EP1572850B1 - Cleaner for hard surfaces - Google Patents

Abstract

Cleaner for hard surfaces, especially glass. Application of the cleaner containing a colloidal silica sol results in a modification of the streaming potential of the surface by −5 to −50 mV. The cleaner can be used to hydrophilize and clean hard surfaces by contact.

Description

The invention relates to aqueous liquid surface-active cleaning agents for hard surfaces, in particular glass, which contain a colloidal silica sol and by the application of which the negative charge of the surface is increased.

The cleaning of hard surfaces and in particular the cleaning of glass has in addition to the hygienic aspect also an aesthetic side. Thus, it is desirable that a cleaned surface dries as quickly and uniformly as possible in order to avoid the formation of unsightly drop or strip residues ("noses") wherever possible. However, these can not only after cleaning, especially when using hard water, arise, but also between the cleaning operations when the surface comes into contact with water again, so-called. Rain effect. This is the case, for example, in bathrooms, but especially in exposed to the weather surfaces such as windows, etc. Therefore, the fast drying of the surfaces is generally desirable. Furthermore, it is advantageous if the surface is wetted flat over a longer period, instead of the film tearing, which also leads to "noses". The surface wetting with a thin film also contributes to rapid drying; In addition, tiny particles of dirt are distributed evenly, instead of concentrated in the "nose" occur, so that the surface looks optically cleaner. Another aspect, again especially in areas exposed to weathering, is the reduction in the tendency of cleaned surfaces to become soiled, since it is desirable for the consumer to allow as long a period as possible to pass between two cleaning operations without the surface becoming dirty to the viewer. In addition, an anti-fog effect is desirable to minimize the condensation of water on the surface. To meet all these requirements, the cleaner should modify the surface to be cleaned such that the wetting behavior changes from an untreated surface so that it becomes less quickly soiled and dries quickly without the formation of "noses".

The European application EP 1 215 276 (Clariant ) describes detergents and cleaners which contain microdisperse silicate-containing particles. These may also be colloidal silica sols. These particles are said to act as a surface coating agent and result in improved soil release while reducing redetachment. About a further change of the surface condition or via an Antiregen- / Antifogging effect no statement is made.

The DE 199 52 383 A1 (Henkel ) also describes detergents and cleaners which can impart temporary stain-resistant properties to a surface to be cleaned by the particles contained with a particle size of 5 to 500 nm. Among other things, SiO ₂ sols can be used as particles here. The nanoscale particles lead to an increase in the wettability of the substrates to be cleaned. Also in this case, no further statement is made on a further change in the surface condition as on a possible anti-rain or anti-fog effect.

Subject of the publication DE 100 21 726 A1 (Henkel ) is the use of nanoscale particles to improve soil release and / or reduce the re-fouling of especially textile, but also hard surfaces. The particles used may again be SiO ₂ sols. The particles cause an increase in the hydrophilicity of the surface and a structuring of the surface, the latter point is not further explained. Further changes of the surface condition are just as little described as a possible anti-rain or anti-fog effect.

In the patent application US 2002/0045010 A1 (Procter & Gamble) finally describes agents that contain a nanoparticle system and can be used for surface modification on all hard surfaces. The surface modification may, inter alia, produce one or more of the following properties: wetting, filming, rapid drying, uniform drying, soil release, self-cleaning, less staining, reduction in re-fouling, cleaner appearance, improved gloss, etc. The surface is wholly or partially treated with the agent partially coated. After drying, in air or by heating, etc., and / or curing, the surface is permanently or at least modified for a longer period of time.

Thus, the prior art already knows some means that can solve some of the problems addressed. However, it is desirable to modify by means of a cleaning agent a surface to be cleaned in such a way that on the one hand, the network and flow behavior of water changes such that a flat, quick-drying Film is created, which does not tear when drying and tends to form "noses". On the other hand, the tendency to re-soiling and fogging should be reduced.

The object of the present invention is therefore to provide a cleaning agent for hard surfaces, in particular glass, through which the surface to be cleaned is wetted flat surface and dries quickly and has a low tendency to misting and Wiederanschmutzen.

It has been found that detergents to which certain colloidal nanoparticulate silica sols are added cause a change in the flow potential of the cleaned surface to more negative values and that surfaces wetted with such agents are wetted flat, uniformly drying without the formation of "noses" and fog or pollute less quickly.

The invention therefore relates to a cleaning agent for hard surfaces, in particular glass, containing a colloidal nanoparticulate silica sol having a particle size of 1 to 100 nm, characterized in that the flow potential of the surface changes by -5 to -50 mV by its application and the mean microroughness of the surface is increased by at least 5 nm to a maximum of 30 nm, compared to an untreated surface.

The use of these cleaning agents preferably results in a hydrophilization of the surface, which leads to a long-lasting wettability of the surface as a flat film. As a result, the dirt particles are evenly distributed and do not form "noses", so that the appearance of the cleaned surface over a longer period of time is clean. These effects, as well as the lower tendency to repellency and the anti-fogging effect, are preferably observed over an extended period of time after the application of the agent, for example for three weeks. However, a permanent equipment of the surface is not sought. Finally, the detergent to be used should meet the usual technical and aesthetic requirements for a hard surface cleaner; In particular, the agent should be transparent in a preferred embodiment and also suitable for spraying and have a good cleaning performance.

Colloidal nanoparticulate silica sols for the purposes of this invention are stable dispersions of amorphous particulate silicon dioxide SiO ₂ having particle sizes in the range from 1 to 100 nm. The particle sizes are preferably in the range from 3 to 50 nm, particularly preferably from 4 to 40 nm a silica sol which is suitable in the sense to be used with this invention which is sold under the trade name Bindzil ^® 30/360 available from Akzo silica sol having a particle size of 9 nm. Further suitable silica sols are Bindzil ^® 15/500, 30/220, 40/200 257/360 (Akzo), Nyacol ^® 215, 830, 1430, 2034DI and Nyacol ^® DP5820, DP5480, DP5540 etc. (Nyacol Products), Levasil ^® 100/30, 100F / 30, 100S / 30, 200/30, 200F / 30, 300F / 30, VP 4038, VP 4055 (HC Starck / Bayer) or CAB-O-SPERSE ^® PG 001, PG 002 (aqueous dispersion of CAB-O-SIL ^®, Cabot), Quartron PL-1 , PL-3 (Fuso Chemical Co.), Köstrosol 0830, 1030, 1430 (Chemiewerk Bad Köstritz).

The silica sols used may also be surface-modified silica treated with sodium aluminate (alumina-modified silica).

However, not every colloidal silica sol is suitable as an additive according to the invention. It has been found that only those silica sols in the context of the invention can be used, the application of which increases the average micro-roughness by at least 5 nm to a maximum of 30 nm and a change in the flow potential by at least -5 mV to a maximum of -50 mV on the cleaned surface, respectively, compared with an untreated surface. Microroughness is a quantity known to those skilled in the art and measurable by atomic force microscopy (AFM). It indicates the distance deviation from an ideally smooth surface and is measured in μm or nm.

Furthermore, it has been found to be advantageous if the hydrophilizing particles are adsorbed on the surface in such a way that the surface is covered to 10 to 75%, thus at least 25% free surface should remain.

The agent according to the invention can furthermore also contain surface-active substances. Suitable surface-active substances for the agents according to the invention are surfactants, in particular from the classes of anionic and nonionic surfactants. Preferably, the compositions contain anionic surfactants. The amount of anionic surfactant is usually not more than 10 wt .-%, preferably between 0.01 and 5 wt .-%, in particular between 0.01 and 1 wt .-%, for example 0.5 wt .-%. If the compositions contain nonionic surfactants, their concentration is usually not more than 3% by weight, preferably between 0.001 and 0.3% by weight and in particular between 0.001 and 0.1% by weight. In a preferred embodiment, however, the agent according to the invention is free of nonionic surfactants. It has proved to be particularly advantageous furthermore proven when the total surfactant content in the ready-to-use composition is not more than 6% by weight. If the agent is offered as a concentrate for dilution before use, the total surfactant content is preferably not more than 15 wt .-%, particularly preferably 1 to 12 wt .-%, in particular 2 to 10 wt .-%.

Suitable anionic surfactants are preferably C ₈ -C ₁₈ -alkylbenzenesulfonates, in particular having about 12 C atoms in the alkyl moiety, C ₈ -C ₂₀ -alkanesulfonates, C ₈ -C ₁₈ -monoalkyl sulfates, C ₈ -C ₁₈ -alkylpolyglycol ether sulfates having 2 to 6 ethylene oxide units (EO) in the ether part as well as sulfosuccinic mono- and di-C ₈ -C ₁₈ -alkyl esters. Furthermore, C ₈ -C ₁₈ -α-olefinsulfonates, sulfonated C ₈ -C ₁₈ -fatty acids, in particular dodecylbenzenesulfonate, C ₈ -C ₂₂ -Carbonsäureamidethersulfate, C ₈ -C ₁₈ -Alkylpolyglykolethercarboxylate, C ₈ -C ₁₈ -N-Acyltauride , C ₈ -C ₁₈ -N sarcosinates and C ₈ -C ₁₈ -alkyl isethionates or mixtures thereof.

The anionic surfactants are preferably used as sodium salts, but may also be present as other alkali metal or alkaline earth metal salts, for example magnesium salts, and in the form of ammonium or mono-, di-, tri- or tetraalkylammonium salts, in the case of the sulfonates also in the form their corresponding acid, eg Dodecylbenzenesulfonic.

Examples of such surfactants are sodium cocoalkyl sulfate, sodium sec-alkanesulfonate having about 15 carbon atoms and sodium dioctylsulfosuccinate. Fatty alkyl sulfates and fatty alkyl + 2EO ether sulfates having 12 to 14 C atoms have proven to be particularly suitable.

C ₈ -C ₁₈ -alcohol polyglycol ethers, ie ethoxylated and / or propoxylated alcohols having 8 to 18 C atoms in the alkyl moiety and 2 to 15 ethylene oxide (EO) and / or propylene oxide units (PO), C ₈ - are especially nonionic surfactants. C ₁₈ -carboxylic acid polyglycol esters having 2 to 15 EO, for example tallow fatty acid + 6-EO esters, ethoxylated fatty acid amides having 12 to 18 C atoms in the fatty acid part and 2 to 8 EO, long-chain amine oxides having 14 to 20 C atoms and long-chain alkylpolyglycosides with 8 to mention 14 carbon atoms in the alkyl moiety and 1 to 3 glycoside units. Examples of such surfactants are oleyl-cetyl-alcohol with 5 EO, nonylphenol with 10 EO, lauric acid diethanolamide, Kokosalkyldimethylaminoxid and Kokosalkylpolyglucosid with an average of 1.4 glucose units. Particular preference is given to fatty alcohol polyglycol ethers having in particular 2 to 8 EO, for example C _12-14 -fatty alcohol + 4-EO ether.

C ₈ -C ₁₈ alkyl alcohol polypropylene glycol / polyethylene glycol ethers are preferred known nonionic surfactants. They can be described by the formula I, RO- (CH ₂ CH (CH ₃ ) O) _p (CH ₂ CH ₂ O) _e -H, in which R ^{i is} a linear or branched, aliphatic alkyl and / or alkenyl radical having 8 to 18 carbon atoms, p is 0 or numbers from 1 to 3 and e is numbers from 1 to 20.

The C ₈ -C ₁₈ -alkyl alcohol polyglycol ethers of the formula I are then obtained by addition of propylene oxide and / or ethylene oxide to alkyl alcohols, preferably to fatty alcohols. Typical examples are polyglycol ethers of the formula I in which R ^{i is} an alkyl radical having 8 to 18 carbon atoms, p is 0 to 2 and e is a number from 2 to 7. Preferred representatives are, for example, C ₁₀ -C ₁₄ fatty alcohol + 1PO + 6EO ether ( p = 1, e = 6) and C ₁₂ -C ₁₈ fatty alcohol + 7EO ether ( p = 0, e = 7) and mixtures thereof ,

It is also possible to use end-capped C ₈ -C ₁₈ -alkyl alcohol polyglycol ethers, ie compounds in which the free OH group in the formula I has been etherified. The end-capped C ₈ -C ₁₈ -alkyl alcohol polyglycol ethers can be obtained by relevant methods of preparative organic chemistry. Preferably, C ₈ -C ₁₈ alkyl alcohol polyglycol ethers are reacted in the presence of bases with alkyl halides, in particular butyl or benzyl chloride. Typical examples are mixed ethers of the formula I in which R ^{i is} a technical fatty alcohol radical, preferably C _12/14 cocoalkyl radical, p is 0 and e is 5 to 10, which are closed with a butyl group.

Preferred nonionic surfactants are furthermore alkyl polyglycosides (APG) of the formula II, R ⁱⁱ O [G] _x , in which R ^{ii is} a linear or branched, saturated or unsaturated alkyl radical having 8 to 22 carbon atoms, [G] is a glycosidically linked sugar radical and x represent a number from 1 to 10. APG are nonionic surfactants and are known substances that can be obtained by the relevant methods of preparative organic chemistry. The index number x in the general formula II indicates the degree of oligomerization (DP degree), ie the distribution of mono- and oligoglycosides, and stands for a number between 1 and 10. While x in a given compound must always be integer and here before For all given values x = 1 to 6, the value x for a given alkyl glycoside is an analytically determined arithmetic variable, which usually represents a fractional number. Preferably, alkyl glycosides having a mean degree of oligomerization x of 1.1 to 3.0 are used. From an application point of view, those alkyl glycosides whose degree of oligomerization is less than 1.7 are preferred and especially between 1.2 and 1.6. The glycosidic sugar used is preferably xylose, but especially glucose.

The alkyl or alkenyl radical R ⁱⁱ (formula II) can be derived from primary alcohols having 8 to 18, preferably 8 to 14, carbon atoms. Typical examples are caproic alcohol, caprylic alcohol, capric alcohol and undecyl alcohol, and technical mixtures thereof, such as those obtained during the hydrogenation of technical fatty acid methyl esters or in the hydrogenation of aldehydes from ROELEN's oxosynthesis.

Preferably, however, the alkyl or alkenyl radical R ⁱⁱ is derived from lauryl alcohol, myristyl alcohol, cetyl alcohol, palmoleyl alcohol, stearyl alcohol, isostearyl alcohol or oleyl alcohol. Also to be mentioned are elaidyl alcohol, petroselinyl alcohol, arachidyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol and technical mixtures thereof.

As other nonionic surfactants, nitrogen-containing surfactants may be contained, e.g. Fatty acid polyhydroxyamides, for example glucamides, and ethoxylates of alkylamines, vicinal diols and / or carboxylic acid amides having alkyl groups having 10 to 22 carbon atoms, preferably 12 to 18 carbon atoms. The degree of ethoxylation of these compounds is generally between 1 and 20, preferably between 3 and 10. Preferred are ethanolamide derivatives of alkanoic acids having 8 to 22 carbon atoms, preferably 12 to 16 carbon atoms. Particularly useful compounds include the lauric, myristic and palmitic monoethanolamides.

Also particularly preferred are agents which contain anionic and nonionic surfactant, in particular combinations of fatty alkyl sulfates and / or fatty alcohol polyglycol ether sulfates with fatty alcohol polyglycol ethers.

In addition to the previously mentioned types of surfactant, the agent according to the invention may also contain cationic surfactants and / or amphoteric surfactants.

Suitable amphoteric surfactants are, for example, betaines of the formula (R ⁱⁱⁱ ) (R ^iv ) (R ^v ) N ⁺ CH ₂ COO ^- , in which R ^{iii is} an alkyl radical optionally interrupted by hetero atoms or heteroatom groups having 8 to 25, preferably 10 to 21 carbon atoms and R ^iv and R ^{v are} identical or different alkyl radicals having 1 to 3 carbon atoms, in particular C ₁₀ -C ₁₈ alkyl dimethylcarboxymethylbetain and C ₁₁ -C ₁₇ -Alkylamidopropyl dimethylcarboxymethyl betaine. The compositions contain amphoteric surfactants in amounts, based on the composition, of 0 to 10 wt .-%.

Suitable cationic surfactants include the quaternary ammonium compounds of the formula (R ^vi ) (R ^vii (R ^viii ) (R ^ix ) N ⁺ X ^- , in which R ^vi to R ^{ix are} four identical or different, in particular two long and two short-chain , Alkyl radicals and X ^{- are} an anion, in particular a halide ion, for example didecyl-dimethyl-ammonium chloride, alkylbenzyl-didecyl-ammonium chloride and mixtures thereof The compositions contain cationic surfactants in amounts, based on the composition, from 0 to 10 wt .-%.

In a particularly preferred embodiment, however, the agent contains as surfactant components only one or more anionic surfactants, preferably C ₈ -C ₁₈ -alkyl sulfates and / or C ₈ -C ₁₈ -alkyl ether sulfates, and / or one or more nonionic surfactants.

Furthermore, the cleaning agents according to the invention may contain water-soluble organic solvents, for example lower alcohols and / or ether alcohols, but preferably mixtures of different alcohols and / or ether alcohols. Lower alcohols in the context of this invention are straight-chain or branched C _1-6 -alcohols. The amount of organic solvent is usually not more than 50% by weight, preferably 0.1 to 30% by weight, more preferably 0.5 to 15% by weight, most preferably 1 to 10% by weight.

The alcohols used are in particular ethanol, isopropanol and n-propanol. As ether alcohols are sufficiently water-soluble compounds having up to 10 carbon atoms in the molecule into consideration. Examples of such ether alcohols are ethylene glycol monobutyl ether, propylene glycol monobutyl ether, diethylene glycol monobutyl ether, propylene glycol monotertiary butyl ether and propylene glycol monoethyl ether, of which in turn ethylene glycol monobutyl ether and propylene glycol monobutyl ether are preferred. If alcohol and ether alcohol are used side by side, the weight ratio of both is preferably between 1: 2 and 4: 1. On the other hand, if mixtures of two different ether alcohols, in particular ethylene glycol monobutyl ether and propylene glycol monobutyl ether, are used, the weight ratio of both is preferably between 1: 6 and 6: 1 , in particular between 1: 5 and 5: 1, for example at 4: 1, wherein preferably the proportion of ether alcohol having fewer carbon atoms is the higher of the two.

Furthermore, the agents according to the invention may contain volatile alkali. As such, ammonia and / or alkanolamines containing up to 9 carbon atoms in the molecule can, used. As alkanolamines, the ethanolamines are preferred and of these in turn the monoethanolamine. The content of ammonia and / or alkanolamine is preferably 0.01 to 3 wt .-%, in particular 0.02 to 1 wt .-%, particularly preferably 0.05 to 0.75 wt .-%.

Alkaline agents may additionally contain carboxylic acid in addition to the volatile alkali, wherein the equivalent ratio of amine and / or ammonia to carboxylic acid is preferably between 1: 0.9 and 1: 0.1. Suitable carboxylic acids having up to 6 carbon atoms, which may be mono-, di- or polycarboxylic acids. Depending on the equivalent weight of amine and carboxylic acid, the content of carboxylic acid is preferably between 0.01 and 2.7% by weight, in particular between 0.01 and 0.9% by weight. Examples of suitable carboxylic acids are acetic acid, glycolic acid, lactic acid, citric acid, succinic acid, adipic acid, malic acid, tartaric acid and gluconic acid, of which preferably acetic acid, citric acid and lactic acid are used. Particular preference is given to using acetic acid.

Acid detergents according to the invention may also contain acids instead of volatile alkali. Suitable acids are, in particular, organic acids such as the abovementioned carboxylic acids acetic acid, citric acid, glycolic acid, lactic acid, succinic acid, adipic acid, malic acid, tartaric acid and gluconic acid or amidosulfonic acid. In addition, however, it is also possible to use the mineral acids hydrochloric acid, sulfuric acid and nitric acid or mixtures thereof. Particular preference is given to acids selected from the group comprising amidosulfonic acid, citric acid and formic acid. They are preferably used in amounts of 0.1 to 5 wt .-%, more preferably 0.5 to 4 wt .-%, in particular 1 to 3 wt .-%.

In addition, the acidic cleaning agents according to the invention may also contain small amounts of bases. Preferred bases are selected from the group of alkali and alkaline earth metal hydroxides and carbonates, in particular the alkali metal hydroxides, of which potassium hydroxide and especially sodium hydroxide is particularly preferred. In the acidic agents, bases are used in amounts of not more than 1% by weight, preferably 0.01 to 0.1% by weight.

The composition preferably has a viscosity according to Brookfield (model DV-II +, spindle 31, rotational frequency 20 min ^-1 , 20 ° C) of 0.1 to 200 mPa · s, in particular 0.5 to 100 mPa · s, most preferably 1 up to 60 mPa · s, on. For this purpose, the agent may viscosity regulators contain. The amount of viscosity regulator is usually up to 0.5 wt .-%, preferably 0.001 to 0.3 wt .-%, in particular 0.01 to 0.2 wt .-%, most preferably 0.05 to 0.15 wt .-%.

Suitable viscosity regulators are, for example, organic natural thickeners (agar-agar, carrageenan, tragacanth, gum arabic, alginates, pectins, polyoses, guar flour, locust bean gum, starch, dextrins, gelatin, casein), organic modified natural products (carboxymethylcellulose and other cellulose ethers, hydroxyethyl - and -propylcellulose and the like, core flour ethers), organic fully synthetic thickeners (polyacrylic and polymethacrylic compounds, vinyl polymers, polycarboxylic acids, polyethers, polyimines, polyamides) and inorganic thickeners (polysilicic acids, clay minerals such as montmorillonites, zeolites, silicas).

Examples of polyacrylic and polymethacrylic compounds include the high molecular weight homopolymers of acrylic acid crosslinked with a polyalkenyl polyether, in particular an allyl ether of sucrose, pentaerythritol or propylene (INCI name according to the International Dictionary of Cosmetic Ingredients of The Cosmetic, Toiletry, and Fragrance Association (US Pat. CTFA): carbomers), also referred to as carboxyvinyl polymers. Such polyacrylic acids are obtainable inter alia from Fa. 3V Sigma under the tradename Polygel ^® such as Polygel ^® DA, and by the company. BFGoodrich under the tradename Carbopol ^®, such as Carbopol ^® 940 (molecular weight about 4,000,000), Carbopol ^® 941 (molecular weight approximately 1,250,000) or Carbopol ^® 934 (molecular weight approximately 3,000,000). Furthermore, the following acrylic acid copolymers are included: (i) Copolymers of two or more monomers from the group of acrylic acid, methacrylic acid and their simple ester, preferably formed with C _1-4 -alkanols ( INCI acrylates copolymer), such as the copolymers of methacrylic acid, butyl acrylate and methyl methacrylate (CAS name according to Chemical Abstracts service: 25035-69-2) or of butyl acrylate and methyl methacrylate (CAS 25852-37-3) and, for example, by the company Rohm & Haas under the trade names Aculyn ^®. and Acusol ^®, and from Degussa (Goldschmidt) under the trade name Tego ^® polymers are available, for example the anionic non-associative polymers Aculyn ^® 22, Aculyn ^® 28, Aculyn ^® 33 (crosslinked), Acusol ^® 810, Acusol ^® 823 and Acusol ^® 830 (CAS 25852-37-3); (ii) crosslinked high molecular weight acrylic acid copolymers, such as those crosslinked with an allyl ether of sucrose or pentaerythritol copolymers of C _10-30 alkyl acrylates with one or more monomers from the group of acrylic acid, methacrylic acid and their simple, preferably formed with C _1-4 alkanols, esters (INCI Acrylates / C10-30 Alkyl Acrylate crosspolymer) and which are obtainable for example from the company. BFGoodrich under the tradename Carbopol ^®, Carbopol ^® example hydrophobized ETD 2623 Carbopol ^® 1382 and (INCI acrylates / C10-30 alkyl acrylate Crosspolymer) and Carbopol AQUA ^® 30 (formerly Carbopol ^® EX 473). In the international application WO 97/38076 there is listed a series of polymers derived from acrylic acid which are suitable viscosity regulators.

Further thickeners are the polysaccharides and heteropolysaccharides, in particular the polysaccharide gums, for example gum arabic, agar, alginates, carrageenans and their salts, guar, guar gum, tragacanth, gellan, Ramzan, dextran or xanthan and their derivatives, for example propoxylated guar, and also their mixtures. Other polysaccharide thickeners, such as starches or cellulose derivatives, may alternatively or preferably be used in addition to a polysaccharide gum, for example starches of various origins and starch derivatives, for example hydroxyethyl starch, starch phosphate esters or starch acetates, or carboxymethylcellulose or its sodium salt, methyl, ethyl, hydroxyethyl, Hydroxypropyl, hydroxypropylmethyl or hydroxyethyl methylcellulose or cellulose acetate. A particularly preferred polysaccharide thickener is the microbial anionic heteropolysaccharide xanthan gum, which is produced from Xanthomonas campestris and some other species under aerobic conditions with a molecular weight of 2-15 × 10 ^6, and for example, by Fa. Kelco under the trade names Keltrol ^® and Kelzan ^® or from Rhodia is available under the trade name Rhodopol ^®.

As thickeners, it is also possible to use phyllosilicates. These include, for example, available under the trade name Laponite ^® magnesium or sodium-magnesium phyllosilicates from Solvay Alkali, in particular the Laponite ^® RD or Laponite ^® RDS, and the magnesium silicates Süd-Chemie, especially the Optigel ^® SH.

When selecting the appropriate viscosity regulator, care must be taken to preserve the transparent appearance of the detergent, i. the use of the thickening agent should not lead to clouding of the agent.

In one embodiment, the cleaning agent according to the invention can also be formulated as a higher-viscosity liquid. The viscosity is then between 200 and 1000 mPa · s (Brookfield viscometer DV-II +, small sample adapter). The content of viscosity regulator (thickener) can be up to 2 wt .-% in these cases.

In addition to the components mentioned, the compositions according to the invention may contain other auxiliaries and additives, as are customary in such compositions. These include in particular dyes, perfume oils, preservatives, complexing agents for alkaline earth metal ions, enzymes, bleaching systems and antistatic agents. Furthermore, in particular, copolymers such as those available from BASF Sokalan® ^®, such as the Sokalan CP ^® 9, the sodium salt of a maleic acid-olefin copolymer can be used for surface modification of polymers.

The amount of such additives is usually not more than 2 wt .-% in the detergent. The lower limit of the use depends on the nature of the additive and can be up to 0.001 wt .-% and below, for example, in the case of dyes. Preferably, the amount of excipients is between 0.01 and 1 wt .-%.

The pH of the compositions according to the invention can be varied over a wide range, but is preferably in the range from 2.5 to 12. Glass cleaner formulations and all-purpose cleaners in particular have a pH of from 6 to 11, more preferably from 7 to 10.5 and bath cleaners in particular a pH of 2 to 5, most preferably from 2.5 to 4.0.

The agents according to the invention are preferably formulated ready for use. A formulation as concentrate to be diluted prior to use is likewise possible within the scope of the teaching according to the invention, the contents then being contained in the upper range of the respectively indicated quantitative ranges.

The compositions of the invention can be prepared by mixing directly from their raw materials, then mixing and final standing of the agent to freedom from bubbles.

The compositions of the invention are preferably used for glass cleaning, both for windows and for mirrors and other glasses. But they can also be used to clean hard surfaces, especially those surfaces that are occasionally or often over-flushed with dirty or even clean water, such as showers, bathtubs, and bathroom or kitchen surfaces. A further field of use of agents according to the invention are rinse aids for dishwashers. But textile surfaces can also undergo hydrophilization by the use of agents according to the invention. Yet another area of application is the hydrophilization of automotive surfaces, both car paints and car windows. The agents according to the invention can of course also be used for paints in general, and also metal surfaces can be hydrophilated with them.

Examples

The alkaline glass cleaners E1 to E3 according to the invention and the alkaline comparative agent V1 and the acidic bath cleaners E4 to E6 according to the invention and the acidic comparison agent V2 were prepared by simply stirring the components together according to Tables 1 and 2 . E1 to E3 and E4 to E6 contained the nanoparticulate silica sol according to the invention, while V1 and V2 had no additive. All funds were clear and colorless.

The following raw materials were used in the examples: Fatty alcohol sulfate sodium salt: Sodium lauryl sulfate (Texapon ^®) LS 35, Cognis) Fatty alcohol ether sulfate sodium salt: Sodium laureth sulfate (Texapon ^®) N70, Cognis) Hydroxyethylcellulase: Natrosol HHBR (Hercules) Nanoparticulate silica sol: Alkaline cleaners: Bindzil ^® 30/360 (Akzo) acidic cleaner: Bindzil ^® CAT 80 (Akzo) <b> Table 1: alkaline glass cleaners </ b> Composition [% by weight] E1 E2 E3 V1 Fatty alcohol sulfate sodium salt 0.5 0.5 0.5 0.5 ethanol 3 3 3 3 Monoethanolamine 0.5 - 0.2 - ammonia - 0.3 0.2 0.3 Nanoparticulate silica sol 0.2 0.2 0.2 - Perfume 0.01 0.01 0.01 0.01 acetic acid - 0.02 0.05 0.02 water ad 100 ad 100 ad 100 ad 100

With these glass cleaners window panes were cleaned and then exposed to the weather over two weeks. Slices which had been treated with the cleaners E1 to E3 according to the invention showed, even after two weeks wetting with water, the formation of a spreading, flat film. Residue formation took place in the form of very finely divided particles, so that the disc looks optically clean.

On the other hand, the disc treated with the comparator V1 showed, just like an untreated glass pane, the formation of droplets after just two days on wetting with water. The residue formation took place in the form of "noses", so that the disc appeared contaminated. <b> Table 2: Acid Bath Cleaner </ b> Composition [% by weight] E4 E5 E6 V2 Fatty alcohol sulfate sodium salt 0.5 0.5 0.5 0.5 ethanol 3 3 3 3 citric acid 1 1 3 1 EDTA - 0.2 - - Nanoparticulate silica sol 0.2 0.2 0.2 - Perfume 0.01 0.01 0.01 0.01 caustic soda - 0.02 0.05 0.02 water ad 100 ad 100 ad 100 ad 100

Bathroom tiles were cleaned with these cleaners. Thereafter, the tiles were sprayed once a day with water (15 ° dH) for two weeks. The treated with the inventive compositions E4 to E6 tiles have also demonstrated after two weeks when wetted with water, the formation of a-spreading, sheet-like film. Residue formation took place in the form of extremely finely divided particles, so that the tiles had a visually clean appearance.

On the other hand, the tiles treated with the comparison agent V2 , as well as untreated tiles, already after two days when wetted with water showed the formation of drops. Residue formation took the form of "noses", so that the tiles appeared soiled.

Testing of anti-fogging and anti-rain effect

The glass cleaners E1 to E3 and the comparison agent V1 were then examined for their anti-fogging and anti-rain effect:

First, 2 ml of the respective composition with a folded fleece total size 20 cm × 20 cm ( Chicopee, Duralace 60) were distributed on a mirror of size 30 cm × 60 cm and polished out in practice. After 30 minutes, a second identical treatment was carried out in each case. Another 30 minutes later, the anti-fog and anti-rain effects were tested as follows.

Anti-fog effect. The treated mirror was held for 5 seconds over a dish (28 cm x 50 cm x 4 cm) with 1.5 liters of boiling water and immediately evaluated for whether and, if so, how much the mirror was fogged.

Anti-rain effect. About 10 g of test rain, prepared from tap water and 8 g / l wfk carpet pigment soil (55% by weight kaolin, 43% by weight quartz, 1.5% by weight flame black 101 , 0.5% by weight iron oxide black, wfk code wfk -09 W) of the wfk -Testgewebe GmbH (http://www.wfk.de), evenly sprayed on the pretreated mirror surface. Wetting was immediately followed by wetting and dripping and, after drying, dirt distribution and staining.

The evaluation was done visually by a panel of five persons, each person assigning the four means the positions 1 to 4 in the order of decreasing effect. The respective mean value, together with a rating in Table 3, is given as a grade. The lower the grade, the better the effect. <b> Table </ b> 3 effect grade evaluation composition Anti-fogging effect E1 3 little effect E2 2 good protection against fogging E3 1 very good effect V1 4 no anti-fog effect Anti-rain effect Overall impression of the wet disc E1 2.4 good wetting, few drops E2 1.8 very good wetting, hardly any drops E3 1.6 very good wetting, no drops V1 4.0 good wetting, breaks fast Anti-rain effect Overall impression of the dry disc E1 2.8 slightly better dirt distribution than V1 E2 1.8 Dirt evenly distributed, hardly any stains E3 1.6 Dirt evenly distributed, no stains V1 4.0 Partly stains and "traces of wear", dirt even in the upper part evenly

The means E1 to E3 show in contrast to V1 both an anti-rain effect and an anti-fog effect.

Analogous to the invention. Means E1 to E3 were also prepared the comparison means V3 to V5 with the known as anti-rain additive polymer poly (sodium p-styrene sulfonate) according to Table 4 based on V1 as a frame formulation. These alkaline agents were clear as well as colorless. <b> Table 4 </ b> Additive [% by weight] V3 V4 V5 Poly (sodium p-styrenesulfonate), 70,000 g / mol 0.1 0.2 0.4

As described above, the means V3 to V5 were also tested for an anti-fogging effect.

In contrast to the agents E1 to E3 according to the invention, however, the agents V3 to V5 did not exhibit an anti-fogging effect.

Comparative tests

Several attempts have been made to delineate inventively employable silica sols which can not be used according to the invention. On the one hand, microroughness and flow potentials as well as contact angles (with respect to water and ethylene glycol) of surfaces treated with different additives were measured, but also investigations on the flow behavior and the long-term efficacy were carried out. In each case, an identical glass cleaner base was used and added the specified amount of the respective additive.

1. Surface roughness (micro roughness)

The surface roughness on the micrometer level was measured by means of an atomic force microscope (AFM, Nanoscope III). For this purpose, a white test tile (Villeroy & Boch WC ceramic) was cleaned with the aid of Pril solution and then ethanol, sprayed with a 1% solution of the respective additive in a glass cleaner base and dry-rubbed the wet tile with the aid of a cellulose cloth. The treated tile was measured in the AFM.

The following result was obtained: average micro-roughness [nm] before coating after coating Additive 1 (Bindzil 30/360) 10 17 Additive 2 (Bindzil CAT 80) 6 28 Additive 3 * (Nanogate LSraB 0212) 9 12 Additive 4 * (Klebosol 20 H 12) 8th 11 Additive 5 * (Klebosol 30 N 12) 6 9 Additive 6 * (Klebosol 30 R 12) 9 10 * not according to the invention

The increase in micro-roughness causes parallel to the hydrophilization easier soil removal. The micro-roughness should accordingly increase by at least 5 nm to a maximum of 30 nm in order to achieve the desired hydrophilizing effect. Increasing the roughness by only 3 nm is not sufficient. With an increase of more than 30 nm, no residues and stripes are guaranteed.

2. Flow potential

The flow potential of treated tiles was measured using an EKA device (Anton Paar ElectroKinetics Analyzer). For this purpose, a white test tile (Villeroy & Boch WC ceramic) was cleaned with the aid of Pril solution and then ethanol, sprayed with a 1% solution of the respective additive in a glass cleaner base and dry-rubbed the wet tile with the aid of a cellulose cloth. The thus treated tile was measured in the EKA device at 200 mbar and with 0.001 mol KCl as the electrolyte.

The following result was obtained: Flow potential [mV] after coating uncoated tile -32 Additive 1 (Bindzil 30/360) -61 Additive 2 (Bindzil CAT 80) -48 Additive 3 * (Nanogate LSraB 0212) -23 Additive 4 * (Klebosol 20 H 12) -34 Additive 5 * (Klebosol 30 N 12) -36 Additive 6 * (Klebosol 30 R 12) -28 * not according to the invention

The change of the negative flow potential proves the hydrophilization due to the increased amount of surface charge. The flow potential should therefore change by at least -5 mV to a maximum of -50 mV in order to achieve the desired hydrophilizing effect. A change in the flow potential by less than -5 mV does not cause sufficient hydrophilization. With a change above -50 mV, the surface energy is increased so much that the tendency to re-soiling increases. This is also the case, for example, with colloidal TiO ₂ particles.

3. Flow behavior

A black standard test tile (Villeroy & Boch bath ceramic, 18x12 cm) is sprayed with the respective test product. The moist tile is rubbed dry with the help of a cellulose cloth. Subsequently, the tile is completely immersed in Moistened with demineralised water and then placed in a vertical position. The drying tile is filmed via camcorder. Using digital image processing, the dry area is calculated as a percentage of the area of the tile. Thus, the temporal course of the drying can be followed.

The following result was obtained: Time [min], until 90% area 95% area are dried 1. (glass cleaner base) 10.8 12.0 2. (Base with 0.6% Bindzil 30/360 + N) 10.0 10.9 3. (base with 2% Nanogate LSraB 0212) 9.3 9.9 4. (Base with 0.6% Bindzil 30/360) 8.7 9.2 5. (base with 0.3% Bindzil 30/360) 7.9 8.4 (N = nonionic surfactant: end capped fatty alcohol alkoxylate)

The flow behavior with the addition of Bindzil 30/360 leads to the best result at lower concentrations. The shorter drying time leads to a directly visible advantage for the consumer.

4. Long-term effectiveness

The various formulations already used in the runtime test are applied to freestanding window surfaces of 1x2 m size, which are exposed to the weather. An expert panel of 5 persons examines the cleanliness impression of the panes daily. Grades from 1 (no pollution) to 6 (heavy pollution) are awarded. Over the days, the average values of the notes give a statement about their durability. Time in days 1 2 3 5 10 15 20 25 Rez. 1 1 1.4 1.6 2.2 3.0 4.2 5.2 5.4 Rez. 2 1 1.2 1.4 1.8 2.4 3.6 4.2 4.8 Rez. 3 1 1.2 1.4 2.0 2.6 3.6 4.4 4.8 Rez. 4 1 1.4 1.4 1.6 1.8 3.0 3.8 4.2 Rec. 5 1 1.2 1.6 1.6 2.0 3.2 4.0 4.4

5. Contact angle

The contact angle of treated tiles with water and ethylene glycol was measured by means of drop contour analysis (contact angle measuring device Krüss DSA 10). For this purpose, a white test tile (Villeroy & Boch WC ceramic) was cleaned with the aid of Pril solution and then ethanol, sprayed with a 1% solution of the respective additive in a glass cleaner base and dry-rubbed the wet tile with the aid of a cellulose cloth. The contact angle of water or ethylene glycol on the thus treated tile was determined.

The following result was obtained: Contact angle [°] against H ₂ O against ethylene glycol uncoated tile 33 7 Additive 1 (Bindzil 30/360) 10 18 Additive 2 (Bindzil CAT 80) 14 14 Additive 3 (Nanogate LSraB 0212) 8th 11

The lowering of the contact angle to water and the simultaneous increase in the contact angle with respect to ethylene glycol proves the hydrophilization of the surface. The non-inventive nanogate additive 3 increases the contact angle with respect to ethylene glycol insufficient.

The contact angle should therefore be lower than that of water by at least 15 ° in order to achieve the desired hydrophilizing effect. The contact angle with ethylene glycol, on the other hand, should be increased by at least 5 °.

The measurements of the microroughness and the flow potentials already prove that not every silica sol is suitable for use according to the invention in cleaning agents for the hydrophilization of surfaces. Furthermore, a surface coverage of 10 to 75% is advantageous, i. even after adsorption of the hydrophilicizing particles at least 25% free surface should remain. By contrast, the silica sol from Nanogate (additive 3, LSraB 0212) achieved a coverage of more than 90%. The measurement of the coverage was carried out with the aid of an atomic force microscope (AFM, Nanoscope III) and optical image evaluation.

Another criterion is the incorporation into a colorless, translucent, stable product. Some commercially available silica sols can not meet this criterion. For example, the adhesive types 30 H 25 and 30 V 25 to be obtained from Clariant are opaque in the product. Like the Baykisol 30 available from Bayer, the Klebosol 30 V 50 is a white slurry which is opaque in the product and does not allow a stable formulation. The font mentioned in the introduction EP 1 215 276 used colloidal silica sols are therefore not suitable for use according to the invention. The same applies to that in the also cited German application DE 100 21 726 This silica sol from Merck, which corresponds to the Syton HT-50 from DuPont: This colloidal silica with a particle size of 40 nm is also opaque in the product.

The following three examples of concentrates to be diluted before use are also according to the invention. The agent should preferably be diluted in the ratio 1: 1 to 1: 100 with water; particularly preferred is a dilution in the ratio 1:10. <b> Table 5: Glass Concentrate Concentrate </ b> Composition [% by weight] E7 E8 E9 Fatty alcohol sulfate 8.00 8.00 8.00 fatty alcohol ether sulfate 2.00 2.00 2.00 hydroxyethyl 0.30 0.30 0.30 Sodium hydroxide 45% 0.05 0.05 0.05 dye 0,008 0,008 0,008 Perfume 0,070 0,070 0,070 ethanol 5.00 5.00 5.00 Nano Part. Silica sol 30% 3.0 2.0 1.0 Water, demin. 81.57 82.57 83.57 pH 10.5 10.5 10.5 Viscosity [mPas] 150 150 150

Claims (18)

1. A transparent cleaning agent for hard surfaces, in particular glass, containing a nanoparticulate colloidal silica sol with a particle size from 1 to 100 nm, characterized in that by its application, the flow potential of the surface, measured with an EKA apparatus (Anton Paar ElektroKinetikAnalyser) at 200 mbars and with 0.001 moles of KCI as an electrolyte, is changed by -5 to -50 mV and the average microroughness of the surface, measured by means of a atomic force microscope (AFM; Nanoscope III), is increased by at least 5 nm to a maximum of 30 nm, as compared with an untreated surface.
2. The cleaning agent according to claim 1, characterized in that the silica sol preferably has a particle size from 3 to 50 nm, in particular from 4 to 40 nm, for example 9 nm.
3. The cleaning agent according to any of claims 1 and 2, characterized in that, by its application, the surface is hydrophilicized.
4. The cleaning agent according to any of the preceding claims, characterized in that it causes improved dirt removal behavior and/or lower future soiling.
5. The cleaning agent according to any of the preceding claims, characterized in that it causes fast and uniform drying of a surface after renewed watering.
6. The cleaning agent according to any of the preceding claims, characterized in that it has an anti-fogging effect and an anti-watering effect.
7. The cleaning agent according to any of the preceding claims, characterized in that it contains anionic and/or non-ionic surfactants.
8. The cleaning agent according to any of the preceding claims, characterized in that it contains one or more anionic surfactants, preferably selected from the group comprising C₈-C₁₈ alkylbenzenesulfonates, C₈-C₂₀ alkanesulfonates, C₈-C₁₈ fatty alcohol sulfates, C₈-C₁₈ alkylpolyglycolethersulfates, sulfosuccinic acid mono-and di-(C₈-C₁₈ alkyl)esters as well as mixtures thereof, more preferably sodium salts of fatty alcohol sulfates.
9. The cleaning agent according to any of the preceding claims, characterized in that it contains non-ionic surfactants, preferably selected from the group comprising C₈-C₁₈ alcoholpolyglycolethers, C₈-C₁₈ carboxylic acid polyglycol esters, ethoxylated fatty acid amides, C₁₄-C₂₀ aminoxides and alkylpolyglycosides as well as mixtures thereof.
10. The cleaning agent according to any of the preceding claims, characterized in that it contains at least one water-soluble organic solvent, preferably selected from the group comprising lower alcohols, ether alcohols, as well as mixtures thereof.
11. The cleaning agent according to any of the preceding claims, characterized in that it contains at least one volatile alkali, preferably selected from the group comprising ammonia, alkanolamines with up to 9 C atoms as well as mixtures thereof.
12. The cleaning agent according to any of the preceding claims, characterized in that it contains at least one carboxylic acid, preferably selected from the group comprising acetic acid, glycolic acid, lactic acid, citric acid, succinic acid, adipic acid, malic acid, tartaric acid, gluconic acid as well as mixtures thereof.
13. The cleaning agent according to any of the preceding claims, characterized in that it contains one or more viscosity regulators, preferably selected from the group comprising organic natural thickeners, organic modified natural substances, organic fully synthetic thickeners and inorganic thickeners.
14. The cleaning agent according to any of the preceding claims, characterized in that it contains one or more further customary adjuvants and additives in cleaning agents, preferably selected from the group comprising dyes, perfume oils, preservatives, complexing agents for earth alkaline ions, enzymes, bleaching systems and anti-static substances.
15. The cleaning agent according to any of the preceding claims, characterized in that it has a viscosity from 0.1 to 200 mPa.s, in particular 0.5 to 100 mPa.s, most preferably 1 to 60 mPa.s (Brookfield model DV-II+, spindle 31, 20 min^-1, 20°C).
16. The cleaning agent according to any of the preceding claims, characterized in that it has a pH value from 2.5 to 12.
17. A method for hydrophilicizing hard surfaces by bringing into contact the surface with an agent according to claims 1 to 17.
18. The use of an agent according to claims 1 to 17 for cleaning hard surfaces, in particular glass.