US20020055661A1 - Method for the production of bis(4-hydroxyaryl)-alkanes - Google Patents
Method for the production of bis(4-hydroxyaryl)-alkanes Download PDFInfo
- Publication number
- US20020055661A1 US20020055661A1 US10/037,995 US3799502A US2002055661A1 US 20020055661 A1 US20020055661 A1 US 20020055661A1 US 3799502 A US3799502 A US 3799502A US 2002055661 A1 US2002055661 A1 US 2002055661A1
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- United States
- Prior art keywords
- inert gas
- bis
- aromatic hydroxy
- hydroxyaryl
- alkanes
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- 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
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/68—Purification; separation; Use of additives, e.g. for stabilisation
- C07C37/70—Purification; separation; Use of additives, e.g. for stabilisation by physical treatment
Definitions
- the present invention relates to a process for producing bis(4-hydroxy-aryl)alkanes from addition products of bis(4-hydroxy-aryl)alkanes and aromatic hydroxy compounds which are obtained by the acid-catalysed reaction of aromatic hydroxy compounds with ketones.
- this addition product still contains traces of acid (about 5 to 10.10 ⁇ 6 mol acid/mol BPA) due to the acid-catalysed production route employed.
- these traces of acid result in the partial decomposition of the bisphenol and in the formation of by-products.
- the consequence of these decomposition reactions is an impairment of the purity and quality of colour of the bisphenol.
- This also has a negative effect on the quality of products produced from the bisphenols, such as epoxy resins, polyesters, polyester carbonates and polycarbonates, the consequences of which are problems of colour, poor transmission of light through transparent products, or pinholes in the surfaces of mouldings produced from these end products. Similar phenomena also occur during the production of other bis(4-hydroxyaryl)alkanes.
- the addition products of bis( 4 -hydroxyaryl)alkanes and aromatic hydroxy compounds which can be used in the process according to the invention can be obtained by the reaction of aromatic hydroxy compounds which are not substituted in the p-position and which contain no second order substituents such as cyano, carboxy or nitro groups, for example phenol, o- and m-cresol, 2,6-dimethylphenol, o-tert.-butyl phenol, 2-methyl-6-tert.-butylphenol, o-cyclohexylphenol, o-phenylphenol, o-isopropylphenol, 2-methyl-6-cyclopentyl-phenol, o- and m-chlorophenol, 2,3,6-trimethylphenol, preferably phenol, o- and m-cresol, 2,6-dimethylphenol, o-tert.-butylphenol and o-phenyl-phenol, most preferably phenol, with ketones which comprise at least one aliphatic group on
- hydroisophorone preferably acetone, acetophenone, cyclohexanone and homologues thereof which contain methyl groups, most preferably acetone.
- the addition product of bisphenol A and phenol is preferably used as a starting material.
- the present invention thus relates to a process for producing bis(4-hydroxyaryl)alkanes from addition products of bis(4-hydroxyaryl)alkanes and aromatic hydroxy compounds, wherein
- an inert gas is passed through a melt of an addition product of a bis(4-hydroxyaryl)alkane and an aromatic hydroxy compound at 150° C. to 230° C., wherein the inert gas stream removes the aromatic hydroxy compound from the melt,
- step a) the inert gas stream is purified, compressed and recycled to step a).
- Separation of the monophenol from the bis(4-hydroxyaryl)alkane from the melt of the addition product of bis(4-hydroxyaryl)alkane and aromatic hydroxy compound is effected at temperatures between 150° C. and 230° C., preferably from 170° C. to 210° C., by expelling the monophenol by the introduction of an inert gas (e.g. nitrogen).
- the ratio of gas to the amount of addition product is preferably about 10 m 3 to 1000 m 3 per tonne of addition product.
- Stripping can optionally be facilitated by reducing the pressure in the processing unit which is used for the separation of the monophenol, but is preferably effected under normal pressure. Stripping of the monophenol by the inert gas is conducted in known apparatuses, for example in a packed, flooded column.
- the monophenol can be removed from the inert gas circulation system, for example, by condensation on a heat exchanger.
- Purification of the recirculated inert gas can be effected by passing it over a fixed bed adsorbent (activated carbon, zeolite etc.), or in one preferred embodiment can be effected by intensively scrubbing the inert gas. This scrubbing step can be effected in a gas scrubber for example. In one preferred embodiment, during the compression of the inert gas of the circulating flow in a compressor the sealing liquid which is employed there is used as the scrubbing medium.
- a slightly alkaline aqueous solution is used as the scrubbing medium.
- the pH of the aqueous solution which is used should fall within the range from 7 to 12, preferably from 7.5 to 11, most preferably from 8 to 10. All substances which exhibit a basic effect can be used for the production of an aqueous solution such as this. Alkali and alkaline earth hydroxides are preferred.
- the pH is monitored before and after scrubbing, so that excessive and insufficient additions are prevented during the purification of the circulating gas circuit.
- the inert gas stream can subsequently be fed to a second scrubbing step.
- the second scrubbing medium preferably has a neutral pH.
- the bis(4-hydroxyaryl)alkanes which are produced by the process according to the invention are distinguished by their very good inherent colour and by their high purity.
- they comprise low contents of aromatic hydroxy compounds ( ⁇ 100 ppm, preferably ⁇ 50 ppm) and of decomposition products (e.g. isopropenylphenol, dimeric isopropenylphenol).
- Polymers such as polycarbonates or epoxides which exhibit a low degree of inherent colour can be manufactured from bis(4-hydroxyaryl)-alkanes which are produced by the process according to the invention.
- a molten mixture of BPA and phenol (60/40% by weight) was fed into a desorber at a rate of 1 tonne/hour. 225 m 3 /hour of nitrogen (as a circulating flow) were passed continuously into the desorber. The phenol was taken up by the nitrogen and was subsequently condensed by means of a heat exchanger. The nitrogen was subsequently fed to a compressor, the sealing liquid of which was acted upon by very dilute NaOH solution (pH 10), where the nitrogen was compressed. The nitrogen was then introduced into a gas scrubber which was operated using deionized water. The nitrogen which was treated in this manner was then reused in the desorber for the stripping of phenol. A low-phenol (phenol content 40 ppm), light-coloured BPA melt was then obtained, which had a melt Hazen colour of 8.
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
A process for producing bis(4-hydroxyaryl)alkane is disclosed. The process comprise in sequence the steps of (a) passing inert gas through a melt at 150 to 230° C. that contains bis(4-hydroxyaryl)alkane and other aromatic hydroxy compounds, under conditions designed to remove said other aromatic hydroxy compounds from said melt and to obtain a stream of inert gas that contains said other aromatic hydroxy compounds (b) condensing the stream obtained in (a) to remove said other aromatic hydroxy compound, and to obtain a stream of inert gas, and (c) purifying and compressing the stream of inert gas obtained in (b), and recycling to step (a).
Description
- The present invention relates to a process for producing bis(4-hydroxy-aryl)alkanes from addition products of bis(4-hydroxy-aryl)alkanes and aromatic hydroxy compounds which are obtained by the acid-catalysed reaction of aromatic hydroxy compounds with ketones.
- The synthesis of bis(4-hydroxyaryl)alkanes by the acid-catalysed reaction of aromatic hydroxy compounds with ketones is known from U.S. Pat. No. 2,775,620 or EP-A 342 758 for example. As a rule, an addition product of the bis(4-hydroxyaryl)alkane and of the aromatic hydroxy compound which is used as a starting material is obtained as an intermediate, and is subsequently freed from the aromatic hydroxy compound by distillation. The most important example of large-scale industrial production is the production of bisphenol A, during which an addition product of bisphenol A (BPA) and phenol is obtained as an intermediate. Even after purification, by recrystallisation for example, this addition product still contains traces of acid (about 5 to 10.10−6 mol acid/mol BPA) due to the acid-catalysed production route employed. On the separation of the phenol from bisphenol A, which is associated with an increase in temperature, these traces of acid result in the partial decomposition of the bisphenol and in the formation of by-products. The consequence of these decomposition reactions is an impairment of the purity and quality of colour of the bisphenol. This also has a negative effect on the quality of products produced from the bisphenols, such as epoxy resins, polyesters, polyester carbonates and polycarbonates, the consequences of which are problems of colour, poor transmission of light through transparent products, or pinholes in the surfaces of mouldings produced from these end products. Similar phenomena also occur during the production of other bis(4-hydroxyaryl)alkanes.
- The separation of the aromatic hydroxy compound, which is also termed “stripping”, from the bis(4-hydroxyaryl)alkane, is known from the literature and is described in EP-A 343 349 for example. The aromatic hydroxy compound is separated from the bis(4-hydroxyaryl)alkane here by employing steam in a packed column at 160 to 200° C. under a slightly reduced pressure. It is also known, e.g. from U.S. Pat. No. 5,091,159, that thermal decomposition reactions occur during the separation of the aromatic hydroxy compound from the bis(4-hydroxyaryl)alkane.
- A process has now been found which strongly suppresses decomposition reactions during the stripping of the aromatic hydroxy compound (“monophenol”) from the bis(4-hydroxyaryl)-alkane. On the separation of the monophenol from the bis(4-hydroxyaryl)alkane with inert gas in the course of this process, the recycled inert gas is purified after the condensation of the monophenol, so that degradation of the bis(4-hydroxyaryl)alkane can be avoided.
- The addition products of bis(4-hydroxyaryl)alkanes and aromatic hydroxy compounds which can be used in the process according to the invention can be obtained by the reaction of aromatic hydroxy compounds which are not substituted in the p-position and which contain no second order substituents such as cyano, carboxy or nitro groups, for example phenol, o- and m-cresol, 2,6-dimethylphenol, o-tert.-butyl phenol, 2-methyl-6-tert.-butylphenol, o-cyclohexylphenol, o-phenylphenol, o-isopropylphenol, 2-methyl-6-cyclopentyl-phenol, o- and m-chlorophenol, 2,3,6-trimethylphenol, preferably phenol, o- and m-cresol, 2,6-dimethylphenol, o-tert.-butylphenol and o-phenyl-phenol, most preferably phenol, with ketones which comprise at least one aliphatic group on their carbonyl function, for example acetone, methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, diethyl ketone, acetophenone, cyclohexanone, cyclopentanone, and methyl-, dimethyl- and trimethylcyclohexanones which may also contain geminal methyl groups e.g. 3,3-di-methyl-5-methylcyclohexanone (hydroisophorone), preferably acetone, acetophenone, cyclohexanone and homologues thereof which contain methyl groups, most preferably acetone. The addition product of bisphenol A and phenol is preferably used as a starting material.
- The present invention thus relates to a process for producing bis(4-hydroxyaryl)alkanes from addition products of bis(4-hydroxyaryl)alkanes and aromatic hydroxy compounds, wherein
- a) an inert gas is passed through a melt of an addition product of a bis(4-hydroxyaryl)alkane and an aromatic hydroxy compound at 150° C. to 230° C., wherein the inert gas stream removes the aromatic hydroxy compound from the melt,
- b) the aromatic hydroxy compound is removed from the inert gas stream by condensation,
- c) the inert gas stream is purified, compressed and recycled to step a).
- Separation of the monophenol from the bis(4-hydroxyaryl)alkane from the melt of the addition product of bis(4-hydroxyaryl)alkane and aromatic hydroxy compound is effected at temperatures between 150° C. and 230° C., preferably from 170° C. to 210° C., by expelling the monophenol by the introduction of an inert gas (e.g. nitrogen). The ratio of gas to the amount of addition product is preferably about 10 m3 to 1000 m3 per tonne of addition product. Stripping can optionally be facilitated by reducing the pressure in the processing unit which is used for the separation of the monophenol, but is preferably effected under normal pressure. Stripping of the monophenol by the inert gas is conducted in known apparatuses, for example in a packed, flooded column. The monophenol can be removed from the inert gas circulation system, for example, by condensation on a heat exchanger.
- Purification of the recirculated inert gas can be effected by passing it over a fixed bed adsorbent (activated carbon, zeolite etc.), or in one preferred embodiment can be effected by intensively scrubbing the inert gas. This scrubbing step can be effected in a gas scrubber for example. In one preferred embodiment, during the compression of the inert gas of the circulating flow in a compressor the sealing liquid which is employed there is used as the scrubbing medium.
- A slightly alkaline aqueous solution is used as the scrubbing medium. The pH of the aqueous solution which is used should fall within the range from 7 to 12, preferably from 7.5 to 11, most preferably from 8 to 10. All substances which exhibit a basic effect can be used for the production of an aqueous solution such as this. Alkali and alkaline earth hydroxides are preferred. In one preferred embodiment, the pH is monitored before and after scrubbing, so that excessive and insufficient additions are prevented during the purification of the circulating gas circuit. Moreover, the inert gas stream can subsequently be fed to a second scrubbing step. The second scrubbing medium preferably has a neutral pH.
- The bis(4-hydroxyaryl)alkanes which are produced by the process according to the invention are distinguished by their very good inherent colour and by their high purity. In particular, they comprise low contents of aromatic hydroxy compounds (<100 ppm, preferably <50 ppm) and of decomposition products (e.g. isopropenylphenol, dimeric isopropenylphenol).
- Polymers such as polycarbonates or epoxides which exhibit a low degree of inherent colour can be manufactured from bis(4-hydroxyaryl)-alkanes which are produced by the process according to the invention.
- A molten mixture of BPA and phenol (60/40% by weight) was fed into a desorber at a rate of 1 tonne/hour. 225 m3/hour of nitrogen (as a circulating flow) were passed continuously into the desorber. The phenol was taken up by the nitrogen and was subsequently condensed by means of a heat exchanger. The nitrogen was subsequently fed to a compressor, the sealing liquid of which was acted upon by very dilute NaOH solution (pH 10), where the nitrogen was compressed. The nitrogen was then introduced into a gas scrubber which was operated using deionized water. The nitrogen which was treated in this manner was then reused in the desorber for the stripping of phenol. A low-phenol (phenol content 40 ppm), light-coloured BPA melt was then obtained, which had a melt Hazen colour of 8.
- The procedure was as in Example 1, except that scrubbing of the nitrogen was completely omitted. A BPA was then obtained which had a Hazen colour of 17. The phenol content of the BPA was 90 ppm, which indicated decomposition.
- The procedure was as in Example 1, except that neutral deionised water (pH 6.9) was used for scrubbing the nitrogen. A BPA was then obtained which had a Hazen colour of 14. The phenol content of the BPA was 75 ppm, which again indicated decomposition.
- The procedure was as in Example 1, except that a dilute NaOH solution (pH 13) was used for scrubbing the nitrogen. A BPA was then obtained which had a Hazen colour of 12. The phenol content of the BPA was 60 ppm, which still indicated decomposition.
Claims (7)
1. A process for producing bis(4-hydroxyaryl)alkanes from addition products of bis(4-hydroxyaryl)alkanes and aromatic hydroxy compounds, wherein
a) an inert gas is passed through a melt of an addition product of a bis(4-hydroxy-aryl)alkane and an aromatic hydroxy compound at 150° C. to 230° C., wherein the inert gas stream removes the aromatic hydroxy compound from the melt,
b) the aromatic hydroxy compound is removed from the inert gas stream by condensation,
c) the inert gas stream is purified, compressed and recycled to step a).
2. A process according to claim 1 , wherein purification of the inert gas stream is effected by scrubbing with an aqueous medium with a pH within the range from 7 to 12.
3. A process according to claim 2 , wherein the sealing liquid of the compressor used for the compression of the inert gas is employed as the scrubbing medium.
4. A process according to claims 2 or 3, wherein after alkaline scrubbing and before it is recycled to step a) the inert gas stream is subjected to a second scrubbing step in an aqueous medium of neutral pH.
5. A process according to claim 1 , wherein purification of the inert gas stream is effected by passing it over a fixed bed adsorbent.
6. A process according to claim 5 , wherein activated carbon or zeolite is used as the fixed bed adsorbent.
7. Bis(4-hydroxy)alkanes with a content of aromatic hydroxy compounds of <50 ppm, obtainable by a process according to claim 1.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/037,995 US20020055661A1 (en) | 1998-10-17 | 2002-01-03 | Method for the production of bis(4-hydroxyaryl)-alkanes |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19848026.1 | 1998-10-17 | ||
DE19848026A DE19848026A1 (en) | 1998-10-17 | 1998-10-17 | Production of bis(4-hydroxyaryl)alkane, useful in production of polymer, e.g. polycarbonate or epoxide, involves using circulating inert gas for stripping aromatic hydroxyl compound from adduct |
US09/807,645 US6384288B1 (en) | 1998-10-17 | 1999-10-05 | Method for the production of bis(4-hydroxyaryl)alkanes |
US10/037,995 US20020055661A1 (en) | 1998-10-17 | 2002-01-03 | Method for the production of bis(4-hydroxyaryl)-alkanes |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US09/807,645 Division US6384288B1 (en) | 1998-10-17 | 1999-10-05 | Method for the production of bis(4-hydroxyaryl)alkanes |
Publications (1)
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US20020055661A1 true US20020055661A1 (en) | 2002-05-09 |
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ID=7884875
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
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US09/807,645 Expired - Lifetime US6384288B1 (en) | 1998-10-17 | 1999-10-05 | Method for the production of bis(4-hydroxyaryl)alkanes |
US10/037,995 Abandoned US20020055661A1 (en) | 1998-10-17 | 2002-01-03 | Method for the production of bis(4-hydroxyaryl)-alkanes |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
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US09/807,645 Expired - Lifetime US6384288B1 (en) | 1998-10-17 | 1999-10-05 | Method for the production of bis(4-hydroxyaryl)alkanes |
Country Status (14)
Country | Link |
---|---|
US (2) | US6384288B1 (en) |
EP (1) | EP1121339B1 (en) |
JP (1) | JP2002527497A (en) |
KR (1) | KR100608922B1 (en) |
CN (1) | CN1173911C (en) |
AU (1) | AU6089399A (en) |
BR (1) | BR9914607A (en) |
DE (2) | DE19848026A1 (en) |
ES (1) | ES2190253T3 (en) |
HK (1) | HK1042080A1 (en) |
ID (1) | ID29771A (en) |
MD (1) | MD2705B2 (en) |
TW (1) | TW517046B (en) |
WO (1) | WO2000023410A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080067544A1 (en) * | 2004-09-30 | 2008-03-20 | Siegfried Mantl | Method for Producing a Strained Layer on a Substrate and Layered Structure |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3340510B2 (en) * | 1993-05-19 | 2002-11-05 | 日本パイオニクス株式会社 | Hazardous gas purification method |
DE19961566A1 (en) | 1999-12-20 | 2001-06-21 | Bayer Ag | Use of a desorber with optionally series-connected distillation unit for separation of bis-phenol, e.g. Bisphenol A, and phenol from adducts of bis-phenol and phenol |
US6703530B2 (en) | 2002-02-28 | 2004-03-09 | General Electric Company | Chemical reactor system and process |
JP2007513250A (en) * | 2003-12-03 | 2007-05-24 | イー・アイ・デュポン・ドウ・ヌムール・アンド・カンパニー | Products containing rigid and elastic ethylene copolymer compositions |
DK3718564T3 (en) | 2003-12-23 | 2023-11-06 | Genentech Inc | Novel anti-IL-13 antibodies and applications |
DE102005025788A1 (en) | 2005-06-04 | 2006-12-07 | Bayer Materialscience Ag | Process for the preparation of high purity bisphenol A |
US7754837B1 (en) | 2007-03-09 | 2010-07-13 | Clemson University Research Foundation | Flourinated aryl ether polymers exhibiting dual fluoroolefin functionality and methods of forming same |
DE102007026548A1 (en) | 2007-06-08 | 2008-12-18 | Bayer Materialscience Ag | Prevention of solid deposits in mist eliminators by injection of suitable liquids |
EP4163633A1 (en) | 2013-09-13 | 2023-04-12 | F. Hoffmann-La Roche AG | Compositions and methods for detecting and quantifying host cell protein in cell lines and recombinant polypeptide products |
CA2921999C (en) | 2013-09-13 | 2023-03-21 | Genentech, Inc. | Methods and compositions comprising an anti-il13 antibody and residual hamster phospholipase b-like 2 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2775620A (en) * | 1954-07-12 | 1956-12-25 | Shell Dev | Production of bis (hydroxyaryl) substituted compounds |
US4931146A (en) * | 1988-04-05 | 1990-06-05 | Mitsui Toatsu Chemicals, Inc. | Process for obtaining high-purity bisphenol A |
US4859803A (en) * | 1988-05-16 | 1989-08-22 | Shell Oil Company | Preparation of bisphenols |
US5091159A (en) | 1991-06-10 | 1992-02-25 | Nalco Chemical Company | Use of dextran as a filtration aid for thickener overflow filtration in Kelly filters in the Bayer process |
CN1050828C (en) * | 1993-02-16 | 2000-03-29 | 中国石油化工总公司 | Method of dephenolization for preparing high quality polycarbonic ester grade bisphenol A |
CN1080914A (en) * | 1993-02-17 | 1994-01-19 | 中国石油化工总公司 | A kind of 2, the manufacture method of 2-two (4-hydroxy phenyl) propane |
-
1998
- 1998-10-17 DE DE19848026A patent/DE19848026A1/en not_active Ceased
-
1999
- 1999-10-01 TW TW088116896A patent/TW517046B/en not_active IP Right Cessation
- 1999-10-05 BR BR9914607-0A patent/BR9914607A/en not_active IP Right Cessation
- 1999-10-05 AU AU60893/99A patent/AU6089399A/en not_active Abandoned
- 1999-10-05 ES ES99947458T patent/ES2190253T3/en not_active Expired - Lifetime
- 1999-10-05 DE DE59904188T patent/DE59904188D1/en not_active Expired - Lifetime
- 1999-10-05 EP EP99947458A patent/EP1121339B1/en not_active Expired - Lifetime
- 1999-10-05 MD MDA20010161A patent/MD2705B2/en unknown
- 1999-10-05 ID IDW20010848A patent/ID29771A/en unknown
- 1999-10-05 KR KR1020017004787A patent/KR100608922B1/en not_active IP Right Cessation
- 1999-10-05 JP JP2000577138A patent/JP2002527497A/en active Pending
- 1999-10-05 US US09/807,645 patent/US6384288B1/en not_active Expired - Lifetime
- 1999-10-05 CN CNB998122572A patent/CN1173911C/en not_active Expired - Fee Related
- 1999-10-05 WO PCT/EP1999/007358 patent/WO2000023410A1/en active IP Right Grant
-
2002
- 2002-01-03 US US10/037,995 patent/US20020055661A1/en not_active Abandoned
- 2002-05-15 HK HK02103685.2A patent/HK1042080A1/en unknown
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080067544A1 (en) * | 2004-09-30 | 2008-03-20 | Siegfried Mantl | Method for Producing a Strained Layer on a Substrate and Layered Structure |
US8048220B2 (en) * | 2004-09-30 | 2011-11-01 | Forschungszentrum Julich Gmbh | Method for producing a strained layer on a substrate and layered structure |
Also Published As
Publication number | Publication date |
---|---|
US6384288B1 (en) | 2002-05-07 |
ES2190253T3 (en) | 2003-07-16 |
KR20010080188A (en) | 2001-08-22 |
MD2705B2 (en) | 2005-02-28 |
JP2002527497A (en) | 2002-08-27 |
CN1173911C (en) | 2004-11-03 |
EP1121339A1 (en) | 2001-08-08 |
TW517046B (en) | 2003-01-11 |
CN1323285A (en) | 2001-11-21 |
AU6089399A (en) | 2000-05-08 |
MD20010161A (en) | 2001-09-30 |
HK1042080A1 (en) | 2002-08-02 |
EP1121339B1 (en) | 2003-01-29 |
ID29771A (en) | 2001-10-11 |
KR100608922B1 (en) | 2006-08-04 |
BR9914607A (en) | 2001-07-03 |
DE59904188D1 (en) | 2003-03-06 |
DE19848026A1 (en) | 2000-04-20 |
WO2000023410A1 (en) | 2000-04-27 |
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