WO1996016936A1 - Verfahren zur herstellung von caprolactam - Google Patents
Verfahren zur herstellung von caprolactam Download PDFInfo
- Publication number
- WO1996016936A1 WO1996016936A1 PCT/EP1995/004464 EP9504464W WO9616936A1 WO 1996016936 A1 WO1996016936 A1 WO 1996016936A1 EP 9504464 W EP9504464 W EP 9504464W WO 9616936 A1 WO9616936 A1 WO 9616936A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- caprolactam
- reactor
- mixture
- water
- stage
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D201/00—Preparation, separation, purification or stabilisation of unsubstituted lactams
- C07D201/02—Preparation of lactams
- C07D201/08—Preparation of lactams from carboxylic acids or derivatives thereof, e.g. hydroxy carboxylic acids, lactones or nitriles
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Definitions
- the present invention relates to a process for the production of caprolactam by reacting 6-aminocapronitrile with water at elevated temperature.
- the technical problem was therefore to provide a process for the production of caprolactam based on 6-aminocapronitrile which runs with high selectivity in the liquid phase and without a catalyst, in particular the proportion of by-products should be minimized.
- the 6-aminocapronitrile used as the starting material according to the invention is usually obtained by hydrogenating adiponitrile by a known process, for example described in DE-A 836 938, DE-A 848 654 or US Pat. No. 5,151,543.
- reactor A which may contain essentially 6-aminocapronitrile and hexamethylenediamine, adiponitrile and / or caprolactam, as well as high-boiling fractions ("high boilers") which are obtained in the processing of the caprolactam prepared according to the invention.
- an excess of water is preferably used, particularly preferably 10 to 150, in particular 20 to 100, mol of water are used per mole of 6-aminocapronitrile to obtain an aqueous solution of 6-aminocapronitrile.
- 5 to is usually used
- 6-aminocapronitrile 25 moles of water per mole of 6-aminocapronitrile and can generally further dilute the solution to 5 to 25% by weight of 6-aminocapronitrile by adding an organic solvent.
- Ci-C alkanols such as methanol, ethanol, n-, i-propanol, butanols, glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, ethers such as methyl tert-butyl ether, diethylene glycol diethyl ether, C ⁇ -cio-alkanes such as n- Hexane, n-heptane, n-octane, 5 n-nonane, n-decane and cyclohexane, benzene, toluene, xylene, lactams such as pyrrolidone, caprolactam or N-C ⁇ -C 4 alkyl lactams such as N-methylpyrrolidone, N-methylcaprolactam or N-ethylcaprolactam.
- Ci-C alkanols such as methanol, ethanol, n-,
- reaction mixture 10 from 0 to 5, preferably from 0.1 to 2% by weight of ammonia, hydrogen or nitrogen can be added to the reaction mixture 10.
- the reaction in stage (a) is carried out at a temperature in the range from 200 to 370, preferably from 220 to 15, 350 ° C., particularly preferably from 240 to 320 ° C.
- the reaction in stage (a) is usually carried out under pressure, the pressure generally being selected in the range from 0.1 to 50, preferably from 5 to 25, MPa such that the reaction mixture 20 is preferably in the liquid phase.
- the reaction time in reactor A essentially depends on the process parameters selected and, in the process carried out continuously, is generally in the range from 20 to 25 180, preferably from 20 to 90 min. With shorter reaction times, the conversion generally drops, with longer reaction times, disturbing oligomers are formed, as has been observed to date.
- stage (a) is preferably carried out continuously in a reactor A, preferably in a tubular reactor, in stirred tanks or combinations thereof.
- stage (a) can also be carried out batchwise.
- the reaction time is then usually in the range from 30 to 180 min.
- the discharge from reactor A is, according to the invention, a mixture I consisting essentially of 50 to 98, preferably 80 to 95% by weight of water and 2 to 50, preferably 5 to 40, 20% by weight of a mixture consisting of essentially from 50 to 90, preferably from 65 to 85% by weight of caprolactam and from 10 to 50, preferably from 15 to 35% by weight of a high-boiling fraction (hereinafter referred to as "high-boilers").
- high-boilers a high-boiling fraction
- step (b) the water contained in mixture I is removed by customary methods, preferably by distillation, to give a mixture II consisting essentially of from caprolactam and the high boilers.
- distillation is carried out under reduced pressure in the range from 10 to 500 mbar, preferably 50 to 350 mbar, the vacuum distillation column used having from 2 to 20, preferably 5, from 4 to 10 theoretical plates.
- stage (c) the mixture II obtained in stage (b) is separated into a caprolactam-containing fraction (top product) and a fraction containing the high boilers (bottom product)
- step (c) is preferably carried out at a pressure in the range from 0.1 to 100 mbar, preferably from 1 to 20 mbar. Based on the amount of 6-aminocapronitrile used, the yield of caprolactam after this distillation has been observed to be in the range of
- the high boilers obtained in stage (c) can be worked up in three different ways, either
- stage (dl) feeds the high boilers from stage (c) into the reactor A of stage (a), or
- stage (d2) the high boilers are heated in a further reactor B analogously to stage (a) and then analogously to the
- Caprolactam the high boilers preferably being mixed with 5 to 25, preferably 10 to 15 times the amount by weight of water and then at a temperature in the range from 250 to 350, preferably from 280 to 320 ° C. 0 actuator B with a residence time in the range from 30 to 120, preferably from 45 to 90 minutes, or
- stage (d3) the high boilers under reduced pressure in the general range from 1 to 50, preferably from 1 to 10 5 mbar, in the presence of a base, generally from 1 to 10, preferably from 1 to 3,% by weight. %, in a reactor C, preferably in a tubular reactor, heated at a temperature in the range from 200 to 400, preferably from 280 to 320 ° C., and the reaction product is obtained with further capro-lactam, preferably by distillation, preferably at a pressure in the range from 1 to 50, preferably from 1 to 10 mbar.
- a distillation column with a theoretical plate number in the range from 2 to 20, particularly preferably from 5 to 10, is used Alkali metal hydroxides such as sodium hydroxide and potassium hydroxide or a mixture thereof are preferably used as the base.
- the advantage of the process according to the invention is that caprolactam is obtained with high selectivity and high yield from 6-aminocapronitrile in the liquid phase without a catalyst with short reaction times.
- a solution of 10% by weight of 6-aminocapronitrile (ACN) in water was heated to 300 ° C. in a tubular reactor (volume 300 ml), the average residence time being 1 hour. No ACN was detected in the discharge.
- the product mixture (mixture I) contained 90% by weight of water and 10% by weight of a mixture comprising 76% by weight of caprolactam and 24% by weight of high boiler.
- Mixture I was then distilled at a pressure in the range from 100 to 300 mbar in a vacuum distillation column with 5 theoretical plates, with ammonia-containing water as the top product and caprolactam and the high boilers in the column bottom (mixture II).
- Mixture II was separated into a caprolactam fraction (top product) and a high boiler fraction (bottom product) in a further vacuum distillation column (pressure in the range from 3 to 10 mbar).
- the caprolactam yield obtained in this way was 74% by weight, since a further 2% by weight of the amount of caprolactam obtained above was converted to high boilers (essentially oligomeric lactams) during the working up.
- the high boiler fraction from Example 1 was mixed with 10 times the amount by weight of water and heated in a separate reactor at 300 ° C. for 1 hour.
- the resulting product mixture was worked up in the same manner as described in Example 1, 74% by weight of caprolactam being obtained so that the total yield of caprolactam, based on the amount of ACN used, was 93% by weight.
- Example 1 was repeated and then the high boilers were returned to the cyclization reactor (reactor A). The mixture was then worked up as indicated in Example 1, the total yield of caprolactam being 93% by weight.
- Example 4
- Example 1 was repeated.
- the high boilers obtained were mixed with 1% by weight of solid sodium hydroxide and heated to 300 ° C. under reduced pressure at 5 mbar (reactor C).
- the caprolactam formed was continuously removed from equilibrium via a distillation column with 5 theoretical plates.
- the yield of caprolactam was 74%, based on the high boilers, so that the total yield of caprolactam, based on the 6-aminocapronitrile used, was 93%.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Other In-Based Heterocyclic Compounds (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Polyamides (AREA)
- Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
- Mounting Of Bearings Or Others (AREA)
Abstract
Description
Claims
Priority Applications (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PL95320367A PL320367A1 (en) | 1994-11-25 | 1995-11-14 | Caprolactam producing method |
CZ19971469A CZ291034B6 (cs) | 1994-11-25 | 1995-11-14 | Způsob výroby kaprolaktamu |
AT95937070T ATE220061T1 (de) | 1994-11-25 | 1995-11-14 | Verfahren zur herstellung von caprolactam |
EP95937070A EP0793650B1 (de) | 1994-11-25 | 1995-11-14 | Verfahren zur herstellung von caprolactam |
AU39287/95A AU3928795A (en) | 1994-11-25 | 1995-11-14 | Method of producing caprolactam |
DE59510263T DE59510263D1 (de) | 1994-11-25 | 1995-11-14 | Verfahren zur herstellung von caprolactam |
JP8518123A JPH10509963A (ja) | 1994-11-25 | 1995-11-14 | カプロラクタムの製造方法 |
MX9703727A MX9703727A (es) | 1994-11-25 | 1995-11-14 | Preparacion de caprolactama. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE4441962A DE4441962A1 (de) | 1994-11-25 | 1994-11-25 | Verfahren zur Herstellung von Caprolactam |
DEP4441962.7 | 1994-11-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996016936A1 true WO1996016936A1 (de) | 1996-06-06 |
Family
ID=6534115
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP1995/004464 WO1996016936A1 (de) | 1994-11-25 | 1995-11-14 | Verfahren zur herstellung von caprolactam |
Country Status (15)
Country | Link |
---|---|
US (1) | US5495016A (de) |
EP (1) | EP0793650B1 (de) |
JP (1) | JPH10509963A (de) |
KR (1) | KR100403093B1 (de) |
CN (1) | CN1070182C (de) |
AT (1) | ATE220061T1 (de) |
AU (1) | AU3928795A (de) |
CZ (1) | CZ291034B6 (de) |
DE (2) | DE4441962A1 (de) |
ES (1) | ES2179888T3 (de) |
MX (1) | MX9703727A (de) |
MY (1) | MY112192A (de) |
PL (1) | PL320367A1 (de) |
RU (1) | RU2153492C2 (de) |
WO (1) | WO1996016936A1 (de) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999047500A1 (de) * | 1998-03-18 | 1999-09-23 | Basf Aktiengesellschaft | Verfahren zur herstellung von lactamen mit hilfe von oligophosphat-katalysatoren |
Families Citing this family (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4443125A1 (de) * | 1994-12-03 | 1996-06-05 | Basf Ag | Verfahren zur Herstellung von Caprolactam |
DE19500041A1 (de) * | 1995-01-03 | 1996-07-04 | Basf Ag | Verfahren zur kontinuierlichen Reinigung von aus 6-Aminocapronitril hergestelltem Roh-Caprolactam |
DE19517823A1 (de) * | 1995-05-18 | 1996-11-21 | Basf Ag | Verfahren zur Herstellung von Caprolactam |
TW420662B (en) † | 1996-02-17 | 2001-02-01 | Du Pont | Recovery of <epsilon>-caprolactam |
DE19628805A1 (de) * | 1996-07-17 | 1998-01-22 | Basf Ag | Verfahren zur Herstellung von Caprolactam aus 6-Aminocapronitril |
AU3870097A (en) | 1996-10-21 | 1998-05-15 | Dsm N.V. | Process to separate epsilon-caprolactam from 6-aminocaproamide and 6-aminocaproamide oligomers |
EP0860431A1 (de) | 1997-02-19 | 1998-08-26 | Dsm N.V. | Verfahren zur Herstellung von Caprolactam in Abwesenheit von Katalysatoren durch Umsetzung von 6-Aminocapronsäure (oder des Amids) mit überhitztem Wasserdampf |
DE19718706A1 (de) * | 1997-05-02 | 1998-11-05 | Basf Ag | Verfahren zur Herstellung cyclischer Lactame |
DE19738463C2 (de) | 1997-09-03 | 1999-09-23 | Basf Ag | Verfahren zur Herstellung von Caprolactam |
FR2781796B1 (fr) * | 1998-07-28 | 2000-09-22 | Rhone Poulenc Fibres | Procede de deshydratation de lactame |
JP3667140B2 (ja) * | 1999-03-04 | 2005-07-06 | パイオニア株式会社 | ディスクチェンジャ装置 |
US6627046B1 (en) | 2000-01-21 | 2003-09-30 | E. I. Du Pont De Nemours And Company | Separation of the products of polyamide ammonolysis |
US6686465B2 (en) | 2000-05-03 | 2004-02-03 | Basf Aktiengesellschaft | Preparation of cyclic lactams |
DE10021193A1 (de) * | 2000-05-03 | 2001-11-08 | Basf Ag | Verfahren zur Herstellung cyclischer Lactame |
JP4182273B2 (ja) | 2000-06-27 | 2008-11-19 | 住友化学株式会社 | ε−カプロラクタムの製造方法 |
EP1405846A1 (de) * | 2002-10-01 | 2004-04-07 | DSM IP Assets B.V. | Verfahren zur Herstellung von Epsilon-Caprolactam von einer Mischung enthaltend 6-Aminocaproamid und/oder Oligomere |
DE10253094A1 (de) | 2002-11-13 | 2004-05-27 | Basf Ag | Verfahren zur Reinigung von Caprolactam |
DE10253095A1 (de) * | 2002-11-13 | 2004-06-17 | Basf Ag | Verfahren zur Reinigung von Caprolactam |
US6858728B2 (en) * | 2003-06-17 | 2005-02-22 | Invista North America S.A.R.L. | Method for making caprolactam from impure ACN in which THA is not removed until after caprolactam is produced |
DE102008060340A1 (de) | 2008-12-03 | 2010-06-10 | Wolfgang F. Prof. Dr. Hölderich | Herstellung von Lactamen und Carbonsäureamide durch Beckmann-Umlagerung von Oximen in Gegenwart von Nb-Katalysatoren |
DE102015005238A1 (de) | 2015-04-24 | 2016-10-27 | Wolfgang Hölderich | Herstellung von Lactamen durch Beckmann-Umlagerung von Oximen |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2245129A (en) * | 1935-01-02 | 1941-06-10 | Du Pont | Process for preparing linear polyamides |
US2301964A (en) * | 1941-09-12 | 1942-11-17 | Du Pont | Method of preparing lactams |
GB1121109A (en) * | 1964-09-03 | 1968-07-24 | Electro Chimie Metal | Improvements in or relating to preparation of epsilon-caprolactams |
FR2029540A1 (en) * | 1969-01-28 | 1970-10-23 | Asahi Chemical Ind | Epsilon caprolactam by one step synthesis |
DE4319134A1 (de) * | 1993-06-09 | 1994-12-15 | Basf Ag | Verfahren zur Herstellung von Caprolactam |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2357484A (en) * | 1941-09-12 | 1944-09-05 | Du Pont | Process for producing compounds containing an n-substituted amide group |
-
1994
- 1994-11-25 DE DE4441962A patent/DE4441962A1/de not_active Withdrawn
- 1994-12-19 US US08/358,411 patent/US5495016A/en not_active Expired - Fee Related
-
1995
- 1995-11-14 KR KR1019970703492A patent/KR100403093B1/ko not_active IP Right Cessation
- 1995-11-14 CN CN95196400A patent/CN1070182C/zh not_active Expired - Fee Related
- 1995-11-14 JP JP8518123A patent/JPH10509963A/ja not_active Withdrawn
- 1995-11-14 RU RU97110061/04A patent/RU2153492C2/ru not_active IP Right Cessation
- 1995-11-14 ES ES95937070T patent/ES2179888T3/es not_active Expired - Lifetime
- 1995-11-14 AT AT95937070T patent/ATE220061T1/de not_active IP Right Cessation
- 1995-11-14 PL PL95320367A patent/PL320367A1/xx unknown
- 1995-11-14 AU AU39287/95A patent/AU3928795A/en not_active Abandoned
- 1995-11-14 WO PCT/EP1995/004464 patent/WO1996016936A1/de active IP Right Grant
- 1995-11-14 MX MX9703727A patent/MX9703727A/es unknown
- 1995-11-14 DE DE59510263T patent/DE59510263D1/de not_active Expired - Lifetime
- 1995-11-14 EP EP95937070A patent/EP0793650B1/de not_active Expired - Lifetime
- 1995-11-14 CZ CZ19971469A patent/CZ291034B6/cs not_active IP Right Cessation
- 1995-11-24 MY MYPI95003607A patent/MY112192A/en unknown
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2245129A (en) * | 1935-01-02 | 1941-06-10 | Du Pont | Process for preparing linear polyamides |
US2301964A (en) * | 1941-09-12 | 1942-11-17 | Du Pont | Method of preparing lactams |
GB1121109A (en) * | 1964-09-03 | 1968-07-24 | Electro Chimie Metal | Improvements in or relating to preparation of epsilon-caprolactams |
FR2029540A1 (en) * | 1969-01-28 | 1970-10-23 | Asahi Chemical Ind | Epsilon caprolactam by one step synthesis |
DE4319134A1 (de) * | 1993-06-09 | 1994-12-15 | Basf Ag | Verfahren zur Herstellung von Caprolactam |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1999047500A1 (de) * | 1998-03-18 | 1999-09-23 | Basf Aktiengesellschaft | Verfahren zur herstellung von lactamen mit hilfe von oligophosphat-katalysatoren |
US6407230B1 (en) | 1998-03-18 | 2002-06-18 | Basf Aktiengesellschaft | Method for producing lactams using oligophosphate catalysts |
Also Published As
Publication number | Publication date |
---|---|
KR100403093B1 (ko) | 2004-03-18 |
AU3928795A (en) | 1996-06-19 |
US5495016A (en) | 1996-02-27 |
CN1070182C (zh) | 2001-08-29 |
PL320367A1 (en) | 1997-09-29 |
DE4441962A1 (de) | 1996-05-30 |
ATE220061T1 (de) | 2002-07-15 |
CN1166830A (zh) | 1997-12-03 |
ES2179888T3 (es) | 2003-02-01 |
DE59510263D1 (de) | 2002-08-08 |
MY112192A (en) | 2001-04-30 |
EP0793650A1 (de) | 1997-09-10 |
JPH10509963A (ja) | 1998-09-29 |
CZ146997A3 (en) | 1997-10-15 |
RU2153492C2 (ru) | 2000-07-27 |
MX9703727A (es) | 1998-02-28 |
EP0793650B1 (de) | 2002-07-03 |
CZ291034B6 (cs) | 2002-12-11 |
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