WO2010094701A1

WO2010094701A1 - Composition and paint for regulating the room humidity in buildings

Info

Publication number: WO2010094701A1
Application number: PCT/EP2010/051976
Authority: WO
Inventors: Manfred Weber; Lutz Hippe; Beate GÜNTHER; Brigitte Kaltofen; Burkhard Eipel; Horst Donth
Original assignee: Velind Chemie Gmbh & Co Kg
Priority date: 2009-02-17
Filing date: 2010-02-17
Publication date: 2010-08-26
Also published as: EP2398749A1; DE102009000916A1

Abstract

The invention relates to a paint for automatically regulating the room humidity in buildings, the paint comprising pigments, binders, water as a diluent, fillers, and at least one auxiliary agent selected from among dispersant, defoamer, thickener, preservative, wetter, solvent, and pH-regulating agent and being characterized in that the paint contains silica gel or silica gel in combination with activated aluminum oxide and inorganic or organic binders, the silica gel having a main amount of a pore volume and a maximum of the pore volume in the range of 20 to 200 Å pore diameter, and the binders being water-dispersible or water-soluble and water-vapor-permeable.

Description

Composition and coating to regulate indoor humidity in buildings

The invention relates to a composition and a coating comprising this composition for application to substrates in

Buildings and the use of the composition or paint to automatically regulate indoor humidity. The paint is understood in the context of the invention, a technical coating, which is applied as a liquid to pasty coating material mainly by brushing or rolling on surfaces in buildings.

The description of indoor climate in people's lounges includes data on temperature, relative humidity and air pollution in the form of dust and in the form of gaseous pollutants.

While attempts are made to tackle air pollutants using specific methods because they are found only in special room conditions, temperature and relative humidity are fundamental conditions for the well-being of the users of these premises. Moreover, these two data are also directly related.

Control of the temperature over the amount of heat added or removed is technically satisfactory solved.

The control of relative humidity is currently done discretely by supplying or removing water vapor from the room air by evaporation or condensation, under controlled use of electrical energy and for the necessary air circulation. Unregulated processes (evaporators or hygroscopic salts) work only in one direction and with unsatisfactory success in terms of cost, ecology and effectiveness.

The use of silica gel and of alumina molded bodies is known as a dry agent. They are used in particular for gas drying and by regenerated thermal desorption of the absorbed water vapor. Furthermore, silica gels are used for room drying in air conditioning systems in insulating glass elements and in packages of moisture-sensitive goods. In addition, they also serve to dry the air in assembly, storage and factory rooms. The application is carried out by setting up suitable containers containing the silica gel as bulk material.

Silica gels with different pore volumes are also often used to dry liquids.

However, it has been shown that a stable and rapid change in the room air humidity is not possible by an introduced into the rooms bulk amount of silica gel or alumina, especially if by leaving and entering the premises again and again changed moisture content of the air.

It was therefore the task of developing a composition that makes it possible to effect an automatic regulation of the indoor air humidity, without additional energy would be required and without polluting conditions.

The object is achieved in accordance with the invention with a composition comprising silica gel or silica gel in combination with activated alumina and inorganic or organic binders which are water-dispersible or water-soluble and permeable to water vapor, wherein the silica gel has a major amount of pore volume and a maximum pore volume in the range 20 to 200 A pore diameter, preferably from 20 to 120 A, more preferably from 30 to 100 A.

In addition, the object has been achieved by a coating, in particular an emulsion paint, which have the composition according to the invention. The paint of the invention comprises pigments, binders, water as a diluent, fillers and at least one adjuvant selected from dispersants, defoamers, thickeners, preservatives, wetting agents, solvents and pH-adjusting agent and is characterized in that it contains silica gel or silica gel in combination with activated alumina and inorganic or organic binder, wherein the silica gel, a majority of a pore volume and a Maximum of the pore volume in the range of 20 to 200 A pore diameter, and the binders are water-dispersible or water-soluble and water vapor permeable. The silica gel according to the invention preferably has a major amount of a pore volume and a maximum pore volume of from 20 to 120 A pore diameter, more preferably from 30 to 100 A.

Surprisingly, it has been found that the paint according to the invention with the silica gel according to the invention considerably reduces the fluctuation range of the room air humidity. If silica gel is used in combination with activated aluminum oxide in the paint according to the invention, then the speed of absorption and the release of moisture are also markedly improved. Despite the added binders, the pores of the silica gel or of the activated aluminum oxide are obviously not closed.

The silica gel used in the composition according to the invention or in the paint according to the invention is prepared by known processes as follows: a) Preparation of an unstable silica hydrosol, e.g. B) gelation of the hydrosol, c) comminution of the resulting hydrogel, d) post-treatment with ammonia solution with constant homogenization for pore setting, e) separation of the ammoniacal aftertreatment liquid to a maximum of 50 wt .-% or no separation of ammoniacal after-treatment liquid and f) drying under constant homogenization. This method is described for example in DE 30 33 982 A1, claim 1 and the embodiments 1 and 2. It is excluded according to the invention that the composition or the paint contains colloidal SiO 2. Likewise, the composition or the paint contains no aluminosilicates or clay or clay-containing materials.

The active aluminum oxide used in the composition according to the invention or in the paint according to the invention is an aluminum oxide with about 90% by weight Al 2 O 3 and preferably a specific surface area of from 200 to 300 m ² / g. In addition to about 0.25 wt .-% Na ₂ O, it may contain traces of CaO and Fe ₂ Os. It is preferably γ-alumina. Such an active alumina is commercially available, for example under the trade name "Compalox ^®" ANA / company Martin GmbH, Bergheim, Germany.

The paint according to the invention, which is in particular a dispersion wall paint, comprises, in addition to the constituents according to the invention, the components customary for paints, preferably pigments and / or dyes, water as diluents, binders and fillers and optionally adjuvants, so-called additives, which serve to improve the technical properties. Such auxiliaries are, for example, dispersants, defoamers, thickeners, preservatives, wetting agents, solvents, pH regulators. The paint of the invention contains at least one of these auxiliaries, but preferably dispersants, defoamers, thickeners, preservatives, wetting agents and pH-regulating agent, wherein for each of these functional components according to the invention not only an ingredient, but also various ingredients in the paint be present can. In other words, it would be possible, for example, to contain three different thickeners or a thickener, although the claim merely identifies "thickeners".

In the paint of the present invention can be used as dispersants the usual known for the dispersion of mineral pigments, for. Polyacrylate ammonium salt (Ecodis ™ 80 ex Coatex, Ine, France). As fillers in the coating according to the invention preferably calcium carbonate, silicates, such as As magnesium silicate, quartz, chalk or mixtures thereof in question. As thickening agents come within the meaning of the invention, for example, cellulose derivatives, such as hydroxyethyl cellulose, acrylic polymers or polyurethanes such. For example, those of COAPUR ^® series of Coatex, Inc., France in question.

Advantageous embodiments of the invention are specified in the subclaims.

An advantageous embodiment is characterized in that, for example, slaked lime is contained as a water vapor permeable inorganic binder. As a water vapor-permeable organic binder according to the invention, the natural binder, such as glue or varnish, in

Question. As a water vapor-permeable organic synthetic binder z. As synthetic resins, such as vinyl derivatives, preferably polyvinyl acetate, or z. As acrylates or their copolymers may be included with styrene.

A development of the composition according to the invention is characterized in that silica gel and activated alumina are contained with a particle size in the size range of 5 to 10,000 microns, preferably from 10 to 1000 microns.

An advantageous embodiment provides that the proportion of silica gel or silica gel and activated alumina in the composition is in the range of 2 to 70% by mass, preferably 5 and 30% by mass. In the total weight of the paint, the proportion of silica gel or silica gel and activated aluminum oxide is in particular 2 to 30 wt .-%, preferably 5 to 20 wt .-%, particularly preferably 7 to 10 wt .-%. The proportion of activated alumina based on the silica gel / alumina mixture is preferably 8 to 12 wt .-%. The proportion of the water vapor-permeable binder in the total weight of the paint is preferably 6 to 20% by weight, particularly preferably 8 to 15 wt .-%. The proportion of water is preferably on the total weight of the paint 20 to 40 wt .-%, particularly preferably 25 to 35 wt .-%.

The invention is further characterized by the use of the composition according to the invention and the paint according to the invention for the automatic regulation of the indoor air humidity in buildings, wherein the composition or the paint on the walls, ceilings or floors of the rooms applied or incorporated flat or in or on in the rooms placed moldings introduced or applied.

In a preferred embodiment, the composition according to the invention in plaster or Stuckgipsform body is introduced.

The subject matter of the present invention is thus also a shaped body which has the composition according to the invention or the paint according to the invention.

It is known that silica gels and alumina with special properties are able to absorb or release water vapor to a considerable extent both at a constant temperature only as a function of the ambient relative humidity, but also at a constant relative humidity as a function of the temperature , These special adsorption and desorption properties are already effective in the temperature range between about 15 to 35 ° C, ie in the usual range of human residence. Surprisingly, these properties are significantly enhanced with the composition of the invention or the paint according to the invention. The processes quickly follow the changes in temperature and relative humidity, so that the fluctuation range of the room air humidity is significantly reduced without having to supply energy. In a distribution of the adsorbents according to the invention on walls and / or ceilings of the rooms also eliminates any energy needs for air circulation. Another advantage associated with this self-regulated effectiveness, namely a wear-free operation, that is, only a placement of the adsorbents on ceilings and / or walls already has an automatic climate control in the rooms result.

Such a procedure represents a technical-economic innovation that can be realized using ecologically safe materials.

The invention will be explained in more detail with reference to Figures 1 to 8 and embodiments.

Show it:

1 graphical representation of the texture comparison of three different silica gels according to Example 1,

2 is a graphical representation of the water release of the three different silica gels as a function of the temperature,

3 is a graphical representation of the moisture absorption of various paints (Example 3),

4 is a graphical representation of the thermally induced water release of activated alumina,

Figure 5 is a graphical representation of the humidity and temperature in a room on a rainy day. Comparison of a commercial emulsion paint with the emulsion paint according to the invention (Example 4),

Fig. 6 is a graphical representation of the humidity and temperature in a room on a dry day; Comparison of a commercial Emulsion paint with the emulsion paint according to the invention (Example 4),

7 is a graphic representation of the room temperature and the room air humidity in a living room before renovation with the wall paint according to the invention according to Example 4, (Example 5) and

8 is a graphic representation of the room temperature and the humidity in a living room after the renovation with the inventive wall paint according to Example 4, (Example 5).

The following examples are intended to explain the invention in more detail with reference to the diagrams in FIGS. 1 to 8:

Example 1 :

Three silica gels were prepared according to EP Barret, LG Joyner, PP Halenda "The Determination of Pore Volume and Area Distributions in Porous Substances", J. Am. Chem. Soc. 73, (1951) 373-380 using the "ASAP 2010" measuring device Micromehtics GmbH, Mönchengladbach, Germany, was examined for their pore volume distribution. The inventive silica gel of curve 1 was prepared according to DE 3033982 A1, exemplary embodiment 1. The silica gel of curve 2 is a commercially available silica gel with the trade name "Syloid 622" from GRACE GmbH & Co. KG, Worms, Germany The silica gel of curve 3 with the trade name "Köstropur" from CWK GmbH, Bad Köstritz, Germany, is also commercially available

In Fig. 1, these pore volume distributions in cm ³ / g / angstrom are plotted against the pore diameter in angstrom units. Logarithmically plotted on the abscissa is the pore diameter of the silica gels in Angstrom units. Plotted on the ordinate is the differential ratio of pore volume (Dv in cm ³ ) to mass (Dd in g) (Dv / Dd) per Angstrom unit. Curve 2 shows the silica gel with the highest pore volume and curve 3 shows the silica gel with the smallest pore volume. A maximum of the pore volume distribution is absent.

It has been found that the pore volume distribution of the silica gel according to curve 1 has the most advantageous pore volume distribution for the solution according to the invention.

All three silica gels were stored under identical external conditions at room temperature for 24 hours over water and thereby saturated with water vapor.

The water-saturated silica gel types according to curves 1, 2 and 3 were then heated on a thermobalance at 5 ° C / minute to thermally desorb the absorbed water vapor. In this way, their maximum water vapor capacity was determined.

As shown in FIG. 2, the silica gel according to curve 1 is surprisingly clearly superior to the two other silica gels in the water vapor capacity.

On the abscissa, the temperature is plotted in ⁰ C. The ordinate shows the weight loss of water vapor in mass%.

Example 2:

As shown in FIG. 4, the activated aluminum oxide according to the invention surprisingly also has an acceptable water vapor capacity and is therefore well suited even for use as a climate regulator alone or in combination with the silica gel according to the invention. The ordinate indicates the loss of water in mass%, which the steam saturated activated alumina experiences at the respective temperature (plotted on the abscissa in ⁰ C).

Example 3:

The performance of a climate-regulating paint according to the invention (curve 1), which was applied as a wall paint on a wallpaper is shown in comparison with the non-inventive compositions of the curves 2 and 3 in Fig. 3.

Plotted on the abscissa is the amount of water in g, which was added in vapor form and continuously to the climate chamber. The ordinate shows the resulting water vapor content of the air space in% relative humidity at constant temperature.

A commercially available wall paint (HORNBACH wall and ceiling paint for white, matt interior coatings, product code: M-DF01) painted onto a wallpaper was subjected to a continuous increase in water vapor in a climatic chamber at 24 ° C. At the same time, the relative humidity in the room air was measured (curve 3).

In the same way, a coating according to the invention, consisting of the same wall paint but with the addition of 10% by weight, based on dry mass, of the silica gel according to the invention was prepared and loaded with water vapor as a wallpaper spread in the climatic chamber (curve 1).

Likewise, 10% by mass of the silica gel were stirred according to curve 2 in the same commercial color, the mixture was also spread on wallpaper and applied under identical conditions with steam (curve 2). As FIG. 3 shows, the coating according to the invention is able to absorb considerably more water vapor, in particular at the higher partial pressures of water vapor. These absorbed amounts of steam can then be returned to the room air with decreasing relative humidity and ensure the comfort limits.

It is also clearly recognizable that the coating which contains the non-inventive silica gel according to curve 2 differs only insignificantly from the silica gel-free wall paint.

Example 4:

For the production of a wall paint according to the invention, the following raw materials were used and intensively mixed with one another:

Table 1

Example formulations of an inventive

Dispersion paint inside for laboratory and pilot plant approach

With this emulsion paint according to the invention the ceiling and walls of a living room were painted and used for comparison, another living room, which was painted with commercial emulsion paint (HORNBACH wall and ceiling paint for white, interior matt, product code: M-DF01), the differs from the dispersion paint of the invention only by the lack of silica gel / alumina.

In both rooms, the air humidity was measured over a period of 24 hours and recorded by a data collector.

Figures 5 and 6 show the effects of a rainy day and a very dry day.

The dispersion paint according to the invention containing 7.8 mass% of silica gel (based on the total weight of the paint) containing the silica gel according to curve 1 shows in comparison to the effect of the same wall paint without silica gel (curve 2) the advantageous effect on the room air humidity. The corresponding relative humidity is plotted on the right ordinate.

The left ordinate shows the room temperature in ⁰ C, the curve of which traces curve 3 over time (abscissa in h).

On the rainy day (FIG. 5), it can be clearly seen that the dispersion paint according to the invention brings about a reduction in the spatial humidity and thus a substantial improvement in the room climate compared with the traditionally coated comparative space.

On a dry day (FIG. 6), the stored moisture of the paint according to the invention is released to the room air and the air humidity is significantly raised compared to the reference space. Example 5:

The wall paint of Example 4 according to the invention was used for the renovation of a living space.

For a whole month, room temperature and humidity were measured and recorded continuously before renovation. Fig. 7 shows the left ordinate with the temperature in ⁰ C, the time course is shown with the temperature curve.

The associated room humidity shows the curve of the rel. Humidity, the amount of which is plotted on the right ordinate.

The abscissa shows the time in the form of the (measurement) date.

In the same way, after the renovation, this data was again recorded for a month. Fig. 8 shows on the left ordinate the temperature in ⁰ C for the temperature curve and on the right ordinate the rel. Humidity in% over time, whereby the abscissa contains the respective measurement date as a time expression.

The comparison of the two diagrams clearly shows the effect of the wall paint according to the invention on the room climate:

Before the renovation is a strong fluctuation of the room humidity by the value of about 40% rel. To observe humidity (Fig. 7), which means the lower edge of the feel-good area.

Due to the effect of the wall paint according to the invention, after the renovation (FIG. 8), the fluctuation range of the room air humidity is considerably reduced. The fluctuations themselves are around the value 50% rel. Humidity and thus around 10% higher, which results in a significant improvement in the feel-good climate.

Claims

claims

Composition for controlling the indoor air humidity in buildings containing silica gel or silica gel in combination with activated alumina and inorganic or organic binders which are water-dispersible or water-soluble and water-vapor-permeable, the silica gel having a major amount of pore volume and a maximum pore volume of 20 to 200 A, preferably 20 to 120 A, pore diameter.

2. Paint, in particular emulsion paint, for regulating the indoor air humidity in buildings, comprising pigments, binders, water as diluents, fillers and at least one hydrogen selected from dispersants, defoamers, thickeners, preservatives, wetting agents, solvents and pH-adjusting agent , characterized in that the paint contains a composition according to claim 1 of silica gel or silica gel in combination with activated alumina and inorganic or organic binders, wherein the silica gel is a major amount of pore volume and a maximum pore volume of 20 to 200 A, preferably 20 to 120 A,

Pore diameter, and the binders are water-dispersible or water-soluble and water vapor permeable.

3. paint according to claim 2, characterized in that silica gel and / or activated alumina are contained with a particle size of 5 .mu.m to 10,000 .mu.m, preferably from 10 .mu.m to 1,000 .mu.m.

4. paint according to claim 2 or 3, characterized in that as active alumina gamma-alumina is included.

5. A paint according to any one of claims 2 to 4, characterized in that as water vapor permeable and water-dispersible or water-soluble organic binder, natural binder, preferably glue or Varnish, or synthetic resins, preferably acrylates or polyvinyl acetate, are included.

6. Paint according to one of claims 2 to 5, characterized in that the proportion of silica gel or of silica gel and activated alumina on

Total weight of the coating 2 to 30 wt .-%, preferably 5 to 20% by weight, particularly preferably 7 to 10 wt .-%, wherein preferably the proportion of activated alumina based on the silica gel / alumina mixture 8 to 12 wt .-% is.

7. Paint according to one of claims 2 to 6, characterized in that the proportion of the water vapor-permeable binder in the total weight of the paint 6 to 20 wt .-%, preferably 8 to 15 wt .-% is.

8. Paint according to one of claims 2 to 7, characterized in that as pigments titanium dioxide and / or color pigments are contained.

9. paint according to any one of claims 2 to 8, characterized in that dyes are included.

10. Paint according to one of claims 2 to 9, characterized in that the proportion of water in the total weight of the paint 20 to 40 wt .-%, preferably 25 to 35 wt .-% is.

11. Use of a composition according to claim 1 or a paint according to any one of claims 2 to 10 for regulating the humidity in the room.

12. Use according to claim 11, characterized in that the composition or the paint applied to the walls, ceilings or floors of the rooms or incorporated in or on or in the

Chambers placed moldings introduced or applied.

13. Use according to claim 11, characterized in that the composition is introduced into plasters.

14. Use according to claim 11, characterized in that the composition is introduced into Stuckgipsform body.

15. A shaped article comprising a composition according to claim 1 or a paint according to any one of claims 2 to 10.