EP0670880A1

EP0670880A1 - Silicon-free foam-control agent

Info

Publication number: EP0670880A1
Application number: EP94901842A
Authority: EP
Inventors: Wolfgang Seiter; Claus-Peter KURZENDÖRFER; Hans-Josef Beaujean; Eric Sung; Karl Schwadtke
Original assignee: Henkel AG and Co KGaA
Current assignee: Henkel AG and Co KGaA
Priority date: 1992-11-30
Filing date: 1993-11-22
Publication date: 1995-09-13
Also published as: DE4240166A1; WO1994012604A1

Abstract

The invention concerns mixtures of anti-foaming agents which are suitable for use in surfactant-containing washing and cleaning agents and which can be adsorbed on granular water-soluble or water-dispersable substrate materials. The aim of the invention is to improve the ability of such mixtures to be converted into a pourable foam-control agent and also to improve their effectiveness over a wide temperature range, while ensuring that both the mixture of anti-foaming agents and the foam-control agent containing it remain stable during storage and retain their action when mixed with the other usual ingredients of washing agents, and do not have any detrimental effects on the materials to be washed or on the environment. This is achieved essentially by preparing a mixture of anti-foaming agents containing 0.1 to 20 % by wt. of a ketone having long-chain alkyl or alkenyl groups with a total of at least 25 C-atoms and 70 to 99.9 % by wt. of a paraffin wax or paraffin-wax mixture which is solid at room temperature and which is 100 % liquid at a temperature below 90 °C.

Description

'Silicon-free foam control agent'

The invention relates to a homogeneous defoamer mixture which contains long-chain alkyl or alkenyl radicals containing ketone with at least 25 C atoms and a paraffin wax which is solid at room temperature, a pourable and free-flowing foam control agent, containing water-soluble or water-dispersible carrier material and defoamers adsorbed thereon mergemix, and a process for the production of such foam regulating agents.

Long-chain ketones of the type concerned here and their preparation are known, for example from German Offenlegungsschrift DE 25 53990. The ketones are prepared by catalytic elimination of CO2 and water from higher monocarboxylic acids, in particular higher fatty acids or their salts. Their use as a means for special foam control in the paint, paper and food industry is described in the aforementioned publication. From the European patent application EP 324339 it is known to use corresponding ketones in detergents containing active chlorine. There, however, the ketones are used as a dispersion in liquid organic carriers. Furthermore, it is known from German Offenlegungsschriften DE 1467 613 and DE 2242 541 to use ketones as foam inhibitors in detergents containing soap. In the absence of soaps and additional foam inhibitors, such as acetals and ketals, their action is insufficient in such compositions.

The object was accordingly to provide a defoaming mixture which is effective in detergents over a wide temperature range, that is to say in particular in the cold washing range and at medium washing temperatures, but also in the hot washing range, suppressing disruptive foaming. Furthermore, the defoamer mixture should be able to be made up into a free-flowing foam regulating agent which, when mixed with conventional detergent constituents, has a stable storage and action remains and has no adverse effects on the material to be treated and the environment.

Surprisingly, it has now been found that the existing problem can be solved by defoamer mixtures of long-chain ketones and paraffin waxes with a relatively narrow melting range.

The invention accordingly relates to a homogeneous defoamer mixture which is particularly suitable for adsorption onto a granular, water-soluble or water-dispersible carrier material

(a) 0.1% by weight to 30% by weight of a long-chain alkyl or alkenyl radical-containing ketone with a total of at least 25 carbon atoms and

(b) 70% by weight to 99.9% by weight of a paraffin wax or paraffin wax mixture which is solid at room temperature and which is 100% by weight in liquid form at a temperature below 90 ° C.

The defoamer mixture preferably contains 1% by weight to 25% by weight, in particular 5% by weight to 18% by weight of ketone (a) and 75% by weight to 99% by weight, in particular 82% to 95% by weight paraffin wax (b).

Another object of the invention is a granular, free-flowing foam control agent, consisting of (I) a granular, phosphate-free, water-soluble or water-dispersible carrier material and (II) a homogeneous defoamer mixture adsorbed thereon, as mentioned above, which comprises 80% by weight to 99% 5% by weight, in particular 88% by weight to 98% by weight of carrier material (I) and 0.5% by weight to 20% by weight, in particular 2% by weight to 12% by weight of defoamer mixture (II) contains.

The foam regulating agent according to the invention preferably contains 80% by weight to 99.5% by weight, in particular 88% by weight to 98% by weight, of carrier material (I) and 0.5% by weight to 20% by weight, in particular Contain 2 wt .-% to 12 wt .-% defoamer mixture (II).

Preferred component (a) of the defoamer mixture are ketones which can be obtained by reacting linear or branched, saturated or unsaturated carboxylic acids or carboxylic acid mixtures in which the car- bonic acids have more than 12 carbon atoms, in particular a carbon chain length of C14 to C30 and react during the ketonization with elimination of carbon dioxide and water. Particular preference is given to ketones which are obtained from the ketonization of carboxylic acids or carboxylic acid salts with a carbon chain length of Ciβ to C22 and mixtures thereof. The ketones can usually be prepared at temperatures in the range from about 200 to 350 ° C. in the presence of metal oxides or fatty acid metal compounds. Both starting materials with a uniform number of carbon atoms and fatty acid mixtures of natural origin can be used. These mixtures can also contain carboxylic acids with 12 and fewer C atoms, provided there is an excess of fatty acids with 14 and more C atoms. This results in mixtures of symmetrical and asymmetrical ketones, whereby the asymmetrical ketones can also have shorter chains than C14 or C12 depending on the material used, provided there is a longer-chain residue in the molecule, so that the total number of C atoms is at least 25 on average is. Examples are Heptacosanon-14, Hentriacontanon-16, Pentatriacontanon-18, Non-atriacontanon-20, Triatetracontanon-22 and Nonacosanon-15, Tritriacon- tanon-17, Heptatriacontanon-19, Hentetracontanon-21 and the like. Ketones or ketone mixtures of the type described are usually solid at room temperature and have melting points in the range from 60 ° C. to 105 ° C.

The ketones are preferably in finely divided form and in particular have an average grain size of less than 50 μm. The information regarding the particle size relates to the known determination method with the "Coulter Counter".

The paraffin wax contained in the defoamer mixture (component b) is generally a complex mixture of substances without a sharp melting point. For characterization, its melting range is usually determined by differential thermal analysis (DTA), as described in "The Analyst" 87 (1962), 420, described, and / or its freezing point. This is the temperature at which the paraffin changes from the liquid to the solid state by slow cooling. Paraffins that are completely liquid at room temperature, i.e. those with a solidification point below 25 ° C, not usable according to the invention. Waxes which solidify in the range from 30 ° C. to 90 ° C. are preferably used. It should be noted that even paraffin wax mixtures which appear solid at room temperature can contain different proportions of liquid paraffin. In the paraffin waxes which can be used according to the invention, this liquid fraction is as low as possible and is preferably completely absent. Preferred paraffin wax mixtures have a liquid fraction of less than 10% by weight at 30 ° C., in particular 2% to 5% by weight, and a liquid fraction of less than 30% by weight at 40 ° C. preferably from 5% by weight to 25% by weight and in particular from 5% by weight to 15% by weight, at 60 ° C. a liquid fraction from 30% by weight to 60% by weight, in particular by 40 % By weight to 55% by weight, at 80 ° C a liquid fraction of 80% by weight to 100% by weight, and at 90 ° C a liquid fraction of 100% by weight. The temperature at which a liquid content of 100% by weight of the paraffin wax is reached is still below 85 ° C., in particular at 75 ° C. to 82 ° C., in particularly preferred paraffin wax mixtures.

Paraffin waxes which can be used according to the invention are, for example, Lunafle® ( ^R ) 902 from Füller and Deawaχ ( ^R ) DEW 5419 from DEA Mineralöl AG.

The defoamer mixture can be prepared by introducing the finely divided ketone (component a) into a melt of component (b) and homogenizing it by intensive mixing. For this purpose, the melt should have a temperature of at least 60 ° C and at most 200 ° C. The temperature is preferably 80 ° C. to 160 ° C. It is essential for a good effectiveness of the defoamer that there is a stable dispersion of the ketone particles in the paraffin matrix, which can be brought about by a particle size corresponding to the definition mentioned. To achieve this state of dispersion, a ketone can be used and dispersed which has the appropriate particle size from the outset, or a coarser starting material is used and the melt is subjected to grinding treatment using colloid mills, tooth mills or ball mills until the desired particle size is reached is. A complete melting of the ketone in the paraffin melt and subsequent rapid cooling to temperatures below the solidification point of the ketone with simultaneous homogenization of the melt can also lead to a correspondingly fine particle size distribution of the ketone. A further advantage of the defoamer mixture according to the invention is that the long-chain ketones have a significantly higher thermal capacity than conventional defoamer constituents based on carboxylic acid-bisamide.

A foam regulating agent according to the invention can be produced by applying the molten defoamer mixture (II) to a granular carrier material (I), for example by successive admixing, in particular as a spray, to the carrier grain. The carrier grain, which can be produced in the usual way by spray drying an aqueous slurry of carrier salts, is kept in motion by mixing elements or by fluidization in order to ensure a uniform loading of the carrier material. The spray mixers used for this can be operated continuously or discontinuously.

One embodiment for the production consists in hurling the granular carrier material in a continuous stream through the likewise continuously generated spray zone of the at least partially melted defoamer mixture, whereby retention times of the carrier material in the hot spray zone of mostly less than 1 second can be achieved . Furthermore, it is possible immediately afterwards to cool the particles of the foam regulating agent with the aid of a gas stream, so that the thermal loads on the material can be kept extremely low.

The method described above uses a type of method as is known, for example, from EP 48312. In this publication, a wheel-shaped mixing device is described as a device for carrying out the method, in which two individually designed and driven wheel-shaped disks are superimposed. The solid powder is fed to one disk, the liquid component below is charged with the liquid component. Both discs run at high rotational speeds, which can range from a few 100 to a few 1000 revolutions per minute. The respective pressurized writing surfaces and in particular the edge of the disk carrying the liquid are designed in such a way that on the one hand the spray zone is thrown off and continuously replicated from the edge of the wheel running at high speed of rotation, on the other hand the granular element continuously supplied to the other wheel-shaped element Material thrown through this spray zone of the liquid phase. Because of the high working speed, the two material phases come into very short contact with one another and thus only a very short time contact of the solid particles with the warm or hot spray phase. The method can be carried out particularly well with the device described in EP 48 312, but it is not restricted to devices of this type. It is essential to set a relatively short contact time, which is achieved by the solid material being thrown through a continuously generated spray zone, the solid material optionally being able to be cooled in front of and / or behind the spray zone.

In a further embodiment of the invention, the foam regulating agent is prepared by dissolving or slurrying the carrier material (I) in water, dispersing the defoamer mixture (II) therein and then spray-drying this slurry. A water-soluble, non-surfactant dispersion stabilizer in the form of a water-swellable polymer is preferably added to the dispersion, since the components of the defoamer mixture are generally not sufficiently soluble in the aqueous slurry. Examples of these are the cellulose ethers mentioned, homo- and copolymers of unsaturated carboxylic acids, such as acrylic acid, maleic acid and copolymerizable vinyl compounds, such as vinyl ether, acrylamide and ethylene. The addition of such compounds acting as dispersion stabilizers in the aqueous slurry is preferably not more than 5% by weight, in particular 1% by weight to 3% by weight, based on the composition. Depending on the type or solubility of the carrier salt, the water content of the slurry can be 30% by weight to 60% by weight. The spray drying of the dispersion can be carried out in a known manner in systems provided for this purpose, so-called spray towers, using hot, co-current or counter-current drying gases. In this case, drying by drying gases carried in cocurrent with the spray material is preferred, since the loss of activity due to the potential hot air volatility of some components of the defoamer mixture can be reduced to a minimum.

The phosphate-free carrier material (I) has a granular structure and consists of water-soluble or water-dispersible, surfactant-free compounds, primarily of inorganic and / or organic salts which are suitable for use in detergents and cleaning agents. It preferably contains both alkali carbonate and alkali silicate, the latter in particular being responsible for the good storage properties of the agents according to the invention. The carrier material preferably contains 1% by weight to 50% by weight of alkali carbonate, up to 70% by weight of alkali sulfate, up to 50% by weight of alkali alumosilicate and 10% by weight to 50% by weight of alkali silicate, but can additionally contain other water-soluble or water-insoluble, water-dispersible substances. The materials which can additionally be used include, in particular, alkali metal chloride and layered silicate, for example bentonite. The alkali silicate is preferably a compound with a molar ratio of alkali oxide to SiO 2 of 1: 1.5 to 1: 3.5. The use of such silicates results in particularly good grain properties, in particular high abrasion stability and nevertheless a high rate of dissolution in water. The aluminosilicates which can be used in the carrier material for the foam regulating agents according to the invention include, in particular, the zeolites, for example zeolite NaA and NaX. Examples of suitable organic carrier materials are acetates, tartrates, citrates, succinates, carboxymethyl succinates and the alkali salts of amino polycarboxylic acids, such as NTA or EDTA, hydroxyalkane phosphonates and aminoalkane polyphosphonates, such as l-hydroxyethane-l, l diphosphonate, ethylene diaminotetramethylene phosphonate and diethylene triamine pentamethylene phosphonate. It is also possible to use water-soluble salts of polymeric or copolymeric carboxylic acids, for example polyacrylates and copolymers of acrylic acid and maleic acid. Mixtures of inorganic and organic salts can often be used with advantage. Such additional organic carrier materials are preferably not more than 20% by weight, in particular in amounts of 2% by weight to 15% by weight, in each case pulled on entire carrier material, contained in the carrier salt mixture. The preferred alkali metal in the alkali salts mentioned is sodium in all cases.

The carrier material can moreover contain film-forming polymers, for example polyethylene glycols, polyvinyl alcohols, polyvinylpyrrolidones, polyacrylates and cellulose derivatives. Usable cellulose ethers are, in particular, alkali carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose and so-called cellulose ether, such as, for example, methyl hydroxyethyl cellulose and methyl hydroxypropyl cellulose, and mixtures thereof. Mixtures of sodium carboxymethyl cellulose and methyl cellulose are preferably used, the carboxy ethyl cellulose usually having a degree of substitution of 0.5 to 0.8 carboxymethyl groups per anhydroglucose unit and the methyl cellulose having a degree of substitution of 1.2 to 2 methyl groups per Has anhydroglucose unit. The mixtures preferably contain alkali carboxymethyl cellulose and nonionic cellulose ethers in weight ratios from 80:20 to 40:60, in particular from 75:25 to 50:50. Such cellulose ether mixtures can be used in solid form or as aqueous solutions, which can be pre-swollen in the usual way. Such film-forming polymers are preferably not contained in the carrier material in excess of 5% by weight, in particular from 0.5% by weight to 2% by weight, based on the total carrier material.

In a preferred embodiment, the foam regulating agent according to the invention contains 2% by weight to 5% by weight of alkali carbonate, in particular sodium carbonate, up to 30% by weight of alkali silicate, in particular sodium silicate, 10% by weight to 75% by weight of alkali metal sulfate , in particular sodium sulfate, up to 35% by weight, in particular 10% by weight to 30% by weight of zeolite, up to 5% by weight, in particular 1% by weight to 3% by weight of water-soluble or in what ¬ this swellable polymer, in particular cellulose ether, and up to 17 wt .-%, in particular 5 wt .-% to 15 wt .-% water.

A further preferred embodiment of the foam regulating agent according to the invention contains 25% by weight to 45% by weight of alkali carbonate, 5% by weight to 20% by weight of alkali silicate, up to 50% by weight, in particular 15% by weight to 45% by weight, zeolite and / or alkali sulfate, up to 3% by weight, in particular 0.5% by weight to 2% by weight, water-soluble or water-swellable polymer and up to 20% by weight %, in particular 3% by weight to 18% by weight, water.

The foam regulating agents according to the invention are preferably free of surfactants in the mixture of substances. Surfactants are to be understood as surface-active compounds with a hydrophobic part of the molecule and hydrophilic anionic, ampholytic, zwitterionic, cationic and nonionic groups which have a cleaning or emulsifying effect in aqueous solution or dispersion. The hydrophobic part of the molecule generally consists of a hydrocarbon residue or a substituted hydrocarbon residue or a polyglycol ether residue which is poorly soluble in water, for example a polypropylene glycol or polybutylene glycol ether residue. Compounds with a non-polar molecular structure, in particular the film-forming polymers mentioned, which, under certain conditions, can likewise have a dispersing effect in water, do not fall under the definition of "surfactants".

A foam regulating agent according to the invention preferably consists of particles with particle sizes not more than 2 mm, in particular from 0.1 mm to 1.6 mm. It preferably has a bulk density in the range from 300 grams per liter to 900 grams per liter, in particular from 450 grams per liter to 800 grams per liter. It is preferably used for the production of powdered detergents or cleaning agents, a further advantage of the foam regulating agents according to the invention being their low use with good defoamer performance. It is thus possible to achieve the defoamer performance of conventional silicone defoamers with equal amounts, based on active substance, of the paraffin-based foam regulating agents according to the invention. Examples

Example 1: Production of foam regulators

By mixing together pre-swollen cellulose ether in water with a paraffin-ketone melt obtained at 130 ° C., mixing with the separately prepared aqueous slurry of sodium carbonate, sodium sulfate and optionally zeolite and / or layered silicate and subsequent mixing with the optionally used sodium silicate, the zeolite in the form of an approx. 50% by weight aqueous

Table 1: Powder composition TGew .-% l

a) Lunafleχ ( ^R ) 902, manufacturer DEA Mineralöl AG b) Stearon, manufactured in accordance with DE 2553 990 b) Behenon, manufactured in accordance with DE 2553990 d) Laundrosil ( ^R ) DGA, manufacturer Süd-Chemie e) Ratio Siθ2 to Na2θ: 3, 0 f) 80:20 mixture of Na carboxymethyl cellulose and methyl cellulose slurry and the sodium silicate was used in the form of an approximately 35% by weight water glass solution, aqueous slurries were produced from the raw materials given in Table 1, each containing about 34% by weight of water. These slurries were heated to temperatures of about 80 ° C to 90 ° C and sprayed in a drying tower, hot air (temperature 238 ° C at the entry point) being passed in cocurrent. The free-flowing powder products S1 to S6 characterized by their composition, which were free of particles larger than 2 mm in diameter, parts of particles larger than 0.8 mm of 1% by weight and particles smaller than 0.2, were obtained mm of 21 wt .-% and had a bulk density of 650 grams per liter.

Example 2

By simply mixing the amount of the foam regulator S1 according to the invention specified in the table below with conventional universal detergent base powders W1 to W3, which contained the surfactant components listed in Table 2, detergents were produced. The amounts of the foam regulators given in Table 2 were determined by washing tests (drum washing machine Miele W 717, 3.5 kg clean laundry, water hardness 3 ° d, dosage 98 g detergent) and are with regard to the foam behavior of the respective Detergent optimized under these conditions (medium foaming without foaming and without loss of liquor at 30 ° C, 40 ° C and 90 ° C). It was found that neither in S1 nor in the case of foam regulators S2 to S6 did the amount used, based on the active substance in question, of a conventional silicone-based foam inhibitor VI (used in the form of granules containing 8% by weight silicone, 35 % By weight of sodium carbonate, 41% by weight of sodium sulfate, 10% by weight of sodium silicate, 1% by weight of cellulose ether and 5% by weight of water) had to be exceeded. Table 2: Foam regulators in detergents TG% by weight active substance

a) Linear Ci2 / i5 alkyl benzene sulfonate, Na salt b) Na Ci6 / 18 alkyl sulfate

Claims

1. Homogeneous defoamer mixture, particularly suitable for adsorption onto a granular, water-soluble or water-dispersible carrier material, containing

2. defoamer mixture according to claim 1, characterized in that it 1 wt .-% to 25 wt .-%, in particular 5 wt .-% to 18 wt .-% ketone (a) and 75 wt .-% to 99 wt. -%, in particular 82 wt .-% to 95 wt .-% paraffin wax (b) contains.

3. Defoamer mixture according to claim 1 or 2, characterized in that the ketone (a) by ketonization of straight-chain or branched, saturated or unsaturated carboxylic acids or their salts with 14 to 30 C atoms, in particular 18 to 22 C atoms, or their mixtures are available.

4. defoamer mixture according to one of claims 1 to 3, characterized gekenn¬ characterized in that the paraffin wax (b) at 30 ° C a liquid fraction of less than 10 wt .-%, at 40 ° C a liquid fraction of less than 30 wt .-%, at 60 ° C a liquid fraction from 30% by weight to 60% by weight, at 80 ° C a liquid fraction from 80% by weight to 100% by weight and at 90 ° C a liquid fraction from 100% by weight having.

5. defoamer mixture according to claim 4, characterized in that the paraffin wax at 30 ° C a liquid fraction of 2 wt .-% to 5 wt .-%, at 40 ° C a liquid fraction of 5 wt .-% to 25 wt .-% , in particular from 5% by weight to 15% by weight and at 60 ° C. has a liquid content of 40% by weight to 55% by weight.

6. defoamer mixture according to one of claims 1 to 5, characterized gekenn¬ characterized in that the temperature at which a liquid content of 100 wt .-% of the paraffin wax is reached is below 85 ° C, in particular at 75 ° C to 82 ° C. .

7. Granular, free-flowing foam control agent consisting of

(I) a granular, phosphate-free, water-soluble or water-dispersible carrier material and

(II) a homogeneous defoamer mixture adsorbed thereon according to one of Claims 1 to 6, characterized in that it comprises 80% by weight to 99.5% by weight, in particular 88% by weight to 98% by weight, of carrier material (I ) and 0.5 wt .-% to 20 wt .-%, in particular 2 wt .-% to 12 wt .-% defoamer mixture (II).

8. Composition according to claim 7, characterized in that the carrier material (I) 1 wt .-% to 10 wt .-% alkali carbonate, up to 70 wt .-% Alkalisul¬ fat, up to 50 wt .-% alkali alumosilicate and 10th Contains wt .-% to 50 wt .-% alkali silicate.

9. Composition according to claim 7 or 8, characterized in that the Träger¬ material not more than 20 wt .-%, in particular 2 wt .-% to 15 wt .-% organic material, especially acetates, tartrates, citrates, succinates , Carboxymethyl succinates, alkali metal salts of aminopolycarboxylic acids, hydroxyalkane phosphonates, aminoalkane polyphosphonates, water-soluble salts of polymeric or copolymeric carboxylic acids and / or mixtures thereof.

10. Composition according to one of claims 7 to 9, characterized in that the carrier material contains not more than 5 wt.%, In particular from 0.5 wt.% To 2 wt.%, Of film-forming polymer.

11. Composition according to one of claims 7 to 10, characterized in that there are 2 wt .-% to 5 wt .-% alkali carbonate, up to 30 wt .-% alkali silicate, 10 wt .-% to 75 wt .-% % Alkali sulfate, up to 35% by weight, in particular 10% by weight to 30% by weight of zeolite, up to 5% by weight, in particular 1% by weight to 3% by weight of water-soluble or water-swellable polymer and up to 17% by weight, in particular 5% by weight to 15% by weight, of water.

12. Composition according to one of claims 7 to 10, characterized in that it contains 25 wt.% To 45 wt.% Alkali carbonate, 5 wt.% To 20 wt.% Alkali silicate, up to 50 wt. %, in particular 15% by weight to 45% by weight, zeolite and / or alkali sulfate, up to 3% by weight, in particular 0.5% by weight to 2% by weight of water-soluble or water-swellable polymer, and contains up to 20% by weight, in particular 3% by weight to 18% by weight, of water.

13. A process for the preparation of a granular foam control agent according to any one of claims 7 to 12, characterized in that in an aqueous solution or slurry of the carrier material (I) containing 30 wt .-% to 60 wt .-% water, the defoamer mixture (II), optionally with the addition of not more than 5% by weight of a water-soluble or swellable polymer, and the dispersion is spray-dried.

14. A process for the preparation of a foam regulating agent according to one of claims 7 to 12, characterized in that the granular carrier material (I) is flung in a continuous stream through the spray zone of the at least partially melted defoamer mixture (II), which is also produced continuously.

15. The method according to claim 14, characterized in that the defoamer mixture intended for adsorption on the carrier material (I) (II) by cooling a mixture of components (a) and (b) from a temperature above the melting range of (a) is generated to a temperature below it.

16. Use of a granular foam regulating agent according to any one of claims 7 to 12 for the production of powder detergents or cleaners.