JPH0364304B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a method for producing a dew-preventing foam decorative material used for wall covering materials, ceiling materials, etc. <Prior art> Known methods for imparting dew condensation prevention effects (moisture permeability) to decorative materials using synthetic resins can be roughly divided into:
There are three methods: In other words, one is JP-A-Sho.
As disclosed in Japanese Patent Application Laid-open No. 56-3302, one method is to mix a water-absorbing polymer into a synthetic resin, and the other is to mix a water-absorbing polymer into a synthetic resin, as disclosed in Japanese Patent Application Laid-open No. 53-31772, to create numerous interconnections. Another method is to provide a foamed layer with microscopic cells that provide moisture permeability, as described in Japanese Patent Publication No. 53-38102, using an olefin-based microporous sheet. In addition, air permeability and moisture permeability were also ensured by mechanically punching fine holes using a cloth roll. <Problems to be Solved by the Invention> Since these decorative materials are mainly used as interior wall covering materials, they are usually given an uneven pattern by mechanical embossing. The dew condensation prevention effect (moisture permeability) was significantly impaired and the desired function could not be achieved. In the method of mixing water-absorbing polymers into the synthetic resin layer, the water-absorbing effect only works on the water-absorbing polymers exposed on the surface, but when mechanical embossing is applied to obtain a decorative design, The exposed area of the water-absorbing polymer exposed on the surface became narrow, or in extreme cases it was crushed, making it impossible to expect the original dew condensation prevention effect. In addition, when a foamed layer with countless interconnected microscopic bubbles is mechanically embossed to ensure the design, the foamed synthetic resin layer melts due to the heating during embossing, and the interconnected microscopic bubbles form. Not only that, but also the mechanical pressure during embossing crushed the communicating microbubbles in the concave portions, so that the desired dew condensation prevention effect could not be obtained. Even if a microporous olefin sheet is used to provide moisture permeability, if mechanical embossing is applied to achieve a design, the heating during embossing may melt the micropores in the sheet and close them, causing the recesses to become clogged. The micropores were crushed, and the desired moisture permeability effect was significantly impaired. Even when punching is used, the holes may become clogged during embossing, or the holes can generally be made only larger than chemical microbubbles, which may impair the design or cause stains in the holes made by the clothing. It had disadvantages such as adhesion. <Means for Solving the Problems> Therefore, the present invention provides a concave foam layer in a final product using a foamable synthetic resin containing a water-absorbing polymer and a foaming agent that creates countless interconnected micro-cells after heating and foaming. Provided is a method for producing an extremely excellent dew-preventing foam decorative material having an uneven pattern, by using it for both the base layer forming the base layer and the pattern layer forming the convex foam layer, and combining this with a moisture-permeable resin coating. It is. In addition, although the conventional technology had a disadvantage in that the effect of preventing condensation in the concave portions was poor, according to the method of the present invention, the concave portions also have an extremely excellent dew condensation prevention function, and furthermore, both the concave portions and the convex portions are foamed. Since it is formed of layers, it has heat insulation and sound insulation effects, and any design pattern can be created without mechanical embossing, and the pattern formation does not have any negative effect on the dew condensation prevention effect. It is possible to provide a method for producing a foamed decorative material that prevents condensation. The present invention provides a first foamable synthetic resin containing a micropowdered water-absorbing polymer and a foaming agent that creates countless interconnected fine cells (open cells) after heating and foaming, on a base material such as paper. is laminated on the entire surface, and then, on the first foamable synthetic resin layer, a first foaming layer containing a water-absorbing polymer and a foaming agent that creates countless interconnected fine cells after heating and foaming. At least one second foamable synthetic resin colored in the same color or different color as the foamable synthetic resin layer is formed in an arbitrary pattern, and further a moisture permeable resin coating is formed on the first and second foamable synthetic resin layers. After forming the first and second foamable synthetic resins, the first and second foamable synthetic resins are heated and foamed to reveal a foamed uneven pattern having a function of preventing condensation. To explain in more detail below, the base material is:
Any material such as paper, cloth, nonwoven fabric, aluminum hydroxide paper, etc. can be used. On these base materials, by a known lamination method such as a coating method, a calender method, or a laminator method, a foaming agent containing a finely powdered water-absorbing polymer and a foaming agent that creates countless interconnected fine cells after foaming with heat is applied. A foamable synthetic resin layer of No. 1 is formed on the entire surface. As the resin used for this first foamable synthetic resin layer, any resin including heat-foamable vinyl chloride resin can be used. The water-absorbing polymer is a well-known hydrophilic resin capable of absorbing water and expanding, and desirably has the ability to absorb 50 times or more of its own weight of pure water. The main water-absorbing polymers include starch/sodium acrylate graft copolymers, saponified vinyl esters/ethylenically unsaturated carboxylic acids or their derivatives, polysodium acrylate crosslinkers, and polyvinyl alcohol/acrylate graft copolymers. Polymers, etc. can be fried. Commercially available products include Sumikagel-SP (Sumitomo Chemical),
Examples include Sunwet IM-300 (Sanyo Chemical Products) and Aqua Keep 4S (Steel Chemical Industry Products). These water-absorbing polymers usually have a particle size of 350μ
Although it is a fine powder of about ~0.1μ, an average particle size of 100μ or less is preferable in consideration of dispersibility. The number of parts added is usually 2 to 40 parts, preferably around 5 to 15 parts. The foaming agent contained in the above-described first foamable synthetic resin preferably has an open cell ratio of 70% or more after heating and foaming, from the viewpoint of preventing dew condensation. The ratio can be adjusted by adjusting the mixing ratio of the foaming agent for forming closed cells and the foaming agent for forming open cells (open cells), adjusting the foaming speed by selecting a stabilizer, or adjusting the foaming heating temperature and foaming heating time. It can be achieved.
The above-mentioned Japanese Patent Application Laid-Open No. 53-31772 describes a combination of a foaming agent (UNIFORM AZ-F Otsuka Pharmaceutical) and a stabilizer (Stabilizer F Kyodo Pharmaceutical), and a combination of a foaming agent (Onifain MO Otsuka Pharmaceutical) and any stabilizer. There is an example. In the case of the present invention, these materials can be used, and in the case of vinyl chloride resin, ordinary azodicarbonamide is often used, and the first foamable synthetic resin layer is coated on the entire surface of the base material. After the lamination, a second foamable synthetic resin paint is formed on top of it in an arbitrary pattern using a known coating printing method such as a rotary screen printing method or a gravure textile printing method. The second foamable synthetic resin layer is dried and semi-gelled. This second foamable synthetic resin also contains a water-absorbing polymer having the same or similar performance as that contained in the first foamable synthetic resin, and a foaming agent that creates countless interconnected fine cells after heating and foaming. However, the second foamable synthetic resin applied in a pattern may be colored the same or different color from the first foamable synthetic resin. Further, this second foamable synthetic resin may be of a single color, or may have a multicolor pattern from the viewpoint of aesthetic effect and design. When the first foamable synthetic resin is in the form of a paste paint and is to be laminated onto a base material by a coating method, the first foamable synthetic resin paint may be used as it is or a color pigment may be added to the second foamable synthetic resin. It is possible to use a foamable synthetic resin as a substitute, but the viscosity must be adjusted slightly lower in the case of rotary screen printing or gravure printing, which generally forms the second foamable synthetic resin paint into a pattern. There is.
In addition, by incorporating a large amount of filler into the first foamable synthetic resin, it is possible to reduce costs and improve the flame retardancy of wallpaper, etc. However, in the case of rotary screen printing and gravure textile printing, Since it is not possible to incorporate as much filler as the first foamable synthetic resin into the first foaming synthetic resin due to problems such as blurring, clogging, and viscosity during coating and printing, it is desirable to use separate fillers if possible. After laminating the first foamable synthetic resin on the entire surface of the base material and further forming the second foamable synthetic resin in a pattern on the base material, in order to form a moisture permeable resin coating thereon, a transparent A wet resin paint may be applied by a coating method, a surface treated with a gravure printing machine, or a pre-formed moisture permeable resin film may be laminated. As the moisture-permeable resin, for example, urethane-based W/O
Type emulsion resin, amino acid/methacrylic acid/
In addition to urethane copolymers, there are microporous sheets of the above-mentioned olefin resins, but they do not lose their moisture-permeable properties when heated at high temperatures for foaming, and also do not cause stains when used as decorative materials. In order to eliminate seepage of cleaning sewage that is removed when cleaning, it is preferable to use an amino acid/methacrylic acid/urethane copolymer that allows passage only in the form of water vapor but not in liquid form. It can also be used with moisture-permeable resin. Now, the first foamable synthetic resin is laminated on the base material,
Further, a second foamable synthetic resin is formed in a pattern on top of that, and a moisture-permeable resin film is further formed on the first and second foamable synthetic resin layers, and then heated in a foaming heating furnace. A foaming treatment is performed to reveal a foamed uneven pattern to obtain a foamed decorative material that prevents condensation. The condensation-preventing foam decorative material of the present invention having this uneven pattern has foam not only in the convex portions but also in the concave portions,
Furthermore, there are countless microbubbles that communicate with the convex and concave areas, and water-absorbing polymer is evenly mixed in, and a moisture-permeable resin film is formed on the surface of the convex and concave areas. It is something that exists. <Effects of the Invention> According to the method of the present invention, both the concave portions formed by foaming the first foamable synthetic resin layer and the convex portions formed by foaming the second foamable synthetic resin layer have countless It is a foamed synthetic resin layer that has microscopic cells that communicate with each other, and the foamed synthetic resin layer has finely powdered water-absorbing polymer mixed and scattered almost uniformly in the foamed synthetic resin layer.
A moisture permeable resin coating is formed on the surface of the foamed synthetic resin layer of the convex portion. Therefore, even if dew condensation occurs on the surfaces of both the concave and convex portions, the moisture will pass through the moisture-permeable resin coating and actively enter the continuous fine cells and water-absorbing polymer in the foamed synthetic resin layer of the concave and convex portions. Therefore, there is no possibility of condensation forming on the surfaces of both concave and convex portions. As mentioned above, the dew condensation-preventing foam decorative material of the present invention is not mechanically embossed at all, and the concave portions are also foamed, and it has a dew condensation prevention effect, compared to the conventional technology. It has extremely excellent functionality, and is also excellent in that a desired level difference in unevenness can be created by arbitrarily adjusting the lamination or coating thickness of each of the first and second foamable synthetic resins. In particular, this product is unique from conventional products in that the appearance of the uneven pattern does not interfere with the dew condensation prevention function. In the prior art, when the concave portion was designed to have a large area, the dew condensation prevention function naturally deteriorated, but the method of the present invention does not have such a drawback. That is, in the case of a design in which the area of the recessed part is large, it is possible to increase the lamination thickness of the first foamable synthetic resin that becomes the recessed foamed synthetic resin layer in advance; In the case of a narrow design, the laminated thickness of the first foamable synthetic resin that will become the foamed synthetic resin layer in the concave areas is set thin in advance, and the coating thickness of the second foamed synthetic resin that will become the foamed synthetic resin layer in the convex areas is set thin in advance. By making adjustments such as setting the thickness to be thicker in advance, it is possible to easily obtain the desired dew condensation prevention effect. In addition, when the unevenness level difference is set in advance from the design point of view, it may not be possible to adjust the lamination thickness or coating thickness of the first and second foamable synthetic resins, but in such a case, the method of the present invention Then, the amount of water-absorbing polymer added to the first foamable synthetic resin and the amount of water-absorbing polymer added to the second foamable synthetic resin may be adjusted to different amounts, or the water absorption performance may be adjusted to different amounts. By selecting and using different types of water-absorbing polymers, there is an advantage that the water-absorbing performance can be easily maintained and set at a desired level without being directly related to uneven steps. With conventional technology, it was impossible to achieve such water absorption performance by changing the composition of the concave and convex parts, but in the present invention, different types of water-absorbing polymers are selectively used for the concave and convex parts. In addition, the amount of the water-absorbing polymer added can be freely selected, and as described above, the lamination thickness or coating thickness of the first and second foamable synthetic resins can be set arbitrarily. It can be said that it is an extremely excellent product in that there is no need to worry about the dew condensation prevention effect being affected by design restrictions. Further, the amount of the blowing agent added to the first and second foamable synthetic resins to create countless interconnected micro-cells after heating and foaming may be varied, or different types of blowing agents may be selected. Alternatively, it is also possible to change the combination with the stabilizer, and the advantage is that it is easy to maintain and set the dew condensation prevention performance at the desired level while adjusting the unevenness depending on the amount and type of foaming agent added. The present invention has this feature, and is also superior to the prior art in this respect. <Example> A first foamable vinyl chloride resin compound having the following formulation was laminated to a flame-retardant paper (base material) 1 for wallpaper to a thickness of 0.15 mm by a calendar method, and a first foamable synthetic resin layer 2 was formed. was laminated over the entire surface (Fig. 1). Resin...Polyvinyl chloride resin 100 parts Plasticizer...DOP 50 parts Stabilizer...Ba-Zn system 3 parts Blowing agent...ADCA system 5 parts Water-absorbing polymer...Sumikagel SP-520 10 parts Filler...Calcium carbonate 70 parts Pigment... Titanium white 15 parts Rust inhibitor...Biocide 1.5 parts Next, on the first foamable synthetic resin layer 2, using a rotary screen multicolor printing machine equipped with a screen cylinder with a floral pattern, the following was printed. Formulated with foamable vinyl chloride resin paste paint
The second foamable synthetic resin layer 3 was formed in a floral pattern by applying the resin to a thickness of 0.12 mm and drying and semi-gelling it at a temperature lower than the decomposition temperature of the foaming agent (FIG. 2). Resin...Polyvinyl chloride resin 100 parts Plasticizer...DOP 50 parts Stabilizer...Ba-Zn system 3 parts Blowing agent...ADCA system 10 parts Water-absorbing polymer...Sunwet IM-300 8 parts Filler...Calcium carbonate 30 parts Face Material...Titanium white 10 parts Colorant...Red pigment 5 parts Rust preventive agent...Biocide 1.5 parts Next, using a gravure printing machine, amino acid/methacrylate was applied to the surface of the first and second foamable synthetic resin layers. A moisture-permeable resin coating layer 4 was formed by applying and drying a moisture-permeable resin coating consisting of an acid/urethane copolymer (FIG. 3). Next, this was introduced into a foaming heating furnace set at about 230°C and heated for 1 minute to foam the first and second foamable vinyl chloride resin layers.
The foamable synthetic resin layer 2 is foamed to form a concave foamed synthetic resin layer 5 with a thickness of approximately 1.2 mm, and the second foamable synthetic resin layer 3 is foamed in a floral pattern to form a convex portion approximately 1.5 mm thick. A foamed synthetic resin layer 6 was formed (fourth
figure). As can be seen from Fig. 4, the second convex portion
Since the synthetic resin layer 5 formed by the first foamed synthetic resin layer 2 exists below the synthetic resin layer 6 formed by the foamed synthetic resin layer 3, the total number of convexities seen from the surface of the base material is The thickness is approximately 2.7mm, and there are recesses and
A moisture-permeable resin coating 4 was formed on the surface of each of the convex portions. This condensation-preventing foam decorative material having an uneven pattern has both concave and convex portions foamed, and furthermore, from its cross section, the first and second foamable synthetic resin layers have numerous connections with the foamed synthetic resin layers 5 and 6. In addition, the water-absorbing polymer in the form of fine powder is almost uniformly mixed in, and the surface is covered with a moisture-permeable resin film 4, and there are no irregularities. Because the steps were large and the recesses were also foamed, it was a condensation-preventing foam decorative material with excellent heat and sound insulation properties. In this example, the second vinyl chloride resin paste paint to be formed into a pattern had a floral pattern with only one red color, but if necessary, the second vinyl chloride resin paste paint could be made in multiple colors. It is also possible to form it in a plurality of patterns. Incidentally, Table 1 shows the test results of a comparative study of the dew condensation prevention wallpaper of the present example and a conventional dew-preventing wallpaper having a similar uneven pattern.

【table】

[Table] As can be seen from Table 1, the examples obtained by the method of the present invention are synthetic resin layers in which the concave portions are also foamed, and there are not only countless communicating microbubbles, but also fine powder. The water-absorbing polymer particles were almost uniformly mixed and dispersed, and because they were not subjected to any mechanical embossing pressure, they were practically as effective in preventing condensation as the convex portions. In addition, when examining the cross-sectional view of the product of this example with a magnifying glass, it was found that the concave portion located below the convex portion and the convex portion above it were integrated during the foaming heat treatment, and the open cells in the concave portion and the convex portion were integrated. It was confirmed that the open air bubbles in the sections were almost connected, and that moisture (moisture) absorbed from the surface of the convex sections easily passed through to the concave sections.

[Brief explanation of drawings]

1 to 4 are cross-sectional views for explaining aspects of different stages of an embodiment of the manufacturing method of the present invention. 1...Flame retardant paper (base material), 2...First expandable vinyl chloride resin layer containing a water-absorbing polymer and a foaming agent that creates countless interconnected fine cells after heating and foaming, 3... A second material containing a water-absorbing polymer and a foaming agent that creates countless interconnected microbubbles after heating and foaming.
foamable vinyl chloride resin layer, 4... moisture-permeable resin coating, 5... foamed synthetic resin layer in which the first foamable vinyl chloride resin layer 2 is foamed, 6... second foamable vinyl chloride resin layer 3 is a foamed synthetic resin layer.

Claims (1)

[Claims] 1. A first foamable synthetic resin containing a finely powdered water-absorbing polymer and a foaming agent that creates countless interconnected microbubbles after heating and foaming is laminated on a base material, and then the first foaming The first foamable synthetic resin layer contains a finely powdered water-absorbing polymer and a foaming agent that creates countless interconnected microbubbles after heating and foaming, and is colored in the same color or a different color from the first foamable synthetic resin. at least 1
After forming two second foamable synthetic resins into an arbitrary pattern and further laminating a moisture-permeable resin film on the first and second foamable synthetic resin layers, the first and second foaming resin layers described above are formed. 1. A method for producing a dew-preventing foam decorative material, which comprises foaming and heating a synthetic resin.