DE202015100097U1 - Dehumidifying plaster for the coating of building walls and / or building ceilings - Google Patents

Abstract

Dehumidifying plaster (8) for the coating of building walls (2), in particular building interior walls (6), and / or building ceilings, comprising a mixture of cement or lime, water, and an additive, characterized in that the mixture additionally comprises wood fibers ,

Description

The present invention relates to a dehumidifying plaster for the coating of building walls, in particular of building interior walls, and / or building ceilings.

In building walls and ceilings, the problem of mildew and salt efflorescence occasionally occurs, especially in old buildings, where much moisture is contained in the building walls and the building ceilings and re-penetrates. Such mold growth and salt efflorescence permanently damage the building walls and the building ceilings and also pose a health risk.

The DE 28 14 317 C suggests a dehumidifying plaster and an additive for this, which gives the plaster the property to suck water from the moistened masonry and to direct this water or the resulting water vapor quickly through the plaster thickness and leave on the outside to the environment, so that the wall surface allegedly always is dry.

Although this additive and this dehumidifying plaster show good results, cracks in the plaster can form in such a dehumidifying plaster in particular by temperature fluctuations occurring. There is also a demand for dehumidifying plaster, which removes or regulates the moisture from building walls and / or building ceilings even more effectively.

It is therefore an object of the present invention to provide a dehumidifying plaster which can reliably prevent cracking due to temperature fluctuation and at the same time further increase the moisture releasing ability and the humidity regulating ability.

This object is achieved by the subject matter of the independent patent claim. Advantageous developments emerge from the dependent claims.

An inventive dehumidifying plaster for the coating of building walls, in particular building interior walls, and / or building ceilings, comprises a mixture of cement or lime, water, and an additive, and is characterized in that the mixture additionally comprises wood fibers.

According to one of the underlying realization of the invention, the air inclusions contained in the dehumidifying plaster are decisive for the ability of the dehumidifying plaster to give the present in this building / building ceiling and / or emerging moisture by diffusion and thereby dry out the plaster layer.

In accordance with one aspect of the invention, the addition of wood fibers to a dehumidifying plaster base mix of cement or lime, water and an admixture can achieve an optimum amount of air entrapment within the dehumidifying render for this capability, thereby providing improved breathability Moisture results.

According to a further basic idea of the invention, the addition of wood fibers to the dewatering plaster base mixture also reduces the formation of cracks due to temperature fluctuations occurring at the plaster layer. This finding was surprising in that a person skilled in the art would refrain from adding wood fibers, which are basically combustible, to such a dehumidifying plaster to be used, in particular indoors, for reasons of fire safety. However, it has been found in experiments that the wood fibers have only a negligible combustibility by the connection with the dehumidifying plaster base mixture.

The building wall / building walls, in particular building interior wall / building interior walls, and the building ceiling (s) on which / which the dehumidifying plaster according to the invention is applied, can be of any type, as long as they form / form a load-bearing plaster base. The dehumidifying plaster according to the invention is suitable for all masonry that forms a stable plaster base, including brick, concrete, Ytong, etc.

In general, such a dehumidifying plaster can be used both outdoors and indoors. However, the application to building interior walls and / or internal building ceilings is particularly advantageous.

Furthermore, the dehumidifying plaster according to the invention is particularly suitable for the coating of building walls, in particular building interior walls and building ceilings in which a substantial proportion of moisture in the walls and / or ceilings is present or z. B. occurs as a result of insufficient insulation, especially old buildings with wet walls and / or ceilings.

The dehumidifying plaster according to the invention has an even higher degree than that in the DE 28 14 317 proposed dehumidifying plaster the ability to remove moisture from building walls and / or building ceilings on its not with the building wall / building ceiling related side, which forms the respective inner side in building interior walls and internal building ceilings, to the environment, ie when applied to building interior walls and internal building ceilings, in the interior of the room.

In addition to the moisture-dispensing function and thus the moisture-regulating function of the dehumidifying plaster according to the invention also has a Dämmungsfunktion, in particular a heat and sound insulation function.

The dehumidifying plaster according to the invention thus prevents the formation of mildew and thus the formation of salt efflorescence, which otherwise usually occurs at the surfaces to the surroundings, when using a plaster without dehumidifying function in the interior, ie at the inside of the building wall and the ceiling inside, and at the boundary surfaces arise between the building wall / building ceiling and plaster layer.

An inventive dehumidifying plaster is therefore very well suited for the renovation of old buildings, in the walls and ceilings moisture is contained and penetrates, for example by rain, heavy rain or driving rain, by rising capillary moisture from the Baufundament, by penetrating microscopic moisture or condensation.

The dehumidifying plaster according to the invention thus forms a breathable plaster, which is particularly suitable for damp and saline masonry.

According to a first embodiment of the invention, the proportions of cement or lime, water, additives and wood fibers in the dehumidifying plaster are as follows:
Cement or lime: 60-70% by weight, in particular 62-67% by weight,
Water: 25-35% by weight, in particular 29-32% by weight,
Additives: 0.1-0.9 wt .-%, in particular 0.3-0.7 wt .-%, and
Wood fibers: 0.1-5.0 wt .-%, in particular a proportion of 2.0-4.8 wt .-%

A dehumidifying plaster with such a composition has a particularly good moisture-release function and a particularly good moisture-regulating function, a particularly good insulation function, and reliably and permanently prevents cracking even at high temperature fluctuations.

According to a further embodiment of the invention, the dehumidifying plaster mixture as an additional component to sand.

According to a further embodiment of the invention, the proportions of cement or lime, sand, water, additives and wood fibers in a dehumidifying plaster mixture which additionally comprises sand are each the following:
Cement or lime: 15-25% by weight, in particular 22-30% by weight,
Sand: 50-65% by weight, in particular 60-65% by weight,
Water: 5-15% by weight, in particular 8-12% by weight,
Additives: 0.1-0.9 wt .-%, in particular 0.1-0.4 wt .-%, and
Wood fibers: 0.1-5.0 wt .-%, in particular 0.1-3.0 wt .-%.

A dehumidifying plaster with such a composition has a particularly good moisture-release function, a particularly good insulating function, and reliably and permanently prevents cracking even at high temperature fluctuations.

According to a further embodiment of the invention, the wood fibers in the dehumidifying plaster mixture are at least approximately evenly distributed. This is achieved by appropriate mixing of the components in the preparation of the dehumidifying plaster.

According to another embodiment of the invention, a majority of the wood fibers have a diameter of 0.4 to 0.7 mm.

According to a further advantageous embodiment of the invention, a majority of the wood fibers has a length of 0.1 to 3.0 cm.

According to a further embodiment of the invention, the wood fibers comprise 90-98% by weight, in particular 95-97% by weight, of untreated wood fibers, in particular wood fibers of spruce wood, and 2-10% by weight, in particular 3-5% by weight. % Polyurethane material, especially PMDI on. The polyurethane material, in particular PMDI, may in particular be a glue with which the wood fibers are treated, in particular glued, ie coated or wetted, or soaked.

According to a further embodiment of the invention, the wood fibers are untreated wood fibers, in particular untreated wood fibers made of spruce wood.

According to an alternative embodiment, the wood fibers may be treated with flame retardant and / or with water repellents. This flame retardant and / or Water repellents can almost completely enclose the wood fibers.

Flame retardant may be a mixture of ammonium salts strong acids, eg. For example, the flame retardant INH540 Ecocam.

Each of the above-described wood fiber related embodiments, each individually, provides for optimization of the beneficial properties of the dehumidifying plaster: moisture delivery capability, moisture control capability, insulation performance, and prevention of cracking. By combining these embodiments, these capabilities can be optimized.

According to a further embodiment of the invention, at least a part of the wood fibers is a by-product formed in the production of wood fiber insulation panels, e.g. B. when sawing wood fiber boards. This is particularly inexpensive.

• a) 15 bis 50 Gew.-% an anionischen Na-Salzen von Alkylnaphthalinsulfonsäuren,
• b) 25 bis 75 Gew.-% an Na-Salzen von Alkylphenoläthersulfat und/oder Alkylbenzolsulfonat und
• c) 10 bis 40 Gew.-% an einem Styrolmischpolymer mit einer Säurezahl von 5 bis 15, wie es zur Herstellung von wäßrigen Kunststoffdispersionen geeignet ist, sowie gegebenenfalls
• d) 7 bis 15 Gew.-% einer leimfreien hochkonzentrierten Paraffindispersion und
• e) 7 bis 15 Gew.-% an Natriumsalzen eines Naphthalinsulfonsäure-Formaldehyd-Kondensationsproduktes.

According to a further embodiment of the invention, the additive contains surface-active agents and has the following composition:

• a) 15 to 50% by weight of anionic Na salts of alkylnaphthalenesulfonic acids,
• b) 25 to 75 wt .-% of Na salts of alkylphenol ether sulfate and / or alkylbenzenesulfonate and
• c) 10 to 40 wt .-% of a styrene copolymer having an acid number of 5 to 15, as it is suitable for the preparation of aqueous polymer dispersions, and optionally
• d) 7 to 15 wt .-% of a glue-free highly concentrated paraffin dispersion and
• e) 7 to 15 wt .-% of sodium salts of a naphthalenesulfonic acid-formaldehyde condensation product.

This in the DE 18 14 314 described additive ensures in combination with the wood fibers in the dehumidifying plaster mixture for optimal work results.

An alternative additive that gives equally good results is water, sodium sulfate, potassium carbonate and potassium bicarbonate.

According to a further embodiment of the present invention, 10 to 60% by volume of air inclusions are contained in the dehumidifying plaster mixture. These air pockets are usually in the form of small air bubbles. The greater the rate of air entrapment, the better the moisture delivery capability.

The dehumidifying plaster according to the invention can be present as a plaster in not yet hardened form, as a hardened plaster or as a plasterboard.

The plasterboards, which have been poured from plaster, are usually attached with a binder to the building wall or the building ceiling.

The ingredients may be chosen differently as long as they conform to the compositional ratios given in the dependent claims.

A dehumidifying plaster mixture with a high cement content has a higher hardness and a higher adhesion to the building wall or the building ceiling, but at the same time a lower thermal insulation. On the other hand, a dehumidifying plaster mixture with a lower proportion of cement has a lower degree of hardness and a lower adhesion, but a higher thermal insulation.

At a lower wood fiber content of a dehumidifying plaster mixture results in a high degree of hardness of the dehumidifying plaster mixture, and the other way around results in a lower degree of hardness of the dehumidifying plaster mixture at a higher wood fiber content, so that the dehumidifying plaster is softer.

Furthermore, the proportion of water is reduced in the dehumidifying plaster mixture, the larger the sand or the grain size of the sand.

The additive provides a basic measure of air in the dehumidifying plaster. By adding wood fibers, the volume% of these air pockets can be increased.

The less additive contained in the dehumidifying plaster mixture, the harder the entire dehumidifying plaster. Conversely, the more admixture is contained in the dehumidifying plaster, the softer the dehumidifying plaster.

In addition to the wood fibers wood dust may be present in the dehumidifying plaster mixture to a small extent.

The invention is based on embodiments with reference to the accompanying 1 explained in more detail.

1 shows a schematic view of a building wall 2 with a plaster layer applied to the inside 8th , comprising the following exemplified dehumidifying plaster mixtures according to embodiments of the present invention.

The building wall 2 has an outside 4 , an inside 6 , in the usual way a Rendering 8th has been applied, leaving the inside of the building wall 2 an inner interface 6 between building wall 2 and plaster layer 8th forms. The plaster layer 8th has a plaster surface facing the room 10 ,

Furthermore, in the 1 the dehumidifying direction 12 based on three arrows, the plaster layer 8th out into the middle of the room, shown.

At the building wall 2 it is a building wall of an old building with moisture contained therein and / or with continuously penetrating moisture z. B. from outside incident rain, especially heavy or driving rain, by rising capillary moisture from the Baufundament or the like.

• – 65,10 Gew.-% Zement,
• – 31,25 Gew.-% Wasser,
• – 3,13 Gew.-% Holzfasern, und
• – 0,52 Gew.-% des Zusatzmittels, wie es z. B. im Anspruch 12 definiert ist.

A first exemplary dehumidifying plaster mixture according to the invention comprises:

• - 65.10% by weight of cement,
• 31.25% by weight of water,
• 3.13% by weight of wood fibers, and
• - 0.52 wt .-% of the additive, as z. B. defined in claim 12.

• – 64,10 Gew.-% Zement,
• – 30,77 Gew.-% Wasser,
• – 4,62 Gew.-% Holzfasern, und
• – 0,51 Gew.-% des Zusatzmittels, wie es in Anspruch 12 definiert ist.

A second exemplary dehumidifying plaster mixture according to the invention comprises:

• - 64.10% by weight of cement,
• 30.77% by weight of water,
• - 4.62 wt .-% wood fibers, and
• - 0.51 wt .-% of the additive, as defined in claim 12.

• – 65,62 Gew.-% Zement,
• – 31,50 Gew.-% Wasser,
• – 2,36 Gew.-% Holzfasern, und
• – 0,52 Gew.-% Zusatzmittel, wie es in Anspruch 12 definiert ist.

A third exemplary dehumidifying plaster mixture according to the invention comprises:

• 65.62% by weight of cement,
• 31.50% by weight of water,
• - 2.36 wt .-% wood fibers, and
• - 0.52 wt .-% additive, as defined in claim 12.

For all three dehumidifying plaster mixtures mentioned above, cement can also be substituted by lime.

The second dehumidifying plaster mixture according to the invention with the rather high wood fiber content of 4.62% by weight has a lower degree of hardness than the other two dehumidifying plaster mixtures. The third dehumidifying plaster mixture with the wood fiber content of 2.36 wt .-% has a higher degree of hardness than the other two dehumidifying plaster mixtures. With regard to the degree of hardness, the first dehumidifying plaster mixture is located halfway between the other two dehumidifying plaster mixtures indicated.

• – 57,65 Gew.-% Sand,
• – 25,00 Gew.-% Zement,
• – 17,00 Gew.-% Wasser,
• – 0,1 Gew.-% Holzfasern, und
• – 0,20 Gew.-% des Zusatzmittels, wie es in Anspruch 12 definiert ist.

Another exemplary dehumidifying plaster mixture with the additional component sand has the following mixing ratio:

• - 57.65% by weight of sand,
• 25.00% by weight of cement,
• 17.00% by weight of water,
• - 0.1 wt .-% wood fibers, and
• - 0.20 wt .-% of the additive, as defined in claim 12.

This exemplary dehumidifying plaster mix uses crushed sand, which requires more water.

• – 61,99 Gew.-% Sand,
• – 26,88 Gew.-% Zement,
• – 10,75 Gew.-% Wasser,
• – 0,16 Gew.-% Holzfasern, und
• – 0,22 Gew.-% des Zusatzmittels, wie es in Anspruch 12 definiert ist.

Another exemplary dehumidifying plaster mixture with the additional component sand has the following mixing ratio:

• - 61.99% by weight of sand,
• - 26.88% by weight of cement,
• 10.75% by weight of water,
• - 0.16 wt .-% wood fibers, and
• - 0.22 wt .-% of the additive, as defined in claim 12.

This exemplary dehumidifying plaster mix uses round grain or natural sand, which requires less water.

It can be seen that when sand is added as an additional ingredient, the percentages of cement, water, wood fibers and the admixture are significantly reduced.

For the formation of the wood fibers and the air inclusions, reference is made to the dependent claims and the above description.

LIST OF REFERENCE NUMBERS

2

building wall

4

outside

6

Interior interface between building wall and plaster layer

8th

Rendering

10

Plaster layer surface

12

Entfeuchtungsrichtung

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 2814317 C [0003]
• DE 2814317 [0014]
• DE 1814314 [0034]

Claims (15)

Dehumidifying plaster ( 8th ) for the coating of building walls ( 2 ), in particular building interior walls ( 6 ), and / or building ceilings, comprising a mixture of cement or lime, water, and an additive, characterized in that the mixture additionally comprises wood fibers. Dehumidifying plaster ( 8th ) according to claim 1, wherein cement or lime comprises a proportion of 60-70% by weight, in particular a proportion of 62-67% by weight, water a proportion of 25-35% by weight, in particular a proportion of 29 -32% by weight, the admixture a proportion of 0.1-0.9 wt .-%, in particular a proportion of 0.3-0.7 wt .-%, and the wood fibers account for 0.1- 5.0 wt .-%, in particular a proportion of 2.0-4.8 wt .-% have. Dehumidifying plaster ( 8th ) according to claim 1, wherein the mixture additionally comprises sand. Dehumidifying plaster ( 8th ) according to claim 3, wherein cement or lime comprises a proportion of 15-25% by weight, in particular a proportion of 22-30% by weight, sand a proportion of 50-65% by weight, in particular a proportion of 60 -65% by weight, water a proportion of 5-15% by weight, in particular a proportion of 8-12% by weight, the additive a proportion of 0.1-0.9% by weight, in particular one Proportion of 0.1-0.4 wt .-%, and the wood fibers have a proportion of 0.1-5.0 wt .-%, in particular a proportion of 0.1-3.0 wt .-% have. Dehumidifying plaster ( 8th ) according to any one of the preceding claims, wherein the wood fibers are evenly distributed in the mixture. Dehumidifying plaster ( 8th ) according to one of the preceding claims, wherein a majority of the wood fibers has a diameter of 0.4 to 0.7 mm. Dehumidifying plaster ( 8th ) according to one of the preceding claims, wherein a majority of the wood fibers has a length of 0.1 to 3.0 cm. Dehumidifying plaster ( 8th ) according to one of the preceding claims, wherein the wood fibers 90-98 wt .-%, in particular 95-97% wt .-% untreated wood fibers, in particular of wood fibers from spruce wood, and 2-10 wt .-%, in particular 3-5 wt .-% polyurethane material, in particular PMDI have. Dehumidifying plaster ( 8th ) according to any one of claims 1 to 7, wherein the wood fibers are untreated wood fibers, in particular untreated wood fibers of spruce wood. Dehumidifying plaster ( 8th ) according to any one of claims 1 to 7, wherein the wood fibers are wood fibers treated with flame retardant and / or water repellents. Dehumidifying plaster ( 8th ) according to claim 10, wherein the flame retardant and / or the hydrophobing agent almost completely encloses the wood fibers. Dehumidifying plaster ( 8th ) according to one of the preceding claims, wherein the additive comprises surface-active agents, and wherein the additive a) 15 to 50 wt .-% of anionic Na salts of Alkylnaphthalinsulfonsäuren, b) 25 to 75 wt .-% of Na salts of alkylphenol ether sulfate and / or alkylbenzenesulfonate and c) 10 to 40 wt .-% of a styrene copolymer having an acid number of 5 to 15, as it is suitable for the production of aqueous polymer dispersions, and optionally d) 7 to 15 wt .-% of a glue-free highly concentrated paraffin dispersion and e) 7 to 15 wt .-% of sodium salts of a naphthalenesulfonic acid-formaldehyde condensation product. Dehumidifying plaster ( 8th ) according to any one of claims 1 to 11, wherein the additive comprises water, sodium sulfate, potassium carbonate and potassium bicarbonate. Dehumidifying plaster ( 8th ) according to one of the preceding claims, wherein in the mixture 10-60 vol .-% air inclusions are included. Dehumidifying plaster ( 8th ) according to one of the preceding claims, present as a plaster in not yet hardened form, as a hardened plaster or as a plasterboard.

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