EP0419206B1 - Zellenförmige Körnchen aus Polymer und daraus hergestelltes Papier - Google Patents

Zellenförmige Körnchen aus Polymer und daraus hergestelltes Papier Download PDF

Info

Publication number
EP0419206B1
EP0419206B1 EP90310187A EP90310187A EP0419206B1 EP 0419206 B1 EP0419206 B1 EP 0419206B1 EP 90310187 A EP90310187 A EP 90310187A EP 90310187 A EP90310187 A EP 90310187A EP 0419206 B1 EP0419206 B1 EP 0419206B1
Authority
EP
European Patent Office
Prior art keywords
paper
granules
calcium carbonate
weight
vesiculated
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 - Lifetime
Application number
EP90310187A
Other languages
English (en)
French (fr)
Other versions
EP0419206A1 (de
Inventor
Loreen Doris Ferguson
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.)
PPG Architectural Coatings Canada Inc
Original Assignee
ICI Canada Inc
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 ICI Canada Inc filed Critical ICI Canada Inc
Publication of EP0419206A1 publication Critical patent/EP0419206A1/de
Application granted granted Critical
Publication of EP0419206B1 publication Critical patent/EP0419206B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • DTEXTILES; PAPER
    • D21PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21HPULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20Macromolecular organic compounds
    • D21H17/33Synthetic macromolecular compounds
    • D21H17/46Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/53Polyethers; Polyesters
    • DTEXTILES; PAPER
    • D21PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21HPULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/50Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by form
    • D21H21/52Additives of definite length or shape
    • D21H21/54Additives of definite length or shape being spherical, e.g. microcapsules, beads

Definitions

  • This invention relates to vesiculated polymer granules and more particularly, to paper comprising said granules.
  • Paper is typically manufactured by transferring a suspension (or furnish) of fibrous material, sizing materials, wet and dry strength additives, defoamers, biocides, dyes, pigments, retention aids and/or fillers, to a forming wire for water drainage to concentrate solids.
  • the paper formed on the wire is subsequently dried to a desired basis weight (weight per unit area).
  • the fibrous material used in papermaking is cellulosic or non-cellulosic in form, e.g. plant matter, such as trees, cotton, bagasse, and synthetic polymers, such as rayon, which may have been delignified and/or bleached.
  • fillers are normally added during paper production in order to replace a portion of the expensive pulp fibres with less expensive material.
  • the fillers of choice for alkaline paper which in this specification means any paper produced from an aqueous fibrous suspension of pH 7 or greater, are usually selected from the class of mineral fillers known as clays, such as kaolin, and calcium carbonates.
  • the calcium carbonates of use as paper making fillers fall under three classifications, namely, ground, chalk and precipitated carbonates.
  • Ground calcium carbonates occur naturally in the earth and are mined and milled to a desired particle size.
  • the chalk form of calcium carbonate is the skeletal remains of marine organisms, while the precipitated calcium carbonate is a man-made form of calcium carbonate prepared by bubbling carbon dioxide gas through an aqueous slurry of calcium hydroxide, followed by precipitation of the calcium carbonate produced.
  • Calcium carbonate is not used in acidic paper making because calcium carbonate would cause foaming in the acidic aqueous paper composition due to the production of carbon dioxide.
  • Fillers are also generally used to impart suitable optical properties, namely, whiteness, brightness, opacity, and colour, and surface properties, such as, smoothness and printability.
  • the degree of opacity of a particular substrate is the result of diffuse light-scattering which occurs when visible radiation is reflected from particles on the surface of the substrate and the substrate medium itself.
  • inorganic mineral fillers mentioned hereinabove, and in particular calcium carbonate it is customary to use the inorganic mineral fillers mentioned hereinabove, and in particular calcium carbonate, to enhance the optical and surface properties of paper sheets.
  • inorganic mineral filler which can be added to the paper.
  • inorganic mineral filler content increases, there is a substantial loss of the physical strength properties of the paper. This loss of physical properties results because of interference with the hydrogen bonding between the strands of fibrous material, by the filler, and because with increased inorganic mineral filler content there is less fiber present in the paper sheet to contribute to the strength.
  • vesiculated granules of carboxylated unsaturated polyester crosslinked with ethylenically unsaturated monomer can confer advantageous properties, such as improved opacity to paper and coating compositions in which they are incorporated.
  • the background to the use of vesiculated granules in papermaking is well covered in the literature, for example, in articles by Kershaw (Australian OCCA Proceedings and News, August 1971), and Treier (TAPPI, Vol. 55, No. 5, 1972).
  • pigment may be dispersed in either or both of the first emulsion components using conventional pigment dispersants and defoamers.
  • the technique of preparing vesiculated materials is discussed in detail in EP-A-0,307,139 (equivalent to US-A-4,808,633, assigned to CIL Inc.) wherein the use of a specific alkyl acryloyl derivative-containing polymeric vesiculated granule, for making paper is described.
  • the granule is added to provide improved retention of fines and for increased opacity.
  • No reference is made to improved physical properties, or to the use of the high levels of calcium carbonate contemplated in the present invention.
  • EP-A-0,204,916 and EP-A-0,268,729 describe methods for producing high bulk calendered paper containing vesiculated beads.
  • EP-A-0,204,916 describes a high bulk calendered paper wherein the opacity of the paper is increased by the addition of vesiculated granules in the amount of 0.5 to 15%, and preferably 2 to 10%, by weight of the paper produced. Papers produced according to EP-A-0,204,916 have increased thickness and resistance to print show through, while the brightness and opacity of the paper is maintained. This allows the amount of titanium dioxide pigment to be reduced, which lowers the cost of the resulting paper.
  • EP-A-0,268,729 describes a similar paper as in EP-A-0,204,916 with increased thickness and resistance to print show through while maintaining brightness and opacity, wherein the polymeric vesiculated granule concentration is between 2 and 6%, and preferably 4 and 6%, of the total paper weight.
  • a neutralized polycarboxylic acid polymer thickener is added to reduce the proportion of fines which pass through the paper forming wire.
  • EP-A-0,268,729 and EP-A-0,204,916 describe paper compositions prepared from acidic furnishes.
  • the aqueous furnish has a pH of from 4 to 6.
  • Both patent applications also state that physical properties are maintained by the replacement of titanium dioxide with polymeric vesiculated granules.
  • both patents are silent on the use of polymeric vesiculated granules in an alkaline paper composition, and in particular, paper compositions which comprise calcium carbonate filler.
  • the improvement, according to the present invention, that has been observed in the physical properties of alkaline paper, allows the paper maker to lower the cost of the paper produced by either adding additional calcium carbonate and, thus, replacing additional expensive fibrous material while maintaining constant physical properties; or by increasing the line speed of the paper machine, because of the improved physical properties of the paper, and thus producing additional paper per unit time.
  • the present invention provides an alkaline paper as hereinbefore defined, comprising a fibrous cellulosic material; 1.0 to 10.0%, by weight of the paper, of polymeric vesiculated granules; and 5 to 35% by weight of paper, of calcium carbonate filler.
  • the invention provides an alkaline paper as hereinbefore defined wherein said alkaline paper comprises 1 to 5% of said polymeric vesiculated granules.
  • the invention provides an alkaline paper as hereinabove defined wherein said calcium carbonate level is between 10 and 25% by weight of paper.
  • precipitated or ground calcium carbonates are preferred, with precipitated calcium carbonate being the most preferred.
  • fillers in addition to calcium carbonate, other fillers, pigments, extenders and/or opacifiers such as titanium dioxide, clay and talc may be added to the paper suspension in accordance with the papermaking prior art or may be added to the vesiculated granule during production of the granule.
  • opacifiers such as titanium dioxide, clay and talc
  • vesiculated polymer granules By vesiculated polymer granules is meant granules of polymer, preferably spheroidal granules, which have a cell-like structure, the walls of which are provided by the polymer.
  • the granules comprise a plurality of cells or vesicles (that is they are not mono-cellular or balloon-like) and although the vesicles are not necessarily of uniform size, the ratio of the diameter of the granule to the mean individual vesicle diameter is generally at least 5:1.
  • the vesicles typically occupy from 5 to 95% of the total volume of the granules and the maximum diameter of the vesicles is 20 ⁇ m.
  • Low vesicle volumes are usually associated with granules of high mechanical strength which are particularly useful for some applications, but to achieve the most useful opacifying effects the vesicles typically occupy at least 20% of the total volume of the granules, preferably 20-75% of the volume.
  • the invention provides an alkaline paper as described hereinabove wherein said granules have a mean diameter of 1 to 100 ⁇ m, the ratio of the granule to the mean vesicle diameter is at least 5:1, the maximum diameter of the vesicles is 20 ⁇ m, and volume of the vesicles is from 5 to 95% of the volume of the granule.
  • the granules have substantially continous, solid walls and have a preselected and targeted particle size. Broadly, the granules may have a mean diameter of 1 to 100 ⁇ m. In general we find that granules having a mean diameter of 1 to 50 ⁇ m are of the most value as opacifying agents.
  • polyelectrolyte retention aids it is customary to incorporate in the dilute paper furnish, immediately prior to formation on the wire, small amounts of polyelectrolyte retention aids to give improved retention of the inorganic mineral fillers and any fine fractions of the cellulosic materials on the wire during sheet formation.
  • a cationic retention aid is used to prepare or "condition" the furnish prior to the addition of an anionic retention aid.
  • the dual retention aid system is usually comprised of polymeric polyelectrolytes, e.g. polyacrylamides and polyethyleneimines.
  • a further aspect of the present invention is the alkaline aqueous compositions, which in this specification means any a composition of pH 7 or greater used, in the preparation of the papers of the present invention, described hereinabove.
  • the invention further provides an alkaline aqueous composition
  • a fibrous material 1.0 to 10% of polymeric vesiculated granules, and 5 to 35% of calcium carbonate filler wherein the percentages expressed are as percentages by weight of the resultant paper produced from said composition.
  • the aqueous slurry of vesiculated polyester granules that is formed according to the technique described in U.S. Patent No. 4,808,633 may be used directly in paper wet-end applications.
  • the aqueous slurry of vesiculated polyester granules may also be dewatered, by any convenient means, for example by the method described in United States Patent No. 4,154,923 and subsequently redispersed in an aqueous or non-aqueous medium, before being incorporated into the paper furnish.
  • the pulp component of the alkaline paper to be produced can be formed in part or totally from hardwood, softwood and recycled pulps and/or broke if desired, incorporating an internal sizing agent, for example, alkyl ketene dimer emulsion, or alkyl succinic anhydride.
  • an internal sizing agent for example, alkyl ketene dimer emulsion, or alkyl succinic anhydride.
  • the upper limit of usefulness for the vesiculated polymeric granules be 10 weight percent of the total paper solids. Because of the cost of the polymeric vesiculated granules and because of a diminishing improvement in physical properties at higher levels of granules, it is preferred that the level of granules be less than 5 weight percent and even more preferably less than 3 weight percent.
  • Pigmented vesiculated polyester resin granules having a 10 ⁇ m (95 percentile) diameter maximum, 5.2 ⁇ m mean average diameter of use in the practice of the present invention were prepared according to the technique of Example 1 of U.S.-A-4,808,633 but with the following formulation.
  • Table A outlines some of the physical parameters of the granules obtained.
  • TABLE A Property 10 ⁇ m Pigmented Vesiculated Granules Density of dried granules 0.59 g/ml % vesiculation (1) 65% Weight solids 21.2% Volume solids 36% Maximum granule size (2) 12 ⁇ m Median granule size 5.2 ⁇ m Minimum granule size 3 ⁇ m Vesicle pore size (3) 0.5-3.0 ⁇ m Surface pores on granule ⁇ 0.2 ⁇ m Thickness of granule wall 0.1-0.5 ⁇ m Note: (1) vesiculation determined by mercury porisimetry (2) granule size determined by Laser Diffraction Granulometer (3) internal diameters measured using Scanning Electron Microscopy
  • Freeness of pulp is a measure of the drainage rate of water through the pulp and is measured in accordance with the TAPPI (Technical Association of Pulp and Paper Industry) Standard T 227 om-75 and is referred to as Canadian Standard Freeness, measured in millilitres;
  • Opacity of the paper sheet is expressed as a contrast ratio opacity (C/R Opacity) and measured in accordance with TAPPI Standard T 425 om-81 using light with a wavelength of 572 nanometers;
  • the term handsheet is used to refer to a paper sheet made in accordance with and employing the equipment described in the TAPPI standard T 205 om-81; and Conditioning refers to the conditioning atmosphere of 23.0°C +/- 1°C, and 50.0% +/- 2.0% relative humidity that the paper sheets are exposed to in accordance with TAPPI standards T 405 om-83.
  • Handsheets as discussed hereinbelow in Example 2 were prepared by the following general procedure.
  • the solids in the final pulp slurrys were comprised of fully bleached kraft hardwood or softwood pulps that had been soaked in water for four hours and were refined to a Canadian Standard Freeness(CSF) of 400 or 600mls. After refining, the pulps were mixed together and then divided into individual samples of pulp calculated to give a target basis weight when combined with the fillers.
  • the pulp samples were dispersed in water, and cationic polymeric retention aid was added.
  • the pH of the furnish was controlled to 7.8 to 8.2 by the addition of dilute sodium hydroxide as required.
  • the furnish was subsequently passed through a sheetmaker and the resultant handsheet pressed and conditioned.
  • the hereinabove general procedure for the preparation of handsheets was carried out to prepare a number of different samples for testing of physical properties.
  • the furnish comprised a fully bleached kraft hardwood/softwood (50/50) pulp blend and filler or filler blends comprising polymeric vesiculated granules (PVG), precipitated calcium carbonate (PCC), and/or titanium dioxide (TiO2).
  • PVG polymeric vesiculated granules
  • PCC precipitated calcium carbonate
  • TiO2 titanium dioxide
  • the hardwood pulp had a CSF of 400mls and the softwood had a CSF of 600mls.
  • the PCC has an average particle size of 1.2 ⁇ m and has a scalenohedral crystal form.
  • the retention aids were commercially available cationic and anionic polyacrylamides.
  • the physical properties of the various handsheets were tested according to the following TAPPI standard test methods for paper: T220 OM-88 Physical Testing of pulp handsheets T
  • handsheet number 16 which contains no pigment, filler or polymeric vesiculated granules and constitutes the fibrous material only, demonstrates superior physical properties to the other handsheets prepared. However, this handsheet would have the highest cost of all of the handsheets since it comprises pulp fibre only and, has the lowest C/R opacity.
  • handsheets 1 to 15 which handsheets comprise calcium carbonate, titanium dioxide and/or polymeric vesiculated granules, are approximately equal, with opacity generally increasing as total filler level increases.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Paper (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Multicomponent Fibers (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Claims (9)

  1. Alkalipapier, umfassend einen Zellulosefaserstoff; 1,0 bis 10,0 Gew.-% des Papiers an polymeren blasenartigen Körnchen; und 5 bis 35 Gew.-% des Papiers an Kalziumkarbonat-Füllstoff.
  2. Papier nach Anspruch 1, wobei die genannten Körnchen einen mittleren Durchmesser von 1 bis 100 Mikrometer aufweisen, das Verhältnis eines Körnchens zum mittleren Bläschendurchmesser wenigstens 5:1 beträgt, der maximale Bläschendurchmesser 20 Mikrometer beträgt und das Volumen der Bläschen zwischen 5% und 95% des Körnchenvolumens liegt.
  3. Papier nach Anspruch 2, wobei die genannten Körnchen einen mittleren Durchmesser von 1 bis 50 Mikrometer haben.
  4. Papier nach Anspruch 1, umfassend 1,0 bis 5,0 Gew.-% der genannten Körnchen.
  5. Papier nach Anspruch 1, umfassend 10 bis 25 Gew.-% an Kalziumkarbonat.
  6. Papier nach einem der Ansprüche 1, 2 oder 3, wobei das genannte Kalziumkarbonat präzipitiert ist.
  7. Papier nach einem der Ansprüche 1, 2 oder 3, das weiterhin ein Haltemittel umfaßt.
  8. Papier nach einem der Ansprüche 1, 2 oder 3, das weiterhin andere herkömmliche Papierfüllstoffe oder - pigmente umfaßt.
  9. Verfahren zur Verbesserung der physikalischen Eigenschaften von Alkalipapier, umfassend die folgenden Schritte:
    (i) Zubereiten einer wäßrigen Mischung aus einem Zellulosefaserstoff, 5 bis 35 Gew.-% der Zellulosestoff-Festkörper an Kalziumkarbonat-Füllstoff und 1 bis 10 Gew.-% der Zellulosestoff-Festkörper an polymeren blasenartigen Körnchen; und
    (ii) Entfernen des Wassers aus der genannten Mischung zum Herstellen von Alkalipapier.
EP90310187A 1989-09-21 1990-09-18 Zellenförmige Körnchen aus Polymer und daraus hergestelltes Papier Expired - Lifetime EP0419206B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US41046689A 1989-09-21 1989-09-21
US410466 1989-09-21
CA000614385A CA1335688C (en) 1989-09-21 1989-09-28 Vesiculated polymer granules and paper made therefrom

Publications (2)

Publication Number Publication Date
EP0419206A1 EP0419206A1 (de) 1991-03-27
EP0419206B1 true EP0419206B1 (de) 1994-08-31

Family

ID=25673140

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90310187A Expired - Lifetime EP0419206B1 (de) 1989-09-21 1990-09-18 Zellenförmige Körnchen aus Polymer und daraus hergestelltes Papier

Country Status (6)

Country Link
EP (1) EP0419206B1 (de)
JP (1) JPH03130497A (de)
AT (1) ATE110811T1 (de)
AU (1) AU635330B2 (de)
CA (1) CA1335688C (de)
DE (1) DE69012028T2 (de)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1602783B1 (de) * 2004-04-23 2014-02-26 Rohm And Haas Company Verfahren zur Herstellung von Papier
DE602005024078D1 (de) * 2004-04-23 2010-11-25 Rohm & Haas Verfahren zur Herstellung eines Dekorlaminats
US20050236125A1 (en) * 2004-04-23 2005-10-27 Brown James T Method of preparing paper

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3779055D1 (de) * 1986-11-10 1992-06-17 Rohm & Haas Herstellung von blaeschengefuellte perlen enthaltendes, hochbauschiges kalandriertes papier.
GB2201171B (en) * 1987-02-14 1991-01-02 Laporte Industries Ltd Compositions for use in the treatment of cellulosic materials and their preparation
US4808633A (en) * 1987-09-08 1989-02-28 C-I-L Inc. Vesiculated polymer granules

Also Published As

Publication number Publication date
AU635330B2 (en) 1993-03-18
EP0419206A1 (de) 1991-03-27
AU6309090A (en) 1991-03-28
DE69012028T2 (de) 1994-12-22
ATE110811T1 (de) 1994-09-15
DE69012028D1 (de) 1994-10-06
JPH03130497A (ja) 1991-06-04
CA1335688C (en) 1995-05-30

Similar Documents

Publication Publication Date Title
EP0403849B1 (de) Expandierte Fasern und Mineralpigment enthaltendes Papier mit hoher Opazität
US6599391B2 (en) Filler for use in paper manufacture and procedure for producing a filler
CA2254268C (en) Filler for use in paper manufacture and method for producing it
EP0261820B1 (de) Füllstoffzusammensetzungen und ihre Verwendung bei der Herstellung von faserigen Blattmaterialien
EP0738303B1 (de) Behandlung von anorganischem papierfüllmaterial mit polysacchariden
US4313790A (en) Additives for increased retention and pitch control in paper manufacture
US20080073049A1 (en) Fibrous web and process for the preparation thereof
EP1392923B1 (de) Mehrschichtiges faserprodukt und verfahren zu seiner herstellung
EP1392920B1 (de) Beschichtetes faservlies und verfahren zu seiner herstellung
EP1084297B1 (de) Verwendung von kolloidalem ausgefälltem kalziumkarbonat als füllstoff bei der herstellung von papier
AU2002247793A1 (en) Coated fibrous web and process for the production thereof
EP0935020B1 (de) Verfahren zur Herstellung von Papierstoff, der so hergestellte Papierstoff und seine Verwendung in Papier und Pappe
US6264907B1 (en) Process for producing silica particles suitable for use as filler for paper
SK58896A3 (en) Inorganic pigment treated with carboxymethylcellulose derivatives, process for the production of said pigment and its use for the production of paper
NO177542B (no) Fremgangsmåte for fremstilling av en fylt fibermasse, samt fylt papir med höy strekkstyrke
EP0419206B1 (de) Zellenförmige Körnchen aus Polymer und daraus hergestelltes Papier
US5332473A (en) Vesiculated polymer granules and paper made therefrom
NZ235366A (en) Alkaline paper and composition, with improved physical properties
Klungness et al. Lightweight, High Opacity Paper: Process Costs and Energy Use Reduction
Perng et al. Effects of adding co-ground talc and calcium carbonate on the retention and paper properties of handsheets
Perng YuanShing et al. Effects of adding co-ground talc and calcium carbonate on the retention and paper properties of handsheets.

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

AK Designated contracting states

Kind code of ref document: A1

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

17P Request for examination filed

Effective date: 19910411

17Q First examination report despatched

Effective date: 19921221

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

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

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRE;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.SCRIBED TIME-LIMIT

Effective date: 19940831

Ref country code: CH

Effective date: 19940831

Ref country code: DK

Effective date: 19940831

Ref country code: AT

Effective date: 19940831

Ref country code: BE

Effective date: 19940831

Ref country code: NL

Effective date: 19940831

Ref country code: LI

Effective date: 19940831

REF Corresponds to:

Ref document number: 110811

Country of ref document: AT

Date of ref document: 19940915

Kind code of ref document: T

ET Fr: translation filed
REF Corresponds to:

Ref document number: 69012028

Country of ref document: DE

Date of ref document: 19941006

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

EAL Se: european patent in force in sweden

Ref document number: 90310187.1

NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

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

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19950911

Year of fee payment: 6

Ref country code: GB

Payment date: 19950911

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19950918

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19950928

Year of fee payment: 6

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19960918

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19960919

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19960930

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19960918

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19970603

EUG Se: european patent has lapsed

Ref document number: 90310187.1

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST