EP4048741A1

EP4048741A1 - Preservative-free dispersion paint

Info

Publication number: EP4048741A1
Application number: EP20797088.0A
Authority: EP
Inventors: Ingo Hörsting; Georg Bender
Original assignee: Brillux GmbH and Co KG
Current assignee: Brillux GmbH and Co KG
Priority date: 2019-10-23
Filing date: 2020-10-23
Publication date: 2022-08-31
Also published as: WO2021078932A1; DE102019128640A1

Abstract

The present invention relates to a dispersion paint which contains the following components, in each case in relation to the total weight of the dispersion paint: 5 to 75 % by weight of pigment and/or filler, 1 to 30 % by weight of binder, selected from the group consisting of poly(meth)acrylate, poly(meth)acrylate copolymer with a (meth)acrylate fraction of at least 25 % by weight in relation to the total weight of the copolymer, poly(meth)acrylate terpolymer with a (meth)acrylate fraction of at least 25 % by weight in relation to the total weight of the terpolymer, polystyrene, polystyrene copolymer with a styrene fraction of at least 25 % by weight in relation to the total weight of the copolymer, and mixtures thereof, 0.05 to 10 % by weight of amino acid, 0.01 to 7 % by weight of alkali adjusters, and 20 to 60 % by weight of water, the amino acid comprising at least one amino group and each amino group of the amino acid having a pKs value of from 9.0 to 10.0, and the pH of the dispersion paint being from 10 to 13. The dispersion paint has outstanding storage stability and also excellent flow properties.

Description

Preservative-free emulsion paint

The present invention relates to an emulsion paint, a method for producing the emulsion paint and the use of the emulsion paint.

Plastic emulsion paints, also known as emulsion paints, are of major economic and technical importance. They usually contain relatively large amounts of organic chemical components, in particular synthetic resins such as polymers, especially in the form of synthetic resin dispersions. In order to ensure adequate storage stability, emulsion paints usually require preservatives, in particular biocides such as isothiazolines. However, conventional preservatives such as isothiazolines are allergens that can cause irritation and irritation to the skin in allergy sufferers. As a result, the use of conventional preservatives in emulsion paints is subject to ever more stringent legal restrictions.

To overcome this problem, different preservative-free systems for emulsion paints have already been developed. These systems are usually based on water glass and alkyl siliconates. However, preservative-free systems based on pH buffer systems have also been developed for preservative-free emulsion paints.

A particular challenge when using additives to stabilize emulsion paints is that the additives should only have as little influence as possible on the processability and flow properties of the emulsion paint. However, it has been found that many of the additives which can be used to stabilize the emulsion paint and to protect it from microbial attack have a negative effect on the processability and / or the flow properties of the emulsion paint. EP 1 297079 B1 describes, for example, an emulsion paint containing polymer dispersion, pigment and / or filler, water glass and water. This emulsion paint is characterized by the fact that it does not require any preservatives. However, due to the presence of water glass, an inorganic binder is also contained, which can impair the properties of the emulsion paint, in particular its processability.

EP 3 460010 A1 describes a composition for forming coatings on buildings and the like, which has a content of a buffer system based on phosphate or based on at least one organic amino compound, the content being between 0.01% by weight and 20% by weight of phosphate or phosphate Amino compound in each case based on the total weight of the composition, at least one pKa value of the acid of the buffer system being between 9 and 14. However, EP 3 460 010 A1 does not solve the problem of impaired processability and / or impaired flow properties.

The present invention thus has the object of providing a preservative-free emulsion paint which has excellent processability and / or excellent flow properties. At the same time, the preservative-free emulsion paint should have a high shelf life and good environmental compatibility.

A further object of the invention is to provide a preservative-free emulsion paint which can be produced inexpensively and / or from easily available materials. Furthermore, the preservative-free emulsion paint should meet regulatory requirements and / or be able to be handled with common painting utensils without unusual safety precautions. All or some of these objects are achieved according to the invention by the emulsion paint according to claim 1, the method according to claim 16 and the use according to claim 18.

Advantageous embodiments of the invention are specified in the dependent claims and are explained in detail below.

The emulsion paint according to the invention has a pH of 10 to 13 and, based in each case on the total weight of the emulsion paint, contains a. 5 to 75% by weight pigment and / or filler, b. 1 to 30% by weight of binder, selected from the group consisting of poly (meth) acylate, poly (meth) acylate copolymer with a (meth) acylate content of at least 25% by weight, based on the total weight of the copolymer, poly (meth) acrylate terpolymer with a (meth) acrylate content of at least

25% by weight, based on the total weight of the terpolymer, polystyrene, polystyrene copolymer with a styrene content of at least 25% by weight, based on the total weight of the copolymer and mixtures thereof, c. 0.05 to 10% by weight amino acid, i.e. 0.01 to 7% by weight of alkali plates and e. 20 to 60% by weight of water, the amino acid comprising at least one amino group and each amino group of the amino acid having a pK a value of 9.0 to 10.0.

Surprisingly, it has been found that the emulsion paint according to the invention has a high storage stability even without preservatives and at the same time can be processed very well. In particular, the emulsion paint according to the invention has excellent flow properties. The components contained in the emulsion paint have excellent compatibility with one another, as a result of which surfaces which are coated with the emulsion paint according to the invention have a uniform and visually appealing appearance. Both the pH value and the flow properties of the Emulsion paints according to the invention remain essentially constant even after a storage time of several weeks, in particular several months.

The emulsion paint according to the invention is also inexpensive and can be produced from readily available materials and can be applied to surfaces in a simple manner using common painting utensils.

Without wishing to be bound by any particular theory, the excellent processability and the excellent flow properties combined with high storage stability of the emulsion paint appear to be due to the interaction of the alkali plate with the amino acid and the binder in the emulsion paint. It has been found that the combination of an amino acid in which each amino group of the amino acid has a pK a value of 9.0 to 10.0 and a binder selected from the group consisting of poly (meth) acylate, poly ( meth) acylate copolymer with a (meth) acylate proportion of at least 25% by weight, based on the total weight of the copolymer, poly (meth) acylate terpolymer with a (meth) acrylate proportion of at least 25% by weight, based Based on the total weight of the terpolymer, polystyrene, polystyrene copolymer with a styrene content of at least 25% by weight, based on the total weight of the copolymer and mixtures thereof, at the same time enables excellent pH stabilization and particularly good rheological properties and good applicability has the consequence. This particular interaction between amino acid and binder was not evident from the prior art.

The amino acid in the emulsion paint according to the invention leads, on the one hand, to a stabilization of the pH value, as a result of which the emulsion paint is effectively protected against microbial attack for many weeks. On the other hand, the amino acid is in combination with a binder selected from the group consisting of poly (meth) acylate, poly (meth) acylate copolymer with a (meth) acylate content of at least 25% by weight, based on the Total weight of the copolymer, poly (meth) acrylate terpolymer with a (meth) acrylate content of at least 25% by weight, based on the total weight of the terpolymer, polystyrene, polystyrene copolymer with a styrene content of at least 25% by weight, based on the total weight of the copolymer and mixtures thereof, also for the good processability and the excellent flow properties of the emulsion paint responsible.

The amino acid of the emulsion paint according to the invention comprises at least one amino group, each amino group of the amino acid having a pKa value in the range from 9.0 to 10.0. The emulsion paint preferably has several amino acids of the type mentioned, e.g. in the form of a mixture of two or more amino acids. The one or more amino acids in the emulsion paint can be α-amino acids, β-amino acids, γ-amino acids, d-amino acids or any other amino acids, α-amino acids being particularly preferred for reasons of cost.

Whenever "any amino group" is mentioned here or elsewhere, this means any functional group that has an NR3, NHR2 or NH2R functionality, where each R independently of one another can in principle stand for all different residual groups, in particular for hydrogen, Alkyl, alkenyl, alkynyl, cycloalkyl, haloalkyl, heterocycloalkyl, ether, ester, aryl, heteroaryl, arylalkyl, halogen, amino, hydroxy, thiol, thioether, nitrile , Ketone, carboxy and peroxy groups. The term “amino group” for the purposes of the invention also includes amide or guanidine groups. Thus, for example, the amino acid arginine has several amino groups within the meaning of the invention, of which only one amino group fulfills the requirement that the pK a value is in the range from 9.0 to 10.0. The guanidine functionality has a pKa value of 12.48. Thus, arginine does not meet the requirement within the meaning of the invention that every amino group of the amino acid has a pK a value of 9.0 to 10.0.

If the “pK value” of the amino groups of the amino acids is mentioned here or elsewhere, the pK value for the protonated one is specific Amino group meant, ie for the reaction NR3 + H ⁺ <-> NHR ₃ ⁺ . The pKs value is the negative decadic logarithm of the equilibrium constant for this equilibrium reaction. The pKa value here relates to the pKa value under standard conditions which are known to the person skilled in the art. In particular, the pKa value relates to the pKa value of the amino acid at 25 ° C. (298 K) in an aqueous solution at an amino acid concentration of 0.1 to 1.0 mol / L.

Methods for determining the equilibrium constant or the pKa value are known to the person skilled in the art. For example, the equilibrium constant or the pKa value can be determined by means of half-titration by pH measurement. For weak acids, the law of mass action implies pH = pKs at the half-equivalence point. The half-equivalence point is the point at which half of a certain amount of acid has been neutralized with the corresponding amount of base that would have led to complete neutralization. For the half titration, for example, a concentration of 1 mol / L and a temperature of 23 to 25 ° C for the titration can be selected. Bases which can be used for such a half titration are known to the person skilled in the art. For example, the half titration can be carried out with sodium hydroxide and / or potassium hydroxide. An indicator electrode, for example a pH electrode, can be used to determine the pH value of the solution, which measures the changes in potential in the solution in combination with such a potentiometric measurement or, independently of this, an indicator can also be used to determine the pH value. pH indicators are known to the person skilled in the art, for example litmus, for example in the form of litmus paper, bromothymol blue, thymol blue, phenolphthalein, methyl red or mixtures thereof, for example in the form of universal indicators, can be used for this.

It has surprisingly been found that amino acids in which each amino group has a pKa value in the range from 9.0 to 10.0 are outstandingly suitable for stabilizing the pH value of a preservative-free emulsion paint. Emulsion paints that contain such an amino acid have a long-lasting buffer effect, which means that the emulsion paint is protected against microbial attack for a particularly long time. In addition, the combination of the amino acid with the binder of the emulsion paint according to the invention gives a coating agent with excellent flow and processing properties.

If, on the other hand, at least one amino group of the amino acid has a pKa value higher than 10.0, it is difficult to achieve an optimal balance between pH value or pH value. To maintain pH stability and excellent flow and processing properties of the paint.

If only small amounts of an amino acid with at least one amino group with a pKa value of more than 10.0 are used, the flow and processing properties of the paint are still intact, but the buffering effect of the solution is only limited and the storage stability of the paint is consequently inadequate . If, on the other hand, larger amounts of an amino acid with at least one amino group with a pKa value of more than 10.0 are used, the buffering effect of the solution is sufficient, but the flow and processing properties of the paint deteriorate significantly.

If, on the other hand, at least one amino group of the amino acid has a pKa value lower than 9.0, the buffer effect is inadequate and the color is not adequately protected against microbial attack.

Surprisingly, these problems do not arise with an amino acid in which each amino group of the amino acid has a pK a value of 9.0 to 10.0.

It has been shown that a good buffer effect is achieved particularly effectively and at the same time inexpensively if the amino acid is selected from the group consisting of alanine, glycine, leucine, isoleucine, valine, serine, threonine and mixtures thereof. It has been found in particular that emulsion paints with the said neutral, acyclic a-amino acids can be processed particularly well and have particularly good rheological properties.

The amino acid in the emulsion paint according to the invention is even more preferably selected from alanine, glycine, leucine, isoleucine, valine and mixtures thereof. The amino acids mentioned have no further functional groups apart from the carboxyl and amino groups. It has surprisingly been found that such relatively simple amino acids with the alkali plate and the binder result in a particularly uniform coating agent in the emulsion paint according to the invention. Without wishing to be bound by any particular theory, the simple chemical structure of these amino acids seems to be an advantage, since there are only minimal interfering interactions between the components in the color.

It has also been found that, from the group of amino acids mentioned, alanine and / or glycine, preferably glycine, lead to particularly good rheological properties and particularly good applicability of the emulsion paint.

In principle, the proportion of amino acid in the emulsion paint according to the invention can be from 0.05 to 10% by weight. If the amount of amino acid in the emulsion paint is less than 0.05% by weight, long-term pH stabilization can no longer be guaranteed and the storage stability of the emulsion paint deteriorates considerably. If the amount of amino acid in the emulsion paint is more than 10% by weight, however, the rheological properties of the emulsion paint deteriorate significantly. A particularly good ratio of high storage stability and excellent rheological properties can be achieved if the emulsion paint is from 0.1 to 7% by weight, preferably from 0.2 to 5% by weight, preferably from 0.3 to 2.5% by weight. %, more preferably from 0.4 to 2.0% by weight or particularly preferably from 0.5 to 1.5% by weight, based on the total weight of the emulsion paint, amino acid. While the amino acid ensures that the pH value remains stable for many weeks, the alkaline plate ensures the original setting of the pH value, so that the emulsion paint is well protected against microbial attack. If the proportion of alkali metal in the emulsion paint is less than 0.01% by weight, however, this protection can no longer be guaranteed. If the proportion of alkali metal is more than 7% by weight, on the other hand, there is a significant deterioration in the flow properties of the emulsion paint and increased safety requirements are necessary for handling the emulsion paint. Consequently, the emulsion paint according to the invention contains 0.01 to 7% by weight of alkali plates, based on the total weight of the emulsion paint. It has been found here that particularly good storage stability and excellent handling of the emulsion paint can be ensured if the emulsion paint is from 0.02 to 4% by weight, preferably from 0.05 to 3% by weight, preferably from 0.2 to 2% by weight or particularly preferably from 0.4 to 1.5% by weight, based on the total weight of the emulsion paint, contains alkali plates.

Unless explicitly stated otherwise, all percentages by weight are based on the dry weight of the compound. If, for example, a 50% (m / m) aqueous KOH solution is used as the alkali plate, only the KOH solids content is used to calculate the proportion of alkali plate in the emulsion paint. A proportion of 1% by weight of KOH in the emulsion paint consequently means that 2% by weight of a 50% strength aqueous KOH solution was used. The same applies, for example, to aqueous dispersions of binder polymers or aqueous dispersions of pigments.

In principle, very different alkali plates can be used to adjust the pH value. However, for economic and practical reasons, alkali plates have been selected from the group consisting of alkali hydroxides such as potassium, sodium and / or lithium hydroxide, alkaline earth hydroxides such as magnesium, calcium and / or barium hydroxide, ammonium hydroxide, xonotlite and / or ettringite proved to be particularly suitable. Sodium hydroxide and / or potassium hydroxide is particularly suitable as an alkali plate for the precise adjustment of the pH value of the emulsion paint.

For the special properties of the emulsion paint according to the invention, the interplay between binder, amino acid, alkali plate and pH value is of particular importance. The binder plays an important role here, because it has to be stable at high pH values, at the same time it has to give the emulsion paint a good structure and bind all components well when it hardens on the wall. For this purpose, the emulsion paint according to the invention contains 1 to 30% by weight of a binder selected from the group consisting of poly (meth) acrylate, poly (meth) acrylate copolymer with a (meth) acrylate content of at least 25% by weight. %, based on the total weight of the copolymer, poly (meth) acrylate terpolymer with a (meth) acrylate content of at least 25% by weight, based on the total weight of the terpolymer, polystyrene, polystyrene copolymer with a styrene content of at least 25% by weight, based on the total weight of the copolymer and mixtures thereof. These binders meet all of the requirements mentioned.

It has been found that the emulsion paint has particularly good flow properties, excellent abrasion resistance and effective integration of all components of the emulsion paint during curing if the binder is a poly (meth) acrylate copolymer with a (meth) acrylate content of at least 25 % By weight, based on the total weight of the copolymer. It is particularly preferred here if the poly (meth) acrylate copolymer has a (meth) acrylate content of at least 40% by weight, preferably at least 50% by weight, based on the total weight of the copolymer. Such copolymers have proven to be particularly stable at high pH values. The proportion of binder in the emulsion paint is from 1 to 30% by weight, based on the total weight of the emulsion paint. The emulsion paint has particularly good flow properties and particularly high abrasion resistance when the emulsion paint contains from 2 to 25% by weight, preferably from 3 to 20% by weight or particularly preferably from 4 to 15% by weight, of binder.

The emulsion paint according to the invention contains 5 to 75% by weight of pigment and / or filler. Various substances can be used as pigments here. The pigment is preferably selected from the group consisting of titanium dioxide, iron oxide yellow, allyide (monoazo), bismuth vanadate, (di) arylides, azo condensation pigments, pyranthones, isoindolines, anthraquinones, derivatives of dioxazines, perinones, naphthol-AS derivatives, perylenes, quinacridones , Indanthrene, phthalocyanine, rutile-tin-zinc, quinacridone, diketopyrrolo-pyrrole, iron oxide red, phthalocyanine blue, dioxazine, cobalt blue, ultramarine blue, phthalocyanine green, chromium oxide green, cobalt green, carbon black, iron oxide black, pyrazolo-quinazopigone, monolithic naphthol Pigment Violet 23, and mixtures thereof.

The proportion of pigment in the emulsion paint can vary within wide limits. This depends on the one hand on the desired color of the emulsion paint and on the other hand with the color strength of the pigment. Preferred ranges of amounts of pigment in the emulsion paint are from 1 to 40% by weight, preferably from 5 to 30% by weight or particularly preferably from 10 to 25% by weight, based on the total weight of the emulsion paint, pigment.

Inorganic pigments are usually used in larger quantities than organic pigments. According to a preferred embodiment, the emulsion paint contains from 15 to 50% by weight of an inorganic pigment, preferably from 20 to 40% by weight of an inorganic pigment. According to a further preferred embodiment, the emulsion paint contains from 1 to 35% by weight, preferably from 1 to 20% by weight, of an organic pigment. According to another preferred In the embodiment, the emulsion paint contains from 15 to 50% by weight, preferably from 20 to 40% by weight, of an inorganic pigment and from 1 to 20% by weight, preferably from 1 to 10% by weight, of an organic pigment.

In one embodiment, preference is given to using inorganic pigments. Examples of inorganic pigments are oxides such as titanium dioxide, iron oxides, e.g. P.Y. 42, P.R. 101, P.Bk. 11, chrome oxide green, e.g. P.G. 17, chromium oxides, e.g. P.Br. 29, mixed phase pigments e.g. cobalt oxide blue P.B. 28 and Green P.G. 50, bismuth vanadate P.Y. 184, rutile-tin-zinc P.O. 216, rutile-tin-zinc-titanium P.Y. 213, silicates, e.g., ultramarine blue P.B. 29 and carbon, e.g. carbon black P.Bk. 7th

According to a further embodiment, preference is given to using organic pigments. Examples of organic pigments are azo pigments, e.g. Alylidgelb (Monoazo) P.Y. 74, polycyclic pigments, e.g., quinacridones P.R. 122, Perinone P.O. 43, pyrazolo-quinazolone P.O. 67, diketo-pyrrolo-pyrrole (DPP) P.R. 254, Dioxazine P.V. 23 and metal complex pigments, e.g. copper phthalocyanine blue P.B. 15: 3 and Green P.G. 7th

The names of the inorganic and organic pigments used for the examples correspond to the Generic Names of the Color Index of the British Society of Dyers and Colourists.

According to a further embodiment, mixtures of inorganic and organic pigments are used.

By using the pigments listed, colored emulsion paints can be produced which essentially cover the entire color spectrum.

According to a further preferred embodiment of the invention, the emulsion paint contains from 5 to 65% by weight, preferably from 15 to 55% by weight or particularly preferably from 25 to 45% by weight, based on the total weight of the Emulsion paint, filler. With this amount of filler in the emulsion paint, a good appearance and, at the same time, good applicability is guaranteed. In addition, emulsion paints can be produced inexpensively with these amounts of filler.

Common fillers for emulsion paints are known to the person skilled in the art. In principle, all fillers known to the person skilled in the art are suitable for the emulsion paint according to the invention. However, it has proven to be particularly advantageous for the application and abrasion properties of the emulsion paint if the filler is selected from the group consisting of dolomite, barium sulfate, feldspar, quartz, calcium carbonate, mica, kaolin, calcined kaolin, talc, diatomaceous earth and mixtures thereof . The emulsion paint has particularly good properties when the filler is a mixture of at least calcium carbonate and calcined kaolin.

Calcium carbonate can be used in various forms, for example in the form of chalk or calcite.

Practical tests have shown that the emulsion paint has particularly good abrasion resistance when the filler particles are small. The filler particles of the emulsion paint according to the invention advantageously have a size of less than 100 μm, in particular less than 80 μm, preferably from 0.1 to 50 μm, more preferably from 1 to 30 μm. Methods for determining the particle size are known to the person skilled in the art. For example, the particle size can be determined using a grindometer according to DIN EN ISO 1524, in particular according to DIN EN ISO 1524: 2013-06. The particle size of the fillers relates in particular to the maximum agglomerate size in the emulsion paint.

Furthermore, the particle size, in particular the particle size distribution, can also be determined by means of transmission electron microscopy. The particle size is preferably determined using a grindometer in accordance with DIN EN ISO 1524: 2013-06.

The pH of the emulsion paint according to the invention is from 10 to 13, preferably from 10 to 12, particularly preferably from 10.5 to 11.5. It has been found that emulsion paints with the specified pH values show no or only slight changes even after storage for several weeks, even if they were essentially free of preservatives. “Essentially free from preservatives” means that the emulsion paint contains no more than traces of preservatives, in particular in an amount of less than 2 ppm. Even more preferably, the pH of the emulsion paint is from 10.5 to 11.4. Emulsion paints according to the invention with such pH values have the additional advantage that they can also be used without special precautions with regard to occupational health and safety.

The emulsion paint according to the invention has a long shelf life and is well protected against microbial attack. According to a preferred embodiment of the invention, the pH value of the emulsion paint remains in the closed container at 22 ° C for a period of at least 4 weeks, preferably at least 8 weeks, preferably at least 12 weeks, more preferably at least 16 weeks or particularly preferably at least 20 weeks Essentially constant. “Essentially constant” here means that the pH value of the emulsion paint changes by less than 1, in particular by less than 0.8 or by less than 0.5. For example, if the pH on the day the emulsion paint was prepared is 11.9, the pH of the emulsion paint in a particularly preferred embodiment of the invention has not fallen below 11.5 after 20 weeks in a closed container at 22 ° C.

The emulsion paint according to the invention has excellent rheological properties and can be applied very easily with conventional painting utensils. According to a preferred embodiment of the invention, the emulsion paint has at a shear rate of 3.28 s ^-1, a viscosity of 10 to 20 Pa-s, preferably from 12 to 18 Pa-s, more preferably from 13 to 17 Pa-s or particularly preferably from 14 to 16.5 Pa-s , on. With such a viscosity, the emulsion paint is particularly suitable for common indoor and outdoor applications.

The emulsion paint according to the invention is also distinguished by the fact that the excellent flow properties remain stable even over prolonged storage times. According to a preferred embodiment, the viscosity of the emulsion paint in the closed container at 22 ° C. remains essentially constant over a period of at least 4 weeks, preferably at least 8 weeks, preferably at least 12 weeks, more preferably at least 16 weeks or particularly preferably at least 20 weeks. “Essentially constant” here means that the viscosity in the period described at a shear rate of 3.28 s ^-1 by less than 5 Pa-s, preferably less than 3 Pa-s, more preferably less than

2 Pa-s or more preferably less than 1 Pa-s changes.

Methods for determining the viscosity of coating compositions are known to the person skilled in the art. In particular, the viscosity can be determined with an MCR 92 rheometer at a temperature of 20 ° C. In particular, a plate geometry (diameter 50 mm) can be used for plate-on-plate measurement (distance 0.5 mm). 100 s ¹ or from 0.01 - - preferably a shear ramp of 0.01 s in this case is driven 1000 ^_1.

The emulsion paint according to the invention can furthermore contain additives in order to further optimize the properties of the emulsion paint. It is preferred here if the emulsion paint is from 0.01 to 10% by weight, preferably from 0.05 to 7% by weight, preferably from 0.1 to 5% by weight or particularly preferably from 0.5 to

3% by weight, based in each case on the total weight of the emulsion paint, contains additives. It is particularly advantageous here if the additives are dispersants, wetting agents, thickeners, defoamers and / or water repellants. With this Proportion of the additives mentioned, the properties of the emulsion paint according to the invention can be further improved.

Examples of rheology additives are methyl hydroxyethyl cellulose, layered silicate such as smectite and hectorite, xanthan gum, silicon dioxide, polyurethane resin, octan-1-ol (ethoxylated, 4-EO), alcohol alkoxylates, ethylene oxide-propylene oxide copolymers, maleic anhydride-diisobutylene copolymers and polyacrylic acid and polyacrylic acid, their salts, methyl celluloses, carboxymethyl celluloses, hydroxymethyl celluloses, polyurethanes, alkali metal phosphates, acrylates and salts of modified phosphoric acids, and mixtures thereof.

Examples of wetting agents and dispersants are diethyl maleate, tall oil, polyethylene polyamine, reaction products of tall oil and polyethylene polyamine, polyether, polyether phosphate, polyethylene glycol monomethyl ether, ortho-cresyl glycidyl ether, 2-ethylhexyl glycidyl ether, block copolymers, ammonium salts of acylate oxy-ethylene-alcohols (2), ammonium salts of poly (alcohol) oxyethylene copolymers, polyoxyethylene-polysiloxane, poly (alcohol) ethoxylated copolymers, polyoxyethylene (2) alkoxides of acylate oxy-polysiloxane, reaction products of tall oil and polyethylene polyamine, polyether, polyether phosphate , Polyesters, fatty acid modified polyesters, and mixtures thereof.

Examples of defoamers are polyurethane resins, polyglycols, triglycerides, polysiloxane-polyether copolymers and silicone oils.

Examples of water repellants are, in particular, oligomeric and polymeric siloxanes and silicone resins.

According to a preferred embodiment, the emulsion paint according to the invention is essentially free from preservatives, in particular from isothiazolines. “Essentially free from preservatives” means that the emulsion paint contains no more than traces of preservatives, in particular in an amount of less than 2 ppm. Examples of isothiazolines are methylisothiazolinone, chloromethylisothiazolinone, benzisothiazolinnone, octylisothiazolinone, dichloroctylisothiazolinone and butylbenzisothiazolinone. The emulsion paint is preferably free from ([([(2-dihydro-5-methyl-3 (2H) -oxazolyl) -l-methylethoxy] methoxy) methoxy] methanol.

According to a preferred embodiment of the invention, the emulsion paint according to the invention consists essentially of 5 to 75% by weight pigment and / or filler, 1 to 30% by weight binder, 0.05 to 10% by weight amino acid, 0.01 to 7% by weight. % Alkali plate and 20 to 60% by weight water. When it is said here that the emulsion paint consists essentially of the components mentioned, this means that the emulsion paint is at least 90% by weight, in particular at least 95% by weight, at least 97% by weight or at least 99% by weight % By weight, based on the total weight of the emulsion paint, consists of the components mentioned. According to this embodiment, up to 10% by weight (or up to 5% by weight, 3% by weight or 1% by weight) of the emulsion paint can consist of other components, in particular dispersants, wetting agents, thickeners, defoamers and / or water repellants are possible. Such emulsion paints are characterized by particularly good flow properties, a very long shelf life and excellent applicability.

According to a further embodiment, the emulsion paint consists of 5 to 75% by weight pigment and / or filler, 1 to 30% by weight binder, 0.05 to 10% by weight amino acid, 0.01 to 7% by weight alkali plate and 20 to 60% by weight water.

The invention also relates to a method for producing the emulsion paint according to the invention, comprising the steps a. Providing a composition containing, in each case based on the total weight of the composition, i. 5 to 75% by weight pigment and / or filler, ii. 1 to 30% by weight of binder, selected from the group consisting of poly (meth) acylate, poly (meth) acylate copolymer with a (meth) acylate content of at least 25% by weight, based on the total weight of the copolymer, poly (Meth) acrylate terpolymer with a (meth) acrylate component of at least 25% by weight, based on the total weight of the terpolymer, polystyrene, polystyrene copolymer with a styrene content of at least 25% by weight, based on the total weight of the copolymer and mixtures thereof, iii. 0.05 to 10% by weight amino acid, iv. 0.01 to 7 wt.% Alkali plate and v. 20 to 60% by weight of water, the amino acid comprising at least one amino group and each amino group of the amino acid having a pK a value of 9.0 to 10.0, b. Dispersing the in a. named components, c. Adjust the pH to a value from 10 to 13.

The steps listed can be carried out subject-specifically in any order. The pH adjustment can already be carried out in the step a. the composition presented. Alternatively, the final pH adjustment can also be carried out with a small amount of alkali metal, in particular sodium hydroxide and / or potassium hydroxide, after dispersing.

Dispersion methods for the production of emulsion paints are known to the person skilled in the art. The dispersing of the process step a. The composition provided can be done with very different dispersing devices.

For example, dispersion can be carried out using a dissolver, a three-roller, an agitator ball mill or a rotor-stator dispersing device.

What was said about the pigment in connection with the emulsion paint according to the invention also applies equally to the pigment of the process according to the invention.

What was said about the filler in connection with the emulsion paint according to the invention also applies equally to the filler of the method according to the invention. What was said about the binder in connection with the emulsion paint according to the invention also applies equally to the binder of the process according to the invention.

What was said about the amino acid in connection with the emulsion paint according to the invention also applies equally to the amino acid of the method according to the invention.

What was said about the alkali plate in connection with the emulsion paint according to the invention also applies equally to the alkali plate of the method according to the invention.

What has been said in connection with the emulsion paint according to the invention with regard to the pH value and viscosity also applies equally to the pH value and the viscosity of the process according to the invention.

The present invention also relates to the use of the emulsion paint according to the invention for indoor and / or outdoor use.

The invention is explained in more detail below by means of examples, which, however, only serve the purpose of illustration and are not limiting.

Examples

An emulsion paint with the following formulation shown in Table 1 was prepared by dispersing the constituents given in Table 1, the doses in each case in% by weight: Table 1

* Weight based on the aqueous solution; ie 0.4% by weight of solids content of KOH t weight information based on the aqueous solution; ie 7.5% by weight solids content of polyacrylate copolymer The emulsion paint obtained had a pH of 11.5. After 22 days at 50 ° C. in the closed container, this was 11.1 and thus remained essentially constant. The viscosity of the emulsion paint measured with an MCR92 rheometer from Anton Paar ^® at a temperature of 20 ° C with a PP50 measuring system (plate geometry; diameter 50 mm, distance 0.5 mm) at a shear rate of 3.28 s ¹ and at a The shear ramp from 0.01 to 100 s ^_1 was 16.3 Pa-s. The viscosity of the emulsion paint after 7 days in a closed container at 50 ° C. was 16.5 Pa-s, after 15 days in a closed container at 50 ° C. it was 16.6 Pa-s and after 22 days in a closed container at 50 ° C 18.3 Pa-s. As a result, the flow properties of the emulsion paint remained essentially constant.

The preservative-free emulsion paint produced was thus characterized by excellent storage stability and excellent flow properties.

Claims

P a t e n t a n s p r ü c h e

1 containing emulsion paint, each based on the total weight of the emulsion paint, a. 5 to 75% by weight pigment and / or filler,

5 b. 1 to 30% by weight of binder, selected from the group consisting of poly (meth) acrylate, poly (meth) acrylate copolymer with a (meth) acylate content of at least 25% by weight, based on the total weight of the copolymer, poly (Meth) acrylate terpolymer with a (meth) acrylate content of at least 25% by weight, based on

L0 is the total weight of the terpolymer, polystyrene, polystyrene copolymer with a styrene content of at least 25% by weight, based on the total weight of the copolymer and mixtures thereof, c. 0.05 to 10% by weight amino acid, i.e. 0.01 to 7 wt.% Alkali plate and

L5 e. 20 to 60% by weight of water, the amino acid comprising at least one amino group and each amino group of the amino acid having a pK a value of 9.0 to 10.0 and the pH value of the emulsion paint being from 10 to 13.

20 2 emulsion paint according to claim 1, characterized in that the amino acid is selected from the group consisting of alanine, glycine, leucine, isoleucine, valine, serine, threonine and mixtures thereof.

3. Emulsion paint according to one of claims 1 or 2, characterized in that the amino acid is alanine and / or glycine, in particular glycine.

4. Emulsion paint according to one of the preceding claims, characterized in that the emulsion paint is from 0.1 to 7% by weight, in particular from 0.2 to 5% by weight, from 0.3 to 2.5% by weight, from 0 , 4 to 2.0% by weight or from 0.5 to 1.5% by weight, based on the total weight of the emulsion paint,

Contains 5 amino acids.

5. Emulsion paint according to one of the preceding claims, characterized in that the emulsion paint is from 0.02 to 4% by weight, in particular from 0.05 to 3% by weight, from 0.2 to 2% by weight or from 0.4 up to 1.5% by weight, based on

L0 based on the total weight of the emulsion paint, containing alkali plates.

6. Emulsion paint according to one of the preceding claims, characterized in that the alkali plate is selected from the group consisting of alkali hydroxides such as potassium, sodium and / or lithium hydroxide,

L5 alkaline earth hydroxides such as magnesium, calcium and / or barium hydroxide,

Ammonium hydroxide, xonotlite and / or ettringite.

7. Emulsion paint according to one of the preceding claims, characterized in that the alkali plate is sodium hydroxide and / or

20 is potassium hydroxide.

8. Emulsion paint according to one of the preceding claims, characterized in that the binder is a poly (meth) acylate copolymer with a (meth) acylate content of at least 25% by weight, in particular at least

25 40% by weight or at least 50% by weight, based on the total weight of the

Copolymers.

9. emulsion paint according to any one of the preceding claims, characterized in that the emulsion paint from 2 to 25 wt.%, In particular

50 contains from 3 to 20% by weight or from 4 to 15% by weight, binder.

10. Emulsion paint according to one of the preceding claims, characterized in that the emulsion paint contains from 1 to 40% by weight, in particular from 5 to 30% by weight or from 10 to 25% by weight, based on the total weight of the emulsion paint, pigment, especially where the pigment

5 is selected from the group consisting of titanium dioxide, iron oxide yellow, allyide

(Monoazo), bismuth vanadate, perinones, rutile tin-zinc, quinacridones, diketopyrrolo-pyrrole, iron oxide red, phthalocyanine blue, dioxazine, cobalt blue, ultramarine blue, phthalocyanine green, chromium oxide green, cobalt green, carbon black, iron oxide black, pyrazolo-quinazolone Monoazo pigment and

L0 mixtures thereof, in particular where the pigment is titanium dioxide.

11. Emulsion paint according to one of the preceding claims, characterized in that the emulsion paint is from 5 to 65% by weight, in particular from 15 to 55% by weight or from 25 to 45% by weight, based on the total weight

L5 of the emulsion paint, contains filler, in particular where the filler is selected from the group consisting of dolomite, barium sulfate, feldspar, quartz, calcium carbonate, mica, kaolin, calcined kaolin, talc, diatomaceous earth and mixtures thereof, in particular where the filler is a mixture of at least Calcium carbonate and calcined kaolin is.

20th

12. Emulsion paint according to one of the preceding claims, characterized in that the pH value of the emulsion paint is from 10 to 12, in particular from 10.5 to 11.5 or from 10.5 to 11.4, and / or the pH value of the Emulsion paint in a closed container at 22 ° C over a

25 period of at least 4 weeks, in particular at least 8 weeks or at least 12 weeks or at least 16 weeks or at least 20 weeks, remains essentially constant.

13. Emulsion paint according to one of the preceding claims, characterized

20 indicated that the emulsion paint at a shear rate of 3.28 s ^-1

Viscosity from 10 to 20 Pa-s, in particular from 12 to 18 Pa-s or from 13 to 17 Pa-s or from 14 to 16.5 Pa-s, and / or the viscosity of the emulsion paint in a closed container at 22 ° C over a period of at least 4 weeks, in particular at least 8 weeks or at least 12 weeks or at least 16 weeks or at least 20 weeks, im

5 remains essentially constant.

14. Emulsion paint according to one of the preceding claims, characterized in that the emulsion paint from 0.01 to 10 wt .-%, in particular from 0.05 to 7 wt .-% or from 0.1 to 5 wt .-% or 0 , 5 to

L0 3% by weight, based in each case on the total weight of the emulsion paint, additives, in particular dispersants, wetting agents, thickeners, defoamers and / or water repellants.

15. Emulsion paint according to one of the preceding claims, characterized

L5 indicates that the emulsion paint is essentially free of preservatives.

16. A method for producing an emulsion paint according to any one of claims 1 to 15, comprising the steps:

20 a. Providing a composition containing, each based on the

Total weight of the composition, i. 5 to 75% by weight pigment and / or filler, ii. 1 to 30 wt.% Binder, selected from the group consisting of poly (meth) acrylate, poly (meth) acrylate copolymer with a

25 (meth) acylate content of at least 25% by weight, based on the

Total weight of the copolymer, poly (meth) acrylate terpolymer with a (meth) acrylate content of at least 25% by weight, based on the total weight of the terpolymer, polystyrene, polystyrene copolymer with a styrene content of at least 25% by weight, based on the total weight of the copolymer and mixtures thereof, iii. 0.05 to 10 wt.% Amino acid, iv. 0.01 to 7 wt.% Alkali plate and v. 20 to 60% by weight of water, the amino acid comprising at least one amino group and each amino group of the amino acid having a pK a value of 9.0 to 10.0 5 and, b. Dispersing the in a. named components, c. Adjust the pH to a value from 10 to 13.

17. The method according to claim 16, characterized in that the amino acid

LO is defined as in one of claims 2 to 4 and / or the alkali plate is defined as in one of claims 5 to 7 and / or the binder is defined as in one of claims 8 or 9 and / or the pigment is defined as in Claim 10 and / or the filler is defined as in claim 11 and / or the pH value is defined as in claim 12.

L5

18. Use of an emulsion paint according to one of claims 1 to 15 for indoor and / or outdoor use.

20th