WO1996007723A1 - Compositions de nettoyage comprenant une lipase et une amylase - Google Patents

Compositions de nettoyage comprenant une lipase et une amylase Download PDF

Info

Publication number
WO1996007723A1
WO1996007723A1 PCT/US1995/011105 US9511105W WO9607723A1 WO 1996007723 A1 WO1996007723 A1 WO 1996007723A1 US 9511105 W US9511105 W US 9511105W WO 9607723 A1 WO9607723 A1 WO 9607723A1
Authority
WO
WIPO (PCT)
Prior art keywords
composition according
cleaning composition
weight
present
amount
Prior art date
Application number
PCT/US1995/011105
Other languages
English (en)
Inventor
Ian C. Callaghan
Sandra A. Palmer
Original Assignee
S.C. Johnson & Son, Inc.
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
Priority claimed from GB9417906A external-priority patent/GB9417906D0/en
Priority claimed from GBGB9504687.6A external-priority patent/GB9504687D0/en
Application filed by S.C. Johnson & Son, Inc. filed Critical S.C. Johnson & Son, Inc.
Priority to AU35830/95A priority Critical patent/AU694268B2/en
Priority to BR9508894A priority patent/BR9508894A/pt
Priority to MXPA97001728A priority patent/MXPA97001728A/es
Priority to NZ293401A priority patent/NZ293401A/en
Priority to EP95933024A priority patent/EP0779917A4/fr
Publication of WO1996007723A1 publication Critical patent/WO1996007723A1/fr

Links

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
    • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
    • C11D3/16—Organic compounds
    • C11D3/38—Products with no well-defined composition, e.g. natural products
    • C11D3/386—Preparations containing enzymes, e.g. protease or amylase
    • C11D3/38618—Protease or amylase in liquid compositions only
    • 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
    • C11D3/02—Inorganic compounds ; Elemental compounds
    • C11D3/04—Water-soluble compounds
    • C11D3/08—Silicates
    • 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
    • C11D3/38—Products with no well-defined composition, e.g. natural products
    • C11D3/386—Preparations containing enzymes, e.g. protease or amylase
    • C11D3/38627—Preparations containing enzymes, e.g. protease or amylase containing lipase

Definitions

  • This invention relates to cleaning compositions, and particularly to cleaning compositions for use on ovens.
  • Cleaning compositions have been proposed that contain active enzymes, such as washing powders and detergents. However, these compositions typically have been proposed for washing conditions appropriate for textile materials, for example temperatures below 55°C and pH's below 1 1.
  • the liquid, enzyme-based cleaning composition of the invention is summarized in that it includes a lipase enzyme active at a pH of from 10 to 14; an amylase enzyme also active at a pH of from 10 to 14; at least one alkali-stable non-ionic or anionic surfactant; an alkali metal silicate; and an inert diluent.
  • the composition is buffered at a pH of 10 to 14.
  • the method of the invention is summarized in that a method of cleaning a surface bearing burnt-on food soils includes the steps of applying the composition of claim 1 to the food soils at a cool surface temperature; allowing the food soils to soften; and removing the food soils.
  • the surface temperature does not exceed about 50°C.
  • a cleaning composition for burnt- on food soils particularly suitable for use on ovens, that is enzyme based.
  • the enzyme component is active in the pH range of 10-14. Incorporation of enzymes into cleaning compositions of this type would not normally have been considered since enzymes are known to be rather fragile and to be deactivated rather easily. It is surprising to find an enzyme-containing composition that is effective particularly at pH's in excess of 10.
  • an enzyme-based cleaning composition comprising a lipase enzyme, an amylase enzyme, an alkali-metal silicate, and an alkali-stable surfactant, which composition is buffered to maintain the pH of the composition in the range from 10-14, and preferably from 10-12.5.
  • the optimum pH is approximately 12.5.
  • the invention also provides a method of cleaning surfaces that have been subjected to food residues at high temperatures, such as ovens and other cooking surfaces, utilizing the said enzymatic composition for cleaning .
  • Lipase enzymes used in the present invention are those enzymes that promote hydrolysis of triglycerides into mono and diglycerides, glycerol, and free fatty acids, all of which are more soluble than the original fat triglyceride.
  • a number of different lipase enzymes are commercially available, having been used in fabric cleaning formulations for the removal of fat-containing stains such as the stains resulting from cooking fat, salad oils, butter, and fat based sauces.
  • a preferred lipase for use in the present invention is Lipolase, manufactured by Novo Nordisk Industry. This is a 1,3 -specific lipase that cleaves ester bonds in the positions 1 and 3 of a triglyceride.
  • Amylase enzymes are those that hydrolyze starches to soluble dextrins and oligosaccharide. Amylases have been used in fabric cleaning compositions to remove starch- containing stains, such as those made from pasta, chocolate, and gravy products, by way of example, only. Amylase enzymes hydrolyze 1 ,4-alpha glucosidic bonds in an amylose or amylopectin.
  • a preferred amylase is Termamyl® which is a commercially available enzyme manufactured by Novo Nordisk Industry, being alpha amylase prepared by fermentation of Bacillus licheniformis.
  • the composition of the invention can contain a protease as an optional, additional enzyme.
  • proteases are enzymes that hydrolyses protein to peptides that can be readily dissolved. Proteases have previously been incorporated into fabric cleaning compositions such as laundry detergents.
  • a preferred protease is the commercial product Savinase® also available from Novo Nordisk Industry. Savinase® is a proteolytic enzyme prepared by submerged fermentation of an alkalophilic species of Bacillus and is an endo-protease of the serine type, with broad substrate specificity.
  • Each of the enzymes types used are present in from 0.1 to 4% by weight of the composition.
  • the particular enzymes disclosed above are only non-limiting examples of their types. It should be noted that a wide range of commercially available lipase, amylase, and protease enzymes are available.
  • compositions of the invention are generally intended for oven cleaning, they should be of sufficient viscosity to hold them on a vertical surface for an effective time, i.e. for a time sufficient to effect or at least facilitate the removal of burnt-on food soils.
  • a thickener in addition to the other components of the composition.
  • the amount of the thickener will depend on the nature of the thickener itself and of the other components in the composition. It may be that the other components in the composition, along with their other properties, also will act as a thickener for the purpose of giving the appropriate viscosity to the composition, making unnecessary the addition of a separate component specifically as a thickener.
  • Suitable inorganic thickeners include, by way of example only, colloidal silica, smectite clays such as bentonite, attapulgite, Laponite, magnesium alumino-silicate, and compatible mixtures thereof.
  • Polymeric organic thickeners can be biopolymers (such as xanthan or welan gum) or synthetic polymers (such as polyacrylates or hydrophobically modified polyurethane). Commercially available examples of such synthetic polymers may be selected from the CARBOPOL® polymers produced by B.F. Goodrich or the RHEOVIS® polymers available from Allied Colloids.
  • the thickener is a crosslinked polyacrylate.
  • crosslinked polyacrylates may be selected from the ACRYSOL ® polymers produced by Rohm & Haas.
  • the thickener is a hydrophobically modified polyurethane thickener, it should more preferably be present in the range of from 1 to 2 percent by weight.
  • the alkali metal silicate compounds in the composition assist in fat break-down and provide alkalinity. They also assist as detergent builders and act as corrosion inhibitors. Particular alkali metal silicates that can be employed are those having a Na 2 O:SiO ratio in the range 1 :2 to 2: 1. The optimum range is from 1 : 1 to 2: 1. These alkali metal silicates will usually be present in the range 5-35 weight percent and preferably 5-25 weight percent, although the precise amount may depend on the nature of the surfactant.
  • the amount of silicate will also be determined to some extent by the nature of the buffer used.
  • the preferred buffer employing an alkali metal carbonate, and preferably sodium carbonate may allow a reduced amount of silicate to be present. Decreasing the amount of silicate present, though it cannot be reduced to 0, is advantageous in that it reduces the amount of electrolyte, which increases the shelf life of the formula.
  • silicates sometimes have adverse effects on skin, making it desirable to reduce the amount of silicates so as to minimize the side effects of the composition, should it come in contact with unprotected skin.
  • Preferred surfactants are those that are alkali stable and have an HLB (hydrophile-lipophile balance) in the range of 12-20 and preferably in the range 13-16.
  • HLB hydrophile-lipophile balance
  • the HLB is a measure of the relative water solubility of the surfactant and gives an indication of the relative proportions of hydrophobic and hydrophilic portions in the molecule.
  • the surfactants preferably are non-ionic, but anionic surfactants may be used. It is only rarely that a cationic surfactant will be operable.
  • anionic surfactants are alkaline metal and alkylolamine alkyl sulfonates, paraffin sulfonates, and alkaline metal alkyl phenol sulfonates. Normally one would use either an anionic surfactant or a non-ionic surfactant, as mixtures of anionic and non-ionic surfactants tend to be ineffective. Mixtures of surfactants are not normally compatible because of the high alkalinity, tending to separate. However, by very careful choice of the appropriate surfactant system, anionic/non-ionic surfactant mixtures are possible and are not excluded from the invention.
  • the amount of surfactant present is usually from 0.5 to 10 weight percent.
  • anionic surfactants it is also desirable that a co-builder be present, partly to assist in avoiding the salting-out of the surfactant.
  • a wide variety of co-builders are used with anionic surfactants in the various applications of these surfactants.
  • Preferred co-builders that are useful for anionic systems are alkali metal polyphosphates, alkali metal salts of organic acids, and alkali metal salts of polymeric acids. More preferably the co-builder is at least one of STPP (sodium tri polyphosphate) and alkali metal salts of citric acid, gluconic acid, polyacrylic acid, and modified polyacrylic acid.
  • the silicate component of the composition can contribute as a co-builder.
  • the co-builder (other than the silicate component) is present in the amount of 0.5-12 percent by weight.
  • Co-builders are usually less necessary in non-ionic surfactant systems since there is less likelihood of inactivation by calcium ions. Nevertheless, co-builders may still be necessary if it is found that the calcium ions present in the composition are having an adverse effect.
  • the compositions include hydrotropes, i.e. compounds that have the property of increasing the aqueous solubility of any insoluble organic chemicals present.
  • hydrotropes are cumenesulfonate, sodium zylene sulphonate, phosphate esters, and sodium toluene sulphonate.
  • Compatible mixtures of the above mentioned hydrotropes can be used if desired.
  • said hydrotropes are present in the amount of 0.2-2.5 percent by weight. Removal of burnt-on food soils can be enhanced by the use of penetrating solvents.
  • Suitable solvents are those organic liquids that soften and penetrate into resin- type materials, for example those solvents found in paints.
  • the particularly preferred solvents are those that are found also to enhance the stability of the enzymes.
  • Suitable solvents are glycol ethers (e.g. those sold under the trade name Cellosolve), esters, glycol ether acetates, methyl pyrrolidone, and l,3-dimethyl-2-imidazolidinone.
  • Compatible mixtures of the above mentioned solvents can be used. More preferably, the mentioned solvents are present in the amount of from 2-10 percent by weight.
  • compositions of the invention can contain other conventional cleaning composition components, if they do not materially detrimentally affect the enzymatic properties of the system.
  • Such components include, for example, sequestering agents, dyes, bleaches, bleach activators, foam control agents, and fragrances.
  • composition of the invention also includes appropriate diluents for application, although the composition may be prepared in a concentrated form for dilution prior to use.
  • the preferred diluent (apart from the penetrating solvents discussed above) is water and will usually comprise at least 70% and preferably at least 75% by weight of the composition.
  • composition of the invention can be applied directly without further dilution, for example by water, and can be applied by brushing or by spraying from a spray device, including an aerosol dispenser.
  • a foaming agent in the composition will result in a foam that covers the surface to be treated.
  • the surface to be treated should preferably be cold, which shall mean commonly experienced room temperatures. If warm, the surface should not be of a temperature sufficiently high as to be deleterious to the enzymes in the composition. Temperatures not in excess of 50°C are preferred.
  • Example 1 The compositions of Example 1 were viscous fluids which, when applied to the vertical walls of an oven, remained in position for sufficient time to effect cleaning. When the compositions were applied to a surface contaminated with burnt-on food soils in a test of the type recommended by the Vitreous Enamel Council, the soils softened and were easily removable after 16 hours.
  • EXAMPLE 2 The following were combined in the stated percentages by weight.
  • the composition described in Column A is an example of a specific formulation that has been made, while Column B states the preferred ranges of ingredients:
  • Example 2 The composition of Example 2 was a viscous fluid which, when applied to the vertical walls of an oven, remained in position for sufficient time to effect cleaning. When applied to a surface contaminated with burnt-on food soils in a test of the type recommended by the Vitreous Enamel Council, the soils softened and were easily removable after 16 hours.
  • the invention is not limited to the Examples, which are only illustrative. Instead, the invention is in accordance with the claims.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Wood Science & Technology (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Detergent Compositions (AREA)

Abstract

L'invention concerne une nouvelle composition liquide de nettoyage enzymatique pour enlever les débris alimentaires ayant subi un chauffage tels que ceux que l'on trouve dans les fours, et un procédé d'application de la composition sur une surface froide portant de tels débris alimentaires. La composition comprend des enzymes qui sont actifs dans la plage de pH allant de 10 à 14, et comprend un mélange d'une lipase et d'une amylase et, le cas échéant, d'une protéase. La composition contient également un silicate de métal alcalin. La composition contient de préférence un tensioactif non ionique et est tamponnée.
PCT/US1995/011105 1994-09-06 1995-09-06 Compositions de nettoyage comprenant une lipase et une amylase WO1996007723A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
AU35830/95A AU694268B2 (en) 1994-09-06 1995-09-06 A cleaning composition comprising lipase and amylase enzymes
BR9508894A BR9508894A (pt) 1994-09-06 1995-09-06 Composição de limpeza baseada em enzima líquida e processo de limpeza de uma superficie transportando sujeiras de alimento queimadas
MXPA97001728A MXPA97001728A (es) 1994-09-06 1995-09-06 Una composicion de limpieza que comprende enzimas de lipasa y amilasa.
NZ293401A NZ293401A (en) 1994-09-06 1995-09-06 Liquid enzyme-based cleaning composition buffered at ph 10-14 and comprising lipase, amylase, surfactant, alkali metal silicate and optionally protease
EP95933024A EP0779917A4 (fr) 1994-09-06 1995-09-06 Compositions de nettoyage comprenant une lipase et une amylase

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
GB9417906A GB9417906D0 (en) 1994-09-06 1994-09-06 Cleaning compositions
GB9417906.6 1994-09-06
GB9504687.6 1995-03-08
GBGB9504687.6A GB9504687D0 (en) 1995-03-08 1995-03-08 Cleaning compositions

Publications (1)

Publication Number Publication Date
WO1996007723A1 true WO1996007723A1 (fr) 1996-03-14

Family

ID=26305571

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1995/011105 WO1996007723A1 (fr) 1994-09-06 1995-09-06 Compositions de nettoyage comprenant une lipase et une amylase

Country Status (8)

Country Link
EP (1) EP0779917A4 (fr)
AU (1) AU694268B2 (fr)
BR (1) BR9508894A (fr)
CA (1) CA2199260A1 (fr)
GB (1) GB2294942B (fr)
MX (1) MXPA97001728A (fr)
NZ (1) NZ293401A (fr)
WO (1) WO1996007723A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000004119A1 (fr) * 1998-07-16 2000-01-27 Reckitt Benckiser Inc Compositions de nettoyage et leur utilisation pour le nettoyage de taches sur des vetements et des textiles
AU2001281583B2 (en) * 2000-08-22 2004-12-16 Onebiosci Pty Limited Anti-graffiti paint formulations and removal

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8420586B2 (en) 2008-04-18 2013-04-16 Ecolab Usa Inc. Thickened oven cleaner comprising a glutamic acid salt or disodium ethanol diglycine chelant
US8329630B2 (en) 2008-04-18 2012-12-11 Ecolab Usa Inc. Ready to use thickened degreaser and associated methods
CN104781297B (zh) 2012-09-04 2019-05-14 路博润先进材料公司 用于在家居护理中的光泽应用的聚氨酯/聚丙烯酰混杂物分散体

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4906396A (en) * 1986-02-20 1990-03-06 Albright & Wilson Limited Protected enzyme systems
US5066749A (en) * 1990-09-11 1991-11-19 National Starch And Chemical Investment Holding Corporation Hydrophobically-modified polycarboxylates and process for their preparation
US5230822A (en) * 1989-11-15 1993-07-27 Lever Brothers Company, Division Of Conopco, Inc. Wax-encapsulated particles
US5435936A (en) * 1993-09-01 1995-07-25 Colgate Palmolive Co. Nonaqueous liquid microemulsion compositions

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8629537D0 (en) * 1986-12-10 1987-01-21 Unilever Plc Enzymatic dishwashing composition
GB8923788D0 (en) * 1989-10-23 1989-12-13 Unilever Plc Enzymatic detergent compositions and their use
AU655274B2 (en) * 1991-05-31 1994-12-15 Colgate-Palmolive Company, The Nonaqueous liquid, phosphate-free, improved automatic dishwashing composition containing enzymes
HU219162B (hu) * 1993-07-23 2001-02-28 The Procter And Gamble Company Rövid szénláncú felületaktív anyagokat tartalmazó, javított tisztító hatású viszkózus, vizes mosószerkészítmény és alkalmazása

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4906396A (en) * 1986-02-20 1990-03-06 Albright & Wilson Limited Protected enzyme systems
US5230822A (en) * 1989-11-15 1993-07-27 Lever Brothers Company, Division Of Conopco, Inc. Wax-encapsulated particles
US5066749A (en) * 1990-09-11 1991-11-19 National Starch And Chemical Investment Holding Corporation Hydrophobically-modified polycarboxylates and process for their preparation
US5435936A (en) * 1993-09-01 1995-07-25 Colgate Palmolive Co. Nonaqueous liquid microemulsion compositions

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP0779917A4 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000004119A1 (fr) * 1998-07-16 2000-01-27 Reckitt Benckiser Inc Compositions de nettoyage et leur utilisation pour le nettoyage de taches sur des vetements et des textiles
US6670316B2 (en) 1998-07-16 2003-12-30 Reckitt Benckiser Inc. Spot pretreatment compositions
AU2001281583B2 (en) * 2000-08-22 2004-12-16 Onebiosci Pty Limited Anti-graffiti paint formulations and removal

Also Published As

Publication number Publication date
GB9518214D0 (en) 1995-11-08
MXPA97001728A (es) 2004-12-03
AU694268B2 (en) 1998-07-16
NZ293401A (en) 1998-02-26
GB2294942B (en) 1998-07-29
AU3583095A (en) 1996-03-27
BR9508894A (pt) 1997-11-18
GB2294942A (en) 1996-05-15
EP0779917A4 (fr) 1999-03-17
CA2199260A1 (fr) 1996-03-14
EP0779917A1 (fr) 1997-06-25

Similar Documents

Publication Publication Date Title
US7183248B2 (en) Enzymatic cleaner having high pH stability
EP0701601B1 (fr) Nettoyant epaissi pour surfaces dures
US5173207A (en) Powered automatic dishwashing composition containing enzymes
US4162987A (en) Enzyme-containing automatic dishwashing detergent composition
US7153817B2 (en) Detergent tablet
EP0139329B1 (fr) Compositions pour laver la vaisselle
US5698507A (en) Nonaqueous gelled automatic dishwashing composition
US5030377A (en) Detergent compositions containing starch debranching enzymes
US5551990A (en) Enzymatic dishwashing and rinsing composition
GB2116198A (en) Detergent dish-washing composition
US4931217A (en) Automatic dishwashing detergent comprising quaternary ammonium salt
US5169553A (en) Nonaqueous liquid, phosphate-free, improved automatic dishwashing composition containing enzymes
US6331512B1 (en) Phosphate-free automatic dishwashing detergent
AU694268B2 (en) A cleaning composition comprising lipase and amylase enzymes
EP0793439B1 (fr) Procede de lavage industriel de vaisselle sans agent de blanchiment
CA2069853A1 (fr) Composition detergente granulaire renfermant phosphates et enzymes, pour lave-vaisselle automatique
AU687536B2 (en) Stable enzyme-containing aqueous laundry prespotting composition
CA2134836A1 (fr) Composition en poudre pour lave-vaisselle automatique, contenant des enzymes
CA2069849A1 (fr) Composition detergente en poudre renfermant des phosphates et des enzymes pour lave-vaisselle automatique
JPH1161181A (ja) 自動食器洗浄機用洗浄剤組成物
US5693602A (en) Spray dried powered automatic dishwashing composition containing enzymes
JP3193821B2 (ja) 自動食器洗浄機用洗浄剤組成物
JPH1161179A (ja) 自動食器洗浄機用洗浄剤組成物
CN117377758A (zh) 酶反应促进方法
JP2006036928A (ja) 自動食器洗浄機用洗浄剤組成物

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU BR CA MX NZ US

AL Designated countries for regional patents

Kind code of ref document: A1

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

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
ENP Entry into the national phase

Ref document number: 2199260

Country of ref document: CA

Ref country code: CA

Ref document number: 2199260

Kind code of ref document: A

Format of ref document f/p: F

WWE Wipo information: entry into national phase

Ref document number: 1995933024

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 293401

Country of ref document: NZ

WWP Wipo information: published in national office

Ref document number: 1995933024

Country of ref document: EP

ENP Entry into the national phase

Ref country code: US

Ref document number: 1997 793963

Date of ref document: 19970714

Kind code of ref document: A

Format of ref document f/p: F

WWW Wipo information: withdrawn in national office

Ref document number: 1995933024

Country of ref document: EP