JPS63210147A - Production of nondripping expanded decorative material having ruggedness - Google Patents

Abstract

PURPOSE:To obtain the title decorative material excellent in a nondripping effect etc., by consecutively forming a synthetic resin layer containing a water- absorptive polymer and a blowing agent, a printed pattern of an ink containing an antifoamer and a moisture-permeable resin film on a base and expanding the synthetic resin layer by heating. CONSTITUTION:A synthetic resin layer 2 containing a finely powdered water- absorptive polymer (e.g., crosslinked polysodium acrylate) and a blowing agent which forms a number of open micropores after expansion by heating (e.g., azodicarbonamide) is formed on a base 1 such as paper or cloth. A desired pattern of a printing ink 3 containing an antifoamer (e.g., benzotriazole) is printed on the synthetic resin 2, and a moisture-permeable resin layer 5 is formed on this layer 2. The layer 2 is expanded by heating to obtain a nondripping expanded decorative material having ruggedness. It is also possible that the resin layer 5 is formed on the expanded layer after the resin layer 2 is expanded by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing a dew-preventing foam decorative material having an uneven pattern.

<Prior Art> There are three known methods for imparting dew condensation prevention effects to decorative materials using synthetic resins, which can be broadly classified into the following three methods. That is, one is to mix a water-absorbing polymer into the synthetic resin layer as disclosed in JP-A No. 56-3302, and the other is to mix a water-absorbing polymer into the synthetic resin layer as disclosed in JP-A-53-31772. The other method is to create a foam layer with countless interconnected microscopic cells, as shown in the Japanese Patent Publication No. 53-38.
As described in the No. 102 publication, the purpose is to provide moisture permeability by using an olefin-based microporous sheet.

<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 using a mechanical embossing device. The dew condensation prevention effect was significantly impaired, and the desired dew condensation prevention effect could not be achieved.

In the method of mixing water-absorbing polymers into the synthetic resin layer, the water-absorbing effect works only on the water-absorbing polymers exposed on the surface, but when mechanical embossing is applied to obtain a design for decorative materials, the surface The exposed area of the water-absorbing polymer that was previously exposed to water became narrower, or in extreme cases it was crushed, making it impossible to expect the original dew-preventing effect.

In addition, when mechanical embossing is applied to a foamed layer with countless interconnected microscopic bubbles to ensure the design, the foamed synthetic resin layer melts due to the heating during embossing and the interconnected microscopic bubbles disappear. In addition, the mechanical pressure during embossing crushed the communicating fine bubbles in the concave portions, and the desired dew condensation prevention effect could not be obtained.

In addition, even if the olefin-based microporous sheet is made moisture permeable, if it is mechanically embossed to ensure its design as an interior material, the heating during embossing will cause
There was a risk that the micropores in the sheet would melt and close, or the micropores would be crushed in the concave portions that were subjected to mechanical pressure during embossing, which would significantly impair the desired moisture permeability effect.

In addition, as a method for creating an uneven pattern that does not involve mechanical embossing, there is a method for producing an uneven pattern using an ink containing a foaming suppressant, as disclosed in Japanese Patent Publication No. 47-27794, which is a so-called chemical embossing method (chemical embossing method). known as the method of creation).

This chemical embossing method is often used for designs in which the concave portion and the image portion each have a large area.

For example, it was an excellent method for expressing designs such as tile and wood grain, but because the areas of concave and convex parts were large, it had the disadvantage that dew condensed quickly on the surface if the humidity in the dormitory was high. .

Therefore, the present invention skillfully combines the three advantages of a water-absorbing polymer, a foam layer with interconnected fine cells, and a moisture-permeable resin, and a chemical embossing method using an ink containing a foam inhibitor. The purpose of this invention is to provide an extremely excellent method for producing a foamed decorative material that prevents condensation.

<Means for Solving the Problems> The present invention provides a foaming agent that forms a micropowdered water-absorbing polymer and countless interconnected fine cells (open cells) after heating and foaming on a base material such as paper or cloth. A synthetic resin layer was formed, a desired pattern was printed on the synthetic resin layer with a printing ink containing a foaming inhibitor, and then a moisture-permeable resin film was further formed on the synthetic resin layer. The synthetic resin layer is then heated and foamed to reveal an uneven pattern, or the synthetic resin layer is heated and foamed to reveal an uneven pattern, and then a moisture permeable film is formed on the foamed layer. This is what I did.

More specifically, as the base material, any material such as paper, cloth, nonwoven fabric, aluminum hydroxide paper, synthetic paper, polysand paper, etc. can be used. These base materials are coated with a finely powdered water-absorbing polymer and a foaming agent that forms countless interconnected fine cells after foaming by heating and foaming using a known lamination method such as a coating method, a calendar method, a lamination method, or a rotary method. form a synthetic resin layer. As the resin used for this 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 preferably has the ability to absorb 50 times or more of its own weight of pure water. 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. Examples include polymers.

Commercially available products include, for example, Sumikagel-3P (Sumitomo Chemical), Zanwet IM-300 (Sanyo Chemical), Aqua Keep 4S (Steel Chemical Industries), and the like.

These water-absorbing polymers usually have a particle size of 350 to 0.1
Although it is a fine powder of approximately μ in size, an average particle size of 100 μ or less is preferable in consideration of dispersibility. The number of parts added is usually 2~
The amount is 40 parts, preferably around 5 to 15 parts.

The foaming agent added to the synthetic resin described above preferably has an open cell ratio of 70% or more after foaming in order to prevent 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, or by adjusting the foaming speed by selecting a stabilizer, or by adjusting the foaming heating temperature and foaming heating time. It can be achieved.

The aforementioned Japanese Patent Application Laid-Open No. 53-31772@ publication describes a combination of a foaming agent (UNIFORM AZ-F Oita Yakuhin) and a stabilizer (Stabilizer F Kyodo Yakuhin), a foaming agent (ONIFINE MO
There are examples of combinations of Oita Yakuhin) and optional stabilizers,
In the case of the present invention, it is also applicable even if the effect with the foaming suppressant described later is taken into consideration. In the case of vinyl chloride resin, common bovine bonamide is often used.

Foaming inhibitors have the effect of inhibiting the use of a foaming-promoting stabilizer that is mixed in advance into the foaming agent-containing synthetic resin layer.For example, foaming-promoting stabilizers include organic zinc compounds; Benzotriazole is an inhibitor of

Organozinc compounds work to lower the decomposition temperature of blowing agents,
The benzotriazole serves to substantially neutralize the effect of this organozinc compound and substantially increases the decomposition temperature of the blowing agent. Therefore, by adjusting the temperature and time of the foaming heat treatment, the areas to which the foaming inhibitor is applied and the areas to which it is not will become non-foaming areas and foaming areas, resulting in a difference in thickness. I will do it.

Furthermore, by delicately adjusting the temperature and time of the foaming heat treatment, the foaming agent in the area where the foaming inhibitor is printed can also be slightly foamed to ensure open air bubbles. Generally, in the case of heat-foamable vinyl chloride resin, the normal foaming heat treatment only decomposes 70-80% of the foaming agent contained, leaving 30-20% undecomposed and causing surface roughness due to over-foaming. is often prevented. Even when printing ink containing a foaming inhibitor is used, if the foaming heat treatment is applied to almost completely decompose the foaming agent in the synthetic resin layer that becomes the image area, the area to which the printing ink containing the foaming inhibitor has been applied will be It is also possible to decompose the foaming agent by 10 to 40% to form a slight foam layer, but in this case as well, depending on the design, it not only has sufficient commercial value, but also
This is extremely effective in achieving an excellent dew condensation prevention effect, which is the objective of the present invention.

There are many combinations of foam promoting stabilizers and foam inhibitors, as detailed in Japanese Patent Publication No. 47-27794, etc., and there are no disadvantages in combination with the foaming agent that forms open cells used in the present invention. does not occur.

Examples of moisture-permeable resins include urethane-based W10 emulsion resins, amino acid/methacrylic acid/urethane copolymers, and microporous sheets of the above-mentioned olefin resins. In order to not lose the performance of the moisture-permeable resin, and also to eliminate the seepage of cleaning waste water when wiping the foamed decorative material when it becomes dirty when used for wall coverings and furniture such as chairs. Preferred are amino acid/methacrylic acid/urethane copolymers that allow the passage of water only in the form of water vapor, but not in liquid form, although moisture permeable resins having properties similar to those described above may also be used.

To form a moisture-permeable resin film on the synthetic resin layer on the base material, either apply a moisture-permeable resin paint by a coating method, or
Alternatively, a pre-formed moisture permeable resin film may be laminated.

Furthermore, when forming a moisture-permeable resin film after the uneven pattern appears after foaming and heating, a surface treatment method using gravure printing can also be used. In this case, it is necessary to lower the viscosity of the moisture-permeable resin coating, so in order to form the desired film, it is necessary to perform overlapping gravure printing such as multicolor gravure printing. At this time, the moisture-permeable resin paint is printed on the foamed synthetic resin layer on which the uneven pattern has already been formed, but in the product of the present invention, there are countless open cells.
Even if the foamed convex portions are crushed by the pressure of the impression cylinder during gravure printing, they quickly recover, so there is no risk of damaging the steps of the concavo-convex pattern, and the amount of coating between the concave portions of the foamed synthetic resin layer and the layer portions is reduced. are approximately equal in amount, and have the practical advantage of retaining the function of the moisture-permeable resin coating.

<Effects of the Invention> According to the method of the present invention, water-absorbing polymers in the form of fine powder are almost uniformly mixed and scattered in the foamed synthetic resin layer having communicating fine cells, and moreover, the foamed synthetic resin layer has The surface is covered with a moisture permeable resin coating layer. Therefore, even if dew condensation is to form on the surface, the moisture will pass through the moisture-permeable resin coating layer and be actively absorbed by the continuous fine cells and water-absorbing polymer in the foamed synthetic resin layer, resulting in condensation. This prevents condensed water from adhering to the surface of the foam decorative material and flowing down.

When this foamed decorative material is used as wallpaper, it not only has the effect of preventing dew condensation, but if the room is extremely dry, the moisture (moisture) absorbed inside the foamed synthetic resin layer will be absorbed into the open fine cells. Due to the capillary phenomenon, it passes through the moisture-permeable resin coating layer and is gradually released into the indoor air, and also exerts a humidity control effect (humidity control effect).This humidity control effect is due to the indoor temperature and humidity and the foaming on the wall In addition to being influenced by the surface temperature of the decorative material, it is also affected by the total amount of moisture contained in the foamed synthetic resin layer, and in addition to this, the state of the presence of continuous fine bubbles (number and size of bubbles, etc.) It also depends on the thickness of the foamed synthetic resin layer.

If you want to actively control humidity in addition to preventing dew condensation, it is necessary to finely adjust the amount of foaming agent added and the foaming heat treatment. It is also extremely superior in that water droplets do not form on the surface when moisture is released due to the presence of .

In addition, we can delicately adjust the temperature and time of the foaming heat treatment,
By adjusting the thickness of the synthetic resin layer, the content of the foaming agent, and the concentration of the foaming inhibitor, the synthetic resin layer printed with the printing ink containing the foaming inhibitor can also be foamed to some extent and communicated with the concave portions. It is possible to make fine air bubbles appear, and if it is set in consideration of design, it has the advantage of ensuring the dew condensation prevention effect in the concave portions without significantly impairing the uneven steps.

According to the manufacturing method of the present invention, even when the synthetic resin layer portion on which the ink containing the foaming inhibitor is printed is subjected to foaming heat treatment so as not to foam at all, the surface of the concave portion that remains unfoamed (moisture permeable resin The water-absorbing polymer is exposed on the surface of the synthetic resin layer immediately below the coating.
Since no mechanical embossing is performed as in Publication No. 302, there is an advantage that the water-absorbing polymer exposed on the surface is not crushed. Similarly, JP-A-53-31
In the method disclosed in Japanese Patent No. 772, mechanical embossing is required to impart a design, and the heat and pressure during the mechanical embossing create a continuous gap in the foamed resin layer that becomes the concave part. The microbubbles disappear, and as a result, in the case of a design with a large area of the recessed part, no effect of preventing condensation in the recessed part could be expected at all, but according to the method of the present invention, Even if the design has a large area, there is no risk of impairing the dew condensation prevention effect of the recessed part, and especially if the synthetic resin layer printed with the printing ink containing a foaming inhibitor is slightly foamed as described above, It is possible to utilize not only the water-absorbing polymer exposed on the surface of the synthetic resin layer directly under the moisture-permeable resin film, but also the water-absorbing function of the water-absorbing polymer inside the synthetic resin layer, which significantly prevents condensation compared to conventional methods. It is extremely superior in that it can be effective.

Furthermore, according to the method of the present invention, the moisture-permeable resin film is not subjected to any pressure due to mechanical embossing, so it is also excellent in that there is no fear that condensed water will adhere to and run off even in the recessed portions.

<Example> Example 1゜A foamable vinyl chloride resin paste consisting of the following formulation was applied to aluminum hydroxide paper 1 using a doctor knife coating method.
．． It was coated to a thickness of 19 mm and dried for 1 minute at 130 to 140°C, which is lower than the decomposition temperature of the foaming agent, to form a semi-gelatinous material, thereby creating a synthetic resin layer 2 (Figure 1-A).

Resin: Polyvinyl chloride resin 100 parts Plasticizer: DOP 50 parts Stabilizer: A (Zn type) 1.0 parts Stabilizer: B (organozinc compound) 1.5 parts Foaming agent・・・
・ADCA system 5 parts filler...calcium carbonate 50 parts water-absorbing polymer...
Sumikagel 5P-5205 parts Pigment: Titanium white
15th part Next, a multicolor pattern was gravure printed using printing ink 3 containing 5 to 25% of the foaming inhibitor benzotriazole and ordinary printing ink 4 (first part).
-8 figure). For this printed pattern, a design was selected such that the ratio of the area of the area printed with the printing ink containing the foaming inhibitor to the area of the area not coated with the printing ink containing the foaming inhibitor was 50%.

Furthermore, a moisture-permeable resin coating consisting of an amino acid/methacrylic acid/urethane copolymer was coated on the printed synthetic resin layer using a gravure printing machine and dried, thereby forming a moisture-permeable resin layer 5. Figure 1-C).

Subsequently, this was introduced into a foaming heating furnace set at approximately 230°C and heated for 1 minute to cause foaming. When the printing ink containing the foaming inhibitor did not foam, the printed area formed a concave area, and the printing ink containing the foaming inhibitor did not form a concave area. The areas where there is no printing and the areas where nothing is printed expand and expand nearly five times the coating thickness to form convex areas, thereby obtaining an anti-condensation foam decorative agent having an uneven pattern that is in sync with the printed pattern. 〉.

This condensation-preventing foam decorative material having an uneven pattern had a ratio of 50% of the foamed convex portions to 50% of the unfoamed concave portions, and could be used as wallpaper.

Table 1 shows the test results of a comparison between the wallpaper of Example 1 and a conventional wallpaper having a similar uneven pattern.

Table 1 However, Comparative Example A: A water-absorbing polymer was mixed into the non-foamed synthetic resin layer and mechanically embossed to make the area ratio of the convex portions and concave portions approximately 50%. thing.

Comparative example day: A foamed synthetic resin layer having countless interconnected microscopic cells was mechanically embossed so that the area ratio of convex portions to concave portions was approximately 50%.

Comparative Example C: An olefin-based microporous sheet was laminated to a non-foamed synthetic resin layer and mechanically embossed so that the area ratio of convex portions to concave portions was approximately 50%.

In Example 1 described above, the moisture-permeable resin coating layer 5 was formed on the printed synthetic resin layer 2 before foaming and heating, but the same effect was ensured even if it was formed after foaming and heating.

Example 2 A foamable vinyl chloride resin paste having the following composition was coated on flame retardant paper 6 to a thickness of 0.19 mm by the doctor knife coating method, and then this was coated at a temperature lower than the decomposition temperature of the foaming agent.
It was dried at 0 to 140°C for 1 minute to form a semi-gelatinous material, thereby creating a synthetic resin layer 7 (Figure 2-A).

Resin: Polyvinyl chloride resin 100 parts Plasticizer: DOP 50 parts Stabilizer: A (Zn type) 1.0 parts Stabilizer: B (organozinc compound) 1.5 parts Foaming agent・・・
・ADCA system 7 parts Filler...Calcium carbonate 40 parts Water-absorbing polymer...
Sumikagel 5P-52010 parts Pigment: Titanium white
15 parts Next, a multicolor pattern is gravure printed using printing ink 8 containing 5 to 15% of the foaming inhibitor benzotriazole (Fig. 2-8). This printing pattern was selected so that the ratio of the area of the printed part of the printing ink containing the foaming inhibitor to the area of the unprinted part was approximately 50%.

Furthermore, a moisture-permeable resin coating consisting of an amino acid/methacrylic acid/urethane copolymer was applied and dried on the printed synthetic resin layer using a gravure printing machine to form a moisture-permeable resin layer 9 (second -0 figure).

Next, the flame-retardant paper 6 laminated with the unfoamed synthetic resin layer 7 that has been processed as described above is precisely and accurately heated to 190°C in the first chamber (furnace length: 5 m) and in the second chamber. is 21
0'C (furnace length -5m>, 3rd chamber is 240°C (furnace length...
・Introduced to a foaming heating furnace adjusted to 5 m) and heated for 1 minute 18
When heated for a second to cause foaming, the printing ink containing a foaming inhibitor formed a concave area that foamed at 2.5 times the coating thickness, and the non-printed area foamed at about 8 times the coating thickness. A condensation-preventing foam decorative material having a concave-convex pattern in sync with the printed pattern was obtained by forming convex portions (Figure 2-D).

This condensation-preventing foam decorative material with an uneven pattern has some foaming in the concave areas, and 1/4th of the number of connected microbubbles can be seen in the convex areas, and it can also be used as wallpaper in terms of design. It was something to do.

This Example 2 had a better dew condensation prevention effect than Example 1.

[Brief explanation of the drawing]

Figures 1-A to 1-D are for explaining embodiments of Example 1, and Figures 2-A to 2-D are for explaining embodiments of different stages of the manufacturing method of the present invention of Example 2. FIG. 1... Aluminum hydroxide (base material), 2... Synthetic resin layer containing a water-absorbing polymer and a heat foaming agent, 2'...
- Foamed synthetic resin layer, 3... Printing ink containing a foaming inhibitor, 4... Normal printing ink, 5... Moisture permeable resin layer, 6
...Flame retardant paper (substrate), 7.Synthetic resin layer containing a water-absorbing polymer and a heat foaming agent, 8.Printing ink containing a foaming inhibitor, 9.Moisture permeable resin layer, 7'...Convex portion foamed synthetic resin layer, 7''...Concave portion foamed synthetic resin layer.

Claims (1)

[Claims] 1. A synthetic resin layer containing a finely powdered water-absorbing polymer and a foaming agent that forms countless interconnected microbubbles after heating and foaming is formed on the base material, and a foaming inhibitor is contained on the synthetic resin layer. After printing a desired pattern with printing ink and further forming a moisture-permeable resin film on the synthetic resin layer, the synthetic resin layer is then heated and foamed, or after the synthetic resin layer is heated and foamed. A method for producing a condensation-preventing foam decorative material having an uneven pattern, the method comprising forming a moisture-permeable resin film on the foam layer.