JP2536770Y2 - Wall covering - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a wall covering capable of preventing dew condensation.

2. Description of the Related Art Conventionally, in a building or the like, when a temperature difference and a humidity difference between outside air and a room are large, dew condensation easily occurs on a surface of a wall material in a room or inside a wall. If condensation forms on the surface of the wall material, the mold tends to be unsanitary and unattractive, and if dew forms inside the wall material, the wall is liable to rot and condensed in cold regions There is a problem that the cell tissue on the wall is destroyed by freezing of water.

Therefore, conventionally, in order to prevent condensation, using a moisture-permeable membrane or sheet, to release moisture to the outdoors,
Absorption of water has been performed using a water-absorbing polymer.

However, in the former case, since the moisture itself can pass, even if dew condensation on the surface of the wall material can be suppressed, the moisture that has passed through the wall material does not reach the inside of the wall and the wall material laminated surface of the wall. It causes dew condensation on the opposite side, that is, so-called internal dew condensation, and cannot solve the above problems.

Also, as an example of the latter case, JP-A-62-231740 discloses a method in which a mixture of a water-absorbing polymer, a foaming agent, a polyolefin resin, and a vinyl chloride resin is applied to a substrate, and then heated and foamed. A moisture-wicking vinyl wall covering with continuous vents is disclosed. However, in the wall covering obtained by this method, since the water-absorbing polymer is surrounded by the vinyl chloride resin, the water-absorbing polymer cannot sufficiently exhibit the water absorbing performance, and dew condensation on the surface of the wall covering material. Was produced. Further, since the water-absorbing polymer mainly absorbs water in the state of water, in a place with high humidity, the water-absorbing polymer tends to absorb water and condensate easily on the surface of the wall material due to the relationship between the water-absorbing speed and the condensation speed. In general, since the superabsorbent polymer is cross-linked, once it absorbs water, it is difficult to release moisture, so that water is accumulated one after another, but it is impossible to accumulate moisture indefinitely. For this reason, it is impossible to prevent dew condensation, and the wallpaper swollen by absorbing water has poor dimensional stability, and it has been difficult to use the wallpaper for a long time.

Furthermore, since a hole is formed when the gun is fired, moisture can freely pass through the wall covering, so that dew condensation may occur inside the wall and on the side opposite to the wall covering surface of the wall.

As described above, although a wall covering material using a membrane or a sheet or a water-absorbing polymer that is moisture permeable but does not allow moisture to pass has been proposed, none of them sufficiently exerts the effect of preventing dew condensation. Therefore, the appearance of a wall covering material having an excellent dew condensation preventing effect has been awaited.

[Problem to be Solved by the Invention] An object of the invention is to provide a wall covering material excellent in dew condensation prevention.

[Means for Solving the Problems] The wall covering material of the present invention is a breathing material (2) composed of a mixture of a highly moisture-absorbing and releasing material in which metal ions are contained in a colloidal state in a water-soluble polymer and a poorly water-soluble polymer. ) Has a moisture-proof sheet (1) laminated on one side.

The above water-insoluble polymer and / or moisture-proof sheet (1)
If is a vinyl chloride resin, more excellent respirability, moisture proofness, and economic efficiency are exhibited.

In addition, if the surface material (4) having moisture permeability is laminated on the breathing material side of the wall covering material, the performance of the breathing material (2) is not hindered, and the wall covering material has an excellent appearance.

[Operation] The wall covering material of the present invention exhibits excellent dew condensation prevention performance by laminating the moisture-proof sheet (1) on one side of the breathing material (2). In other words, although the breathing material (2) can absorb and release moisture, it is not possible to control the direction in which the breathing material is released, but the moisture-proof sheet (1) is laminated on one side of the breathing material (2). As a result, it is not possible to release moisture to the moisture-proof sheet side, so that the flow of moisture (5) is limited from room to room, and no surface condensation occurs,
Moisture does not pass through the wall covering and penetrate the walls, so there is no internal condensation. That is, neither internal condensation nor surface condensation occurs.

In addition, the moisture-proof sheet (1) not only functions as described above to prevent the passage of moisture but also functions as a heat insulating layer for reducing the temperature difference between the inside and the outside, so that dew condensation hardly occurs.

Since the respiratory member (2) of the present invention is composed of a mixture of a highly moisture-absorbing and releasing material in which metal ions are contained in a colloidal state in a water-soluble polymer and a water-resistant polymer, excess moisture absorbs moisture,
After the amount of moisture absorption becomes saturated, the occurrence of dew condensation can be suppressed by releasing moisture. Such a breathing material (2) exhibits excellent moisture absorption / release properties due to the action of the high moisture absorption / desorption material, and is fixed by the poorly water-soluble polymer, so that it has form stability.

Since the respiratory material (2) of the present invention is composed of a highly moisture-absorbing and desorbing material and a poorly water-soluble polymer, it is thought that moisture absorption and desorption is inhibited by the poorly water-soluble polymer. Not an excellent material. This moisture absorption / desorption property does not decrease because the poorly water-soluble polymer is an aqueous emulsion and the highly moisture-absorbing / desorbing material is in a colloidal state.
Even if the mixture of the types is uniformly dispersed and dried, even if it is dried, since it is in an agglomerated state with micropores when viewed microscopically, it is possible that moisture can be absorbed and released by the highly hygroscopic material through these micropores. Conceivable.

When a highly moisture-absorbing and dewatering polymer and a water-based poorly water-soluble polymer are mixed and used for a wall covering as in the prior art, in addition to absorbing water mainly in a water state, the surface tension of the water is reduced. Therefore, the water does not easily pass through the micropores, and the moisture absorption performance is remarkably low. On the other hand, the respiratory material (2) of the present invention can absorb and release moisture in the state of water vapor before it becomes water, and thus has excellent moisture absorption and release. It exerts its power.

Such a highly hygroscopic material used in the present invention is a material in which metal ions are contained in a colloidal state in a water-soluble polymer.

The water-soluble polymer in the highly moisture-absorbing and releasing material includes all water-soluble polymers such as natural polymers, semi-synthetic polymers, and synthetic polymers.

The colloid state means a state in which metal ions are dispersed in a water-soluble polymer when a highly hygroscopic material is dissolved in water. In this state, the absorption wavelength obtained from the absorbance analysis performed by dissolving the highly hygroscopic material in water and the absorption wavelength obtained from the absorbance analysis obtained when the metal salt is simply dissolved in water almost match. You can check. When the highly hygroscopic material is dissolved in water, the highly hygroscopic material swells with excessive moisture and is a viscous liquid such as a sol. Different states.

When the metal ion and the water-soluble polymer form a chelate, that is, when they are coordinated, they should exhibit an absorption wavelength different from the absorption wavelength obtained by simply dissolving the metal salt in water. However, when the highly moisture-absorbing and desorbing material of the present invention is dissolved in water, it exhibits the same absorption wavelength as when the metal salt is simply dissolved in water. In the same state as the colloidal state of the ion, it is considered that no chelate was formed.

Since the highly moisture-absorbing and desorbing material used in the present invention is stable and does not change before and after drying even during the drying process, the absorbance analysis may be performed before drying during the manufacturing process, or the highly moisture absorbing and desorbing material may be used. May be dissolved in water again. It should be noted that the degree of dissolution of the highly hygroscopic material in water is such that absorbance analysis is possible, and differs depending on the metal salt, water-soluble polymer, and the like used.

Since the highly moisture-absorbing and desorbing material of the present invention uses a water-soluble polymer, water tends to collect on the polar portion of the water-soluble polymer. That is, hydrogen atoms having low electron density of water molecules are easily electrostatically attracted to a portion having high electron density. After the water molecules are sucked, the hydration power of the metal ions dispersed in the highly hygroscopic material is higher than the electrostatic force, so the collected water moves to the metal ions, This metal ion is also electrostatically held in the polar part inside the water-soluble polymer.

Conversely, if the humidity of the outside air drops or dries,
The vapor pressure of the outside air decreases, and the force due to the difference in vapor pressure is stronger than the hydration power of metal ions, and the highly moisture-absorbing and desorbing material of the present invention releases moisture absorbed. In other words, the water hydrated by the metal ions moves to the polar part of the water-soluble polymer, contrary to the case of absorbing moisture, and then is released to the atmosphere.

When the moisture absorption / desorption material used in the present invention reaches a saturated state, the moisture absorption / desorption is repeated in that state. this is,
Since the interaction of the water molecule with the metal ion after reaching the saturation state is weak, moisture release easily occurs.

In other words, the high moisture absorption / release material of the present invention absorbs excess moisture, and when the moisture absorption reaches a saturated state, the material absorbs and releases moisture repeatedly, resulting in an equilibrium state as if breathing. As described above, in the equilibrium state, not only moisture is absorbed but also moisture is released, so that it is possible to maintain a constant humidity. The humidity maintained at a constant level depends on the type of the highly absorbent material, that is, the type of the water-soluble polymer constituting the highly absorbent material, the type of the metal ion, the amount of the mixed metal ion, It can be adjusted by changing the impregnation amount or the like.

Hereinafter, the metal ion and the water-soluble polymer will be specifically described.

Examples of the metal ion used for the material having high moisture absorption / release properties include lithium ion, calcium ion, iron ion, aluminum ion, magnesium ion, chromium ion, cobalt ion, cadmium ion, zinc ion, and nickel ion.

Examples of metal salts that provide these metal ions include, for example,
Calcium chloride [CaCl ₂ ], iron (III) chloride hexahydrate [FeCl
₃ (6H ₂ O)], aluminum nitrate (III) hydrate [Al (NO
₃ ) ₃ (9H ₂ O)], magnesium chloride hexahydrate [MgCl ₂ (6H
₂ O)], zinc chloride [ZnCl ₂ ], chromium (III) chloride hexahydrate [CrCl ₃ (6H ₂ O)], cobalt (II) chloride hexahydrate [CoCl ₂
(6H ₂ O)], cadmium (II) nitrate tetrahydrate [Cd (NO ₃ )
₂ (4H ₂ O)], nickel (II) chloride hexahydrate [NiCl ₂ (6H ₂ O
O)] and one or more of lithium chloride [LiCl] and the like are preferably used. However, it is not limited to the above-mentioned metal salts, and chlorides, sulfates, acetates, nitrates, and other salts other than the above-mentioned metal salts may be used as long as they are salts composed of the above-mentioned metal ions. it can. Of the above metal salts, calcium chloride having deliquescence exhibits particularly excellent high moisture absorption / release properties.

As the mixing ratio of the metal salt with respect to the water-soluble polymer increases, it may be considered that higher hygroscopicity is obtained.However, since the solubility of the metal salt with respect to the aqueous polyvinyl alcohol solution is reduced, the metal ion is reduced. The metal ions cannot be highly dispersed, and the metal ions come into contact with each other, so that the hygroscopic effect of the metal ions is reduced. On the contrary, the hygroscopicity may be deteriorated in the initial stage.

On the other hand, when the mixing ratio of the metal salt is low, the amount of metal ions itself is small, so that the moisture absorbing ability is inferior.

Therefore, the mixing ratio of an appropriate metal salt is different depending on the type of the metal salt. For example, when calcium chloride [CaCl ₂ ] is used as a metal salt and polyvinyl alcohol is dissolved in water as a water-soluble polymer to form a 10% aqueous solution, the mixing ratio of calcium chloride is 20 mol per hydroxyl group of polyvinyl alcohol. % Or more, and more preferably 40 mol% or more. It should be noted that even if the mixing ratio of calcium chloride exceeds 100 mol%, the moisture absorption rate hardly changes. Therefore, it is not necessary to mix 100 mol% or more, and it is necessary to mix calcium chloride at 40 mol% to 100 mol%. preferable.

The metal salt may be one kind, or two or more kinds may be mixed.

In the present invention, since a water-soluble polymer is used, water is used as a solvent, so that there is little danger such as toxicity and explosiveness in a drying process in a manufacturing process, and there is an advantage that it is easy to handle.

As described above, the water-soluble polymers that can be used in the present invention include natural polymers, semi-synthetic polymers, and synthetic polymers. For example, natural polymers include starch, mannan,
There are seaweed, plant mucilage, microbial mucilage, protein and the like. Examples of semi-synthetic polymers include cellulose-based and starch-based. Examples of the synthetic polymer include polyvinyl alcohol, sodium polyacrylate, polyethylene oxide, and polyvinylpyrrolidone.

Among them, polyvinyl alcohol and polyvinylpyrrolidone have good compatibility with metal salts and poorly water-soluble polymers,
It is preferably used.

When using polyvinyl alcohol, completely saponified polyvinyl alcohol or partially saponified polyvinyl alcohol having a saponification degree of 90 mol% or less may be used.

When partially saponified polyvinyl alcohol is used as the water-soluble polymer of the present invention, the fluidity during moisture absorption can be further suppressed. It is considered that the action of suppressing the fluidity is due to the action of the hydroxyl group and the acetyl group present in the partially saponified polyvinyl alcohol. In other words, since the hydroxyl group has a high affinity for water, it is easy to gather around the metal salt that hydrates and retains water, while the acetyl group has a lower affinity for water than the hydroxyl group, There is not much existing around the metal salt. Since the acetyl groups of the partially saponified polyvinyl alcohol are easily arranged outside as described above, it is considered that the fluidity during moisture absorption is suppressed. When the fluidity is suppressed by using partially saponified polyvinyl alcohol, the degree of saponification is preferably 90 mol% or less and 70 mol% or more. 90 saponification degree
If it is at least mol%, it will be insufficient to suppress fluidity during moisture absorption, and if the saponification degree is at most 70 mol%, it will be difficult to sufficiently dissolve the metal salt.

The degree of polymerization of polyvinyl alcohol is not particularly limited because it does not particularly affect the moisture absorption / release properties.

An example of a method for producing a highly hygroscopic material using the above water-soluble polymer and metal salt is as follows.

Select the water-soluble polymer and metal salt to be used.

Dissolve the water-soluble polymer in water to make a 10% aqueous solution.

This aqueous solution is mixed with a metal salt and stirred at room temperature for 2 to 3 hours to obtain a viscous liquid.

The respiration material (2) can be obtained by mixing an aqueous emulsion of a poorly water-soluble polymer with the highly moisture-absorbing and desorbing material thus obtained and drying. This poorly water-soluble polymer is used for the form stability of the moisture-proof sheet (1) and the breathing material itself. If only the highly moisture-absorbing and desorbing material is adhered to the moisture-proof sheet (1), it is only due to the adhesive force of the water-soluble polymer. However, the material obtained by mixing the water-insoluble polymer emulsion and the aqueous solution of the highly moisture-absorbing and desorbing material as described in the present invention, stirring, and then drying is a highly moisture-absorbing and desorbing material. Sheet (1) is fixed by a poorly water-soluble polymer,
Almost no morphological change occurs even under high humidity.

In addition, since the surface of the wall covering of the present invention has many micropores as described above, it is presumed that moisture is absorbed through the micropores, and the hygroscopic property of the high moisture absorption / release material itself is reduced. There is no hindrance at all. Furthermore, since the wall covering of the present invention is surrounded by a poorly water-soluble polymer that does not like moisture, moisture can be immediately transferred to the highly moisture-absorbing and releasing material, and moisture can be absorbed more efficiently.

In the present invention, only a wall covering material having uneven hygroscopicity can be obtained unless an emulsion of a poorly water-soluble polymer is mixed with a viscous liquid of a highly hygroscopic material and dispersed uniformly. For this reason, it is necessary to use a common solvent for both, but since water is used as the solvent for the highly hygroscopic material, it is desirable to use an aqueous emulsion for the poorly water-soluble polymer.

Such poorly water-soluble polymers include phenolic resins, epoxy resins, acrylic resins, vinyl resins, urea and melamine resins, polyester resins, styrene resins,
Silicon resin, polyethylene resin, polyamide resin, urethane resin, or the like can be used. However, the present invention is not limited to these poorly water-soluble polymers, and it is sufficient that these poorly water-soluble polymers are stably present as an aqueous emulsion. Among these, it is preferable to use a vinyl resin, and among these vinyl resins, it is most preferable to use a vinyl chloride resin having a strong cohesive force.

Although the concentration of the water-based emulsion is not particularly limited, the weight ratio of the highly hygroscopic material after drying is 1%.
In this case, the concentration is preferably such that the proportion of the poorly water-soluble polymer becomes 1 to 10. This is because, if the proportion of the poorly water-soluble polymer is less than 1, the material becomes poor in strength and has no morphological stability despite the use of the poorly water-soluble polymer. If the proportion of the molecules is more than 10, uniform dispersion of the highly moisture-absorbing / desorbing material and the poorly water-soluble polymer emulsion itself becomes impossible. Particularly in this range, the ratio of the poorly water-soluble polymer to the highly moisture-absorbing and releasing material 1 is preferably 2 to 6.

The breathing material (2) thus obtained is laminated on the moisture-proof sheet (1). As the lamination method, the breathing material (2) may be directly applied to the moisture-proof sheet (1) in a viscous liquid state, and then dried to form a breathing material layer.
After the breathing material (2) is formed, the binder may be disposed in a dot-like manner so as to be laminated and integrated. In the latter case, the breathing material (2) may be in the form of a film obtained by simply drying, or may be dried after being impregnated in a fibrous material or the like. When impregnated into fibrous materials,
Since the poorly water-soluble polymer is aggregated and fixed at the intersection of the fibers, a respiratory material layer having excellent strength is obtained.

It is the moisture-proof sheet (1) that the breathing material (2) of the present invention is laminated. This moisture-proof sheet (1) prevents the moisture absorbed by the breathing material (2) from being released to the wall side,
Works to prevent internal condensation.

Examples of the resin constituting the moisture-proof sheet (1) include phenol resin, epoxy resin, acrylic resin, urea and melamine resin, polyester resin, styrene resin, silicon resin, polyethylene resin, polyamide resin, urethane resin, vinyl resin, and the like. What is impermeable to moisture can be used. Among these, a sheet made of a vinyl resin, especially a vinyl chloride resin is the most used sheet because it is versatile and inexpensive.

By laminating a breathable surface material (4) on the breathing material side to the wall covering material obtained by laminating the moisture-proof sheet (1) and the breathing material (2) thus obtained, the surface is not stained, It can be a wall material excellent in design. Since the breathing material (2) of the wall covering material in which the breathing material (2) and the moisture-proof sheet (1) are laminated absorbs and releases moisture in a saturated state, there is a certain amount of moisture even if fluidity does not occur. , Dust easily adheres to it. Therefore,
By laminating the air-permeable surface material (4), ventilation of moisture is not hindered, so that the effect of preventing dew condensation is not affected, and dirt can be hardly attached.

As such a surface material (4), paper such as rayon paper, non-woven fabric, woven fabric, knitted fabric, moisture permeable membrane and the like can be used.

Examples will be described below, but the present invention is not limited to the following examples.

[Examples] (Examples 1 to 4) Polyvinyl alcohol having a saponification degree of 90% was dissolved in water to obtain a 10% by weight aqueous solution, and then 60 mol% of calcium chloride was mixed with the hydroxyl groups of the polyvinyl alcohol. The mixture was stirred for 3 hours to obtain a highly hygroscopic material dispersed in a colloidal state.

Next, using an aqueous vinyl chloride resin emulsion having a concentration of 42% by weight, the vinyl chloride resin and the highly hygroscopic material were mixed at a dry weight ratio of 4: 1 and stirred for 3 hours to obtain a uniformly dispersed sol. The respiratory material (2) was obtained.

This respiratory material (2) was coated on a moisture-proof sheet made of a vinyl chloride resin at a dry weight of 30 g / m ² to obtain a wall covering (Example 1).

20 g / m ² (Example 2), 40 g / m ² (Example 3), 50 g / m ² (Example 4) of the same breathing material (2) as in Example 1 on the same moisture-proof sheet in dry weight. Coating was performed to obtain a wall covering.

Breathing material side of the wall covering (Example 5) Example 1 to obtain a wall covering surface material (4) by laminating rayon paper having a basis weight of 25 g / m ^2.

(Comparative Example) The same sol-like respiratory material (2) as in Example 5 was applied on a glass nonwoven fabric with a basis weight of 100 g / m ² obtained by a wet method at a dry weight of 30 g / m ² , and the same surface as in Example 5 was applied. The material (4) was laminated to obtain a two-layer wall covering material.

(Moisture Proof Test) The wall covering materials of Example 5 and Comparative Example were used on one side of a cubic box made of plastic having a side of 30 cm, and this box was heated at a temperature of 20 cm.
℃, 80% humidity in a constant temperature and humidity room, 0.5, 1, 2,
After 3, 5, and 24 hours, the humidity in the box was measured, and a moisture proof test was performed. The initial humidity in the box was 48%, and the measurement results are shown in Table 1.

From this table, it can be seen that the wall covering material of Example 5 has excellent moisture-proof properties.

(Hygroscopicity test) By leaving the wall covering materials of Examples 1 to 4 in a constant temperature / humidity room at a temperature of 20 ° C and a humidity of 65%, 1, 2, 3, 5,
The moisture absorption after 24 hours was measured.

 Table 2 shows the results of the hygroscopicity test.

Since the amount of moisture absorption increases in proportion to the amount of the breathing material (2) applied, the amount of moisture absorption can be adjusted by the amount of application.

Next, the wall covering materials of Examples 1 and 5 were allowed to stand in two types of constant temperature and humidity chambers at a temperature of 20 ° C. and a humidity of 65% and 80%.
Table 3 shows the results of examining the influence of the amount of moisture absorption caused by laminating the surface material (4) by measuring the amount of moisture absorption after 5 and 24 hours.

As can be seen from the table, the lamination of the water-absorbing rayon paper improved the moisture absorption and was preferable as a wall covering material.

[Effect of the invention] Since the wall covering material of the invention uses a moisture-proof sheet,
Moisture does not pass through the wall covering and cause internal condensation.
In addition, since moisture absorption and desorption are continuously generated by the breathing material, surface dew condensation does not occur.

When the water-insoluble polymer and the moisture-proof sheet are made of vinyl chloride resin, the versatility is excellent.

Further, if a surface material having moisture permeability is laminated on the surface of the breathing material, it becomes a wall covering material which is less likely to be stained and has an excellent appearance.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a wall covering of the present invention. FIG. 2 is a cross-sectional view of a wall covering laminated with a surface material. Wall 4, Surface material 5 Moisture flow

Claims (3)

(57) [Scope of request for utility model registration] 1. A moisture-proof sheet (1) is provided on one surface of a breathing material (2) comprising a mixture of a highly moisture-absorbing and releasing material in which metal ions are contained in a colloidal state in a water-soluble polymer and a poorly water-soluble polymer. A wall covering characterized by being laminated. 2. The wall covering according to claim 1, wherein the water-insoluble polymer and / or the moisture-proof sheet (1) is a vinyl chloride resin. 3. The wall covering according to claim 1, wherein a surface material having moisture permeability is laminated on the breathing material side of the wall covering according to claim 1.