DE202013012948U1 - Composition for coating - Google Patents

Abstract

Composition containing- a hydrophobic wax;- a silicone oil which mainly contains non-polar side chains; and - a hydrophilic binder - pigments and/or fillers, the composition having - a pigment volume concentration of 25 to 60%;

Description

The present invention relates to a composition for coatings, in particular for surfaces that are exposed to external weather, and a coating obtainable from this composition.

Surface coatings that are exposed to the elements are also exposed to microorganism growth, which is encouraged by moisture on or within the surface. Consequently, rapid drying of the surface is desirable, which can be achieved using appropriate coatings. The following principles exist for this purpose.

With so-called (highly) hydrophobic coatings, a high contact angle is formed, due to which water rolls off the surface - driven by gravity. Liquid water is drained away quickly. This will be in EP 1 144 332 described in detail.

With (super)-hydrophilic coatings, spherical water drops do not form on the surfaces, but rather the water drops spread and, in the best case, form a water film that can sometimes flow away. If the water film does not drain completely, the water film forms a large evaporation surface so that the surface can dry out more quickly through evaporation.

When it rains, the (highly) hydrophobic coatings usually dry quickly, whereas the (super) hydrophilic coatings absorb a very large amount of water and only slowly release it back into the environment after the rain has stopped. However, a damp coating has, among other things, a negative effect on thermal insulation.

However, with dew, the effectiveness of (highly) hydrophobic coatings is often limited because smaller drops form compared to rain and the total amount of water is lower than with rain, which is why drops of sufficient size may not form with (highly) hydrophobic coatings.

Consequently, the object of the present invention is to provide a coating composition which leads to improved re-drying of the surface even in the presence of dew.

• - ein hydrophobes Wachs;
• - ein Silikonöl welches hauptsächlich unpolare Seitenketten enthält; und
• - ein hydrophiles Bindemittel
• - Pigmente und/oder Füllstoffe

wobei
die Zusammensetzung

• - eine Pigment-Volumen-Konzentration von 25 bis 60 %; aufweist.

The problem according to the invention was solved by a composition containing

• - a hydrophobic wax;
• - a silicone oil which mainly contains non-polar side chains; and
• - a hydrophilic binder
• - Pigments and/or fillers

where
the composition

• - a pigment volume concentration of 25 to 60%; having.

The composition according to the invention and the resulting coating surprisingly have an increased re-drying and drainage rate. Regardless of theoretical considerations, it is assumed that the composition according to the invention and the resulting coating lead to an irregular distribution of the wax and the binder on the surface, which appears to be a consequence of the addition of the silicone oil. For this purpose, EXAFS measurements were carried out, which show areas of increased silicon concentration, which seems to support the theory. Water drops that reach the surface or form there, for example as a result of dew, are therefore simultaneously on areas of the surface that are covered by wax and which are covered by binder/silicone oil. These areas have different surface energies and consequently different wetting behavior. Due to the different wetting behavior of these areas, it is assumed that the water droplet tries to create different contact angles to the surface, which, especially in the transition from areas with different wetting behavior, leads to lower surface tensions and consequently to a faster union of the drops, which accelerates the drainage of the water.

As a result of the combination according to the invention, the surface that is coated with the composition has a significantly reduced hydrophobicity overall, in contrast to the above-mentioned (highly) hydrophobic surfaces. Lipophilic non-polar substances can no longer adhere as well due to the slightly increased polarity. Thus, the pollution resistance against lipophilic and non-polar substances was increased.

• - 0,1 bis 10 Gew.% des hydrophoben Wachses;
• - 0,01 bis 2 Gew.% des Silikonöls;
• - 10 bis 60 Gew.% des hydrophilen Bindemittels; und
• - 30 bis 80 Gew. % der Pigmente und/oder Füllstoffe, wobei sich die Menge auf die Gesamtheit der Pigmente und Füllstoffe bezieht;

jeweils bezogen auf den Feststoffanteil der Zusammensetzung.Preferably the composition contains:

• - 0.1 to 10% by weight of the hydrophobic wax;
• - 0.01 to 2% by weight of the silicone oil;
• - 10 to 60% by weight of the hydrophilic binder; and
• - 30 to 80% by weight of the pigments and/or fillers, the amount referring to the total of the pigments and fillers;

each based on the solids content of the composition.

To measure the contact angle of the wax and silicone oil and determine the surface energy (OFE) and its polar and dispersive proportion, a mixture of 3.8% by weight (wax) or 1.1% by weight of silicone oil, based on the solids content, was used in a The polyacrylate binder specified in the experimental part was used because direct measurement on pure wax and pure silicone oil is not possible. For detailed determination of the contact angle, please refer to the experimental part. Unless otherwise noted, reference will be made to this contact angle in the following regarding the contact angle of wax and silicone oil. In addition, unless otherwise noted, an equilibration time of 3 min was allowed for all contact angle measurements.

In the present application, “hydrophobic” means that the static initial contact angle of water is > 90° after 3 min of equilibration.

In the present application, “hydrophilic” means that the static initial contact angle of water after 3 min of equilibration is ≤ 90°.

Preferably, the binder has a static initial contact angle of water after 3 minutes of equilibration of ≤ 90°, more preferably ≤ 80°, more preferably ≤ 75°.

Preferably, the wax has a static initial contact angle of water after 3 minutes of equilibration which is at least 5°, preferably at least 10° higher than the static initial contact angle of water of the binder after 3 minutes of equilibration.

The static initial contact angle of water after 3 minutes of equilibration of the silicone oil is preferably at least 5°, preferably at least 10° higher than the static initial contact angle of water of the binder after 3 minutes of equilibration.

The binder normally has a polar surface energy content of 10% or more, preferably 15% or more. Normally the polar proportion is not higher than 50%.

The binder normally has a dispersive surface energy content of less than 90%, preferably less than 85%.

Preferably, the polar portion of the average OFE of the binder is 2 to 20 mN/m, more preferably 4 to 15 mN/m.

The dispersive proportion of the average OFE of the binder is preferably 20 to 50 mN/m, more preferably 28 to 40 mN/m.

The average OFE of the binder is preferably 22 to 70 mN/m, more preferably 25 to 50 mN/m, even more preferred 30 to 45 mN/m.

By adding wax and/or silicone oil, the polar portion of the OFE is reduced. The wax preferably reduces the polar proportion of the OFE by at least 8 percentage points, preferably by at least 12 percentage points, compared to the pure binder.

The reduction in the polar portion of the OFE of the binder due to the addition of the wax and/or silicone oil is preferably at least 2 mN/m, more preferably at least 4 mN/m, even more preferably 6 mN/m.

Preferably the wax has a polar content of OFE of 10% or less, more preferred is 8% or less.

The wax normally has a dispersive content of OFE of more than 90%, preferably more than 92%.

Preferably, the polar proportion of the average OFE of the wax is 0.1 to 6 mN/m, more preferably 0.5 to 4 mN/m.

The dispersive proportion of the average OFE of the wax is preferably 22 to 52 mN/m, more preferably 28 to 48 mN/m.

The average OFE of the wax is preferably 23 to 58 mN/m, more preferably 25 to 50 mN/m, even more preferred 29 to 38 mN/m.

Preferably the silicone oil has a polar content of OFE of 8% or less, preferably 6% or less.

The silicone oil normally has a dispersive content of OFE of more than 90%, preferably more than 92%.

Preferably, the polar proportion of the average OFE of the silicone oil is 0.1 to 5 mN/m, more preferred is 0.5 to 3 mN/m.

The dispersive proportion of the average OFE of the silicone oil is preferably 25 to 50 mN/m, more preferably 30 to 45 mN/m.

The average OFE of the silicone oil is preferably 20 to 70 mN/m, more preferably 26 to 50 mN/m, even more preferred 30 to 46 mN/m.

The composition according to the invention results in areas with high and low OFE on the surface, expressed by different high or low polar and/or dispersive portions of the OFE. In particular, the polar component varies greatly, as shown in the experimental part.

The areas of high OFE usually correspond to the OFE of the binder and the areas of low OFE usually correspond to the OFE of the wax.

The OFE of the composition is averaged from at least 5 pairs of measured values (water/diiodomethane) and thus represents an average value of the OFE (“average OFE”) of the areas with high OFE and the areas with low OFE.

The OFE of the composition is therefore preferably at least 1.5 mN/m lower than that of the binder, preferably at least 2 mN/m lower than that of the binder, more preferably at least 3 mN/m lower than that of the binder.

Preferably, the polar proportion of the average OFE of the composition is 1 to 10 mN/m, more preferably 1 to 6 mN/m, even more preferably 1 to 4 mN/m.

The polar fraction of the average OFE of the composition is preferably at least 2 mN/m lower than the polar fraction of the average OFE of the binder, more preferably at least 4 mN/m lower than the polar fraction of the average OFE of the binder, even more preferably at least 6 mN /m lower than the polar portion of the average OFE of the binder.

The dispersive proportion of the average OFE of the composition is preferably 14 to 59 mN/m, more preferred is 20 to 50 mN/m, even more preferred is 25 to 40 mN/m.

The average OFE of the composition is preferably 15 to 60 mN/m, more preferred is 22 to 52 mN/m, even more preferred is 27 to 42 mN/m.

The ratio of the dispersive to the polar portion of the average OFE of the composition is preferably 50:1 to 1:1, more preferably 40:1 to 2:1.

The average static initial contact angle of water after 3 minutes of equilibration of the composition is preferably 50° to 130°, more preferred is 60 to 125°, even more preferred is 70° to 120°.

The static initial contact angle of water after 3 minutes of equilibration of the composition is preferably 2° to 20° higher than that of the binder, preferably 5 to 15° higher.

The average static initial contact angle of diiodomethane after 3 minutes of equilibration of the composition is preferably 40° to 60°, more preferably 45° to 55°.

Preferably, the composition has an initial contact angle of water after 0 seconds of more than 100°. The contact angle of water decreases more quickly compared to prior art compositions. Typically, the contact angle of water to the composition after 0 sec is 130° or smaller.

The initial contact angle of water after 30 seconds of equilibration is preferably at least 4° lower, more preferably at least 6° lower than the static initial contact angle of water after 0 seconds.

The initial contact angle of water after 3 minutes of equilibration is preferably at least 8° lower, more preferably at least 10° lower than the static initial contact angle of water after 0 seconds.

Preferably, the water content on a vertically arranged surface coated with the composition according to the invention after spraying water in an amount of 85 g/m ² after 30 minutes at 23 ° C and 50% relative humidity is less than 10% by weight of the water originally applied , preferably less than 6.0% by weight.

The coating was usually applied with a wet layer thickness of 200 µm, dried for 2 days at room temperature and the sprayed area is usually 414 cm ² .

Preferably, the water content on a vertically arranged surface coated with the composition according to the invention after immersion in water for 1 second after 30 minutes at 23 ° C and 50% relative humidity is less than 3.0% by weight of the water originally applied, preferably less than 2.5% by weight. The coating was usually applied with a wet layer thickness of 200 µm, dried for 2 days at room temperature and the sprayed area is usually 414 cm ² .

Conventional binders such as those known in the field of coatings and paints can be used as binders. Preference is given to homopolymers, copolymers or terpolymers of acrylic acid and/or methacrylic acid, itaconic acid and acid esters such as ethyl acrylate, butyl acrylate; styrene, substituted or unsubstituted vinyl chloride, vinyl acetate, acrylamides and acrylonitrile; water-thinnable alkyd polymers, combinations of (meth)acrylic/alkyd polymers, polyvinyl alcohol and mixtures thereof are used.

Homopolymers or copolymers of acrylic acid and/or methacrylic acid are particularly preferred.

Preferably, the silicone oil contains mainly hydrocarbyl side chains, for example C ₁ to C ₂₀ hydrocarbyl side chains, more preferably mainly alkyl side chains, for example C ₁ to C ₂₀ alkyl side chains. Due to the absence of polar side chains, the silicone oil has a strongly non-polar character. Normally the alkyl chains contain no more than 5 carbon atoms. Branched and linear polysiloxanes with methyl, ethyl or propyl side chains are particularly preferred.

“Mainly non-polar side chains” in the present application means that no polar side chains are intentionally introduced during the synthesis of the silicone oils.

“Mainly hydrocarbyl side chains” in the present application means that no side chains other than hydrocarbyl side chains are intentionally introduced in the synthesis of the silicone oils.

“Mainly alkyl side chains” in the present application means that no side chains other than alkyl side chains are intentionally introduced during the synthesis of the silicone oils.

The same applies to C ₁ to C ₂₀ hydrocarbyl side chains and C ₁ to C ₂₀ alkyl side chains.

In a preferred embodiment, the silicone oil contains exclusively hydrocarbyl side chains, more preferably exclusively alkyl side chains according to one of the above-mentioned embodiments.

The silicone oil preferably has no alkoxy side chains. The absence of alkoxy side chains can be detected by the absence of the symmetrical Si-OC stretching vibration in the FTIR spectrum (940 to 970 cm ^-1 ).

Preferably, the silicone oil has a molecular weight of 1000 to 20,000 g/mol, more preferably 4000 to 10,000 g/mol.

The silicone oil preferably has a viscosity of 75 to 135 mm ² /s, more preferably 85 to 125 mm ² /s.

The composition preferably contains only silicone oils that have the above-mentioned properties or their preferred embodiments.

As mentioned above, it is assumed that the silicone oil leads to an irregular distribution of the wax and the binder on the surface, i.e. has a flow-disturbing effect, which in turn is assumed to be one of the causes of the effect of the invention. In contrast, many silicone compounds, e.g. wetting agents that can also be silicon-based, have a flow-promoting effect, which is usually achieved through surfactant-like structures.

Preferably the pigment volume concentration of the composition is 30 to 55%, even more preferred is 35 to 50%. The wax preferably has a melting range within the range of 80 and 160 ° C. The wax is usually silicon-free.

Examples are natural waxes, e.g. B. beeswax, carnauba wax and paraffin waxes, and synthetic waxes such as polyalkylene waxes, polyamides, oxidized polyalkylene waxes, waxes made from low molecular weight copolymers of ethylene and acrylic acid or acrylates. Particularly preferred are polyethylene or polyamide waxes and most preferred are polyethylene waxes. In the case of more than one wax, the quantities and temperature information refer to the entirety of the waxes, but preferably only one wax is used.

The amount of wax is preferably 0.2 to 5% by weight based on the solids content of the composition.

The amount of silicone oil is preferably 0.1 to 1.5% by weight based on the solids content of the composition, more preferably 0.2 to 1.0% by weight based on the solids content of the composition.

The pigments and/or fillers are preferably made from pyrogenically precipitated silica, precipitated silica, silicon-aluminum mixed oxides, carbonates, for example alkaline earth metal carbonates such as calcium carbonate, silicon dioxide, silicates, for example aluminosilicates, sulfates, for example barium sulfates, titanium dioxide, colored pigments, for example iron oxides, bismuth vanadates or Mixtures of these selected. More preferred are titanium dioxide, silicates and carbonates.

In one embodiment, the pigments and/or fillers consist of inorganic pigments and/or inorganic fillers.

The amount of pigments and fillers is preferably 35 to 50% by weight, based on the solids content of the composition, based on the total of the pigments and fillers.

The particle size of the pigments and fillers is normally in the range from 0.1 to 100 µm, preferably 0.2 to 50 µm.

The composition can further contain up to 8.0% by weight, preferably up to 5.0% by weight, based on the solids content of the composition, of conventional additives, for example dispersants, thickeners, wetting agents, biocides, defoamers, etc.

The composition is preferably a molding or coating composition, more preferably a paint or plaster.

The composition can be in the form of an aqueous dispersion. If an aqueous dispersion is present, the water content is preferably 20 to 60% by weight. However, the composition according to the invention can also be a dispersion of one or more organic solvents. Such organic solvents can be aliphatic or aromatic hydrocarbons, for example toluene, alcohols esters or ketones, which are known as solvents for binders and varnishes. If a dispersion of organic solvents is present, the solvent content is preferably 20 to 50% by weight.

The composition according to the invention can alternatively be a dispersion of a mixture of water and the aforementioned organic solvents.

The amount of water or organic solvent added is selected by the expert depending on the intended application. In the case of dispersions of a mixture of water and the aforementioned organic solvents, the water content is preferably more than 50% by weight based on the total mass of water and organic solvent.

• - ein hydrophobes Wachs;
• - ein Silikonöl welches hauptsächlich unpolare Seitenketten enthält; und
• - ein hydrophiles Bindemittel
• - Pigmente und/oder Füllstoffe wobei die Zusammensetzung
• - eine Pigment-Volumen-Konzentration von 35 bis 55 %; aufweist.

The invention further provides a coating on a substrate surface containing the coating

• - a hydrophobic wax;
• - a silicone oil which mainly contains non-polar side chains; and
• - a hydrophilic binder
• - Pigments and/or fillers, the composition
• - a pigment volume concentration of 35 to 55%; having.

• - 0,1 bis 10 Gew.% des hydrophoben Wachses;
• - 0,01 bis 2 Gew.% des Silikonöls;
• - 10 bis 60 Gew.% des hydrophilen Bindemittels; und
• - 30 bis 80 Gew. % der Pigmente und/oder Füllstoffe, wobei sich die Menge auf die Gesamtheit der Pigmente und Füllstoffe bezieht;

Preferably the coating contains

• - 0.1 to 10% by weight of the hydrophobic wax;
• - 0.01 to 2% by weight of the silicone oil;
• - 10 to 60% by weight of the hydrophilic binder; and
• - 30 to 80% by weight of the pigments and/or fillers, the amount referring to the total of the pigments and fillers;

The coating is preferably in the cured form.

The preferred embodiments of the composition according to the invention are also preferred embodiments of the coating according to the present invention.

The substrate is preferably a wall, more preferred are external surfaces that are exposed to weather, for example external facades of buildings.

MEASUREMENT METHODS

Melting point wax:

ISO EN 11357-3

Contact angle and surface energy as well as their polar and dispersive components

Water and diiodomethane were used as test substances for the contact angle. The drop size was 2µl to 4µl.

Since a direct measurement of a wax surface may not be possible because the wax can crystallize when it hardens and therefore a measurement is not possible or is too soft, a mixture of 3.85% by weight of wax and 96.15% by weight of the binder mentioned below was obtained to the solids content and an appropriate coating is created. The contact angle measurements were carried out on this surface.

Silicone oils are normally viscous liquids and therefore direct measurement on their surface is usually not possible. Therefore, a mixture of 1.13% by weight of silicone oil was obtained and 98.87% by weight of the binder mentioned below based on the solids content was prepared and a corresponding coating was created. The contact angle measurements were carried out on this surface.

The binder used was an aqueous dispersion based on a copolymer of acrylic and methacrylic acid esters with a solids content of 46% by weight and a Brookfield viscosity of approximately 7000 mPa s DIN EN ISO 2555 (Spindle 4; 20 rpm; 23°C), available as Mowilith LDM 7724 from Celanese.

The static contact angle was determined after 2 days of drying at 23 °C and 50% relative humidity. After applying the water drop or diiodomethane drop, wait 180 seconds before the measurement is carried out.

The contact angle at the three-phase contact line between solid, liquid and gas is determined using the G1 contact angle measuring device from Krüss. At least five drops are measured at different points on each test specimen.

The surface energy is determined using the Owens-Wendt-Rabel-Kaeble method as follows (source Krüss AG).

OWENS und WENDT legten ihre Gleichung der Grenzflächenspannung

zugrunde und kombinierten sie mit der YOUNG-Gleichung

According to OWENS, WENDT, RABEL and KAELBLE, the surface tension of each phase can be split into a polar and a dispersive part:

OWENS and WENDT presented their equation of interfacial tension

and combined them with the YOUNG equation

an. Die angepasste Gleichung sieht folgendermaßen aus:

The two authors solved the system of equations using contact angles of two liquids with known dispersive and polar components of the surface tension. Equations 3 and 4 become combined and the resulting equation is adapted to the general straight line equation by converting. $$y=mx+b$$

at. The fitted equation looks like this:

In a linear regression of the plot of y against x, σ _s P results from the square of the slope of the line m and σ _s D from the square of the ordinate intercept b.

The surface energies are given in mN/m.

Pigment volume concentration

The pigment volume concentration (EN ISO 4618-1) reflects the volume ratio between pigments/fillers and the binder in the coating film.

The additives also included in the recipe were not taken into account in the calculation. Solvents and water are no longer contained in the hardened film and are therefore also eliminated. The wax and silicone oil, if present, were not taken into account in the calculation.

Viscosity silicone oil

DIN 53015

FTIR (absence of symmetrical Si-O-C stretching vibration)

The measurement was carried out using a Perkin-Elmer Spectrum 100 FTIR spectrometer with Universal ATR Accessory. The absence of the symmetrical Si-OC stretching vibration at 940 - 970 cm ^-1 indicates the absence of alkoxy side chains.

EXAMPLES:

Materials used:

Binder:

• Titandioxid, mittlere Partikelgröße < 1 µm
• anorganische Füllstoffe:
• Calziumcarbonat, mittlerer Teilchendurchmesser D₅₀ 2,5 µm
• Magnesiumsilikat
• Aluminiumsilikat, mittlerer Teilchendurchmesser D₅₀ 25 µm

Aqueous dispersion based on a copolymer of acrylic and methacrylic acid esters having a solids content of 46% by weight and a Brookfield viscosity of approx. 7000 mPa s DIN EN ISO 2555 (Spindle 4; 20 rpm; 23°C), available as Mowilith LDM 7724 from Celanese.
inorganic pigment:

• Titanium dioxide, average particle size < 1 µm
• inorganic fillers:
• Calcium carbonate, average particle diameter D ₅₀ 2.5 µm
• Magnesium silicate
• Aluminum silicate, average particle diameter D ₅₀ 25 µm

Wax:

Polyethylene wax with a melting range of 100 to 110 °C, a density of 0.98 g/cm ³ and a viscosity of 40 mPa s (DIN 53019 1.921s-1). Dispersion with a solids content of 35% by weight

silicone oil

Alkoxy group-free dimethylpolysiloxane having a viscosity of 90 mm ² /s and a molecular weight of. 6100 g/mol

First, mixtures of the pure binder and wax and/or silicone oil were examined. For this purpose, the compositions from Table 1 were applied with a wet layer thickness of 200 µm and dried as described above and the contact angles were determined after 3 minutes of equilibration of the drop on the surface with water and diiodomethane, the OFE, as well as the dispersive (DA) and polar portion (PA). OFE determined.

The quantities in Table 1 of the PE wax refer to an aqueous dispersion with a solids content of 35% by weight and that of the binder to an aqueous dispersion with a solids content of 46% by weight. The silicone oil is present as a pure compound. Table 1 Contact angle [°] OFE* THERE* PA* THERE[%] PA[%] DA/PA Water Diiodomethane binder 73.4 53.3 40.4 32.4 8.0 80.2 19.8 4.0 Binder + 5 wt.% wax 91.7 54.2 33.5 31.9 1.6 95.3 4.7 20.2 Binder + 0.5% by weight silicone oil 88.4 44.4 38.9 37.3 1.6 96.0 4.0 23.9 Binder + 4.5 wt.% wax +0.5 wt. silicone oil 89.3 47.4 37.3 35.7 1.6 95.8 4.2 22.8 Binder + 5 wt.% wax +0.5 wt. silicone oil 89.9 47.8 37.0 35.5 1.5 96.0 4.0 24.0
* Unit [mN/m]

The clear increase in the contact angle of water when wax and/or silicone oil is added can be seen.

Furthermore, the following composition was prepared and the contact angle, the OFE and their polar and dispersive proportion of the resulting coating were determined (data in wt.%). Water: 10.0 Acrylate binder dispersion Solids content 46% by weight 43.0 Titanium dioxide 14.0 Fillers (silicates/carbonates) 24.0 Additives (dispersants, thickeners, defoamers, biocides, etc. 3.5 PE wax dispersion solids content 35% by weight 5.0 Dimethylpolysiloxane 0.5

The resulting coating had a PVC of 40%

In addition, the pigment and filler content was varied to obtain compositions with PVC 30, 50 and 60. The results are shown in the following table. Table 2 Contact angle [°] OFE* THERE* PA* THERE[%] PA[%] DA/PA # Water Diiodomethane PVC 30 86.6 49.3 37.1 34.7 2.4 93.5 6.5 14.4 5.6 PVC 40 87.0 53.2 35.1 32.8 2.2 93.7 6.3 14.8 5.8 PVC 50 83.0 49.8 37.9 34.4 3.6 90.6 9.4 9.6 4.4 PVC 60 94.5 50.5 34.8 34.0 0.8 97.7 2.3 43.0 7.2
* Unit [mN/m]
# PA [mN/m] (binder) - PA [mN/m] (composition)

The polar proportion of the binder was 8.0 mN/m or 19.8%.

Between a PVK of 40% and 50% there is a visible, sudden improvement in the wetting behavior; at PVK = 60% it deteriorates again. It is assumed here that the high proportion of pigments and fillers is noticeable.

Dynamics of the contact angle (water)

It can be seen below that the change in the contact angle over time occurs significantly faster in the color formulation according to the invention than in the reference examples.

In addition, the difference between the contact angle at 180 seconds is larger compared to the contact angle at 0 seconds.

For this purpose, the color formulation with PVK = 40% from the previous example was used, with the wax and silicone oil content being varied as in the following tables 3a to 3d. For the wax, the information as above refers to a dispersion with a solids content of 35% by weight. Table 3a No. Reference 1 Description 0% wax 0% silicone oil Time in seconds Measurement 1 Measurement 2 Measurement 3 Measurement 4 Measurement 5 0 93.2 90.3 96.6 94.4 90.7 30 91.5 89.1 94.2 92.2 89.1 60 88.0 88.5 93.6 91.8 88.2 90 88.4 87.9 92.0 91.4 87.6 120 87.8 87.4 90.1 90.2 86.9 150 87.0 86.9 88.5 89.5 86.0 180 86.3 86.4 87.9 89.3 86.7
ng not measured Table 3b No. Reference 2 Description 4.5% wax 0% silicone oil Time in seconds Measurement 1 Measurement 2 Measurement 3 Measurement 4 Measurement 5 0 95.9 94.6 94.4 108.5 110.3 30 95.0 93.6 94.2 107.6 106.7 60 93.8 93.1 93.8 106.8 103.7 90 91.8 92.6 93.4 105.8 103.1 120 86.2 92.0 92.7 105.1 102.5 150 85.2 91.5 92.1 104.7 102.3 180 84.5 90.9 91.4 103.9 101.4 Table 3c No. Reference 3 Description 0% wax 0.5% silicone oil Time in seconds Measurement 1 Measurement 2 Measurement 3 Measurement 4 Measurement 5 0 94.9 93.5 94.6 95.3 95.5 30 92.0 93.2 93.8 94.0 95.4 60 91.7 92.5 92.8 93.1 94.1 90 90.8 91.9 92.1 92.4 94.1 120 90.0 91.3 91.4 91.5 93.1 150 89.3 90.6 90.8 90.8 92.7 180 88.6 90.0 90.1 90.2 91.0 Table 3d No. According to the invention Description 4.5% wax; 0.5% silicone oil Time in seconds Measurement 1 Measurement 2 Measurement 3 Measurement 4 Measurement 5 0 103.4 110.0 103.0 102.7 107.6 30 95.8 97.8 96.0 94.3 96.8 60 95.0 95.1 94.6 93.3 95.9 90 93.0 93.9 93.7 92.7 95.3 120 92.3 92.0 92.9 91.5 94.6 150 91.4 92.3 92.5 90.7 94.0 180 91.0 92.0 92.0 90.2 93.5
ng not measured

• : Referenz 1 Zusammensetzung + 0% Wachs + 0% Silikonöl
• : Referenz 2 Zusammensetzung + 4,5% Wachs + 0% Silikonöl
• : Referenz 3 Zusammensetzung + 0% Wachs + 0,5% Silikonöl
• : Referenz 4 Zusammensetzung + 4,5% Wachs + 0,5% Silicon

The time course of the decrease in the contact angle is in until shown.

• : Reference 1 composition + 0% wax + 0% silicone oil
• : Reference 2 composition + 4.5% wax + 0% silicone oil
• : Reference 3 composition + 0% wax + 0.5% silicone oil
• : Reference 4 composition + 4.5% wax + 0.5% silicone

As can be seen from the measurements above, the formulation according to the invention not only has a higher contact angle at 0 seconds, the drop in the contact angle after 180 seconds is 12° or more and is therefore also higher than in the reference examples. In addition, there is a significant drop in the contact angle within the first 30 seconds.

The compositions according to the invention also have faster drying of the surface.

This was proven using the following experiments.

For this purpose, lifts with a wet layer thickness of 200 µm were created on PVC film and dried for 2 days at room temperature. The surface area was 414 cm ² .

The coated PVC film was suspended and tared. Then spray approx. 3.5 g of distilled water from a distance of approx. 35 cm. The re-drying was observed for 30 min and the weight was recorded every 5 min. The test was carried out in a standard climate of 23°C/50% rel. Humidity carried out.

For this purpose, the composition according to the invention PVK 40 listed above was used with the difference that 4.5% by weight of wax dispersion was used instead of 5.0% by weight of wax dispersion, hereinafter referred to as IE3.

IE3 was compared with a highly hydrophobic coating (Refl) having a contact angle with water of 125° after 3 minutes of equilibration time and a hydrophilic surface made of conventional dispersion silicate facade paint without hydrophobing agents (Ref2). Ref2 visually looks dry after approx. 15 minutes; as can be seen from the measurement, the coating contains a significant amount of moisture. Table 4 Ref1 IE3 Ref2 4.5% wax 0.5% silicone oil [G] [%] [G] [%] [G] [%] begin 3.71 100.0 3.52 100.0 3.51 100.0 5' 3.29 88.7 2.17 61.6 2.20 62.7 10' 2.82 76.0 1.50 42.6 1.74 49.6 15' 2.34 63.1 1.00 28.4 1.25 35.6 20' 1.91 51.5 0.62 17.6 0.91 25.9 25' 1.45 39.1 0.35 9.9 0.57 16.2 30' 1.05 28.3 0.16 4.5 0.30 8.5

The time course of the amount of water remaining on or in the surface is in (weight/time) and 6 (wt.%/time).

In addition, the above-mentioned coatings were completely immersed in water for 1 second and then hung on the scales within 5 seconds.

The re-drying was observed for 30 min and the weight was recorded every 5 min. The test was carried out in a standard climate of 23°C/50% rel. Humidity carried out Table 5 Ref1 IE3 Ref2 4.5% wax 0.5% silicone oil [G] [%] [G] [%] [G] [%] begin 1.53 100 1.05 100 2.60 100.00 5' 0.52 34.0 0.26 24.8 1.69 65.0 10' 0.26 17.0 0.19 18.1 1.21 46.5 15' 0.12 7.8 0.13 12.4 0.79 30.4 20' 0.08 5.2 0.10 9.5 0.45 17.3 25' 0.06 3.9 0.06 5.7 0.21 8.1 30' 0.03 1.0 0.02 1.9 0.10 3.9

The time course of the amount of water remaining on or in the surface is in (weight/time) and 8 (wt.%/time).

Water absorption according to EN1062-1 and -3: W value permeability to water. This property allows the resistance of the coating to the penetration and absorption of water to be assessed. Ref IE3 Ref2 0.05 kg/(m ^{2 h0} _' ⁵ ) 0.02 kg/(m ² h ^0.5 ) 1.17 kg/(m ² h ^0.5 ) Class W3 Class W3 Class W1

QUOTES INCLUDED IN THE DESCRIPTION

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Cited patent literature

• EP 1144332 [0003]

Non-patent literature cited

• DIN EN ISO 2555 [0087, 0098]

Claims (14)

Composition containing - a hydrophobic wax; - a silicone oil which mainly contains non-polar side chains; and - a hydrophilic binder - Pigments and/or fillers where the composition - a pigment volume concentration of 25 to 60%; having. The composition according to Claim 1 , wherein the wax has a static initial contact angle of water after 3 min of equilibration that is at least 5° higher than the static initial contact angle of water of the binder after 3 min of equilibration. The composition according to Claim 1 or 2 , where the wax has a polar portion of the surface energy of 10% or less. The composition according to any one of the preceding claims, the wax lowers the polar fraction of the surface energy by at least 8 percentage points. The composition according to any preceding claim, wherein the silicone oil contains predominantly hydrocarbyl side chains. The composition according to any one of the preceding claims, wherein the silicone oil has an average molecular weight of 1000 to 20,000 g/mol. The composition according to any preceding claim, wherein the silicone oil has a viscosity of 75 to 135 mm ² /s. The composition according to any one of the preceding claims, wherein the pigment volume concentration is 30 to 55% by volume. The composition according to any preceding claim, wherein the wax is a polyethylene or a polyamide wax. The composition according to any one of the preceding claims, wherein the composition is a molding or coating composition. The composition according to Claim 10 wherein the composition is a paint or plaster. Containing coating on a substrate surface - a hydrophobic wax; - a silicone oil which mainly contains non-polar side chains; and - a hydrophilic binder - Pigments and/or fillers where the composition - a pigment volume concentration of 25 to 60%; having. Use of a composition according to one of the Claims 1 until 9 as a molding or coating compound. Use after Claim 13 wherein the molding or coating material is a paint or plaster.

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