WO1998017607A1 - Melange de substances solides generateur de gaz et exempt d'acide - Google Patents

Melange de substances solides generateur de gaz et exempt d'acide Download PDF

Info

Publication number
WO1998017607A1
WO1998017607A1 PCT/EP1997/005789 EP9705789W WO9817607A1 WO 1998017607 A1 WO1998017607 A1 WO 1998017607A1 EP 9705789 W EP9705789 W EP 9705789W WO 9817607 A1 WO9817607 A1 WO 9817607A1
Authority
WO
WIPO (PCT)
Prior art keywords
mixture
substances according
coolant
group
fuel
Prior art date
Application number
PCT/EP1997/005789
Other languages
German (de)
English (en)
Inventor
Achim Hofmann
Roland Schropp
Karl-Heinz Rödig
Siegfried Zeuner
Original Assignee
Trw Airbag Systems Gmbh & Co. Kg
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Trw Airbag Systems Gmbh & Co. Kg filed Critical Trw Airbag Systems Gmbh & Co. Kg
Publication of WO1998017607A1 publication Critical patent/WO1998017607A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C06—EXPLOSIVES; MATCHES
    • C06D—MEANS FOR GENERATING SMOKE OR MIST; GAS-ATTACK COMPOSITIONS; GENERATION OF GAS FOR BLASTING OR PROPULSION (CHEMICAL PART)
    • C06D5/00—Generation of pressure gas, e.g. for blasting cartridges, starting cartridges, rockets
    • C06D5/06—Generation of pressure gas, e.g. for blasting cartridges, starting cartridges, rockets by reaction of two or more solids
    • C—CHEMISTRY; METALLURGY
    • C06—EXPLOSIVES; MATCHES
    • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
    • C06B23/00—Compositions characterised by non-explosive or non-thermic constituents
    • C06B23/04—Compositions characterised by non-explosive or non-thermic constituents for cooling the explosion gases including antifouling and flash suppressing agents

Definitions

  • the invention relates to an azide-free solid mixture for the pyrotechnic generation of gases, in particular propellant gases for occupant protection devices in motor vehicles, such as Driver and / or passenger airbag systems.
  • Passive safety devices for motor vehicles serve to protect the vehicle occupants from injuries in the event of a collision of the vehicle.
  • a gas generator in a combustion chamber contains a gas-generating mixture of substances in the form of tablets, pellets or granules which, after electrical activation, generates a propellant gas which in turn inflates a gas bag, thereby preventing the vehicle occupant from hitting the windshield, the steering wheel or the like Dashboard opens.
  • gas-generating mixtures of substances Various mixtures of substances are known as gas-generating mixtures of substances.
  • sodium azide is used as the main gas-supplying component
  • potassium nitrate as the oxidizer
  • silicon dioxide as the slag former.
  • a major disadvantage of the use of fuels containing sodium azide is their high toxicity, which requires special measures, for example in the manufacture, transport and disposal.
  • Another disadvantage is the alkaline combustion residues, which can cause burns.
  • EP-A2-0659714 discloses a gas-generating composition which consists of 2 to 45% by weight of a tetrazole or triazole compound as fuel, 50 to 75% by weight of an oxidizer, 0.5 to 30% by weight of aluminum oxide and 1 to 10% by weight of a binder and, optionally, 1 to 10% by weight of a coolant selected from the group consisting of the group consisting of alkali metal and alkaline earth metal carbonates, oxalates and mixtures thereof.
  • alumina is considered necessary to the formation of an easily filterable slag to ensure with the chemically aggressive alkali metal oxides.
  • EP-Al-0509763 describes a gas-generating composition which contains a tetrazole, bitetrazole or triazole compound, an oxygen-containing oxidizer, a high-temperature slag former and a low-temperature slag former as fuel.
  • High-temperature slag formers include alkaline earth metal carbonates, in particular magnesium carbonate, which is said to decompose when the composition is burned off to form high-melting magnesium oxide.
  • Examples of low temperature slag formers are silicon dioxide, boron oxide, vanadium pentoxide, clays and talcs and alkali metal silicates, borates, carbonates, nitrates, perchlorates and chlorates.
  • EP-Al-0509763 describes a gas-generating composition which uses one of the abovementioned azole compounds as fuel, an alkali metal or alkaline earth metal nitrate and / or perchlorate as an oxidizer, an alkali metal carbonate as a chemical additive for reducing the nitrogen oxide content in the combustion products of the composition as well as a low-temperature slag former, which is selected from the group of naturally occurring clays and talcs and silicon dioxide.
  • DE-Al-19505568 finally describes a propellant for gas generators which uses at least one compound from the group tetrazoles, triazoles, triazines, cyanic acid, urea, their derivatives, derivatives or their salts, as oxidizing agents compounds from the group of peroxides, nitrates , Chlorates or perchlorates, furthermore combustion moderators, which are suitable for influencing the combustion and its speed by heterogeneous or homogeneous catalysis, as well as possibly supplements, which are suitable for reducing the proportion of toxic gases.
  • Metal oxides, metal carbonates and / or metal sulfides are mentioned as edge moderators. Examples of those for reducing the nitrogen oxide content
  • the additives used are the oxides, hydroxides or carbonates of non-toxic elements such as, for example, those of the alkali and alkaline earth metals, zinc and mixtures thereof.
  • the invention is based on the object of providing a gas-producing, azide and heavy metal-free fuel mixture which consists of non-toxic components, has a high thermal and chemical stability, is easy to process and is not hygroscopic, has a sufficiently high rate of combustion and is readily ignitable , whereby the combustion temperatures are noticeably reduced compared to known gas-generating mixtures, the proportion of gaseous fine dust particles is lower, a well filterable, condensed combustion residue is generated, the propellant gas composition is essentially harmless, the concentrations of harmful gases such as CO, N0 ⁇ in the propellant gas are as low as possible and the raw materials are as inexpensive as possible.
  • This complex problem is solved in a simple and surprisingly effective manner with a mixture of substances of the type mentioned at the beginning, which comprises a fuel, an oxidizer and a coolant selected from the group of inorganic carbonates in a proportion of at least 5% by weight in the solid mixture, and which is characterized in that the coolant is in a coarse granular form.
  • Preferred embodiments of the mixture of substances according to the invention are those in which the coolant is an alkali metal, alkaline earth metal or transition metal carbonate or a mixture of these.
  • the coolant contains calcium carbonate, magnesium carbonate, zinc carbonate, manganese carbonate, iron carbonate or a mixture of these.
  • the coolant particularly preferably contains granular marble, dolomite or magnesite.
  • the coolant has an average grain size of at least 25 ⁇ m, preferably at least 50 ⁇ m and particularly preferably between 0.1 mm and 0.8 mm.
  • the average grain size of the coolant preferred in the respective application depends on the type of carbonate used as the coolant and the grain size and structure of the respective fuel and the oxidizer. In general, the mean grain size of the coolant will be at least about five times the grain size of fuel and / or oxidizer.
  • the particularly preferred use according to the invention of alkaline earth carbonates as coolants in particular with average grain sizes in the range from 50 to 100 ⁇ m, also means that the combination of high and low temperature slag formers described in the prior art is dispensed with and nevertheless an excellent retention capacity of the combustion residues can be achieved in the gas generator without complex filter installations.
  • a particularly preferred embodiment The fuel mixture according to the invention therefore essentially consists of a fuel, an alkaline earth nitrate, chlorate and / or perchlorate as an oxidizer and a coarse-grained alkaline earth carbonate as a coolant.
  • the melting point of calcium carbonate at 100 bar is, for example, 1339 ° C.
  • the coarse grains of the alkaline earth carbonate compared to the other constituents of the solid mixture therefore form a thin molten layer on their surface, while the remaining grains, due to the very short duration of the thermal load in the range of around 40 ms and the poor thermal conductivity of the alkaline earth carbonate in its Inside stays firm.
  • the molten surface layer binds the fine dust particles resulting from the combustion of the oxidizer, so that the relatively coarse grains of the coolant with the adhering fine dust can easily be separated from the propellant gas released by the combustion.
  • the alkaline earth carbonate coolant lowers the combustion temperature and also supplies additional gas in the form of carbon dioxide from its partial decomposition.
  • the use of relatively coarse coolant grains does not undesirably reduce the burning rate.
  • the fuel mixtures according to the invention are also distinguished by excellent temperature stability, as demonstrated in storage tests at 110 ° C. for 400 hours.
  • Triazoles, tetrazoles, bitetrazoles, azotetrazoles and guanidine compounds, and their salts and mixtures, are preferably used as fuels.
  • the proportion of fuel in the solid mixture is preferably 30 to 60% by weight.
  • Azole compounds are preferably used as fuel in a proportion of 20 to 40% by weight.
  • the oxidizers can be selected from the group consisting of ammonium nitrate, ammonium perchlorate and the chlorates, nitrates and perchlorates of the alkali and alkaline earth metals and mixtures thereof.
  • triazoles in particular 5-aminotetrazole, guanylaminotetrazole, guanidiniumazotetrazole or 5-nitro-l, 2, 4, -triazol-3-one (NTO), is particularly preferred.
  • a fuel in a proportion of 20 to 40% by weight and of ammonium nitrate, ammonium perchlorate, alkaline earth nitrates and / or alkaline earth perchlorates as an oxidizer in a proportion of 40 to 60% by weight.
  • the oxidizer is particularly preferably strontium nitrate or a mixture of strontium nitrate and ammonium perchlorate with an ammonium perchlorate content of at most 10% by weight.
  • the most preferred fuel is 5-aminotetrazole mixed with guanylaminotetrazole.
  • the fuel contains a carbonate, a hydrogen carbonate, a nitrate or an organic salt of a guanidine compound or a mixture of these.
  • the guanidine compound can consist of guanidine, aminoguanidine, diaminoguanidine, triaminoguanidine, nitroguanidine or a mixture of these.
  • the fuel contains finely ground guanidine nitrate with an average grain size of less than 20 ⁇ m, preferably less than 10 ⁇ m.
  • the oxidizer is preferably a chlorate and / or a perchlorate with a proportion in the solid mixture of 10 to 60% by weight.
  • the substance mixture according to the invention additionally contains a combustion moderator and / or a slagging agent from the group of metal oxides, in particular B2O3, Al2O3, SiO2, iO2, MnO2, Fe2O3, Fe3O4, CuO, C 2O, ZnO or one Mixture of these with a proportion of up to 55 wt .-%, preferably at most 20 wt .-%.
  • These metal oxides can simultaneously act as further oxidizers.
  • the mixture of substances additionally contains a processing aid from the group of graphite, talc, bentonite, boron nitride, polyethylene glycols, magnesium stearate, zinc stearate, cellulose, methyl cellulose or a mixture of these in a proportion of up to 5% by weight.
  • a processing aid from the group of graphite, talc, bentonite, boron nitride, polyethylene glycols, magnesium stearate, zinc stearate, cellulose, methyl cellulose or a mixture of these in a proportion of up to 5% by weight.
  • the components of the mixture of substances according to the invention are non-toxic and inexpensive as well as recyclable and, moreover, very easy to process. Furthermore, with this fuel mixture according to the invention, a high burning rate is achieved with low combustion temperatures in comparison to mixtures without carbonates. Furthermore, the addition of carbonate coolants also improves the slagging behavior and the fine dust emissions. The combustion residues are non-toxic and the propellant gas itself has only minimal levels of pollutants. Finally, the fuel mixture according to the invention can also be produced free of azide and heavy metals and at low production costs.
  • 300 g of finely ground guanidine nitrate with an average grain size of approx. 9 ⁇ m and 300 g of finely ground potassium perchlorate with an average grain size of approx. 11 ⁇ m are mixed by rubbing three times through a sieve with a mesh size of 315 ⁇ m. Then 90 g of granulated marble with a grain size of 100 ⁇ m - 800 ⁇ m and an average grain size of 450 ⁇ m are added and the entire mixture e.g. homogenized in a double cone mixer.
  • the mass obtained can be pressed directly on a rotary press, as is usually used in the pharmaceutical industry, into tablets of the desired diameter.
  • 300 g of finely ground guanidine nitrate with an average grain size of approx. 7 ⁇ m and 300 g of finely ground potassium perchlorate with an average grain size of approx. 10 ⁇ m are mixed in a ball mill for 3 hours and then, as described in Example 1, compressed to tablets of the same size.
  • Table 1 below shows the percentages of the components of the respective fuel mixture and the combustion temperatures in Kelvin:
  • Table 2 below compares the emission behavior and the burn-up behavior of the mixture according to Example 1 with that of the mixture according to the comparative example:
  • the fuel mixture according to the invention has a relatively high burning rate, that is to say a short burning time, and a very much lower solids emission, in particular a much lower fine dust emission, than the mixture according to the comparative example, which contains no carbonate coolants.
  • the slagging behavior in the mixture according to the invention is thus considerably improved compared to the comparative example.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Air Bags (AREA)
  • Solid Fuels And Fuel-Associated Substances (AREA)

Abstract

Ce mélange de substances solides exempt d'acide sert à générer pyrotechniquement des gaz, notamment des gaz propulseurs de dispositifs de protection des passagers de véhicules à moteur. Le mélange comprend un combustible, un oxydant et un agent de refroidissement sélectionné dans le groupe des carbonates inorganiques. Ce mélange de substances se caractérise en ce que la proportion d'agent de refroidissement dans le mélange de substances solides s'élève à au moins 5 % en poids et se présente sous forme de grains grossiers.
PCT/EP1997/005789 1996-10-22 1997-10-21 Melange de substances solides generateur de gaz et exempt d'acide WO1998017607A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE1996143468 DE19643468A1 (de) 1996-10-22 1996-10-22 Gaserzeugendes, azidfreies Feststoffgemisch
DE19643468.8 1996-10-22

Publications (1)

Publication Number Publication Date
WO1998017607A1 true WO1998017607A1 (fr) 1998-04-30

Family

ID=7809384

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1997/005789 WO1998017607A1 (fr) 1996-10-22 1997-10-21 Melange de substances solides generateur de gaz et exempt d'acide

Country Status (2)

Country Link
DE (1) DE19643468A1 (fr)
WO (1) WO1998017607A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1195367A1 (fr) * 1999-04-30 2002-04-10 Daicel Chemical Industries, Ltd. Composition generatrice de gaz
WO2004063128A1 (fr) * 2003-01-14 2004-07-29 Ruag Ammotec Gmbh Charge propulsive
EP1538137A1 (fr) * 2002-09-12 2005-06-08 Daicel Chemical Industries, Ltd. Composition de generation de gaz

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19812372C2 (de) * 1998-03-20 2001-10-04 Nigu Chemie Gmbh Gasgeneratortreibstoffe
DE19840993B4 (de) * 1998-09-08 2006-03-09 Trw Airbag Systems Gmbh & Co. Kg Verwendung eines gaserzeugenden Gemisches als Anzündmischung in einem Gasgenerator
DE29821541U1 (de) * 1998-12-02 1999-02-18 Trw Airbag Sys Gmbh & Co Kg Azidfreie, gaserzeugende Zusammensetzung
JP4767487B2 (ja) * 2003-10-20 2011-09-07 ダイセル化学工業株式会社 ガス発生剤組成物
US20060231179A1 (en) * 2005-04-05 2006-10-19 Louise Guindon Non-toxic, metallic-boron-containing, IR tracer compositions and IR tracer projectiles containing the same for generating a dim visibility IR trace
DE102012024799A1 (de) * 2012-12-19 2014-06-26 Trw Airbag Systems Gmbh Gepresstes Treibladungselement, Verfahren zu dessen Herstellung und Gasgenerator mit Treibladungselement
KR101518316B1 (ko) * 2013-05-21 2015-05-11 주식회사 한화 인플레이터 고체 배출량이 감소된 가스발생제 조성물
CN106699489B (zh) * 2015-11-12 2019-01-11 比亚迪股份有限公司 一种用于安全气囊的产气药及其制备方法和一种汽车安全气囊用气体发生器

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB765865A (en) * 1953-01-21 1957-01-16 Ici Ltd New and improved gas-producing compositions
US2904420A (en) * 1956-08-13 1959-09-15 Ici Ltd Gas producing compositions
US3725154A (en) * 1972-06-23 1973-04-03 Us Navy Mesa burning gas generator propellant
US3862866A (en) * 1971-08-02 1975-01-28 Specialty Products Dev Corp Gas generator composition and method
US5035757A (en) * 1990-10-25 1991-07-30 Automotive Systems Laboratory, Inc. Azide-free gas generant composition with easily filterable combustion products
EP0607446A1 (fr) * 1992-07-13 1994-07-27 Nippon Koki Co., Ltd. Agent generateur de gaz pour sacs gonflables
DE4412871A1 (de) * 1993-04-15 1994-10-20 Nof Corp Zusammensetzungen für Gasgeneratoren
WO1995000205A1 (fr) * 1993-06-24 1995-01-05 Olin Corporation Appareil et procede pour combattre le feu
US5460668A (en) * 1994-07-11 1995-10-24 Automotive Systems Laboratory, Inc. Nonazide gas generating compositions with reduced toxicity upon combustion
DE19516818A1 (de) * 1994-05-09 1995-11-16 Nof Corp Gasentwickler-Zusammensetzungen
WO1996022954A1 (fr) * 1995-01-26 1996-08-01 Thiokol Corporation Procedes de preparation de formulations generatrices de gaz
DE19505568A1 (de) * 1995-02-18 1996-08-22 Dynamit Nobel Ag Gaserzeugende Mischungen

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3839105A (en) * 1972-03-10 1974-10-01 Thiokol Chemical Corp Oxalyl dihydrazide compositions and use as a coolant in gas generating process
US3880595A (en) * 1972-06-08 1975-04-29 Hubert G Timmerman Gas generating compositions and apparatus
US3897285A (en) * 1973-09-10 1975-07-29 Allied Chem Pyrotechnic formulation with free oxygen consumption
GB1443547A (en) * 1973-12-17 1976-07-21 Canadian Ind Metal oxide/azide gas generating compositions
CA1048272A (fr) * 1974-08-26 1979-02-13 Eugene F. Garner Propergol basse temperature pour generateur a gaz
US4948439A (en) * 1988-12-02 1990-08-14 Automotive Systems Laboratory, Inc. Composition and process for inflating a safety crash bag
US5051143A (en) * 1990-06-28 1991-09-24 Trw Vehicle Safety Systems Inc. Water based coating for gas generating material and method
DE4435790A1 (de) * 1993-10-06 1995-04-13 Contec Chemieanlagen Gmbh Gasgeneratortreibstoff
DE4423088A1 (de) * 1994-07-01 1996-01-04 Temic Bayern Chem Airbag Gmbh Gaserzeugendes, azidfreies Stoffgemisch

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB765865A (en) * 1953-01-21 1957-01-16 Ici Ltd New and improved gas-producing compositions
US2904420A (en) * 1956-08-13 1959-09-15 Ici Ltd Gas producing compositions
US3862866A (en) * 1971-08-02 1975-01-28 Specialty Products Dev Corp Gas generator composition and method
US3725154A (en) * 1972-06-23 1973-04-03 Us Navy Mesa burning gas generator propellant
US5035757A (en) * 1990-10-25 1991-07-30 Automotive Systems Laboratory, Inc. Azide-free gas generant composition with easily filterable combustion products
EP0607446A1 (fr) * 1992-07-13 1994-07-27 Nippon Koki Co., Ltd. Agent generateur de gaz pour sacs gonflables
DE4412871A1 (de) * 1993-04-15 1994-10-20 Nof Corp Zusammensetzungen für Gasgeneratoren
WO1995000205A1 (fr) * 1993-06-24 1995-01-05 Olin Corporation Appareil et procede pour combattre le feu
DE19516818A1 (de) * 1994-05-09 1995-11-16 Nof Corp Gasentwickler-Zusammensetzungen
US5460668A (en) * 1994-07-11 1995-10-24 Automotive Systems Laboratory, Inc. Nonazide gas generating compositions with reduced toxicity upon combustion
WO1996022954A1 (fr) * 1995-01-26 1996-08-01 Thiokol Corporation Procedes de preparation de formulations generatrices de gaz
DE19505568A1 (de) * 1995-02-18 1996-08-22 Dynamit Nobel Ag Gaserzeugende Mischungen

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1195367A1 (fr) * 1999-04-30 2002-04-10 Daicel Chemical Industries, Ltd. Composition generatrice de gaz
EP1195367A4 (fr) * 1999-04-30 2011-08-03 Daicel Chem Composition generatrice de gaz
EP1538137A1 (fr) * 2002-09-12 2005-06-08 Daicel Chemical Industries, Ltd. Composition de generation de gaz
EP1538137B1 (fr) * 2002-09-12 2016-11-09 Daicel Corporation Composition de generation de gaz
WO2004063128A1 (fr) * 2003-01-14 2004-07-29 Ruag Ammotec Gmbh Charge propulsive
US9181141B2 (en) 2003-01-14 2015-11-10 Ruag Ammotec Gmbh Propellant charge

Also Published As

Publication number Publication date
DE19643468A1 (de) 1998-04-23

Similar Documents

Publication Publication Date Title
EP0949225B1 (fr) Composition génératrice de gaz exempt d'azoture
EP0905108B1 (fr) Mélange générateur de gaz sans particules
DE69534652T2 (de) Azidfreie, gaserzeugende zusammensetzungen, die einen wärmeabsorbierenden zusatz enthalten
DE69730202T2 (de) Azidfreie, gaserzeugende zusammensetzungen
DE4412871C2 (de) Zusammensetzungen für Gasgeneratoren
DE69729750T2 (de) Gasgenerator für einen Airbag
DE19681514B4 (de) Sprengstoff-Zusammensetzung für einen Airbag und Verfahren zu ihrer Herstellung
US6533878B1 (en) Pyrotechnic compositions generating non-toxic gases based on ammonium perchlorate
EP0519485A1 (fr) Propellent pour générateurs de gaz
DE112005000805T5 (de) Gaserzeugungssystem
EP1345872B1 (fr) Composition d'agents propulseurs pour generateurs de gaz
DE19646931B4 (de) Eisenoxid als Kühlmittel und Restebildner in einer organischen gaserzeugenden Zusammensetzung
EP1006096B1 (fr) Composition génératrice de gaz exempt d'azoture
EP0691317A2 (fr) Compositions génératrices de gaz exempt d'azoture
DE102005042812B4 (de) Gasbildende Zusammensetzung
WO1998017607A1 (fr) Melange de substances solides generateur de gaz et exempt d'acide
DE19812372C2 (de) Gasgeneratortreibstoffe
EP1162183B1 (fr) Mélange d'allumage pour utilisation dans les générateurs de gaz
EP1275629B1 (fr) Composition génératrice de gaz exempt de nitrocellulose
DE102020104119A1 (de) Gaserzeugende zusammensetzung und deren verwendung in einem gasgenerator
DE60106076T2 (de) Gaserzeugung mit metallkomplexen von guanylharnstoffnitrat
DE60012933T2 (de) Zusammengesetztes, gaserzeugendes material für gasbetriebene fahrzeugsicherheitseinrichtungen
DE102012004468A1 (de) Gaserzeugende Zusammensetzung und deren Verwendung in Fußgängerschutzeinrichtungen
DE19531130A1 (de) Gaserzeugende Masse mit einem Verschlackungsmittel
EP1553071B1 (fr) Procédé de gonflage d'un sac gonflable et module de sac gonflable utilisé dans ce procédé

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP KR US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 1998518953

Format of ref document f/p: F

122 Ep: pct application non-entry in european phase