WO1999061544A1 - Method for the controlled humidification of ambient air - Google Patents

Abstract

The invention relates to a method for the controlled humidification of ambient air or of a supply of ambient air. According to said method, an aqueous shaped body is exposed to the ambient air or supply of ambient air to be humidified. A dimensionally stable composition containing alkaline metal carboxylates of carboxylic acids with approximately 8 to 26 C-atoms, and water is used for said aqueous shaped body.

Description

 Process for controlled humidification of indoor air

The invention relates to a method for the controlled humidification of room air using water-containing, dimensionally stable compositions which contain alkali metal carboxylates, water and optionally further additives.

External factors such as light, temperature and humidity usually play a major role in the well-being of people who are in rooms. Especially in air-conditioned, d. H. heated or cooled rooms, the use of heating or cooling systems usually leads to a sharp drop in the moisture content of the room air. This effect is usually supported in rooms or buildings that have air conditioning by the fact that the windows cannot be opened and therefore the room or the building cannot be supplied with fresh air directly. Similar problems often arise in heated living rooms, where dry heating air circulates in the room, especially in winter, and is usually not ventilated enough to save energy or be sensitive to cold. In such cases, the mostly dry winter air is further reduced in the moisture content by heating the rooms. People who are in such rooms with a low level of moisture in the air often complain of complaints such as burning eyes, dry, exciting and often even irritated skin, as well as respiratory complaints, which result in complaints of the lower as well as the upper respiratory tract, for example pain in the bronchi, sore throat or an increased susceptibility to the cold.

In order to prevent such phenomena, two concepts have so far been pursued, but they often have serious disadvantages. For example, open, water-filled containers were installed on radiators and heating systems for room humidification, which then released their water to the environment in a more or less controlled manner. However, the handling of such containers, in particular the filling with water, generally leads to frequent spilling of the water when installing the container or when filling it. However, this often results in rust damage to the heating system or damage to the surface. The latter point is particularly disadvantageous in rooms which have sensitive or valuable flooring, for example a parquet floor.

Another frequently practiced way of humidifying the air is to set up an electrical device that releases water vapor. However, such devices are known to tend to be contaminated by algae, bacteria and fungal growth. Here, for example, there is a risk that microorganisms, which may cause diseases, are entrained in the water aerosol particles released into the room air. Furthermore, such devices often require a relatively large amount of space, i. that is, they often disturb the aesthetic image of the room or work with unpleasant noise. Furthermore, there is also the risk of spilling water when filling or inadvertently knocking over the device, even with devices which work with "liquid" water. In addition, electrical energy is constantly required.

Both methods of room humidification also have the disadvantage that due to constant evaporation of water there is a calcification of the water tank, which can lead to the container being unusable over a more or less long period of time or at least requires regular decalcification by the user. In contrast, the task was to provide a method for the controlled humidification of room air, which does not have the disadvantages mentioned above.

It has now been found that water-containing moldings which, from a dimensionally stable composition containing alkali metal carboxylates of carboxylic acid having 8 to 26 carbon atoms and water, enable controlled humidification of room air without the disadvantages mentioned above occurring.

The invention therefore relates to a process for the controlled humidification of room air or a room air supply, in which a water-containing molded article is exposed to the room air or room air supply to be humidified, the water-containing molded article having a dimensionally stable composition containing 1 to 40% by weight of alkali metal carboxylates of carboxylic acids 8 to 26 carbon atoms and 60 to 99 wt .-% water is used.

The dimensionally stable composition used as a water-containing molded body thus has a high water content, this water being controlled and being released with respect to the rate at which water is released, which is adjustable within certain limits.

As the main structural component, the dimensionally stable composition contains about 1 to 40% by weight of alkali metal carboxylates of carboxylic acids with about 8 to 26 carbon atoms. Such fatty acids can be obtained, for example, from fatty substances such as are present in nature in particular as vegetable and animal oils and fats. Such "soaps" generally also have an antimicrobial effect, which means that microbes such as fungi, bacteria or algae do not or only weakly affect the surface of the shaped body. Vegetable and animal oils and fats are present in nature in the form of natural mixtures of different fatty acid glycerol esters, for example in the form of palm oil, palm kernel oil, palm stearin, olive oil, rapeseed oil, korean oil, sunflower oil, cotton oil, peanut oil, linseed oil, lard oil, fish oil, fish oil or pork lard.

The naturally occurring fatty substances generally do not provide identical fatty acids, but rather mixtures of fatty acids with different chain lengths, branches, functional groups or unsaturated molecule sections. One usually speaks of fatty acid cuts. The dimensionally stable composition of the present invention can be based both on alkali metal salts of pure fatty acids (fatty acids with identical molecular structure) and on alkali metal salts of fatty acid cuts. As a rule, good results can be achieved with both variants, but in a preferred embodiment alkali metal salts of carboxylic acids from fatty acid cuts are used, in particular from fatty acid cuts which have a predominant proportion of fatty acids with about 12 to about 22 carbon atoms.

Examples of generally suitable carboxylic acids with about 8 to 26 carbon atoms, preferably about 12 to 22 carbon atoms, are: Capron, Caφyl, Caprin, Laurin, Myristin, Palmitin, Stearin, Arachin, Behen-, Cerotinic, pentadecanoic, margaric, tridecanoic and lignoceric acids. Examples of unsaturated fatty acids with about 8 to 26 carbon atoms, preferably about 12 to 22 carbon atoms, are: myristolein, palmitolein, oil, elaidin, petroselin, eruca, linole, linoleic, arachidone, clupanodone , Docosahexaenic, eicosapentaenic and gadoleic acid.

Due to their high natural content of saturated fatty acids, alkali metal salts of carboxylic acids from fatty acid cuts based on coconut oil, palm kernel oil or beef tallow are used in a preferred embodiment of the present invention. In principle, carboxylic acid salts of the alkali metals Li, Na, K, Rb, Cs can be used alone or as a mixture of two or more thereof in the context of the present invention. However, carboxylic acid salts of the alkali metals Li, Na, K, in particular the Na carboxylates, are preferably used.

The dimensionally stable compositions according to the invention preferably have the alkali metal carboxylates of the type described above in an amount of about 2 to about 10% by weight, in particular in an amount of about 3 to about 8% by weight. Preferred carboxylic acids are myristic, palmitic and stearic acids, which can be used directly as corresponding salts or, for example, after neutralization with NaOH.

In a preferred embodiment of the invention, the dimensionally stable composition therefore contains about 2 to about 10% by weight of Na-C ^. ^ - carboxylate and about 70 to about 98% by weight of water.

The dimensionally stable composition to be used in the process according to the invention can, in addition to the above-mentioned alkali metal carboxylates and water, also 0 to about 20% by weight of an additive selected from the group consisting of solvents, regulators, fragrances, insecticides, preservatives, thickeners or moisture indicators, or a mixture of two or more of them.

Suitable solvents are, for example, all water-soluble solvents, e.g. short-chain alcohols with about 2 to about 8 carbon atoms.

In a preferred embodiment, the composition is formulated largely without solvent. However, small amounts can be introduced, for example, using additives (eg perfume oils). Furthermore, the dimensionally stable composition to be used according to the invention can contain regulators. In the context of the present invention, a regulator is understood to mean a connection with which the vapor pressure of the water contained in the dimensionally stable composition can be set within certain limits. Suitable regulators include, for example, non-hygroscopic salts such as NaCl or hygroscopic salts such as CaCl ₂ or Na ₂ SO ₄ and swellable substances, for example clays, silica gels, molecular sieves or polyalcohols. The controllers mentioned can each be used alone or as a mixture of two or more of them. The controllers can be either finely dispersed or coarsely dispersed (eg granulated) in the humidifier.

Suitable polyalcohols include, for example, alcohols with two or more OH groups and up to about 30 carbon atoms, for example 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2, 3-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 1, 8-octanediol, diethylene glycol, neopentyl glycol, 1, 4-

Bishydroxymethylcyclohexane, 2-methyl-1, 3-propanediol, 1, 2,6-hexanetriol, glycerol, diglycerol, polyglycerol, trimethylolpropane, trimethylolethane, pentaerythritol, sorbitol, methylglycoside, dimerdiol, trimertriol, glucose, alkylpolyglycosaccharides as well as di- and polysiloxides. The alcohols mentioned can also be present in the dimensionally stable composition as EO or PO addition products with or without a sulfonic acid group. Lactams such as ε-caprolactam can also serve as regulators.

The presence of regulators means that the amount of water dispensed per unit of time can be limited within certain limits depending on the external conditions and requirements.

Furthermore, the dimensionally stable composition can contain fragrances. Fragrances are understood to mean those fragrances that are found in humans Generate a pleasant sense of smell or trigger an improvement in general well-being. In the context of the present invention, the term “fragrances” also encompasses essences and aromas, for example healing fragrances or substances which promote healing, such as the essential oils.

Particularly suitable fragrances are e.g. in the reference work by E. Ohloff, Riechstoffe und Geruchsinn (ISBN 3-540-5256-2, Springer Verlag) from 1990. Vegetable fragrances, petrochemical or animal fragrances are suitable, for example. Depending on the destination of the humidifier (e.g. bathroom or bedroom), fragrances such as orange peel oil, sandalwood oil or incense can be used.

The dimensionally stable composition that can be used according to the invention can furthermore have insecticides or repellents. The insecticides ensure that flies, brakes, mosquitoes, cockroaches, bugs or fleas, for example, are effectively combated, which, for example, have a harmful effect on people as transmitters of diseases. Insecticides may also be present, the effect of which is primarily directed at plant pests. This is particularly recommended if the dimensionally stable composition is used, for example, to maintain a certain level of humidity in rooms that are used for growing useful or ornamental plants.

As insecticides or repellants in the context of the present invention are, for example, some of the fragrances cited in the above reference work (e.g. clove oil, cinnamon oil, mustard oil), dimethyl phthalate, benzoic acid diethylamide, phenylcyclohexanone, ethylhexanedial, chlorinated hydrocarbons (e.g. DOT), phosphorus compounds, carbamates, nicotine or mineral oils . Depending on the location of the humidifier, such insecticides or repellents should be selected that are toxicologically harmless as possible. Furthermore, the dimensionally stable compositions can contain thickeners which, for example, can contribute to the dimensional stability of the composition. In principle, organic, high-molecular substances that absorb water while swelling are suitable as thickeners. Examples of suitable organic, natural thickeners are agar-agar, carrageenan, tragacanth, gum arabic, alginates, pectins, polyoses, guar gum, locust bean gum, starch, dextrins, gelatin, casein and the like. Organic, modified natural substances, for example carboxymethyl cellulose and homologous cellulose ethers, hydroxyethyl and propyl cellulose, core meal ether, starch derivatives and the like can also be used.

The organic, fully synthetic thickeners include, for example, polyacrylic and polymethacrylic compounds, vinyl polymers, polycarboxylic acids, polyethers, polyamides and polyurethanes. If appropriate, the use of inorganic thickeners is also possible, these include, for example, polysilicic acids, clay minerals such as montmorillonite, zeolites or silicas. The said thickeners can also serve as regulators by influencing the rate of evaporation of the water.

Dyes or pigments or mixtures thereof can also be added to the dimensionally stable compositions, which generally have a decorative character, but can also perform a warning or informative function. The dyes or pigments, or their mixtures, can be homogeneously distributed as color-imparting components in the dimensionally stable composition. However, it is also possible to apply the coloring components only superficially to the dimensionally stable composition. The dimensionally stable compositions can thus be used, for example, as a decorative room element or as an advertising medium. Suitable dyes or pigments are, for example, all water-soluble or dispersible substances which are largely harmless from a toxicological point of view.

Furthermore, the dimensionally stable compositions can contain moisture or freshness indicators which make the residual moisture content of the dimensionally stable composition optically recognizable or indicate whether the packaging was opened before the intended use. Such indicators can, for example, be used in conjunction with a suitable optical measuring system to determine the moisture content of the dimensionally stable composition, even if they are installed in inaccessible places, for example in a ventilation system or in an air conditioning system, without time-consuming and uncomfortable activities, for example opening a Need to perform ventilation system.

Suitable moisture and freshness indicators are e.g. Indicator dyes such as phenolphthalein or thymoiphthalein or salts that change color due to changes in water of crystallization (e.g. co-salts).

The dimensionally stable compositions can be produced in various ways. For example, the alkali metal soaps of the above carboxylic acids can be dissolved in water at temperatures above about 50 ° C. On cooling, the dimensionally stable compositions to be used according to the invention are then formed. However, it is also possible to heat fatty acids or fats and to carry out the saponification by adding a suitable alkali metal salt, for example an alkali metal hydroxide. If such a mixture is then allowed to cool, the dimensionally stable compositions also result. An advantage of the present invention is that the dimensionally stable compositions are suitable for almost any shape due to the simple method of preparation. For example, blocks, balls, cubes, rods, discs, figures and the like are possible. The evaporation rate of the water can also be controlled in a targeted manner via the surface of the moldings. The solid soap structure is advantageous here, ie the moldings do not flow together over time. It is also possible, for example for use in ventilation devices, to pour the dimensionally stable compositions in the liquid state into certain holders which, after the composition has solidified, enable simple use in corresponding devices. After the water and other volatile constituents have evaporated from the dimensionally stable composition, only a mixture of alkali metal carboxylates and possibly non-volatile additives remains. Such a residue can subsequently be used, for example, as a hand or body cleanser. However, it is also possible to use the rest again by appropriate work-up to produce a dimensionally stable composition.

In a preferred embodiment of the invention, the dimensionally stable composition is therefore laid out on a suitable base in a room filled with room air to be humidified or is exposed to an air flow to be humidified in a suitable holder or packaging. In a further particular embodiment of the invention, the air stream to be humidified of the room air supply is heated or cooled before, during or after the humidification.

Another object of the invention is the use of a dimensionally stable composition containing 1 to 40 wt .-% alkali metal carboxylates of carboxylic acids with 8 to 26 carbon atoms and 60 to 99 wt .-% water, in particular a dimensionally stable composition containing 2 to 10 wt .-% % Na-C ₁₂ . ₂₂ - Carboxylate and 70 to 98 wt .-% water, for humidifying room air or a room air supply.

In a preferred embodiment of the use according to the invention, the dimensionally stable composition contains 0 to 20% by weight of an additive selected from the group consisting of solvents, regulators, fragrances, insecticides, thickeners, dyes, pigments and moisture indicators, or a mixture of two or more thereof .

In the context of the use according to the invention, the dimensionally stable composition is preferably laid out on a suitable base in a room filled with room air to be humidified or exposed to an air flow to be humidified in a suitable holder or packaging.

The following examples are intended to illustrate the invention in more detail.

Examples:

Example 1 Example 2 Example 3

Na myristate 4% 1% 3%

Na palmitate 2% / 0.99%

Na stearate / 4% 3%

Odorant 0.01% / /

(Perfume oil)

Glycerin 9.99% 5% / ε-caprolactam 1% / /

Phenolphthalein / / 0.01%

Water 83% 90% 93% adjusted pH 8 9 10.9 All components are taken up in water at 70 ° C and homogenized (at the same temperature). Small amounts of NaOH adjust the pH (if necessary) in the range 7 to 11. The liquid, low-viscosity masses can be poured into any shape and solidify below 50 ° C. Molded bodies can later be produced from blocks.

Properties of the molded body according to Examples 1 to 3

The shaped bodies according to Examples 1 and 2 are whitish masses, while Example 3, on the other hand, gives blue-purple colored shaped bodies. If airtight and watertightly packaged molded articles according to Example 3 are removed from the packaging, the surface discolors after a few minutes (change in pH value due to CO ₂ absorption). The consumer sees that the system was unopened and is now starting to work.

Depending on the positioning in the room, temperature, existing air humidity, the amount and geometry of the moldings, room size and air exchange, the examples emit moisture and odor (example 1) to the environment for a few days to several weeks. Example 1 lasts about 20 to 30% longer compared to Examples 2 and 3 and forms an opaque soap after drying, which e.g. can be used for hand washing. The residues from Examples 2 and 3 are white and can be used for the same purpose. The shaped bodies are neither dirty nor covered with germs after drying.

Claims

claims 1. A process for the controlled humidification of room air or a room air supply, in which a water-containing molded body is exposed to the room air or room air supply to be humidified, characterized in that as a water-containing molded body a dimensionally stable composition containing 1 to 40% by weight alkali metal carboxylates of carboxylic acids with 8 up to 26 carbon atoms and 60 to 99 wt .-% water is used. 2. The method according to claim 1, characterized in that the dimensionally stable composition 0 to 20 wt .-% of an additive selected from the group consisting of solvents, regulators, fragrances, insecticides, thickeners, dyes, pigments and moisture indicators, or a mixture of two or more of them. 3. The method according to any one of claims 1 or 2, characterized in that the dimensionally stable composition 2 to 10 wt .-% Na-C _12th Contains ₂₂ carboxylate and 70 to 98 wt .-% water. 4. The method according to any one of claims 1 to 3, characterized in that the dimensionally stable composition is laid out on a suitable base in a room filled with room air to be humidified or in a suitable holder or packaging is exposed to an air flow to be humidified of a room air supply. 5. The method according to claim 4, characterized in that the air flow to be humidified of the room air supply is heated or cooled before, during or after the humidification. 6. Use of a dimensionally stable composition containing 1 to 40 wt .-% alkali metal carboxylates of carboxylic acids with 8 to 26 carbon atoms and 60 to 99 wt .-% water for humidifying room air or a room air supply. 7. Use according to claim 6, characterized in that the dimensionally stable composition 0 to 20 wt .-% of an additive selected from the group consisting of solvents, regulators, fragrances, insecticides, thickeners, dyes, pigments and moisture indicators, or a mixture of two or more of them. 8. Use according to claim 6 or 7, characterized in that the dimensionally stable composition is laid out on a suitable base in a room filled with room air to be humidified or in a suitable holder or packaging an air stream to be humidified is exposed to a room air supply.