BE1000341A3 - Aqueous compositions containing stabilized enzyme system for washing dishes, and methods of use thereof. - Google Patents

Abstract

Reinforced aqueous liquid composition containing a stabilized enzyme system, for washing dishes. The stabilized enzyme system contains a boron compound, an alpha-hydroxy carboxylic acid, casein and an enzyme. This system is used in the composition to communicate to it an effective proteolytic and amylolytic enzymatic cleaning activity. The composition contains adjuvant mineral detergency salts and other functional mineral salts, the stabilized enzyme system, a detergent and a metal salt of fatty acid as a physical stabilizing agent. With a view to its use for automatic dishwashing, the composition can be endowed with thixotropic properties by the addition of a thixotropic clay thickener. Field of application: household products for washing dishes.

Description

       

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    AQUEOUS COMPOSITIONS CONTAINING A
STABILIZED ENZYME SYSTEM FOR THE
DISHWASHING, AND THEIR DISHES
METHODS OF USE
French patent application 87. 14943 filed on October 28, 1987 by the Applicant describes a reinforced aqueous liquid detergent composition for washing laundry containing an enzyme stabilizing system comprising a boron compound, an alpha-hydroxy-carboxylic acid, casein and an enzyme.



   French patent application 87, 12321 filed on September 4, 1987 by the Applicant describes an aqueous thixotropic clay composition for washing dishes, containing aluminum stearate as a physical stabilizing agent.



   The present invention relates to reinforced aqueous compositions containing a stabilized enzyme system for washing dishes. The stabilized enzyme system contains a boron compound, an alpha-hydroxy carboxylic acid, casein and an enzyme. The present invention relates, in particular, to aqueous thixotropic clay liquid compositions for dishwashing, containing a stabilized enzyme system which comprises a boron compound, for example sodium borax, an alpha-hydroxy-carboxylic acid. , for example lactic, tartaric or citric acid, casein and an enzyme, for example proteolytic and amylolytic enzymes.

   The present invention relates more particularly to detergent compositions containing an enzyme stabilized system for. automatic washing of dishes, the enzyme of which is stable, which are physically stable and which are easy to disperse in a washing medium for effective cleaning of dishes, glassware,

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 porcelain, etc.



   Powdered detergent compositions and reinforced aqueous detergent compositions, including thixotropic compositions for dishwashing which are currently available do not contain stabilized enzyme systems.



   The present invention relates to reinforced aqueous liquid detergent compositions containing an enzyme for dishwashing, which are suitable for cleaning dishes, glassware, porcelain, utensils, etc. More particularly, the invention relates to detergent compositions, aqueous liquids containing an enzyme for washing dishes, which contain one or more detergency builders and which are characterized by their stability.



   The compositions for automatic dishwashing, also hereinafter referred to as DLAV, generally contain: (1) sodium tripolyphosphate (NaTPP) to soften hard water or retain the minerals it contains and to emulsify and / or "peptize" the dirt; (2) sodium silicate to provide the alkalinity necessary for effective detergent action and to provide protection for the enamels and patterns of fine porcelain;

   (3) sodium carbonate, generally considered optional, to increase alkalinity; (4) a chlorine-releasing agent to facilitate the removal of small soiling stains which lead to the formation of water stains and to facilitate the removal of staining stains such as tea and coffee; and (5) an anti-foam / surfactant combination for

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 provide the necessary detergent activity and reduce the foam, thereby increasing the efficiency of the machine.



  See, for example, SDA Detergents in Depth, "Formulations Aspects of Machine Dishwashing", Thomas Oberle (1974). The cleaning products which approach the compositions described above are for the most part liquids or powders.



   The use of a chlorine-releasing agent in certain dishwashing compositions has, however, been subject to criticism, as this agent tends to react with other chemically active ingredients, in particular the surfactant (see US Pat. No. 4,115,308) , thereby degrading the agent. thixotropy or suspension. and reducing its effectiveness. A feature of the present invention is that a chlorine releasing agent is not required in the composition for dishwashing.



   The formulation of liquid dishwashing compositions containing a stabilized enzyme is a difficult problem. The interest in incorporating enzymes into detergent compositions for dishwashing stems mainly from the effectiveness of proteolytic and amylolytic enzymes in the breakdown of protein and starchy substances found on dishes and dirty utensils, so that is facilitated the elimination of the residual food substances consumed such as meat sauce, eggs, tomato sauce, chocolate and others, during the washing of the dishes in an automatic machine.

   However, the enzyme substances which are suitable for dishwashing compositions, especially the proteolytic enzymes, are relatively expensive. In addition, it is known

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 that enzymes are unstable in reinforced aqueous detergent compositions for washing lin-
 EMI4.1
 ge.



   In the case of liquid laundry detergent compositions reinforced with a phosphate-type detergency builder, it is known that the problem of enzyme instability is particularly acute. The main cause is that phosphate-type detergency builders have a stabilizing effect on enzymes.

   In addition, the incorporation of a phosphate-type detergency builder into a liquid detergent composition for dishwashing poses an additional problem, namely, the possibility of forming a stable, single-phase composition; the solubility of sorting? Sodium phosphate, for example, being relatively limited in aqueous compositions, and very particularly in the presence of anionic detergents.



   Stabilization of enzymes in strongly alkaline detergent compositions is also difficult since it is known that the high alkalinity deactivates enzymes. Although it is possible to lower the pH to improve the stability of the enzymes, this to some extent cancels out the favorable effect of the adjuvants. The stabilized enzyme system of the present invention provides stability. of the enzyme even at relatively high pH, up to pH 10-12.

   Higher pHs, for example pH 10-12, are known to give better detergency and are preferred. A reduction in the pH of the detergent composition, for example to pH 7.5-9.5, can increase the stability of the enzyme, but shortens the life of the bubble bath and the beneficial effects of the detergency builder. that is to say detergent action.

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   US Patent No. 4,431,559 discloses a thixotropic composition for automatic dishwashing, comprising an aqueous solvent, a thickening agent, a source of chlorine, an anionic surfactant, adjuvant detergency salts and a buffer system for stabilize the chlorine source.



   US Patent No. 3,558,498 discloses a granular laundry detergent composition containing stabilized enzymes, sodium perborate trihydrate, anhydrous trisodium phosphate, anhydrous calcium sulfate and soluble or dispersible colors having a molecular weight of 5,000 to 1,000,000, for example casein having a molecular weight of 50,000 to 200,000.



   US Patent No. 3,560,392 discloses a granular laundry detergent composition containing an organic detergent, an alkaline detergency builder salt, a stabilized enzyme and a stabilizing amount of protein collagen having a molecular weight of 5 000 to 250,000.



   U.S. Patent No. 4,238,345 discloses a liquid laundry detergent composition in which the enzyme is stabilized by the addition of an antioxidant and a hydrophilic polyol having 2 to 6 hydroxyl groups. The patentee states in column 1 that calcium salts associated with proteins and glycerol associated with proteins have been used to form stabilizing enzyme systems in aqueous liquid laundry detergents.



   Patent application GB-A-2 079 305 discloses a reinforced aqueous liquid detergent composition containing an enzyme for washing clothes, in which the enzyme is stabilized by a mixture of a polyol and boric acid.

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   The present invention relates to an aqueous liquid composition reinforced with a polyphosphate for washing dishes, containing a stabilized enzyme system which comprises a boron compound, an alpha-hydroxy-carboxylic acid, a protic material, for example casein, and an enzyme.



   The stabilization of the enzyme is carried out by mixing beforehand a mixture of boron compound and alpha-hydroxy-carboxylic acid with a mixture of enzyme and casein in order to block the catate-
 EMI6.1
 Lytics of the enzyme with casdine and, simultaneously, blocking the structure of the enzyme with the mixture of boron compound and alpha-hydroxy carboxylic acid.



   In addition to ensuring very good stabilization of the proteases, the enzyme stabilizing system of the present invention exerts a very good stabilization of the amylases, which allows the use of double stabilized systems based on protease and amylase in very alkaline detergent compositions.



   The effective stabilization of amylase activity is surprising since one should expect that any amylase activator will be destroyed at pH
 EMI6.2
 less than 9.



   According to the present invention, machine washing of soiled dishes and utensils is accomplished by bringing the dishes and utensils into contact with a very powerful reinforced aqueous liquid composition for dishwashing, containing the stabilized enzyme system.



   The aqueous liquid dishwashing compositions of the present invention are capable of satisfactorily cleaning dishes and utensils containing both oily and particulate food soiling. Moreover, the

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 described compositions can be used for the pre-soaking of very dirty dishes which must be washed in an automatic dishwasher.



   The present invention is based on the discovery that a stabilized enzyme system comprising a boron compound, an alpha-hydroxycarboxylic acid, a proteinaceous substance, e.g. casein, and an enzyme, exerts a strong and potent stabilizing effect on enzyme in aqueous liquid compositions for washing dishes.



   In one embodiment, the present invention relates to an aqueous liquid dishwashing composition comprising an enzyme stabilizing system and a suspension of a phosphate-type adjuvant adjunct salt in the aqueous surfactant-based liquid detergent anionic.



   In another embodiment, the present invention relates to a thixotropic aqueous liquid clay composition for dishwashing, comprising an enzyme stabilizing system and a suspension of a phosphate-type detergency builder salt in the detergent aqueous liquid based on anionic surfactant.



   The Applicant has discovered that an enzyme stabilizing system consisting of a boron compound, an alpha-hydroxy carboxylic acid, a protein substance, for example casein, and an enzyme, exerts an activity. effective enzyme stable for relatively long periods of time in aqueous liquid dishwashing compositions.



   The dishwashing compositions of the present invention are physically stable. The aqueous liquid detergent composition of the present invention is easy to pour, easy to dose and easy to use.

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 put it in an automatic dishwasher.



       It would be interesting to have an aqueous liquid composition, possibly thixotropic with clay, for washing the vessel, which contains a stabilized enzyme system and possibly a physical stabilizing agent.



   It is therefore an object of the present invention to provide an aqueous liquid dishwashing composition containing a stabilized enzyme system.



   Another object of the invention is to provide a thixotropic aqueous liquid clay composition for dishwashing, containing a stabilized enzyme system.



   Yet another object of the invention is to provide a stabilized enzyme system containing a boron compound, an alpha-hydroxy carboxylic acid, casein and an enzyme, intended to be added to aqueous liquid compositions, possibly thixotropic, for washing dishes, in order to impart to said compositions an effective enzymatic cleaning activist of the proteolytic and / or amylolytic type.



   Yet another object of the invention is to improve the physical stability of aqueous thixotropic gel liquid compositions for dishwashing containing enzyme stabilized systems, by incorporating into a thixotropic clay composition for the dishwashing, a small effective amount of a metal salt of fatty acid, as a stabilizing agent, for example aluminum sterate, to inhibit sedimentation of suspended particles and prevent separation of phases.



   These and other objects of the invention

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 On reading the detailed description of the invention and its preferred embodiments, it will become more apparent from the description of the invention and is achieved by incorporating a stabilized enzyme system in an aqueous thixotropic composition, for example normally in the gel state. In order to improve the physical stability of the dishwashing composition, there may be included a small effective amount of a physical stabilizing agent, for example a fatty acid or a metal salt of fatty acid.

   More particularly, according to a preferred embodiment of the invention, there is provided a composition, normally in the gel state, for dishwashing, in which are incorporated a stabilized enzyme system containing a boron compound, a alpha hydroxy carboxylic acid, casein and an enzyme, and a stabilizing amount of a long chain fatty acid metal salt which is effective in inhibiting sedimentation of suspended particles.



   The present invention relates to an aqueous liquid phosphate-reinforced liquid composition for dishwashing, containing a relatively simple stabilized enzyme system which comprises a boron compound, an alpha-hydroxy carboxylic acid, a proteinaceous substance, for example casein. , and an enzyme. The enzyme stabilizer system stabilizes the active enzyme ingredient for relatively long periods of time, so that small amounts of expensive enzymes can be used.



   The present invention relates to an aqueous liquid composition based on an anionic surfactant, reinforced with a phosphate, for washing dishes, containing a stabilized enzyme which can be used at high effective pHs of the order of 10-12.

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 The present invention also relates to a powerful and effective composition for washing the vals-
 EMI10.1
 saddle, which does not require the use of a chlorine compound.



   According to a preferred form of packaging of the present invention, there is provided an aqueous composition, normally in the gel state, for automatic washing of dishes, endowed with thixotropic properties, which comprises, on a weight basis: (a) 8 35% of tripolyphosphates of alkali metals; (b) 0 to 20%, for example 2.5 to 20%, of sodium silicate;
 EMI10.2
 (c) 0 to 9% of alkali metal carbonate (d) 0 to 5%, for example 0.1 to 5%, of a detersive action material dispersible in water; (e) a thixotropic clay thickening agent, in a sufficient proportion to provide the composition with a thixotropic index of 0 to 10.0, for example approximately 2.5 to 10 (f) 0.5 to 2.0 % boron compound;

   (g) 1.5 to 4.0% alpha-hydroxy carboxylic acid?
 EMI10.3
 (h) 1 to 4.0% cassine; (i) 0.5 to 2.0% enzyme; (j) 0 to 5% foam inhibitor; (k) 0 to 8% sodium hydroxide; (1) 0 to 2% of a metal salt of long chain fatty acid; and (m) the rest of the water.



   Also in connection with this aspect, the invention relates to a method for cleaning dishes in an automatic dishwasher with an aqueous washing bath containing an effective amount of the liquid detergent composition for automatic washing of

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 dishes (DLLAV) as described above. According to this aspect of the invention, the DLLAV composition can be easily poured into the dispensing cup of the automatic dishwasher and, in just a few seconds, thicken quickly to return to its normal state of gel or paste so as to hold firmly inside the dispensing cup until shear forces are applied to it again, as if under the effect of the water jet sent by the dishwasher.



     According to the present invention, the activity of the enzyme is stabilized for a long period of time, so that small quantities of the enzyme provide effective cleaning activity; enzymatic. The enzyme activator is stabilized by the addition of small effective amounts of a stabilized enzyme system comprising a boron compound, an alpha-hydroxy carboxylic acid, a proteinaceous substance, for example casein, and an enzyme. The stabilized enzyme system is used in anionic-type aqueous compositions reinforced with phosphates.
 EMI11.1
 



  Stabilized Enzyme System
The stabilized enzyme system is preferably prepared separately and then added to the dishwashing composition.



   The stabilized enzyme system is preferably prepared according to a three-step procedure described below,
1. A boron compound is added to an alpha-hydroxy-carboxylic acid or salt to obtain a first mixture.



   2. The proteinaceous substance, eg casein, is added to an aqueous alkaline solution and the enzyme is added to the aqueous alkaline solution to

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 get a second mixture.



   3. The mixture of boron campest and alpha-hydroxy carboxylic acid obtained in step 1 is then mixed with the mixture of protein and enzyme obtained in step 2 to obtain a premix which is the stabilized enzyme system of the present invention.



   The mixture from step 1 and the mixture from step 2 above can each be added separately to the dishwashing composition, but the best enzyme stabilization results are obtained by pre-mixing the - diapers of steps 1 and 2, then adding the premix obtained to the dishwashing composition -
 EMI12.1
 the.



     Although the Applicant does not wish to be bound by any theory as to how the stabilized enzyme system works, it is believed that the boron compound reacts with alpha-hydroxy-carboxylic acid or alpha-hydroxy-polycarboxylic acid to form a boric acid ester. The boric acid ester is supposed to react on the enzyme and block its structure in the active configuration, thereby protecting it from denaturation. The protic substance is believed to block the catalytic sites of the enzyme and thereby prevent indigestion of other enzyme molecules during product storage.



   The stabilized enzyme system comprises: - a boron compound, for example borax, in an amount of 0.4 to 2.5, preferably 0.75 to 2.0, and more preferably 0.9 to 1.2, parts by weight; - an alpha-hydroxy-carboxylic acid, in an amount of 1 to 5, preferably 1.5 to 4, 0 and better still 1, 8 to 3, 6, parts by weight; - a protein substance, for example case-

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 EMI13.1
 ine, in an amount of 1 to 6, 0, preferably 1 to 4, 0, for example from about 1.0 to 2.0, parts by weight; and an. enzyme in an amount of 0.5 to 3.0, preferably 0.5 to 2.0, and more preferably 0.5 to 1.0 parts by weight.



   The weight ratio of alpha-hydroxy-carboxylic acid to boron compound can be
 EMI13.2
 7: 1 to 1: 1, preferably from 4: 1 to 1: 1 and better still from 3: 1 to 2: 1.



   The weight ratio of the protein substance, for example casein, to the enzyme can be
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 from 8: 1 to 1: 1; preferably from 4: 1 to 1: 1 and better still from 4: 1 to 2: 1.



   A preferred stabilized enzyme system of the present invention comprises the following components in the amounts indicated.



   Parts by Weight
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 Borax (N2B407. 10H20) 0.75-2.0 Alpha-hydroxy-carboxylic acid 1.5-5.4 Casein 1.0! 4, 0 Enzyme 0.5 to 2.0 The Stabilized Enzyme System can be added to the dishwashing composition in an amount of 10-30 parts by weight of the Stabilized Enzyme System per 90-70 parts by weight of detergent composition, preferably 15 to 25 per
 EMI13.5
 parts by weight ds'stäna a mcmas staMIR -: p-ju) "ss5 to 75 tB! Js sn pcncts de acnpositijm detjetcne, and ndBux sTocce from 15 to 20 parts ss pcmdb de sBtsne a ewjm sta pow 85 to 80 parts by weight detergent composition.

   The Stabilized Enzyme System is added to the dishwashing detergent composition such that the weight percentages of the active ingredients in the enzyme system are

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 bilized in the detergent composition are equivalent to the parts by weight mentioned above of the active ingredients in the stabilized enzyme system.



   A detailed description of the stabilized enzyme system is presented in French patent application 67, 14943 cited above.



     The stabilized enzyme system of the present invention can be used in aqueous liquid compositions for dishwashing, in aqueous thixotropic liquid compositions for dishwashing and in granular or powdered compositions for dishwashing.



   The stabilized enzyme systems of the present invention are, in a preferred embodiment, added to aqueous thixotropic liquid compositions for dishwashing.



   Alpha-Hydroxy-Carboxylic Acids
The alpha-hydroxy carboxylic acids which can be used in the present invention are organic carboxylic acids having 3 to 8 carbon atoms, including 1 to 3 carboxylic acid groups, and 1 to 3 hydroxyl groups.



   Preferred carboxylic acids are alpha-hydroxy carboxylic acids having 3 to 6 carbon atoms, including 1 to 3 carboxylic acid groups, and 1 to 2 hydroxyl groups. Suitable alpha-hydroxy carboxylic acids include: malic acid (HOOCCHOHCH2COOH), tartaric acid (HOOCCHOHCHOHCOOH), lactic acid (HOOCCHOHCH3) and citric acid (HOOCCH2C (OH) COOHCH2COOH).



  Preferred alpha-hydroxy carboxylic acids are

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 tartaric, lactic and citric acids. Citric acid is most appreciated. The alpha-hydroxycarboxylic acids can be used as such or in the form of their alkali metal salts, such as the sodium or potassium salts.



    Compounds of Boron
The boron compounds which are used in the dishwashing compositions of the
 EMI15.1
 present invention are those which are soluble in water and which, being added water, form boric acid or an alkali metal salt of boric acid. Boron compounds which can be used include boric acid, boric oxide or an alkali metal borate. Suitable borates of alkali metals are sodium and potassium ortho-, pyro- and mdtaborates, polyborates and bo-
 EMI15.2
 rax (Na-B O-. lOHO). The preferred boron compounds are boric acid, sodium borate (Na3B03) and borax (Na2B407.lOH20).



   Enzymes
The enzymes to be incorporated into the dishwashing compositions of the present invention may be proteolytic or amylolytic enzymes or mixtures thereof. The proteolytic enzymes suitable in the present invention include various commercial preparations in the form of liquid, powder or. dough, which have been adapted for use in the compositions
 EMI15.3
 detergents.



   Although the incorporation of the enzyme into the composition is more convenient in liquid form, the enzymes in the form of paste have proved useful. Appropriate enzyme preparations in form

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 liquid me include "Alcalas" and "Esperase" sold by Novo Industries, Copenhagen, Denmark; "Maxatase" and "Maxacal" sold by Gist-Brocades, Delft, PaysBas; and "Optimase" sold by Miles Kali Chemie. Appropriate proteolytic enzymes include subtilisin, bromelain, papain, trypsin and pepsin. Suitable enzymes include a liquid protease and a liquid amylase. The enzymes are preferably used in the form of their solutions.



  A preferred enzyme is Esperase 8 L in the form of a solution. Suitable preparations of alpha-amylase in liquid form are those sold by Novo Industries and Gist-Brocades under the respective brand names "Termamyl" and "Maxamyl". A preferred enzyme is Termamyl 120 L. "Esperase" 8L is preferred for the present compositions because of its activity at high pH values which correspond to the reinforced detergent compositions. Another preferred enzyme is Esperase 8.0L due to its high activity at 600C and its low activity at temperature
 EMI16.1
 ambient.

   In addition, Esperase 8. ÖL is stable at eluted pH, which allows a higher pH in the final product and better detergent action.



   Protein Substance
One of the components of the enzyme stabilizing system of the present invention is a proteinaceous substance, for example casein. The protein substances are used in the form of their water-soluble alkali metal salts (for example sodium or potassium) and / or are dispersed in an aqueous medium to which the enzyme is added.



   Proteins which are soluble or dispersible in water are used herein in an amount effective to stabilize the enzymes. Examples of

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 proteins which are soluble or dispersible in water and which can be used here include casein (average molecular weight from 50,000 to 200,000); Wilson's Protein WSP-X-1000 (a solubilized collagen with an average molecular weight of about 10,000) and Wilson's Hydrolysate Cosmetic 50, both marketed by Wilson's Pharmaceutical & Chemical Company; and Collagen. Hydrolyzate Cosmetic 50, marketed by Maybrook, Inc.

   A preferred casein-type protein is sold under the trademark "Caseinate de Sodium" by Bridal (France) or Dena, A. G. (R. F. A.).



  Sodium Caseinate is a mixture of several caseins of different molecular weights. Proteins, for example casein, are normally available in the form of powders. Proteins such as casein have the structure of long chemical chains. In the powdered state, the chains are folded back on themselves and form hydrogen bonds which maintain the protein in a globular form. The disentangling or denaturation of the protein involves the breaking of these bonds to form a looser, less ordered structure. Proteins can be denatured by boiling water cooking and the use of acids, alkalis and various detergents.

   Detangled or denatured proteins are more easily digested by enzymes and thereby produce a better stabilizing effect, that is to say provide better stability to the enzyme.



  Denaturation makes the protein more effective as a stabilizer. The protein, for example casein, is used in an amount sufficient to achieve stabilization of the enzyme activity.



  CompositionDetergentforWashingDishes
In general, the effectiveness of the

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 aqueous thixotropic clay positions for dishwashing are related:
 EMI18.1
 (a) alkalinity, (b) solubility in the washing medium, and (c) inhibition of foam. It is preferred here that the pH of the DLLAV composition is at least about 9.5, more preferably about 10.5 to 12.5, and most preferably at least about 11.5.

   At relatively lower pH values, the dishwashing detergent is too viscous, that is, almost solid, and therefore does not readily fluidize under the forces of shearing at the intensities where it is generated in the distributor bucket under normal machine operating conditions. In a few words, the composition loses most, if not all, of its character
 EMI18.2
 thixotropic. The addition of NaOH is therefore often necessary to raise the pH to the above ranges, and to improve the flowability properties.

   The presence of carbonate is also often necessary here, as it acts as a buffer which helps maintain the desired level of pH. Excess carbonate should be avoided, however, as this could result in the formation of needle-like carbonate crystals, which would compromise the stability, thixotropy and / or detergency of the DLLAV product, as well as its ability to be distributed from, by example, of bottles in compressible tubes. The other function of caustic soda (NaOH) is to neutralize the foam inhibitor of the phosphoric or phosphonic acid ester type, if it is present.

   Typical proportions of NaOH and sodium carbonate in the DLLAV composition are respectively about 0.5 to 3 percent by weight and about 2 to 9 percent by weight, although it should be noted that alkalinity

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 sulphurizing can be provided by NaTPP and sodium silicate. The sodium silicate can be used in proportions of 0 to 20 percent by weight, preferably 2.5 to 20 percent by weight and more preferably 5 to 15 percent by weight.



   NaTPP is used in the composition. DLLAV in proportions of about 8 to 35 percent by weight, preferably about 20 to 30 percent by weight. The NaTPP can be anhydrous or hydrated, which includes the stable hexahydrate or the degree of hydration. 6 corresponds to about 18% by weight of water or more. In fact, having regard to the stability of the hexahydrate, the presence of a little hydrating water is very effective in that it is believed to serve to form germs of stable hexahydrate which accelerates hydration and solubilization of the remaining NaTPP particles. If only hexahydrate is used, the detergent may be too runny and have little, if any,
 EMI19.1
 tere thixotropic.

   Conversely, if only anhydrous NaTPP is used, the product may, in certain cases, be too thick and therefore inappropriate. Particularly preferred DLLAV compositions are obtained, for example, when using a weight ratio of NaTPP (anhydrous to hexahydrate) of 0.5: 1 to 2: 1, values around 1: 1 being especially preferred.



   Inhibition of foam is important for increasing the efficiency of the dishwasher and minimizing the destabilizing effects which may occur due to the presence of excess foam in the water during employment. The foam can be reduced sufficiently by a judicious choice of the type and / or the quantity of detersive material, this component being the main producer

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 of foam.

   The degree of foaming also depends somewhat on the hardness of the washing water contained in the machine, so that an adequate adjustment of the proportions of NaTPP, which exerts a water softening effect, can help to obtain the desired degree of inhibition of the foam.

   However, one can at best include a depressant or foam inhibitor in. cases where a low foaming DLLAV product is desired. Particularly effective foam inhibitors are the alkyl esters of phosphonic acids corresponding to the formula:
 EMI20.1
 supplied, for example, by BASF-Wyandotte (PCUK-PAE), and in particular the acidic alkyl esters of phosphoric acid corresponding to the formula:
 EMI20.2
 supplied, for example, by Hooker (SAP) and Knapsack (LPKn-158), where one or both of the R groups in each ester type can independently represent C12-C20 alkyl groups. It is possible to use mixtures of esters of the two types or mixtures of mono and diesters of the same type.

   A particularly preferred foam inhibitor is a mixture of mono and di acid phosphates (C16-C18 alkyls)

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 EMI21.1
 such as a 1.2: 1 mixture of monostearyl / distearyl acid phosphates (Knapsack). If used, typical proportions of foam inhibitor in the composition are 0.1 to 5 percent by weight, preferably about 0.1 to 0.5 percent by weight, the ratio of weight of the detergent component (d) at the foam inhibitor (j) generally being in the range of about 10: 1 to 1: 1 and preferably about 4: 1 to 1: 1. D Other defoamers which can be used include, for example, known silicones.



   Sodium silicate, which gives alkalinity and ensures the protection of hard surfaces, such as the enamels and patterns of fine porcelain, is used in the composition in a proportion ranging from about 2.5 3 20 percent by weight, preferably about 5 to 15 percent by weight. Sodium silicate is usually added
 EMI21.2
 in the form of an aqueous solution, the NaO ratio of which; SiO is preferably about 1: 2, 2 to 1: 2, 8.



  At this stage, it should be noted that most of the other components of the present composition, in particular, NaOH, the foam inhibitor and the thixotropy thickener, are also often added in the form of a dispersion or aqueous solution beforehand. prepared.



   The detergent materials useful here are water dispersible surfactants of the anionic organic compound, amine oxide, phosphide oxide types.
 EMI21.3
 ne, sulfoxide or betalne. Anionic surfactants are preferred. Surfactants, for example anionic surfactants, are used in proportions in the range of about 0.1. at 5%, preferably about 0.3 to 2.0%.

   Particularly preferred surfactants here are mono and / or di (alkyl

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 in Ca-C14) - (diphenyD-mono-oxide and / or linear or branched alkali metal disulfates, commercially available, for example under the names DOWFAX (Trade Mark) 3B-2 and DOWFAX 2A- 1. In In general, paraffinsulfonates tend to reduce, if not suppress, thixotropy and have been found to excessively increase viscosity causing serious problems with shear forces.

   In addition, the surfactant must be compatible with the other ingredients of the composition. Other suitable surfactants include alkyl sulfates, alkyl sulfonates and alkylarylsulfonates with a primary alkyl group, and alkyl sulfates with a secondary alkyl group. Examples are (C 10 -C 11 alkyl) sodium sulfates such as sodium dodecyl sulfate and (tallow alkyl) sodium sulfate; sodium (C10-C18 alkane) sodium sulfonates such as sodium hexadecyl-1 sulfonate; and sodium (C12-C18 alkyl) benzenesulfonates such as sodium do-decylbenzenesulfonates. The corresponding potassium salts can also be used.

   Examples of suitable alkyl sulfonates are sodium and potassium (primary alkyl C10-C18) sulfonates, sodium (normal primary C10-C15 alkyl) sulfonates being preferred.



   Like other suitable surfactants or detergents, amine oxide type surfactants typically have the structure R2R1N = O, in which each R represents a lower alkyl group, for example methyl, and R1 represents a long chain alkyl group having from 8 to 22 carbon atoms, for example a lauryl, myristyle, palmityl or cetyl group. Instead of an amine oxide, it is possible to use a surfactant of the corresponding type phosphine oxide R2R PO or sulfoxide RRSO. Betalne type surfactants

  <Desc / Clms Page number 23>

 typically have the structure RR1N-R'COO-, in which the R 'represents a lower alkylene group having 1 to 5 carbon atoms.

   Particular examples of these surfactants are lauryl dimethyl amine oxide, myristyl dimethyl amine oxide, corresponding phosphine oxides and sulfoxides, and corresponding cattle, including dodecyldimethyl acetate. ammonium, tetradecyl-diethyl-ammonium pentanoate, hexadecyl-dimethyl-ammonium hexanoate, etc. To ensure biodegradability, the alkyl groups of these surfactants must be linear, and from. such compounds are preferred.



   Surfactants of the above types, all well known in the art, are, for example, described in U.S. Patents NO 3,985,668 and 4,271,030.



   Thixotropic thickeners, i.e. thickeners or suspending agents which impart thixotropic properties to an aqueous medium, are known in the art and can be organic or mineral, water soluble, water dispersible or cooloidogenic, and monomers or polymers, and they must obviously be stable in these compositions, in particular with respect to the strong alkaliniter. Thixotropic thickeners which are particularly preferred generally include colloidogenic mineral clays of the smectite and / or attapulgite types. Organic clays can also be used as thixotropic thickeners.



  These materials have been used generally in proportions of about 1.5 to 10, preferably 2 to 5, percent by weight to impart the desired thixotropic properties and Bingham plasticity to the described DLLAV compositions. in the Applicant's previous applications GB-2 116 199A and -2 140 450A.

  <Desc / Clms Page number 24>

 
 EMI24.1
 



  In accordance with the present invention, proportions of the colloidogenic mineral clays of the smectite and / or attapulgit types comprised in the range of about 0.25 to 5%, preferably 0.50 to 4.0%, especially 1, 0 to 3% are generally sufficient to obtain the desired thixotropic properties and the Bingham plasticity character. Smaller amounts of the thixotropy agent can be used when used in conjunction with a metal salt of fatty acid serving as a physical stabilizing agent.



   Smectite clays include the various varieties of montmorillonite (bentonite), hectorite, attapulgite, smectite, saponite and others.



  Montmorillonites are preferred and are available under commercial brands such as Thixogel (Trademark Deposited) Void and Gelwhite (Trademark Deposited) GP, H, etc., from Georgia Kaolin Company; and ECCAGUM (Trademark Registered) GP, H, etc., at tuthern Clay Products. Attapulgites include the materials available under the trade name Attagel (Trade Mark), that is to say Attagel 40, Attagel 50 and Attagel 150, from Engelhard Minerals and Chemicals Corporation.



  Smectite and attapulgite mixtures in weight ratios of 4: 1 to 1: 5 are also useful here. The thickening or suspending agents of the preceding types are well known in the art and are for example described in the US patent No. 3,985,668 referred to above. Abrasives or polishing agents should be avoided in DLLAV compositions, as they can damage the surface of fine dishes, crystal, etc.



   The proportion of water contained in these compositions must obviously not be too high to the point

  <Desc / Clms Page number 25>

 to generate too low a viscosity and a too great fluidity, nor insufficient to the point of generating a too high viscosity and a too weak flowability, the thixotropic properties being in one or the other case diminished or destroyed . This proportion is readily determined by routine experimentation in any particular case, and is generally in the range of about 35 to 65 percent by weight, preferably about 40 to 55 percent by weight. It is also necessary to pre-
 EMI25.1
 requires that the water be deionized or softened.



   Unless otherwise indicated, the description of the DLLAV product generally conforms to that of the compositions described in patent applications GB-2 116 199A and 2 140 450A of the Applicant.



   The DLLAV products of the previous applications GB-2 166 199A and -2 140 450A have improved rheological properties, as evaluated in. determining the viscosity of the product as a function of the shear rate. These compositions exhibit a higher viscosity at a low shear rate and a lower viscosity at a high shear rate, the results indicating that effective fluidization and gelification occurs largely within the limits of the range of rate ratios. shear encountered in common automatic dishwashers.



  In practical terms, this results in better pouring and processing characteristics, as well as less leakage in the dispenser cup. machine, compared to liquid or gel DLAV products of the prior art. For shear rates corresponding to 3 to 30 rpm, the viscosities (Brookfield) ranged from about 10,000-30,000 mPa, respectively. s at about 3000-7000 mPa.s, as measured at room temperature using

  <Desc / Clms Page number 26>

 of a Brookfield LVT viscometer after 3 minutes using a No. 4 spindle. A shear rate of 7.4 s-1 corresponds to a spindle speed of approximately 3 rpm.

   An increase of about 10 times in the shear rate results in a reduction of about 3 to 9 times the viscosity. With prior art DLAV gals, the corresponding reduction in viscosity was only about 2-fold. In addition, with these compositions, the initial viscosity raised to about 3 rpm was only about 2,500 to 2,700 mPa. These compositions of the aforementioned previous applications thus manifest fluidization thresholds at lower shear rates and of a markedly greater magnitude in terms of incremental increase in the shear rate as a function of the incremental decrease in viscosity.

   This property of the DLLAV products of the above-mentioned earlier applications is summarized by a thixotropy index (IT) which is the ratio of the apparent viscosities at 3 rpm and 30 rpm. The compositions of these prior applications have an IT of 2 to 10. The tested DLLAV compositions exhibited a massive and rapid return to the consistency of the quiescent state upon cessation of the shear force.



   French patent application 87. 12321 mentioned above, is based on the discovery according to-
 EMI26.1
 which the physical stability, that is to say the resistance to phase separation, to sedimentation, etc., of the aqueous liquid DLAV compositions of patent applications GB-2 116 199A and -2 140 450A can be significantly improved , without adversely affecting and, in some cases, improving their rheological properties, by adding to these compositions a small but effective amount of a metal salt of a long chain fatty acid.

  <Desc / Clms Page number 27>

 



   As an example of improving the rheological properties, it has been found that the weak. shear rate, for example At a spindle speed of about 3 rpm, the apparent viscosities can
 EMI27.1
 often be increased 2 to 3 times by incorporating as little as 0.2% or less, for example 0.16%, of the metal salt of stabilizing fatty acid.

   At the same time, physical stability can be improved to such an extent that after a long period of time, twelve weeks or more, in temperature intervals extending from near-freezing to 400C or more, the compositions containing the metal salts of stabilizing fatty acids undergo no observable phase separation.



   The preferred long chain fatty acid metal salts are those presented in the above-mentioned application 87.12321. Metal salts of suitable fatty acids are the metal salts of higher aliphatic fatty acids having about 8 to about 22 carbon atoms, preferably about 10 to 20 carbon atoms, and with very particular preference about 12 to 18 carbon atoms, including the carbon atom of the carboxyl group of the acid
 EMI27.2
 bold. The aliphatic radical can be saturated or unsaturated and 11 can be straight or branched.

   Saturated straight chain fatty acids are preferred. Mixtures of fatty acids can be used, such as those from natural sources, such as tallow fatty acid, coconut fatty acid, soy fatty acid, etc., or from synthetic sources which are made available. industrial manufacturing processes.



   Thus, examples of the fatty acids from which the stabilizing metal salts can be prepared include, for example, deca- acid.

  <Desc / Clms Page number 28>

 noique, dodecanolque acid, palmitic acid, myristic acid, stearic acid, oleic acid, eicosanoic acid, tallow fatty acid, coconut fatty acid, fatty acid soy, mixtures of these acids, etc. Stearic acid and mixtures of fatty acids are preferred.



   Preferred metals are versatile minds such as magnesium, calcium, aluminum and zinc.



   Many of these metal salts are commercially available. For example, aluminum salts are available in the form of three acid residues, for example aluminum stearate in the form of aluminum tristearate Al (C17H35COO) 3. Salts with a single acid residue, for example aluminum monosterate Al (OH) 2 (C17H35COO), and salts with two acid residues, for example aluminum distere Al (OH) ( C17H35COO) 2, and mixtures of two or three salts with one, two and three acid residues, can be used for metals which, such as AI, have the valence +3, and mixtures of salts with one and two residue acid can be used for metals which, like Zn, have the valence +2.



   The polyvalent salts of fatty acids preferred as stabilizing agents are calcium sterate, that is to say calcium distearate, magnesium sterate, that is to say magnesium distearate, stearate aluminum, i.e. aluminum tristearate, and zinc stearate, i.e. di
 EMI28.1
 zinc stearate.



   Naturally, the use of fatty acids as stabilizing agents offers, because of their well known low toxicity, a particular advantage for the DLLAV compositions, as well as for all the other applications in which the composition of the invention

  <Desc / Clms Page number 29>

 tion or is likely to come into contact with objects used to handle, store or serve food products or is in any other way likely to come into contact with or be consumed by humans or animals. In this respect, calcium stearate, that is to say calcium distearate, and magnesium c stearate! that is, magnesium distearate, are particularly preferred because they are generally harmless food additives.



   The proportion of metal salts of stabilizing fatty acids suitable for obtaining the desired improvement in physical stability depends on factors such as the nature of the fatty acid salt, the nature and the proportion of the thixotropy agent, of the detersive compound. , mineral salts, especially TPP, and other ingredients of the DLLAV product, as well as the conditions provided for storage and transport.



   However, in general proportions of stabilizers of the metal salt type of fatty acid ranging from approximately 0.2 to 2%, preferably from approximately 0.5 to 1.0%, and with a very particular preference of about 0.5 to 0.8%, ensuring long-term stability and the absence of phase separation at rest or during transport at low and high temperatures, as required from a product acceptable from the point of view commercial.



   Depending on the proportions and types of physical stabilizers and thixotropic agents, the addition of the metal salt of fatty acid not only increases physical stability but also provides a simultaneous increase in apparent viscosity.



  Fatty acid to thixotropic agent ratios ranging from about 0.08 to 0.4 percent by weight of acid

  <Desc / Clms Page number 30>

 Fat for about 1.3 to 2.5 percent by weight of thixotropy agent is generally sufficient to provide these simultaneous benefits and, therefore, the greatest preference is given to the use of these ingredients in these reports.



   According to one of the processes for manufacturing these compositions, it is necessary to dissolve or disperse. first of all all the mineral salts, ie carbonate (slil is used), silicate and tripolyphosphate, in the aqueous medium. The thickening agent (if used) is added just before the stabilized enzyme system. The foam inhibitor
 EMI30.1
 (slil is used) is previously prepared in the form of an aqueous dispersion, as is the thickening agent. The foam inhibitor dispersion, caustic soda (if used) and the mineral salts are first mixed at elevated temperature to form an aqueous solution (deionized water), then cooled, with stirring. start to end of operation.

   The surfactant, the stabilizing fatty acid salt and the thickening agent dispersion are then added at room temperature to the cooled solution (20-25 C). The stabilized enzyme system of the present invention is added last.



   The total concentration of salts (NaTPP, sodium silicate and carbonate) is generally around 20 ä
50 percent by weight, preferably around 30 to
40 percent by weight, in the composition. The stabilized enzyme system generally constitutes from about 15 to 25 parts by weight, preferably 15 to 20 parts by weight, of the composition.



   Another method for mixing the ingredients of the DLLAV compositions is to form everything. first a mixture of water, foam inhibitor (if used), detergent,

  <Desc / Clms Page number 31>

 physical stabilization (if used), for example a fatty acid salt, and thixotropy agent (if used), for example a clay. These ingredients are mixed together under high shear conditions, preferably starting at room temperature, so as to obtain a uniform dispersion. The remaining ingredients are incorporated into this premix under low shear mixing conditions.

   For example, the required amount of premix is introduced into a low shear mixer, then the remaining ingredients are added, while mixing, either successively or simultaneously. Preferably the ingredients are added successively, although it is not essential to complete the addition of a given ingredient in its entirety before starting to add the next ingredient. In addition, one or more of the ingredients can be divided into several portions and added at different times.

   Good results have been obtained by adding the remaining ingredients in the following order: sodium hydroxide, alkali metal carbonate, sodium silicate, alkali metal tripolyphosphate (hydrate), alkali metal tripolyphosphate (anhydrous or containing at most 5% water), sodium hydroxide and finally stabilized enzyme system.



   Other conventional ingredients may be included in these compositions in small proportions, generally less than about 3 percent by weight, for example a perfume, hydrotropic agents
 EMI31.1
 such as benzene-, tolubne-, xylene-, and sodium cumenesulfonates, preservatives, dyestuffs and pigments, etc., all of which are obviously stable with respect to high alkalinity (property common to all components). Subjects

  <Desc / Clms Page number 32>

 dyes particularly referred are chlorinated phtÅalocyanines and aluminosilicate polysulphides which communicate respectively pleasant green and blue hues. TiO2 can be used to whiten or neutralize degraded shades.



   The liquid DLAV compositions of the present invention are used extensively. known for washing dishes, kitchen utensils, etc., in an automatic dishwasher equipped with a suitable detergent dispenser, in an aqueous washing bath containing an effective amount of the composition.



   Although the invention has been described in particular in terms of its application to aqueous thixotropic clay detergents for automatic washing of dishes, those skilled in the art will readily appreciate that the advantages obtained by the addition of the stabilized enzyme system apply equally to aqueous liquid compositions and powdered compositions for washing dishes.



   The invention can be practiced in various ways and a certain number of particular embodiments will be described for illustrative purposes in the following examples where all the quantities and proportions are expressed by weight relative to the weight of the composition , unless otherwise stated.



   EXAMPLE 1
A stabilized enzyme system is prepared in accordance with the present invention by the following procedure. fl) 12.6 grams of sodium borate are added
 EMI32.1
 (Na3 bo3) at 56, 1 grams of tartaric acid in 90 grams of water, while stirring. We neutralize the food

  <Desc / Clms Page number 33>

 diaper up to about 7 with 56.1 grams of NaOH (50% solution).



   (2) 60 grams of casein, supplied by Bridel, are added to 270 grams of water containing 1.8 grams of NaOH, while stirring and heating. After complete dissolution, 15 grams of Esperase 8.OL are added at 500C and 9 grams of Termamyl 120L are added at room temperature to obtain a casein-enzyme mixture.



   (3) The mixtures obtained in steps (1) and (2) above are mixed together to obtain the premixed stabilized enzyme system of the present invention.



   The entire premix stabilized enzyme system, i.e., about 570.6 grams, can be incorporated into an aqueous liquid dishwashing composition or in a container.
 EMI33.1
 liquid composition that see thixotropea clay p. for dishwashing, about 3,000 g of dishwashing composition is obtained in which the components of the stabilized enzyme system of the present invention are present in the above proportions.
 EMI33.2
 
 <tb>
 <tb>



  For <SEP> Hundred <SEP> in <SEP> Weight
 <tb> Na3Bo3 <SEP> 0.4
 <tb> Acid <SEP> tartaric <SEP> 1, <SEP> 9
 <tb> Casein <SEP> 2, <SEP> 0
 <tb> Esperase <SEP> 8. <SEP> 0L <SEP> 0, <SEP> 5
 <tb> Termamyl <SEP> 120L <SEP> 0, <SEP> 3
 <tb>
 
The dishwashing compositions which contain the stabilized enzyme system of the present invention are found to be effective in cleaning

  <Desc / Clms Page number 34>

 
 EMI34.1
 dirty dishes, even in the absence of compounds providing active chlorine.



   EXAMPLE 2; According to the procedure of Example 1, a stabilized enzyme system containing the following ingredients is prepared.
 EMI34.2
 
 <tb>
 <tb> stuffed <SEP> in <SEP> fOlds
 <tb> Na2B407 <SEP> lOH20 <SEP> 0, <SEP> 8
 <tb> Acid Citric <SEP> <SEP> 2.6
 <tb> Casdine <SEP> 2, <SEP> 0
 <tb> Esperase <SEP> 8. <SEP> OL <SEP> 0.5
 <tb> Termamyl <SEP> 120L <SEP> 0.3
 <tb>
 
A thixotropic clay detergent composition is prepared for dishwashing, and about 19 parts by weight of the above stabilized enzyme system is added to about 81 parts by weight of the detergent composition to obtain the detergent composition for washing of the following dishes.
 EMI34.3
 
 <tb>
 <tb>



  For <SEP> Hundred <SEP> in <SEP> Weight
 <tb> Water Deionized <SEP> <SEP> 43, <SEP> 7
 <tb> Solution <SEP> from <SEP> soda Caustic <SEP>
 <tb> (50 <SEP>% <SEP> from <SEP> NaOH) <SEP> 2.2
 <tb> Carbonate <SEP> from <SEP> sodium <SEP> (anhydrous) <SEP> 5, <SEP> 0
 <tb> Silicate <SEP> from <SEP> sodium <SEP> (solution
 <tb> to <SEP> 47, <SEP> 5 <SEP>% <SEP> due <SEP> report <SEP> Na2O: SiO2 <SEP> =
 <tb> 1 <SEP>:

    <SEP> 2, <SEP> 4) <SEP> 15, <SEP> 74
 <tb> TPP <SEP> from <SEP> sodium <SEP> (substantially <SEP> anhydrous, <SEP> that is to say <SEP> 0-5 <SEP>%, <SEP> from
 <tb> preference <SEP> 3 <SEP>% <SEP> humidity)
 <tb> (Thermphos <SEP> NW) <SEP> 12, <SEP> 0
 <tb> TPP <SEP> from <SEP> sodium <SEP> (hexahydrate)
 <tb> (Thermphos <SEP> N <SEP> hex) <SEP> 12, <SEP> 0
 <tb> Na2B4O7.10H2O <SEP> 8
 <tb>
 

  <Desc / Clms Page number 35>

 
 EMI35.1
 
 <tb>
 <tb> Acid Citric <SEP> <SEP> 2.6
 <tb> Casein <SEP> 2, <SEP> 0
 <tb> Esperase <SEP> 8.

    <SEP> OL <SEP> 0, <SEP> 5
 <tb> Termamyl <SEP> 120L <SEP> 0, <SEP> 3
 <tb> Phosphate <SEP> from <SEP> monostearyl <SEP> 0, <SEP> 16
 <tb> DOWFAX <SEP> 3B-2 <SEP> (solution <SEP> aqueous <SEP> to
 <tb> 45 <SEP>% <SEP> from <SEP> monod6cyl / didecyl- <SEP> (oxide
 <tb> of <SEP> diphenyl) <SEP> disulfonate <SEP> from <SEP> Na) <SEP> 0.80
 <tb> Stearate <SEP> of aluminum <SEP> 0, <SEP> 20
 <tb> Pharmagel <SEP> H <SEP> (Clay <SEP> thixotropic) <SEP> 2. <SEP> cl
 <tb> 100.00
 <tb>
 
EXAMPLE 3
The thixotropic aqueous liquid composition for washing the dishes of Example 2 containing the system was tested. <The stabilized enzyme of the present invention comprising 0.5 percent by weight of Esperase 8.

   0L and 0.3 percent by weight of Termamyl 120L, to determine the proteolytic activity and the amylolytic activity after aging at 4 ° C., at room temperature and at 350 ° C. for 1, 4 and 8 weeks. The dishwashing detergent composition had a pH of about 11.7. The results obtained are reported in the following table.
 EMI35.2
 
 <tb>
 <tb>



  Temperature <SEP> from <SEP> aging <SEP> Temperature
 <tb> Time <SEP> from <SEP> aging <SEP> 40C <SEP> ambient <SEP> 350C
 <tb> (weeks) <SEP> 1 <SEP> 2 <SEP> 4 <SEP> 1 <SEP> 2 <SEP> 4 <SEP> 1 <SEP> 2 <SEP> 4
 <tb> -------------------------------------------- Activity <SEP> proteolytic <SEP> 77 <SEP> - <SEP> 58 <SEP> - <SEP> - <SEP> 51 <SEP> 38 <SEP> - <SEP> 32
 <tb> Activity <SEP> amylolytic <SEP> - <SEP> 50 <SEP> - <SEP> - <SEP> 22 <SEP> - <SEP> - <SEP> 4 <SEP> -
 <tb>
 
The stabilized enzyme system of the present invention, consisting of borax-citric acid and

  <Desc / Clms Page number 36>

 caseine-Esperase and Termamyl, not only allows stabilization of the amylase under very unfavorable conditions (the amylase is normally destroyed at pH 9)

   but also allows an amylolytic activity observed at very alkaline pH. In fact, the dishwashing detergent composition exhibited amylolytic activity after 5 months of storage at room temperature.



   By other tests, it was found that the efficacy of the above composition on hard residues was greater than that of any commercially available DLAV product, in particular at a low concentration of 5 9/1 in the dish-washer.



   EXAMPLE 4
 EMI36.1
 In accordance with the present invention, an aqueous liquid detergent composition is prepared which is suitable for manual washing of dishes and for pre-soaking, especially very dirty dishes, before machine washing. This composition contains the following ingredients in the indicated proportions.
 EMI36.2
 
 <tb>
 <tb>



  For <SEP> Hundred <SEP> in <SEP> Weight
 <tb> Water <SEP> dasionisde <SEP> 46, <SEP> 1
 <tb> Solution <SEP> from <SEP> soda Caustic <SEP>
 <tb> (50 <SEP>% <SEP> from <SEP> NaOH) <SEP> 2, <SEP> 2
 <tb> Carbonate <SEP> from <SEP> sodium <SEP> (anhydrous) <SEP> 5, <SEP> 0
 <tb> Silicate <SEP> from <SEP> sodium <SEP> (solution <SEP> ä
 <tb> 47.5 <SEP>% <SEP> from <SEP> report <SEP> Na2O: SiO2 <SEP> =
 <tb> 1:

  2,4) <SEP> 15.74
 <tb> TPP <SEP> from <SEP> sodium <SEP> (Thermphos <SEP> Mi) <SEP> 12, <SEP> 0
 <tb> TPP <SEP> from <SEP> sodium <SEP> (Thennphos <SEP> N <SEP> hex) <SEP> 12, <SEP> 0
 <tb> Na2B4O6.10H2O <SEP> 0.9
 <tb> Acid <SEP> lactic <SEP> 1, <SEP> 8
 <tb> Casein <SEP> 2, <SEP> 0
 <tb>
 

  <Desc / Clms Page number 37>

 
 EMI37.1
 
 <tb>
 <tb> Esperase <SEP> 8.

    <SEP> 0L <SEP> 0, <SEP> 8
 <tb> Phosphate <SEP> from <SEP> monostearyl <SEP> 0, <SEP> 16
 <tb> DOWFAX <SEP> 3B-2 <SEP> (solution <SEP> aqueous
 <tb> ä <SEP> 45 <SEP>% <SEP> from <SEP> monodecyl / didecyl-
 <tb> (oxide <SEP> from <SEP> diph6nyl) <SEP> disulfonate
 <tb> of <SEP> Na) <SEP> 0, <SEP> 80
 <tb> Stearate <SEP> of aluminum <SEP> 0, <SEP> 50
 <tb> 100, <SEP> 00
 <tb>
 
The detergent compositions containing a stabilized enzyme system for dishwashing of the present invention can also be formulated as powder compositions.



   In the above preparation procedure, those skilled in the art can vary the ingredients and their proportions in order to obtain detergent compositions for washing dishes whose ingredients and proportions are specific.


    

Claims (23)

 CLAIMS 1. Aqueous liquid composition for washing dishes, containing a stabilized enzyme system, comprising water, an alkali metal phosphate as detergency builder salt, an organic surfactant, a boron compound, a carboxylic acid, a protein substance and an enzyme.  2. Composition according to claim 1, characterized in that the boron compound is at least one of borax (Na2B4O7.1OH2O), sodium borate (Na3BO3), boric acid and boric oxide.  3. Composition according to claim 1, caracterisde in that the protein substance is la: casein. ; 4. Aqueous liquid composition for washing dishes containing a stabilized enzyme system, comprising, by weight: 35 to 65% water, 8 to 35% of alkali metal phosphate as detergency builder salt, 0 to 20% sodium silicate, 0 to 5% of an organic surfactant, 0.4 to 2% of a boron compound, 1 to 5 to a carboxylic acid, 1 to 6% of a protein substance and 1 to 6% enzyme.  5. Composition according to claim 4, characterized in that it comprises 0 5% by weight of a thixotropic clay thickening agent.  6. Composition according to claim 4, characterized in that the boron compound is at least one of borax '(Na2B407. LOH20), sodium borate (Na3BO3), boric acid and boric oxide , and in that the carboxylic acid is an alpha-hydroxy-carboxylic acid.  7. Composition according to claim 4, characterized in that it comprises, by weight: 40 to 55% of water, 20 to 30% of sodium tripolyphosphate, 0 to 5% of an organic surfactant, 0 to 20% of silica-  <Desc / Clms Page number 39>  sodium te, 0 to 9% sodium carbonate, 0 to 5% anti-foaming agent, 0.75 to 2.0% borax (Na2B407 '1020), 1.5 to 4.0% alpha acid -hydroxycarboxylic, 1.0 to 4.0% casein and 0.5-2.0% enzyme.  8. Composition according to claim 7, characterized in that the organic surfactant is a sodium (linear tridecyl) benzenesulfonate.  EMI39.1   9. Composition according to claim 7, characterized in that alpha-tyccoXBliqt acid. B is at least one of lactic acid, tartaric acid, citric acid and their sodium salts.  10. Composition according to claim 7, characterized in that the alpha-hydroxy-carboxylic acid is at least one of citric acid and its sodium salt.  11. Composition according to claim 4; characterized in that it comprises, by weight: 40 to 55, of water, 20 to 30% of sodium tripolyphosphate, 0.25 to 5.0, 0% of thixotropic clay thickening agent, 0.1 to 5% of anionic surfactant, 0 to 20% sodium silicate, 2 to 9% sodium carbonate, 0.1 to 0.5% anti-foaming agent, 0.75 3 2.0% borax (Na2B4O7.1OH2O), 1.5 3 4.0% alpha-hydroxycarboxylic acid, 1.0-4.0% casein and 0.5-2.0% enzyme.  12. Composition according to claim 11, characterized in that the anionic surfactant is linear sodium decylsulfonate.  13. Composition according to claim 11, characterized in that the alpha-hydroxy-carboxylic acid is at least one of lactic acid, tartaric acid, citric acid and their sodium salts.  14. A thixotropic aqueous composition for  <Desc / Clms Page number 40>  automatic washing of dishes containing a stable enzyme system, comprising, by weight: 40 to 55% water, 20 to 30% sodium tripolyphosphate, 0.5 to 4.0% thixotropic clay thickener, 2.5-20% sodium silicate, 2-9% sodium carbonate, 0.3-2.0% anionic surfactant, 0.75-2.0% borax (Na2B4O7.10H2O), 1.5 to 4.0% alpha-hydroxy carboxylic acid, 1.0 to 4.0% casein and 0.5 to 2.0% enzyme.  15. Composition according to claim 14, characterized in that it contains a metal salt of long-chain fatty acid as a physical stabilizing agent, in an amount sufficient to increase the cystic stability of the composition.  16. Composition according to claim 15, characterized in that the physical stabilizing agent is aluminum st6arate.  17. Composition according to claim'15, characterized in that the physical stabilizing agent is present in a proportion of 0.1 to 2% by weight.  18. Composition according to claim 14, characterized in that the thixotropic thickener is a mineral or organic colloldogenic clay.  19. Composition according to claim 18, characterized in that the clay is a montmorillonite, an attapulgite, a hectorite or a smectite.  20. Composition according to claim 14, characterized in that it contains 0.1 to 0.5% by weight of an anti-foaming agent.  21. A method for cleaning soiled dishes, characterized in that it consists in bringing soiled dishes in contact with the aqueous liquid composition for washing dishes of claim 1.  <Desc / Clms Page number 41>      -, 22. Method for cleaning soiled dishes in an automatic dishwasher, characterized in that it consists in bringing the soiled dishes in contact, in an automatic dishwasher, with an aqueous washing bath in which is dispersed an effective amount of the composition of claim 7.  23. Method for cleaning soiled dishes in an automatic dishwasher, characterized in that it consists in bringing the soiled dishes in contact, in an automatic dishwasher, with an aqueous washing bath in which an effective amount of the composition of claim 14.