WO2008098581A1 - A continuous process for the preparation of alkyl esters of lactic acid and aliphatic alcohols - Google Patents
A continuous process for the preparation of alkyl esters of lactic acid and aliphatic alcohols Download PDFInfo
- Publication number
- WO2008098581A1 WO2008098581A1 PCT/EE2007/000002 EE2007000002W WO2008098581A1 WO 2008098581 A1 WO2008098581 A1 WO 2008098581A1 EE 2007000002 W EE2007000002 W EE 2007000002W WO 2008098581 A1 WO2008098581 A1 WO 2008098581A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- lactic acid
- process according
- alcohol
- alkyl esters
- moles
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/03—Preparation of carboxylic acid esters by reacting an ester group with a hydroxy group
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
Definitions
- the present invention relates to a continuous process for the preparation of alkyl ester hydroxycarboxyiic acids.
- the present invention particularly relates to a catalytic process for the conversion of mixtures containing free lactic acid and/or dimers and/or highpolymers of lactic acids and its alkyl esters to alkyl esters of aliphatic alcohols by contact of its mixtures with aliphatic alcohols.
- lactic acid esters can advantageously be taken advantage of in numerous fields of activity, such as the metal industries, the automobile and aviation industries, the paint and ink industries, the resin and varnish industries, the pharmaceutical and cosmetological industries, and the semiconductor industries.
- esters of lactic acid remains to this day a product which is still not manufactured and used industrially to any great extent, in particular with regard to chlorinated solvents, glycols or glycol ethers, because of their price, which in two - four times above than the price of the main commercially accessible glycol ethers.
- US 5264617 (DU PONT) 23.11.1993 reports synthesis of lactic acid esters in the presence of a catalyst (p-toluene sulfonic acid) by depolymerization of polylactide by heating with a Ci to Ce alkyl alcohol in an amount of 1-3 mole of alcohol per hydroxy acid equivalent. Yield of lactic acid esters is 87%.
- a catalyst p-toluene sulfonic acid
- a continues process for manufacture of ethyl lactate by catalytic rectifying method is described in a patent CN 1613842 (UNIV TSINGHUA) 11.05.2005 . It is carried out by lactic acid catalytic reacting with alcohol (3-5 mole of ethanol per mole of lactic acid) in catalytic section of catalytic rectifying tower with highly acid ionic exchanging resin as a catalyst, generating ethyl lactate, vaporizing alcohol in reacting solution and generated water, enriching in rectifying section of rectifying tower, alcohol and water condensing in condenser, one part returning feed storing tank, another part back flowing into catalytic rectifying tower.
- alcohol 3-5 mole of ethanol per mole of lactic acid
- the main object of the present invention is to provide a process continues esterification of lactic acid, dimers, oligomers, polymers and its esters for the preparation of alkyl esters.
- One embodiment of the present invention is shown in Fig. 1, and includes reactor I, mixer IV, vessel III and throttling device II.
- the reaction may be catalyzed by one or more of a number of methods.
- a heterogeneous catalyst may be retained at tubes of reactor I.
- Homogeneous catalyst may be loaded in the vessel III and circulates on a line: vessel III - mixer IV - reactor I - vessel III.
- the reaction can carry out in the absence of the catalyst, but in this case a high temperature is required.
- the mixture of free lactic acid, oligomers and/or polymers, its alkyl esters, alcohol and homogeneous catalyst is loaded into a vessel III and circulated via (4) through heated reactor I approximately within 3-7 hours.
- a vaporous of crude ester continuously is drawn off from the vessel III according to a level of a liquid phase at a vessel III.
- a vaporous of crude ester is condensed and to distill.
- the crude esters are essentially free from water and alcohol.
- FIG. 2 Other embodiment of the present invention is shown in FIG. 2, and includes reactor I, mixers IV and VII, column Il and V, and vessel III.
- a heterogeneous catalyst may be retained at tubes of reactor I.
- Homogeneous catalyst may be loaded into the still of column Il and circulates on a line: column Il - mixer IV - vessel III - (reactor I) - column V - mixer IV - column II.
- a vaporous of crude ester continuously is drawn off from the vessel Ul according to a level of a liquid phase at the vessel III, is condensed and is analyzed by GLC analysis.
- the condensate (flow 3, approximate 14.6 g/h) has the following composition, %wt: Methyl Lactate -96.3; Methanol - 1.9; Water- 1.8.
- the yield of methyl lactate is 99.8%.
- the tubes of reactor I was charged with of the heterogeneous catalyst (Nafion-H). 200 g oligomers of lactic acid with the mean degree of polymerization (MDP) equal to 10, 65 g butanol, 60 g butyl lactate and 1.0g tin(ll) 2-ethylhexanoate are loaded into the vessel III. A resulting mixture circulated via (4) (approximate 86.7 g/h) through the heated reactor I (145 0 C) approximately within 7 hours.
- MDP mean degree of polymerization
- the condensate of column 5 (approximate 19.8 g/h) has the following composition, %wt.: Butyl Lactate -95.5; Butanol - 3.0; Water -1.5. The yield of Butyl lactate is 99.5%.
- the condensate of column 2 (approximate 2.3 g/h) has the following composition %wt.: Lactic acid - 2; Butanol - 2; Butyl Lactate - 1 ; Water - 95.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The present invention relates to a continuous processes for producing of alkyl esters of lactic acid by reaction of lactic acid, oligomers or/and polymers and its alkyl esters with alcohol. The present method is characterized by that process is carried out in a solution of a target product at mole ratio alcohol/lactic acid, oligomers or/and polymers and its alkyl esters at an initial mix less 1.
Description
Description
A continuous process for the preparation of alkyl esters of lactic acid and aliphatic alcohols
Technical Field
[0001] The present invention relates to a continuous process for the preparation of alkyl ester hydroxycarboxyiic acids. The present invention particularly relates to a catalytic process for the conversion of mixtures containing free lactic acid and/or dimers and/or highpolymers of lactic acids and its alkyl esters to alkyl esters of aliphatic alcohols by contact of its mixtures with aliphatic alcohols.
Background Art
[0002] The industrial use of solvents such as chlorinated solvents, glycols and glycol ethers is being increasingly called into question because of the toxicity of these products and their negative effect on the environment. There is therefore a search to substitute them by "green" solvents, namely biodegradable and nontoxic solvents, such as lactic acid esters. Esters possess a number of physical and chemical properties which allow to replace all or some of usual solvents:
- an excellent solvating power for resins (nitrocellulose, acrylic resins, polyurethanes, polyesters, alkyds, epoxy, and the like),
- a relatively high solubility in water and a generally good solubility in the majority of organic solvents,
- a relatively low volatility, allowing, for example, its effective use in surface treatment applications,
- a relatively high boiling point, allowing its effective use in applications involving high temperatures.
[0003] The properties of lactic acid esters can advantageously be taken advantage of in numerous fields of activity, such as the metal industries, the automobile and aviation industries, the paint and ink industries, the resin and varnish industries, the pharmaceutical and cosmetological industries, and the semiconductor industries.
[0004] Despite of their undeniable advantage, esters of lactic acid remains to this day a product which is still not manufactured and used industrially to any
great extent, in particular with regard to chlorinated solvents, glycols or glycol ethers, because of their price, which in two - four times above than the price of the main commercially accessible glycol ethers.
[0005] US 5264617 (DU PONT) 23.11.1993 reports synthesis of lactic acid esters in the presence of a catalyst (p-toluene sulfonic acid) by depolymerization of polylactide by heating with a Ci to Ce alkyl alcohol in an amount of 1-3 mole of alcohol per hydroxy acid equivalent. Yield of lactic acid esters is 87%.
[0006] A continues process for manufacture of ethyl lactate by catalytic rectifying method is described in a patent CN 1613842 (UNIV TSINGHUA) 11.05.2005 . It is carried out by lactic acid catalytic reacting with alcohol (3-5 mole of ethanol per mole of lactic acid) in catalytic section of catalytic rectifying tower with highly acid ionic exchanging resin as a catalyst, generating ethyl lactate, vaporizing alcohol in reacting solution and generated water, enriching in rectifying section of rectifying tower, alcohol and water condensing in condenser, one part returning feed storing tank, another part back flowing into catalytic rectifying tower.
[0007] A continues esterification of lactic acid with methanol (5 mole of methanol per mole of lactic acid) in the presence of acidic catalyst (HaSO4) at 30- 3000C and 0.01 to 30 bar is patented in DE 3222837 (HOECHST AG) 22.12.1983 . It is carried out in distillation column. At the head of the column to draw a distillate comprising of methyl lactate (39%), methanol (53%), water (7%) and lactic acid (1 %). Yield of methyl lactate 97,8 %.
[0008] US 2005096481 (HiLDEBRANDT RAINER ET AL.) 05.05.2005 patented a process for producing esters of a hydroxy acid and a Ci-Ce alcohol by reactive distillation on a heterogeneous catalyst. The catalyst is preferably fixed in the distillation column. The best results are reached when the entraining agent is used (heptane, diisopropyl ether). When the entraining agent is superfluity of alcohol, a by-product (alkyl ethers) is formed.
[0009] US 2003008927 (FUERTES PATRICK ET AL.) 09.01.2003 claims a process for preparing a lactic acid esters from a lactic acid composition comprising a stage of conversion lactic acid into a lactic acid oligomeric composition having a mean degree of polymerisation ranging between 2
and 30 approximately; a stage of mixing and reacting oligomeric composition with an alcohol, in the presence of a transesterification catalyst, to esterify all or part of the lactic acid contained in oligomeric composition. All examples of this method carry out by using of substantial excess corresponding alcohol. Disclosure of Invention [0010] The synthesis of a lactic acid esters in prior art is usually accomplished by using of substantial excess corresponding alcohol in the liquid phase.
Since the most part of alcohol remains in the final product, use a large number of energy resources for isolation of target product is necessary. [0011] Moreover, a number of alcohols and ethers form azeotropic mixtures with a water, it essentially complicates isolation of a target product. [0012] The main object of the present invention is to provide a process continues esterification of lactic acid, dimers, oligomers, polymers and its esters for the preparation of alkyl esters. [0013] One embodiment of the present invention is shown in Fig. 1, and includes reactor I, mixer IV, vessel III and throttling device II. [0014] The reaction may be catalyzed by one or more of a number of methods. A heterogeneous catalyst may be retained at tubes of reactor I.
Homogeneous catalyst may be loaded in the vessel III and circulates on a line: vessel III - mixer IV - reactor I - vessel III. [0015] The reaction can carry out in the absence of the catalyst, but in this case a high temperature is required. [0016] The mixture of free lactic acid, oligomers and/or polymers, its alkyl esters, alcohol and homogeneous catalyst is loaded into a vessel III and circulated via (4) through heated reactor I approximately within 3-7 hours. [0017] After it begins continuous feeding alcohol (2) and mixture of lactic acid, oligomers or/and polymers (1) into mixer IV. A vaporous of crude ester continuously is drawn off from the vessel III according to a level of a liquid phase at a vessel III. A vaporous of crude ester is condensed and to distill.
The crude esters are essentially free from water and alcohol. [0018] Other embodiment of the present invention is shown in FIG. 2, and includes reactor I, mixers IV and VII, column Il and V, and vessel III.
[0019] A heterogeneous catalyst may be retained at tubes of reactor I.
Homogeneous catalyst may be loaded into the still of column Il and circulates on a line: column Il - mixer IV - vessel III - (reactor I) - column V - mixer IV - column II.
[0020] The mixture of free lactic acid, oligomers and/or polymers, its alkyl esters, alcohol and homogeneous catalyst is loaded into the still of column Il and circulated approximately within 3-7 hours on a line: column Il - mixer IV - vessel III - (reactor I) - column V - mixer IV - column II. After it begins continuous feeding alcohol (2) into the mixer IV and lactic acid into mixer VII (1). At the head of the column Il essentially water is drawn off (5). One part of the liquid phase recycled via (4) into the mixer IV. Other part of the liquid phase feeds via (7) into column V according to a level of a liquid phase at the vessel III. The mixture of crude ester is drawn off continuously from the top of the column V. A heavy still bottoms recycled via (6) into mixer VII. The crude esters are essentially free from water and alcohol.
[0021] The following examples are given as an illustration and therefore should not be construed to limit the scope of the present invention. EXAMPLE 1
[0022] 200 g oligomers of lactic acid with the mean degree of polymerization (MDP) equal to 10, 35 g methanol, 60 g methyl lactate and 2.6g tetra-n- butoxytitanum are loaded into the vessel III. A resulting mixture is circulated (flow 4, approximate 76.2 g/h) through heated reactor I (17O0C) approximately within 4 hours. After it begins continuous feeding methanol (flow 2, approximate 4.6 g/h, 0.14 mol/h) and oligomers of lactic acid with the mean degree of polymerization (MDP) equal to 10 (flow 1, approximate 10.0 g/h) into the mixer IV. The mole ratio of methanol/oligomers (counting upon free lactic acid) in mixture fed into reactor I is equal to 0.12.
[0023] A vaporous of crude ester continuously is drawn off from the vessel Ul according to a level of a liquid phase at the vessel III, is condensed and is analyzed by GLC analysis. The condensate (flow 3, approximate 14.6 g/h) has the following composition, %wt: Methyl Lactate -96.3; Methanol - 1.9;
Water- 1.8. The yield of methyl lactate is 99.8%. EXAMPLE 2
[0024] The tubes of reactor I was charged with of the heterogeneous catalyst (Nafion-H). 200 g oligomers of lactic acid with the mean degree of polymerization (MDP) equal to 10, 65 g butanol, 60 g butyl lactate and 1.0g tin(ll) 2-ethylhexanoate are loaded into the vessel III. A resulting mixture circulated via (4) (approximate 86.7 g/h) through the heated reactor I (1450C) approximately within 7 hours.
[0025] Then it begins continuous feeding butanol via (2) (approximate 10.4 g/h, 0.14 mol/h) into mixer IV and of lactic acid via (1) (approximate 11.7 g/h, 0.13 mol/h) into mixer VII. At the same time it begins continuous feeding mixture via (7) from the vessel III to column V according to the level of a liquid phase at the vessel III, withdrawal of condensate from the column V via (3) and from the column Il via (5). A heavy still bottoms of column V via (6) is recycled to the mixer VII. The mole ratio of butanol/oligomers (counting upon free lactic acid) in mixture fed to reactor I is equal to 0.16.
[0026] The condensate of column 5 (approximate 19.8 g/h) has the following composition, %wt.: Butyl Lactate -95.5; Butanol - 3.0; Water -1.5. The yield of Butyl lactate is 99.5%.
[0027] The condensate of column 2 (approximate 2.3 g/h) has the following composition %wt.: Lactic acid - 2; Butanol - 2; Butyl Lactate - 1 ; Water - 95.
Claims
1. A continues process for the preparation of alkyl esters of lactic acid and aliphatic alcohols comprising a stage of:
- mixing an alcohol with a fluid flow, comprising of free lactic acid, oligomers or/and polymers and its alkyl esters;
- feeding said mix to a reactor;
- synthesis of a target product; wherein said mix is characterized by deficiency of moles an alcohol with respect to moles of lactic acid, oligomers or/and polymers and its alkyl esters.
2. A process according to claim 1 , wherein said alcohols are C1-C6 alcohols.
3. A process according to claim 1 , wherein a ratio of moles alcohol to moles of lactic acid in free and unfree form in said mix, no more than 0.95.
4. A process according to claim 1 , wherein a ratio of moles alcohol to moles of lactic acid in free and unfree form in said mix, no more than 0.3.
5. A process according to claim 1 , wherein synthesis is carried out at the presence of a heterogeneous and/or homogeneous catalyst.
6. A process according to claim 5, wherein a catalyst is Lewis acids.
7. A process according to claim 6, wherein a catalyst is an organic and/or inorganic compound of tin and/or titanium and/or zinc.
8. A process according to claim 1 , wherein a process includes a supplementary stage of conversion of lactic acid to it oligomers or/and polymers.
9. A process according to claim 1, wherein synthesis is carried out at the temperature above of the boiling point of target product under standard conditions.
10. A process according to claim 1 , wherein synthesis is carried out at pressure in the reactor, providing a presence of all components of a mix at a liquid phase.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP07702546A EP2121561A1 (en) | 2007-02-12 | 2007-02-12 | A continuous process for the preparation of alkyl esters of lactic acid and aliphatic alcohols |
| PCT/EE2007/000002 WO2008098581A1 (en) | 2007-02-12 | 2007-02-12 | A continuous process for the preparation of alkyl esters of lactic acid and aliphatic alcohols |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/EE2007/000002 WO2008098581A1 (en) | 2007-02-12 | 2007-02-12 | A continuous process for the preparation of alkyl esters of lactic acid and aliphatic alcohols |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2008098581A1 true WO2008098581A1 (en) | 2008-08-21 |
Family
ID=38567011
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/EE2007/000002 WO2008098581A1 (en) | 2007-02-12 | 2007-02-12 | A continuous process for the preparation of alkyl esters of lactic acid and aliphatic alcohols |
Country Status (2)
| Country | Link |
|---|---|
| EP (1) | EP2121561A1 (en) |
| WO (1) | WO2008098581A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018069372A1 (en) * | 2016-10-12 | 2018-04-19 | Basf Se | Method of preparing hydroxyalkylcarboxylic acid esters |
| CN108084021A (en) * | 2017-12-27 | 2018-05-29 | 上海应用技术大学 | A kind of preparation method of isobutyl palmitate |
| CN111943849A (en) * | 2020-08-15 | 2020-11-17 | 天津大学 | High-efficiency energy-saving ethyl lactate reaction rectification production method and device |
| RU2807294C1 (en) * | 2023-03-16 | 2023-11-13 | Федеральное государственное автономное образовательное учреждение высшего образования "Национальный исследовательский Томский политехнический университет" | Method of obtaining methyl lactate |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030008927A1 (en) * | 1999-12-28 | 2003-01-09 | Patrick Fuertes | Method for preparing a lactic acid ester composition and use thereof as solvent |
| US20060014976A1 (en) * | 2002-12-05 | 2006-01-19 | Georges Martino-Gauchi | Continuous method for preparing ethyl lactate |
-
2007
- 2007-02-12 WO PCT/EE2007/000002 patent/WO2008098581A1/en active Application Filing
- 2007-02-12 EP EP07702546A patent/EP2121561A1/en not_active Withdrawn
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030008927A1 (en) * | 1999-12-28 | 2003-01-09 | Patrick Fuertes | Method for preparing a lactic acid ester composition and use thereof as solvent |
| US20060014976A1 (en) * | 2002-12-05 | 2006-01-19 | Georges Martino-Gauchi | Continuous method for preparing ethyl lactate |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018069372A1 (en) * | 2016-10-12 | 2018-04-19 | Basf Se | Method of preparing hydroxyalkylcarboxylic acid esters |
| CN109843848A (en) * | 2016-10-12 | 2019-06-04 | 巴斯夫欧洲公司 | The method for preparing hydroxy alkyl carboxylic acid's ester |
| JP2019531313A (en) * | 2016-10-12 | 2019-10-31 | ビーエーエスエフ ソシエタス・ヨーロピアＢａｓｆ Ｓｅ | Process for preparing hydroxyalkyl carboxylic acid esters |
| AU2017341386B2 (en) * | 2016-10-12 | 2021-08-12 | Basf Se | Method of preparing hydroxyalkylcarboxylic acid esters |
| CN109843848B (en) * | 2016-10-12 | 2023-02-28 | 巴斯夫欧洲公司 | Method for producing hydroxyalkyl carboxylic acid esters |
| US11597695B2 (en) | 2016-10-12 | 2023-03-07 | Basf Se | Method of preparing hydroxyalkylcarboxylic acid esters |
| CN108084021A (en) * | 2017-12-27 | 2018-05-29 | 上海应用技术大学 | A kind of preparation method of isobutyl palmitate |
| CN111943849A (en) * | 2020-08-15 | 2020-11-17 | 天津大学 | High-efficiency energy-saving ethyl lactate reaction rectification production method and device |
| CN111943849B (en) * | 2020-08-15 | 2023-08-29 | 天津大学 | Efficient energy-saving ethyl lactate reactive distillation production method and device |
| RU2807294C1 (en) * | 2023-03-16 | 2023-11-13 | Федеральное государственное автономное образовательное учреждение высшего образования "Национальный исследовательский Томский политехнический университет" | Method of obtaining methyl lactate |
Also Published As
| Publication number | Publication date |
|---|---|
| EP2121561A1 (en) | 2009-11-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102256922B (en) | Carboxylicesters is prepared by alcohol vapor stripping | |
| US6916950B2 (en) | Process for preparing carboxylic esters | |
| CN102256923B (en) | Method for producing carboxylic acid esters | |
| CN102249913A (en) | Preparation method of butyl acrylate | |
| CN102803242A (en) | Process for preparing glycidyl esters of branched monocarboxylic acids | |
| CN102414166A (en) | Process for producing alpha-beta unsaturated carboxylic acid-N, N-disubstituted amide and process for producing 3-alkoxycarboxylic acid-N, N-disubstituted amide | |
| CN104640836A (en) | Method for preparing glycol ester using reactive distillation | |
| US5827939A (en) | Heteropolyacid catalysts in the preparation of esters of unsaturated carboxylic acids | |
| WO2008098581A1 (en) | A continuous process for the preparation of alkyl esters of lactic acid and aliphatic alcohols | |
| CA2501346C (en) | Process for the preparation of trimethylene terephthalate oligomers | |
| PL205694B1 (en) | Method of obtaining carboxylic esters | |
| CN100543001C (en) | 2, the preparation method of 5-norbornadiene | |
| US9156773B2 (en) | Alicyclic dicarboxylic acid ester compound and manufacturing method thereof | |
| CN104193598A (en) | Multi-reflux environment-friendly dimethoxymethane preparation process | |
| CN103724195A (en) | Synthetic method of ethylene glycol diacetate | |
| SG189954A1 (en) | Method for synthesizing beta-dicarbonyl compounds | |
| Vu et al. | Organocatalytic Cleavage of Fatty 1, 2-Diketones to Esters | |
| JP4656351B2 (en) | Process for producing ester by transesterification | |
| CN104193759A (en) | 4-hydroxymethyl-7-oxa bicyclo[2.2.1]hept-5-ene monomer and preparation method thereof | |
| JP6102548B2 (en) | Novel ethyladamantane dicarboxylic acid ester compound and method for producing the same | |
| HASSAN et al. | Synthesis of dimerate esters by solvent-free method | |
| CN110590555A (en) | Process for producing bis (2-hydroxyethyl) terephthalate | |
| CN109206314B (en) | Process for producing bis (2-hydroxyethyl) terephthalate | |
| CN112624905B (en) | Preparation method of novel tricyclodecanediol, product and application thereof | |
| RU2560156C1 (en) | Method of ethriol obtaining |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 07702546 Country of ref document: EP Kind code of ref document: A1 |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| WWE | Wipo information: entry into national phase |
Ref document number: 2007702546 Country of ref document: EP |