DE2647555A1 - Mfr. of tubular film of partly crystalline thermoplastics - by extruding above crystallite melting temp., inflating and sharply cooling - Google Patents

Mfr. of tubular film of partly crystalline thermoplastics - by extruding above crystallite melting temp., inflating and sharply cooling

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Publication number
DE2647555A1
DE2647555A1 DE19762647555 DE2647555A DE2647555A1 DE 2647555 A1 DE2647555 A1 DE 2647555A1 DE 19762647555 DE19762647555 DE 19762647555 DE 2647555 A DE2647555 A DE 2647555A DE 2647555 A1 DE2647555 A1 DE 2647555A1
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DE
Germany
Prior art keywords
tubular film
film
mfr
inflating
crystallite melting
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.)
Pending
Application number
DE19762647555
Other languages
German (de)
Inventor
Auf Nichtnennung Antrag
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to DE19762647555 priority Critical patent/DE2647555A1/en
Publication of DE2647555A1 publication Critical patent/DE2647555A1/en
Pending legal-status Critical Current

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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
    • 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
    • B29C48/90—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article
    • B29C48/901—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article of hollow bodies
    • 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
    • B29C48/09—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels
    • B29C48/10—Articles with cross-sections having partially or fully enclosed cavities, e.g. pipes or channels flexible, e.g. blown foils
    • 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
    • B29C48/9175—Cooling of flat articles, e.g. using specially adapted supporting means by interposing a fluid layer between the supporting means and the flat 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
    • 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
    • B29C48/90—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article
    • B29C48/901—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article of hollow bodies
    • B29C48/903—Thermal treatment of the stream of extruded material, e.g. cooling with calibration or sizing, i.e. combined with fixing or setting of the final dimensions of the extruded article of hollow bodies externally
    • 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
    • B29C48/9115—Cooling of hollow articles
    • B29C48/912—Cooling of hollow articles of tubular films
    • B29C48/913—Cooling of hollow articles of tubular films externally

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Shaping By String And By Release Of Stress In Plastics And The Like (AREA)

Abstract

Mfr. of tubular film of partly crystalline thermoplastics comprises (a) extruding the plastics at 5-170 degrees C above its crystalline m.p.; (b) inflating the resulting tube to 1 1-4 times its initial dia.; and (c) cooling the resulting tubular film, immediately after inflation, to at least 30 degrees C below the crystallite m.p. of the thermoplastics. A cooling installation is used comprising cooled rollers arranged like a "crown" and surrounding the film, which are in tangential contact with the film. The rollers are rotated by virtue of the sliding friction between them and the moving film. The process is esp. suitable for mfr. of tubular polypropylene film.

Description

Verfahren zum Herstellen von Schlauchfolien ausProcess for the production of tubular films

teilkristallinem thermoplastischen Kunststoff Die vorliegende Erfindung betrifft ein Verfahren zum Herstellen von Schlauchfolien aus teilkristallinem thermoplastischen Kunstst-off, wobei man (A) aus dem Kunststoff bei einer 5-170°C über dem Kristallitscbmelzpunkt des Kunststoffs liegenden Temperatur einen Primärschlauch extrudiert, (B) den Primärschlauch auf das 1,1-4-fache seines Durchmessers in die Schlauchfolie überführt und (c) die Schlauchfolie unmittelbar nach dem Aufblasen dann mittels einer Kühlvorrichtung auf eine wenigstens 30°C unter dem Kristallitschmelzpunkt des Kunststoffs liegende Temperatur bringt.partially crystalline thermoplastic material The present invention relates to a method for producing tubular films from partially crystalline thermoplastic Kunstst-off, whereby you (A) from the plastic at a 5-170 ° C above the crystallite melting point the temperature of the plastic, a primary tube is extruded, (B) the primary tube transferred to 1.1-4 times its diameter in the tubular film and (c) the Tubular film then immediately after inflation by means of a cooling device to a temperature at least 30 ° C below the crystallite melting point of the plastic Temperature brings.

Die Durchführung des oben beschriebenen Verfahrens ist gegenüber vergleichbarer anderer Verfahren mit einigen Vorteilen verbunden.The implementation of the method described above is more comparable other procedures have some advantages.

Insbesondere erlaubt dieses Verfahren nicht nur vertikal abwärts, sondern auch vertikal aufwärts hochtransparente Schlauchfolien herzustellen. Diesem Vorteil steht bei den bekannten Verfahren der genannten Art jedoch ein Nachteil gegenüber: Die bisher eingesetzten Vorrichtungen für die primäre Schlauchfolie sind technisch zu aufwendig oder sie arbeiten störanfällig und nicht wirtschaftlich.In particular, this method allows not only vertically downwards, but also to produce highly transparent tubular films vertically upwards. This one However, there is an advantage in the known methods of the type mentioned, but there is a disadvantage opposite: The devices previously used for the primary tubular film are technically too complex or they work prone to failure and not economically.

Der vorliegenden Erfindung lag die Aufgabe zugrunde, eine besondere Kühlvorrichtung aufzuzeigen, durch deren Einsatz im Rahmen der Durchführung des eingangs beschriebenen Verfahrens sich die geschilderten Nachteile vermeiden lassen. Es wurde gefunden, daß diese Aufgabe gelöst werden konnte mittel# in besonderer Weise ausgebildeten und speziell angeordneten Kühlvorrichtung.The present invention was based on the object of a special To show cooling devices, through their use in the context of the implementation of the The method described at the outset can avoid the disadvantages described. It was found that this object could be achieved by means of # in particular Way trained and specially arranged cooling device.

Gegenstand der vorliegenden Erfindung ist dementsprechend ein Verfahren zum Herstellen von Schlauchfolien aus teilkristallinem thermoplastischen Kunststoff, insbesondere Polypropylen (PP), wobei man (A) aus dem Kunststoff bei einer 5-1700C bei PP, insbesondere im Temperaturbereich von 55-90 0C über dem Kristallitschmelzpunkt des Klnststoffs liegenden Temperatur, einen Primärschlauch extrudiert, (B) den Primärschlauch durch Aufblasen auf das l,l-4fache seines Durchmessers in die Schlauchfolie überführt und (C) die Schlauchfolie unmittelbar nach dem Aufblasen einer Kühlvorrichtung auf eine wenigstens 30°C, bei PP insbesondere 120 C, unter dem Kristallitschmelzpunkt liegende Temperatur bringt. Das erfindungsgemäße Verfahren ist dadurch gekennzeichnet, daß mit einer Kühlvorrichtung gearbeitet wird, die ausgebildet ist als ein die Schlauchfolie umgebender Kranz gekühlter Rollen, die tangential in Berührung mit der Schlauchfolie stehen und n h durch deren Bewegung unter gleitender Reibung in Rotation gehalten werden.The present invention accordingly relates to a method for the production of tubular films made of semi-crystalline thermoplastic material, especially polypropylene (PP), where one (A) from the plastic at a 5-1700C in the case of PP, especially in the temperature range of 55-90 ° C. above the crystallite melting point the temperature of the plastic, extruded a primary tube, (B) the primary tube transferred into the tubular film by inflation to l, l-4 times its diameter and (C) the tubular film immediately after inflation of a cooling device at least 30 ° C, in the case of PP in particular 120 C, below the crystallite melting point brings lying temperature. The method according to the invention is characterized in that that a cooling device is used which is designed as a tubular film Surrounding ring of cooled rollers that are tangentially in contact with the tubular film stand and n h kept in rotation by their movement under sliding friction will.

Zu den Einzelheiten des erfindungsgemäßen Verfahrens ist folgendes zu bemerken: Das neue Verfahren kann -abgesehen von der erfindungsgemäßen Besonderheit- in einschlägiger üblicher Weise mittels einschlägig üblichen Vorrichtungen unter Einsatz der üblichen teilkristallinen tbrmoplastischen Kunststoffe durchgeführt werden.Regarding the details of the method according to the invention, the following is given to note: The new method can - apart from the special feature according to the invention - in the relevant customary manner by means of relevant customary devices under Use of the usual partially crystalline thermoplastic plastics carried out will.

Statt weiterer Ausführungen hierzu wird zur näheren Erläuterung auf die Literaturstellen JAPAN PLASTICS AGE 7 (1969) 8, 5.45-48 und auf die englische Patentschrift 972556 hingewiesen.Instead of further explanations, refer to for a more detailed explanation the references JAPAN PLASTICS AGE 7 (1969) 8, 5.45-48 and the English Patent 972556 pointed out.

Die Besonderheit des erfindungsgemäßen Verfahrens liegt in der Ausbildung und Anordnung der Kühlvorrichtung, die als Kranz gekühlter Rollen ausgebildet ist. Fig.l zeigt eine Ausbildung und Anordnung der Kühlvorrichtung mit Kühlmedien durchflossenen konkaven Rollen über dem Werkzeug. Die analoge Anordnung ist unter dem Werkzeug zu verstehen. Zweckmäßig ist es, wenn zwei solche Kränze im minimal möglichen Abstand, lückig versetzt, übereinander angeordnet sind, da hierdurch die Transparenz einheitlicher ist. Eine besondere Ausgestaltung ist die Erzeugung nicht schockartig gekühlter Folienstreifen durch teilweises \&eg lassen von gekühlten Rollen am Schlauchumfang. Fig.2 stellt eine andere Ausbildung und Anordnung der Kühlvorrichtung von Fig.l mit zusätzlicher Außenkühlung der konkaven Rollen oder nur mit Außenkühlung dar.The peculiarity of the method according to the invention lies in the training and arrangement of the cooling device, which is designed as a ring of cooled rollers. Fig.l shows a design and arrangement of the cooling device with cooling media flowing through it concave rollers over the tool. The same arrangement is under the tool to understand. It is useful if two such wreaths are at the minimum possible distance, are staggered with gaps, arranged one above the other, as this makes the transparency more uniform is. A special embodiment is the generation not shocking cooled film strips by partially leaving the cooled rolls on Hose circumference. 2 shows another design and arrangement of the cooling device from Fig.l with additional external cooling of the concave rollers or only with external cooling represent.

Die Rollenbreite B läßt sich aus der doppelten Liegebreite FB über den Schlauchhalbmesser 2 FB = DTI = 2#R'fl unter Zugrundelegung einer geringen Umfangsgeschwindigkeftsdiffernnz des Außen- und Innendurchmessers der konkaven Rolle von weniger als wobei B = Rollenbreite, R = Schlauchradius, x = Schlauchradiusreduzierung zur Ermittlung von B.The roll width B can be calculated from twice the lying width FB over the tube radius 2 FB = DTI = 2 # R'fl, based on a small circumferential speed difference of the outside and inside diameter of the concave roll of less than where B = roll width, R = hose radius, x = hose radius reduction to determine B.

Die Rollenanzahl n ergibt sich über die zur entsprechenden Rollen Da die Rollenanzahl n durch volle Çalzenbelegung des Schlauchumfangs ohne jeglichen Luftspalt bestimmt wird, ist zur Erzielung einheitlicher Transparenz mit der Kühlvorrichtung nach Fig.l eine Sicherheitsüberdeckung der gekühlten konkaven Rollen in hohem Maße wünschenswert, d.h. die Walzenanzahl n ist entsprechend zu erhöhen.The number of roles n results from the corresponding roles Since the number of rollers n is determined by full Çalzenbelocation of the hose circumference without any air gap, a safety covering of the cooled concave rollers is highly desirable in order to achieve uniform transparency with the cooling device according to Fig.l, ie the number of rollers n must be increased accordingly.

Ein typisches Beispiel für die Ausgestaltung. Bei doppelter Liegebreite FB= 1207 mm ergibt sich ein Schlauchhalbmesser R = 400 mm, eine Rollenbreite B 31 120 mm, eine Bogenlänge b = 118,5 rnni und damit eine Rollenanzahl n von 21,2, die sicherheitshalber bei einer Kühivorrichtung nach Fig»E auf 22-23 erhöht wird.A typical example of the design. With double the lying width FB = 1207 mm results in a hose radius R = 400 mm, a roll width B 31 120 mm, an arc length b = 118.5 rnni and thus a number of rolls n of 21.2, the to be on the safe side, it is increased to 22-23 in the case of a cooling device according to FIG.

Die Kühlung der Rollen kann mittelbar über die Achsen oder bei leichtem Lauf unmittelbar durch direkte Rollenkühlung nach geläufigen Verfahrenstechniken erfolgen.Bei den für die Kühlvorrichtung in Frage kommeneden metallischen Werkstoffen sind gute lirmeleitungBeigensthaften vorteilhaftThe rollers can be cooled indirectly via the axles or with light Run directly through direct roller cooling according to common process technologies The metallic materials that can be used for the cooling device Good conductors are inherently beneficial

Claims (1)

Patentanspruch Verfahren zum Herstellen von Schlauchfolien aus teilkristallinem thermoplastischen Kunststoff, wobei man (A) aus dem Kunststof bei einer 5 bis 1700 c über dem Kristallitschmelzpunkt des Kunststoffs liegenden Temperatur einen Primärschlauch extrudiert, (B) den Primärschlauch durch Aufblasen auf das 1,1 bis 4-fache seines Durchmessers in die Schlauchfolie überführt und (C) die Schlauchfolie unmittelbar nach dem Aufblasen dann mittels einer Kühivorrichtung auf eine wenigstens 300 c unter dem Kristallitschmelzpunkt des Kunststoffs liegende Temperatur bringt, dadurch gekennzeichnet, daß mit einer Kühlvorrichtung gearbeitet wird, die ausgebildet ist als ein die Schlauchfolie umgebender Kranz gekühlter Rollen, die tangential in Berührung mit der Schlauchfolie stehen und durch deren Bewegung unter gleitender Reibung in Rotation gehalten werden. Patent claim method for producing tubular films from partially crystalline thermoplastic plastic, whereby (A) from the plastic at a 5 to 1700 c above the crystallite melting point of the plastic a primary tube extruded, (B) the primary tube by inflating it to 1.1 to 4 times its Diameter into the tubular film and (C) the tubular film immediately after inflation then by means of a cooling device to at least 300 c brings the temperature below the crystallite melting point of the plastic, thereby characterized in that it is operated with a cooling device which is formed as a ring of cooled rollers surrounding the tubular film, which are in tangential contact stand with the tubular film and move it under sliding friction in Rotation are kept.
DE19762647555 1976-10-21 1976-10-21 Mfr. of tubular film of partly crystalline thermoplastics - by extruding above crystallite melting temp., inflating and sharply cooling Pending DE2647555A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE19762647555 DE2647555A1 (en) 1976-10-21 1976-10-21 Mfr. of tubular film of partly crystalline thermoplastics - by extruding above crystallite melting temp., inflating and sharply cooling

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19762647555 DE2647555A1 (en) 1976-10-21 1976-10-21 Mfr. of tubular film of partly crystalline thermoplastics - by extruding above crystallite melting temp., inflating and sharply cooling

Publications (1)

Publication Number Publication Date
DE2647555A1 true DE2647555A1 (en) 1978-04-27

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DE19762647555 Pending DE2647555A1 (en) 1976-10-21 1976-10-21 Mfr. of tubular film of partly crystalline thermoplastics - by extruding above crystallite melting temp., inflating and sharply cooling

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2951417A1 (en) * 1978-12-25 1980-07-03 Chisso Eng Co Ltd DEVICE FOR PRODUCING BIAXIAL STRETCHED TUBE-SHAPED FILMS
EP0056120A2 (en) * 1981-01-14 1982-07-21 BASF Aktiengesellschaft Method and apparatus for producing thermoplastic tubular films

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2951417A1 (en) * 1978-12-25 1980-07-03 Chisso Eng Co Ltd DEVICE FOR PRODUCING BIAXIAL STRETCHED TUBE-SHAPED FILMS
EP0056120A2 (en) * 1981-01-14 1982-07-21 BASF Aktiengesellschaft Method and apparatus for producing thermoplastic tubular films
EP0056120A3 (en) * 1981-01-14 1982-09-01 BASF Aktiengesellschaft Method and apparatus for producing thermoplastic tubular films

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