EP0953071A1 - Manufacture of elongate members - Google Patents

Manufacture of elongate members

Info

Publication number
EP0953071A1
EP0953071A1 EP98900898A EP98900898A EP0953071A1 EP 0953071 A1 EP0953071 A1 EP 0953071A1 EP 98900898 A EP98900898 A EP 98900898A EP 98900898 A EP98900898 A EP 98900898A EP 0953071 A1 EP0953071 A1 EP 0953071A1
Authority
EP
European Patent Office
Prior art keywords
elongate member
cross
polymer
acrylonitrile
melt
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.)
Withdrawn
Application number
EP98900898A
Other languages
German (de)
French (fr)
Inventor
David Mac Service
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.)
Acordis UK Ltd
Original Assignee
Acordis Fibres Holdings Ltd
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 Acordis Fibres Holdings Ltd filed Critical Acordis Fibres Holdings Ltd
Publication of EP0953071A1 publication Critical patent/EP0953071A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
    • C08J5/18—Manufacture of films or sheets
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F11/00—Chemical after-treatment of artificial filaments or the like during manufacture
    • D01F11/04—Chemical after-treatment of artificial filaments or the like during manufacture of synthetic polymers
    • D01F11/08—Chemical after-treatment of artificial filaments or the like during manufacture of synthetic polymers of macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
    • D01F6/02—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D01F6/18—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds from polymers of unsaturated nitriles, e.g. polyacrylonitrile, polyvinylidene cyanide
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F9/00—Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments
    • D01F9/08—Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments of inorganic material
    • D01F9/12—Carbon filaments; Apparatus specially adapted for the manufacture thereof
    • D01F9/14—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments
    • D01F9/20—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products
    • D01F9/21—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • D01F9/22—Carbon filaments; Apparatus specially adapted for the manufacture thereof by decomposition of organic filaments from polyaddition, polycondensation or polymerisation products from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds from polyacrylonitriles
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2333/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
    • C08J2333/18—Homopolymers or copolymers of nitriles
    • C08J2333/20—Homopolymers or copolymers of acrylonitrile

Definitions

  • This invention relates to the manufacture of elongate members based on acrylonitrile polymers and to their oxidation, carbonisation and graphitisation.
  • Acrylic polymers are defined as polymers which contain at least 85% by weight acrylonitrile monomer units.
  • Modacrylic polymers are defined as polymers which contain 40 to 85% by weight acrylonitrile monomer units.
  • Many acrylonitrile polymers, including a large proportion of acrylic polymers, are infusible and decompose without melting when they are heated.
  • Processes are known by which such polymers can be processed into elongate members, for example fibres, using wet- or dry-extrusion techniques. These involve the extrusion of a solution of the polymer in a suitable solvent into a coagulating bath or an evaporative atmosphere, respectively. Processes are also known whereby elongate members can be manufactured by extrusion of a plasticised acrylonitrile polymer under dry-spinning conditions, followed by removal of the plasticiser. Fusible acrylonitrile polymers are also known and are described for example in US-A-5 , 106 , 925 and US-A-5 , 286 , 828 (both Curatolo et al .
  • Such fusible acrylonitrile polymers can be melt-extruded to form an elongate member at temperatures below the temperature at which they decompose.
  • such polymers may alternatively be extruded by wet- and dry-spinning techniques.
  • Carbon fibres are well-known and are described for example in an article in Encyclopaedia of Polymer Science and Engineering, Volume 2 (Wiley-Interscience, 1985) entitled “Carbon Fibers", at page 640.
  • Carbon fibres are made by controlled pyrolysis of an organic precursor, for example an acrylonitrile polymer, in fibrous form. Pyrolysis of acrylonitrile polymers typically involves a number of pyrolysis steps. The first step, which may be called the stabilisation step or the oxidation, pre-oxidation or thermosetting step, is carried out at relatively low temperatures, typically in the range 200-450°C, usually in air. The oxidised fibre may then be converted to carbon fibre (carbonised) by heating in an inert atmosphere at 1000-2000 °C, or it may be graphitised by heating in an inert atmosphere at temperatures in excess of 2500 °C.
  • melt-extrusion techniques have certain advantages over dry- and wet-extrusion techniques for the manufacture of elongate members, notably in the relative simplicity of the apparatus required. Furthermore, it is known that melt-extrusion often lends itself more readily to the production of extruded members of modified cross-section by extrusion though a die of modified cross -section than do wet- and dry-extrusion techniques. However, it will readily be appreciated that melt-extruded fusible acrylonitrile polymers cannot readily be pyrolysed to form oxidised, carbonised or graphitised articles . Such polymers melt below the temperature at which they can be oxidised.
  • the present invention provides a method for manufacturing an elongate member comprising the steps of
  • the elongate member may take the form of a film or preferably a fibre.
  • Suitable fusible acrylonitrile polymers for use in the invention and methods for their manufacture and melt-extrusion are described for example in US-A-5 , 106 , 925 and US-A-5, 286, 828.
  • the fusible acrylonitrile polymer generally contains at least 50 percent by weight acrylonitrile monomer units.
  • the cross -linking step (2) may be effected in a variety of ways.
  • the extruded elongate member may be exposed to ionising radiation so as to induce cross-linking.
  • the elongate member may be treated with a chemical reagent which serves to induce cross-linking in acrylonitrile polymers, for example ammonia, hydrazine or a primary or secondary amine .
  • the fusible acrylonitrile polymer may comprise monomer units which possess a cross- linkable group other than the nitrile group, for example olefinic or hydroxyl groups.
  • Cross -linking may in such cases be induced in the melt -extruded elongate member by subjecting it to conditions which cause reaction of the cross -linkable group, for example in the case of an olefinic group exposure to UV radiation or in the case of a hydroxyl group etherification or reaction with a bifunctional reagent. Care should be taken to avoid excessive cross -linking before and during the melt-extrusion step, because this may adversely affect the physical properties of the melt-extruded member.
  • the cross -linkable group should accordingly possess sufficient thermal stability to resist excessive cross -linking during melt -extrusion.
  • the acrylonitrile polymer may comprise latent cross- linkable groups.
  • it may comprise t-butyl vinyl ether monomer units serving to provide latent cross-linkable groups, whereby the ether groups can be hydrolysed after melt-extrusion to yield hydroxymethylene groups as cross -linkable groups.
  • the cross-linked infusible polymer is preferably one which does not show any tendency to melt below about 300 * C. This permits the cross-linked polymer to be oxidised and subsequently pyrolysed using techniques generally known for acrylonitrile elongate members, including fibres.
  • the invention further provides a method which further includes the step of (3) pyrolysing the cross- linked elongate member under oxidising conditions, thereby producing an oxidised acrylonitrile elongate member.
  • the invention yet further provides a method which in addition to step (3) further includes the step of (4) pyrolysing said oxidised elongate member under anaerobic conditions, thereby producing a carbonised or a graphitised elongate member.
  • Cross -linked elongate members produced by the method of the invention in the form of fibres are suited to the manufacture of carbon fibres, for example for use in fire-retardant materials and in battery separators.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Textile Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Health & Medical Sciences (AREA)
  • Materials Engineering (AREA)
  • Toxicology (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Fibers (AREA)
  • Artificial Filaments (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)

Abstract

A melt article, e.g. a fibre or film, or a fusible acrylonitrile polymer can be cross-linked to render it infusible. The thusly cross-linked article can be oxidised and subsequently carbonised or graphitised in similar manner to articles made by wet- or dry-extrusion of infusible acrylonitrile polymers.

Description

MANUFACTURE OF ELONGATE MEMBERS
Field of the invention
This invention relates to the manufacture of elongate members based on acrylonitrile polymers and to their oxidation, carbonisation and graphitisation.
Background art
Acrylonitrile polymers are well-known and are described for example in articles in Encyclopaedia of Polymer Science and Engineering, Volume 1 ( iley-Interscience, 1985) entitled "Acrylonitrile Polymers", at page 426, and "Acrylic Fibers", at page 334. Acrylic polymers are defined as polymers which contain at least 85% by weight acrylonitrile monomer units. Modacrylic polymers are defined as polymers which contain 40 to 85% by weight acrylonitrile monomer units. Many acrylonitrile polymers, including a large proportion of acrylic polymers, are infusible and decompose without melting when they are heated. Processes are known by which such polymers can be processed into elongate members, for example fibres, using wet- or dry-extrusion techniques. These involve the extrusion of a solution of the polymer in a suitable solvent into a coagulating bath or an evaporative atmosphere, respectively. Processes are also known whereby elongate members can be manufactured by extrusion of a plasticised acrylonitrile polymer under dry-spinning conditions, followed by removal of the plasticiser. Fusible acrylonitrile polymers are also known and are described for example in US-A-5 , 106 , 925 and US-A-5 , 286 , 828 (both Curatolo et al . ) , the contents of which are incorporated herein by way of reference. Such fusible acrylonitrile polymers can be melt-extruded to form an elongate member at temperatures below the temperature at which they decompose. In general, such polymers may alternatively be extruded by wet- and dry-spinning techniques.
Carbon fibres are well-known and are described for example in an article in Encyclopaedia of Polymer Science and Engineering, Volume 2 (Wiley-Interscience, 1985) entitled "Carbon Fibers", at page 640. Carbon fibres are made by controlled pyrolysis of an organic precursor, for example an acrylonitrile polymer, in fibrous form. Pyrolysis of acrylonitrile polymers typically involves a number of pyrolysis steps. The first step, which may be called the stabilisation step or the oxidation, pre-oxidation or thermosetting step, is carried out at relatively low temperatures, typically in the range 200-450°C, usually in air. The oxidised fibre may then be converted to carbon fibre (carbonised) by heating in an inert atmosphere at 1000-2000 °C, or it may be graphitised by heating in an inert atmosphere at temperatures in excess of 2500 °C.
Melt-extrusion techniques have certain advantages over dry- and wet-extrusion techniques for the manufacture of elongate members, notably in the relative simplicity of the apparatus required. Furthermore, it is known that melt-extrusion often lends itself more readily to the production of extruded members of modified cross-section by extrusion though a die of modified cross -section than do wet- and dry-extrusion techniques. However, it will readily be appreciated that melt-extruded fusible acrylonitrile polymers cannot readily be pyrolysed to form oxidised, carbonised or graphitised articles . Such polymers melt below the temperature at which they can be oxidised.
Disclosure of the invention
The present invention provides a method for manufacturing an elongate member comprising the steps of
(1) melt -extruding a fusible acrylonitrile polymer to produce an elongate member, and as characterising step
(2) cross -linking said polymer in said elongate member, thereby rendering it infusible.
The elongate member may take the form of a film or preferably a fibre.
Suitable fusible acrylonitrile polymers for use in the invention and methods for their manufacture and melt-extrusion are described for example in US-A-5 , 106 , 925 and US-A-5, 286, 828. The fusible acrylonitrile polymer generally contains at least 50 percent by weight acrylonitrile monomer units.
The cross -linking step (2) may be effected in a variety of ways. For example, the extruded elongate member may be exposed to ionising radiation so as to induce cross-linking. Alternatively, the elongate member may be treated with a chemical reagent which serves to induce cross-linking in acrylonitrile polymers, for example ammonia, hydrazine or a primary or secondary amine . Further alternatively, the fusible acrylonitrile polymer may comprise monomer units which possess a cross- linkable group other than the nitrile group, for example olefinic or hydroxyl groups. Cross -linking may in such cases be induced in the melt -extruded elongate member by subjecting it to conditions which cause reaction of the cross -linkable group, for example in the case of an olefinic group exposure to UV radiation or in the case of a hydroxyl group etherification or reaction with a bifunctional reagent. Care should be taken to avoid excessive cross -linking before and during the melt-extrusion step, because this may adversely affect the physical properties of the melt-extruded member. The cross -linkable group should accordingly possess sufficient thermal stability to resist excessive cross -linking during melt -extrusion. Further alternatively, the acrylonitrile polymer may comprise latent cross- linkable groups. For example, it may comprise t-butyl vinyl ether monomer units serving to provide latent cross-linkable groups, whereby the ether groups can be hydrolysed after melt-extrusion to yield hydroxymethylene groups as cross -linkable groups.
The cross-linked infusible polymer is preferably one which does not show any tendency to melt below about 300 *C. This permits the cross-linked polymer to be oxidised and subsequently pyrolysed using techniques generally known for acrylonitrile elongate members, including fibres. The invention further provides a method which further includes the step of (3) pyrolysing the cross- linked elongate member under oxidising conditions, thereby producing an oxidised acrylonitrile elongate member. The invention yet further provides a method which in addition to step (3) further includes the step of (4) pyrolysing said oxidised elongate member under anaerobic conditions, thereby producing a carbonised or a graphitised elongate member.
Cross -linked elongate members produced by the method of the invention in the form of fibres are suited to the manufacture of carbon fibres, for example for use in fire-retardant materials and in battery separators.

Claims

1. A method for manufacturing an elongate member comprising the steps of (1) melt-extruding a fusible acrylonitrile polymer to produce an elongate member, and as characterising step (2) cross-linking said polymer in said elongate member, thereby rendering it infusible.
2. The method according to claim 1, further including the step (3) of pyrolysing said elongate member after cross- linking said polymer, said pyrolysing being carried out under oxidising conditions, thereby producing an oxidised elongate member.
3. The method according to claim 2, further including the step of (4) pyrolysing said oxidised elongate member under anaerobic conditions, thereby producing a carbonised or graphitised elongate member.
4. The method according to any of claims 1 to 3 , characterised in that the elongate member is a fibre.
5. The use of an elongate member produced by a method as claimed in any of claims 1 for the manufacture of carbon fibres.
EP98900898A 1997-01-17 1998-01-15 Manufacture of elongate members Withdrawn EP0953071A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB9700946A GB2321215A (en) 1997-01-17 1997-01-17 Cross-linked acrylonitrile precursors for carbon fibres
GB9700946 1997-01-17
PCT/GB1998/000124 WO1998031852A1 (en) 1997-01-17 1998-01-15 Manufacture of elongate members

Publications (1)

Publication Number Publication Date
EP0953071A1 true EP0953071A1 (en) 1999-11-03

Family

ID=10806159

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98900898A Withdrawn EP0953071A1 (en) 1997-01-17 1998-01-15 Manufacture of elongate members

Country Status (10)

Country Link
EP (1) EP0953071A1 (en)
JP (1) JP2001508842A (en)
KR (1) KR20000069731A (en)
CN (1) CN1091809C (en)
AU (1) AU5670898A (en)
CA (1) CA2278484A1 (en)
EA (1) EA001275B1 (en)
GB (1) GB2321215A (en)
IL (1) IL130670A0 (en)
WO (1) WO1998031852A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU3365400A (en) * 1999-02-22 2000-09-14 Standard Oil Company, The Carbon fibers or sheets made from copolymers of acrylonitrile
US6630555B2 (en) 2001-11-06 2003-10-07 Lord Corporation Internally blocked organoborate initiators and adhesives therefrom
CN101798392B (en) * 2009-12-11 2012-01-04 中国科学院上海应用物理研究所 Method for modifying polyacrylonitrile by using gamma ray irradiation

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1033141A (en) * 1962-04-17 1966-06-15 Courtaulds Ltd Process for modifying synthetic fibres
US3414498A (en) * 1963-04-09 1968-12-03 Toyo Rayon Co Ltd Cross-linking of polymeric substances with acetylene and ionizing radiation
DE1929849C3 (en) * 1969-06-12 1973-10-18 Sigri Elektrographit Gmbh Process for the production of carbon or graphite fibers
GB1283714A (en) * 1969-07-09 1972-08-02 Ici Ltd Process for the production of carbon fibres
BE755579A (en) * 1970-04-07 1971-03-01 Sigri Elektrographit Gmbh CARBON AND GRAPHITE FIBER MANUFACTURING PROCESS
US3917776A (en) * 1970-12-12 1975-11-04 Mitsubishi Rayon Co Process for producing carbon fiber
GB1580529A (en) * 1975-10-24 1980-12-03 Nat Res Dev Polymers useful for producing carbon fibres
US4473372A (en) * 1983-05-12 1984-09-25 Celanese Corporation Process for the stabilization of acrylic fibers
JPS62149918A (en) * 1985-12-25 1987-07-03 Mitsubishi Rayon Co Ltd Production of heat-resistant acrylonitrile yarn
US4921656A (en) * 1988-08-25 1990-05-01 Basf Aktiengesellschaft Formation of melt-spun acrylic fibers which are particularly suited for thermal conversion to high strength carbon fibers
US5436275A (en) * 1993-11-30 1995-07-25 Japan Exlan Company Limited Porous acrylonitrile polymer fiber
US5509986A (en) * 1994-08-22 1996-04-23 The Dow Chemical Company Process for preparing an ignition resistant carbonaceous material comprising a melt blowing or spunbonding step, a radiation step and a carbonizing step

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9831852A1 *

Also Published As

Publication number Publication date
EA001275B1 (en) 2000-12-25
WO1998031852A1 (en) 1998-07-23
CA2278484A1 (en) 1998-07-23
KR20000069731A (en) 2000-11-25
JP2001508842A (en) 2001-07-03
IL130670A0 (en) 2000-06-01
AU5670898A (en) 1998-08-07
GB2321215A (en) 1998-07-22
CN1243554A (en) 2000-02-02
CN1091809C (en) 2002-10-02
GB9700946D0 (en) 1997-03-05
EA199900666A1 (en) 2000-02-28

Similar Documents

Publication Publication Date Title
Huang Fabrication and properties of carbon fibers
Gupta et al. Acrylic precursors for carbon fibers
US4778633A (en) Method of making high strength polyethylene fiber
US3412062A (en) Production of carbon fibres and compositions containing said fibres
US3392216A (en) Method for producing carbon structures from molten baked substances
US4853164A (en) Method of producing high strength fibers
KR850008366A (en) Gel Spun, Irradiated and Stretched Polyethylene Filaments, Tapes and Films and Methods for Manufacturing the Same
US3923950A (en) Production of stabilized acrylic fibers and films
US3556729A (en) Process for oxidizing and carbonizing acrylic fibers
DE2054626A1 (en) Process for the continuous manufacture of resin-impregnated graphite ribbons
US4002426A (en) Production of stabilized non-burning acrylic fibers and films
WO1998031852A1 (en) Manufacture of elongate members
CN112813539B (en) Preparation method of polyacrylonitrile-based carbon fiber
DE60310862T2 (en) Process for producing an optical fiber with coatings of different nature
Chernikova et al. Melt-Spinnable Polyacrylonitrile—An Alternative Carbon Fiber Precursor
US4452601A (en) Process for the thermal stabilization of acrylic fibers and films
MXPA99006591A (en) Manufacture of elongate members
JP7264190B2 (en) Method for manufacturing carbon material
US3959448A (en) Process for the manufacture of carbon fibers
CA1182957A (en) Thermal stabilization of acrylonitrile copolymer fibers
Youn et al. Improving mechanical properties of melt‐spun polyetherimide monofilaments by thermal drawing
CN112011855B (en) Method for producing carbon fiber
US5091271A (en) Shaped silion carbide-eased ceramic article
Redarn Process for the production of carbon fibres
USRE27794E (en) Heat treatment of molten carbonaceous material prior to its conversion to carbon fibers and other shapes

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19990813

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU NL PT SE

AX Request for extension of the european patent

Free format text: LT PAYMENT 19990813;LV PAYMENT 19990813;MK PAYMENT 19990813;RO PAYMENT 19990813;SI PAYMENT 19990813

17Q First examination report despatched

Effective date: 20010601

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: TENCEL LIMITED

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: ACORDIS UK LIMITED

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20030801