JPH0222045A - Moisture permeable and moisture condensation preventive wallpaper, and preparation thereof - Google Patents

Abstract

PURPOSE:To obtain the title wallpaper having moisture condensation preventive effect and excellent in antistaining properties by laminating and fixing a moisture permeable resin foam layer composed of a closed cell structure to the surface of decorative paper while laminating and fixing base paper to the rear of said decorative paper. CONSTITUTION:A moisture permeable resin layer 1 or a resin foam layer 1 substantially composed of closed cells 5 is laminated and fixed to the surface of decorative paper 2. Therefore, moisture in the atmosphere passes through the relatively thin moisture permeable resin layer 1 to enter the interior of this laminated structure in the thickness direction within a short time. When a moisture absorbent 6 is dispersed in the decorative paper 2 or the resin layer 1, said moisture is rapidly absorbed. When an adhesive layer 3 has moisture permeability, moisture is further propagated to base paper 4 through the adhesive layer 3 to be absorbed by said base paper 4. Since much moisture is absorbed if the moisture absorbent 6 is dispersed in the adhesive layer 3, still more effect is obtained. Contrarily, when a room becomes a dry state, excellent moisture absorbing and discharging characteristics are again developed through the moisture permeable resin layer 1 and, as a result of this respiration action, a moisture condensation phenomenon on a wall surface is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This invention relates to a moisture-permeable anti-condensation wallpaper and a method for producing the same.

[Conventional technology]

Wallpaper is generally made of materials such as paper, fiber, plastic, and metal foil, and is a sheet-like flexible material that is applied as a finishing material to the walls and ceilings of buildings. It is a common name for something that has gender.

(Problems to be solved by the invention) Recent architectural styles have become Westernized with panels, prefabricated structures, and reinforced concrete, and the development of metal sash windows has improved the airtightness between indoors and outside air, but indoor ventilation has become poor. As a result of this phenomenon, the problem of condensation on walls has arisen.

In other words, the problem of condensation on the walls of closed rooms is not only the above-mentioned problem of the airtightness of the window sash, but also the increase in the amount of water used in daily life due to improved living standards, and the generation of moisture due to the use of heating appliances such as kerosene stoves and gas stoves. This is thought to be one of the causes.

By the way, this problem can be solved by inserting a heat insulating material inside the wall as a wall to prevent condensation to prevent the temperature of the wall surface in the room from dropping below the dew point. In order to maintain the performance of wood and prevent stuffiness caused by moisture inside walls, materials that are moisture permeable or air permeable have recently been attracting attention. Another required performance for wall materials is, of course, that they are resistant to stains due to condensed water, but even if condensed water does get on it, it must be made of a material that can be easily wiped off.For example, paper yarn wallpaper Like textile wallpaper, it has moisture absorption and desorption properties, but it gets dirty easily and has a microporous surface, which makes it susceptible to mold growth.
It is also difficult to wipe off the adhered dirt. Therefore, these materials do not have sufficient properties for the above-mentioned wallpaper.

Furthermore, as an improved version of this wallpaper, a wallpaper using a microporous film as a surface layer has been developed. However, this surface film has a large number of micropores that allow moisture to pass through, but water cannot pass through, and it becomes clogged with lumps, dirt, and other dirt, and is difficult to remove. The above-mentioned required properties of wallpaper, such as reduced moisture respiration, have not been fully satisfied.

In addition, as methods for manufacturing this type of microporous film, there are the so-called wet method, in which the solvent and water are replaced after spreading the solution, and the so-called dry method, in which micropores are created mechanically and physically. All of these manufacturing processes are complex and require special mechanical equipment, and in addition, when applying this type of film to the skin layer of wallpaper, it is necessary to laminate and fix it to the decorative paper using an adhesive. there were.

Additionally, attempts have been made to prevent dew condensation on the wallpaper surface by adding a polymer moisture absorbent to vinyl chloride resin wallpaper. However, in this type of wallpaper, the moisture absorbent exposed on the surface layer absorbs moisture well, but the moisture absorbent buried inside is covered with non-breathable vinyl chloride resin, so its moisture absorption ability is limited. severely inhibited,
Moreover, for the same reason, moisture that has been absorbed by the wallpaper is difficult to release, resulting in a wallpaper with poor moisture absorption and release capabilities as a whole.

The purpose of this invention is to
To provide a moisture-permeable dew-condensation-preventing wallpaper that is effective in preventing dew condensation and has excellent stain resistance. A further object of the present invention is to provide a method for producing the above-mentioned moisture-permeable wallpaper, which has simple steps and does not require special mechanical equipment.

[Means to solve the problem]

This invention provides a moisture-permeable resin layer or a moisture-permeable resin foam layer consisting of substantially closed cells to improve the texture on the surface of the decorative paper, and a moisture-permeable adhesive, preferably on the back surface of the decorative paper. The present invention relates to a moisture permeable anti-condensation wallpaper characterized by laminating and fixing a backing paper.

Furthermore, this invention provides a method for producing wallpaper having a moisture-permeable resin layer and a mount bonded with a moisture-permeable adhesive. A method for producing moisture-permeable anti-condensation wallpaper is adopted, which is characterized by applying it to the surface of paper and drying it by heating.

A method for manufacturing wallpaper in which a layer of moisture-permeable resin foam is laminated and fixed is that thermally expandable microcapsules made by embedding a vaporizable liquid in a thermoplastic resin film are uniformly coated with a moisture-permeable resin and, if necessary, a moisture-absorbing agent. A suitable method is to apply the compound obtained by mixing onto the surface of decorative paper, heat and foam it, and then fix it to the backing paper with an adhesive.

In addition, the adhesive for fixing the mount and the decorative paper is moisture permeable, and it is preferable to uniformly mix a moisture absorbent with the adhesive because it will further improve moisture absorption and desorption performance and dew condensation prevention performance. The present invention also separately employs such a configuration.

By the way, the thermally expandable microcapsules used in this invention are microspheres in which a vaporizable liquid is embedded in a thermoplastic resin film.
When heated to an appropriate temperature, the liquid embedded inside vaporizes, and the pressure causes the entire capsule to expand, creating a foam with expanded volume (hereinafter abbreviated as foaming). The thermoplastic resin constituting the microcapsules has a temperature of 50°C to 20°C.
A resin having a softening point of 0'C is preferable, and examples of this type of resin include homopolymers such as polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, polymethyl acrylate, polymethyl methacrylate, and polyvinyl acetate, or copolymers thereof. I can give an example.

As the vaporizable liquid to be embedded, lower hydrocarbons such as liquid butane, which can be easily microencapsulated and are inexpensive, are suitable. The particle size of microcapsules before foaming is 5 to 3.
It has a property of foaming several times to several tens of times when heated at 50 to 200°C for several minutes.

The moisture-permeable resin used in this invention is not particularly limited as long as it is soluble in solvents, does not easily swell in water, and has film-forming ability, but examples include vinyl alcohol resins, acrylic resins, etc. Resin, urethane resin, amino acid resin, etc., and the moisture permeability of the film (film thickness 10μ) measured by JIS Z-0208B method is 10
00g/Tn2.24 or more is suitable.

These resins are usually used by dissolving them in organic solvents, but
In this case, the solid content in the solution is adjusted to 10 to 50% by weight, and the solution viscosity is adjusted to 100 to 5000 cps.

Next, heat-expandable microcapsules and, if necessary, a moisture absorbent and other additives are suitably added to this solution and mixed uniformly to prepare a compound.

The mixing ratio of the thermally expandable microcapsules and the moisture permeable resin is in the range of 5 to 500 parts by weight of the microcapsules per 100 parts by weight of the resin solid content in the solution. If it is less than 5 parts by weight, it will lack a soft feel especially as wallpaper after foaming.
If it is more than 500 parts by weight, the strength of the moisture permeable resin foam layer will be low and the moisture permeability will also be impaired, which is not preferable. When mixing the microcapsules, it is important to uniformly mix and disperse them using an appropriate method such as daysilver, homodisper, or paint roll.

In this invention, the moisture absorbing agent added to the moisture permeable resin and adhesive may be various commercially available polymeric moisture absorbing agents or inorganic moisture absorbing agents that can exhibit moisture absorption and desorption performance depending on the environment. Any of these can be used, and they can be used alone or in combination. Preferred polymeric moisture absorbing agents include polyacrylate-based, carboxymethyl cellulose, isobutylene-maleic acid copolymer, starch-acrylic acid graft polymer, and vinyl acetate-based polymer.
Examples include saponified acrylic ester copolymers, saponified vinyl acetate-unsaturated dicarboxylic acid copolymers, and polyethylene oxide. The particle size of these polymeric hygroscopic agents is usually 20 μm or less, and the finer the particle size, the better the moisture absorption and desorption performance will be. In addition, bentonite, silica, sepiolite, calcined talc, zeolite, various other inorganic salts, and natural stone powder with adsorption properties are used as inorganic hygroscopic agents, but the finer the particle size, the larger the surface area, and the more absorbent. It is preferable because it has good moisture release performance. The amount of these moisture absorbers added is usually 10 to 30 parts by weight per 100 parts by weight of resin solid content in the solution.
It is used in a range of 0 parts by weight, and is selected so as to maximize the moisture absorption and desorption performance of the wallpaper as long as it does not interfere with other properties.

In carrying out this invention, in addition to the above-mentioned compounding agents, various pigments, weathering agents, deodorizing agents, fragrances, antifungal agents, and the like may be added as appropriate.

As a method for coating the decorative paper with the compound prepared by mixing the various formulation components as described above, generally known coating methods such as gravure coating, doctor blade coating, reverse roll coating, etc. are appropriately employed. Decorative paper printing is expressed as a printed body of various colors and patterns, and is printed on the surface with water-based, oil-based, or other ink.

The decorative paper may be made of natural or synthetic materials, and pulp paper, asbestos paper, etc. are usually used, and it is used in the form of woven or non-woven fabrics. They also need to have moisture absorption and desorption properties. The thickness of this decorative paper is appropriately selected depending on the place where the wallpaper is used, but is generally 50 to 300 microns. The compound is continuously coated onto the decorative paper to a constant thickness of 10 to 100 μm, heated and dried to scatter the solvent, and then cooled to complete the molding. Drying temperature is usually 50'C ~
200'C is used. Further, in the case of a compound containing a foaming agent, when heated to a predetermined temperature, the microcapsules foam to form a moisture-permeable resin foam layer with a thickness of 50 to 1000 μm. The heating temperature during foaming is appropriately selected depending on the material of the microcapsules used, but 50 to 200'C is usually used, and heating at this temperature for several minutes (for example, 120'C for 1 minute) will remove the solvent. Foaming occurs at the same time as the particles are scattered, and the molding is then completed by cooling. In addition, the process of blowing off the solvent and the foaming process are separated,
It can also be molded in two stages. Foaming may be done by free foaming, but it is also possible to control the foaming thickness by pressing from above using a suitable method through a release paper.

Moreover, if the decorative paper coated or foamed with a moisture-permeable urethane resin is embossed, the appearance as wallpaper will be improved. Next, a mount is laminated and fixed to the back surface of the laminated and fixed moisture-permeable resin layer with a moisture-permeable adhesive as a structure for pasting it on the wall surface of a building, etc., thereby forming the moisture-permeable dew condensation-preventing wallpaper of the present invention. . Embossing may be performed after laminating the mounts.

As the mount used in this invention, flame-retardant pulp paper is usually used, but pulp paper without flame-retardant treatment, processed pulp paper, and a mount made of organic or inorganic synthetic paper or nonwoven fabric may also be used. The thickness of these mounts is usually 100 to 100
It must have a diameter of 0μ, be able to be unwound, and have a certain degree of flexibility. The reason for laminating the mounts is that clear printing is impossible when decorative printing is performed on the mounts.

Adhesives for fixing the mount and decorative paper include vinyl acetate, starch, or a mixture of these, acrylic and copolymer, urethane, vinyl alcohol, and amino acid adhesives. The agent meets JIS Z-0208 from the viewpoint of preventing dew condensation and improving moisture absorption and release properties.
A film having a moisture permeability of 500 g/Tr12·248 or more when made into a film (film thickness 10 μm) measured by method B is suitable.

(Function) As described above, the wallpaper according to the present invention has a structure in which a moisture-permeable resin layer or a resin foam layer consisting of substantially closed cells is laminated and fixed on the surface of decorative paper, so that moisture in the atmosphere can pass through. If the moisture absorbent is dispersed in the decorative paper or the resin, it will be quickly absorbed by the adhesive, making it moisture permeable. If the adhesive layer has a moisture-permeable adhesive layer, this moisture is further propagated to the mount, where moisture is absorbed.Furthermore, if a moisture absorbent is dispersed in the adhesive layer, the moisture absorption agent Since it absorbs more moisture, the - layer effect is improved. Conversely, when the room becomes dry, the absorbed moisture is quickly released again through the moisture-permeable resin layer, resulting in excellent absorption. It exhibits moisture release properties and has a moisture buffering function that can closely follow changes in indoor temperature, and as a result of this breathing action, condensation on walls is suppressed.It also maintains a constant humidity in the palace. When the moisture permeable resin layer becomes a foam layer due to micro balloons,
Not only does it have an insulating effect, preventing condensation, but it also improves the texture of the skin.

Furthermore, the surfaces of the moisture-permeable resin layer and moisture-permeable resin foam layer of this wallpaper are substantially non-porous, so even if dirt adheres to them during use, they will not clog and can be easily cleaned with a dry cloth or wet cloth. It has many advantages such as being able to be washed and not reducing moisture permeability.

When the thus obtained wallpaper is used in combination with a suitable heat insulating material such as phenol board, urethane board, or polystyrene board, the dew condensation prevention effect can be further enhanced.

(Example) (Example 1) Polyethylene glycol (average molecular weight 400) and isophorone diisocyanate were polymerized by heating in a conventional manner, and the obtained urethane polymer was dissolved in a toluene isopropanol mixed solvent (weight mixing ratio 1:1). solid content 25% by weight
A urethane polymer solution was prepared. The moisture permeability of a 20μ thick film made from this solution by the casting method is 4300 (J/m2・24H.Tweet,
L, (7) The 2S liquid was applied uniformly onto decorative paper (thickness 180μ) using the gravure coating method, dried by heating at 120'G for 1 minute in a heating oven, and then cooled to form the decorative paper. A moisture-permeable resin layer was laminated and fixed on the surface to a thickness of 200 μm. A 320 μm thick wallpaper was obtained by adhering a flame retardant mount (120 μm) to the back side with a starch adhesive. FIG. 1 is a sectional view showing the structure of a moisture-permeable anti-condensation wallpaper obtained by the above method.

In the figure, 1 is a moisture-permeable resin layer, 2 is a decorative paper, 3 is an adhesive, and 4 is a flame-retardant mount for wallpaper.

(Example 2) In Example 1, thermally expandable microcapsules (trade name: Microsphere-F-50) were added to a urethane polymer solution with a solid content of 25% by weight per 100 parts by weight of solid content in the solution.
D, manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd., was added at a ratio of >50 parts by weight and mixed uniformly using a paint roll to prepare a compound.

This compound was applied uniformly onto decorative paper (thickness 180μ) using the gravure coating method, and then heated in a heating oven for 12 hours.
After heating and foaming at 0° C. for 1 minute, the paper was cooled to form a moisture-permeable resin foam layer made of substantially closed cells on the surface of the decorative paper and fixed to a thickness of 300 μm. A 430 μm thick wallpaper was obtained by adhering a flame retardant mount (120 μm) to the back side with a urethane adhesive.

FIG. 2 is a sectional view showing the structure of the moisture-permeable anti-condensation wallpaper obtained by the above method.

In the figure, numerals 1 to 4 are the same as in FIG. 1, and 5 is a closed cell.

(Example 3) In Example 1, 50 parts by weight of thermally expandable microcapsules and a moisture absorbent (manufactured by Kuraray Co., Ltd., K1 Glue) were added to a urethane polymer solution with a solid content of 25% by weight per 100 parts by weight of solid content in the solution. ) was added at a ratio of 30 parts by weight to prepare a compound, and a moisture permeable foam layer was laminated and fixed on decorative paper in the same manner as in Example 2 to give a thickness of 280 μm. A 410 μm thick wallpaper was obtained by adhering a flame retardant mount (120 μm) to the back side with a starch adhesive.

FIG. 3 is a sectional view showing the structure of a moisture-permeable wallpaper obtained by this method.

In the figure, numerals 1 to 5 are the same as in FIG. 2, and 6 is a moisture absorbent.

(Example 4) A moisture-permeable foam layer was laminated and fixed on decorative paper in the same manner as in Example 3 using the same compound to give a thickness of 280 μm. A flame-retardant mount for wallpaper is made of a compound obtained by uniformly mixing urethane adhesive and a polymer moisture absorbent (Sumikagel, manufactured by Sumitomo Chemical Co., Ltd., 30 parts by weight) per 100 parts by weight of the solid content on the back side. A wallpaper with a thickness of 410 μm was obtained.

FIG. 4 is a sectional view showing the structure of a moisture-permeable anti-condensation wallpaper obtained by this method. In the figure, the numbers 1 to 6 are the second
Same as the figure.

(Example 5) Example 5 was prepared by using an EVA-based adhesive having no moisture permeability in Example 1.

Regarding the wallpaper according to each of the above examples, a moisture permeability test, a dew condensation test, a wiping test, and a moisture absorption/release test were conducted using the following methods. The results are shown in Table 1 and Figure 5.

For comparison, a commercially available vinyl chloride wallpaper containing no moisture absorbent, a commercially available banknote paper, and a commercially available dew-preventing vinyl chloride wallpaper containing a polymeric moisture absorbent were tested in the same manner as Comparative Examples 1.2.3.

Moisture permeability test: Based on JIS Z-0208B method.

Condensation test: Paste wallpaper as a test specimen on the entire outer side of a rough tin can with a content of 500 m and g using vinyl acetate adhesive, fill the can with ice water, and apply 20'CX50%R.
The time required for dew to begin to form on the wallpaper surface (dew condensation time) when the wallpaper was placed in an atmosphere of H was measured.

Moisture absorption/desorption test; wallpaper as a test specimen was 1Qcm x 10cm
Cut into m squares and paste aluminum tape on the back side of the mount to prevent water vapor from penetrating from the back side at 40°C x 90% R.
After measuring the change over time in the amount of water absorbed by the wallpaper when placed in an atmosphere of
%RH atmosphere, and the time-dependent change in weight loss due to moisture release was measured over 24 hours.

Wiping test: After soaking the sheet with soy sauce for 30 minutes at room temperature, it was wiped with a cloth dampened with water and observed 24 hours later. ○: No contamination at all.

△・・・Slightly contaminated, ×: Contaminated.

As shown in Table 1 and FIG. 5, the wallpaper of the present invention has a longer dew condensation time than commercially available vinyl chloride wallpapers, and has a good non-sticky surface when water is absorbed compared to commercially available paper wallpapers. It exhibits moisture absorption and desorption performance, has excellent stain resistance, and is recognized as a well-balanced wallpaper in terms of performance. In particular, when a hygroscopic adhesive is used, the condensation time is significantly prolonged.

〔Effect of the invention〕

According to the wallpaper of the present invention, it is possible to obtain a wallpaper that is effective in preventing dew condensation, has excellent stain resistance, can express a texture, and has moisture permeability. In addition, the manufacturing process is simple and does not require special equipment, and can be manufactured at a relatively low cost, so it is excellent in economy, workability, and productivity.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of an example of the moisture-permeable anti-condensation wallpaper of this invention, Figs. 2 to 4 are sectional views of the wallpaper of this invention before implementation, and Fig. 5 is an embodiment of the invention. It is a graph showing the moisture absorption and desorption performance measured for wallpaper of a comparative example.

Claims (6)

[Claims] (1) Moisture-permeable condensation characterized by having a structure in which a moisture-permeable resin foam layer consisting of substantially closed cells is laminated and fixed on the surface of the decorative paper, and a mount is further laminated and fixed on the back side of the decorative paper. Prevention wallpaper. (2) The moisture-permeable dew condensation-preventing wallpaper according to claim 1, which is laminated and fixed with a moisture-permeable adhesive. (3) Heat-expandable microcapsules made by embedding a vaporizable liquid in a thermoplastic resin film, a moisture-permeable resin, and, if necessary, a moisture absorbent, are mixed uniformly, and the resulting compound is applied to the surface of the decorative paper. Claim 1, characterized in that the adhesive is applied to the substrate, heated and foamed, and further fixed to the mount with an adhesive.
Or the method for producing a moisture-permeable anti-condensation wallpaper according to 2. (4) A moisture-permeable resin layer mainly composed of moisture-permeable resin is laminated and fixed on the surface of the decorative paper, and a mount is further fixed on the back side of the decorative paper with a moisture-permeable adhesive. Features moisture permeable anti-condensation wallpaper. (5) Moisture-permeable dew condensation prevention according to claim 4, characterized in that a compound obtained by uniformly mixing a moisture-permeable resin and, if necessary, a moisture absorbent, is applied to the surface of the decorative paper and dried by heating. How to make wallpaper. (6) The moisture-permeable dew condensation-preventing wallpaper according to claim 2 or 4, wherein a moisture-absorbing agent is uniformly mixed with a moisture-permeable resin as an adhesive for fixing the back side of the decorative paper and the mount.