CA2170733A1 - Azurage a concentration moyenne, a l'ozone, de la pate blanchie a haute concentration, a l'ozone - Google Patents
Azurage a concentration moyenne, a l'ozone, de la pate blanchie a haute concentration, a l'ozoneInfo
- Publication number
- CA2170733A1 CA2170733A1 CA002170733A CA2170733A CA2170733A1 CA 2170733 A1 CA2170733 A1 CA 2170733A1 CA 002170733 A CA002170733 A CA 002170733A CA 2170733 A CA2170733 A CA 2170733A CA 2170733 A1 CA2170733 A1 CA 2170733A1
- Authority
- CA
- Canada
- Prior art keywords
- pulp
- ozone
- brightness
- peroxide
- consistency
- 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.)
- Abandoned
Links
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 title claims abstract description 197
- 238000005282 brightening Methods 0.000 title claims abstract description 57
- 238000000034 method Methods 0.000 claims abstract description 106
- 230000008569 process Effects 0.000 claims abstract description 86
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 66
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 64
- 239000001301 oxygen Substances 0.000 claims abstract description 64
- -1 peroxide compound Chemical class 0.000 claims abstract description 31
- 239000012978 lignocellulosic material Substances 0.000 claims abstract description 8
- 150000002978 peroxides Chemical class 0.000 claims description 99
- 230000001965 increasing effect Effects 0.000 claims description 94
- 238000011282 treatment Methods 0.000 claims description 84
- 239000000463 material Substances 0.000 claims description 59
- 239000002245 particle Substances 0.000 claims description 42
- 238000006243 chemical reaction Methods 0.000 claims description 38
- 229920005610 lignin Polymers 0.000 claims description 33
- 238000000605 extraction Methods 0.000 claims description 24
- 238000002156 mixing Methods 0.000 claims description 19
- 239000003381 stabilizer Substances 0.000 claims description 18
- 239000000654 additive Substances 0.000 claims description 14
- 239000008246 gaseous mixture Substances 0.000 claims description 14
- 230000002829 reductive effect Effects 0.000 claims description 9
- 239000012279 sodium borohydride Substances 0.000 claims description 9
- 229910000033 sodium borohydride Inorganic materials 0.000 claims description 9
- 230000000996 additive effect Effects 0.000 claims description 8
- JVBXVOWTABLYPX-UHFFFAOYSA-L sodium dithionite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])=O JVBXVOWTABLYPX-UHFFFAOYSA-L 0.000 claims description 7
- NYYSPVRERVXMLJ-UHFFFAOYSA-N 4,4-difluorocyclohexan-1-one Chemical compound FC1(F)CCC(=O)CC1 NYYSPVRERVXMLJ-UHFFFAOYSA-N 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 238000004061 bleaching Methods 0.000 abstract description 54
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 abstract description 9
- 239000000460 chlorine Substances 0.000 abstract description 9
- 229910052801 chlorine Inorganic materials 0.000 abstract description 9
- 150000001875 compounds Chemical class 0.000 abstract description 5
- 239000012467 final product Substances 0.000 abstract description 5
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 36
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 36
- 239000007789 gas Substances 0.000 description 32
- 239000000126 substance Substances 0.000 description 29
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 28
- 239000011122 softwood Substances 0.000 description 28
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 description 24
- 238000005406 washing Methods 0.000 description 24
- 239000002655 kraft paper Substances 0.000 description 21
- 238000004537 pulping Methods 0.000 description 20
- 239000007844 bleaching agent Substances 0.000 description 17
- 239000011121 hardwood Substances 0.000 description 17
- 239000000203 mixture Substances 0.000 description 16
- 239000000835 fiber Substances 0.000 description 13
- 239000007788 liquid Substances 0.000 description 12
- 229910052943 magnesium sulfate Inorganic materials 0.000 description 12
- 235000019341 magnesium sulphate Nutrition 0.000 description 12
- KFSLWBXXFJQRDL-UHFFFAOYSA-N Peracetic acid Chemical compound CC(=O)OO KFSLWBXXFJQRDL-UHFFFAOYSA-N 0.000 description 11
- 230000007423 decrease Effects 0.000 description 11
- QPCDCPDFJACHGM-UHFFFAOYSA-N N,N-bis{2-[bis(carboxymethyl)amino]ethyl}glycine Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(=O)O)CCN(CC(O)=O)CC(O)=O QPCDCPDFJACHGM-UHFFFAOYSA-N 0.000 description 10
- 239000000243 solution Substances 0.000 description 10
- 229920002678 cellulose Polymers 0.000 description 9
- 239000001913 cellulose Substances 0.000 description 9
- 230000009467 reduction Effects 0.000 description 9
- 235000005018 Pinus echinata Nutrition 0.000 description 8
- 241001236219 Pinus echinata Species 0.000 description 8
- 235000017339 Pinus palustris Nutrition 0.000 description 8
- 230000008901 benefit Effects 0.000 description 8
- 239000002023 wood Substances 0.000 description 8
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 7
- 241000196324 Embryophyta Species 0.000 description 7
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 7
- 235000011613 Pinus brutia Nutrition 0.000 description 7
- 241000018646 Pinus brutia Species 0.000 description 7
- 238000011084 recovery Methods 0.000 description 7
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 6
- 239000013522 chelant Substances 0.000 description 6
- 239000002738 chelating agent Substances 0.000 description 6
- 239000003795 chemical substances by application Substances 0.000 description 6
- 238000010411 cooking Methods 0.000 description 6
- 238000002474 experimental method Methods 0.000 description 6
- 229910021645 metal ion Inorganic materials 0.000 description 6
- 238000006385 ozonation reaction Methods 0.000 description 6
- 239000000123 paper Substances 0.000 description 6
- 239000004115 Sodium Silicate Substances 0.000 description 5
- 230000015556 catabolic process Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 230000007935 neutral effect Effects 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 230000004044 response Effects 0.000 description 5
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 5
- 229910052911 sodium silicate Inorganic materials 0.000 description 5
- 239000002253 acid Substances 0.000 description 4
- 238000000354 decomposition reaction Methods 0.000 description 4
- 238000006731 degradation reaction Methods 0.000 description 4
- OSVXSBDYLRYLIG-UHFFFAOYSA-N dioxidochlorine(.) Chemical compound O=Cl=O OSVXSBDYLRYLIG-UHFFFAOYSA-N 0.000 description 4
- 239000013505 freshwater Substances 0.000 description 4
- 230000008719 thickening Effects 0.000 description 4
- 229920001131 Pulp (paper) Polymers 0.000 description 3
- 238000010306 acid treatment Methods 0.000 description 3
- 230000002378 acidificating effect Effects 0.000 description 3
- 230000002411 adverse Effects 0.000 description 3
- 239000003513 alkali Substances 0.000 description 3
- 239000012670 alkaline solution Substances 0.000 description 3
- PYKYMHQGRFAEBM-UHFFFAOYSA-N anthraquinone Natural products CCC(=O)c1c(O)c2C(=O)C3C(C=CC=C3O)C(=O)c2cc1CC(=O)OC PYKYMHQGRFAEBM-UHFFFAOYSA-N 0.000 description 3
- 150000004056 anthraquinones Chemical class 0.000 description 3
- 239000012159 carrier gas Substances 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 150000004965 peroxy acids Chemical class 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Natural products CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 2
- 239000004155 Chlorine dioxide Substances 0.000 description 2
- 244000166124 Eucalyptus globulus Species 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 230000003190 augmentative effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 150000001805 chlorine compounds Chemical class 0.000 description 2
- 235000019398 chlorine dioxide Nutrition 0.000 description 2
- 230000001143 conditioned effect Effects 0.000 description 2
- 230000003750 conditioning effect Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000000706 filtrate Substances 0.000 description 2
- 238000009897 hydrogen peroxide bleaching Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 235000006408 oxalic acid Nutrition 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 150000004968 peroxymonosulfuric acids Chemical class 0.000 description 2
- 238000004076 pulp bleaching Methods 0.000 description 2
- 238000010791 quenching Methods 0.000 description 2
- 238000012216 screening Methods 0.000 description 2
- 229910052979 sodium sulfide Inorganic materials 0.000 description 2
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 2
- 241000894007 species Species 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- 229910004878 Na2S2O4 Inorganic materials 0.000 description 1
- LYXFCGCYJQCSRL-UHFFFAOYSA-N OOSO Chemical compound OOSO LYXFCGCYJQCSRL-UHFFFAOYSA-N 0.000 description 1
- 101100311043 Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720) sseC gene Proteins 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 125000000837 carbohydrate group Chemical group 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 230000009920 chelation Effects 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 150000007522 mineralic acids Chemical class 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 150000002926 oxygen Chemical class 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000009895 reductive bleaching Methods 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005063 solubilization Methods 0.000 description 1
- 230000007928 solubilization Effects 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/147—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications
- D21C9/153—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications with ozone
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1057—Multistage, with compounds cited in more than one sub-group D21C9/10, D21C9/12, D21C9/16
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/147—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/16—Bleaching ; Apparatus therefor with per compounds
- D21C9/163—Bleaching ; Apparatus therefor with per compounds with peroxides
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
Abstract
L'invention concerne un procédé pour délignifier et décolorer un matériau lignocellulosique (2) sans utiliser de chlore élémentaire ou de composé contenant de chlore. Ce procédé consiste à préparer (4) une pâte à papier, à délignifier (40) la pâte à l'oxygène et ensuite à pousser la délignification de la pâte délignifiée à l'oxygène en soulevant, en déplaçant et en projetant la pâte dans une direction radiale, tout en la faisant avancer dans la direction axiale, à la manière d'un piston, et en la traitant avec une quantité d'ozone suffisante (88) et pendant une durée suffisante pour obtenir une pâte fortement délignifiée, avec un degré de blancheur GE d'au moins 35 % environ. On peut encore blanchir la pâte fortement délignifiée pour obtenir un produit final, en soumettant la pâte à une étape de blanchiment par un composé peroxydé, suivie par un traitement ultérieur à l'ozone de la pâte d'un niveau de concentration de faible à moyen.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US11677693A | 1993-09-03 | 1993-09-03 | |
| US116,776 | 1993-09-03 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2170733A1 true CA2170733A1 (fr) | 1995-03-09 |
Family
ID=22369146
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002170733A Abandoned CA2170733A1 (fr) | 1993-09-03 | 1994-09-01 | Azurage a concentration moyenne, a l'ozone, de la pate blanchie a haute concentration, a l'ozone |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0717800A4 (fr) |
| AU (1) | AU7721694A (fr) |
| BR (1) | BR9407457A (fr) |
| CA (1) | CA2170733A1 (fr) |
| FI (1) | FI960973A (fr) |
| SE (1) | SE9600773L (fr) |
| WO (1) | WO1995006773A1 (fr) |
| ZA (1) | ZA946807B (fr) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2382592A (en) * | 2001-11-30 | 2003-06-04 | Sca Hygiene Prod Gmbh | Use of ozone to enhance the wet strength of fibrous cellulosic material |
| GB2391011A (en) * | 2002-07-19 | 2004-01-28 | Crosmill Ltd | Bleaching cellulose suspensions |
| US9932709B2 (en) | 2013-03-15 | 2018-04-03 | Ecolab Usa Inc. | Processes and compositions for brightness improvement in paper production |
| FR3007044B1 (fr) * | 2013-06-13 | 2016-01-15 | Air Liquide | Procede de traitement des pates papetieres chimiques par traitement a l'ozone en presence d'ions magnesium |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5173153A (en) * | 1991-01-03 | 1992-12-22 | Union Camp Patent Holding, Inc. | Process for enhanced oxygen delignification using high consistency and a split alkali addition |
| EP0402335B2 (fr) * | 1989-06-06 | 2001-03-14 | Eka Chemicals AB | Procédé de blanchiment de pâtes contenant de la lignocellulose |
| AU636173B2 (en) * | 1989-10-30 | 1993-04-22 | Lenzing Aktiengesellschaft | Method for the chlorine-free bleaching of pulps |
| JP2825346B2 (ja) * | 1990-05-17 | 1998-11-18 | ユニオン キャンプ コーポレイション | リグノセルロース物質の環境上改良された漂白方法 |
| US5328564A (en) * | 1990-09-17 | 1994-07-12 | Kamyr, Inc. | Modified digestion of paper pulp followed by ozone bleaching |
| CA2089516A1 (fr) * | 1992-02-21 | 1993-08-22 | Kaj Henricson | Procede de mise en pate et de blanchiment sans chlore |
-
1994
- 1994-09-01 BR BR9407457A patent/BR9407457A/pt not_active Application Discontinuation
- 1994-09-01 WO PCT/US1994/010050 patent/WO1995006773A1/fr not_active Application Discontinuation
- 1994-09-01 EP EP94928024A patent/EP0717800A4/fr not_active Withdrawn
- 1994-09-01 CA CA002170733A patent/CA2170733A1/fr not_active Abandoned
- 1994-09-01 AU AU77216/94A patent/AU7721694A/en not_active Abandoned
- 1994-09-05 ZA ZA946807A patent/ZA946807B/xx unknown
-
1996
- 1996-02-28 SE SE9600773A patent/SE9600773L/xx not_active Application Discontinuation
- 1996-03-01 FI FI960973A patent/FI960973A/fi unknown
Also Published As
| Publication number | Publication date |
|---|---|
| FI960973A (fi) | 1996-04-30 |
| ZA946807B (en) | 1995-06-28 |
| EP0717800A4 (fr) | 1998-10-28 |
| EP0717800A1 (fr) | 1996-06-26 |
| FI960973A0 (fi) | 1996-03-01 |
| BR9407457A (pt) | 1996-11-12 |
| SE9600773D0 (sv) | 1996-02-28 |
| SE9600773L (sv) | 1996-04-18 |
| WO1995006773A1 (fr) | 1995-03-09 |
| AU7721694A (en) | 1995-03-22 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 20000901 |