LU87344A1 - THICK AQUEOUS DETERGENT COMPOSITION CONTAINING LITTLE OR NO PHOSPHATE AND DISHWASHING METHOD USING THE SAME - Google Patents

Description

88 / B 52 779

‘'1 Q 7 X L \ L · GRAND-DUCHY OF LUXEMBOURG

Patent N ° ......... M ...... / ........... Ύ ............_ ”*. , w. .

, , Minister

j 23 September 1988 wû. ,. J

of................................................. ............................................. · of the Economy and Average Classes Tîtrp. Hplivrp iSlŒ · Intellectual Property Service 1 st e vre -..................................... .............. LUXEMBOURG - Älif Invention Patent Application a, -oM. .................................................. .................................................. ............................. (1) I. Request

The company known as: COLGATE-PALMOLIVE COMPANY, 300 Park Avenue, NEW YORK, NY 10022 (United States of America), represented by Mr. Jacques de Muyser acting in ................ .quality of ...... agent ................................ ........ .................................................. ............ (3) deposits (ntj.ce twenty-three September 1900 eighty-eight at .................... ..................... hours, at the Ministry of the Economy and the Middle Classes, in Luxembourg: 1. this request for obtaining a patent of invention relating to: ................... "Thick aqueous detergent composition containing little ..... or (5) .......... ............. not ....... of ...... phosphate ...... and ...... method ...... of .dishwashing.............................................

....................... using it. "................................................. .................................................. .................................................. ...

2. description in language ......... Rariçaise, ................................. ........................ of the invention in triplicate: 3. ................ ... / .............................................. ..drawing boards, in triplicate; 4. receipt of the fees paid to the Luxembourg Registration Office on .......... September ..... 1988.

5. the delegation of power, dated ......................................... .................................................. .......... the ....................................... .................................................. . 6. the successor document (authorization); declares (s) assuming responsibility for this declaration, that the inventor (s) is (are): (6) - Nagaraj S. Dixit, 7 Berwick Road, Kendall Park,

New Jersey (United States of America) claims (s) for the above patent application the priority of one (or more) application (s) of (7) ............... .brevet _________________________________________________________________________________________ filed (s) in (8) in the United States ...... of America on (9) September 23, 1987 ^ __ under the N ° (10) ............. ... — _________________________________________________________________________________________________________________________________________________________________________________________________ on behalf of (11) ....... 1 'inventor__________________________________________________________________________________________________________________________________________________________________________________________________________ elects (elect) domicile for him (her) and, if designated, for his representative, in Luxembourg_______________ ________________________________ ....... ........... 35, ....... Boulevard Royal______________________________________________ _________________________________________________________________________________________ _________________________ (12) request (s) the grant of a patent for the invention for the subject described and represented in the abovementioned appendices, with postponement of this grant to .............. .................................................. .................................................. .................................................. ............................month. (13) jjerâë & S & a & l agent: ............................................ .................................................. .................................................. .................................................. ............................................... (14) ί \! Λ V V y! Y Bu Deposit Minutes

The aforesaid request for a short film has been lodged with the Ministry of the Economy and the Middle Classes, Service ^ delaj Property InteUectrpôëâjCtBsçmbourg, dated: 2 September 3, 1988 / ÿ * 9 ^ Λ Λ ('' ^ r '* e ^ ™ stre LÉconcrare and Middle Classes, at ................. U> ............ hours I · / 2 j iß. d / yS \ Le head of service Intellectual property, A 68007 /) /! EXPLANATIONS RELATING TO THE DEPOSIT FORM. f (1) if applicable "Application for certificate of addition to the main patent, to the main patent application No ............ of ......... ... ”- (2) enter the last name, first name, profession.

address of the applicant, when the applicant is an individual or corporate name, legal form, address of the head office, when the applicant is a legal person - (3) enter the name. first name, address of professional representative, industrial property attorney, muai of special powers, if applicable: “represented by ........... acting as representative" f 1 Λ - (4) date of filing in full - (5) title of the invention - (6) enter the names, first names, addresses of the inventors or the indication "(see) separate designation (will follow)", when the desi - I * I 'I f) anation is done or will be done in a seoaré document. or the indication "do not mention", when the inventor signs or will have a non-mention document to be added to a withdrawal -,.. 88- / B 52 779

CLAIM OF PRIORITY

of the patent application / utility model læô IN THE UNITED STATES OF AMERICA OF SEPTEMBER 23, 1987 (No. 099.968) Brief Description filed in support of an application for

PATENT

at

Luxembourg on behalf of: Colgate-Palmolive company NEW YORK, N.Y. 10022 (United States of America) for: "Thick aqueous detergent composition containing little or no phosphate and method of washing dishes using it." ((

THICKENED AQUEOUS DETERGENT COMPOSITION CONTAINING LITTLE OR

NO PHOSPHATE AND DISHWASHING METHOD

USING IT.

The present invention relates to aqueous caipcsiticns for washing dishes and the like, especially in an automatic dishwasher. More specifically, the invention relates to compositions which do not contain phosphate builders but which have a detergent power comparable to or better than similar liquid detergent compositions for automatic dishwashers containing phosphorus.

The present invention specifically relates to thickened liquid detergent compositions for automatic dishwashers having viscoelastic properties, improved chemical and physical stability, and increased detergency despite the absence of adjuvant phosphate salts and which are spontaneously dispersible in the media. washing to provide effective washing of dishes, glassware, porcelain etc.

Detergents for household dishwashers commercially available in powder form have several disadvantages, e.g. a non-uniform composition; costly operations for their production; a tendency to agglomerate in storage for high humidity levels, and thus to form clusters which are difficult to disperse; dust, a particular source of irritation for allergic users; and tendency to agglomeration in the dishwasher dispenser. The liquid forms of these compositions, however, generally cannot be used in automatic dishwashers because of their high foam percentages, their unacceptably low viscosities and their far too high alkalinity.

Recent research and development activity c ο

Iw has looked at the gel or “thixotropic” form of such compositions, eg. degreasers and products for automatic dishwashers characterized by thixotropic liquids or pastes. Dishes for dishwashing thus obtained are essentially questionable in that they are insufficiently viscous to remain "anchored" in the dispenser of the dishwasher, and moreover leave stains on dishes, glassware, porcelain etc.

The presentation of compositions for automatic dishwashers in gel form and having satisfactory stability and detergent properties has hitherto been problematic, particularly with regard to compositions for use in domestic dishwashers. For effective use, it is generally recommended that the automatic dishwashing detergent, hereinafter referred to as ADD, contains <1) sodium tripolyphosphate CNaTPP) to soften or fix the minerals in hard water and emulsify and / or peptize the dirt; (2) sodium silicate to provide the alkalinity necessary for effective cleaning and to protect varnish and pattern from fine porcelain; (3) sodium carbonate, generally considered optional, to increase the alkalinity; (4) a chlorine-releasing agent to assist in the removal of soils which lead to the formation of water spots; and (5) a defoamer / surfactant to reduce foam, thereby increasing the efficiency of the machine and providing proper cleaning. See, for example, SDA Detergents in Depth, "Formulations Aspects of Machine 30 Dishwashing", Thomas Oberle <1974). The cleaning products corresponding roughly to the compositions described above are mostly liquids or powders. combination of such ingredients in thickened form suitable for domestic machines has proven difficult.

Generally such compositions do not contain hypochlorite bleaching agents since it tends to react with other chemically active ingredients, in particular (4 η u surfactants, thereby degrading the suspending agent or the thickener and decreasing its effectiveness.

U.S. Patent 4,115,308 describes thixotropic pastes for automatic dishwashers containing a suspending agent, eg CMC, synthetic clays etc .; inorganic salts including silicates, phosphates and polyphosphates; a small amount of surfactant and an antifoam. There is no mention of bleach. On the other hand, U.S. Patent 3,684,722 describes a detergent composition based on alkali cPhypochlorite and thickened using mixtures of alkaline soaps in C ~ Ct8 and hydrotropes, such as amine oxyfles and betaines. The inventors describe tests which show that various classes of organic polymeric thickeners were either unstable or fail to provide suitable thickening or cause loss of available chlorine. The polyacrylates were able to cause thickening for several weeks at room temperature, but then decomposed.

Patent US 3,985,668 describes abrasive degreasers of gel consistency containing Cl) a suspending agent, preferably clays of the smectite or attapulgite type; (2) an abrasive, eg silica sand or perlite; and ¢ 3) a filler comprising low density powdered polymers, expanded perlite, etc., which has buoyancy and therefore a stabilizing effect on the composition in addition to its filler function, thus replacing the water with elsewhere available for the formation of an undesirable supernatant layer due to seepage and phase destabilization. The above ingredients are the essential ingredients. Optional ingredients include a hypochlorite bleach, surfactant. resistant to bleaching and buffering, eg silicates, carbonates and monophosphates. Adjuvants such as NaTPP may be included as additional optional ingredients to establish or supplement an auxiliary function not fulfilled by the buffer, the amount of such an adjuvant not exceeding 5% of the total composition, according to the patent. Maintaining pH levels at desired values (more than) is achieved by the buffer / adjuvant components. A high pH is believed to decrease the decomposition of the chlorine bleach and the undesirable interaction between the surfactant and the bleach. When present, NaTPP is limited to 5% as indicated. There is no mention of antifoam.

In Patent Applications ΘΒ 2.116.199A and 6B

2.140.450A, both in the name of Colgate-Palmolive, cPADD (LADD) liquid compositions are reported which have properties advantageously characteristic of a thixotropic gel-like structure and which contain various ingredients necessary for effective cleaning with a automatic dishwasher. The aqueous detergent composition for automatic dishwashers normally in gel form having thixotropic properties includes the following ingredients, on a weight basis: (a) 5 to 35% alkaline tripolyphosphate; (b) 2.5 to 20% sodium silicate; 20 Ce) 0 to 9% alkali carbonate;

Cd) 0.1 to 5% of active organic detergent material dispersible in water and resistant to chlorinated chlorinating agents;

Ce) 0 to 5% of antifoam stable to chlorinated bLarrhimart agents;

Cf) chlorine bleaching compound in sufficient quantity to give about 0.2 to 4% of available chlorine;

Cg) thixotropic thickener in an amount sufficient to impart to the composition a thixotropy index of 2.5 to 10 approximately;

Ch) sodium hydroxide in an amount necessary to adjust the pH; and 30 Ci) water;

The LADD compositions thus formulated are weakly foaming; and spontaneously soluble in the washing medium and of maximum efficiency for alkaline pH values. The compositions normally have the consistency of a gel, i.e., a highly viscous opaque jelly-like material having Bingham plasticity and thus relatively high flow thresholds.

f φ 5

Consequently a defined shear force is necessary to initiate or increase the flow, as it can be obtained within, of a dispensing tank with stirring of an automatic dishwasher in action.

Under such conditions the composition is quickly fluidized and easily dispersed. When the shear force is no longer applied, the fluid composition quickly regains a high viscosity, the Bingham plasticity returning very close to its previous consistency.

U.S. Patent 4,511,487, dated April 16, 1985, describes a low foaming detergent paste for dishwashers. The patented thixotropic detergent has a viscosity of at least 30 Pa.s at 20 ° C determined using a rotary viscometer at a spindle speed of 5 15 revolutions per minute. The composition is based on a mixture of hydrated sodium tripolyphosphate and finely divided hydrated sodium metailicate, an active chlorinated compound and a thickening agent which is a hectorite-type lamellar silicate. Small amounts of nonionic surfactants and alkali carbonates and / or alkali hydroxides can be used.

Recently the Applicant has developed various modifications and improvements in the liquid detergent compositions of the automatic dishwashers of the patents GB 2.116.199A and GB 2.140.450A. For example application FR.No. 86.18377 describes thixotropic liquid detergent compositions of the aqueous gel type and free of clay and thickener, which use a mono- or polycarboxylic acid of S with 22 carbon atoms to confer physical stability and thixotropic properties.

In the French application N ° 87'.12321 filed on 4/9/87 the physical stability of detergent compositions for automatic dishwashers made of thixotropic liquid based on clay is improved by the addition of 35 small quantities, for example of about 0.02 to 17. by weight, a polyvalent metal salt of a long chain fatty acid, such as aluminum stearate.

f s

The majority of these automatic detergent and similar liquid dishwasher compositions described and marketed depend on phosphate salts as adjuvants such as sodium tripolyphopshate to increase the cleaning capacity. While these phosphate additives are very effective for this purpose, their use has a major drawback: they are harmful to aquatic life and to rivers, in general. In fact many jurisdictions have already, or are in the process of absolutely banning phosphate-based cleaning products.

Although there have been multiple attempts to produce substitute adjuvants and many such salts of inorganic and organic non-phosphate detergents are known, very few are able in practice to provide cleaning benefits comparable to those phosphate additives. In addition, the choice of suitable adjuvants is all the more difficult in view of current aqueous compositions which contain bleaches, since the replacement adjuvant must be compatible with the chlorinated bleaching agent.

In addition to its function as a detergency builder, inorganic alkali metal phosphate has the important function of contributing to the rheological properties of liquid aqueous detergent compositions of the thickened thixotropic gel type as described in GB 2.116.199A and GB 2.140.450A. Consequently, the replacement of the phosphate adjuvant by a non-phosphate adjuvant has not proved to be simple since there are many various factors to be taken into account in order to meet all the multifunctional missions of the phosphate adjuvant.

It is therefore the first object of the invention to provide aqueous cleaning compositions containing a bleaching agent which avoid the use of phosphate builders and which do not contain, or only environmentally acceptable levels of phosphorus from other sources.

It is another object of the invention to provide thickened liquid ADD compositions containing little or no phosphate and having improved physical stability and rheological properties.

It is still another object of the invention to provide thickened liquid ADD compositions having little or no phosphorus without adversely affecting, or improving, the cleaning capacity, in particular by the formation of a small amount of spots and films.

These and other objects of the invention, which will be more easily understood from the following detailed description of the invention and its preferred embodiments, are achieved by means of a liquid aqueous detergent composition containing little or no phosphorus and comprising water, an organic detergent dispersible in water and stable to 13 egstins of blanchinrat cfrLares, a agait dl chlorinated chlorine, an alkaline silicate and a detergency builder, where 11 detergency builder is formed of a mixture aluminosilicate zeolite and a water-soluble polymer stable to btarrhimart agaibs and having a carboxyl group, or a salt thereof. More particularly, according to a preferred and specific embodiment of the invention, a thickened viscoelastic liquid detergent composition for a dishwasher is produced, free from phosphate-containing adjuvant salts and containing little or no phosphorus and effective in preventing the deposition of particles. suspended in water insoluble, such as adjuvant aluminosilicate zeolite particles and bleaching agent, eta. The composition can include clay or other thickeners as well as other stabilizers and other conventional cFADD additives.

According to this particular aspect the present invention provides an aqueous detergent composition normally of gel type for automatic dishwasher and having viscoelastic properties, which comprises, by weight: ta) 5 to 35% of aluminosilicate zeolite; 35 Cb) 25 to 40% sodium silicate;

Ce) 0 to 9% alkali metal carbonate; td) 0.1 to 5% active ingredient organic detergent 8 dispersible in water and stable to chlorine bleaching agents;

Ce) O à 5% cPantifoam resistant to chlorinated bLanchiniait;

Cf) a chlorinated compound acted from bLardunait. have sufficient quantity 5 to supply about 0.2 to 4% of available chlorine;

Cg) O at 0.5% of a long chain fatty acid or a salt thereof;

Ch) 0 to 5% of a clay thickener;

Ci) O to 8% sodium hydroxide; and 10 Cj) complementary water.

Also in connection with this specific aspect, the invention provides a method of cleaning dishes in an automatic dishwasher with an aqueous washing bath containing an effective amount of the liquid detergent composition for automatic dishwasher CLADD) described above. -above. According to this aspect of the invention, the LADD composition can be poured directly into the dispenser of the automatic dishwasher and will be viscous enough to remain safely inside the tray until shear forces are applied. are applied to it, such as those coming from the water jet of the washing machine, forces making it possible to exceed the flow threshold of the composition which will then flow.

The invention will now be described in more detail using specific embodiments.

In view of the environmental problems caused by the elutriation of lakes, rivers and other watercourses attributed to the deposition of phosphorus from detergents and other products in watercourses, much emphasis has been placed on the elimination phosphorus from detergent products.

However, attempts to replace the phosphate adjuvant in thixotropic liquid compositions for automatic dishwashers of the type used by the applicant and which typically contain 0 to 3% c Clay thickener - generally of the smectite type swelling with water; 10 to 25% alkali silicate; 0 to 0.5% stabilizing fatty acid; small amounts of bleach, bleach-stable detergent 9, bleach-stable antifoam, sodium carbonate, caustic soda, etc., and approximately 20 to 25% alkaline phosphate as an adjunct to decay, has led to loss thixotropic properties and generally a deterioration in cleaning efficiency-Although the exact mechanism for the destruction of rheological properties causing loss of thixotropy has not been fully elucidated, it appears that there is at least one interactioin between the particles of phosphate additive in suspension and the other ingredients of the formulation, especially the clay thickener and the fatty acid or the stabilizing fatty acid salt and this interaction contributes to increasing the shear stress and the plastic viscosity of the composition.

The present invention is based on the surprising discovery that similar rheological properties and similar physical stability, i.e. resistance to phase separation, sedimentation, etc., can be achieved, as in the compositions 20 prior phosphate aqueous liquids, including in the composition an aluminosilicate zeolite as a water-insoluble inorganic detergent builder mixed with a water-soluble and bleach-resistant carboxyl group polymer as a rheological agent and multifunctional detergent builder, and increasing the percentage of alkali silicate at more than 25% by weight. At the same time, better results are obtained with regard to stains and films (that is to say less stains and a reduction in films).

Although the compositions of the present invention do not exhibit thixotropic properties, they exhibit viscoelastic properties and have a flow threshold Qa maximum tension on a shear tension curve versus shear rate) sufficiently high that they do not flow under the effect of the force exerted by their own weight, that is to say the gravitational forces. Consequently, the compositions according to the invention can be easily poured into the dispensing tank of an automatic dishwasher and will not flow until a sufficiently strong shearing force is applied such that the force of the jets of water exerted on the tank during the detergent dispersion cycle.

Naturally, it is understood that when physical stability over extended periods such as several weeks or several months is not required and when a very thick solution is not requested, the rates can be subtracted from the formulation silicate, the clay thickener and / or the fatty acid or its stabilizing salt without adversely affecting the cleaning capacity given by the aluminosilicate zeolite additive and the bleach-stable polymer containing a carboxyl group (one of its salts) water soluble.

The useful additives here are the water-insoluble aluminosilicates, whether crystalline or amorphous. Different zeolites are described in patent 6B 1,504,168, U.S. patent 4,409,136 and Canadian patents 20 1,072,835 and 1,087,477, all taken into account here as a reference for such descriptions. An example of amorphous zeolites useful here can be found in Belgian Patent 835,351 and this patent is also incorporated here for reference. Zeolites generally have the formula 25 CM20) x.CAl2035y.CSiGz): i: .WHa0 where x is 1, y is between 0.8 and 1.2 and preferably 1, z is between 1.5 and 3 , 5 or more and preferably 2 to 3 and w is between 0 and 9, preferably 2.5 to 6 and M is an alkali metal, preferably sodium or potassium, preferably especially sodium. A typical zeolite is of type A or similar structure, with type 4A being particularly preferred. Preferred aluminosilicates have calcium ion exchange capacities of about 200 milliequivalents s per gram or more, eg 400 meq / g.

The aluminosilicate zeolite builder can be present in the formulations in the same amounts as those found useful for the alkaline polyphosphate builders, it generally in the range of from about 5 to 35X by weight, preferably about 20 to 30X, weight.

The water-soluble polymers used here, which are stable to bleaching and contain carboxyl groups, are, for example, homopolymers and copolymers of acrylic acid and their salts. These materials are generally commercially available and can be described as below.

Polyacrylic polymers and their salts which can be used include water-soluble low molecular weight polymers having the formula | R * R = |

I I I I

15 -1-c- C-1-

III I

| R3 COOM I

L ..i n where Rs, and Ra may be the same or different and may be hydrogen, C1-C4 lower alkyl, or combinations thereof; n is a number from 5 to 250, preferably from 10 to 150, and even better from 20 to 100; and M represents hydrogen or an alkali metal, such as sodium or potassium. The preferred substituent for M is sodium. 25- The preferred groups Ri, RÂ and Ra are hydrogen, methyl, ethyl and propyl. The preferred acrylic monomer is that where Ri and Ra are hydrogen, e.g. acrylic acid, or where Ri and Ra are hydrogen and R2 is methyl, for example the methacrylic acid monomer.

The degree of polymerization, i.e., the value of n, is generally determined by the limit compatible with the solubility of the polymer or copolymer in water. The terminal or final groups of the polymer or copolymer are not critical and may be H, OH, CH3 or a low molecular weight hydrocarbon.

Typically, polyacrylic acid copolymers may contain copolymers of, for example, acrylic acid 12 or methacrylic acid and an acid anhydride or polycarboxylic acid such as succinic anhydride, succinic acid, maleic anhydride, maleic acid, citric acid, etc. Preference is given to copolymers of acrylic or methacrylic acid with maleic anhydride.

The acrylic acid or methacrylic acid monomer will usually contain from 40 to 60% by weight, eg about 50% by weight of the copolymer with a polycarboxylic acid or anhydride.

The polyacrylic acid polymer can have a molecular weight (average weight from 500 or 1000 to 25,000, preferably 1500 to 15,000 and more preferably 2000 to 10,000. The copolymers can have higher molecular weights, for example up to about 100,000. Specific examples of the polyacrylic acid polymers which can be used include Acrysol LMW acrylic acid polymers from Rohm and Haas, such as Acrysol LMW-45NX, a neutralized sodium salt, which has a molecular weight of about 4500 and Acrysol LMW20-NX, a neutralized sodium salt, which has a molecular weight of approximately 2000.

A specific example of an acrylic acid copolymer which can be used is Sokalan CP5 (from BASF) which has a molecular weight of about 70,000 and is the product of the reaction of an approximately equal number of moles of methacrylic acid and maleic anhydride which has been completely neutralized to form its sodium salt.

The above polymers and copolymers can be prepared according to methods known in the prior art.

30 See, for example, U.S. Patent 4,203,858.

The bleach-stable carboxylated water-soluble polymers have been shown to have three primary functions in the liquid detergent compositions for automatic dishwashers of this invention: rheology control; calcium complexation; and dispersion of dirt;

As a rheological control agent, the polymer additive apparently functions as a thickener and, with the help of high percentages of alkali silicate, clay (when presented) and acid (or salt). fatty acid (when present), it communicates the viscoelasticity to the composition and a plastic viscosity which is in the range of about 200 to 10.ÖG0 mPa.s, preferably 2000 to 8000 p. eg 5000 irÊ “as The desired viscoelasticity and plastic viscosity ranges are best achieved when the molecular weight is not more than 10,000, especially from 2,000 to 10,000, e.g.

10 approximately from 4000 to 5000.

As a calcium complexing agent it is important that the polymer has a particularly good water solubility. Here again, the best results are obtained when the polymer has a molecular weight of not more than 10,000, especially 2,000 to 10,000.

Similarly, in its agent action dispersed the dirt contributing to the desired improved stain and anti-film properties, the molecular weights of the additive polymer are preferably in the range of 2000 to 10,000.

The amount of additive polyacrylic acid polymer or copolymer required to achieve the desired increase in physical stability and cleaning performance will depend on factors such as the amount and nature of the fatty acid or its salt (when present) , the nature and amount of the clay thickener (when present), the active detergent component, the bleaching agent, as well as the expected storage and shipping conditions.

Generally, however, the amounts of additive polyacrylic polymer or copolymer which can be used are in the range of about 0.5 to 10% by weight, preferably about 0.80 to 8.0% by weight, and especially about 2 to 6% by weight.

The detergent active material useful here must be stable in the presence of chlorinated blaxhimite agent, especially hypochlorite, and the types of water-dispersible surfactants such as organic anionics, amine oxides, oxides are preferred. phosphine, sulfoxides or betins, the first anionics mentioned having preference. They are used in amounts ranging from about 0.1 to 5%, preferably about 0.3 to 2.07. Particularly preferred surfactants here are the mono- and / or oxide disulfates of mono- and / or di- (CQ-C x. ”lcoyldiphenyl alkali linear or branched, commercially available, for example DOWFAX (trade mark! 3B-2 and DOWFAX 2A-1. In general, paraffinic sulfonates tend to abnormally increase viscosity, causing thus serious shear force problems. In addition, the surfactant should be compatible with the other ingredients of the composition. Other suitable surfactants include alkyl sulfates, alkyl sulfonates, primary alkylarylsulfates and secondary alkyl sulfates. Examples include C10-Cia sodium alkyl sulfates, such as sodium dodecylsulfate and sodium tallow alcohol sulfate; C10-Cies sodium alkanesulfonates, such as hexadecyl-1-sodium sulfonate and Cn-Cies alkylbenzenesulf o sodium nates, such as sodium dodecylbenzenesulfonates. The corresponding potassium salts can also be used.

As other suitable surfactants or detergents, amine oxides typically have the structure R ^ RiNO, in which P ^ represents a lower alkyl group, for example methyl, and Ri represents a long chain alkyl group having from S to 22 atoms carbon, for example a lauryl, myristyle, palmityl or cetyl group. Instead of an amine oxide, it is possible to use a phosphine oxide RiRs-PO 30 or a sulphoxide RRiSO corresponding surfactants. Betaine surfactants typically have the structure R2RiN-R "C00-, in which each R represents a lower alikylene group having 1 to 5 carbon atoms. Specific examples of these surfactants are lauryldimethylamine oxide, myristyldimethylamine, the corresponding oxides and sulfoxides of phosphites, and the corresponding betaines, including acetate of * 15!) t dodecyldimethylammonium, tetradecyldiethylammonium pentanoate, hexanoate cf hexadecyldimethylammonium, etc. For the biodegradability, the alkyl groups of these surfactants should be linear, and it is these compounds that are preferred.

Surfactants of the foregoing type are well known in the art and are described, for example, in U.S. Patents 3,9S5,6ÊS and U.S. 4,271,030.

Although any chlorine bleaching compound can be used in the compositions of this invention, such as dichloroisocyanurate, dichlorodimethylhydantoin, or chlorinated TSP, an alkali metal hypochlorite, e.g. potassium, lithium, magnesium, is preferred. especially sodium. The composition should contain sufficient chlorine bleach to provide 0.2 to 4.0% by weight of available chlorine, dosed for example by acidifying 100 parts of the composition with an excess of hydrochloric acid. A solution containing about 0.2 to 4.0% by weight sodium hypochlorite contains or supplies about the same percentage of available chlorine. Preference is given to about 0.8 to 1.8% by weight of available chlorine. For example, a sodium cPhypochlorite solution CMaOCl) having about 11 to about 13% available chlorine in amounts of about 3 to 20%, preferably about 7 to 12%, can be advantageously used.

Sodium or potassium silicate, which provides alkalinity and protection to hard surfaces (such as fine porcelain and pattern), is normally used in amounts ranging from about 2.5 to 20 or 25% by weight. At percentages higher than about 10% by weight, the silicate also has an improved anti-stain action.

However, for the preferred physically stable and viscoelastic aqueous detergent dishwasher compositions of this invention, it is essential to incorporate amounts of alkali silicate in excess of the amounts normally used, especially more than 25% by weight, example from 28% to 40%, more especially about 30 to 38% by weight of the composition.

Sodium silicate is generally added in the form of an aqueous solution, preferably with a ratio 2 NaÄ0: Si0Ä of about 1: 2.2 to 1: 2, S, for example 1: 2.4. Most of the components of the composition, in particular NaQH, sodium hypochlorite and antifoam can also be added in the form of an aqueous dispersion or solution.

Inhibition of foam is important for increasing the performance of the dishwasher and decreasing the destabilizing effects which could occur in the presence of excess foam in the machine during use. The foam can be sufficiently reduced by an appropriate choice of the type and / or the amount of active detergent material, the main foaming component. The amount of foam ^ also depends to some extent on the hardness of the washing water in the machine, so that a proper adjustment of the proportions of NaTFP, which has a softening effect on the water, can help to achieve the desired degree of foam inhibition. However, it is generally preferred to introduce a foam reducer or inhibitor resistant to discoloration by chlorinated agents.

Particularly effective in this regard are the phosphonic addss alkylestecs of the following formula, when a certain percentage of phosphorus can be tolerated: 25 0

There 4

HO — P — R

GOLD

30 and especially the following alkyl acid phosphates

G

II

HO — P — OR

l

DR

17

In the above formulas, one or both R groups in each type of ester may independently represent a C 1-5 alkyl group - COA- The ethoxylated derivatives of each type of ester, for example the condensation products of a 5 mole of ester with, for example from 1 to 10 moles, preferably 2 to 6 moles, better still 3 or 4 moles, of ethylene oxide can also be used. Some of the foregoing products are commercially available, such as SAP products from Hooker and LPKn-158 from Knapsack. Mixtures of both types, or of all other types stable to chlorine-containing agents, or mixtures of mono- and diesters of the same type can be used. There is a special preference for a mixture of acid phosphates of mono- and di-Cie-Cis alkyl such as the acid phosphates of monostearyl / distearyl 1.2 / 1, and their condensates with 3 to 4 moles of oxide of ethylene. In the case where it is used, proportions of 0.01 to 0.5% by weight, preferably 0.02 to 0.4% by weight, in particular approximately 0.1 to 0.2% by weight, of foam reducer in the composition are typical proportions, the weight ratio of active detergent to defoamer generally being between about 20: 1 and 4: 1 and preferably between about 10; 1 and 5: 1. At these low percentages of defoaming agent, the total percentage of phosphorus in the composition will generally and preferably not exceed 0.01% by weight of the total of the composition.

When it is desired to completely eliminate the phosphorus, any silicone antifoaming agent compatible with the bleaching agent can be used.

In the preferred thickened LADD compositions of this invention, thickening is caused by inorganic colloidal water-swelling clays of the smectite and / or attapulgite types. These materials can generally be used in amounts of about 0.1 to 10, preferably 1 to 5% by weight, to impart the desired properties. However, in the presence of fatty acid stabilizers or fatty acid salts, lower amounts of colloidal inorganic clays of the smectite and / or attapulgite types can be used. For example, amounts of clay in the range of about 0.1 to 3%, preferably 0.1 to 2.5X, or better still 0.1 to 2X, are generally sufficient to achieve the viscoelastic properties desired when used in combination with the fatty acid (stabilizing fatty acid salt salt), and other specified ingredients.

Smectites include montmorillonite (Cbentonite), hectorite, attapulgite, smectite, saponite, etc. The 10 montmorillonite clays are preferred and are available under trade names such as Thixogel (trade mark) No. 1 and Gel white (trade mark) GP, H etc-, from Georgia Kaolin Company} and ECCAGUM (trade mark) GP, H etc., of Luthern Clay Products. The cFattapulgite clays include the materials commercially available under the trade name Attagel (trademark), i.e., Attagel 40, Attagel 50 and Attagel 150 from Engelhard Minerais and Chemicals Corporation. Mixtures of smectites and cFattapulgites in weight ratios of 4: 1 to 1: 5 are also useful here. Thickening or suspending agents of the above types are well known in the prior art.

Physical stability, i.e. resistance to phase separation, sedimentation, etc. of these cFADD aqueous liquid compositions can be significantly improved by adding to the composition a small but effective amount of a long chain fatty acid or a metal salt thereof. In fact, under the preferred alkaline pH conditions of the LADD composition, ie pH 10.5 to 13.5, the fatty acids will be converted into the corresponding alkali metal salts.

Preferred long chain fatty acids are higher aliphatic fatty acids having from about 8 to about 22 carbon atoms, preferably from about 10 to 35 carbon atoms, and more preferably from about 12 to 18 carbon atoms. carbon, including the carbon atom of the carboxyl group of the fatty acid. The aliphatic radical can be 13 ″ saturated or unsaturated and can be linear or branched. Straight chain saturated fatty acids are preferred. Mixtures of fatty acids can be used, such as those derived from natural sources such as tallow fatty acid, coconut fatty acid, soy fatty acid, etc., or from synthetic sources which are industrial manufacturing processes.

Thus, examples of fatty acids are, for example, decanoic acid, dodecanoic acid, palmitic acid, myristic acid, stearic acid, oleic acid, eicosanoic acid, l tallow fatty acid, coconut fatty acid, soy fatty acid, mixtures of these acids, etc. Stearic acid and mixed fatty acids are preferred.

The metal salts of fatty acids can also be used and any monovalent or polyvalent metal can be used. Monovalent metals include, for example, alkali metals, especially sodium and potassium. Sodium salts (soaps) are particularly preferred.

The preferred polyvalent metals are the polyvalent metals of groups IIA, IIB and IIIB of the Periodic Table of the Elements, such as magnesium, calcium, aluminum and zinc, although other polyvalent metals, including those of groups IIIA, IVA, VA, IB, IVB, VB, VIB, VIIB and VIII of the Periodic Table can also be used. Specific examples of such other polyvalent metals are Ti, Zr, V, Nb, Mn, Fe, Co, Ni, Cd, Sn, Sb, Bi, etc. Generally metals can be present in a divalent to pentavalent state. Preferably, the polyvalent metal salts are used in their higher oxidation states.

Naturally, for LADD compositions, as well as for all other applications or the composition according to the invention interviehdra, or may be involved, in articles used for the handling, storage or presentation of food, or which may be at contact or consumed by people or animals, the metal salt should be chosen taking into account the toxicity of the metal. To this end, the calcium and magnesium salts are given special preference as generally healthy food additives.

Many of these metal salts are commercially available. For example, aluminum salts are available in triacid form, eg aluminum stearate as aluminum tristearate, AKCx ^ HasCOCDa. The monoacid salts, eg aluminum monostearate, and the diacid salts, eg aluminum distearate, and mixtures of two or three of the mono-, di- and triacid salts may Used for metals, eg Al, with valences +3, and mixtures of the salts of mono- and diacids can be used for metals, eg Zn with valences +2. It is highly desirable that the valence metal diacids +2 and the valence metal triacids +3, the valence metal tetracids +4 and the valence metal pentacids +5, be used in predominant amounts.

The metal salts mentioned above are generally commercially available, but can easily be produced, for example by saponification of a fatty acid, e.g. animal fat, stearic acid etc., or the corresponding fatty ester , followed by treatment with a polyvalent hydroxide or metal oxide, for example in the case of the aluminum salt, with alum, alumina, etc., or by reaction of a soluble metal salt with a salt soluble fatty acid.

Calcium stearate, i.e. calcium distearate, magnesium stearate, i.e. magnesium distearate, aluminum stearate, i.e. tristearate d Aluminum and zinc stearate, i.e. zinc distearate, are the preferred polyvalent stabilizing fatty acid salts.

Mixed fatty acids such as acids were found in nature, eg ocprah acid as well as mixed fatty acids resulting from industrial manufacture are also advantageously used as a cheap but valuable source of long chain fatty acid.

In addition, the dimers or trimers of these acids can also be used.

The amount of fatty acids or stabilizing fatty acid salts necessary to achieve the desired improvement in physical stability will depend on such factors as the nature of the fatty acid (its salt), the nature and amount of the clay thickener, active detergent component, inorganic salts, other ingredients of LADD, as well as storage and shipping conditions.

Generally, however, amounts of polyvalent fatty acid salt stabilizers are in the range of about 0.02 to 1%, preferably about 0.05 to 0.8%, preferably still from about 0.08 to 0.4%, offer long term stability and the absence of phase separation during storage or during transport both at low and high temperatures as is desirable for a commercially acceptable product.

Although not wishing to be bound by any particular theory as to the mode of action of fatty acid stabilizers (metal salts), it is hypothesized that these stabilizers, which, under alkaline conditions, are anionic salts, act on the surface of the cationic clay particles used as a thickener, the fatty acid residues helping to keep the clay particles in suspension. In addition, depending on the amounts, proportions and types of physical stabilizers and clay thickeners, the addition of the fatty acid Cou of its salt) not only increases the physical stability but also causes a simultaneous increase in the apparent viscosity. The ratios of the fatty acid (salt salt) to the clay thickener ranging from about 0.08 to 0.4% by weight of clay thickener are generally sufficient to give these simultaneous benefits and, therefore, these ingredients are advantageously used according to these reports.

Generally, the effectiveness of LADD is directly related to Ca) amounts of available chlorine; Cb) alkalinity; This)

solubility in the washing medium; and Cd) inhibition of foams; It is preferred here that the pH of the LADD composition

*> "t · ~ ι or at least about 9.5, better still about 10.5 to 13.5 and even more advantageously at least about 11.5. At relatively low pH values, the LADD product is often too viscous, that is to say almost solid, and thus S therefore not spontaneously fluid under the effect of the shearing forces created within the distribution tank under the normal operating conditions of the machine. Essentially, the composition loses much, if not all, of its viscoelastic character, so the addition of NaOH is often necessary to increase the pH to the above-mentioned intervals, and to increase the rheological properties.] The presence of carbonate is also often necessary here , as it acts as a buffer which helps to maintain the desired pH, however, excess carbonate should be avoided, as it can cause the formation of crystals into carbonate needles, thus altering stability, thixotropy and / or potency product detergent it LADD, at the same time as the distribution of the product from, for example, tubular pressure bottles. Caustic soda additionally has the function of neutralizing the foam reducing phosphoric or phosphonic ester when it is present. About 0.5 to 3% by weight of NaOH and about 2 to 37% by weight of sodium carbonate in the LADD composition are characteristic, although it should be noted that sufficient alkalinity can often be provided by the silicate of alkali metal.

The amount of water contained in these compositions should, of course, not be too high to create an abnormally low viscosity and fluidity, nor too low to create an abnormally high viscosity and low flowability, the viscoelastic properties being in both cases diminished or destroyed. Such a value is readily determined by routine testing in each particular case, and is generally in the range of from about 25 to 75% by weight, preferably about 55 to 65% by weight, in total, of all the sources. The water should also advantageously be deionized or »f

"Q

JÎ.W

softened.

Other conventional ingredients can be introduced into these compositions in small amounts, generally less than about 3% by weight, such as a perfume, hydrotropic agents, such as benzene-, toluene-, xylene-, and sodium cumene sulfonates, preservatives, dyes and pigments, etc., all, well sGr, stable to chlorinated bleach and to high alkalinity (properties of all components). Preferably, preference is given for coloring to chlorinated phthalocyanines and polysulphides of the palmite which gives pleasant green and blue tones, respectively. Ti02 can be used to whiten or neutralize color deviations. Abrasives or polishing agents should be avoided in LADD compositions as they can stain the surface of fine dishes, crystal etc.

According to a preferred method for making these compositions, all inorganic salts, eg carbonate (when used), silicate and zeolite, should first be dissolved or dispersed in the aqueous medium. The thickening components including polymer with carboxylic group and clay (when present) are added last.

The antifoam (when present) is first introduced as an aqueous dispersion, as is the thickening agent. The antifoam dispersion, the caustic soda (when present) and the inorganic salts are first mixed at high temperatures in aqueous solution (deionized water) and then cooled, with constant stirring. The bleach, surfactant, fatty acid (or its stabilizing metal salt), polymer and thickener dispersion at room temperature are then added to the cooled solution (25-35 ° C). Excluding the chlorine bleaching compound, the total salt concentration (eg sodium silicate and sodium carbonate) is generally about 20 to 50% by weight, preferably about 25 to 40% by weight of the composition.

Another particularly preferred method of mixing the ingredients of the LADD formulations is to first form a mixture of water, defoamer, detergent, carboxyl group polymer, fatty acid or salt cFatty acid and clay. These ingredients are mixed together under high shear conditions, preferably initially at room temperature, to form a uniform dispersion. In this premixed fraction the remaining ingredients are incorporated under low shear mixing conditions. For example, the required amount of premix is introduced into a low shear mixer and the remaining ingredients are then added, while mixing, either sequentially or simultaneously. Preferably, the ingredients are added sequentially, although it is not necessary to complete the addition of all of an ingredient before starting the addition of the next ingredient. In addition, one or more of the ingredients can be divided into parts and added at different times. Good results have been obtained by adding the remaining ingredients in the following order: soda, alkali carbonate, sodium silicate, aluminosilicate zeolite, bleach (preferably sodium hypochlorite) and soda.

The liquid ADD compositions of this invention are used directly, in a known manner for washing plates, other kitchen utensils, etc. in an automatic dishwasher provided with a suitable detergent dispenser, in an aqueous washing bath containing an effective amount of the composition.

While the invention has been particularly described with respect to its application to liquid detergents for automatic dishwashers, any person skilled in the art will readily understand that, with or without the advantages of the viscoelasticity and the physical stability obtained thanks to the quantities additional alkali silicate and the interaction of clay and fatty acid, the cleaning benefits provided by the combination of a bleach-stable detergent, bleach, zeolite builder and a water soluble carboxyl group polymer resistant to bleaching agents makes the compositions of this invention useful as a general type of liquid cleaning composition for dishes, glassware, cutlery, pots, pans etc.

The detergent performance of the composition of the invention, in terms of removing a broad spectrum of food stains, is comparable to or slightly better than that of detergents based on a similar alkaline polyphosphate, e.g. sodium tripolyphosphate. For example, in cleaning tests on various food residues, some of them even being cooked on the walls, including egg, peanut butter, tea, coffee, milk, milk chocolate, tomato juice, rice , rice / cheese mixture, white sauce, oatmeal and spinach, the LADD composition of the invention performed a slightly better cleaning or the same cleaning in 14 to 16 cases of food stains on different substrates (glasses, cups, knives, dishes, pots) and cleaning only Barely worse for milk chocolate and cooked rice on the containers.

In addition, as will be shown in the following example, the compositions of this invention are generally superior to similar phosphate compositions in terms of staining and filming.

The invention can be practiced in different ways and a number of specific embodiments have been described to illustrate the invention in the following example.

All amounts and proportions referred to therein are by weight of the composition, unless otherwise indicated.

The following two compositions are prepared so as to compare the properties of the composition according to the invention with a similar phosphate-based composition.

y 26

Component Invention Comparison

Lot N ° 1 Lot M ° 2

Deionized water 16.44 30.44

Stearic acid 0.10 0.10 5 Smectite clay (Van Gel ESI 1.50 1.50

Sodium silicate (47.5X solution of

NaÄ0: Si0z, ratio 1: 2.4) 35.00 25.00 10 Sodium tripolyphosphate (substantially anhydrous, i.e. approx. 3% moisture) 12.00

15 sodium tripolyphosphate, hexahydrate 12.00

Aluminosilicate zeolite 24.00 ----

Carbonate Na, anhydrous 6.00 6.00

Sodium hypochlorite (IX chlorine available) 9.00 9.00 20 Surfactant (Dowfax 3B — 2, 45X aqueous solution of sodium mono- and dode-cyldisulfonate) 0.80 0.80

Antifoaming agent 25 Knapsack LPKn 158, mixture of mono- and distear y 1 (C * e-C ± θ) alkyl esters of phosphoric acid, molar ratio approx. L: 1, 3) 0.16 0.16

Caustic soda solution (NaOH 50X) 3.00 3.00

Na polyacrylate (PM = 4,500) (Solut. 457.) 4.00 ---

Cj ______________________ _______________ 100.00 100.00

Each of the formulations in lots 1 and 2 is tested * "" 27 to compare their cleaning performance (staining and filming on glassware) using a Kenmore dishwasher with 100 grams of glassware and tap water at a temperature 55eC and a hardness of 120 5 ppm. The test procedure is described in ASTM D356G-79, except that only four cleaning cycles are used. Film and stain formations are assessed according to the following scales:

Film rating scale 10 1. Very good, no visible film 2. Slight film, becoming visible 3. Apparent film, increasing 4. Continuous growth of a significant film 25 5. The film becomes excessive G. Film important, excessive formation 7. Continuous growth of excessive film.

Stain assessment scale 20 A. Very good, no spots B. Very few visible spots C. Distinct spots D. Significant coverage around 50%.

25 The results are presented below:

Performance evaluation of Taches Films

Cycle N ° Lot 1 Lot 2 Lot 1 Lot 2 1 A, B B 1.2 1.2 30 2 A, B B 1.2 1.2 3 A, B-B B-C 1.2 1.2 4 B B-C 2 2

Results similar to those described above will be obtained if the polyacrylate is replaced by a methacrylic acid / maleic anhydride copolymer, eg Sokolan CP5.

Claims (20)

1. Aqueous liquid detergent composition containing little or no phosphorus and consisting of water, organic detergent dispersible in water and stable to chlorine bleaches, alkali metal silicate, chlorine bleach and detergency builder, wherein said detergency builder comprises a mixture of alumino-silicate zeolite and a water-soluble carboxylic group polymer stable to bleaching agents. IC 2. Composition according to claim 1, characterized in that the polymer stable to bleaching agents is a polyacrylic acid or a polyacrylate polymer and has a molecular weight in the range from approximately 1000 to approximately 25000. 3. Composition according to claim 2, characterized in that the polymer stable to bleaching agents has a molecular weight of approximately 2000 to approximately 10000. 4. Composition according to claim 1, 2c characterized in that the detergent adjuvant contains from about 5 to about 35 '/ by weight of alu-minosilicate zeolite and from about 0.5 to 107. by weight of polymer stable to bleaching agents. 5. The composition of claim 1, further comprising an inorganic clay thickener forming a colloid. The composition of claim 5, further comprising a C to C aliphatic carboxylic acid or a salt thereof. O d d 7. The composition of claim 1, further comprising a foam reducer stable to bleaching agents. 8. Composition according to Claim 7, characterized in that the foam reducer consists of an alkyl acid phosphate or of an ester 29 4 i -9 of alkylphosphonic acid containing one or two C 1 -C alkyl groups, - C „„, or a mixture thereof. 12 2 0 9. Composition according to claim 1, characterized in that it is an example of phosphorus. 10. The composition of claim 9, further comprising a silicone foam reducer. 11. Aqueous thickened detergent composition for automatic dishwashers containing not more than about 0.01 by weight of phosphorus, and containing approximately 10 by weight, (a) 5 to 35% of aluminosilicate zeolite; (b) more than 25 /. sodium silicate; (c) 0 to 9 / of alkali metal carbonate: (d) 0.1 to 5 /. an organic detergent active ingredient dispersible in water and stable to bleaching agents; (e) 0 to 5 /. foam reducer stable to bleaching agents; (f) a chlorine bleaching compound in sufficient quantity to produce about 0.2 to 4% of available chlorine; (g) 0 to 3 /. an inorganic clay thickener forming a colloid; (h) 0 to 0.5 / of an aliphatic fatty acid having 8 to 22 carbon atoms, its dimers, its trimers, or its metal salts; (i) 0 to 8 / sodium hydroxide; (j) 0.5 to 10 μm of polymer with a water-soluble carbo-xyl group and stable to bleaching agents; and (k) water; said composition having a pH of at least 9.5. 12. Composition according to claim 11, characterized in that the decolourable polymer is polyacrylic acid or a polyacrylate and has a molecular weight of approximately 1000 to 25000. 13. Composition according to claim 12, characterized in that the polymer stable to bleaching agents has a molecular weight of approximately 2000 to approximately 10000. 14. Composition according to claim 11, comprising 0.03 to 0.5 of said aliphatic fatty acid or its salt (h) and 0.1 to 3 /. of said clay thickener io (g) · 15. Composition according to claim 14, characterized in that the fatty acid is stearic acid or a salt of this acid and the clay is a smectite or an attapulgite. 16. Composition according to Claim 11, characterized in that the chlorine-containing bleaching compound (f) is sodium hypochlorite. 17. Composition according to claim 11, characterized in that it contains at least about 2C 0.1% by weight of the foam reducer (e). 18. Composition according to Claim 17, characterized in that the foam reducing agent is an alkyl acid phosphate or an alkyl phosphonic acid ester containing one or two alkyl groups in 25 C12 ~ C20 '° U mixtures thereof 19. The composition of claim 11, having a pH of about 10.5 to about 13.5. 20. A method of cleaning dirty dishes in an automatic dishwasher which consists in contacting, in an automatic dishwasher, dirty dishes with an aqueous washing bath containing in dispersion an effective amount of the composition according to claim 11.