JP2000221885A - Reversible thermochromic display - Google Patents

Abstract

(57) [Summary] [Problem] An aspect (1) exhibited at an arbitrary temperature in a normal temperature range is:
By applying heat or cold heat, it can be changed to the appearance (2) or the appearance (3) at the same site and can return to the original appearance (1) slowly and spontaneously. Provided is a reversible thermochromic display material embodied as a form of a satisfying toy or the like. SOLUTION: A first reversible thermochromic layer 3 and a second reversible thermochromic layer 4 having different visual densities at the time of color development are superimposed on the same portion of the surface of a support 2 having specified thermal conductivity or heat capacity. It is formed by printing, and changes the appearance (1) to the appearance (2) or the appearance (3) by applying heat or cold in the temperature range of the living environment. Then, it is configured to slowly return to the original aspect (1) naturally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a reversible thermochromic display. More specifically, the aspect (1) exhibited in the normal temperature range is alternately changed to the aspect (2) or the aspect (3) at the same site by applying heat or cooling means in the living temperature range near the normal temperature range. After the heat or cold required for the change has been removed, the changed aspect (2) or (3) is allowed to return to the original aspect (1) slowly and spontaneously, and the state of the aspect change is changed for an appropriate time. And a reversible thermochromic display configured to be visible.

[0002]

2. Description of the Related Art Conventionally, a reversible thermochromic display, which makes an invisible image visible at room temperature by developing and erasing a reversible thermochromic layer due to temperature change, has been used for dolls, various figurative toys, picture books and labels. And the like, and has been put to practical use in various fields as forms of sheet-like printed matter, beverage containers, clothing, and the like, and many proposals have been disclosed. As the above-mentioned proposal, one or more layers of a reversible thermochromic image are overprinted on a non-thermochromic image (July 4-14).
787, Japanese Utility Model Publication No. 3-3429) and a quasi-reversible thermochromic image (non-thermochromic image) showing a large hysteresis width with respect to temperature-color density, discoloring, and removing heat or cold required for the change. Even after that, an example of overprinting (an image formed of a color-storing thermochromic material having a function of storing colors before and after a change in a specific temperature range) (Japanese Utility Model Publication No. 5-16597) is exemplified.

[0003]

DISCLOSURE OF THE INVENTION The present inventors have further pursued the discoloration effect of this type of thermochromic display, and the aspect (1) exhibited in the normal temperature range is in the living temperature range near the normal temperature range. By the application of heat or cooling means, it is possible to easily change the appearance (2) or the appearance (3) in the same part in a reciprocal and reversible manner, and after removing the heat or cold required for the discoloration, The toy is configured to slowly return to the aspect (1) naturally, to enhance the discoloration effect by visually observing the transition state of the aspect change, and to further exhibit a unique color effect such as a pastel tone. , Decorativeness, unexpectedness and design effects, and is embodied in the form of figurative toys, beverage containers, cards, clothing, other small items requiring decoration or design effects, and miscellaneous goods To provide a reversible thermochromic display It is.

[0004]

The present invention will be described with reference to the drawings (FIGS. 1 to 4). According to the present invention, the aspect (1) exhibited in the normal temperature range is changed to the aspect (2) or the aspect (3) by applying heat or cold at the same site, and spontaneously returns to the original aspect (1). A thermochromic display body having a thermal conductivity in the range of 0.02 to 160 Kcal / m · hr · ° C. and / or
Alternatively, at least two layers of the reversible thermochromic layer are laminated on the same portion of the support having a heat capacity in the range of 0.2 to 0.8 cal / g · ° C., and each of the layers has a color changing temperature and a color changing temperature. A reversible thermochromic pigment of a type that has a different color or color density, develops a color on a low temperature side below the discoloration temperature, and decolors on a high temperature side above the discoloration temperature is fixed in a dispersed state in a binder resin. The reversible thermochromic layer has a visual density at the time of color development higher than that of the first reversible thermochromic layer, and a non-thermochromic colorant is blended in the first reversible thermochromic layer and / or the lower layer. The aspect (1) is in a normal temperature range (15 ° C. to 30 ° C.).
C), the first reversible thermochromic layer is in a color-developing state and the second reversible thermochromic layer is in a decolored state at an arbitrary temperature of (° C.). On the higher temperature side, the first reversible thermochromic layer is in a decolored state, and the color provided by the non-thermochromic coloring agent in the layer and / or the lower non-thermochromic coloring layer is visible. And the aspect (3) is that at a temperature lower than the normal temperature range,
The second reversible thermochromic layer is in a color-developing state and is visible beyond the visual sense of the first reversible thermochromic layer, and the aspect (2) or (3) is heat or cold required for the change. Is required, a reversible thermochromic display which is configured to be able to slowly return to the original aspect (1) naturally so that the state of the aspect change can be visually recognized in the normal temperature range. Further, the reversible thermochromic pigment has a hysteresis width (ΔH) in the range of 3 to 10 ° C. with respect to the temperature-color density curve, and further, the first reversible thermochromic curve in the temperature-color density curve. The difference between the complete color development temperature (t ₁ ) of the reversible thermochromic pigment in the color change layer and the complete decolorization temperature (T ₄ ) of the reversible thermochromic pigment in the second reversible thermochromic layer is at least 1 ° C. In addition, the visual density is specified using the lightness value as a guide, and the lightness value at the time of color development is such that the first reversible thermochromic layer has a lower relationship than the second reversible thermochromic layer. The non-thermochromic colorant in the first reversible thermochromic layer is a white pigment, and is blended in a dispersed state in the layer. A plurality of colored pigments including are blended,
Further, the application of heat may be at any temperature in the range of 30 ° C. to 60 ° C., and the application of cold may be at any temperature in the range of 0 ° C. to 18 ° C., or even toy or decorative elements. And that the toy element is a doll toy.

The support 2 satisfying the physical property values in the above specific range,
And by applying a reversible thermochromic pigment having a hysteresis width (ΔH) within an appropriate range, it is possible to appropriately delay the response time due to the application of heat or cold, and to bring out the expected appearance, The changed aspect can be slowly returned to the original aspect (1) exhibited in the normal temperature range, and the visual effect can be enhanced. Examples of the support 2 satisfying the above requirements include paper, synthetic paper, plastics, wood, rubber, artificial leather, cloth, glass, aluminum, and the like, and processed products thereof. Thermal conductivity is 160 Kcal / m · hr
・ Systems exceeding ° C (eg, copper, silver, etc.) or systems having a heat capacity of less than 0.2 cal / g · ° C (eg, steel, brass, etc.)
In the case of, the appearance (2) or the appearance (3) is rapidly developed in response to heat or cold, and the original appearance is quickly returned when the heat or cold required for the change is removed. In a decorative field or an element intended for a design effect, the aspect change is instantaneous, and the visibility of the discoloration effect is poor. On the other hand, the thermal conductivity is 0.02 Kcal / m · hr ·
In a system having a temperature lower than 0 ° C. (for example, a mesh fabric) or a system having a heat capacity of more than 0.8 cal / g · ° C. (a porous wood or the like), the appearance change is too slow and the discoloration is not good. .

As the reversible thermochromic pigment, there are essential three types of known thermochromic materials, that is, an electron-donating color-forming organic compound, an electron-accepting compound, and an organic compound medium capable of reversibly generating a color reaction. Known pigment forms in which a thermochromic material containing components is encapsulated in microcapsules are effective (JP-B-51-44706, JP-B-51-44708, and JP-B-1) proposed by the present applicant. -293
No. 98, Japanese Unexamined Patent Publication No. 7-186540,
-17154, etc.). The particle size of the thermochromic pigment is in the range of 0.2 to 30 μm, preferably 1 to 30 μm.
m, more preferably in the range of 2 to 15 μm, are effective in terms of sensitivity of color change sensitivity, durability, workability and the like. The reversible thermochromic pigment has a temperature-color density curve (FIG. 4).
) Is about 3 to 10
Those in the range of ° C are effective. In a system of less than 3 ° C., the color development or decoloration state is rapidly developed by the application of cold heat or heat. However, when the cold heat or heat required for the discoloration is removed, the state immediately returns to the original state, and the visual effect of the appearance change is observed. Lack. On the other hand, thermochromic pigments having a ΔH exceeding 10 ° C. retain the color change state in the normal temperature range even after removing the cold or heat required for the color change, and newly add heat or cold heat. Unless is applied, it is impossible to spontaneously return to the original aspect (1) exhibited in the normal temperature range.

According to the present invention, a heat-decolorable first reversible thermochromic layer 3 and a second reversible thermochromic layer 4 are laminated on the same portion of a support 2, and the same portion at normal temperature range is formed. Since the aspect (1), the aspect (2), and the aspect (3) appear alternately, the second reversible thermochromic layer 4 is formed when the first reversible thermochromic layer 3 is colored. Must be set higher than visual density. Here, the aspect (3) may be set so that a colored state can be formed in two temperature ranges (for example, cold water or ice water) at 0 ° C. or higher. As a result, a room temperature state [modification (1)], a heated state [modification (2)], a cooling state [modification (3)], and a further cooling state [modification (31)] appear, and four changes in appearance are performed. Can be visualized. In addition, the visual density is a sensible shading to be perceived visually, and as one standard, the lightness value can be used as a scale. If the lightness value is relatively low, the visual density is relatively large. Suppose there is.

[0008] In the above structure, the first reversible thermochromic layer 3
Some blend non-thermochromic colorants,
When the reversible thermochromic pigment in the layer is in a color-developed state, that is, in a normal temperature range, a mixed color of the two is visually recognized. On the other hand, in a decolored state, that is, in a high temperature range, the non-thermochromic pigment in the layer is non-thermochromic. The color due to the colorant is visible. As the non-thermochromic colorant, conventionally known dyes, ultraviolet light-emitting dyes, general pigments, fluorescent pigments, luminous pigments, luminous pigments, metal powders, pearl pigments, extender pigments, photochromic colorants, fluorescent brighteners , Etc., as appropriate
Can be used. In a system using titanium white, a unique pastel tone caused by mixing with other non-thermochromic colorants blended in the same layer or by mixing with the color of the same layer when the thermochromic pigment develops. Colors can be revealed, toys,
A unique color effect can be achieved in the decoration, design and other fields. In a system in which titanium white or another colored pigment is blended, the color of the support 2 itself can be concealed, and the color of the blended pigment can be visualized regardless of the color of the support. In a system in which the non-thermochromic coloring agent is not blended in the first reversible thermochromic layer 3 and the non-thermochromic coloring layer is interposed between the first reversible thermochromic layer 3 and the support 2, Is in a decolored state, the non-thermochromic coloring layer can be visualized to give the same visual effect as described above. The reversible thermochromic layers 3, 4 include images of characters, symbols, designs, and the like.

The difference between the complete color development temperature (t ₁ ) of the thermochromic pigment in the first reversible thermochromic layer 3 and the complete decolorization temperature (T ₄ ) of the second reversible thermochromic layer 4 is at least 1 ° C. The above (preferably at least 3 ° C.) is effective for clearly distinguishing aspects (1) and (2) or aspects (1) and (3). Function. When the temperature is lower than 1 ° C., visual discrimination between the aspects is lacking. on the other hand,
In a system exceeding 15 ° C. (preferably 12 ° C. or less), the temperature difference between the heat or cold temperature required for discoloration and the room temperature range becomes large, and the simplicity of the discoloration operation tends to be impaired, which is not preferable.

In order to form the thermochromic layers 3 and 4 on the support 2, conventionally known coating methods, for example, printing means such as screen printing, offset printing, gravure printing, coater, tampo printing, transfer, brush, etc. Means such as coating and spray coating. Here, the support itself may also serve as the first reversible thermochromic layer 3. Further, when the support is made of a permeable material such as a cloth or paper, an undercoat layer of a resin thin film or the like is provided on the base in advance to prevent the penetration of the thermochromic ink during the formation of the thermochromic layer. It can deter and give the desired discoloration effect.

The content of the thermochromic pigment in the reversible thermochromic layers 3 and 4 is 5 to 80% by weight (preferably 10 to 6%).
0% by weight) is effective in view of the thermochromic effect. That is, if the content is less than 5% by weight, the color density is low and the color change cannot be clearly seen. On the other hand, if it exceeds 80% by weight, the residual color is visible, and it is difficult to see a clear decolored state. The thickness of the reversible thermochromic layers 3 and 4 is at least 0.5 μm or more, preferably 1 to 400 μm, more preferably 10 to 200 μm.
When the thickness is less than 0.5 μm, the sharpness of color change is lacking. On the other hand, when the thickness exceeds 400 μm, the aesthetic appearance tends to be impaired, which is not preferable.

The binder resin is preferably a transparent film-forming resin, and is exemplified below. Ionomer resin, isoprene-maleic anhydride copolymer resin, acrylonitrile-acrylic styrene copolymer resin, acrylonitrile-styrene copolymer resin, acrylonitrile-butadiene-styrene copolymer resin, acrylonitrile chlorinated polyethylene-styrene copolymer resin, ethylene-vinyl chloride Copolymer resin, ethylene-vinyl acetate copolymer resin, ethylene-vinyl acetate-vinyl chloride graft copolymer resin, vinylidene chloride resin, vinyl chloride resin, chlorinated vinyl chloride resin, vinyl chloride-vinylidene chloride copolymer resin, chlorinated polyethylene Resin, chlorinated polypropylene resin, polyamide resin, high density polyethylene resin, medium density polyethylene resin, linear low density polyethylene resin, polyethylene terephthalate resin, polybutylene terephthalate tree ,
Polycarbonate resin, polystyrene resin, high-impact polystyrene resin, polypropylene resin, polymethylstyrene resin, polyacrylate resin, polymethylmethacrylate resin, epoxy acrylate resin,
Alkyl phenol resin, rosin-modified phenol resin,
Rosin-modified alkyd resin, phenol-modified alkyd resin, epoxy-modified alkyd resin, styrene-modified alkyd resin, acryl-modified alkyd resin, amino alkyd resin, vinyl chloride-vinyl acetate resin, styrene-butadiene resin, epoxy resin, unsaturated polyester resin, polyurethane Resin, vinyl acetate emulsion resin, styrene-butadiene emulsion resin, acrylate emulsion resin, water-soluble phenol resin, water-soluble epoxy resin, water-soluble butadiene resin, cellulose acetate, cellulose nitrate, ethyl cellulose, etc. it can.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The reversible thermochromic display of the present invention may be in any form as long as it satisfies the above-mentioned constitutional requirements.

[0014]

EXAMPLES Examples will be described below, but the present invention is not limited to these. The parts in the examples are parts by weight.

Example 1 3-Cyclohexylamino-7-methylfluoran 3
Parts, bisphenol A5 parts, normal heptearate
Reversible heat consisting of 48 parts of chill and 2 parts of diheptadecyl ketone
Reversible thermochromic property in which discolorable material is encapsulated with epoxy resin film
Pigment (t₁ : About 24 ° C, t_Four : About 32 ° C, ΔH: about 6
° C, color change: orange ← → colorless) 1.3 parts and 3-dibutyl
3 parts of amino-6-methyl-7-anilinofluoran,
Sphenol A 6 parts, normal heptyl stearate 4
Reversible thermochromicity consisting of 8 parts and 2 parts of diheptadecyl ketone
Reversible thermochromic pigment encapsulating material with epoxy resin film
(T₁ : About 24 ° C, t_Four : About 32 ° C, ΔH: about 6 ° C, color
Change: black ← → colorless) 0.3 part with titanium white 1.4
Parts, xylene solution of acrylic resin (solid content 50%) 50
Parts, xylene 30 parts and methyl isobutyl ketone 30 parts
The coating liquid mixed and stirred in 20 parts of a vehicle consisting of
On the entire surface of the flesh-colored soft vinyl chloride resin molded product (support 2)
Spray painting with a spray gun, first reversible thermochromic layer
3 (lightness value at the time of coloring: 8.0) was formed. Then
1,2-benz-6-diethylaminofluoran 1.5
Part, 3-cyclohexylamino-7-methylfluoran
1.5 parts, 4,4 '-(2-ethylhexylidene) bis
Consists of 5 parts of phenol and 50 parts of decyl myristate
Reversible heat with reversible thermochromic material encapsulated in epoxy resin film
Discolorable pigment (T₁ : About 10 ° C, T _Four : About 22 ° C, ΔH:
Approx. 7 ° C, color change: red ← → colorless) 5 parts, acrylic resin key
50 parts silene solution (50% solids), 30 parts xylene
And 30 parts of methyl isobutyl ketone were stirred and mixed.
The liquid is sprayed on the reversible thermochromic layer 3 by a spray gun.
To the second reversible thermochromic layer 4 (coloring light
Degree value: 6.0) to form a reversible thermochromic display 1
Configured. The reversible thermochromic display 1 is at room temperature (about
25 ° C.), the skin color [modality (1)]
(Approx. 14 ° C) when cooled down, red dot pattern [like
Phase (3)] appears and is red when left at room temperature (about 25 ° C)
The dot pattern [Appearance (3)] disappears and the original skin color [Appearance]
(1)] slowly recovered. Meanwhile, heated with hot water (about 32 ° C)
Then, from the skin color state [Appearance (1)] to the white state [Appearance]
(2)], and when left at room temperature, the original appearance (1)
Slowly restored. The appearance change is reversibly repeated
Was done.

EXAMPLE 2 3 parts of 1,2-benz-6-diethylaminofluoran
A reversible thermochromic pigment (t ₁ : about 27) containing a reversible thermochromic material comprising 5 parts of 4,4′-decylidenebisphenol and 50 parts of stearyl caprate in an epoxy resin film.
° C, t ₄ : about 38 ° C, ΔH: about 7 ° C, color change: pink ← → colorless) 20 parts, titanium white 10 parts, pink aqueous processing pigment 0.05 parts, acrylate emulsion 7
Using a screen printing ink in which 0 parts, 1 part of a crosslinking agent, and 0.5 part of an antifoaming agent are dispersed, a heart pattern [first reversible] is formed on a deep pink polyester tricot fabric (support 2). Thermochromic layer 3 (lightness value at the time of coloring: 6.6)]
Was formed. Further, instead of the pink aqueous processing pigment of the screen printing ink, another heart pattern [first reversible thermochromic layer 3 ( Lightness value at the time of coloring: 6.6)] was formed. Then, 1 part of 3- (2-ethoxy-4-diethylaminophenyl) -3- (1-ethylindol-3-yl) -4-azaphthalide,
Bisphenol A 4 parts, myristyl alcohol 25 parts,
A reversible thermochromic pigment (T ₁₎ in which a reversible thermochromic material comprising 25 parts of decyl myristate is encapsulated with an epoxy resin film.
About 13 ° C., T ₄ : about 22 ° C., ΔH: about 4 ° C., color change: blue ← → colorless) 30 parts, acrylate resin emulsion 70 parts, cross-linking agent 1 part, defoamer 0.5 part Using the screen printing ink, a snow crystal pattern [second reversible thermochromic layer 4 (brightness value at the time of coloring: 4.
1)] to form a reversible thermochromic display 1. The reversible thermochromic display 1 is at room temperature (about 25
° C) shows a pink background [appearance (1)], about 18
When cooled to below ℃, a purple snow crystal pattern [appearance (3)] appears from above the pink ground, and when left at room temperature (about 25 ° C), the crystal pattern disappears slowly and the original [appearance (1) )]. On the other hand, when heated to about 38 ° C. or higher, the fabric becomes a pastel pink and pale yellow heart pattern [aspect (3)] from a pink background [aspect (1)]. (3) slowly returned to the original appearance (1). The appearance change was repeatedly and reversibly reproduced.

Example 3 3- (2-ethoxy-4-diethylaminophenyl)-
3- (1-ethyl-2-methylindol-3-yl)
Reversible thermochromic pigment (t) containing a reversible thermochromic material comprising 1 part of 4-azaphthalide, 5 parts of 4,4 '-(2-ethylhexylidene) bisphenol and 50 parts of myristyl myristate in an epoxy resin film (t ₁ : about 31 ° C., t ₄ :
About 41 ° C, ΔH: about 7 ° C, color change: blue ← → colorless) 10
Part, titanium white 5 parts, phthalocyanine blue pigment 0.01
Parts, vinyl chloride-vinyl acetate copolymer resin 20 parts, ketone-based medium-boiling solvent 40 parts, aromatic-based medium-boiling solvent 30 parts, and silicone-based antifoaming agent 0.5 part by a printing ink in a uniform dispersion state. Then, a character "A" [first reversible thermochromic layer 3 (brightness value at the time of coloring: 6.4)] was formed on a blue synthetic paper (support 2) by screen printing. Then, 3-dibutylamino-6-methyl-7-anilinofluoran 3
Thermoreversible pigment (T ₁ : about 10 ° C., T ₄ : about 22 parts), a reversible thermochromic material composed of 6 parts of bisphenol A and 50 parts of decyl myristate encapsulated in an epoxy resin film.
° C, ΔH: about 7 ° C, color change: black ← → colorless) 15 parts, vinyl chloride-vinyl acetate copolymer resin 20 parts, ketone-based medium boiling point solvent 40 parts, aromatic medium-based boiling point solvent 30 parts, silicone-based defoaming A number "1" [second reversible thermochromic layer 4 (brightness value at the time of coloring: 4.0)] is overprinted on the letter "A" with a screen printing ink in which 0.5 part of the agent is uniformly dispersed. did. Next, a toluene / ethyl acetate solution of acrylic resin (solid content: 40%) is applied on a 16 μm-thick polyester film, and the adhesive surface of the film from which the solvent has been evaporated is adhered to the printed surface of the printed matter, and then rolled. The laminate was pressed and laminated to obtain a thermochromic card (reversible thermochromic display 1). The reversible thermochromic display 1 exhibits a blue color [appearance (1)] at room temperature (about 25 ° C.), and when cooled to about 14 ° C. or less, a black numeral “1” appears on the blue surface.
[Appearance (3)] appeared, and when left at room temperature (approximately 25 ° C.), the above numbers gradually became invisible and returned to the original blue background [Appearance (1)]. On the other hand, when heated to about 41 ° C., a light blue letter “A” [appearance (2)] appears from above a blue background,
When left at room temperature (about 25 ° C.), the composition slowly returned to the original appearance (1). The appearance change was repeatedly and reversibly reproduced.

Example 4 3- (2-ethoxy-4-diethylaminophenyl)-
3- (1-ethyl-2-methylindol-3-yl)
Reversible thermochromic pigment (t) containing a reversible thermochromic material comprising 1 part of 4-azaphthalide, 5 parts of 4,4 '-(2-ethylhexylidene) bisphenol and 50 parts of stearyl caprate in an epoxy resin film (t ₁ : about 27 ° C., t ₄ : about 38 ° C., ΔH: about 7 ° C., color change: blue ← → colorless) 5 parts,
A coating solution obtained by stirring and dispersing 5 parts of a fluorescent yellow pigment, 30 parts of an acrylic resin toluene solution (solid content: 43%), 25 parts of xylene, and 25 parts of methyl isobutyl ketone was sprayed with a spray gun into a white ABS molded product (support 2). To obtain a first reversible thermochromic layer 3 (brightness value at the time of coloring: 5.0). Next, 0.1 part of a phthalocyanine-based blue pigment and 1 part of a yellow pigment
Parts, 2 parts of an alkyd-based resin (solid content 100%), 20 parts of an alkyd-based resin xylene solution (50% of solid content), 0.1 part of cobalt naphthenate, and 0.1 part of an antifoaming agent were mixed by stirring and mixing. A green star was printed on the coating by printing. Next, 3 parts of 3-dibutylamino-6-methyl-7-anilinofluoran, 6 parts of 4,4 ′-(2-ethylhexylidene) bisphenol, decyl myristate 45
Thermochromic pigment (T) in which a reversible thermochromic material consisting of 5 parts of butyl stearate is encapsulated with an epoxy resin film.
₁ : about 11 ° C., T ₄ : about 22 ° C., ΔH: about 10 ° C., color change: black ← → colorless) 5 parts, acrylic resin toluene solution (solid content 43%) 30 parts, xylene 25 parts, methyl isobutyl ketone Twenty-five parts were stirred and dispersed, and spray-coated in an elliptical shape on the green star print using a spray gun so that the star print could be concealed to form a second reversible thermochromic layer 4. Then, 30 parts of an acrylic resin toluene solution (solid content 43%), 1 part of an ultraviolet absorber, 25 parts of xylene,
25 parts of methyl isobutyl ketone were stirred and mixed, and spray-coated with a spray gun on the entire surface of the coated product to obtain a thermochromic ABS coated product (reversible thermochromic display 1).
The reversible thermochromic display 1 shows a green color [mode (1)] at room temperature, but when cooled to 14 ° C. or lower, a partially elliptical black pattern [mode (3)] appears. When the temperature was returned to room temperature, the black color disappeared and slowly returned to the original green color [appearance (1)] spontaneously. When the temperature is raised to 38 ° C. or more, a green star shape (mode (2)) is visually recognized on a yellow background, and when the temperature is returned to room temperature, the yellow background slowly returns to the original green (mode (1)). The green star has become difficult to see.

Example 5 3- (2-ethoxy-4-diethylaminophenyl)-
3- (1-ethyl-2-methylindol-3-yl)
Reversible thermochromic pigment (t ₁ : about 27 ° C.) containing a reversible thermochromic material comprising 1 part of 4-azaphthalide, 6 parts of 4,4′-decylidenebisphenol and 50 parts of stearyl caprate in an isocyanate resin film , T ₄ : about 38 ° C.,
ΔH: about 7 ° C., color change: 40 parts of blue →→ colorless), 5 parts of fluorescent pink pigment and 1000 parts of GP polystyrene resin were mixed, extruded at a cylinder temperature of 175 ° C. and a nozzle temperature of 170 ° C. A 2 mm flat plate was obtained. The flat plate functions as the support 2 on which the first reversible thermochromic layer 3 is integrally formed. Next, a reversible thermochromic pigment (T ₁ : about ₁ : ₁₎ in which a reversible thermochromic material comprising 2 parts of 1,2-benz-6-diethylaminofluorane, 6 parts of bisphenol A, and 50 parts of decyl myristate is encapsulated in an epoxy resin film. 10 ° C,
T ₄ : about 22 ° C, ΔH: about 7 ° C, color change: pink ← →
5 parts of colorless, toluene solution of acrylic resin (solid content 43
%) 25 parts of xylene and 25 parts of methyl isobutyl ketone were stirred and dispersed, spray-coated on the surface of the support 2 in a heart shape with a spray gun, and formed into a thermochromic molded article (reversible thermochromic display). A body 1) was obtained. The reversible thermochromic display 1 is a molded article of purple [modality (1)] at room temperature, but when cooled to 14 ° C. or lower, a pink heart pattern [modification (3)] appears, and when left naturally, The pink heart pattern disappeared, and gradually returned to the original purple color [aspect (1)]. When heated to 38 ° C. or higher, the purple molded product changed to a pink molded product (modality (3)), and slowly returned to the original purple color (modification (1)) when left naturally.

Example 6 3- (2-ethoxy-4-diethylaminophenyl)-
3- (1-ethyl-2-methylindol-3-yl)
A reversible thermochromic material comprising 1 part of 4-azaphthalide, 5 parts of 4,4 '-(2-ethylhexylidene) bisphenol, 48 parts of normal heptyl stearate and 2 parts of diheptadecyl ketone is encapsulated in an epoxy resin film. 4 parts of a reversible thermochromic pigment (t ₁ : about 24 ° C., t ₄ : about 32 ° C., ΔH: about 6 ° C., color change: blue ← → colorless), yellow pigment 0.1
Parts, titanium white 1 part, acrylic resin toluene solution (solid content 43%) 30 parts, xylene 25 parts, methyl isobutyl ketone 25 parts were stirred and dispersed, and white AB was sprayed with a spray gun.
It was spray-coated on an S resin molded product (support 2). Next, a reversible thermochromic material comprising 3 parts of 3-dibutylamino-6-methyl-7-anilinofluoran, 6 parts of bisphenol A, 25 parts of myristyl alcohol, and 25 parts of decyl myristate is encapsulated in an epoxy resin film. Thermochromic pigments (T ₁ : about 13 ° C., T ₄ : about 22 ° C., ΔH: about 4
5 ° C., color change: black ← → colorless) 5 parts, acrylic resin toluene solution (solid content 43%) 30 parts, xylene 25 parts, methyl isobutyl ketone 25 parts were stirred and dispersed, and sprayed on the above-mentioned coated material with a spray gun. Spray painted. Next, 1 part of pearl pigment and a toluene solution of acrylic resin (solid content 43
%) 30 parts, xylene 25%, and methyl isobutyl ketone 25 parts were stirred and dispersed, spray-coated in a star shape on the above-mentioned coated material with a spray gun, and then subjected to thermochromic coating (reversible thermochromic display). 1) was obtained. The reversible thermochromic display 1 is a green molded product [appearance (1)] at room temperature, but when cooled to a temperature of 18 ° C. or lower, a silver star pattern [appearance (3)] appears on a black background. Return to the original green color [Appearance (1)]
Slowly returned to nature. When the temperature was increased to 32 ° C. or more, the molded product changed from green to a pastel yellow [form (2)], and when the temperature was returned to room temperature, it gradually returned spontaneously to the original green form (1).

Example 7 3-Cyclohexylamino-7-methylfluoran 3
Part, bisphenol A 5 parts, normal heptyl stearate 48 parts, diheptadecyl ketone 2 parts reversible thermochromic material encapsulated by an epoxy resin film (t ₁ : about 24 ° C., t ₄ : about 32 ° C., ΔH: about 6
° C, color change: orange ← → colorless) 3.4 parts, phthalocyanine blue pigment 0.1 part, titanium white 1.5 parts, acrylic resin xylene solution (solid content 50%) 50 parts, xylene 30 parts and methyl isobutyl A coating liquid obtained by stirring and mixing 30 parts of ketone is applied to the upper part of the eyes of the face (support 2) of a doll modeled with flesh-colored soft vinyl chloride resin, and the eye shadow (first reversible thermochromic layer 3) is applied. Was formed. Next,
1.5 parts of Benz-6-diethylaminofluoran,
(2-ethoxy-4-diethylaminophenyl) -3-
(1-ethyl-2-methylindol-3-yl) -4
A reversible thermochromic pigment (T ₁ : about 10 ° C., containing a reversible thermochromic material comprising 0.8 parts of azaphthalide, 5 parts of 4,4′-decylidenebisphenol and 50 parts of decyl myristate) in an epoxy resin film; T ₄ : about 22 ° C., ΔH: about 7
5 ° C., color change: purple ← → colorless) 5 parts of an acrylic resin xylene solution (50% solids), 30 parts of xylene and 30 parts of methyl isobutyl ketone were stirred and mixed, and the coating liquid obtained was mixed with the above-mentioned coating part. Was spray-coated in the same pattern from above to obtain a thermochromic makeup doll (reversible thermochromic display 1). The thermochromic doll 1 is in a state without eyeshadow at room temperature (aspect (1)).
When cold water of 4 ° C. or less is applied, the state becomes purple with an eye shadow (aspect (3)). When left at room temperature, the purple eye shadow disappears, and the state without the original eye shadow (aspect (1)). Slowly returned to nature. 30 ° C
When the above warm water was applied, the state changed to a state in which the pastel blue eyeshadow was applied (aspect (3)), and when left at room temperature, it slowly returned spontaneously to the original aspect (1).

Example 8 3-Cyclohexylamino-7-methylfluoran 2
Part, 4,4 '-(2-ethylhexylidene) bisphenol, 5 parts of stearyl caprate, 50 parts of a reversible thermochromic material encapsulated in an epoxy resin film (t ₁ : about 27 ° C.) , T ₄ : about 38 ° C, ΔH: about 7 ° C,
Color change: orange ← → colorless) 3.5 parts, titanium white 1.5 parts,
Acrylic resin 50 parts of xylene solution (50% solids), 30 parts of xylene and 30 parts of methyl isobutyl ketone are stirred and mixed, and spray-painted on the entire buttocks (support 2) of a doll molded with flesh-colored soft vinyl chloride resin And the first
Was formed. Next, 1,2-Benz-
6 parts of 6-diethylaminofluoran, bisphenol A
5 parts, 25 parts of myristyl alcohol, 25 parts of decyl myristate, a reversible thermochromic pigment (T ₁ : about 13 ° C., T ₄ :
About 22 ° C, ΔH: about 4 ° C, color change: pink ← → colorless)
5 parts, acrylic resin xylene solution (solid content 50%) 50
Parts, 30 parts of xylene and 30 parts of methyl isobutyl ketone are stirred and mixed, spray-painted in a spot-like manner on the coating area, and a thermochromic therapeutic toy having a second reversible thermochromic layer 4 (reversible thermochromic discoloration) Indication 1) was obtained. The thermosensitive discoloration treatment toy 1 has no abnormality in the buttocks of the doll at room temperature.
When cooled to 8 ° C. or lower, red spots [appearance (2)] appeared, and when left at room temperature, the red spots gradually disappeared. 38 ° C
When the above-mentioned hot water was applied, the part became white, and it appeared as if a cream was applied [appearance (2)]. When left at room temperature, it gradually returned spontaneously from white to skin color [appearance (1)].

Example 9 A first reversible thermochromic layer 3 was formed on a flesh-colored soft vinyl chloride resin molded product (support 2) in the same manner as in Example 1, and then formed on the reversible thermochromic layer 3. , 3-cyclohexylamino-7-methylfluoran, 3 parts, bisphenol A5
, A reversible thermochromic pigment (T ₁ : about 14 ° C., T ₄ : about 21 parts), a reversible thermochromic material comprising an epoxy resin film containing 25 parts of myristyl alcohol, 10 parts of decyl myristate, and 15 parts of caprylic caprylate. 4 ° C., ΔH: about 4 ° C., color change: orange ← → colorless) 4 parts of an acrylic resin xylene solution (50% solid content), 30 parts of xylene and 30 parts of methyl isobutyl ketone were stirred and mixed. The coating liquid was spray-coated with a spray gun to form a second reversible thermochromic layer 4 (brightness value at the time of coloring: 7.0). Further, 3-cyclohexylamino-7-methylfluoran (3 parts), 4,4 ′-(2-ethylhexylidene)
A reversible thermochromic pigment (T ₁ : about 8) in which a reversible thermochromic material comprising 6 parts of bisphenol, 43 parts of decyl myristate and 7 parts of butyl stearate is encapsulated in an epoxy resin film.
° C, T ₄ : about 21 ° C, ΔH: about 10 ° C, color change: orange ←
(→ colorless) 1.0 part, 3-dibutylamino-6-methyl-7-anilinofluoran 3 parts, 4,4 ^, -(2-ethylhexylidene) bisphenol 6 parts, decyl myristate 43 parts, A reversible thermochromic pigment containing 7 parts of butyl stearate in an epoxy resin film (T ₁ : about 8 ° C., T ₄ : about 21 ° C., ΔH: about 10 ° C.,
Color change: 2 parts of black ← → colorless), 30 parts of acrylic resin xylene solution (solid content: 50%), 30 parts of xylene and 30 parts of methyl isobutyl ketone were stirred and mixed, and a spray gun was applied onto the thermochromic layer 4 with a spray gun. Similarly spray painting, another reversibly thermochromic layer ^4, (lightness values on coloration: 3.8)
To form a reversible thermochromic display 1. At room temperature (about 25 ° C.), the reversible thermochromic display 1
Skin color [modality (1)] and cold water (about 14-17
° C), an orange color [appearance (3)] appears on the flesh-colored surface, and an orange color [appearance (3)] when left at room temperature (about 25 ° C).
, And gradually returned spontaneously to the original skin color [appearance (1)]. Furthermore, when the cooling with ice water (about 11 ° C. or less), brown on the skin color surface: appearing [appearance ⁽³⁾ reversibly thermochromic layer 4 and ^4, but colored together, mixed colors] is, at room temperature (about 25 C.), the brown color [form (3 ^, )] disappeared and slowly returned to the original skin color [form (1)] without passing through the orange color [form (3)]. On the other hand, when heated with hot water (approximately 32 ° C.), it changes from a flesh-colored state [appearance (1)] to a white state [appearance (2)]. Slowly restored. The appearance change was reversibly repeated and reproduced.

[0024]

The reversible thermochromic display of the present invention is based on the appearance (1) at an arbitrary temperature in the normal temperature range, and becomes the appearance (2) by applying heat and the appearance (3) by applying cold. ) Can be changed in a discriminative manner.
At this time, the heat or cold heat can be easily achieved by, for example, human body heat, hot water, cold water, ice chips, cooling / heating equipment, environmental temperature change, and the like, which can be achieved by thermal means in a living temperature range near normal temperature. Also, it is safe without thermal danger at the time of discoloration play of infants and the like. Further, the aspect (2) or the aspect (3) is after the heat or cold required for the change is removed, and the manifested aspect slowly returns to the original aspect (1) spontaneously. It is possible to visually recognize the transition state of the appearance change without losing the state, and satisfy the taste of the discoloration and the visual effect. Further, in a system in which a white pigment is mixed in a dispersed state in the first reversible thermochromic layer, a pastel color can be visually recognized effectively by a change in appearance, and a unique color effect is provided. Since the reversible thermochromic display of the present invention has the above-mentioned characteristics, it can be applied and developed as makeup dolls, stuffed animals, other figurative toys, picture books, cards, artificial flowers, beverage containers, fabrics, and the like. It is.

[Brief description of the drawings]

FIG. 1 is an explanatory longitudinal sectional view showing an example of a reversible thermochromic display of the present invention.

FIG. 2 is an explanatory longitudinal sectional view of another example of the reversible thermochromic display of the present invention.

FIG. 3 is an explanatory longitudinal sectional view of another example of the reversible thermochromic display of the present invention.

FIG. 4 is a graph showing a temperature-color density curve relationship between thermochromic pigments in one embodiment of the present invention.

[Explanation of symbols]

1 thermochromic pigment in reversible thermochromic display 2 support 3 first reversibly thermochromic layer 4 second reversibly thermochromic layer t ₁ a first reversibly thermochromic layer complete coloring temperature t ₂ the first full of thermochromic pigments in thermochromic coloring initiation temperature t ₃ first decoloring starting temperature t ₄ the first reversible thermochromic layer of the thermochromic pigment in the reversibly thermochromic layer of the pigment in the reversibly thermochromic layer decoloring thermochromic at temperatures T ₁ second coloring initiation temperature T ₃ second reversibly thermochromic layer of the thermochromic pigment in the complete coloring temperature T ₂ second reversibly thermochromic layer of the thermochromic pigment in the reversibly thermochromic layer Decolorization start temperature of pigment T ₄ Complete decolorization temperature of thermochromic pigment in second reversible thermochromic layer ΔH ₁ Hysteresis width of thermochromic pigment in first reversible thermochromic layer ΔH ₂ Second reversible thermochromic Hysteresis width of thermochromic pigments in layers

Claims (9)

[Claims] 1. An aspect (1) exhibited in a normal temperature range is alternately changed to an aspect (2) or an aspect (3) at the same site by application of heat or cold, and spontaneously returns to the original aspect (1). Reversible thermochromic display having a thermal conductivity of 0.02 to 16
At least two reversible thermochromic layers are laminated on the same site of the support having a range of 0 Kcal / m · hr · ° C. and / or a heat capacity of 0.2 to 0.8 cal / g · ° C., Each of the layers has a color change temperature and a color or color density at the time of color change different from each other, a color is formed on a low temperature side lower than the color change temperature, and a color reversible thermochromic pigment of a type that is decolored on a high temperature side above the color change temperature is contained in the binder resin. The second reversible thermochromic layer has a higher visual density at the time of color development than the first reversible thermochromic layer, and the first reversible thermochromic layer and / or the lower layer Is blended with a non-thermochromic colorant,
In the aspect (1), the first reversible thermochromic layer is in a colored state and the second reversible thermochromic layer is at an arbitrary temperature in a normal temperature range (15 ° C. to 30 ° C.).
When the first reversible thermochromic layer is in a decolored state, the first reversible thermochromic layer is in a decolored state on a higher temperature side than a normal temperature range. The color provided by the non-thermochromic coloring agent and / or the lower non-thermochromic coloring layer is visually recognized, and the aspect (3) is a second reversible thermochromic coloration at a temperature lower than the normal temperature range. The layer is in a color-developing state and is visible beyond the visual sense of the first reversible thermochromic layer, wherein said aspect (2) or aspect (3) is after the heat or cold required for the change is removed A reversible thermochromic display which is configured to be able to slowly and spontaneously return to the original aspect (1) so that the state of the aspect change can be visually recognized in a normal temperature range. 2. The reversible thermochromic pigment has a hysteresis width (ΔH) of 3 to 10 ° C. with respect to a temperature-color density curve.
The reversible thermochromic display according to claim 1, wherein 3. In the temperature-color density curve, the complete color development temperature (t) of the reversible thermochromic pigment in the first reversible thermochromic layer
₁₎ and the second difference between the reversible thermochromic pigment complete decoloring temperature (T ₄₎ in the reversibly thermochromic layer, reversible thermochromic display of claim 1, wherein at least 1 ℃ or more. 4. The visual density according to claim 1, wherein the first reversible thermochromic layer is lower than the second reversible thermochromic layer in lightness at the time of color development. The reversible thermochromic display of any one of the above. 5. The non-thermochromic colorant contained in the first reversible thermochromic layer is a white pigment, and is blended in a dispersed state in the layer. Reversible thermochromic display. 6. The reversible thermochromic display according to claim 1, wherein a plurality of colored pigments containing titanium white are blended in the first reversible thermochromic layer. 7. The method of claim 1, wherein the application of heat is at any temperature in the range of 30 ° C. to 60 ° C. and the application of cold is at any temperature in the range of 0 ° C. to 18 ° C. Reversible thermochromic display. 8. The reversible thermochromic display according to claim 1, which is a toy element or a decorative element. 9. The reversible thermochromic display according to claim 8, wherein the toy element is a doll toy.