WO1987005856A1 - Procede et tete d'extrudeuse pour fabriquer des produits d'extrusion a partir de plastique fondu - Google Patents

Procede et tete d'extrudeuse pour fabriquer des produits d'extrusion a partir de plastique fondu Download PDF

Info

Publication number
WO1987005856A1
WO1987005856A1 PCT/FI1987/000047 FI8700047W WO8705856A1 WO 1987005856 A1 WO1987005856 A1 WO 1987005856A1 FI 8700047 W FI8700047 W FI 8700047W WO 8705856 A1 WO8705856 A1 WO 8705856A1
Authority
WO
WIPO (PCT)
Prior art keywords
rotor
rotors
extruder head
masses
vanes
Prior art date
Application number
PCT/FI1987/000047
Other languages
English (en)
Inventor
Kari Kirjavainen
Original Assignee
Kari Kirjavainen
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 Kari Kirjavainen filed Critical Kari Kirjavainen
Priority to KR1019870701142A priority Critical patent/KR880701172A/ko
Publication of WO1987005856A1 publication Critical patent/WO1987005856A1/fr

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
    • 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
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/362—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using static mixing devices
    • 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
    • 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
    • B29C48/14—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the particular extruding conditions, e.g. in a modified atmosphere or by using vibration
    • B29C48/147—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the particular extruding conditions, e.g. in a modified atmosphere or by using vibration after the die nozzle
    • B29C48/1472—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the particular extruding conditions, e.g. in a modified atmosphere or by using vibration after the die nozzle at the die nozzle exit 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
    • B29C48/16—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
    • B29C48/32—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles
    • B29C48/33—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles with parts rotatable relative to each other
    • 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
    • B29C48/32—Extrusion nozzles or dies with annular openings, e.g. for forming tubular articles
    • B29C48/335—Multiple annular extrusion nozzles in coaxial arrangement, e.g. for making multi-layered tubular articles
    • B29C48/336—Multiple annular extrusion nozzles in coaxial arrangement, e.g. for making multi-layered tubular articles the components merging one by one down streams in the die
    • B29C48/3363—Multiple annular extrusion nozzles in coaxial arrangement, e.g. for making multi-layered tubular articles the components merging one by one down streams in the die using a layered die, e.g. stacked discs
    • 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
    • B29C2791/00—Shaping characteristics in general
    • B29C2791/004—Shaping under special conditions
    • B29C2791/007—Using fluid under pressure
    • 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
    • B29C48/06—Rod-shaped
    • 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

Definitions

  • the additives which are either premixed in the moulding compounds or introduced during the extrusion phase by pumping, have a tendency - due to differences in pressure, speed and temperature gradients - to be separated from the mass and deposited on the surfaces of the mass flow channels.
  • the product shows stripes or seams along the lines where the components were merged.
  • the additives are usually pumped into mixer units incorporated in the extruder machine, the flow components being passed from the mixer units into the mass distributors.
  • the method of the invention employs ring-shaped rotors sandwiched between plates placed on top of each other, the mass being introduced at the rotor periphery and spread on both sides of the rotor toward the circular inner edge of the rotor, from where it proceeds in a tubular formation into the extruder nozzles.
  • the rotors are rotated either by the kinetic energy of the moving mass or by an external force.
  • the various components of the mass are mixed in the narrow spaces between the rotors and the plates, the mixed mass being thus directly output as a tubular flow, obviating the need for merging separate flow components. Therefore, the product is free of seams and stripes and has uniform thickness as well as a centric structure.
  • Figure 1 represents a cross-section of a three-layer embodiment of the extruder head of the invention.
  • Figure 2 represents the extruder head of figure 1 in lateral view.
  • Figure 3 represents a rotor as used in the extruder head.
  • Figure 4 represents a supply channel arrangement that may be used instead of that in figure 2.
  • Figure 5 represents another embodiment of the extruder head of the invention in lateral view.
  • the masses are supplied via the channels 8 provided between the plates 1a-1d to the peripheries of the rotors 2a-2c.
  • the plastic mass may be fed in by means of the presses used for melting and pressurizing the plastic materials; the other substances may be supplied e.g. by means of geared pumps.
  • the masses proceed into the input slit 9 and further into the bearing groove 10, from where they are introduced into the narrow spaces between the rotors and the plates, where the various mass components are mixed and passed further towards the central openings of the rotors.
  • the masses flowing from each side of the rotor are merged at the edge of the opening, they form a two-layer tubular flow, which is directed into the nozzles 3. using e.g.
  • a device consisting of four plates 1a-1d and three rotors 2a-2c. With such a device it is possible to produce tubular structures consisting of as many as six layers, depending on the materials pumped into the supply channels.
  • Channel 5 is used for the input of liquids and gases.
  • Figure 2 shows a lateral view of an extruder head as provided by the invention, comprising the plates 1, provided with vanes 6 (corresponding to the guide vanes of a radial turbine) attached to the rotor chamber surfaces, the rotors 2, provided with vanes 7 (corresponding to the runner vanes of a radial turbine) arranged in a converse angle, the channel system 4 for the supply of plastic mass and a channel 5 for the supply of additives.
  • the rotors shown in the figure rotate freely with the flow of the plastic mass at a speed corresponding to the speed of the mass flow.
  • the vanes 6,7 attached to the plates 1 and the rotors 2 effectively mix the masses supplied into the rotor spaces and cause them to move toward the central openings of the rotors.
  • the drawings do not show the auxiliary devices needed for purposes like heating, mounting etc., which are irrelevant to the principle of the invention.
  • Figure 3 shows the structure of the rotor 2 in greater detail.
  • the groove 11 at the rotor periphery is for the bearing balls supporting the rotor.
  • Figure 4 shows an alternative supply channel arrangement, in which the supply channel 12 forks into two branches directly communicating with the input slit 9 so that the supply pressure is evenly distributed over the whole periphery of the rotor.
  • Figure 5 shows an embodiment of the invention in which the rotors are driven by means of gears 14, which are attached to the shafts 13.
  • the rotor periphery must be provided with a gear track instead of the groove shown in figure 3.
  • This solution may be applied in cases when for some reason the mass flow does not impart a sufficiently high or low speed to the rotor to achieve the desired result. This applies to cases when e.g. the temperature or the degree of treatment or mixing of the plastic mass is to be changed by changing the speed of rotation of the rotors.
  • the method of the invention can be used in a wide variety of applications in the plastic industry and the manufacture of extrusion products in general, to mix together different materials, whether liquid, melted, pastelike, gaseous etc., in order to produce rotationally symmetric structures consisting of several layers, the number of which may vary. It is also possible to pump in the same material via all the supply channels. In this case, the desired additives may be supplied to the desired rotors or just one side of the rotor to produce different layer structures. Further, the number of plates 1 and rotors 2 can easily be increased, since this does not involve increased requirements regarding resistance to pressure and since all the rotors can be driven by the same power transmission shafts.
  • the geared pumps used for supplying additives can also be integrated between the plates 1, and so can the screw extrusion devices used for supplying plastic materials.
  • the latter devices may be very small and rotate at high speeds, since the final plasticity of the mass is achieved by means of the rotors 2 and since the supply channels can also be utilized to raise the mass temperature to the desired level.
  • the frictional heat can be controlled to regulate the final temperature of the mass. In this way, a system is provided in which the thermal time constants are very short and the mass is of uniform quality in the thermal respect as well.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)

Abstract

Des produits d'extrusion, tels que des câbles, des conduites, des films soufflés etc. constitués de plusieurs couches d'un matériau sont généralement fabriqués en utilisant des ajutages à plusieurs couches, dans lesquels les masses du matériau sont divisées en plusieurs composantes d'écoulement, lesquelles sont ensuite à nouveau fondues, afin de produire une structure tubulaire. L'inconvénient de ce procédé est que des saillies inutiles et des rayures risquent d'apparaître à l'endroit de fusion des composantes d'écoulement. Dans le procédé d'extrusion de la présente invention, les masses en écoulement sont homogénisées par des rotors tournant entre des plaques placées les unes sur les autres, les masses de plastique étant introduites dans les espaces des rotors à partir des périphéries des rotors puis acheminées vers les bords internes circulaires des rotors d'où elles se dirigent ensuite en un écoulement tubulaire dans les ajutages. Les matériaux utilisés dans ledit procédé de fabrication, tels que des plastiques, des colorants, des générateurs de mousse, des gaz, des agents de vulcanisation et d'autres substances chimiques, sont appliqués aux périphéries des rotors et mélangés par la rotation des rotors, le résultat étant un mélange homogène et un produit tubulaire de qualité uniforme.
PCT/FI1987/000047 1986-04-04 1987-04-03 Procede et tete d'extrudeuse pour fabriquer des produits d'extrusion a partir de plastique fondu WO1987005856A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1019870701142A KR880701172A (ko) 1986-04-04 1987-04-03 가소성 용융물질의 압출물 제조방법과 그 장치

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI861457A FI79802C (fi) 1986-04-04 1986-04-04 Foerfarande och presshuvud foer framstaellning av en roerformad extrusionsprodukt ur smaelt plastmassa.
FI861457 1986-04-04

Publications (1)

Publication Number Publication Date
WO1987005856A1 true WO1987005856A1 (fr) 1987-10-08

Family

ID=8522415

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/FI1987/000047 WO1987005856A1 (fr) 1986-04-04 1987-04-03 Procede et tete d'extrudeuse pour fabriquer des produits d'extrusion a partir de plastique fondu

Country Status (7)

Country Link
EP (1) EP0310602A1 (fr)
JP (1) JPH01501925A (fr)
KR (1) KR880701172A (fr)
CN (1) CN87102620A (fr)
ES (1) ES2004134A6 (fr)
FI (1) FI79802C (fr)
WO (1) WO1987005856A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0703066A1 (fr) * 1994-09-21 1996-03-27 Kureha Kagaku Kogyo Kabushiki Kaisha Produit polymérique stratifié oblique
WO1997001428A1 (fr) * 1995-06-26 1997-01-16 Conenor Oy Appareil a extruder et procede d'orientation de matiere plastique dans lequel il est utilise

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9132578B2 (en) * 2011-11-29 2015-09-15 Corning Incorporated Apparatus and method for skinning articles
US9670809B2 (en) 2011-11-29 2017-06-06 Corning Incorporated Apparatus and method for skinning articles
US10611051B2 (en) 2013-10-15 2020-04-07 Corning Incorporated Systems and methods for skinning articles
US9239296B2 (en) 2014-03-18 2016-01-19 Corning Incorporated Skinning of ceramic honeycomb bodies

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3490097A (en) * 1968-02-16 1970-01-20 Dow Chemical Co Flighted extruder
CH502889A (fr) * 1968-11-28 1971-02-15 Pechiney Saint Gobain Extrudeuse à deux plateaux
US3609807A (en) * 1968-09-02 1971-10-05 Sidel Sa Rotary plate extruding machine
DE1554858A1 (de) * 1965-05-19 1971-12-16 Ugine Kuhlmann Strangpresse mit scheibenfoermigem Rotor zur Verarbeitung von Hochpolymeren
US3784339A (en) * 1970-05-29 1974-01-08 Anger Kunststoff Disk extruder

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1554858A1 (de) * 1965-05-19 1971-12-16 Ugine Kuhlmann Strangpresse mit scheibenfoermigem Rotor zur Verarbeitung von Hochpolymeren
US3490097A (en) * 1968-02-16 1970-01-20 Dow Chemical Co Flighted extruder
US3609807A (en) * 1968-09-02 1971-10-05 Sidel Sa Rotary plate extruding machine
CH502889A (fr) * 1968-11-28 1971-02-15 Pechiney Saint Gobain Extrudeuse à deux plateaux
US3784339A (en) * 1970-05-29 1974-01-08 Anger Kunststoff Disk extruder

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0703066A1 (fr) * 1994-09-21 1996-03-27 Kureha Kagaku Kogyo Kabushiki Kaisha Produit polymérique stratifié oblique
US5633065A (en) * 1994-09-21 1997-05-27 Kureha Kagaku Kogyo Kabushiki Kaisha Laminate resin product
WO1997001428A1 (fr) * 1995-06-26 1997-01-16 Conenor Oy Appareil a extruder et procede d'orientation de matiere plastique dans lequel il est utilise
CN1058214C (zh) * 1995-06-26 2000-11-08 奈克斯特罗姆·霍尔丁公司 挤压设备和利用挤压设备使塑料取向的方法
US6197239B1 (en) 1995-06-26 2001-03-06 Nextrom Holding S.A. Extrusion apparatus and method for orienting plastic material by using an extrusion apparatus

Also Published As

Publication number Publication date
FI79802B (fi) 1989-11-30
JPH01501925A (ja) 1989-07-06
FI861457A (fi) 1987-10-05
FI79802C (fi) 1990-03-12
KR880701172A (ko) 1988-07-26
FI861457A0 (fi) 1986-04-04
ES2004134A6 (es) 1988-12-01
EP0310602A1 (fr) 1989-04-12
CN87102620A (zh) 1987-10-14

Similar Documents

Publication Publication Date Title
US2469999A (en) Mixing head for extrusion machines
JP3097760B2 (ja) 多軸型薄層反応装置
JPH0643055B2 (ja) 溶融材料の部分流の形成・再配列方法及び装置
US7513766B2 (en) Extrusion apparatus having a driven feed segment
US20030048694A1 (en) Material mixing device and method
JPH04276407A (ja) 自動車タイヤ、駆動ベルト、コンベヤベルト並びに工業ゴム製品のためのゴム基礎混合物とゴム仕上げ混合物を１台の混合装置で１段階的にかつ連続的に製造するための方法と装置
EP0234889A2 (fr) Appareil et procédé pour traiter un matériau visqueux
US4231666A (en) Mixing apparatus
JP2011500392A (ja) ポリマー材料の加工装置と方法
US4082488A (en) Apparatus for the extrusion of temperature sensitive thermoplastics
US4514090A (en) Apparatus for processing viscous substances or substances which become viscous through processing
WO1987005856A1 (fr) Procede et tete d'extrudeuse pour fabriquer des produits d'extrusion a partir de plastique fondu
US4749279A (en) Modular mixing apparatus for extruded material including rotary for processing modules having variable speed independent drive means
US4313909A (en) Method and an apparatus for producing a reaction mixture for forming solid or cellular substances from flowable reactants and optionally fillers
US3807703A (en) Mixer-emulsators
US3677863A (en) Dies for producing multi-layer tubes or films
JPH04229222A (ja) 熱互変性液晶物質から成形品を製造するための方法および装置、およびその方法により製造した成形品
US3778036A (en) Device for plasticizing and homogenizing viscous masses
US4906102A (en) Apparatus for mixing thermoplastified synthetic resins
WO2009051279A1 (fr) Extrudeuse et procédé pour préparer un mélange de polymère et de diluant
US2948922A (en) Screw conveyor
US4330215A (en) Mixing device
US20070183254A1 (en) Infinitely variable shear mixer apparatus
KR20010015786A (ko) 중합체융해물을 믹싱하고 운반하는 장치
CN1085584C (zh) 具有混合装置和可调剪切效果的挤压头

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP KR SU US

AL Designated countries for regional patents

Kind code of ref document: A1

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

WWE Wipo information: entry into national phase

Ref document number: 1987902520

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1987902520

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1987902520

Country of ref document: EP