JP2017507195A - Coating composition - Google Patents

Abstract

Disclosed is a composition for forming a coating film, which can improve the re-drying property of a substrate surface on which condensation has occurred. A composition comprising a hydrophobic wax, a silicone oil mainly containing non-polar side chains, a hydrophilic binder, a pigment and / or filler, and containing the pigment at a concentration of 25% to 60% by volume, and hydrophobic Composition comprising a water-soluble wax, a silicone oil mainly containing non-polar side chains, a hydrophilic binder, a pigment and / or a filler, the pigment surface containing a pigment at a concentration of 25% to 60% by volume Also related to things. [Selection figure] None

Description

  The present invention relates to a coating composition, in particular a coating composition for surfaces exposed to outdoor exposure, as well as a coating obtained from this composition.

Surface coatings that are exposed to the outside air are also exposed to microorganisms that grow due to moisture on or within the surface. Therefore, rapid drying of the surface is desirable and rapid drying can be achieved by the use of a suitable coating. In this case, the following principles apply:
When a so-called (highly) hydrophobic coating (coating film) is formed, a high contact angle is realized, and water forms water droplets on the surface due to the influence of gravity. Liquid water disappears quickly. The details of this are described in Patent Document 1.

In the case of a (super) hydrophilic coating, spherical water droplets are not formed on the surface. Instead, water droplets spread, and in the worst case, a water film is formed. If the water film forms a wide evaporation surface without completely flowing out the water film, the surface is dried more rapidly by evaporation.
In the rain, (highly) hydrophobic coatings generally achieve rapid drying. On the other hand, the (super) hydrophilic coating absorbs a large amount of water and, after the rain has stopped, again releases water to the surroundings over time. However, the wet application has an adverse effect on the heat insulation performance.

  It should be noted that the effect of the (highly) hydrophobic coating is limited to condensation. Compared to rain, the water droplets produced are smaller and the total amount of water is less than rain, ie in the case of (highly) hydrophobic coatings, water droplets of the right size are produced. It is because it does not.

European Patent Application Publication No. 1143332

  Accordingly, an object of the present invention is to provide a coating composition in which the re-drying property of a surface on which condensation has occurred is improved.

The above objective is in accordance with the present invention,
Hydrophobic wax,
Silicone oils containing mainly non-polar side chains, and hydrophilic binders,
A composition comprising a pigment and / or a filler,
Solved by compositions containing pigments at a concentration of 25% to 60% by volume.

The compositions according to the invention and the resulting coatings surprisingly increase the rate of re-drying and disappearance. Apart from theoretical considerations, it is assumed that the composition according to the invention and the resulting coatings have a non-uniform distribution of wax and binder on the surface. This appears to be the result of the addition of silicone oil. For this reason, when EXAFS measurement was performed, a region of high silicone concentration was shown, and the result seems to support the above theory. The arrival of water droplets on the surface or the in situ generation of water droplets, for example the formation of water droplets as a result of condensation, can therefore occur between the surface area covered with wax and the surface area covered with binder / silicone oil. It happens simultaneously in both. These regions have different surface energies resulting in different wettability. As a result of the difference in wettability in these regions, it is likely that the water droplets will attempt to establish different contact angles with the surface, leading to a decrease in surface tension, especially at the boundary from regions with different wettability. As a result, water droplets aggregate more quickly, thereby accelerating the disappearance of water.
With the composition according to the invention, the surface to which the composition is applied is reliably reduced overall in hydrophobicity, in contrast to the (highly) hydrophobic surfaces mentioned above. For lipophilic non-polar substances, this does not show high adhesion, since the polarity hardly increases. In this way, the contamination resistance against lipophilic and non-polar substances is also increased.

It is a measurement result in the case of the composition of Reference Example 1 + 0% wax + 0% silicone oil. It is a measurement result in the case of the composition of Reference Example 2 + 4.5% wax + 0% silicone oil. It is a measurement result in the case of the composition of Reference Example 3 + 0% wax + 0.5% silicone oil. It is a measurement result in the case of the composition of Reference Example 4 + 4.5% wax + 0.5% silicone oil. The amount of water remaining in the surface layer is plotted per unit time (mass / hour). The amount of water remaining in the surface layer plotted per hour (% by mass) is shown. The amount of water remaining in or on the surface layer plotted per hour (mass / hour) is shown. The amount of water remaining in or on the surface layer plotted per hour (% by mass) is shown.

The composition of the present invention preferably comprises:
0.1 to 10% by weight of a hydrophobic wax;
0.01 to 2% by weight of silicone oil;
10 to 60% by weight of hydrophilic binder; and 30 to 80% by weight of pigments and / or fillers (the amounts on the left relate to the total amount of pigment and filler).
The above is a value based on the solid content of the composition.

  2. To measure the contact angle of the above wax and silicone oil to determine the surface energy (OFE) and its polarity and dispersibility components (based on the solids content in the polyacrylate binder specified in the experimental description). 8% by weight wax and / or 1.1% by weight silicone oil were used. This is because it is not possible to carry out direct measurements on pure waxes and pure silicone oils. Refer to the description of the experiment for details on determining the contact angle. Unless otherwise noted, the contact angle of wax and silicone oil means this contact angle. Unless otherwise noted, there is always a waiting time of 3 minutes to achieve equilibrium before measuring any contact angle.

As used herein, “hydrophobic” means that the static initial contact angle after 90 minutes equilibration with water exceeds 90 °.
As used herein, “hydrophilic” means that the static initial contact angle after 90 minutes equilibration with water is 90 ° or less.

The binder preferably has a static initial contact angle of 90 ° or less, more preferably 80 ° or less, and most preferably 75 ° or less after the elapse of an equilibration time of 3 minutes with respect to water.
The wax preferably has a static initial contact angle after the equilibration time of 3 minutes with water of at least 5 ° higher than the static initial contact angle of the binder with water, more preferably at least 10 ° higher.

Preferably, the static initial contact angle after 3 minutes equilibration time for silicone oil water is at least 5 ° higher than the static initial contact angle after 3 minutes equilibration time for water binder, It is preferably 10 ° higher.
The binder generally has a polar component having a surface energy of 10% or more, and particularly preferably has a polar component of 15% or more. The polar component is generally 50% or less.
The binder generally has a dispersant component with a surface energy of less than 90% and preferably has a dispersant component of less than 85%.

The average OFE of the polar component of the binder is preferably 2 to 20 mN / m, and more preferably 4 to 15 mN / m.
The average OFE of the dispersible component of the binder is preferably 20 to 50 mN / m, and 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, and further preferably 30 to 45 mN / m.
The OFE value of the polar component is preferably lowered by adding wax and / or silicone oil. The wax preferably reduces the OFE value of the dispersant component by at least 8%, more preferably by at least 12% compared to a pure binder.

The reduction of the OFE value of the polar component of the binder by adding wax and / or silicone oil is preferably at least 2 mN / m, more preferably at least 4 mN / m, and even more preferably 6 mN / m.
The wax preferably has a polar component having the OFE value of 10% or less, and more preferably 8% or less.

The wax has a dispersible component of the OFE value generally greater than 90%, preferably greater than 92%.
The average OFE of the polar component of the wax is preferably 0.1 to 6 mN / m, more preferably 0.5 to 4 mN / m.

The average OFE of the wax dispersant component 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, and still more preferably 29 to 38 mN / m.

The silicone oil preferably has a polar component having the OFE value of 8% or less, and more preferably 6% or less.
Silicone oils generally have more than 90%, preferably more than 92%, of the above-mentioned OFE dispersible component.

The average OFE of the polar component of the silicone oil is preferably 0.1 to 5 mN / m, and more preferably 0.5 to 3 mN / m.
The average OFE of the dispersant component 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, and even more preferably 30 to 46 mN / m.
By using the composition according to the invention, regions with a high OFE value and regions with a low OFE value will be present on the surface. These values are determined by different polar and / or dispersive components with high and low OFE values. There are many different types of specific polar components, as shown in the experimental description.

A region with a high OFE usually corresponds to a binder with that OFE value, and a region with a low OFE generally corresponds to a wax with that OFE value.
The OFE of the composition of the present invention is an average of a combination of values measured at least 5 times (water / diiodomethane), and the average value of OFEs (regions with high OFE values and regions with low OFE values) (average OFE) Represent as

Accordingly, the OFE value of the composition of the present invention is preferably at least 1.5 mN / m lower than the binder value, more preferably at least 2 mN / m lower than the binder value, and at least 3 mN lower than the binder value. More preferably, the / m is lower.
The average OFE of the polar component of the composition of the present invention is preferably 1 to 10 mN / m, more preferably 1 to 6 mN / m, and even more preferably 1 to 4 mN / m.

The average OFE of the polar component of the composition of the present invention is preferably at least 2 mN / m lower than the average OFE of the polar component of the binder, more preferably at least 4 mN / m lower than the average OFE of the polar component of the binder. More preferably, it is at least 6 mN / m lower than the average OFE of the polar component.
The average OFE of the dispersant component of the composition of the present invention is preferably 14 to 59 mN / m, more preferably 20 to 50 mN / m, and even more preferably 25 to 40 mN / m.

The average OFE of the composition of the present invention is preferably 15 to 60 mN / m, more preferably 22 to 52 mN / m, still more preferably 27 to 42 mN / m.
The ratio of the dispersible component: polar component in the average OFE of the composition of the present invention is preferably 50: 1 to 1: 1, and more preferably 40: 1 to 2: 1.

The average static initial contact angle of the composition of the present invention after equilibration with water for 3 minutes is preferably 50 ° to 130 °, more preferably 60 ° to 125 °, and still more preferably 70 ° to 120 °.
The static initial contact angle of the composition of the present invention after 3 minutes of equilibration with water is preferably 2 ° to 20 ° higher than the binder value, more preferably 5 ° to 15 ° higher.

The average static initial contact angle of the composition of the present invention after the elapse of 3 minutes of equilibrium with diiodomethane is preferably 40 ° to 60 °, more preferably 45 ° to 55 °.
The initial contact angle after 0 seconds of the composition of the present invention with respect to water is preferably more than 100 °. The contact angle for water decreases more rapidly than the compositions known in the prior art. The contact angle of the composition of the present invention with water is generally 130 ° or less after 0 seconds.

The initial contact angle for water after 30 seconds of equilibration time is preferably at least 4 ° lower and more preferably at least 6 ° lower than the static initial contact angle for water after 0 seconds.
The initial contact angle for water after the elapse of the equilibration time of 3 minutes is preferably at least 8 ° lower than the static initial contact angle for water after 0 seconds, and more preferably at least 10 ° lower.

A surface according to the present invention is applied and first sprayed with 85 g / m ^{2 of} water on a vertically arranged surface, then maintained at 23 ° C. and 50% relative (air) humidity for 30 minutes, then the surface The amount of water above is preferably less than 10% by weight of the initial amount of water, more preferably less than 6.0% by weight. The coating (coating film) is generally formed with a wet layer thickness of 200 μm and then dried at room temperature for 2 days. The surface area to be sprayed is usually 414 cm ² .
A surface placed vertically and coated with the composition according to the invention is immersed in water for 1 second and after 30 minutes at 23 ° C. and 50% relative (air) humidity, the surface moisture content is first applied. It is preferable that it is less than 3.0 mass% of the quantity of the water which carried out, and it is still more preferable that it is less than 2.5 mass%. The coating is generally formed with a wet layer thickness of 200 μm and then dried at room temperature for 2 days. The surface area to be sprayed is usually 414 cm ² .

The binder may be a general binder such as those known in the field of coatings and paints. Preferred binders are acrylic and / or methacrylic acid, itaconic acid and acid esters (eg ethyl acrylate, butyl acrylate); homopolymers of styrene, substituted or unsubstituted vinyl chloride, vinyl acetate, acrylamides and acrylonitrile. Polymers, copolymers or terpolymers; water-dilutable alkyd polymers, (meth) acryl / alkyd polymer combinations, polyvinyl alcohol, and mixtures thereof.
Particularly preferred are homopolymers or copolymers of acrylic acid and / or methacrylic acid.

The silicone oil preferably comprises mainly hydrocarbon side chains, such as C _{1 to} C ₂₀ hydrocarbon side chains, more preferably alkyl side chains (eg, C _{1 to} C ₂₀ alkyl side chains). Due to the absence of polar side chains, the silicone oil will have a strong non-polarity. The alkyl chain generally contains 5 or fewer carbon atoms. Particular preference is given to branched or straight-chain polysiloxanes with methyl, ethyl or propyl side chains.
The “mainly non-polar side chain” in the present specification means that no polar side chain is intentionally introduced in the process of synthesizing the silicone oil.

In the present specification, “mainly hydrocarbon side chains” mean that side chains other than hydrocarbons are intentionally not introduced at all in the process of synthesizing silicone oil.
The “mainly alkyl side chain” in the present specification means that no side chain other than the alkyl side chain is intentionally introduced at all in the process of synthesizing the silicone oil.

And conditions for the hydrocarbon side chain of C ₁ to _{C 20,} the conditions for the alkyl side chains of _{C 1} to _{C 20,} is the same.
In a preferred embodiment, the silicone oil contains only hydrocarbon side chains, more preferably only alkyl side chains according to any one of the above embodiments.

Silicone oils preferably do not have alkoxy side chains. The lack of alkoxy side chains can be confirmed by the lack of symmetrical Si—O—C stretching vibrations in FTIR spectral measurements (940-970 cm ⁻¹ ).
The silicone oil preferably has a molecular weight of 1000 to 20000 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 of the present invention preferably contains only a silicone oil having the above properties or preferred embodiments thereof.
As already mentioned, silicone oil appears to have the effect of leading to a non-uniform distribution of wax and binder on the surface, i.e. preventing flow. This effect is included in one of the reasons for the effect of the present invention. In contrast, many silicone compounds, such as wetting agents made from silicone as well, have the effect of promoting flow. This promoting effect is generally achieved by a structure including a surfactant.

Regarding the volume concentration of the pigment, the composition is preferably 30% to 55%, more preferably 35% to 50%. The wax preferably has a melting point in the range of 80 ° C to 160 ° C. Waxes usually do not contain silicone.
Examples include natural waxes (eg beeswax, carnauba wax and paraffin waxes) and synthetic waxes (eg polyalkylene waxes, polyamides, oxidized polyalkylene waxes, ethylene and acrylic and / or acrylates low Molecular copolymer waxes). Polyethylene or polyamide waxes are particularly preferred, and polyethylene waxes are most preferred. When more than one type of wax is used, the amount and temperature information refers to the value of the wax as a whole. However, it is preferable to use only one kind of wax.

The mass of the wax is preferably 0.2 to 5% by mass relative to the solid content of the composition.
The amount of the silicone oil is preferably 0.1 to 1.5% by mass based on the solid amount of the composition of the present invention, more preferably 0.2 to 1.0% based on the solid amount of the composition of the present invention. % By mass.

The pigments and / or fillers are preferably pyrogenic silicic acid, precipitated silicic acid, silicon-aluminum mixed oxides, carbonates (eg alkaline earth metal carbonates such as calcium carbonate), silicon dioxide, silica. Acid salts (eg, aluminosilicates), sulfates (eg, barium sulfate), titanium dioxide, colored pigments (eg, iron oxides, bismuth vanadate), or mixtures thereof. Particularly preferred are titanium dioxide, silicates, and carbonates.
In some embodiments, the pigment and / or filler consists of an inorganic pigment and / or an inorganic filler.

The amount of pigment and filler is preferably 35 to 50% by weight, based on the solids content of the composition. The above amount is a value based on the sum of the pigment and the filler.
The particle diameter of the pigment and filler is generally in the range of 0.1 to 100 μm, preferably 0.2 to 50 μm.

The composition of the present invention may further contain conventional additives up to an amount of up to 8.0% by mass, preferably up to 5.0% by mass, based on the solid content of the composition. Examples are dispersants, thickeners, wetting agents, biocides, defoamers and others.
The composition of the present invention is preferably a molding or coating composition, more preferably a paint or a plaster.

The composition of the present invention may be in the form of an aqueous dispersion. In the case of an aqueous dispersion, the amount of water is preferably 20 to 60% by weight. The composition according to the present invention may be a dispersion of one kind or two or more kinds of organic solvents. Such organic solvents are aliphatic or aromatic hydrocarbons such as toluene, alcohols, esters, or ketones. These are known as binder and paint solvents. In the case of an organic solvent dispersion, the proportion of the solvent is preferably 20 to 50% by mass.
Alternatively, the composition according to the present invention may be a dispersion of a mixture of water and the organic solvent.

The amount of water or organic solvent added depends on the intended use by those skilled in the art. In the case of a dispersion of a mixture of water and the above organic solvents, the amount of water is preferably more than 50% by mass with respect to the total amount of water and the organic solvent.
The present invention is also useful for a coating on the surface of a substrate. This coating is
Hydrophobic wax,
Silicone oils containing mainly non-polar side chains, and hydrophilic binders,
Pigments and / or fillers,
The composition comprises a pigment at a concentration of 25% to 60% by volume (or mass%), preferably at a concentration of 35% to 55% by volume.

The coating is preferably
0.1 to 10% by weight of a hydrophobic wax;
0.01 to 2% by weight of silicone oil;
10 to 60% by weight of hydrophobic binder; and 30 to 80% by weight of pigment and / or filler (this amount is based on the total amount of pigment and filler)
including.
The coated material is preferably in an uncured state.

Preferred embodiments of the composition according to the invention are also preferred embodiments of the coating according to the invention.
The substrate is preferably a wall and is an external surface that is exposed to outdoor exposure. For example, the outer surface (facade) of a building is more preferable.

[Measuring method]
(Melting point of wax)
According to ISO EN 11357-3.
(Contact angle and surface energy, and their polar and dispersive components)
For contact angles, water and diiodomethane were used as test substances. The droplet sizes were 2 μL to 4 μL, respectively.
Under certain conditions, direct measurement of the wax surface is not possible. That is, as the wax hardens, the wax precipitates as crystals, which makes measurement impossible. The same applies when the wax is too soft. Therefore, a mixture of 3.85% by weight of wax and 96.15% by weight of the binder listed below was prepared per solid, and a corresponding coating was prepared. The contact angle was measured on the surface.

Silicone oils are generally viscous liquids, so direct measurement on their surfaces is generally not possible. Accordingly, a mixture of 1.13% by mass of silicone oil and 98.87% by mass of the binder listed below was prepared per solid, and a corresponding coating was prepared. The contact angle was measured on the surface.
The aqueous dispersion had a solids content of 46% by weight and was obtained by using a copolymer of alkyl acid and methacrylic acid ester as a binder. The copolymer has a Brookfield viscosity according to DIN EN ISO 2555 (Spindel 4; 20 rpm; 23 ° C.) of about 7000 mPa · s and is available as Celanese Mowilith LDM 7724.

The static contact angle was measured under conditions of 23 ° C. and 50% relative humidity after drying for 2 days. After applying water droplets and / or diiodomethane droplets, the measurement was carried out after waiting for 180 seconds.
The contact angle was measured using a Cruz contact angle measuring device G1 based on a three-phase contact line between solid, liquid, and gas. At least 5 drops were measured at different locations on each specimen.

The surface energy was measured according to the Owens-Wendt-Rabel-Kaelble method as described below (obtained from Cruz).
According to Owens-Wendt-Rabel-Kaelble, the surface tension of each phase can be separated into polar and dispersive components.

  In the Owens-Wendt method, the interphase tension is based on the following equation:

  Furthermore, it combines with the following Young's equation.

  The two founders of the above method solved the equation based on the contact angles of two liquids having a dispersive component and a polar component known for surface tension. The equations of Equation 3 and Equation 4 are combined, and the obtained equation is rearranged and applied to a general linear equation.

  The applied equation is shown below.

In a linear retrograde plot of y against x, σ _s P is thus obtained from the square of the slope of the straight line m and σ _s D is obtained from the square of the ordinate intercept b.

  The surface energy is given as mN / m.

(Volume concentration of pigment)
The volume concentration of the pigment (EN ISO 4618-1) indicates the volume ratio of the pigment / filler to the binder in the coated film. Additives were also included in the formulation, but they were not included in the calculation. Solvent and water are also excluded because they are no longer present in the cured film. Even if wax and silicone oil are present, they are not included in the calculation.

(Viscosity of silicone oil)
According to DIN 53015.

(FTIR (lack of symmetric Si—O—C stretching vibration))
Measurements were performed using a Perkin-Elmer Spectroscopic 100 FTIR spectrometer fitted with a universal ATR accessory. The lack of symmetrical Si—O—C stretching vibration at 940-970 cm ⁻¹ indicates the lack of alkoxy side chains.

[Substance used]
(binder)
The aqueous dispersion had a solids content of 46% by weight and was obtained from a copolymer of alkyl acid and methacrylic acid ester. The copolymer has a Brookfield viscosity according to DIN EN ISO 2555 (Spindel 4; 20 rpm; 23 ° C.) of about 7000 mPa · s and is available as Celanese Mowilith LDM 7724.
(Inorganic pigment)
Titanium dioxide (average particle size: less than 1μm)

(Inorganic filler)
Calcium carbonate (average particle diameter: D ₅₀ = 2.5 μm)
(Magnesium silicate)
Aluminum silicate (average particle diameter: D ₅₀ = 25 μm)

(wax)
A polyethylene wax having a melting point, a density of 0.98 g / cm ³ , and a viscosity of 40 mPa · s (DIN 53019 1.921 s −1) in the range of 100 ° C. to 110 ° C. was used. The solid content of the dispersion was 35% by mass.
(Silicone oil)
Dimethylpolysiloxane having a viscosity of 90 mm ² / s and a molecular weight of 6100 g / mol and containing no alkoxy groups was used.

First, a mixture of pure binder and wax and / or silicone oil was examined. To that end, the compositions shown in Table 1 were applied with a wet layer thickness of 200 μm and dried as explained above. After 3 minutes equilibration time, the contact angle of the droplets on the surface was measured for water and diiodomethane. Dispersibility (DA) and polar (PA) components were also measured for OFE and OFE.
The mass of PE wax in Table 1 is a value relative to an aqueous dispersion having a solid content of 35% by mass, and the mass of the binder refers to the aqueous dispersion having a solid content of 46% by mass. Silicone oil is in a pure compound state.

This result shows a reliable increase in the contact angle of water when wax and / or silicone oil is added.
Furthermore, the following compositions were prepared, and the contact angle, OFE, and the polarities and dispersibility components of the coatings obtained for OFE were measured (amount: mass%).

Water 10.0
Acrylate binder dispersion (solid content: 46% by mass) 43.0
Titanium dioxide 14.0
Filler (silicate / carbonate) 24.0
Additives (dispersants, thickeners, antifoaming agents, biocides, etc.) 3.5
PE wax dispersion (solid content: 35% by mass) 5.0
Dimethylpolysiloxane 0.5

The resulting coating had 40% PVK.
Furthermore, the pigment and filler components were changed to obtain compositions with PVK of 30, 50, and 60. The results are shown in the table below.

The polar component of the binder is 8.0 mN / m or 19.8%.
There is a noticeable improvement in wetting behavior between 40% PVK and 50% PVK. The result drops again at 60% PVK. In this regard, it is estimated that large amounts of pigments and fillers have an effect.

(Contact angle dynamics (water))
As will be shown below, in the formulation of the paint according to the present invention, the change in the contact angle with the passage of time occurs more rapidly than in the comparative example. Furthermore, the contact angle difference at 180 seconds is larger than the contact angle difference at 0 seconds.
To that end, the PVK = 40% paint formulation in the above example was used, where the wax and silicone components were changed as shown in Tables 3a-3d below. As described above, the amount of the wax is a value based on the dispersion having a solid content of 35% by mass.

The process of decreasing the contact angle with time is shown in FIGS.
FIG. 1 shows the measurement results for the composition of Reference Example 1 + 0% wax + 0% silicone oil.
FIG. 2 shows the measurement results for the composition of Reference Example 2 + 4.5% wax + 0% silicone oil.
FIG. 3 shows the measurement results for the composition of Reference Example 3 + 0% wax + 0.5% silicone oil.
FIG. 4 shows the measurement results for the composition of Reference Example 4 + 4.5% wax + 0.5% silicone oil.

As shown in the above measurement results, the formulation of the present invention not only has a higher contact angle at 0 seconds, but also a decrease in contact angle after 180 seconds is 12 ° or more. Is larger than the reference example. Furthermore, a certain decrease in the contact angle occurs in the first 30 seconds.
The composition according to the invention also has a rapid re-drying of the surface.
This became clear based on the following experiment.

A PVC film with a wet layer thickness of 200 μm was prepared and dried at room temperature for 2 days. The surface area was 414 cm ² .
The coated PVC film was suspended and its own weight was measured. Next, about 3.5 g of water was sprayed there from a distance of about 35 cm. Re-drying was observed for 30 minutes and the weight was recorded every 5 minutes. The test was carried out in a standard climate of 23 ° C./50% relative humidity.

Instead of the 5.0% by weight wax dispersion, the composition PVK40 according to the invention described above was used except that a 4.5% by weight wax dispersion was used (see IE3 below).
IE3 was compared with Reference Example 1 and Reference Example 2. Comparative Example 1 is a highly hydrophobic coating and has a contact angle with water of 125 ° after an equilibration time of 3 minutes. Reference Example 2 has a hydrophilic surface obtained from the outer surface (facade) paint of a conventional dispersion silicate that does not contain a hydrophobizing agent. Reference Example 2 appears to be dry visually after about 15 minutes. However, as shown in the measurement results, the coating contains a considerable amount of water.

FIG. 5 (mass / hour) and FIG. 6 (mass% / hour) show a plot of the amount of water remaining on the surface per hour.
Furthermore, the coating material defined above was completely immersed in water for 1 second and further suspended on a balance for 5 seconds.
Re-drying was observed for 30 minutes and the weight was recorded every 5 minutes. The test was carried out in a standard climate of 23 ° C./50% relative humidity.

FIG. 7 (mass / hour) and FIG. 8 (mass% / hour) show a plot of the amount of water remaining in or on the surface layer per hour.
The measurement of water uptake is according to EN 1062-1 and -3 (value of W: permeability to water).
From this property, the resistance to penetration of the coating and water uptake can be evaluated.

Reference example 1
0.05kg / (m ² · h ^0.5 ) Class W3
IE3
0.02 kg / (m ² · h ^0.5 ) Class W3
Reference example 2
1.17kg / (m ² · h ^0.5 ) Class W1

Claims (14)

Hydrophobic wax,
Silicone oils containing mainly non-polar side chains, and hydrophilic binders,
A composition comprising a pigment and / or a filler,
A composition comprising a pigment at a concentration of 25% to 60% by volume.   The composition according to claim 1, wherein the static initial contact angle after the equilibration time of 3 minutes for the wax to water is at least 5 ° higher than the static initial contact angle for the water of the binder for 3 minutes after equilibration. .   Composition according to claim 1 or 2, wherein the wax has a polar component with a surface energy of 10% or less.   4. A composition according to any one of claims 1 to 3 wherein the wax reduces the surface energy of the polar component by at least 8%.   A composition according to any one of the preceding claims, wherein the silicone oil mainly comprises hydrocarbon side chains.   A composition according to any one of the preceding claims, wherein the silicone oil has an average molecular weight of 1000 to 20000 g / mol. Any one of the compositions according to claim one of claims 1 to 6 the silicone oil has a viscosity of 75 to 135mm 2 / ^s.   A composition according to any one of the preceding claims, wherein the volume concentration of the pigment is from 30% to 55% by volume.   A composition according to any one of the preceding claims, wherein the wax is a polyethylene wax or a polyamide wax.   10. A composition according to any one of claims 1 to 9, wherein the composition is a molding composition or a coating composition.   A composition according to claim 10 wherein the composition is a paint or plaster. Hydrophobic wax,
Silicone oils containing mainly non-polar side chains, and hydrophilic binders,
Pigments and / or fillers,
A coating on the surface of a substrate wherein the composition contains a pigment at a concentration of 25% to 60% by volume.   10. A method of using the composition according to any one of claims 1 to 9 as a molded product or a coated product.   Use according to claim 13, wherein the molding or application is a paint or plaster.

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