GB1444757A - Process and apparatus for preparing polymeric film - Google Patents

Process and apparatus for preparing polymeric film

Info

Publication number
GB1444757A
GB1444757A GB3845873A GB3845873A GB1444757A GB 1444757 A GB1444757 A GB 1444757A GB 3845873 A GB3845873 A GB 3845873A GB 3845873 A GB3845873 A GB 3845873A GB 1444757 A GB1444757 A GB 1444757A
Authority
GB
United Kingdom
Prior art keywords
thickness
width
web
drum
computer
Prior art date
Legal status (The legal status 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 status listed.)
Expired
Application number
GB3845873A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EIDP Inc
Original Assignee
EI Du Pont de Nemours and Co
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
Priority claimed from US00280890A external-priority patent/US3819775A/en
Application filed by EI Du Pont de Nemours and Co filed Critical EI Du Pont de Nemours and Co
Publication of GB1444757A publication Critical patent/GB1444757A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D5/00—Control of dimensions of material
    • G05D5/02—Control of dimensions of material of thickness, e.g. of rolled material
    • G05D5/03—Control of dimensions of material of thickness, e.g. of rolled material characterised by the use of electric means
    • 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
    • B29C48/25—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
    • B29C48/31—Extrusion nozzles or dies having a wide opening, e.g. for forming sheets being adjustable, i.e. having adjustable exit sections
    • B29C48/313—Extrusion nozzles or dies having a wide opening, e.g. for forming sheets being adjustable, i.e. having adjustable exit sections by positioning the die lips
    • 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
    • B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
    • B29C48/86—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the nozzle zone
    • 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
    • B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
    • B29C48/86—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the nozzle zone
    • B29C48/865—Heating
    • 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
    • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
    • B29C48/911—Cooling
    • B29C48/9135—Cooling of flat articles, e.g. using specially adapted supporting means
    • B29C48/914—Cooling of flat articles, e.g. using specially adapted supporting means cooling drums
    • 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
    • B29C48/88—Thermal treatment of the stream of extruded material, e.g. cooling
    • B29C48/911—Cooling
    • B29C48/9135—Cooling of flat articles, e.g. using specially adapted supporting means
    • B29C48/915—Cooling of flat articles, e.g. using specially adapted supporting means with means for improving the adhesion to the supporting means
    • B29C48/9165—Electrostatic pinning
    • 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
    • B29C48/92—Measuring, controlling or regulating
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92009—Measured parameter
    • B29C2948/92114—Dimensions
    • B29C2948/92152—Thickness
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92009—Measured parameter
    • B29C2948/92114—Dimensions
    • B29C2948/92171—Distortion, shrinkage, dilatation, swell or warpage
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92009—Measured parameter
    • B29C2948/92209—Temperature
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92323—Location or phase of measurement
    • B29C2948/92361—Extrusion unit
    • B29C2948/92409—Die; Nozzle zone
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92323—Location or phase of measurement
    • B29C2948/92447—Moulded article
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92504—Controlled parameter
    • B29C2948/92523—Force; Tension
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92504—Controlled parameter
    • B29C2948/92609—Dimensions
    • B29C2948/92647—Thickness
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92504—Controlled parameter
    • B29C2948/92609—Dimensions
    • B29C2948/92666—Distortion, shrinkage, dilatation, swell or warpage
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92504—Controlled parameter
    • B29C2948/92695—Viscosity; Melt flow index [MFI]; Molecular weight
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92504—Controlled parameter
    • B29C2948/92704—Temperature
    • 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
    • B29C2948/00—Indexing scheme relating to extrusion moulding
    • B29C2948/92—Measuring, controlling or regulating
    • B29C2948/92819—Location or phase of control
    • B29C2948/92857—Extrusion unit
    • B29C2948/92904—Die; Nozzle zone

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Manufacturing & Machinery (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)

Abstract

1444757 Controlling thickness of extruded film E I DU PONT DE NEMOURS & CO 14 Aug 1973 [15 Aug 1972 (2)] 38458/73 Headings B5A and B5B [Also in Division G3] Thickness of an extruded flat thermoplastics film is regulated across its width by independent manual or automatic temperature control of one or more thermally isolated segments extending across the width of the die. The film is extruded on to a quenching surface comprising a stainless steel conveyer band or rotary drum, and then reheated and transversely and longitudinally stretched. In the described embodiment Fig. 2, the temperature of the thermoplastics in the outlet passage 32 of the die 10 is controlled to regulate its extrusion rate across the width of the passage by segments 13 each provided with a resistance heater and temperature sensor 15, and thermally insulated by an air gap comprising a slot 41 terminating upstream at a cylindrical bore 43. The extruding web W may be pinned across its width to a quenching drum 40, either by fluid from a conduit spaced across the drum W, or electrostatically by an electrode wire across the width of the web in combination with earthing of the drum. For manual control of the die segments, the effect of each segment 13 is calibrated, and the heat input to each segment manually adjusted according to the thickness recorded by a betaray scanner 17, Fig. 1, which traverses the web and records thickness variations which are displayed on a cathode ray tube. From automatic control of the web thickness, Fig. 1, a digital computer 18 is connected, through analog-to-digital converters 19a and 19b to the output of the temperature sensors 15 and the beta-ray scanner 17. Computer 18 compares the input data with a programmed thickness profile and determines the amount of electrical power to be supplied to the heating elements to obtain the desired thickness profile. The computer 18 distributes the power through a supply interface 16. Preferably, the computer initially distibutes power at a uniform level to all heaters, and then effects any necessary correction by preferably reducing the power input to a selected segment 13. The thermoplastics preferably comprises polyester, but may also comprise polypropylene, polyethylene or polyamides.
GB3845873A 1972-08-15 1973-08-14 Process and apparatus for preparing polymeric film Expired GB1444757A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US28088872A 1972-08-15 1972-08-15
US00280890A US3819775A (en) 1972-08-15 1972-08-15 Method of making polymeric film

Publications (1)

Publication Number Publication Date
GB1444757A true GB1444757A (en) 1976-08-04

Family

ID=26960586

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3845873A Expired GB1444757A (en) 1972-08-15 1973-08-14 Process and apparatus for preparing polymeric film

Country Status (6)

Country Link
BE (1) BE803611A (en)
DE (1) DE2341127C2 (en)
FR (1) FR2196231B1 (en)
GB (1) GB1444757A (en)
LU (1) LU68236A1 (en)
NL (1) NL182944C (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0260608A1 (en) * 1986-09-16 1988-03-23 WindmÀ¶ller & Hölscher Process for preparing bobbins from extruded webs
EP1834753A2 (en) * 2006-03-15 2007-09-19 Breyer GmbH Maschinenfabrik Method for operating extrusion plants for extruding thermoplastics
WO2008107169A1 (en) * 2007-03-07 2008-09-12 Breyer Gmbh Maschinenfabrik Extrusion die for producing hollow profiles
CN111688153A (en) * 2019-03-15 2020-09-22 株式会社日本制钢所 Resin film manufacturing apparatus and resin film manufacturing method
WO2023037260A1 (en) * 2021-09-08 2023-03-16 Syncro S.R.L. Method and apparatus for adjusting the thickness of a plastic film produced by cast extrusion process

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2424127A1 (en) * 1978-04-28 1979-11-23 Fabrications Et Heater power control of concentricity of extruded plastic sheathing - by adjusting flow rates on opposite sides of the die head
DE3006566A1 (en) * 1980-02-21 1981-08-27 Windmöller & Hölscher, 4540 Lengerich METHOD FOR REGULATING THE FILM THICKNESS OF FLAT FILMS PRODUCED IN FLAT FILM EXTRUSION PLANTS
DE3503721C2 (en) * 1985-02-05 1993-12-16 Hoechst Ag Wide slot die for extruding a thermoplastic
DE68907907T2 (en) * 1989-10-17 1993-11-11 Tomi Machinery Mfg Co Ltd Synthetic resin film, method and device for making the film thickness uniform during molding.

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3341388A (en) * 1964-05-20 1967-09-12 Phillips Petroleum Co Method and apparatus for the uniform extruding of thermoplastic film
LU57522A1 (en) * 1967-12-13 1970-06-11
NL7014565A (en) * 1970-10-05 1972-04-07
US3761553A (en) * 1971-06-28 1973-09-25 Celanese Corp Method for producing uniform drawn films

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0260608A1 (en) * 1986-09-16 1988-03-23 WindmÀ¶ller & Hölscher Process for preparing bobbins from extruded webs
EP1834753A2 (en) * 2006-03-15 2007-09-19 Breyer GmbH Maschinenfabrik Method for operating extrusion plants for extruding thermoplastics
EP1834753A3 (en) * 2006-03-15 2008-06-25 Breyer GmbH Maschinenfabrik Method for operating extrusion plants for extruding thermoplastics
WO2008107169A1 (en) * 2007-03-07 2008-09-12 Breyer Gmbh Maschinenfabrik Extrusion die for producing hollow profiles
CN111688153A (en) * 2019-03-15 2020-09-22 株式会社日本制钢所 Resin film manufacturing apparatus and resin film manufacturing method
CN111688153B (en) * 2019-03-15 2023-09-01 株式会社日本制钢所 Resin film manufacturing apparatus and resin film manufacturing method
WO2023037260A1 (en) * 2021-09-08 2023-03-16 Syncro S.R.L. Method and apparatus for adjusting the thickness of a plastic film produced by cast extrusion process

Also Published As

Publication number Publication date
NL182944B (en) 1988-01-18
FR2196231A1 (en) 1974-03-15
DE2341127C2 (en) 1984-03-22
NL182944C (en) 1988-06-16
NL7311179A (en) 1974-02-19
BE803611A (en) 1974-02-14
FR2196231B1 (en) 1978-01-27
LU68236A1 (en) 1974-02-21
DE2341127A1 (en) 1974-02-28

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PE20 Patent expired after termination of 20 years

Effective date: 19930813