Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/40—Regeneration or reactivation
  • B01J31/4015—Regeneration or reactivation of catalysts containing metals
  • B01J31/4023—Regeneration or reactivation of catalysts containing metals containing iron group metals, noble metals or copper
  • B01J31/4038—Regeneration or reactivation of catalysts containing metals containing iron group metals, noble metals or copper containing noble metals
  • B01J31/4046—Regeneration or reactivation of catalysts containing metals containing iron group metals, noble metals or copper containing noble metals containing rhodium
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
  • B01J31/22—Organic complexes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
  • B01J31/22—Organic complexes
  • B01J31/2204—Organic complexes the ligands containing oxygen or sulfur as complexing atoms
  • B01J31/2208—Oxygen, e.g. acetylacetonates
  • B01J31/2213—At least two complexing oxygen atoms present in an at least bidentate or bridging ligand
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
  • C07C45/49—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reaction with carbon monoxide
  • C07C45/50—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reaction with carbon monoxide by oxo-reactions
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
  • B01J2231/30—Addition reactions at carbon centres, i.e. to either C-C or C-X multiple bonds
  • B01J2231/32—Addition reactions to C=C or C-C triple bonds
  • B01J2231/321—Hydroformylation, metalformylation, carbonylation or hydroaminomethylation
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2531/00—Additional information regarding catalytic systems classified in B01J31/00
  • B01J2531/02—Compositional aspects of complexes used, e.g. polynuclearity
  • B01J2531/0261—Complexes comprising ligands with non-tetrahedral chirality
  • B01J2531/0266—Axially chiral or atropisomeric ligands, e.g. bulky biaryls such as donor-substituted binaphthalenes, e.g. "BINAP" or "BINOL"
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2531/00—Additional information regarding catalytic systems classified in B01J31/00
  • B01J2531/80—Complexes comprising metals of Group VIII as the central metal
  • B01J2531/82—Metals of the platinum group
  • B01J2531/822—Rhodium
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
  • B01J31/22—Organic complexes
  • B01J31/2282—Unsaturated compounds used as ligands
  • B01J31/2295—Cyclic compounds, e.g. cyclopentadienyls
• • 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 new catalyst and a process for the preparation of aldehydes by reacting olefinic compounds with carbon monoxide and hydrogen in the presence of this catalyst.
• aldehydes Due to their chemical properties, aldehydes represent an important group of organic compounds. They can be converted, for example by aldol reaction with themselves or another C-H acid compound (methylene component), into the corresponding aldols or, after dehydration of the aldol, into the corresponding unsaturated condensation products. Furthermore, aldehydes can be oxidized to the corresponding carboxylic acids or reduced to the corresponding alcohols. By reacting aldehydes with ammonia or amines, imines or Schiff's bases are accessible, which give the corresponding amines by reaction with hydrogen.
• C-H acid compound methylene component
• Aldehydes are obtained on an industrial scale by the hydroformylation of olefinic compounds. As a result of the reaction of the carbon-carbon double bonds with carbon monoxide and hydrogen, mixtures of straight-chain and branched aldehydes are formed, as the following reaction equation shows schematically using a terminal olefin.
• CH CH 2 ⁇ R CH CH 3 + R CH 2 CH 2 CHO
• rhodium catalysts which contain phosphorus-containing ligands have proven particularly useful as hydroformylation catalysts.
• Suitable ligands containing phosphorus are phosphines or phosphites. Such a hydroformylation process is described in DE-PS 1 7 93 069.
• the phosphites and in particular the phosphines are not stable to oxygen and sulfur and are oxidized even by very small amounts of oxygen and / or sulfur.
• the oxygen mainly enters the reaction via the olefin used as the starting material, while the sulfur is fed to the reaction in the form of sulfur-containing compounds, for example as H 2 S, via the synthesis gas.
• phosphinic acids, thiophosphates, phosphine oxides and phosphine sulfides no longer function as a complexing ligand and are therefore no longer catalytically active. Sulfur-containing compounds also frequently impair catalytic processes and act as catalyst poisons.
• the phosphates, thiophosphates, phosphine oxides and phosphine sulfides formed are undesirable in the hydroformylation and must therefore be separated off. Separating them, like working up the catalyst or rhodium, proves to be difficult and requires a high level of technical effort.
• the phosphites are somewhat less sensitive to oxygen and / or sulfur than the phosphines. In contrast to these, however, they are sensitive to water and hydrolyze even under the influence of small to very small amounts of moisture. Small amounts of water reach the reaction via the olefin used and the synthesis gas. By recycling the catalyst containing the phosphites, they come together again and again with the water originating from the olefin and synthesis gas, with the result that the hydrolysis proceeds and more and more phosphite is hydrolytically split. The hydrolysis products of the phosphites no longer have a complexing effect and are also no longer catalytically active.
• the catalyst should also have sufficient hydroformylation activity and, after use, should also be able to be used again in the hydroformylation step without any appreciable loss of hydroformylation activity. Furthermore, the catalyst should also withstand thermal stress, which does not take place under the conditions of the hydroformylation, without being damaged.
• the resulting hydroformylation mixture is initially expanded in two stages, with excess synthesis gas being separated off and fed back to the hydroformylation, optionally after recompression.
• the reaction product freed from the synthesis gas goes into a multi-stage distillation in which the product of value is separated from the distillation residue containing higher boilers and subsequently fractionally distilled.
• the hydroformylation catalyst remains in the distillation residue.
• the hydroformylation catalyst can be deactivated, for example by decomposition or deposition of colloidal metal. However, such a deactivated catalyst is no longer suitable for reuse.
• a catalyst it is necessary for a catalyst to withstand the conditions of distillation without any significant loss of hydroformylation activity and also hydroformylation selectivity and, for example, as a distillation residue containing a catalyst, to be successfully used again in the hydroformylation stage.
• the catalyst should be able to be produced without great technical outlay and comparatively readily accessible starting materials should be used in its production.
• R 1 , R 2 and R 3 are the same or different and independently of one another represent hydrogen, an alkyl or alkoxy group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms or R 1 and R 2 , including those each connected to them Carbon atoms form a ring with 6 carbon atoms, m and n independently of one another are 0 or 1 and (m + n) are 1 or 2, and R for an unsubstituted or through an alkyl group with 1 to 4 carbon atoms, an amino or dialkylamino group with a total of 2 to 8 carbon atoms substituted phenyl or naphthyl radical.
• the compounds of the formula (I) are bisether containing 2,2'-bisaryl. These compounds and their preparation are the subject of a German patent application filed on the same day as the present patent application (file number 1 9 625 1 67.2).
• the bisethers containing the 2,2'-bisaryl radical are resistant to both oxygen and sulfur. Furthermore, they are also subject to the conditions of Hydroformylation not hydrolyzable. They also transfer these advantageous properties to the catalyst according to the invention containing rhodium and a compound of the formula (I).
• the catalyst according to the invention has a hydroformylation activity and hydroformylation selectivity comparable to pure rhodium, since ligand-containing rhodium catalysts usually have a significantly reduced hydroformylation activity and changed hydroformylation selectivity compared to pure rhodium.
• the hydroformylation selectivity is expressed, inter alia, in the ratio in which n-aldehydes and i-aldehydes are formed and the extent to which isomerization of the olefinic compounds takes place, for example with migration of the carbon-carbon double bond.
• the comparatively high thermal load capacity of the rhodium complex catalysts described, for example, in DE-PS 1 7 93 063 is due to the pronounced ability of the phosphites and phosphines used to form stable complexes with rhodium.
• the trivalent phosphorus acts as a coordination partner towards rhodium.
• the catalyst according to the invention also has a high thermal stability, although the compound of the formula (I) does not contain trivalent phosphorus.
• the extraordinarily high thermal load capacity is demonstrated by the fact that the reaction mixture obtained in the hydroformylation can be distilled off and the catalyst remaining in the distillation residue is not decomposed or deactivated, but can instead be used again in the hydroformylation reaction.
• the catalyst according to the invention has a significant increase in stability, as can be seen from the comparative examples carried out using unmodified pure rhodium (rhodium without ligand) as the hydroformylation catalyst.
• the catalyst contains rhodium and in particular a compound of the formula (I), in which R 1 , R 2 and R 3 are identical or different and independently of one another represent hydrogen, an alkyl or alkoxy group having 1 to 2 carbon atoms or R 1 and R 2 form a ring with 6 carbon atoms including the carbon atoms connected to them.
• R 1 , R 2 and R 3 are identical or different and independently of one another represent hydrogen, an alkyl or alkoxy group having 1 to 2 carbon atoms or R 1 and R 2 form a ring with 6 carbon atoms including the carbon atoms connected to them.
• R usually represents an unsubstituted or a phenyl or naphthyl radical substituted by an alkyl group having 1 to 4 carbon atoms, in particular an unsubstituted or substituted phenyl radical or an alkyl group having 1 to 4 carbon atoms, preferably a phenyl radical .
• R 1 and R 2 each form a ring, including the carbon atoms of the respective benzene ring connected to them, giving a 1, 1-binaphthyl substituted in the 2,2'-position, while in formula (III ) R 1 and R 2 represent hydrogen.
• R 3 is both in formula (II) and in formula (III) hydrogen.
• the catalyst can be prepared in a simple manner by combining rhodium, for example in the form of a salt, with the compound of the formula (I). It is particularly favorable to use the rhodium in the form of a salt which is soluble in an organic solvent, for example as the rhodium salt of an aliphatic carboxylic acid having 2 to 10 carbon atoms, for example as rhodium acetate, rhodium butyrate, rhodium 2-ethylhexanoate or rhodium acetylacetonate, and together with the compound of the formula (I) dissolve in an organic solvent. You can also first dissolve the rhodium salt and then add the compound of formula (I) or, conversely, first dissolve the compound of formula (I) and then add the rhodium salt.
• a salt which is soluble in an organic solvent for example as the rhodium salt of an aliphatic carboxylic acid having 2 to 10 carbon atoms, for
• the solvent used here should be inert under the conditions of the hydroformylation.
• examples of such a solvent are toluene, o-xylene, m-xylene, p-xylene, mixtures of isomeric xylenes, ethylbenzene, mesitylene or species-specific reaction products which are recirculated with the catalyst.
• reaction product formed in the hydroformylation is also possible to use the reaction product formed in the hydroformylation as a solvent.
• the catalyst containing rhodium and the compound of formula (I) can be used directly in the hydroformylation, that is to say without additional treatment.
• the catalyst containing rhodium and the compound of the formula (I) it is also possible to first subject the catalyst containing rhodium and the compound of the formula (I) to a pretreatment in the presence of hydrogen and carbon monoxide under pressure and, if appropriate, elevated temperature, and to prepare the actually active catalyst species by means of this preforming.
• the conditions for the preforming usually correspond to the conditions of a hydroformylation.
• the catalyst usually contains rhodium and the compound of formula (I) in a molar ratio of 1: 1 to 1: 1000, in particular 1: 1 to 1:50, preferably 1: 2 to 1:20.
• the catalyst can contain rhodium and the compound of the formula (I) in a molar ratio of 1: 1,000 to 1: 5000, in particular 1: 1,000 to 1: 2000.
• the present invention further relates to a method for producing aldehydes. It is characterized in that an olefinic compound having 2 to 20 carbon atoms in the presence of a rhodium and a compound of the general formula (I)
• R 1 , R 2, R 3 , m, n and R have the meaning explained above, containing catalyst with carbon monoxide and hydrogen at a pressure of 1 0 to 500 bar and a temperature of 90 to 1 50 ° C.
• the reaction can be carried out in the presence or absence of a solvent which is inert under the conditions of the hydroformylation.
• Suitable solvents are, for example, toluene, o-xylene, m-xylene, p-xylene, mixtures of isomeric xylenes, ethylbenzene, mesitylene or species-specific reaction products which are recirculated with the catalyst. Mixtures of these solvents can also be used.
• the reaction product formed in the hydroformylation is usually also suitable as the solvent.
• the olefinic compound can contain one or more than one carbon-carbon double bond.
• the carbon-carbon double bond can be arranged terminally or internally.
• Examples of ⁇ -olefinic compounds are alkenes, alkylalkenoates, alkenylalkanoates, alkenylalkyl ethers and alkenols, in particular those having 2 to 8 carbon atoms.
• the ⁇ -olefinic compounds are propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1 -decene, 1 -dodecene, 1 -octadecene, 2-ethyl-1 - hexene, styrene, 3-phenyl-1-propene, allyl chloride, 1, 4-hexadiene, 1, 7-octadiene, 3-cyclohexyl-1-butene, allyl alcohol, hex-1-en-4-ol, oct-1 - en-4-ol, vinyl acetate, allyiacetate, 3-butenyl acetate, vinyl propionate, allyl propionate, allyl butyrate, methyl methacrylate, vinyl cyclohexene, 3-butenyl acetate, vinyl ethyl ether, vinyl methyl ether
• olefinic compounds examples include butene-2, diisobutylene, tripropylene, octol or dimersol (dimerization products of butenes), tetrapropylene, cyclohexene, cyclopentene, dicyclopentadiene, acyclic, cyclic or bicyclic terpenes, such as myrcene, limonene and pinene.
• Containing catalyst (I) requires the rhodium and described above, the compound of the formula usually used in an amount of from 2x1 0 "6 to 5x 1 0 '2, in particular 5x1 0" 6 to 5x10 "3, preferably 1 x1 0" 5-1 x10 "4 moles of rhodium per mole of olefinic compound.
• the amount of rhodium also depends on the type of olefinic compound to be hydroformylated. In some cases, it may suffice to use the catalyst in an amount of 1 x 10 ⁇ 6 moles of rhodium per mole of olefinic compound or less. Although such low catalyst concentrations are possible, they may not prove to be particularly useful in individual cases, since the reaction rate may be too slow and therefore not economical enough.
• the upper catalyst concentration can be up to 1 x10 ⁇ 1 mol of rhodium per mol of olefinic compound. Comparatively high rhodium concentrations, however, do not result in any special advantages. Therefore the upper limit is set by the high cost of rhodium.
• the reaction is carried out in the presence of hydrogen and carbon monoxide.
• the molar ratio of hydrogen to carbon monoxide can be chosen within wide limits and is usually 1: 10 to 1 0: 1, in particular 5: 1 to 1: 5, preferably 2: 1 to 1: 2.
• the process is particularly simple if hydrogen and carbon monoxide are used in a molar ratio of 1: 1 or approximately 1: 1.
• reaction conditions in particular rhodium concentration, pressure and temperature, also depend on the type of olefinic compound to be hydroformylated.
• Comparatively reactive olefinic compounds require low rhodium concentrations, low pressures and low temperatures.
• relatively unreactive olefinic compounds requires higher rhodium concentrations, higher pressures and higher temperatures.
• the process can be carried out with particularly good success if a cc -olefinic compound is used.
• a cc -olefinic compound is used.
• other olefinic compounds with internal carbon-carbon double bonds can also be implemented with good results.
• the hydroformylation mixture is freed of carbon monoxide and hydrogen and then distilled, the aldehyde-containing product of value usually being distilled off overhead.
• the catalyst containing rhodium and the compound of formula (I) remains in the distillation residue and can be used again in this form in the hydroformylation reaction.
• reaction product obtained after reaction with carbon monoxide and hydrogen is freed from the low-boiling constituents in a first distillation stage and from high-boiling thick oils in a second distillation stage under more stringent distillation conditions, and the bottom product containing the catalyst, which is obtained in the second distillation stage, is passed into the reaction of the olefinic compound back with carbon monoxide and hydrogen.
• the process according to the invention can be carried out continuously or batchwise, in particular continuously.
• the catalyst is made from 0.073 mmol rhodium and 0.73 mmol 2,2'-bis (phenoxymethyU-1, 1'-binaphthyl as ligand, corresponding to a molar ratio Rh: ligand of 1: 10 - as follows in the hydroformylation of propylene described in Example 1 - produced in situ.
• the reaction temperature is controlled by cooling the autoclave by means of a blower and by the rate at which the propylene is pumped in.
• the autoclave is then cooled to room temperature and a
• the hydroformylation product is transferred in one under N 2 protection
• the total duration of the distillation is 2.5 hours. 1 6
• the residue containing the catalyst is taken up in each case with so much butyral distillate that the total amount is about 400 g and thus gives the same level in the autoclave (volume: 5 liters), and is transferred back into the autoclave with N 2 pressure.
• About 400 g of product catalogid-containing residue + butyraldehyde distillate
• the implementation is exothermic.
• the reaction temperature is controlled by cooling the autoclave by means of a blower and by the rate at which the propylene is pumped in. After pumping in, the reaction is allowed to continue.
• the total reaction time (pumping time + post-reaction time) can be found in the table below under the heading Time. 1 7
• the autoclave is then cooled to room temperature and expanded to 2 to 5 bar via a cold trap. There is always a small amount of product in the cold trap. With the residual pressure, the contents of the autoclave are transferred to a 6 l glass flask via a dip tube and weighed.
• the propylene conversion shown in the table below is calculated from the increase in weight of the combined liquid products (see sales category).
• the ratio of n-butanal: i-butanal, determined by gas chromatography, is 52:48 in each case.
• the hydroformylation product obtained in Examples 2 to 7 is transferred to a rotary evaporator and the aldehydes (n-butanal and i-butanal) are first distilled at 80 ° C. and towards the end at 100 ° C. and a water jet vacuum, which is initially 100 mbar and towards the end the distillation is from 25 mbar.
• Example 2 gives 1,51 g of residue and is used in Example 3 (2nd reuse)
• the hydroformylation product obtained in Example 3 gives 253 g of residue and is used in Example 4 (3rd reuse)
• Example 4 Hydroformylation product 351 g of residue and is used in Example 5 (4th reuse) as a catalyst (rhodium and ligand).
• Example 6 Thereafter, a conversion of 94% is achieved in Example 6 (5th reuse). The
• Thick oils obviously have a deactivating effect on the catalyst.
• Comparative Example 4 (3rd reuse) shows that no propylene is reacted at all.
• the hydroformylation product obtained in Comparative Examples 2 and 3 is transferred to a rotary evaporator and the aldehydes (n-butanal and i-butanal) are distilled off as described in Examples 2 to 8 under b) recovery of the catalyst.
• the hydroformylation product obtained in comparative example 2 gives 293 g of rhodium-containing residue, which is used in comparative example 3 (second reuse), and the hydroformylation product obtained in comparative example 3 gives 273 g of rhodium-containing residue, which is used in comparative example 4 (third reuse) .
• the results of Examples 1 to 8 and Comparative Examples 1 to 4 are summarized in the table below.

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• 1996
  • 1996-06-24 DE DE19625168A patent/DE19625168A1/de not_active Withdrawn
  • 1996-06-24 DE DE19654908A patent/DE19654908A1/de not_active Withdrawn
• 1997
  • 1997-06-18 PL PL97330789A patent/PL330789A1/xx unknown
  • 1997-06-18 KR KR1019980710533A patent/KR20000022119A/ko not_active Application Discontinuation
  • 1997-06-18 BR BR9709955A patent/BR9709955A/pt not_active Application Discontinuation
  • 1997-06-18 EP EP97929208A patent/EP0909218A1/de not_active Withdrawn
  • 1997-06-18 CA CA002258280A patent/CA2258280A1/en not_active Abandoned
  • 1997-06-18 WO PCT/EP1997/003169 patent/WO1997049490A1/de not_active Application Discontinuation
  • 1997-06-18 AU AU33401/97A patent/AU3340197A/en not_active Abandoned
  • 1997-06-18 JP JP10502267A patent/JP2001502594A/ja active Pending
  • 1997-06-20 TW TW086108670A patent/TW372199B/zh active
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