JPH0570269A - Reversibly color-changeable tile - Google Patents

Abstract

PURPOSE:To provide a reversibly color-changeable tile capable of being used outdoors over a long period and excellent in weatherability and durability. CONSTITUTION:A dyestuff 4 with the color reversibly changed in a definite temp. range is interposed between a substrate 5 and a transparent protective plate 2 to form the reversibly color-changeable tile. In this case, a protective thin film 3 capable of selectively transmitting the light over a range of wave length not deteriorating the dyestuff is provided between the dyestuff 4 and the protective plate 2. Consequently, the dyestuff is not deteriorated by the light through the intervention of the protective thin film 3, and a reversibly color-changeable tile 1 capable of being used outdoors over a long period is provided.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a reversible color-changing tile,
More specifically, the present invention relates to a tile material used for covering a road surface, a floor, a wall, etc., which has a decorative function of reversibly changing color due to temperature changes, and particularly to a tile material suitable for long-term outdoor use. ..

[0002]

2. Description of the Related Art Thermochromic dyes that exhibit different colors depending on temperature have been mainly used in industrial applications such as temperature-sensitive tapes and temperature-sensitive paints. This is because the conventional thermochromic dyes are mainly composed of an inorganic substance, have a relatively high color changing temperature range, and few of them can reversibly change color near room temperature.

However, in recent years, various thermochromic pigments have been developed which are mainly composed of organic substances and which reversibly change colors near room temperature and have a vivid coloration. These organic reversible thermochromic dyes are roughly classified into two types, one that uses the change in the molecular structure of liquid crystal with temperature and the other that uses the change in color due to the change in acid-base equilibrium with temperature. Both have included a dye in the microcapsule to protect it.

Conventionally, many life-related products using these dyes have been devised. For example, Japanese Patent Laid-Open No. 61-6303
Japanese Patent Application Laid-Open No. 61-18148 discloses a method for producing a thermoreversible color-changing artificial flower using a sheet colored with a reversible thermochromic dye.
Japanese Patent Laid-Open No. 1 discloses a method of manufacturing a stuffed toy with a cloth colored with a thermochromic pigment. In addition, JP-A-61-1
In Japanese Patent No. 96988, there is disclosed a doll whose hair is composed of fibers colored with a thermochromic pigment, which are disclosed in Japanese Patent Laid-Open Nos. 61-249786, 61-249787 and 61-
Japanese Patent No. 281215 proposes an image display body in which a reversible thermochromic dye and a variable pixel portion formed by ordinary ink printing are combined. Further, Japanese Utility Model Laid-Open No. 62-51149 discloses glassware patterned with a reversible thermochromic dye, and Japanese Utility Model Laid-Open No. 1-121474 discloses a cup with a pattern coated with the reversible thermochromic dye. Has been done.

On the other hand, some building materials having a decorative function using a reversible thermochromic pigment have been devised. For example,
Japanese Unexamined Patent Publication No. 60-200226 discloses an invention relating to a device and a structure in which a product surface is coated with a liquid crystal composition whose color is changed by a temperature change, and a transparent or semitransparent coating agent is coated on the outside thereof. Among them, a tile material coated with a thermochromic liquid crystal is described as an example.

Further, Japanese Utility Model Publication No. 62-120637 discloses a device relating to a tile material coated with a cholesteric liquid crystal exhibiting a thermochromic property. Further, Japanese Utility Model Laid-Open No. 56-174635 discloses a liquid crystal color changing tile in which a protective film is formed on the surface of a tile coated with a thermochromic liquid crystal by using an ultraviolet curable resin.

[0007]

By the way, in recent years, not only the living environment but also the general comfort of the living environment including work and play environment has become more important. As a part of this, not only the exterior of the building has a function, but also the user's pleasant decoration is required. If a building material coated with a reversible thermochromic pigment is used for the exterior of a building, its appearance can be changed according to changes in the climate, and a visually unique effect can be obtained. In particular, reversible thermochromic pigments containing organic matter as the main component have a color-changing temperature range within a temperature fluctuation range of about one year, and it is expected that detailed visual effects will be obtained according to changes in the four seasons. To be done.

However, the weather resistance of the reversible thermochromic pigment containing an organic substance as a main component is far inferior to that of a general paint. The first reason is that reversible thermochromic pigments containing these organic substances as the main component are extremely vulnerable to the irradiation of ultraviolet rays and some short-wavelength visible light, and are exposed to ultraviolet rays in the sunlight for a short period of time. There is a deterioration between. Secondly, the pigment or the microcapsule encapsulating the pigment is destroyed by the acid or alkali in rainwater. By the way,
Most of the reversible thermochromic pigments containing commercially available organic materials as a main component warn that the color tone and the color changing temperature change when used outdoors in the instruction manual.

For this reason, many of the life-related articles cited in the above-mentioned conventional techniques are premised on being mainly used indoors. Also, JP-A-60-200226, JP-A-56-174635, JP-A-62-1206.
In any of the inventions of Japanese Patent No. 37, no special measure for improving weather resistance is taken, and it must be said that it is practically difficult to use these inventions outdoors.

The poor weather resistance of such a reversible thermochromic dye is due to the property itself of the dye that its structure changes with temperature changes near room temperature, and the weather resistance of the dye itself is not dramatically improved. Hard to hope for. Therefore, it is necessary to devise a mechanism for protecting the reversible thermochromic dye from ultraviolet rays, some short-wavelength visible rays, and rainwater.

The present invention has been made in view of the above conventional circumstances, and an object of the present invention is to provide a reversible color-changing tile excellent in weather resistance and durability, which can be used outdoors for a long period of time. ..

[0012]

The reversible color-changing tile according to claim 1 is a protective plate that is transparent to at least a part of visible light (hereinafter sometimes simply referred to as "protective plate" or "transparent protective plate"). In the reversible color-changing tile formed by interposing a pigment that reversibly discolors in a certain temperature range (hereinafter sometimes referred to as "reversible thermochromic pigment") or a thin film containing the pigment, A thin film that selectively transmits only light in a wavelength range that does not cause deterioration of the dye between the protective plate and the dye or the thin film containing the dye that reversibly changes color in the certain temperature range (hereinafter It may be referred to as a "protective thin film").

A reversible color-changing tile according to a second aspect is the reversible color-changing tile according to the first aspect, in which the peripheral portion of the substrate and the protective plate is:
It is characterized in that an adhesive margin for directly adhering both plates is provided.

A reversible color-changing tile according to a third aspect of the present invention comprises a substrate and a protective plate transparent to at least a part of visible light,
In a reversible color-changing tile formed by interposing a dye or a thin film containing the dye that reversibly changes color in a certain temperature range, the protective plate does not cause deterioration of the dye that reversibly changes color in the certain temperature range. A material that selectively transmits only light in the wavelength range (hereinafter sometimes referred to as "protective material").
It is characterized by including.

A reversible color-changing tile according to a fourth aspect is the reversible color-changing tile according to the third aspect, in which the peripheral portion of the substrate and the protective plate is:
It is characterized in that an adhesive margin for directly adhering both plates is provided.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a perspective view of one embodiment of the reversible color-changing tile of the present invention, and FIG. 2 is a sectional perspective view showing another embodiment. In FIG. 1 and FIG. 2, members having the same function are denoted by the same reference numerals, 1 and 1A are reversible color-changing tiles, 2 is a transparent protective plate, 3 is a protective thin film, and 4 is a reversible thermochromic pigment. Reference numeral 5 indicates a substrate, and 6 indicates an adhesive.

The reversible color-changing tile 1 shown in FIG. 1 comprises a substrate 5, a reversible thermochromic dye 4, a protective thin film 3 and a transparent protective plate 2.
The protective thin film 3 prevents the reversible thermochromic dye 4 from being deteriorated by light by sequentially laminating. The reversible color-changing tile 1A shown in FIG. 2 has a laminated structure similar to that of the reversible color-changing tile 1 of FIG. 1, and is provided with an adhesive margin on the peripheral portion of the substrate 5 and the peripheral portion of the transparent protective plate 2. The plates 5 and 2 are directly adhered to each other with an adhesive 6 to completely seal the inside to shield the reversible thermochromic dye 4 from the outside air, thereby preventing the reversible thermochromic dye 4 from being deteriorated by light. At the same time, deterioration due to air, moisture, or other external factors is prevented.

The constituent materials of the reversible color-changing tile of the present invention will be described below.

As the substrate used in the reversible color-changing tile of the present invention, any material generally used as a tile substrate may be used. On the other hand, the protective plate needs to be transparent in at least a part of the visible light wavelength range, but does not necessarily have to be transparent in the entire visible light range. Further, that the protective plate itself has a function of absorbing or reflecting ultraviolet rays,
It is preferable in terms of the protective effect of the dye, but is not an essential requirement.
Examples of the protective plate, various inorganic glass plate or acrylic resin, polystyrene resin, polycarbonate resin, a thick plate of a transparent polymer such as polyester resin,
It is not necessarily limited to these.

The reversible thermochromic dye used in the reversible color-changing tile of the present invention has a color changing temperature in the range of -20 ° C to 40 ° C, more preferably 0 ° C to 30 ° C, and reversibly changes the color. Any material may be used as long as it is a dye, but generally, a reversible thermochromic dye mainly containing an organic substance corresponds to this. As such reversible thermochromic dyes, those having various discoloration temperatures and colors are generally sold, and these can be used for producing the product of the present invention. The reversible thermochromic dye may be applied to either the protective thin film side or the substrate side, or the one applied in advance on the protective thin film may be sandwiched between the transparent protective plate and the substrate.

The protective thin film, which is provided between the transparent protective plate and the reversible thermochromic dye and selectively transmits only light in a wavelength range that does not cause deterioration of the dye, is an important element constituting the present invention. is there. The protective thin film can be formed using either an inorganic material or an organic material. Examples of inorganic materials include zinc oxide (ZnO), titanium oxide (TiO ₂ ), silicon carbide (SiC), cadmium sulfide (CdS), and triiron tetraoxide (Fe ₃ O ₄ ). Alternatively, a liquid dispersed in an inorganic binder is applied to the surface of the protective plate to have a thickness of 0.1 to 10 μm, preferably 1 to 5 μm.
It can be a protective thin film to some extent. If the thickness is this, the protective thin film has sufficient transparency for practical use.
It may be heat-treated at ℃. The protective thin film of the inorganic material can also be prepared by a method generally called a sol-gel method. Also in this case, the transparency of the protective thin film can be improved by performing heat treatment. When heat treatment is required, it is necessary to use an inorganic glass plate as the protective plate, but when heat treatment is not performed and only coating is performed, the inorganic glass plate is not necessarily required. On the other hand, examples of organic materials suitable for the protective thin film include organic UV absorbers such as para-aminobenzoic acid, ethyl para-aminobenzoate, isobutyl para-aminobenzoate and phenyl salicylate. All of these are widely used as additives for improving the weather resistance of polymer materials. By mixing these organic UV absorbers with a transparent polymer material such as acrylic resin and applying it to the surface of the protective plate, or by molding the resin into a thin film and inserting it between the protective plate and the pigment. A protective thin film layer can be formed. Alternatively, when the protective plate is made of a transparent polymer material such as acrylic resin, polystyrene resin, polycarbonate resin, polyester resin, etc., the organic UV absorber is directly mixed with the resin used as the material of the protective plate for protection. The plate itself may be provided with the function of the protective thin film, and the protective thin film may not be separately provided.

As an adhesive used for firmly adhering both substrates to each other by providing an adhesive margin on the periphery of the substrate and the protective plate, an adhesive having a strong adhesive property and a high sealing property such as an epoxy adhesive. Agents and the like are preferred.

[0024]

In the reversible color-changing tile of the present invention, the substrate imparts the mechanical strength required for the tile material, the reversible thermochromic pigment imparts a color effect, and the protective plate mechanically protects the reversible thermochromic pigment. .. Then, the protective thin film or the protective material chemically protects the dye. In particular, by using a protective thin film or a protective material, it is possible to completely block ultraviolet rays and a part of short-wavelength visible rays that cause the functional deterioration of the reversible thermochromic dye.

The wavelength range of light blocked by the protective thin film can be arbitrarily set depending on the material of the thin film. For example, ZnO
Cuts off only ultraviolet rays having a wavelength of 380 nm or less and allows most of visible light to pass therethrough, so that this can be protected without impairing the color of the dye. Since CdS absorbs a part of blue light, it exhibits a little yellow color, but is suitable as a protective thin film when the dye is deteriorated by blue light.

Further, by providing an adhesive margin around the protective plate and the substrate, firmly adhering the protective plate and the substrate, and sealing the reversible thermochromic dye to completely shield it from the outside air, the reversible thermal discoloration is obtained. The dye is fully protected from air, water, such as rainwater and acids, alkalis and other chemically active species contained in rainwater. That is, these acids, alkalis, and other chemically active species destroy the dye or the microcapsules that carry the dye, impairing the color and discoloration properties of the dye. Further, microcapsules are generally vulnerable to organic solvents, but by encapsulating the microcapsules, damage by organic solvents can be avoided.

[0027]

EXAMPLES The effects of the present invention will be described more specifically with reference to the following examples. Example 1 A reversible color change tile shown in FIG. 1 was prepared. That is, thickness 1
A glass protective plate having a thickness of 2 mm is coated with a solution in which fine particles of zinc oxide are dispersed in an organic binder and dried to have a thickness of 2 μm.
A protective thin film was prepared. The thin films coated with two types of commercially available reversible thermochromic pigments shown in Table 1 were sandwiched between a substrate of unglazed tile and a protective plate with a protective film layer to prepare samples A and B, respectively. For comparison, similar samples C and D were prepared using a protective plate without a protective thin film, and the samples A to D were irradiated with ultraviolet rays having a peak wavelength of 365 nm. The intensity of ultraviolet rays was 12 mW / cm ² on the sample surface. This intensity corresponds to about 5 times the intensity of ultraviolet rays of the same wavelength contained in sunlight at midday and noon.

Table 1 shows the results of the color change of the reversible thermochromic dye measured with a colorimeter. As is clear from Table 1, the dyes of Samples C and D without the protective thin film completely faded after a little over 200 hours, while the dyes of Samples A and B with the protective thin film almost changed even after 2000 hours. I didn't.

[0029]

[Table 1]

Example 2 A reversible color change tile shown in FIG. 2 was prepared.

A solution of titanium oxide fine particles (anatase) dispersed in an organic binder was applied to a glass protective plate having a thickness of 1 mm and dried to form a protective thin film having a thickness of 2 μm. Samples E and F were prepared by sandwiching a thin film coated with two types of commercially available reversible thermochromic pigments shown in Table 2 between a substrate of unglazed tile and a protective plate with a protective film layer and adhering and sealing the periphery with an epoxy resin. .. For reference, Samples G and H which were made of the same material and whose periphery was not adhered were prepared, and Samples E to H were fixed outdoors at a south-facing elevation angle of 45 degrees. The experiment started in April and continued until the end of July.

Table 2 shows the results of the color change of the reversible thermochromic dye measured with a colorimeter. As is clear from Table 2, the dyes of Samples G and H whose periphery was not sealed showed fading at the end of June, but the dyes of Samples E and F which were sealed were hardly changed until the end of the experiment.

[0033]

[Table 2]

[0034]

As described in detail above, the reversible color-changing tile of the present invention has the function of naturally changing its color and design in response to changes in temperature by using a reversible thermochromic pigment. If such a tile material is used for the decoration of the wall surface of a structure, etc., the appearance will be changed according to the change of the climate and the change of the four seasons to give the user a fresh impression and a sense of the season. The surrounding environment can be improved.

Therefore, according to the reversible color-changing tile of the present invention, the reversible thermochromic pigment sunlight can be obtained by using a protective thin film or a protective material that selectively absorbs ultraviolet rays and some short-wavelength visible rays. It is possible to use it outdoors for a long period of time by preventing its deterioration.

Particularly, according to the reversible color change tile of claim 2,
The weather resistance was further improved by sealing the reversible thermochromic dye and completely shielding it from the outside air.

The tile material of the present invention has a laminated structure in which each layer has a different function, and the most suitable material for each function can be selected from commercially available materials and combined, and has excellent mechanical strength and color. It has become possible to inexpensively manufacture products with effects, durability, and weather resistance.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a reversible color-changing tile of the present invention.

FIG. 2 is a sectional perspective view showing another embodiment of the reversible color-changing tile of the present invention.

[Explanation of symbols]

 1,1A Reversible color change tile 2 Transparent protective plate 3 Protective thin film 4 Reversible thermochromic dye 5 Substrate 6 Adhesive

Claims (4)

[Claims] 1. A reversible device comprising a substrate and a protective plate transparent to at least a part of visible light, and a dye or a thin film containing the dye which reversibly changes color in a certain temperature range. In the color-changing tile, between the dye or the thin film containing the dye that reversibly changes color in the certain temperature range and the protective plate, only light in a wavelength range that does not cause deterioration of the dye is selectively transmitted. A reversible color-changing tile characterized by having a thin film. 2. A peripheral portion of the substrate and the protective plate is provided with an adhesive margin for directly adhering the both plates.
The reversible color-changing tile described in. 3. A reversible device comprising a substrate and a protective plate transparent to at least a part of visible light, and a dye or a thin film containing the dye which reversibly changes color in a certain temperature range. In the color-changing tile, the protective plate includes a material that selectively transmits only light in a wavelength range that does not cause deterioration of a pigment that reversibly changes color in the certain temperature range. 4. A bonding margin for directly bonding the two plates is provided on the periphery of the substrate and the protection plate.
The reversible color-changing tile described in.