JPH0133224B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for preventing dew condensation from forming on walls, ceilings, and other required surfaces of buildings, particularly inside the building.

It has been well known that dew condensation occurs on walls and ceilings inside buildings such as houses and offices.

This is because the inside of a building contains a lot of moisture (water vapor) in the air due to the human living environment, and this moist air is cooled by the interference of the outdoor temperature and maintains a temperature lower than the indoor temperature. When it comes into contact with a wall, moisture in the air condenses into small water droplets that wet the wall.

Since this condensation has an extremely negative impact on human life and the preservation of buildings, various solutions have been devised, but none have been definitive. External insulation structures for walls have been proposed to prevent condensation from condensation, but external insulation structures for walls are complicated to construct, time consuming, and lead to soaring costs, making them difficult to popularize. This is the current situation.

Therefore, as a result of intensive research and development aimed at solving dew condensation in buildings, the present inventor focused on the unique properties of water-absorbing polymers, and found that it is possible to suppress the occurrence of dew condensation as much as possible. It is something that has become familiar.

Now, in the present invention, a super absorbent polymer plays the most important role.
absorbs several hundred times its own amount of water in water, swells, and forms a hydrogel. Structurally, it is a water-soluble polymer that has been slightly crosslinked to make it insolubilized.

Types of water-absorbing polymers include polyacrylonitrile derivatives, polyacrylamides and polyacrylates, saponified vinyl acetate/methyl acrylate copolymers, and polyoxyethylene, all of which have hydrophilic groups in polyoxyethylene. It is a polymeric organic material with chains or carboxylic acid side chains. In addition, there are crosslinked polymers of nonionic polymers such as polyvinylpyrrolidone and polyvinyl alcohol, and sulfonic acid polymers such as polystyrene sulfonic acid and poly-2-acrylamido-2-methylpropanesulfonic acid. These are polymers with hydrophilic functional groups.

The method of the present invention aims to suppress the occurrence of dew condensation as much as possible by effectively utilizing the extremely high water absorption capacity of the above-mentioned water-absorbing polymer. A moisture-absorbing layer made of a foam formed into a cell structure containing one or more of the above-mentioned water-absorbing polymers and a membrane or thin-plate moisture-permeable decorative layer are attached to a required surface such as a surface. It is characterized by the fact that it can be pasted with other objects.

The moisture absorbing layer, which is one of the main parts constituting the present invention, is made of a foam with a cell structure, preferably an open cell structure, and its materials include polyethylene, polyvinyl chloride, polyurethane, phenolic resin, urea. Examples include resin, vinylon, and synthetic rubber. Also, from the point of view of flexibility,
Among them, polyethylene, polyvinyl chloride, polyurethane, vinylon, synthetic rubber (NBR, CR,
EPT, Si, SBR, U) etc. are good. It may be made by molding these plastic foam materials containing 40 to 50% water-absorbing polymer.

The moisture-permeable decorative layer, which is another essential component, is in the form of a film, sheet, felt, etc., or a thin plate, and is made of synthetic resin, paper,
It can be made of cloth, wood, metal plywood, synthetic board, etc., but the condition is that it has a large number of ventilation holes. For example, in the case of cloth, breathability is ensured, but
In the case of synthetic resin, paper, wood, metal, plywood, and synthetic board, a large number of ventilation holes must be formed during the molding process or post-processing.

Moreover, the surface of the film or thin plate made of any of these materials needs to be appropriately colored or provided with an appropriate design of irregularities or patterns to give it cosmetic properties.

The moisture-absorbing layer and the moisture-permeable decorative layer are then bonded together in a manner that does not impede the movement of moisture, and then supplied to the construction site. If these two layers are bonded by spot bonding or net bonding, moisture movement will not be hindered. The desired prevention of dew condensation can be achieved by attaching the above composite layer to the required surface on which dew condensation is to be prevented.

Therefore, according to the basic structure of the present invention, the moisture absorbing layer and the moisture permeable decorative layer provided on the required surface are interposed between the hydrated air and the required surface, so that the hydrated air directly contacts the required surface. At the same time, the moisture-absorbing layer acts as a conductive barrier to prevent the temperature from dropping on the surface of the required surface, thereby greatly suppressing the occurrence of condensation due to temperature drops in the moisture-containing air that exists near the moisture-permeable makeup layer. be done.

Moreover, even if moisture in the air condenses and forms dew near the moisture-permeable makeup layer, the moisture that passes through the moisture-permeable makeup layer is absorbed by the highly water-absorbing polymer contained in the moisture-absorbing layer. However, there will be no condensation.

Furthermore, if the moisture absorbing layer absorbs moisture in the air, it will swell in the direction of its overall thickness. At this time, since the layer absorbs water, as the thickness increases, the heat shielding effect increases, and the effect of suppressing the formation of condensation increases.

The moisture-absorbing layer that has absorbed moisture from the air temporarily retains the moisture inside, but if the moisture in the surrounding atmosphere, that is, the air, decreases relatively, the moisture-absorbing layer gradually removes moisture in the form of dilute water vapor. It is released and prepared for the next water absorption chance.

In this way, the moisture-absorbing layer provided on the required surfaces of a building performs a type of breathing action by absorbing moisture in the air and exhausting it, which is similar to the breathing action of the earthen wall structure of traditional Japanese houses. Although there are physical and chemical differences, they essentially have the same effect.

Hereinafter, the method of the present invention will be described in detail based on examples to facilitate understanding.

For example, 40 to 50% of the total weight of a polyacrylonitrile derivative water-absorbing polymer is added to a one-component polyurethane rigid foam preparation liquid, which is a material for forming polyurethane foam, and the mixture is sealed and housed in a sealed pressure can.

Then, during molding, if extrusion molding is performed to obtain a predetermined thickness while pouring from a sealed pressure can, the one-component polyurethane rigid foam preparation containing a water-absorbing polymer will harden while foaming due to moisture in the air. , forming a moisture absorption layer.

A moisture-absorbing layer formed from a one-component polyurethane rigid foam preparation containing 45% water-absorbing polymer was tested in accordance with the dew-proof test specified in JASS23M-102, lightweight aggregate spray material (draft). Where I went,
It was 0.48 g/cm ² (average value of 5 measurements). By the way, in the case of cement mortar, it is 0.07~0.1g/ ^cm2 ,
In the case of a lightweight aggregate spray material made of vinyl acetate emulsion using vermiculite, it is 0.25 to 0.3 g/cm ² .

As an example of a moisture-permeable makeup layer, if a breathable, coarsely woven cloth is attached with an organic solvent-based adhesive to a moisture-absorbing layer made of a urethane foam layer containing a water-absorbing polymer, condensation with makeup will occur. A layer for preventing dew condensation is obtained, and if this layer is applied to a surface of a building where dew condensation prevention is required, the interior becomes decorative and dew condensation is prevented.

The moisture absorbing layer using this fabric as a moisture permeable decorative layer and its composite layer were tested in accordance with the dew proof test specified in JASS23M-102, lightweight aggregate spray material (draft), and the result was 0.51 g/cm. ² (average value of 5 measurements).

In the case of this method, it is thought that the cloth used as the makeup layer also absorbed moisture.

As described above, the method of the present invention can prevent dew condensation from forming on required surfaces of a building, such as walls, using extremely simple technical means, and therefore protects furniture and furnishings from moisture and protects the building itself. It has many features such as an extended service life, and when the indoor air dries, the moisture-absorbing layer releases moisture back into the room and adjusts the humidity, creating an extremely comfortable living environment. It is.

Claims (1)

[Claims] 1. A moisture-absorbing layer made of a foam with an open cell structure containing a water-absorbing polymer and a moisture-permeable decorative layer in the form of a membrane or thin plate attached to the required surfaces of buildings to prevent condensation. A method for preventing condensation on buildings, which is characterized by pasting the condensation on buildings.