JPH04234000A - Liquid detergent composition containing protease - Google Patents

Abstract

PURPOSE: To obtain the subject composition containing a surfactant, a builder, a protease enzyme added in an amount sufficient to exhibit a specified activity level, propionic acid, water and trace components, having a pH higher than the neutrality and markedly enhanced in the stability of the protease.

CONSTITUTION: About 5 to 65 wt.% surfactant (e.g. anionic surfactant) is mixed with about 0.5-50 wt.% builder (e.g. sodium tripolyphosphate), a protease enzyme (e.g. bacterial subtilisin-type protease) added in an amount sufficient to exhibit an activity level of 0.01-200,000 GU/g and about 0.1-15 wt.% propionic acid or a propionate capable of forming propionic acid and trace components in water to obtain a stable aqueous enzyme-type detergent composition having a pH of above 7.0. It is desirable that the trace components added are about 0.1-5% deflocculating polymer and 0.01-1 wt.% calcium salt.

COPYRIGHT: (C)1992,JPO

Description

[Detailed description of the invention]

TECHNICAL FIELD This invention relates to liquid detergent compositions, and more particularly to built-in detergent compositions.
The present invention relates to the stabilization of proteases in aqueous detergent compositions enriched with anionic active agents.

BACKGROUND AND PRIOR ART The use of proteases in heavy duty liquid detergent formulations (HDLS) is complicated by their limited stability in solution. There are two processes that limit the shelf life of proteases in aqueous liquid detergents: denaturation and autolysis. Significant efforts have been made to stabilize enzymes in aqueous liquid detergent compositions, in which the medium has been shown to be problematic in retaining enzyme activity throughout storage and distribution. There is.

Denaturation of proteases can be minimized by selection of formulation components (ie, activators, builders, pH, etc.) to achieve acceptable enzyme stability. Protease autolysis can be minimized by including protease inhibitors. The inhibitor desorbs from the enzyme when diluted in wash water.

Various protease inhibitors are known in the art. For example, US-A-4 261 868 (
Unilever) taught the use of borax as a protease inhibitor and published US-A-4 243 546 (Dr.
ackett) and GB-A-1 No. 354 761 (H
both teach the use of carboxylic acids as protease inhibitors. Various combinations of these protease inhibitors are also known in the art. For example, US-
A-4 305 837 (Procter & Ga.
mble) teaches the combination of carboxylic acids and simple alcohols, and US-A-4 404 115 (Uni
Lever) teaches a combination of borax and polyol as a protease inhibitor. US-A-4 537
No. 707 (Procter & Gamble) teaches a combination of borax and carboxylate salts as protease inhibitors.

As mentioned above, the use of carboxylic acid salts as protease inhibitors in detergent compositions is known. In US-A-4 318 818, for example:
Stabilized liquid enzyme compositions are taught in which the inhibitor is a short chain carboxylate salt selected from the group consisting of formate, acetate, propionate, and mixtures thereof. According to the teachings of this patent, formate is surprisingly much more effective than other short chain salts such as acetate and propionate. The cited reference also teaches that only formate salts can be used in the pH range above 8.5. The detergent compositions used in this patent are unbuilt, ie, do not contain builders.

[0006] US-A-4 243 546 (Dra
ckett) teaches an aqueous enzyme composition in which the enzyme stabilizer is selected from the group consisting of monobasic and dibasic acids having 1 to 18 carbon atoms. Acetic acid is said to be preferred. The compositions of this invention are also builder-free. The original goal of this patent appears to be compositions with a pH below 8 (many of the examples have a pH of 7.5), with one example having a pH of 9.5 requiring the presence of an alcohol (ethal). It seems that there are. Moreover, this composition not only does not contain much anionic active agent, it appears to contain no anionic active agent at all.

[0007] GB-A-1 No. 354 761 (Hen
kel) may contain carboxylic acids of 2 to 8 carbons. All of the examples show the use of acetic acid, and the detergent compositions of this invention are also builder-free.

[0008] Thus, when carboxylic acid stabilizers are used in the prior art, 1-2 carbon carboxylic acids (acetates and formates) are preferred. When compositions with high pH (i.e. greater than 8.5) are used in the prior art, the use of formates is indicated (as in US-A-4 318 818) or carboxylic acids are combined with alcohols. or in an environment that does not contain many anionic activators, or
It's either. Prior art compositions are also non-constructed and do not recognize the importance of using compositions rich in anionic active agents with certain stabilizers.

Existing aqueous enzyme-based liquid laundry detergents are typically formulated using stabilized aqueous liquid enzyme concentrates as additives. G. Jensen highlighted the difficulty of formulating built-in liquid detergent compositions containing proteolytic enzymes in Tenside 27 (1
), page 30 (1990). It is stated that such products require special types of enzymes to obtain satisfactory storage stability. Conventional liquid enzymes (i.e. aqueous concentrates and non-aqueous slurries) are
Activity decreases very quickly due to denaturation of the enzyme protein structure by the alkaline components and sequestrants present in the composition. To solve this problem, the author believes that it is necessary to use a protected enzyme system comprising a dispersion of enzymes in a silicone matrix, a so-called silicone slurry. The example given is a liquid detergent product containing a phosphate builder and a proteolytic enzyme in the form of a slurry, but the enzyme stability is actually low.

The applicant has proposed that the composition has a pH greater than 7.0, preferably greater than 8.5, more preferably greater than 9.0, contains a builder (built form), and preferably has anionic activity. If the composition contains a large amount of
It has been unexpectedly discovered that the use of propionate rather than acetate or formate improves enzyme stability compared to other carboxylic acid stabilizers (ie, acetate or formate).

Furthermore, adding the enzyme to the formulation as a slurry of the enzyme in a non-ionic detergent, which is usually liquid,
It is surprising to find that improved enzyme stability can be achieved in aqueous liquid detergent concentrates.

Definition of the Invention Accordingly, the present invention comprises (a) about 5 to about 65% by weight surfactant, (b) about 0.5 to about 50% by weight builder, (c
(d) an amount of added protease enzyme sufficient to have an activity level of from 0.01 to about 200,000 GU/g; (d) from about 0.1 to about 15% by weight propionic acid or a propionate salt capable of forming propionic acid; , the remainder being water and minor components, and the pH of the composition is greater than 7.0.
A stable aqueous enzyme detergent composition is provided. Preferably,
The pH of the composition is greater than 8.5, more preferably
It is 9.0 or more.

The present invention also provides a method for producing such an aqueous liquid enzyme-based detergent composition. In this method, the proteolytic enzyme is preferably added in the form of a slurry of the enzyme in a liquid ionic surfactant.

DETAILED DESCRIPTION OF THE INVENTION Cleaning Active Compositions of the present invention contain from about 5% to about 65% by weight of (a)
an anionic surfactant, or (b) an anionic surfactant and one or more detersive actives, the weight ratio of anionic to nonionic active being greater than 1:1.

[0015] Detergents other than anionic surfactants include:
Can be alkali metal soaps or alkanolamine soaps, or fatty acids of 10 to 24 carbon atoms, including polymerized fatty acids, or nonionic, cationic, zwitterionic, or amphoteric synthetic detergent materials, or mixtures of any of these. .

Examples of anionic synthetic detergents are alkylbenzene sulfonates of 9 to 20 carbons, primary or secondary alkanesulfonates of 8 to 22 carbons, 8 to 22 carbons,
Sulfonated polycarboxylic acids (e.g. GB-A-
1 082 179), alkyl sulfates of 8 to 22 carbons, alkyl polyglycol ethers of 8 to 24 carbons sulfates, carboxylates and phosphates (
(containing up to 10 moles of ethylene oxide) (including substituted ammonium salts such as sodium, potassium, ammonium, and mono-, di-, and tri-ethanolamine salts). Other examples include Schwartz
, Perry and Berch, “Surface
Active Agents and Detergation
ents” (Volumes I and II). Any suitable anionic active agent may be used, but the examples are not intended to be limiting in any way.

Examples of nonionic synthetic detergents that can be used in the present invention are ethylene oxide, propylene oxide and/or butylene oxide, alkylphenols of 8 to 18 carbons, primary or secondary detergents of 8 to 18 carbons. It is a condensation product of fatty acid amides of 8 to 18 carbons. Other examples of nonionic activators include 8-
Mention may be made of tertiary amine oxides having one alkyl chain of 18 carbons and two alkyl chains of 1 to 3 carbons. Further examples of nonionic surfactants are also described in the cited document.

The average number of moles of ethylene oxide and/or propylene oxide present in the nonionic activator varies from 1 to 30. Mixtures of various nonionic active agents may also be used, including mixtures of lightly and highly alkoxylated nonionic active agents. 3-9 EOs
Ethoxylated C12-C15 fatty alcohols with - groups are preferred, with 5 to 7 EO- groups being particularly preferred.

Examples of cationic detergents are quaternary ammonium compounds such as alkyldimethylammonium halides.

Examples of amphoteric or zwitterionic detergents that can be used in the present invention are N-alkyl amino acids, sulfobetaines, condensation products of fatty acids and protein hydrolysates, but since they are relatively expensive, Usually used in combination with anionic or nonionic detergents. Mixtures of various types of active detergents may also be used, with mixtures of anionic and nonionic detergent actives being preferred. Fatty acid soaps (in the form of their sodium, potassium and substituted ammonium salts) may also be used, preferably together with anionic and/or nonionic synthetic detergents.

Among the compositions of the invention are, for example, aqueous liquid detergents with homogeneous physical properties, for example they consist of a micellar solution of a surfactant in a continuous aqueous phase, a so-called isotropic liquid. obtain.

Alternatively, they may have a heterogeneous physical phase, and they can be structured, for example into highly peptized polymers with a hydrophilic backbone and at least one hydrophobic side chain. molecules
EP-A-346 995 (U.
nilever) (incorporated herein by reference). These liquid phases may be heterogeneous and contain suspended solid particles, such as particles of builder materials of the type described below.

Builders Builders that can be used in the present invention include conventional alkaline detergency builders, which may be inorganic or organic, and range from about 0.5% to about 50%, preferably 3% by weight of the composition.
It can be used in amounts from % to 35% by weight. More specifically, when using unstructured compositions, the preferred amount of builder is from 3 to 10%, and when using structured compositions, the preferred amount of builder is from 5% to 35% by weight. be.

By structured liquid composition is meant a composition in which at least some of the cleaning active agent forms a structured phase. Preferably, such structured phase is capable of suspending solid particulate material.

More specifically, in the case of structured liquids, the composition requires sufficient electrolyte to cause the formation of lamellar phases by the surfactant in order to provide solids suspension ability. The particular type and amount of electrolyte to do so when selecting a given surfactant is selected using methodologies familiar to those skilled in the art. It utilizes specific techniques described in an extensive literature. One such approach requires conductivity measurements. Methods for detecting the presence of such lamellar phases are also well known and can be carried out, for example, by optical and electron microscopic examinations or by X-ray diffraction, and confirmed by conductivity measurements.

The term electrolyte as used herein means a water-soluble salt. The amount of electrolyte must be sufficient to cause the formation of a lamellar phase by the surfactant to provide solids suspension ability. Preferably the composition comprises at least 1.0% by weight electrolyte, more preferably at least 5.0% by weight, most preferably at least 17.0% by weight electrolyte.
Including weight %. The electrolyte may be a detergency builder, such as the inorganic builder sodium tripolyphosphate. Alternatively, it may be a non-functional electrolyte such as sodium sulfate or sodium chloride. Preferably, the inorganic builder constitutes all or part of the electrolyte.

Although systems in which the particulate solids are actually in suspension are particularly preferred, structured compositions of this type have the ability to suspend such solids. The solid may be an undissolved electrolyte and may be the same or different from the electrolyte in a solution that is saturated with electrolyte. Additionally, or alternatively, the solid can be a material that is substantially insoluble only in water. Examples of such substantially insoluble materials are aluminosilicate builders and calcite abrasives.

Examples of suitable inorganic alkaline detergency builders that can be used (in structured or unstructured compositions) are the water-soluble alkali metal salts of phosphoric acid, polyphosphoric acid, boric acid, silicic acid and carbonic acid. Particular examples of salts of this type are sodium and potassium triphosphates, pyrophosphates, orthophosphates, hexaphosphates, tetraborates, silicates and carbonates.

Examples of suitable organic alkaline detergency builder salts include (1) water-soluble aminopolycarboxylic acid salts such as sodium and potassium ethylenediaminetetraacetate, nitrilotriacetate and N-(2-hydroxyethyl);
- nitrilodiacetate, (2) water-soluble salts of phytic acid, such as sodium and potassium phytate (US-A-
2 379 942), (3) water-soluble polyphosphate (see
In particular, the sodium, potassium and lithium salts of ethane-1-hydroxy-1,1-diphosphonic acid; the sodium, potassium and lithium salts of methylene diphosphonic acid; the sodium, potassium salts of ethylene diphosphonic acid; and the sodium, potassium and lithium salts of ethane-1,1,2-triphosphonic acid. Other examples include ethane-2-carboxy-1,1-diphosphonic acid, hydroxymethanediphosphonic acid, carboxydiphosphonic acid, ethane-1-hydroxy-1,1,2-triphosphonic acid, ethane-2-hydroxy -1,1,2-triphosphonic acid, propane-1,
1,3,3-tetraphosphonic acid, propane-1,1,2
, 3-tetraphosphonic acid, and propane-1,2,2,
Examples include alkali metal salts of 3-tetraphosphonic acid. (4) Water-soluble salts of polymers and copolymers of polycarboxylic acid salts as described in US-A-3 308 067.

Additionally, polycarboxylate builders can be suitably used, including the water-soluble salts of mellitic acid, citric acid, and carboxymethyloxysuccinic acid, and the polymeric salts of itaconic acid and maleic acid.

Certain zeolites or aluminosilicates can be used. One such aluminosilicate useful in the compositions of the present invention is an amorphous water-soluble hydrated compound, the amorphous material comprising about 50 mg equivalent CaCOg
/g or more Mg++ exchange capacity and about 0.01μ to about 5
Characterized by a particle size of μ. This ion exchange builder is more fully described in GB-A-1 470 250.

Another water-soluble synthetic aluminosilicate ion exchange material useful in the present invention is crystalline in nature and has the formula N
az [(AlO2)y・(SiO2)]・x
H2O (wherein Z and y are integers of at least 6, the molar ratio of z and y is in the range of about 1.0 to about 0.5, and x is an integer of about 15 to about 264) have). The aluminosilicate ion exchange material has a diameter of about 0.1μ to about
CaC having a particle size of 100 microns and a calcium ion exchange capacity of at least about 200 mg equivalent per gram on an anhydrous basis;
O3 hardness and a calcium exchange rate of at least about 2 grains/gallon/minute/g on an anhydrous basis. GB-A-1 for these synthetic aluminosilicates
429 143 in more detail.

Enzyme The proteolytic enzyme used in the present invention can be of plant, animal or microbial origin. Preferably, it is of the latter origin and may include yeasts, fungi, molds and bacteria. Particularly preferred are bacterial subtilisin-type proteases, such as B. subtilis.
) and Bacillus licheniformis (B. Lich
eniformis). Examples of suitable proteases available commercially include Alcalas
e, Savinase, Esperase (more than N
OVO Industry A/S), Maxatas
e and Maxacal (Gist-Brocades
), Kazusase (Showa Denko); subtilisin BPN' and protease derived from subtilisin BPN'.

[0034] For any of the enzymes mentioned above, extraction of the gene and production of suitable producing organisms is possible.
Genetic engineering can be carried out by introducing and expressing a gene or derivative thereof into a human organism. EP-A-130 No. 756 (Genentech),
EP-A-214 No. 435 (Henkel),
WO 87/04461 (Amgen), WO
No. 87/05050 (Genex), EP-A-40
5 901 (Unilever) and EP-A-30
No. 3,761 (Genentech) describes useful modified subtilisin proteases.

[0035] The amount of proteolytic enzyme contained in the composition is
0.01-200,000G based on final composition
U/g, preferably 1 to 100,000
GU/g, most preferably 1000-50,00
It is in the range of 0 GU/g. Naturally, different proteolytic enzymes may be used.

GU is glycine unit, 1 μg/ml
The amount of protease produced under standard culture conditions is the amount of one terminal NH2 group corresponding to glycine.

The proteolytic enzyme is usually added in the form of a concentrated aqueous solution. However, it has been found that further improvements in the stability of proteolytic enzymes in the aqueous liquid detergent concentrates of the present invention can be achieved by adding the enzyme to the formulation as a slurry of the enzyme in a non-ionic detergent, which is usually liquid. It's amazing.

Co-pending European patent application 9120 of the applicant
No. 0677.2 (incorporated herein by reference), enzyme slurries are made by suspending, for example, powders or particles in a non-aqueous (non-ionic) liquid surfactant, especially one that is substantially anhydrous. Contains the enzyme in dispersed form. The enzyme particles may, for example, be spray-dried or freeze-dried, and they may be pulverized after spray-drying and before being dispersed in the (eg, anhydrous) non-ionic liquid detergent. Alternatively, the enzyme may be dispersed in a non-ionic detergent and then finely ground.

[0039] The amount of enzyme in the slurry is about 0.5 to about 5
0% by weight, such as from about 1 to about 20%. The enzyme slurry used to prepare the compositions of the invention will typically be substantially anhydrous, with a water content of about 1
0% or less, preferably about 5% w/w or less, sometimes about 1
% or less. Using this slurry method, it is possible to use a virtually anhydrous liquid nonionic surfactant as the continuous phase of the slurry. The liquid state of the slurry allows for thorough mixing of the enzymes in the final liquid detergent and facilitates release of the enzymes after dilution of the liquid detergent in the wash liquor.

Stabilizers As mentioned above, as stabilizers used in the subject invention, propionic acid, either pure or as a salt, is used in compositions containing about 0.0% of propionic acid.
It is added in an amount of 1 to about 15%.

It is within the scope of the present invention to incorporate further stabilization systems to the enzyme, and for this purpose in conjunction with Enzyme Stabilization (which is expressly incorporated herein by reference) It is possible to use the measures described in the specification identified by the abovementioned numbers.

For example, an amount of an enzyme stabilizing system selected from (a) an enzyme stabilizing system consisting of calcium and formate or acetate, and (b) a polyol and borate-containing enzyme stabilizing system can be included.

2-25% w/w of a polyol, such as glycerol or propylene glycol or another polyol, is used with 2-15% w/w of sodium borate or borax, for example as described in EP-A-080 223 (Unilever). ) (incorporated herein by reference)
It can be incorporated into the composition according to the following.

Additionally or alternatively, low molecular weight monocarboxylic acid salts (in salt or acid form) such as formates or acetates (
0.1-10%), enzyme-accessible calcium ions (0.1-1 mmol/kg) and lower alcohols, such as ethanol or propylene glycol (up to 20%), e.g. EP-A-028 865 (
Procter & Gamble) (incorporated herein by reference).

There is also nothing wrong with using smaller amounts of these stabilizers than indicated in the above-cited specifications.

Calcium Salts The compositions of the present invention may also include calcium salts used to provide free calcium ions to the solution. Calcium ions alone or in combination with propionate stabilize the enzyme. Examples of calcium salts that can provide free calcium ions include calcium chloride dihydrate and calcium sulfate. The calcium salt is present in the composition at 0.0%.
01-1%, preferably 0.01-0.2%
%, most preferably from 0.03 to 0.1%.

Optional Ingredients In addition to the essential ingredients described herein, preferred compositions of the invention often contain a series of optional ingredients conventionally used for known functions. The composition of the present invention is based on an aqueous enzyme-containing detergent composition;
It is often desirable to use an ase regulant. This component together with water constitutes the solvent matrix for the liquid composition of the invention. Suitable phase modifiers are well known in the liquid detergent art and include, for example, salts of alkylaryl sulfonates having up to 3 carbon atoms in the alkyl group, such as xylene, toluene, ethylbenzene, cumene, etc. Hydrotropes such as the sodium, potassium, ammonium and ethanolamine salts of - and isopropylbenzene-sulfonic acids are representative. Alcohols may also be used as phase modifiers. This phase modifier is often about 0.5%
~20%, with the total phase modifier and water typically in the range of 35% to 65%. Preferred compositions of the invention may include a series of other optional ingredients, often used in additive-level amounts, typically about 5% or less. Examples of similar additives include polyacids, suds regnants, opacifiers, antioxidants, fungicides, dyes, fragrances, brighteners, and the like.

Advantageous utilization of the compositions of the present invention under various conditions of use may require the use of foam control agents. While any detergent foam control agent may generally be utilized, preferred for use in the present invention are alkylated polysiloxanes, such as dimethylpolysiloxane, often referred to as silicones. Silicone is 0.5%
It is often used in amounts not exceeding 0.01% or more.
Most preferred is between 0.2%.

[0049] It may also be desirable to use an opacifying agent insofar as it helps impart a uniform appearance to concentrated liquid detergent compositions. Examples of suitable opacifiers include:
MONSANTO CHEMICAL CORPORA
Mention may be made of the polystyrene known on the market as LYTRON 621 manufactured by TION. Opacifiers are often used in amounts of 0.3% to 1.5%. Compositions of the present invention may include known antioxidants for their known efficacy, and often radical scavengers in amounts established in the art, i.e. 0.00
Included at 1% to 0.25% (based on the total composition). These antioxidants are often mixed in with fatty acids.

Another optional component that may be used, particularly in structured liquids, is a peptizing polymer. Generally, peptizing polymers are described in EP-A-346 995 (Unilever)
(incorporated herein by reference), consisting of a hydrophobic main chain and one or more hydrophobic side chains. They allow for the incorporation, if desired, of larger amounts of surfactant and/or electrolyte than would otherwise be compatible with the requirements for a stable, low viscosity product, as well as In this case, the lamellar dispersion is made compatible with larger amounts of other stability-sensitive components.

[0051] If a peptizing polymer is used, it generally comprises from about 0.1 to about 5% of the composition, preferably 0.1% to about 5% of the composition.
to about 2%, more preferably about 0.5 to about 1.5%.

Product pH The pH of the liquid detergent composition of the present invention can be selected from a wide range. For example, a slightly alkaline range of pH about 7 to about 12, for example pH about 7.5 to about 9.5,
or a strongly alkaline pH range of about 8.5 to about 11.5, preferably 8.5 to 11, preferably 9 to 10.
5 is most preferred.

[0053]

EXAMPLES The following examples are intended to illustrate and facilitate understanding of the invention and are not meant to limit the invention in any way.

The following abbreviations are used in the examples:

LAS Linear C12-Alkylbenzene Sulfonate Sodium LES Lauryl Ether Sulfate Nonionic Agent Ethoxylated C12-C15 Fatty Alcohol Compositions of the Invention Compositions of the invention are as follows.

Composition A (isotropic unstructured composition) Components
Weight LA
S
10.0 Non-ionic agent (9EO) (Neodol 25-9)
8.0LES (Neodol 25-3
S)
6.0 Sodium xylene sulfonate
3.0 builder

7.0 Triethanolamine
2
．． 0 monoethanolamine
2.0 fatty acids

0.8 protease (Savi
nase)
0.38 gNaOH

Carboxylic acid stabilizer (Na-salt) to adjust pH to 10
0.31 Molar concentration* Calcium chloride dihydrate
0.035 water

Set to 100%.

*0.31 molar concentration is for formate 2.
1% by weight, corresponding to 2.6% by weight for acetate and 3.0% by weight for propionate.

Composition B (structured, builder-containing composition)
Ingredients
Weight LAS

6.72 Non-ionic agents (average 5
E.O.)
4.8 Sodium xylene sulfonate
0.8 builder

23.85 Alkali metal salts

2.44 Protease
0
．． 38 Trace ingredients + water
Carboxylic acid stabilizer to 100%
0.31 molar concentration*
calcium chloride dihydrate
0.1pH

8.4* Formate 2.1% by weight, acetate 2.6% by weight or propionate 3.0
Corresponds to %. Composition C (structured, builder-containing composition)
Ingredients
Weight LAS

16.5 nonionic agent (average 5EO
) 9
．． 0 builder
23.23
fatty acid
4.5 Alkali metal salts
10.5 Peptizing polymer

1.0 protease

0.38 Trace components + water
Carboxylic acid stabilizer to 100%
0.31 molar concentration*
calcium chloride dihydrate
0.1pH

9.1* Formate 2.1% by weight, acetate 2.6% by weight or propionate 3.
Corresponds to 0%.

The liquid formulation was prepared according to the method disclosed in EP-A-346 995. The peptizing polymer corresponds to polymer A11 in the same specification.

Compositions D and E (structured liquid, containing peptizing polymer)

D E LA
S
23 23 Nonionic agent (7EO) 10
10 Sodium citrate
16.5 1
1.5 triethanolamine
− − Sodium carbonate
− −Sodium propionate
-5
protease
0.38 0.38 Peptizing polymer
1 1 Water and trace components

- Make it 100% - pH
8
．． 5 8.5 Liquid preparations are EP-A-3
46 995. The peptizing polymer corresponds to polymer A11 in the same specification.

Compositions F, G and H (structured liquid, containing peptizing polymer)

F G H L
A.S.
28 28 28 Nonionic agent (7EO) 12
12 12 Sodium citrate
10 10
10 triethanolamine
4 4 Sodium propionate - 5
-Sodium acetate
- - 7.
7 protease
0.38 0.38 0.38 Peptizing polymer
1 1 1 Water and trace components - 100
% - pH
9.3 9.3
9.3 Liquid preparations EP-A-346 99
It was prepared according to the method disclosed in No. 5. The peptizing polymer corresponds to polymer A11 in the same specification.

Compositions K and L (structured liquid, containing peptizing polymer)

K L LA
S
28 28 Nonionic agent (7EO) 12
12 Sodium citrate
8
8 Sodium carbonate
4 Sodium 4-propionate -
5 protease
0.38
0.38 Peptizing polymer
1 1
Water and trace ingredients
- Make it 100% - pH

9.2 9.2 The liquid formulation was prepared according to the method disclosed in EP-A-346 995. The peptizing polymer is polymer A11 in the same specification.
corresponds to

Composition M (structured, builder-containing liquid)
Ingredients
Weight LAS

6.7 Non-ionic agents (average 5E
O)
4.8 Sodium xylene sulfonate
0.2 Builder

20.0 Alkali metal salts

6.5 Protease

0.3 Trace ingredients + water
10
Carboxylic acid stabilizer to 0%
0.52 molar concentration*) Calcium chloride dihydrate
0.15pH

8.5*)
Compatible with 5% by weight of propionate Composition N (structured, phosphate builder-containing liquid) LAS

9.0 Non-ionic agent (7EO)
2.25 Pentasodium triphosphate

27.0 Sodium hydroxide
1.
1 Enzyme preparation
0.5 water
Balance Amount The pH of the composition was adjusted to 9.0. The composition is E
Prepared by PA-266 No. 199 (Unilever).

Example 1 Equimolar % of formate, acetate and propionate (ie 0
．． 31 molar concentration) was added to the composition A and compared, the following stability results were obtained.

Added carboxylate salt stability t1
/2 (Number of days) None
5 formate

20 Acetate
23 propionate
The stability of the 31 protease was determined by measuring protease activity (by spectrophotometry using a tetrapeptide substrate) as a function of storage time at 37°C. Half-life was determined by plotting Ao /At against time and performing non-linear regression analysis.

As a result of these, higher than 8.5
S in a builder-containing (built-in) anionic active agent-rich detergent composition, preferably having a pH greater than 9.0.
The half-life of avinase was superior when using propionate compared to using either formate or acetate. This result was surprising given the conventional wisdom in the art that stability data are superior for formate and acetate stabilizers compared to propionate. It is clear from the above that different results are obtained with specifically defined compositions of the invention (builder-containing compositions with a specific pH range and enriched with anionic agents).

Example 2 Equimolar % of formate, acetate and propionate (ie 0
．． 31 mol) was added to the structured compositions B and C described above and the following results were observed.

Composition B
Remaining added carboxylic acid salt after 215 hours Protease Protease activity % Improvement % None
Savinase
44
- formate
Savinase
66
52 Acetate Sa
vinase 69
58 Propionate Savina
se81
85

Remaining added carboxylic acid salt after 215 hours
Protease Protease activity%
No improvement %
BPN' 17
- Formate BPN'
27
58 Acetate
BPN'
28 6
3 Propionate BPN
' 44
155 Composition C
Remaining added carboxylic acid salt after 215 hours Protease Protease activity % Improvement % None
BPN'
38
- formate
BPN'
49 27
Acetate B
PN' 48
24 Propionate BPN'
59
55 These results demonstrate that propionate provides a significant improvement in protease stability over time in compositions rich in structured anionic actives at specific pHs. These results are unexpected in view of the teachings of the prior art.

Example 3 Equimolar % of formate, acetate and propionate at pH
A composition essentially the same as Structured Composition B was tested, except that the range was changed. The following results were observed.

Composition B at pH 8.0
Remaining added carboxylate protease after approximately 195 hours
Protease activity % Improvement % None
BPN'
23
- formate
BPN'
36 55
acetate
BPN' 36
55 Propionate BPN'
51
Composition B at 118 pH 8.6
Remaining added carboxylate protease after approximately 195 hours
Protease activity % Improvement % None
BPN'
21
- formate
BPN'
30 41
acetate
BPN' 31
47 Propionate BPN'
41
94 pH 9.0 Composition B
Remaining added carboxylate protease after approximately 195 hours
Protease activity % Improvement % None
BPN'
17
- formate
BPN'
27 61
acetate
BPN' 28
64 Propionate BPN'
38
125 As can be clearly seen from the above results, an unexpected increase in stability was observed over various pH ranges using propionate stabilizers versus formate or acetate stabilizers. Ta.

Example 4 Savinase stability was determined for compositions D and E. Savinase (manufactured by NOVO-Nordisk)
was added as either a liquid thickener or a liquid non-ionic activator slurry. Both formulations contain 16KNPU/g (KN
It has a proteolytic activity of PU = kiloNOVO protease units). Stability as half-life of activity at 37°C (days)
It was expressed as

Composition Stabilizer
Savinase liquid Savina
se slurry D None 2.1
25 E
Propionate 4.5
>>30 Example 5 Savinase stability was determined for compositions F, G and H. Savinase (NOVO-Nordisk
) was added as either a liquid thickener or a liquid non-ionic activator slurry. 16KNPU/g for both formulations
(KNPU = kiloNOVO protease unit) proteolytic activity. Stability is defined as half-life of activity at 37°C (
(number of weeks).

Composition Stabilizer
Savinase liquid Savina
se slurry F None 0.3
1 G
Acetate 0.6
nd H
Propionate 1
．． 6 4 (n
d=not measured) Example 6 The stability of Savinase was measured for compositions K and L. Savinase (manufactured by NOVO-Nordisk)
was added as either a liquid thickener or a liquid non-ionic activator slurry. Both formulations contain 16KNPU/g (K
It has a proteolytic activity of NPU = kiloNOVO protease units). Stability was expressed as half-life of activity (in weeks) at 37°C.

Composition Stabilizer
Savinase liquid Savina
se slurry K None 0.5
3 L
Propionate 0.8
7 Example 7 Savinase stability was determined with Composition M. Sa
Vinase (manufactured by NOVO-Nordisk) was added as either a liquid thickener or a liquid nonionic activator slurry. Both formulations contain 16KNPU/g (KNPU
= Klo NOVO protease units) proteolytic activity. Stability was expressed as half-life of activity (in weeks) at 37°C.

Composition Stabilizer
Savinase liquid Savina
se slurry M None 0.5
1.5M
Propionate 15
20 Example 8 Savinase stability was measured with Composition N. Sa
Vinase (manufactured by NOVO-Nordisk) was added as either a liquid thickener or a liquid nonionic activator slurry. Both formulations have proteolytic activity of 16 KNPU/g. Stability was expressed as the half-life of activity (in days) at 37°C.

[0076]

Claims (8)

[Claims] 1. (a) about 5 to about 65% by weight surfactant, (b) about 0.5 to about 50% by weight builder, (c
) an amount of added protease enzyme sufficient to have an activity level of 0.01 to 200,000 GU/g;
．． 1 to about 15% by weight of propionic acid or a propionate salt capable of forming propionic acid, the balance being water and minor ingredients, wherein the pH of the composition is greater than 7.0. Composition. 2. The composition of claim 1, wherein the surfactant is an anionic surfactant. 3. The surfactant is a mixture of an anionic surfactant and one or more detergent actives, wherein the weight ratio of anionic surfactant to non-anionic surfactant is greater than 1:1. A composition according to claim 1. 4. When the composition is structured, 5 to
Composition according to claims 1 to 3, using 35% by weight of builder. 5. If the composition is unstructured, 3
Compositions according to claims 1 to 3, using ~10% by weight of builder. 6. The stable aqueous enzymatic detergent composition of claims 1-4 further comprising about 0.1 to about 5% peptizing polymer. 7. The stable aqueous enzyme-based detergent composition of claims 1-6 further comprising about 0.01 to about 1% calcium salt. 8. The proteolytic enzyme is added in the form of a slurry of the enzyme in a liquid non-ionic surfactant.
7. The method for producing an aqueous liquid enzyme-based detergent composition according to 7.