Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
  • C11D1/66—Non-ionic compounds
  • C11D1/83—Mixtures of non-ionic with anionic compounds
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/16—Organic compounds
  • C11D3/37—Polymers
  • C11D3/3746—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
  • C11D3/3757—(Co)polymerised carboxylic acids, -anhydrides, -esters in solid and liquid compositions
  • C11D3/3765—(Co)polymerised carboxylic acids, -anhydrides, -esters in solid and liquid compositions in liquid compositions

Definitions

• EP-PS 0 116 930 describes water-soluble copolymers of 40 to 90% by weight of at least one ethylenically unsaturated monocarboxylic acid with 3 to 5 C atoms and 60 to 10% by weight of at least one ethylenically unsaturated dicarboxylic acid with 4 to 8 C atoms and / or their corresponding dicarboxylic acid anhydrides are known, in which 2 to 60% by weight, based on the total weight of the carboxylic acids or carboxylic acid anhydrides, are esterified with alkoxylated C1 to C18 alcohols or C1 to C12 alkylphenols.
• the partially esterified copolymers and their water-soluble salts are used, inter alia, in amounts of 0.5 to 10% by weight also used in liquid detergent formulations.
• the compatibility of the partially esterified copolymers of at least one monoethylenically unsaturated monocarboxylic acid and at least one monoethylenically unsaturated dicarboxylic acid is significantly more favorable than that of the non-esterified products, so that there are fewer phase separations.
• the partially esterified copolymers of the type described are not stable to hydrolysis, so that they hydrolyze in liquid detergent formulations. As a result, inhomogeneities occur, which can even go so far as to result in phase separation of the liquid detergent.
• liquid detergents which contain at least one nonionic surface-active agent in an amount of 5 to 25% by weight, 2 to 25% by weight of a builder, approximately 1 to 10% by weight of C4- to C30 - contain ⁇ -olefin-maleic anhydride copolymers and, to make up to 100% by weight, water. Although these liquid detergents initially represent clear solutions, they separate relatively quickly during storage.
• liquid alkaline detergent formulations which, in addition to water and detergents as stabilizers, contain 0.1 to 5%, based on the entire formulation, of a hydrolyzed copolymer of an ⁇ , ⁇ -unsaturated carboxylic anhydride with a vinyl ester, vinyl ether or contain an ⁇ -olefin in partially esterified form.
• Addition products of alkylene oxides, in particular ethylene oxide, onto alkylphenols are also suitable as alcohol components for the esterification. Only 0.01 to 5% of the carboxyl groups of the copolymer are present as ester groups.
• these liquid detergents contain components which are compatible with one another, ie they remain in solution without separating or clouding, the primary washing action of this liquid detergent formulation is still in need of improvement.
• the present invention has for its object to provide polymers for the preparation of stable liquid detergent formulations which have an improved primary and secondary washing action compared to the liquid detergent formulations of the prior art.
• stable liquid detergent formulation should be understood to mean the fact that the individual components of the formulation are compatible with one another and do not separate even after prolonged storage.
• liquid detergents which contain the partially esterified copolymers to be used according to the invention, when mixed with aqueous alkaline solutions of anionic and / or nonionic surfactants, give clear aqueous solutions which are stable on storage. These formulations have an increased primary and secondary washing action compared to comparable liquid detergents of the prior art.
• the isomeric trimethylpentenes mentioned can be used in any ratio in the copolymerization.
• Mixtures of these olefins which are used with particular preference comprise 35 to 45 mol% of 2,4,4'-trimethylpentene-1 and 5 to 15 mol% of 2,4,4'-trimethylpentene-2.
• Terpolymers which contain trimethylpentenes in copolymerized form with maleic anhydride are known, for example, from EP-PS 9 169 and EP-PS 9 170.
• Said olefins having 4 to 28 carbon atoms can optionally also be mixed with C1 to C28 alkyl vinyl ethers, e.g.
• Methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether or isobutyl vinyl ether can be copolymerized.
• the proportion of alkyl vinyl ethers in the mixture with at least one of the olefins in question is up to 20 mol%.
• mixtures of 80 mol% diisobutylene and 20 mol% methyl vinyl ether can be used as component (a).
• Monoethylenically unsaturated dicarboxylic anhydrides having 4 to 8 carbon atoms for example maleic anhydride, itaconic anhydride, mesaconic anhydride, citraconic anhydride and methylene malonic anhydride, are suitable as component (b) for the preparation of the copolymers.
• maleic anhydride and itaconic anhydride are preferably used, maleic anhydride being of particular importance in practice.
• the copolymerization of the monomers according to (a) and (b) produces alternating copolymers which contain the monomers mentioned in copolymerized form in a molar ratio of 1: 1.
• the K values of the copolymers are 6 to 100, preferably 8 to 40 (measured according to H. Fikentscher at 25 ° C. in tetrahydrofuran and a polymer concentration of 1% by weight).
• the copolymerization of the monomers (a) and (b) is carried out by known processes, for example in polar solvents which are inert to the acid anhydrides, such as acetone, tetrahydrofuran or dioxane as solution polymerization, in toluene, xylene or aliphatic hydrocarbons in the form of a precipitation polymerization or else by Bulk polymerization of components (a) and (b), it being advantageous to choose an excess of monomers of component (a) as the diluent.
• the polymerization is initiated in all processes with the aid of polymerization initiators. All compounds which break down into free radicals, for example peroxides, hydroperoxides, redox initiators and azo compounds, are suitable as polymerization initiators.
• the copolymers thus obtainable are then partially esterified and hydrolyzed, so that the anhydride groups are converted into carboxyl groups. It is also possible to first hydrolyze the copolymers containing anhydride groups so that all anhydride groups are present as carboxyl groups and then to carry out the esterification by known methods. However, a procedure is preferred in which the carboxylic anhydride groups of the copolymer are first partially esterified with the reaction products of (A) and (B).
• Suitable compounds (A) are C1 to C30 alcohols, e.g. Methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, pentanol, cyclohexanol, n-hexanol, n-octanol, 2-ethylhexanol, decanol, dodecanol and stearyl alcohol.
• the alcohols produced by the oxo process e.g. C10 alcohols, C13 alcohols and C13 / C15 alcohols or also natural alcohols, such as e.g. C16 / C18 tallow fatty alcohols.
• These alcohols and the native alcohols produced by the oxo process are generally mixtures of several alcohols.
• Suitable compounds (A) are also C8 to C22 fatty acids, e.g. Stearic acid, palmitic acid, coconut fatty acid, tallow fatty acid, lauric acid and behenic acid.
• Component (A) also includes C1 to C12 alkylphenols, e.g. n-decylphenol, n-nonylphenol, isononylphenol, n-octylphenol, isobutylphenol and methylphenol.
• Secondary C2 to C30 amines are also used as component (A), e.g. Dimethylamine, di-n-butylamine, di-n-octylamine and di-stearylamine.
• Secondary C8 to C18 fatty amines are preferably used.
• C1 to C3 C alcohols or sec.-C2 to C1 sek amines are preferably used as component (A).
• component (B) are C2 to C4 alkylene oxides, such as ethylene oxide, propylene oxide, n-butylene oxide and isobutylene oxide. Also comes Tetrahydrofuran as component (B) into consideration.
• Compounds (B) which are preferably used are ethylene oxide and propylene oxide.
• Ethylene oxide and propylene oxide can either be added alone to the compounds indicated under (A) or in the form of a mixed gas with the formation of adducts containing random ethylene oxide and propylene oxide units, or else in such a way that ethylene oxide is initially added to the compounds mentioned under (A) and then adds propylene oxide or reverses the order, or first adds ethylene oxide, then propylene oxide and again ethylene oxide to the compounds (A), so that block copolymers are formed.
• Methods for the alkoxylation of the compounds (A) belong to the prior art.
• the compounds (A) are reacted with the compounds (B) in a molar ratio of (A) to (B) from 1: 2 to 50, preferably 1: 3 to 12. This reaction produces reaction products in all cases in which at least one end group is an OH group.
• the reaction products of (A) and (B) thus produced are reacted with the copolymers of monomers (a) and (b) described above, partially esterified copolymers being formed.
• This reaction can be carried out in the presence of solvents which are inert to carboxylic anhydride groups, for example acetone or tetrahydrofuran, and is preferably carried out in bulk, ie the copolymers containing olefin-dicarboxylic anhydride groups are reacted directly with the reaction products of (A) and (B).
• the amounts are chosen so that only partial esterification of the anhydride groups occurs.
• Based on the hydrolyzed partially esterified polymer more than 5, for example 5.5 to 50, preferably 9 to 30% of the carboxyl groups are esterified.
• the esterification itself is generally carried out at higher temperatures, for example 50 to 200, preferably 80 to 150 ° C. in the presence of customary esterification catalysts.
• P-Toluenesulfonic acid is particularly suitable as a catalyst.
• the esterification reaction is complete after about 0.5 to 20, preferably 1 to 10 hours.
• Solvents for the esterification reaction are all those organic liquids which are inert to the anhydride groups and which dissolve or swell both the starting materials and the partially esterified copolymers, for example toluene, xylene, ethylene benzene, aliphatic hydrocarbons and ketones, such as acetone and methyl ketone.
• the solvents - if they are used - are removed from the reaction mixture, for example by distillation, and the remaining partially esterified copolymers are dissolved in water with the addition of alkalis.
• the anhydride groups still present in copolymers are hydrolyzed here.
• Suitable alkalis are, for example, sodium hydroxide solution, potassium hydroxide solution, ammonia, amines and alkanolamines.
• the pH of the aqueous partially esterified copolymer solutions thus obtained is 4 to 10 and is preferably in the range of 6 to 8.
• the partially esterified copolymers to be used according to the invention are also obtainable, for example, by mono- and diesters derived from C1 to C3 alcohols, the monoethylenically unsaturated dicarboxylic acids (component (b)) with the reaction products of (A) described above and (B) partially transesterified and the transesterified products then copolymerized with at least one C4 to C28 olefin or mixtures of at least one C4 to C28 olefin with up to 20 mol% of C1 to C4 alkyl vinyl ethers.
• reaction of the mono- and diesters of the monoethylenically unsaturated dicarboxylic acids with the reaction products from (A) and (B) is only carried out to an extent which is at least 5 to 50% of the ester groups which are derived from a C1 to C3 alcohol , react.
• the reaction takes place with alkali, ammonia and / or alkanolamines to give the water-soluble salts, at least some hydrolysis of the starting mono- or diesters of C1 to C3 alcohols occurring.
• partial esterification of alternating copolymers from (a) and (b) containing anhydride groups with the reaction products of (A) and (B) is preferred in any case.
• the partially esterified copolymers to be used according to the invention can be in the form of the free acids and in partially or completely neutralized form and can be added to liquid detergents in each of these forms.
• the liquid detergent formulations which contain the partially esterified copolymers described above in an amount of 0.1 to 20, preferably 1 to 10% by weight, are usually made alkaline and have, as a further essential constituent, at least one anionic surfactant, a nonionic surfactant or their mixtures and water. These are clear aqueous solutions.
• Suitable anionic surfactants are, for example, sodium alkylbenzenesulfonates, fatty alcohol sulfates and fatty alcohol polyglycol ether sulfates.
• Individual compounds of this type are, for example, C8 to C12 alkyl benzene sulfonates, C12 to C1- alkane sulfonates, C12 to C16 alkyl sulfates, C12 to C16 alkyl sulfosuccinates and sulfated ethoxylated C12 to C16 alkanols.
• anionic surfactants are sulfated fatty acid alkanolamines, fatty acid monoglycerides or reaction products of 1 to 4 moles of ethylene oxide with primary or secondary fatty alcohols or alkylphenols.
• anionic surfactants are fatty acid esters or fatty acid amides of hydroxy or aminocarboxylic acids or sulfonic acids, such as, for example, the fatty acid sarcosides, glycolates, lactates, taurides or isothionates.
• the anionic surfactants can be in the form of the sodium, potassium and ammonium salts and also as soluble salts of organic bases, such as mono-, di- or triethanolamine or other substituted amines.
• the anionic surfactants also include the usual soaps, i.e. the alkali salts of natural fatty acids.
• Addition products of 3 to 40, preferably 4 to 20 moles of ethylene oxide with 1 mole of fatty alcohol, alkylphenol, fatty acid, fatty amine, fatty acid amide or alkanesulfonamide can be used, for example, as nonionic surfactants (nonionics).
• nonionic surfactants nonionics
• the addition products of 5 to 16 moles of ethylene oxide with coconut oil or tallow fatty alcohols, with oleyl alcohol or with synthetic alcohols with 8 to 18, preferably 12 to 18 carbon atoms, and with mono- or dialkylphenols with 6 to 14 carbon atoms in are particularly important the alkyl residues.
• non-fully or not fully water-soluble polyglycol ethers with 1 to 4 ethylene glycol ether residues in the molecule are also of interest, in particular if they are used together with water-soluble nonionic or anionic surfactants.
• non-ionic surfactants that can be used are the water-soluble adducts of ethylene oxide with 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups with polypropylene glycol ethers, alkylene diaminopolypropylene glycol and alkyl polypropylene glycols with 1 to 10 carbon atoms in the alkyl chain, in which the polypropylene glycol ether chain functions as a hydrophobic residue.
• Nonionic surfactants of the amine oxide or sulfoxide type can also be used.
• the foaming power of the surfactants can be increased or decreased by combining suitable types of surfactants. A reduction can also be achieved by adding non-surfactant-like organic substances.
• the liquid, aqueous detergents contain 10 to 50% by weight of surfactants. You can contain an anionic or nonionic surfactant in the amount specified. However, it is also possible to use mixtures of anionic and nonionic surfactants. In such a case, the content of anionic surfactants in the liquid detergent is chosen from 10 to 30% by weight and the content of nonionic surfactants in the liquid detergent from 5 to 20% by weight, based on the total detergent formulation.
• the liquid detergents contain the partially esterified copolymers to be used according to the invention in amounts of 0.1 to 20, preferably 1 to 10% by weight and water in amounts of 10 to 60, preferably 20 to 50% by weight.
• the liquid detergents may also contain other substances for modification. These include, for example, alcohols, such as ethanol, n-propanol and isopropanol. If used, these substances are used in amounts of 3 to 8% by weight, based on the total detergent formulation.
• the liquid detergents may also contain hydrotropes. This includes compounds such as 1,2-propanediol, cumene sulfonate and toluene sulfonate. If such compounds are used to modify the liquid detergent, their amount, based on the total weight of the liquid detergent, is 2 to 5% by weight. In many cases, addition of complexing agents has also proven to be advantageous for modification.
• Complexing agents are, for example, ethylenediaminetetraacetic acid, nitrilotriacetate and isoserinediacetic acid.
• the complexing agents are used in amounts of 0 to 10% by weight, based on the liquid detergent.
• the liquid detergents can also contain citrates, di- or Contain triethanolamine, opacifiers, optical brighteners, enzymes, perfume oils and dyes. If these substances are used to modify the liquid detergents, they are present in quantities of up to 5% by weight.
• the liquid detergents according to the invention are preferably phosphate-free. However, they can also contain phosphates, for example pentasodium triphosphate and / or tetrapotassium pyrophosphate. If phosphates are used, the proportion of phosphates in the total formulation of the liquid detergent is 10 to 25% by weight.
• liquid detergents described above have the advantage over the powder detergents that they are easy to dose and have very good fat and oil dissolving power at greasy soiled laundry at lower washing temperatures.
• Liquid detergents contain high levels of detergent substances, which remove dirt from the textile fabric at washing temperatures of 40 to 60 ° C.
• the dispersing properties of polymers have hitherto not been able to be used in aqueous liquid detergents because, as a result of high electrolyte concentrations in the detergents, it was not possible to obtain stable solutions with the polymers.
• With the partially esterified copolymers to be used according to the invention it is now possible to produce stable aqueous solutions of liquid detergents and to significantly improve the washing properties of liquid detergents.
• the effectiveness of the partially esterified copolymers to be used according to the invention in liquid detergents is demonstrated in the examples with the aid of the stability of the liquid detergents and the primary and secondary washing action of these detergents.
• the primary washing effect is the actual removal of dirt from the textile material.
• the degree of dirt removal is the difference in the degree of whiteness between the unwashed and the washed textile material after washing. Cotton, cotton / polyester and polyester fabrics with standard soiling are used as the textile test material. After each wash, the whiteness of the fabric in% remission is determined in an Zeiss elrephophotometer.
• Secondary washing is understood to mean the effects which arise from the re-accumulation of the dirt detached from the fabric on the fabric in the wash liquor.
• the secondary washing effect can only become visible after several washes, for example 3, 5, 10 or even only 20 washes, which is noticeable in increasing graying (redeposition), that is, dirt from the washing liquor accumulates on the fabric.
• standard soiling fabric is washed several times together with white test fabric and the soiled fabric is renewed after each wash.
• the dirt detached from the dirt fabric, which is drawn onto the white test fabric during washing causes one Decrease in whiteness that is measured.
• the partially esterified copolymers or their water-soluble salts to be used in liquid detergents according to the invention can also be used for the formulation of powder detergents.
• the percentages in the examples are percentages by weight.
• the K values were determined according to H. Fikentscher, Cellulose Chemie, Vol. 13, 58 to 64 and 71 to 74 (1932).
• the K values of the copolymers containing anhydride groups were determined in tetrahydrofuran at a temperature of 25 ° C. and a polymer concentration of 1% by weight.
• the K values of the hydrolyzed copolymers were measured in aqueous solution at 25.degree. C., a pH of 7.5 and a polymer concentration of 1% by weight.
• n-dodecene and 98 g of maleic anhydride are placed in a polymerization reactor provided with a stirrer, thermometer, cooler, nitrogen inlet and nitrogen outlet and metering devices and heated to a temperature of 100 ° C. in a gentle stream of nitrogen.
• a solution of 5 g of tert-butylethylhexanoate in 34 g of dodecene is added within 3 hours and the reaction mixture is heated to a temperature of 100 ° C. 2 hours after the initiator has been added.
• a clear solution of a copolymer in dodecene is obtained.
• the fine-grained suspension of the copolymer is then filtered off and dried in a rotary evaporator at 60 ° C. under a Pressure of 20 mbar. 1350 g of a fine white powder are obtained, which has a K value of 36.
• copolymerized maleic anhydride thus prepared copolymers are reacted with 159.6 g of an adduct which can be obtained by reacting 5 moles of propylene oxide and then 2.5 moles of ethylene oxide with one mole of a C13 / C15 oxo alcohol.
• an adduct which can be obtained by reacting 5 moles of propylene oxide and then 2.5 moles of ethylene oxide with one mole of a C13 / C15 oxo alcohol.
• 0.42 g of p-toluenesulfonic acid is used as the catalyst and 362 g of toluene are used as the diluent. This reaction mixture is refluxed for 12 hours.
• the toluene is then distilled off and 320 g of a light yellow, brittle resin are obtained, which is dissolved in a solution of 152 g of potassium hydroxide solution in 300 g of water at 80.degree.
• a highly viscous solution which is diluted by adding water to such an extent that it can be easily stirred.
• the clear, slightly yellowish solution thus obtained has a solids content of 27.6% and a pH of 7.1.
• the K value of the partially esterified copolymer is 47.5. 6.5% of the carboxyl groups of the hydrolyzed copolymer were esterified.
• Example 2 In the reactor specified in Example 1, which is operated under excess pressure, 1082 g of diisobutylene (isomer mixture of 80% trimethylpentene-1 and 20% trimethylpentene-2) and 49 g of maleic anhydride are introduced. The reactor is then closed tightly and injected with 6 bar of nitrogen. The reactor is then depressurized and pressed twice more in the white described with 6 bar of nitrogen. The contents of the reactor are then heated to 160 ° C. with stirring. 931 g of maleic anhydride are then metered in over the course of 2 hours, and a solution of 63 g of di-tert-butyl peroxide in 150 g of diisobutene is added over the course of 3 hours.
• reaction mixture is stirred at 160 ° C. for a further hour. Then 246 g of unpolymerized diisobutene are distilled off under a pressure of 100 mbar.
• the clear, golden-yellow melt obtainable in this way is emptied onto a metal sheet and, after cooling to room temperature, is present as a brittle resin which has a K value of 12.6.
• 420 g of this resin are then mixed with the amounts of alkoxylated compounds given in Table 1, which can be obtained by reacting (A) with the alkylene oxides (B), in the presence of 0.8 g of p-toluenesulfonic acid within 4 hours at 150 ° C implemented.
• Example 1 In a reactor according to Example 1, which can be operated under excess pressure, 196 g of maleic anhydride, 0.42 g of p-toluenesulfonic acid and 228 g of a reaction product of a C13 oxo alcohol with 8 moles of ethylene oxide are heated to 150 ° C. After 4 hours at 150 ° C., the reactor is tightly sealed, pressed three times with 6 bar of nitrogen and 224 g of diisobutene (isomer mixture of 80% trimethylpentene-1 and 20% trimethylpentene-2) are pumped in, a pressure of 8 bar being established.
• a solution of 12.5 g of di-tert-butyl peroxide in 50 g of diisobutene is then metered in within 4 hours and the mixture is then heated at 150 ° C. for 1 hour. The pressure is then carefully released and then the last traces of unreacted diisobutene are distilled off under vacuum. It is then cooled to 90 ° C. and 400 g of water and 222 g of 50% strength aqueous potassium hydroxide solution are metered in over the course of 0.5 hours and the mixture is reheated at 60 ° C. for 2 hours. The yellow solution obtained has a solids content of 54.3%. The K value of the end product is 15.9.
• Copolymers 1 to 14 described above were tested in the following liquid detergent formulation:
• Example 2 is a copolymer of maleic anhydride and diisobutene with a K value of 12.6 as the potassium salt
• liquid detergents are obtained which are stable in storage and which have an improved primary washing action and secondary washing action compared to a hydrolyzed, non-esterified copolymer made from maleic anhydride and diisobutene.

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• 1988
  • 1988-10-31 DE DE3837013A patent/DE3837013A1/de not_active Withdrawn
• 1989
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