EP0187257A2 - Carpet cleaning agent - Google Patents

Abstract

A carpet cleaning preparation in the form of a dry cleaning preparation in powder form which contains surfactants, organic solvents and zeolite and which is characterized in that the zeolite is in the form of a porous granulate which is unaffected by the mechanical stresses normally encountered during dry cleaning. The zeolite is preferably in the form of a porous granulate containing less than 2% by weight of particles 0.05 mm and smaller in size and less than 5% by weight of particles larger than 2 mm in size.

Description

The present invention relates to a powdery zeolite-containing agent intended for dry cleaning textiles, in particular carpets.

To clean carpets and other textile coverings on the spot, in addition to shampoos, powdered cleaning agents have recently been used which have the advantage of not leaving any edges and drying faster. Such cleaning powders contain, as essential components, surfactants and adsorbents as well as larger amounts of water in loosely bound form. The surfactants are believed to work together with the existing water to detach the dirt particles from the fibers and to transport them to the adsorbent, which is then brushed or vacuumed off with the dirt after the water has dried. A wide variety of materials have been proposed as adsorbents, for example synthetic resin foam powder (AT 296 477), fuller's earth, talc, sawdust (DE 15 19 045) and bleached wood flour (CH 461 685).

Despite the significantly smaller amounts of liquid compared to shampoos, which are applied with these powdery agents, drying times of up to several hours must also be observed with these agents, since otherwise the residues can only be removed very incompletely. This has a disadvantageous effect especially in commercial cleaning.

A sodium aluminum silicate known as zeolite has proven to be a particularly effective adsorbent both in shampoo formulations and in powdered cleaning agents. Agents on this basis, as described, for example, in German Offenlegungsschrift 25 44 605, are distinguished by a high cleaning ability. Problems arise with this material, however, from the dust nuisance and an unusually strong adhesion of the fine-particle zeolite powder to the textile fibers, which means that the cleaning agent can only be removed incompletely and the treated textiles, in particular dark-colored carpets, have a gray appearance. The proposal in European patent application EP 62 536 to add zeolite powder to a likewise insoluble carrier material, in particular cellulose powder, has not been able to make any decisive changes to these undesirable side effects. It was therefore still the task to develop dry cleaning agents for textiles with better properties overall.

The present invention offers a solution to this problem in the form of dry cleaning agents in powder form, which contain surfactants, organic solvents and zeolite, and thereby are characterized in that the zeolite is in the form of a porous granulate which is resistant to the mechanical stresses which are usual in dry cleaning.

The agents according to the invention lack the abovementioned disadvantages of the agents of the prior art, ie. they do not develop any annoying dust during use and can be removed almost completely from the textiles, so that graying does not occur. The soiling of the textiles after cleaning is unusually low. The agents are further characterized in that when they are used, normally no drying time is required between the incorporation of the powder into the textile and the removal of the powder. The finding of the solution according to the invention is particularly surprising that, despite the agglomeration of the zeolite powder to form larger, stable particles, the high cleaning performance of the agents working with finely divided zeolite is retained.

The preparation of the agents comprises two stages, namely the manufacture of the zeolite granules, which in the simplest case consists of zeolite and granulating aids, and the mixing of these granules with the other constituents of the agents. However, some or all of these constituents can be wholly or partly incorporated into the granules in the first stage, so that only the constituents remaining, in particular the organic solvents, have to be mixed with the porous granules, the liquid constituents in particular being taken up by them .

The starting material for the production of the granules are the finely divided crystalline zeolites of types A, P, X, Y and hydroxysodalite, which are in dry form or in Form aqueous suspensions, such as those obtained in the manufacture, can be used. Sodium ions are said to be predominantly present as exchangeable cations in the zeolites. Zeolite A is preferably used, which has a particularly high cleaning power and is technically easily accessible. In air-dried commercial form, it has a water content of approximately 15 to 25 percent by weight, which cannot be further reduced without the use of extreme conditions. Unless otherwise stated, data on "parts by weight" zeolite therefore include the water content of the zeolites which cannot be removed by air drying.

The content of zeolite in the finished cleaning agents is 40 to 90 percent by weight, preferably 55 to 75 percent by weight.

Zeolite granules are known from the literature in a wide variety of compositions, but are generally not suitable in this form for dry cleaning textiles. So you know from DOS 28 06 799 zeolite granules, which are produced by calcining at temperatures around 800 ° C and used to soften drinking water. Another type of zeolite granules is known for example from DAS 27 14 604, DOS 30 07 320, DOS 30 45 221 and EP-PS 21 267. The granules described there are primarily intended for use in detergents, that is, their composition has been optimized with a view to rapid disintegration of the granules in the washing water, the granulation consistently as a build-up granulation, i.e. was carried out by agglomeration of the finely divided zeolite with the aid of different additives.

Also suitable for the present invention means _Z can be obtained by buildup eolithgranulate, for example by agglomeration of zeolite powder with the help of water and granulation in a drum or a paddle mixer or in a pan granulator. Other components of the cleaning agents, such as surfactants or acids, can be incorporated into the granules. If water is used in the granulation or if the starting materials are moist, the granulation process is followed by a drying step, for which also conventional processes, such as drying in a fluidized bed at temperatures up to about 200 ° C., can be used.

A particularly preferred process for the production of suitable porous zeolite granules is the spray drying process, in which an aqueous slurry of the zeolite, the granulating aid and, if appropriate, further constituents is sprayed into droplets which then dry in an air stream when they fall down. On the one hand, this process enables aqueous starting materials to be processed without problems and, on the other hand, combines the formation of the granulate particles and their drying in one process.

In any case, the purpose of the granulation is that significantly larger particles are built up from the originally very finely divided zeolite, which have such mechanical stability that they withstand the brushing and friction stress associated with the application. Suitable granules have less than 2% by weight of particles with a size of 0.05 mm and below and less than 5% by weight of particles larger than 2 mm (determined by sieve analysis). The best performance properties are shown by granules, the individual parts of which have a diameter of over 0.2 to 1.6 mm, more than 80 percent by weight, preferably over 90 percent by weight. The mechanical stability of the granules can be determined with the aid of a simple test: in a ball vibrating mill made of porcelain, which has a content of 1 liter and is loaded with 5_project balls with a diameter of 28 mm, 100 g of the granules are run for 1 minute at 1400 revolutions per Treated for a minute, then sieved. In the case of granules suitable according to the invention, the proportion of particles with sizes up to 0.2 mm increases by no more than 15 percent by weight, preferably by no more than 5 percent by weight, in particular by no more than 2 percent by weight, based on the total weight of the granules.

Suitable granulation aids are solid, readily water-soluble organic or inorganic substances which have only a slight tendency to crystallize and are not hygroscopic. Substances which tend to polymerize, such as soluble alkali silicates, or which already have a polymeric structure, such as polymeric carboxylic acids and their salts, and soluble cellulose derivatives are particularly suitable. Water-soluble sodium silicate (water glass) and water- or alkali-soluble homo- and copolymers of acrylic acid or methacrylic acid are preferably used. Soluble sodium silicate in combination with polyacrylic acid or polymethacrylic acid is particularly preferred as the granulation aid. The amount of granulating aid, based on the total cleaning agent, is 1 to 20, preferably 5 to 20 percent by weight. Based on the Content of anhydrous zeolite, the amount of granulation aid is between 3 and 40 percent by weight, preferably between 10 and 30 percent by weight.

Suitable surfactants for the agents according to the invention are primarily nonionic and anionic surfactants. Nonionic surfactants are preferably used.

Suitable anionic surfactants are in particular those of the sulfate and sulfonate type, but other types such as soaps, long-chain N-acyl sarcosinates, salts of fatty acid cyanamides or salts of ether carboxylic acids, such as are obtainable from long-chain alkyl or alkylphenyl polyglycol ethers and chloroacetic acid, can also be used . The anionic surfactants are usually used in the form of the sodium salts.

Particularly suitable surfactants of the sulfate type are the sulfuric acid monoesters of long-chain primary alcohols of natural and synthetic origin with 10 to 20 carbon atoms, ie of fatty alcohols, such as, for example, As coconut fatty alcohols, tallow fatty alcohols, oleyl alcohol, or the C ₁₀ C ₂₀ oxo alcohols and those of secondary alcohols of these chain lengths. In addition, the sulfuric acid monoesters of the aliphatic primary alcohols, secondary alcohols or alkylphenols ethoxylated with 1 to 6 moles of ethylene oxide come into consideration. Sulfated fatty acid alkanolamides and sulfated fatty acid monoglycerides are also suitable.

The surfactants from _S ulfonattyp are primarily the salts of sulfosuccinic acid mono-and diesters containing 6 to 22 carbon atoms in the alcohol portions, alkylbenzene sulfonates containing C ₉ - C ₁₅ alkyl groups and the Esters of α-sulfo fatty acids, e.g. Are ulfonattyp example, the o (-sulfonated methyl or ethyl esters of hydrogenated coconut, palm kernel or tallow fatty Other suitable surfactants of _S the alkane sulfonates obtained from C. ₁₂ - ^C ₁₈ alkanes by sulfochlorination or sulfoxidation and subsequent hydrolysis or neutralization, or are obtainable by addition of bisulfite to olefins, and also the olefin sulfonates, which are mixtures of alkene and hydroxyalkane sulfonates and disulfonates as obtained, for example, from long-chain monoolefins with an end or internal double bond by sulfonation with gaseous sulfur trioxide and subsequent alkaline or acidic hydrolysis of the sulfonation products .

Suitable nonionic surfactants for the agents according to the invention are in particular addition products of 1 to 30, preferably 4 to 15, moles of ethylene oxide with 1 mole of a compound having 10 to 20 carbon atoms from the group of alcohols, alkylphenols, carboxylic acids and carboxamides. The addition products of ethylene oxide with long-chain primary or secondary alcohols, such as, for example, fatty alcohols or oxo alcohols, and with mono- or dialkylphenols having 6 to 14 carbon atoms in the alkyl groups are particularly important.

Furthermore, the non-ionic surfactants which can be used are the water-soluble adducts of ethylene oxide with 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups with polypropylene glycol, alkylenediamine-poly-propylene glycol and with alkylpolypropylene glycols having 1 to 10 carbon atoms in the alkyl chain, in which the polypropylene glycol chain acts as a hydrophobic radical . Also nonionic surfactants of the amine oxide, sulfoxide or alkyl glucoside type can be used, for example N-cocoalkyl-N, N-dimethylamine oxide or the condensation products of long-chain alcohols having 10 to 18 carbon atoms and glucose, and also their ethylene oxide adducts.

Particularly preferred nonionic surfactants are the reaction products of 4 to 15 moles of ethylene oxide (EO) and 1 mole of fatty alcohol with 12 to 18 carbon atoms. Typical representatives of these surfactants are tallow fatty alcohol + 5 EO, tallow fatty alcohol + 14 EO, oleyl / cetyl alcohol + 10 EO and coconut fatty alcohol + 4 EO.

The agents according to the invention contain 0.5 to 15 percent by weight, preferably 1 to 5 percent by weight. They are preferably wholly or partly in the first step of the manufacture, i.e. incorporated in the granulation of the zeolite.

The agents of the invention contain organic solvents as a further component. All solvents customary in the field of textile cleaning can be used, but solvents with boiling points above 80 ° C. from the group consisting of gasolines, alcohols, ethers and esters are preferably used. Examples of such solvents are gasoline (boiling range 140 to 200 ° C), isopropanol, isooctanol, triethylene glycol, butyl diglycol and butyl diglycol acetate. Because of their good fat-dissolving properties, petrol, isopropanol, dipropylene glycol monomethyl ether and mixtures thereof are particularly preferred. The proportion of solvent in the cleaning agent is 5 to 30, preferably 8 to 25 percent by weight. Water is contained in the agents only in such an amount as is retained by the zeolites during the production of the granules. Synthetic zeolites often contain large amounts of free alkalis, which can be recognized by the high pH of an aqueous slurry. Since many textile materials and dyes are sensitive to alkalis, acids can be added to neutralize the alkali in the preparation of the agents in order to avoid damage. Solid water-soluble organic or inorganic acids, for example amidosulfonic acid and oxalic acid, are preferred. Acidic alkali phosphates, tartaric acid, citric acid and ethylenediaminetetraacetic acid are particularly preferred because their salts, which form during neutralization, support the cleaning action of the agents. The amount of acid is determined by the alkali content of the zeolite and the desired degree of neutralization. In general, no more than 10 percent by weight of acid, based on the total composition, is used, preferably an amount which causes the zeolite granules to have a pH between 6.5 and 9 (measured on a 1% slurry in water). having.

Polymeric carboxylic acids such as polyacrylic acid and polymethacrylic acid are also suitable for neutralization. If such acids are already used as granulation aids, it is normally not necessary to add further acids.

In addition to the constituents mentioned, the cleaning agents according to the invention can also contain further active substances customary in the cleaning treatment of textiles. Examples of such active ingredients are antistatic components, optical brighteners, substances that reduce re-soiling and perfume. These components together can contain up to 10 percent by weight, preferably make up up to 5% by weight of the cleaning agents. They are preferably added to the zeolite granules with the solvent in the second step of the production process.

The cleaning of the textiles and carpets takes place in such a way that the agents of this invention are applied to the surfaces to be cleaned and are then rubbed intensively into the textiles, for example with the aid of a sponge or a brush, the dirt on the textiles being with the -Particles of detergent connects. As a rule, training times of 0.5 to 2.5 minutes, preferably 0.5 to 1.5 minutes per square meter are chosen. The residues are then removed from the textiles together with the dirt by mechanical means, for example by brushing or vacuuming. For the surface cleaning of textiles, depending on the abundance of the textiles and depending on the degree of soiling, the agents according to the invention use 20 to 200 grams per square meter, but larger quantities can also be applied in places to remove individual stains. For cleaning carpets, application rates of 50 to 150 grams per square meter are common. Although all steps of the method can be carried out manually, the preferred embodiment, in particular for carpets, is to carry out the rubbing in and, if appropriate, further steps with the aid of machines, for example combined spreading and brushing machines. The cleaning process is therefore suitable for both the household sector and for commercial use.

1. to 4. cleaning agents

1. In a drum mixer designed for laboratory use, 1.12 kg of zeolite A (sodium form, water content 18.2%, determined by drying at 800 ° C.) in powder form (particle size below 40 μm) and 124 g - powdery polymethacrylic acid (Rohagit S the company Röhm) and with constant circulation with a solution of 38 g water glass (25% in H ₂ 0, Si0 ₂ : Na ₂ 0 = 4: 1) and 14 g of a nonionic surfactant made from tallow alcohol and 14 mol EO in 700 ml tap water sprayed. After the addition had ended, the mixture was mixed for a further 10 minutes, and then the free-flowing granules formed were discharged. In order to drive off excess adhering water, the granules were dried on a tray in a drying cabinet at 80 ° C. to constant weight. A one percent slurry of this granulate in water had a pH of 8.5. The sieve analysis of the granules showed that 95% of them were in the range between 0.3 and 1.2 mm. In the stability test, the fine fraction (up to 0.2 mm) rose from 1.2% to 4.1%.

To produce the finished cleaning agent, 750 g of the dried granules were soaked with stirring with a solution of 20 g of a nonionic surfactant composed of tallow alcohol and 14 mol EO in 100 g isopropanol and 130 g butyl diglycol. The resulting detergent powder was easy to pour and free of dust.

2. In a Lödige mixer, 8.6 kg of zeolite A and 1 kg of powdered polymethacrylic acid of the same qualities as in Example 1, and 0.4 kg of polyvinylpyrrolidone (Kollidon Cl from BASF), which served as a cleaning enhancer, were introduced and kept under constant Circulation with a solution of 0.3 kg of water glass (25% in H ₂ 0, SiO ₂ : Na ₂ 0 = 4: 1) and 0.15 kg of a nonionic surfactant made from tallow alcohol and 14 moles of ethylene oxide in 5.7 kg of water sprayed. At the end of the addition, there was a water-containing granulate which was dried within 5 minutes by heating the mixer to 110 ° C. and further stirring. It showed 91% particle sizes between 0.5 and 1.5 mm in the sieve analysis. The proportion below 0.2 mm was 0.6% and rose to 3.8% in the stability test. In water, the granules had a pH of 8.9 (1%).

The granulate was further processed in an open mixing container in which it was converted into the end product by adding 25% by weight of isoprcpanol (based on the finished mixture) with slow stirring.

3. A mixture of 270 kg of a 45% aqueous suspension of zeolite Na-A (content based on anhydrous zeolite), 46 kg of water glass (37/40 Be, 34.5% aqueous solution), 18.8 kg of polymethacrylic acid, 4.0 kg of tallow alcohol with 5 moles of EO and 3.5 kg of tallow alcohol with 14 moles of EO were homogenized, heated to 65 ° C. and injected into the upper end of a spray tower. The drying was carried out in countercurrent with air at an inlet temperature between 150 ° C and 180 ° C. In this way, a granulate was obtained, the sieve 98.2% analysis consisted of particles with sizes between 0.2 and 1.6 mm, 0.2% fine parts under 0.05 mm and 0.5% parts over 2 mm in diameter. In the stability test, the proportion of particles with sizes up to 0.2 mm rose from 9.6% to 10.8%.

To produce the finished cleaning agent, 170 kg of dry granulate were mixed in a mixing container with 30 kg of gasoline (Isopar G). A white, dry-feeling, free-flowing product formed.

4. This cleaning agent was produced from the same zeolite granulate as the agent from Example 3. However, 20 kg of a mixture of 50 percent by weight of gasoline (Isopar G, boiling point 165 ° C.) and 50 percent by weight of n-propanol were added to each 80 kg of the granules.

5. to 6. Cleaning agents according to the prior art

5. According to DOS 25 44 605 Example 21, a powdered carpet cleaner of zeolite powder, which was loaded with coconut fatty acid diethanolamide, okosalkoholsulfat by mixing with _K and manufactured Isoprcpanol was. The product mainly consisted of very fine powder fractions less than 0.05 mm in diameter; in addition, loose agglomerates up to 5 mm in size were still present after stirring. In the stability test, the product disintegrated completely into particles less than 0.2 mm in diameter.

6. According to EP-OS 62 536, Example 1, a powdered carpet cleaning agent was made from cellulose fiber, zeolite powder, calcium carbonate, propylene glycol methyl ether and water. It was a flaky, slightly sticky product with no hard granules.

7. Cleaning effect, dust pollution and re-soiling

The usage properties of the cleaning agents were examined on naturally soiled beige colored polyamide velor carpets. For this purpose, a long runner was divided into several segments, each of which was sprinkled evenly with one of the cleaning agents 1 to 6 in amounts of 70 g per square meter. Immediately after the detergents had been dispensed, they were worked into the carpet using a 40 kg single-pane cleaning machine with a rotating brush, which is customary in the commercial sector, for about 45 seconds per square meter. Only with the agent according to EP 62 536, as stated there, was an experiment carried out without brushing in. After the sufficient time for drying, the carpet segments were cleaned with detergents and adhering dirt for about 1 minute per square meter as far as possible. After the cleaning result had been assessed, the runner was released for use again and the re-soiling was assessed after 3 weeks.

The evaluation of the performance properties was carried out by 5 examiners who had to give grades between 1 (excellent) and 6 (very poor). The average values from the _E inzelnoten are summarized in Table 1 below.

8. Graying

To determine this property, dark red polyamide velor carpets that were not soiled were treated with the cleaning agents as in Example 7. The graying was then determined visually by comparison with untreated pieces of carpet and evaluated using a point scale (1 = no graying, 5 = very strong graying). The results are shown in the last column of Table 1.

Claims (14)

1. Dry cleaning agent in powder form for textiles, containing surfactants, organic solvents and zeolite, characterized in that the zeolite is present together with granulating aid in the form of a porous granulate which is resistant to the mechanical stresses customary in dry cleaning. 2. Dry cleaning agent according to claim 1, characterized in that a type A zeolite is used which contains sodium ions as exchangeable cations. 3. Dry cleaning agent according to one of claims 1 or 2, characterized in that the zeolite granules are produced by spray drying an aqueous preparation of zeolite powder, granulating aid and optionally other active ingredients of the cleaning agent. 4. Dry cleaning agent according to one of claims 1 to 3, characterized in that more than 80 percent by weight of the granules consist of particles with diameters of over 0.2 to 1.6 mm. 5. Dry cleaning agent according to one of claims 1 to 4, characterized in that the zeolite before or during the production of the granules with the aid of an acid to a pH between 6.5 and 9 (measured on a 1% slurry of the granules in Water) is brought. 6. Dry cleaning agent according to one of claims 1 to 5, characterized in that it consists of 40 to 90 percent by weight zeolite, 0.5 to 15 weight percent surfactant, 5 to 30 percent by weight organic solvent, 1 to 20 percent by weight of granulation aids, 0 to 10 percent by weight of solid, water-soluble acid and 0 to 10 percent by weight of other common ingredients
consists. 7. Dry cleaning agent according to one of claims 1 to 6, characterized in that the surfactant contained from the group of addition compounds of 1 to 30 moles of ethylene oxide to long-chain primary or secondary alcohols with 10 to 20 C atoms or to alkylphenols with 6 to 14 C -Atoms in the alkyl groups and their mixtures is selected. 8. Dry cleaning agent according to one of claims 1 to 7, characterized in that the organic solvent has a boiling point above 80 ° C and is selected from the group consisting of gasolines, alcohols, ethers, esters and mixtures thereof. 9. Dry cleaning agent according to one of claims 1 to 8, characterized in that the granulating aid is selected from the group of water-soluble alkali silicates, water-soluble polymeric carboxylic acids and their salts, water-soluble cellulose derivatives and mixtures thereof. 10. Dry cleaning agent according to one of claims 1 to 9, characterized in that it was produced from a zeolite granulate by mixing with a solution of surfactant or optionally further components in an organic solvent and from 55 to 75 percent by weight of zeolite Na-A, 1 to 5 weight percent addition product from 4 to 15 mol EO of fatty alcohols with 12 to 18 carbon atoms, 8 to 25 percent by weight of organic solvent from the group of dipropylene glycol monomethyl ether, gasoline, isopropanol and mixtures thereof, 5 to 20 percent by weight of granulating aid in the form of a combination of water-soluble sodium silicate and polyacrylic acid or polymethacrylic acid and 0 to 5 percent by weight of other common ingredients
consists. 11. A process for producing a powdery dry cleaning agent for textiles, which consists in converting zeolite powder with the aid of a granulating aid into a porous granulate which is resistant to the mechanical stresses that are usual in dry cleaning, and adding these granules with organic solvent and, if appropriate, further active ingredients loaded. 12. The method according to claim 11, characterized in that the zeolite granules are produced by spray drying an aqueous preparation from zeolite powder, granulating aid and optionally other active ingredients of the cleaning agent. 13. A method of cleaning textiles, in particular carpets, characterized in that a dry cleaning agent according to one of claims 1 to 10 is applied to the textile in amounts of 20 to 200 grams per square meter and 0.5 to 2.5 minutes per square meter in the textile is rubbed in intensively, whereby dirt and cleaning agents combine, and the residues are then mechanically removed from the textile. 14. A method for cleaning carpets according to claim ₁₃ , characterized in that the rubbing in of the agent and optionally further steps of the method are carried out with the aid of devices or machines, 50 to 150 grams of detergent are used per square meter and the duration of the rubbing in , 5 to 1.5 minutes per square meter.