thermoforming apparatus 40 the vacuum forming type well known in the art
  • the shaped sheet 42 passes through trim press 44, in which the indivi ⁇ dual bowls 12 and 14 are trimmed. Because the polypropylene and polystyrene of bowls 12, 14, respectively, do not bond to each other during coextrusion or thermoforming, bowls 12, 14 can be easily separated from each other.
  • the simultaneous coextruding of five sheets and thermoforming and trimming of five bowls act to increase the produc ⁇ tivity of the coextrusion, thermoforming, and trimming apparatus. by a factor of five. Also, the thermoforming of the five-layer sheet is faster than the slow, and therefore expensive, thermoform ⁇ ing of polypropylene alone.
  • plastics that do not bond to each other can be used in place of the polystyrene and polypropy ⁇ lene.
  • one of the plastic layers could be a thin separator layer which would be used for scrap after separating the thermoformed objects from each other.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Laminated Bodies (AREA)
  • Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)

Abstract

A process of making thermoformed plastic objects (12, 14) comprising coextruding a multilayered sheet (36) having adjacent layers of plastics that do not bond together during coextrusion, thermoforming the multilayered sheet (36), and separating individual thermoformed objects (12, 14) of different layers.

Description

THERMOFORMING COEXTRUDED PLASTIC SHEETS Field of the Invention The invention relates to preparing objects thermoformed from p astic sheets.
Background of the Invention Plastic sheets are often produced by appara¬ tus in which plastic material is heated and sup¬ plied under pressure to an extrusion die. The sheets can then be thermoformed to a desired shape, and individual objects can be trimmed from the thermoformed sheet.
Summary of the Invention In general the invention features coextruding a multilayered sheet having adjacent layers of plastics that do not bond to each other during co¬ extrusion, thermoforming the multilayered sheet, and separating individual thermoformed objects of different layers. With such a method,' the produc¬ tivity of the extrusion, thermoforming, and trim¬ ming apparatus is multiplied by the number of layers in the sheet.
In preferred embodiments one of the plastics in the multilayered sheet is polystyrene and another plastic is polypropylene; in some preferred embodiments one plastic is for a separator layer between plastic layers for the thermoformed objects, and in other preferred embodiments the thermoformed objects are made from more than one of the plastics of the layers of the multilayered sheet. The thermoforming of the multilayered sheet with poly¬ propylene and polystyrene layers is faster. than the slow, and therefore expensive, thermoforming of polypropylene alone- Description of the Preferred Embodiment
The preferred embodiment of the invention will now be described after first describing the draw¬ ing, which is a diagrammatic view of a process of manufacturing plastic objects according to the in¬ vention.
Referring to the drawing, there is shown ap¬ paratus 10 for manufacturing polypropylene bowls 12 and polystyrene bowls 14.
Two heated containers 16, 18 serve as sources of the polystyrene (70% crystal styrene and' 30% rub¬ ber modifying plastomer sold by Phillips Chemical Company under the trade designation Solprene 416P, a block polymer having a butadiene/styrene ratio of 70/30, a molecular weight of 140 M, a density of 0.94, and a melt flow index of 2 decigrams/ in) , and polypropylene- (available from Rexene Company, Paramus, New Jersey, and having a meltr flow index of 4 decigrams/ in) , respectively.
Conduits 20, 22, 24, 26, 28 supply the heated materials to coextrusion block' 30. There the ma¬ terials merge together to form under pressure a unitary, five-layer thick stream' 32 of generally circular cross section. Stream' 32 passes into extrusion die' 34 "(e.g. , Welex standard 54" flex- lip die) for extrusion into continuous sheet' 36. Sheet' 36 then passes through a series of chill rolls 38.
The sheet, after coextrusion, may then be thermoformed into bowls or wound into spools (not shown) for storage and later themoforming.
To process sheet' 36 into bowls, the sheet is passed through conventional thermoforming apparatus 40 (the vacuum forming type well known in the art) ,* which impresses the bowl shape.
After thermoforming, the shaped sheet 42 passes through trim press 44, in which the indivi¬ dual bowls 12 and 14 are trimmed. Because the polypropylene and polystyrene of bowls 12, 14, respectively, do not bond to each other during coextrusion or thermoforming, bowls 12, 14 can be easily separated from each other. The simultaneous coextruding of five sheets and thermoforming and trimming of five bowls act to increase the produc¬ tivity of the coextrusion, thermoforming, and trimming apparatus. by a factor of five. Also, the thermoforming of the five-layer sheet is faster than the slow, and therefore expensive, thermoform¬ ing of polypropylene alone.
Other Embodiments
Other embodiments of the invention are within the scope of the appended claims. For example, other plastics that do not bond to each other can be used in place of the polystyrene and polypropy¬ lene. Also, one of the plastic layers could be a thin separator layer which would be used for scrap after separating the thermoformed objects from each other.
^ . , .. :
Figure imgf000005_0001

Claims

Claims 1. A process of making thermoformed plastic objects comprising coextruding a multilayered sheet having adjacent layers of plastics that do not bond to¬ gether during coextrusion, thermoforming said multilayered sheet, and separating individual thermoformed objects of different layers.
2.. The process of claim 1 wherein said multilayered sheet is made of layers of polystyrene and poly¬ propylene.
3. The process of claim 1 wherein one said plastic is for a separator layer between layers for said objects.
The process of claim 1 wherein said thermoformed objects are made of more than one of the plastics of the layers of said multilayered sheet.
PCT/US1983/000158 1982-02-04 1983-02-04 Thermoforming coextruded plastic sheets WO1983002747A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US34593882A 1982-02-04 1982-02-04
US345,938820204 1982-02-04

Publications (1)

Publication Number Publication Date
WO1983002747A1 true WO1983002747A1 (en) 1983-08-18

Family

ID=23357183

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1983/000158 WO1983002747A1 (en) 1982-02-04 1983-02-04 Thermoforming coextruded plastic sheets

Country Status (3)

Country Link
EP (1) EP0101500A1 (en)
CA (1) CA1198562A (en)
WO (1) WO1983002747A1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2541628A1 (en) * 1983-02-25 1984-08-31 Roquette Freres Improved method and installation for manufacturing corrugated cardboard
US4657151A (en) * 1984-04-12 1987-04-14 Baxter Travenol Laboratories, Inc. Container such as a nursing container, with flexible liner
DE4101106A1 (en) * 1991-01-16 1992-07-23 Krauss Maffei Ag METHOD AND DEVICE FOR PRODUCING LAMINATED MOLDED PARTS
ES2049576A2 (en) * 1991-06-28 1994-04-16 Suprametal S A Identification sign manufacturing procedure and resulting product
GB2284569A (en) * 1993-12-08 1995-06-14 Rolls Royce Plc Manufacture of similarly shaped components
US10618610B2 (en) 2017-05-11 2020-04-14 Vista Outdoor Operations Llc Watersport boards and methods for forming the same

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2270185A (en) * 1940-08-15 1942-01-13 Dow Chemical Co Simultaneous manufacture of containers and closures
US3322870A (en) * 1965-04-06 1967-05-30 Union Carbide Corp Method of producing clear, crystalline, high-gloss thermoplastic film
US3494993A (en) * 1968-01-29 1970-02-10 Dow Chemical Co Extrusion of wide thermoplastic film and sheet
US3880691A (en) * 1971-03-23 1975-04-29 Pannenbecker H Process for producing film and sheet materials from thermoplastic materials having hot tack by the blown film process and the film and sheet materials thereby obtained
US3971866A (en) * 1974-06-07 1976-07-27 Minnesota Mining And Manufacturing Company Thermoformable release liner
US3977153A (en) * 1970-11-06 1976-08-31 The Dow Chemical Company Container for food products and method for making same
US4048428A (en) * 1961-12-05 1977-09-13 W. R. Grace & Co. Method for preparing a film of vinylidene chloride polymer

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2270185A (en) * 1940-08-15 1942-01-13 Dow Chemical Co Simultaneous manufacture of containers and closures
US4048428A (en) * 1961-12-05 1977-09-13 W. R. Grace & Co. Method for preparing a film of vinylidene chloride polymer
US3322870A (en) * 1965-04-06 1967-05-30 Union Carbide Corp Method of producing clear, crystalline, high-gloss thermoplastic film
US3494993A (en) * 1968-01-29 1970-02-10 Dow Chemical Co Extrusion of wide thermoplastic film and sheet
US3977153A (en) * 1970-11-06 1976-08-31 The Dow Chemical Company Container for food products and method for making same
US3880691A (en) * 1971-03-23 1975-04-29 Pannenbecker H Process for producing film and sheet materials from thermoplastic materials having hot tack by the blown film process and the film and sheet materials thereby obtained
US3971866A (en) * 1974-06-07 1976-07-27 Minnesota Mining And Manufacturing Company Thermoformable release liner

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2541628A1 (en) * 1983-02-25 1984-08-31 Roquette Freres Improved method and installation for manufacturing corrugated cardboard
US4657151A (en) * 1984-04-12 1987-04-14 Baxter Travenol Laboratories, Inc. Container such as a nursing container, with flexible liner
DE4101106A1 (en) * 1991-01-16 1992-07-23 Krauss Maffei Ag METHOD AND DEVICE FOR PRODUCING LAMINATED MOLDED PARTS
ES2049576A2 (en) * 1991-06-28 1994-04-16 Suprametal S A Identification sign manufacturing procedure and resulting product
GB2284569A (en) * 1993-12-08 1995-06-14 Rolls Royce Plc Manufacture of similarly shaped components
US10618610B2 (en) 2017-05-11 2020-04-14 Vista Outdoor Operations Llc Watersport boards and methods for forming the same

Also Published As

Publication number Publication date
CA1198562A (en) 1985-12-31
EP0101500A1 (en) 1984-02-29

Similar Documents

Publication Publication Date Title
US4440824A (en) Thermoformable coextruded multilayered structure
US4430288A (en) Making coextruded sheets and containers
US5405667A (en) Plastic container with multilayer label applied by in-mold labeling
US4402889A (en) Making sheet with moisture barrier properties coextruded from scrap materials
US3448183A (en) Method for the preparation of multilayer film
US3959432A (en) Coextrusion process
US4410587A (en) Co-extruded fusible net
US4100237A (en) Co-extrusion of ABS/polystyrene multiple-layered sheeting
EP0503065A4 (en) Process for producing laminate film
US4551365A (en) Rigid coextruded sheet and container
JPH04506195A (en) Foam core recycled multilayer sheet and its manufacturing method
US3968196A (en) Method of co-extrusion of polyvinylidene fluoride/polystyrene multiple-layered sheeting
EP0010895A1 (en) Method of making laminates of thermoplastic polymers by a single-channel coextrusion process and melt injector block for use therein
US4927690A (en) Thermoformable laminated packaging material
US4391863A (en) Peel resistant coextruded sheet
US3743459A (en) Apparatus for coextrusion of multilayer sheet or films
WO1983002747A1 (en) Thermoforming coextruded plastic sheets
US4051293A (en) Co-extrusion of polyvinylidene fluoride/polystyrene multiple-layered sheeting
EP0626667B1 (en) Application of labels to plastic containers
US3494993A (en) Extrusion of wide thermoplastic film and sheet
EP1147877A2 (en) Production of stretch plastic film
GB1205327A (en) Process for the production of laminates
CA1131868A (en) Process for producing plastic foil
JPH11512043A (en) METHOD AND APPARATUS FOR MANUFACTURING A PACKAGING PRODUCT OR A PORTION OF THE SAME AND A PACKAGING PRODUCT AND A PORTION THEREOF MANUFACTURED ACCORDING TO THE METHOD
JPH0753429B2 (en) Manufacturing method of composite container

Legal Events

Date Code Title Description
AK Designated states

Designated state(s): DE DK GB JP SE

AL Designated countries for regional patents

Designated state(s): AT BE CH DE FR GB LU NL SE