Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/20—Manufacture of shaped structures of ion-exchange resins
  • C08J5/22—Films, membranes or diaphragms
  • C08J5/2206—Films, membranes or diaphragms based on organic and/or inorganic macromolecular compounds
  • C08J5/2275—Heterogeneous membranes
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/02—Details
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
  • B01D71/06—Organic material
  • B01D71/52—Polyethers
  • B01D71/522—Aromatic polyethers
  • B01D71/5222—Polyetherketone, polyetheretherketone, or polyaryletherketone
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
  • B01D71/06—Organic material
  • B01D71/66—Polymers having sulfur in the main chain, with or without nitrogen, oxygen or carbon only
  • B01D71/68—Polysulfones; Polyethersulfones
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/10—Fuel cells with solid electrolytes
  • H01M8/1016—Fuel cells with solid electrolytes characterised by the electrolyte material
  • H01M8/1018—Polymeric electrolyte materials
  • H01M8/102—Polymeric electrolyte materials characterised by the chemical structure of the main chain of the ion-conducting polymer
  • H01M8/1023—Polymeric electrolyte materials characterised by the chemical structure of the main chain of the ion-conducting polymer having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/10—Fuel cells with solid electrolytes
  • H01M8/1016—Fuel cells with solid electrolytes characterised by the electrolyte material
  • H01M8/1018—Polymeric electrolyte materials
  • H01M8/102—Polymeric electrolyte materials characterised by the chemical structure of the main chain of the ion-conducting polymer
  • H01M8/1027—Polymeric electrolyte materials characterised by the chemical structure of the main chain of the ion-conducting polymer having carbon, oxygen and other atoms, e.g. sulfonated polyethersulfones [S-PES]
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/10—Fuel cells with solid electrolytes
  • H01M8/1016—Fuel cells with solid electrolytes characterised by the electrolyte material
  • H01M8/1018—Polymeric electrolyte materials
  • H01M8/102—Polymeric electrolyte materials characterised by the chemical structure of the main chain of the ion-conducting polymer
  • H01M8/1032—Polymeric electrolyte materials characterised by the chemical structure of the main chain of the ion-conducting polymer having sulfur, e.g. sulfonated-polyethersulfones [S-PES]
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/10—Fuel cells with solid electrolytes
  • H01M8/1016—Fuel cells with solid electrolytes characterised by the electrolyte material
  • H01M8/1018—Polymeric electrolyte materials
  • H01M8/1039—Polymeric electrolyte materials halogenated, e.g. sulfonated polyvinylidene fluorides
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/10—Fuel cells with solid electrolytes
  • H01M8/1016—Fuel cells with solid electrolytes characterised by the electrolyte material
  • H01M8/1018—Polymeric electrolyte materials
  • H01M8/1041—Polymer electrolyte composites, mixtures or blends
  • H01M8/1044—Mixtures of polymers, of which at least one is ionically conductive
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/10—Fuel cells with solid electrolytes
  • H01M8/1016—Fuel cells with solid electrolytes characterised by the electrolyte material
  • H01M8/1018—Polymeric electrolyte materials
  • H01M8/1041—Polymer electrolyte composites, mixtures or blends
  • H01M8/1053—Polymer electrolyte composites, mixtures or blends consisting of layers of polymers with at least one layer being ionically conductive
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2381/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing sulfur with or without nitrogen, oxygen, or carbon only; Polysulfones; Derivatives of such polymers
  • C08J2381/02—Polythioethers; Polythioether-ethers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2427/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers
  • C08J2427/02—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment
  • C08J2427/12—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
  • C08J2427/16—Homopolymers or copolymers of vinylidene fluoride
• • 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
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/30—Hydrogen technology
  • Y02E60/50—Fuel cells

Definitions

• the present invention relates to new blend polymer membranes based on sulfonated aromatic aryl polymers and their use as a polymer electrolyte membrane in fuel cells, in particular in low-temperature fuel cells.
• Fuel cell technology has great application potential in areas
• a polymer electrolyte membrane fuel cell contains cell units consisting of current collectors, gas distributors, electrodes and
• the electrodes usually contain platinum as a catalyst.
• Such fuel cells work with gaseous hydrogen or with methanol (DMFC Direct Methanol Fuel Cell).
• membranes With regard to use in fuel cells, membranes not only have to have sufficient chemical and mechanical stability and high proton conductivity, but also have to be inexpensive to produce. For this reason, inexpensive starting materials with excellent properties for functionalization and the inexpensive processes for membrane production are the decisive roles.
• PBI polybenzimidazole
• PES polyether sulfone
• phosphoric acid Wang, J.-T .; Savinell, R.F .; Litt, M .; Moaddel, H .; Rogers, C: Acid Doped Polybenzimidazoles, A New Polymer Electrolyte; The Electrochemical Society, Spring Meeting, San Francisco, May 22-27, Extended Abstracts, Vol. 94-1, 982-983 (1994)].
• Phosphoric acid molecules are attached to the polymer on the one hand through hydrogen bonds and on the other hand bound by protonation of the imidazole groups in the membrane. It is problematic, however, that the phosphoric acid is gradually eliminated from the PBI material with the water which is formed during the operation of the fuel cell. Furthermore, the PBI phosphoric acid membrane has a very low modulus of elasticity, which is why unsatisfactory membrane stability is to be expected in fuel cells.
• Blended polymer membranes based on sulfonated aryl polymers are known from DE-A-4422158, DE-A-198 13 613, DE-A-198 17 376 and DE-A-198 17 374, which have improved mechanical stability.
• An essential requirement for such blends is the compatibility of the selected materials. For this purpose, only those materials should be mixed whose chemical structure is similar and if specific interactions occur in polymers with mutually complementary groupings, for example the formation of polysalt from polyacid and polybase, hydrogen bonding, etc.
• the main advantage of the blend polymer membrane development is that the membrane structure and the membrane properties can be optimized by varying the blend component and the mixing ratio.
• DE-A-4422158 describes the blend polymer membranes made from sulfonated polyether ketone (PEK) and unmodified polyether sulfone (PES).
• PEK sulfonated polyether ketone
• PES unmodified polyether sulfone
• the two components are completely miscible with each other, which is due to their very similar chemical structures and the polarity of PES (lon-dipole interaction).
• this interaction which is caused by structural similarity, still appears to be inadequate, so that there is a risk that these membranes swell very strongly at an elevated temperature when the ion exchange capacity required for operation in fuel cells is used.
• DE-A-4422158 describes three or four component blends made from sulfonated PEK, PES, polyvinylpyrrolidone (PVP) and polyglycol dimethyl ether (PG), which show better water absorption without, however, giving any quantitative information.
• blends of sulfonated aryl polymer (PEEK and PSU) and polybenzimidazole PBI which have a covalent crosslinking through the proton transfer from sulfonated aryl polymer to PBI (eg PEEK-S0 2 -OHN-PBI).
• This crosslinking takes place at room temperature in the solvent, for example N-methylpyrrolidone (NMP), which forms an insoluble polyelectrolyte complex.
• NMP N-methylpyrrolidone
• the sulfonated aryl polymer must be in a soluble salt form being transformed. This additional step makes the manufacture of the membrane complex.
• Blended polymer membranes made from sulfonated aryl polymer PEEK or PSU with aminated polysulfone (PSU) are known from the prior art.
• Cui, W describes in the development and characterization of cation exchange membranes made of aryl polymers (VDI-Veriag; ISBN 3-18-359603-2) that the aminated polysulfones are a weak polybase and consequently a polyacid-base mixture can be prepared in the solution , Both the ionic interaction and the are between the blend components
• the object of the present invention is to provide an inexpensive polymer blend from which polymer electrolyte membranes for fuel cells can be produced, these having at least the same or an improved performance compared to the prior art.
• the property profile of these membranes should be able to be specifically adapted to the operating conditions in fuel cells by varying the mixing ratio.
• the above object is achieved by new blend polymer membranes crosslinked by ionic interaction based on modified polyether sulfone and polyether ether sulfone, for example aminated polyether sulfone as an enhancer and sulfonated aryl polymer as a functional polymer and a plasticizer.
• the present invention relates to a blend polymer membrane containing
• A) has at least one functional polymer based on one or more aryl polymers carrying sulfonic acid groups,
• the functional polymer used according to the invention is sulfonated aryl polymers, for example such as sulfonated PEEK (SPEEK), sulfonated PEK (SPEK), sulfonated PEEKK (SPEEKK), sulfonated PES (SPES) sulfonated PEES (SPEES).
• SPEEK sulfonated PEEK
• SPEK sulfonated PEK
• SPEEKK sulfonated PEEKK
• SPES sulfonated PES
• the blend polymer membrane can be made from PBI and modified polyether sulfone or modified polyether ether sulfone. Like PBI membrane, this blend polymer membrane is functionalized by phosphoric acid.
• Aryl polymers of this type contain aromatic building blocks selected from the group
• EP 0574791 describes the production of sulfonated PEEK.
• the production of sulfonated PEK is known from EP-A-008895, EP-A-041780 and EP 0576807.
• the production of sulfonated PEEKK is known from E. Müller in "Crosslinked PEEKK sulfonamides for the separation of aliphatic / aromatic mixtures" [diploma thesis, 1995, Hoechst AG, Frankfurt / Main].
• EP-A-0008894 and EP-A- 0112724 describes the production of polyether sulfone.
• the degree of sulfonation is preferably between 0.1 and 100%
• the functional polymer according to the invention is used in amounts between 30 and 99.9% by weight, based on the total polymer.
• the reinforcing polymer used according to the invention is aminated polyether sulfone and polyether ether sulfone containing the structural units
• x is independently an integer 0, 1, 2, 3 or 4,
• x is independently an integer 0, 1, 2, 3 or 4
• Aminated polyether sulfones and polyether ether sulfones containing structural units of the types are particularly preferred
• Nitrated polyether sulfones and polyether ether sulfones containing structural units of the types are particularly preferred
• the reinforcing polymer according to the invention is used in amounts between 0.1 and 70% by weight, preferably 10 to 50% by weight, based on the total polymer.
• polyacid-polybase blends or polyacid-polyacid blends can be represented as follows:
• the sulfonated polyether sulfone (PES-S03H) and the nitrided PES (PES-N02) are both polyacid and therefore completely miscible with each other.
• the compatibility between PES-S03H and aminated PES (PES-NH 2 ) is harmless due to the complete miscibility of the polyacid-polybase mixture.
• PES-NH and PES-NO 2 serve as "macromolecular counterions" to reinforce the membrane. Although the ionic compound is dissolved in water at elevated temperature, the interaction is retained due to the location of the "macromolecular counterions" at the sites.
• the membrane is reinforced at elevated temperature by these “macromolecular counterions” and, on the other hand, the ion transport is promoted because of this dissolution.
• the membrane according to the invention thus has the favorable properties for use in fuel cells at elevated temperature.
• Polyethersulfones (PES ) are commercially available and are characterized by high thermal, chemical resistance and mechanical stability
• plasticizers are understood to be those which reduce the brittleness of the membrane produced from the polymer blend. Suitable plasticizers must be inert under the conditions prevailing in a fuel cell. Furthermore, the plasticizers must be miscible and compatible with the functional and reinforcing polymer and must be soluble in the same dipolar solvent, for example dimethylformamide (DMF), dimethyl oxide (DMSO), N-methylpyrrolidone (NMP) or N, N-dimethylacetamide (DMAC) his.
• a linear polyvinylidene fluoride (PVDF) is particularly preferably used as the plasticizer.
• the three-component blend polymer membrane made of functional polymer, reinforcer and plasticizer is miscible due to the hydrogen bond, acid-base interaction and ion-dipole interaction.
• a physical cross-linking in the membrane also contributes to this.
• the ion-dipole interaction between PVDF and modified aryl polymers is very weak. If the mixing part of PVDF is increased, a phase separation is created in the membrane. This makes the membrane optically cloudy.
• the plasticizer content is up to 5% by weight, preferably between 0.001 and
• PVDF is commercially available and is characterized by excellent chemical and thermal stability.
• the chemical structure of PVDF can be described as follows
• the three-component blend polymer membrane according to the invention is also produced by the process below.
• the blend polymer membranes according to the invention are produced as follows: a solution of a homogeneous polymer mixture containing the sulfonated aryl polymer, the aminated PES or the nitrated PES and plasticizer is poured onto a support and then a uniformly thick film is drawn out with a doctor blade.
• the solvent in the film is e.g. by
• the membrane structure or the membrane properties such as conductivity, membrane swelling can be adjusted depending on the intended use, the blend polymer membranes according to the invention having improved mechanical and thermal properties compared to the membranes made from sulfonated aryl polymer.
• the blend polymer membrane according to the invention can consist of one layer or of several identical or different layers (multilayer), for. B. from double layer of a) sulfonated aryl polymer and aminated polysulfone and b) sulfonated aryl polymer and nitrided polysulfone.
• Multi-layer membranes according to the invention, the at least two different layers selected from the group SPEK and NH 2 -PES, SPEK and N0 2 -PES, SPEK and NH 2 -PES and plasticizers, SPEK and N0 2 -PES and plasticizers.
• Ion exchange capacity (IEC, meq / g): The potentiometric titration was used to determine the ion exchange capacity of the membrane.
• Measuring cell based on the temperature from 20 ° C to 90 ° C using the
• the sample was pretreated for 4 hours in a climatic oven at 23 ° C. and 50% humidity, or the sample was
• Membranes were determined using DSC and TGA (Mettler Toledo; 10 k / min).
• Methanol permeability (32g methanol in 1000g H 2 O) was determined depending on the temperature at Fr. S. Pauly / A. Becker in Wiesbaden with the help of
• the permeability of the comparison membrane is as follows:
• the SPEEK has an ion exchange capacity of 1.73 meq / g.
• the NH 2 -PES has a degree of substitution of 45% (1.9 meq / g).
• the blend polymer membrane TE-4 consists of 90% by weight SPEEK and 10% by weight NH 2 -PES, TE-5 from 85
• the material permeability in the membrane TE-5 is 2.35 [g.50 ⁇ m / (m 2 .d)] at 40 ° C.
• FIG. 1 The permeability to hydrogen and oxygen as a function of temperature (TE-5) is shown by FIG. 1:
• SPEEKK has an ion exchange capacity of 1.65 meq / g.
• the NH -PES is the degree of substitution of 45% (1.9 meq / g).
• the blend polymer membrane TE-8 consists of 90% by weight SPEEKK and 10% by weight NH 2 -PES, TE-9 consists of 85% by weight SPEEKK and 15% by weight NH 2 -PES.
• the methanol permeability in the membrane TE-8 is 4.11 [g.50 ⁇ m / (m 2 .d)] at 40 ° C.
• the SPEK has an ion exchange capacity of 2.13 meq / g.
• the NO 2 -PES is the degree of substitution of 50% (1, 97meq / g).
• the SPEK has an ion exchange capacity of 2.13 meq / g.
• the NH 2 -PES has a degree of substitution of 45% (1.9 meq / g).
• the blend polymer membrane TE-1 consists of 85% by weight SPEK and 15% by weight NH 2 -PES, TE-2 80
• IEC 1.82 meq / g
• Three-component blend polymer membranes made of SPEK, NH 2 -PES (IEC 1, 9 meq / g) and PVDF.
• the measuring device is a dynamic mechanical analyzer DMA 242 (from Netzsch-
• the foils shrink with increasing temperature.
• the sample expands due to the further rise in temperature.
• the module drops sharply from 200 ° C.
• the sample expands enormously and the tan ⁇ curve experiences a maximum.
• the maximum results in a glass transition temperature of 254 ° C for TE-31 and TE-28. The results are shown in the tab.
• the membranes TE-31 and sulfonated, perfluorinated polymer, for example Nafion-115, are characterized by a high damping behavior.
• the glass transition temperature was determined using DSC, and the
• Decomposition temperature was determined using TGA.
• Electrode 0.16 mg / cm 2 ;
• Cathode 0.62 mg / cm 2 ;
• Electrode 0.16 mg / cm 2 ;
• Cathode 0.62 mg / cm 2 ;
• hydrogen is introduced into the anode cells and oxygen into the cathode cells. There may be a reduction in membrane material
• Such a membrane with the double layer consisting of a total of four components.
• One of the double layers consists of sulfonated PEK, aminated PES and PVDF, the other of sulfonated PEK, nitrided PES and PVDF.
• PES-NO 2 is very stable against oxidation under oxygen
• PES-NH 2 is very stable against reduction under hydrogen or methanol.
• the production of the multilayer membrane is carried out according to the following steps: • First, a membrane layer according to that described in section 1
• PVDF 1 wt% lower side: SPEK (2.13 meq / g): 75 wt%; NO 2 -PES (1.97 meq / g): 24% by weight;
• PVDF 1% by weight

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• 2000
  • 2000-03-02 DE DE10010001A patent/DE10010001A1/de not_active Withdrawn
• 2001
  • 2001-03-01 CN CNB018058868A patent/CN1227056C/zh not_active Expired - Fee Related
  • 2001-03-01 MX MXPA02008584A patent/MXPA02008584A/es not_active Application Discontinuation
  • 2001-03-01 CA CA002401838A patent/CA2401838C/en not_active Expired - Fee Related
  • 2001-03-01 JP JP2001563213A patent/JP2003526716A/ja not_active Withdrawn
  • 2001-03-01 AT AT01911711T patent/ATE270141T1/de not_active IP Right Cessation
  • 2001-03-01 DE DE50102740T patent/DE50102740D1/de not_active Expired - Lifetime
  • 2001-03-01 ES ES01911711T patent/ES2228818T3/es not_active Expired - Lifetime
  • 2001-03-01 WO PCT/EP2001/002311 patent/WO2001064322A1/de not_active Ceased
  • 2001-03-01 KR KR1020027011424A patent/KR100734800B1/ko not_active Expired - Fee Related
  • 2001-03-01 EP EP01911711A patent/EP1268045B1/de not_active Expired - Lifetime
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