JP2008207510A - Brilliant thermal-discoloring laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brilliant thermal discoloring laminate which presents a luster color with a high brilliance and presents a more variable discoloration by a discoloration of a reversibly thermal-discoloring layer. <P>SOLUTION: The brilliant thermal-discoloring laminate 1 comprises a laminate of: a reversibly thermal-discoloring layer 3 containing a thermal-discoloring composition consisting of an electron-donative coloration nature organic compound, an electron accepting compound, and an organic compound medium which makes both color reactions occur reversibly; and a brilliant layer 2 containing a brilliant pigment in which the surface of flat glass pieces is coated with silica dioxide, and further coated with titanium dioxide. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a bright tone thermochromic laminate. More specifically, the present invention relates to a bright-tone thermochromic laminate that exhibits a color tone that varies in color due to temperature changes.

Conventionally, a proposal by the present applicant has already been disclosed regarding a thermochromic laminate having a metallic luster tone (for example, Patent Document 1).
In the above proposal, the metallic luster pigment to be applied is a pigment obtained by coating the surface of natural mica or glass flakes with titanium oxide, and exhibits a metallic luster color of gold, silver or metallic depending on the coverage of titanium oxide. Therefore, it has a glittering appearance, and the reversible thermochromic layer changes color due to a temperature change, and a different aspect is made visible, so that it exhibits a unique color change compared to the color change of conventional thermochromic materials. It has applicability to various fields such as decoration and toys as well as the temperature indicating field.
Japanese Patent Laid-Open No. 5-13749

  The present inventor further pursued the visual effect of this kind of metallic luster thermochromic laminate, exhibiting a brighter brilliant color, and exhibiting a variety of color changes by changing the reversible thermochromic layer. It is an object of the present invention to provide a thermochromic laminate.

The bright-tone thermochromic laminate of the present invention comprises a thermochromic composition comprising an electron-donating color-forming organic compound, an electron-accepting compound, and an organic compound medium that reversibly causes a color reaction of both. It is a requirement that the reversible thermochromic layer and a bright layer containing a bright pigment coated with silicon dioxide on the surface of a flat glass piece and further coated with titanium dioxide are laminated.
Furthermore, a reversible thermochromic layer and a glitter layer are sequentially laminated on the support, a glitter layer and a reversible thermochromic layer are sequentially laminated on the transparent support, and the glitter layer and the reversible thermochromic layer. It is a requirement that a transparent support is interposed between the layers.

  According to the present invention, a bright color can be expressed, and a clear color change can be visualized with the color change of the reversible thermochromic layer, thereby imparting saliency, specificity, decoration, novelty, etc. It is possible to provide a bright and thermochromic laminate capable of being applied in various applications.

The laminate of the present invention is constituted by providing a bright layer on the upper layer, that is, the visible layer side, and a reversible thermochromic layer on the lower layer.
With the above-described configuration, the brilliant color due to the glitter pigment can be sufficiently expressed, and various color changes can be visually recognized in conjunction with the change in the appearance accompanying the color change of the reversible thermochromic layer provided in the lower layer.

The glitter pigment used in the present invention is a two-layer coating type pigment in which the surface of a flat glass piece is coated with silicon dioxide and further coated with titanium dioxide.
Since the silicon dioxide has higher hardness than glass and is excellent in acid resistance, even if the thickness of the glass piece serving as the core is reduced, it can be maintained in a state where it is difficult to break (specifically, a thickness of 1 μm or less). Therefore, the weight per reflection area can be reduced, and the light transmittance of the pigment can be improved.
Therefore, compared with the case of using a metallic luster pigment such as a conventional glass flake pigment (a pigment having the surface of the glass flake coated with titanium oxide), higher gloss is obtained when the same amount is added as the light transmission improves. And the dispersibility in the glitter layer is improved by reducing the weight of the pigment particles.

  As the luster pigment, those having an average particle diameter of 10 to 200 μm are suitable. When the particle diameter is larger than 200 μm, the surface of the glitter layer is rough and rough, and when it is smaller than 10 μm, it is difficult to give high luminance.

  Examples of the bright pigments include trade names “Miraval” manufactured by Merck & Co., Inc .: 5311 Scientific White, 5411 Magic White KU28, 5420 Magic Gold, 5421 Magic Copper, 5422 MagicL, 5423 MagicL, 5423 MagicL, 5423 5426 Magic Green and the like.

Using ink or paint in which the glitter pigment is dispersed in a vehicle, conventionally known methods such as screen printing, offset printing, gravure printing, coater, tampo printing, transfer printing means, brush coating, spray coating, etc. The glitter layer can be formed by means such as electrostatic coating, electrodeposition coating, flow coating, roller coating, and immersion coating.
Further, a molded body formed by blending the glitter pigment in a thermoplastic resin or a thermosetting resin may be used as the glitter layer.
Conventionally known metal luster pigments, pearl luster pigments, dyes, pigments, fluorescent pigments, phosphorescent pigments, and the like can also be used in combination.
Examples of the pearlescent pigments include natural mica, synthetic mica, glass flakes, pigments having a surface coated with a metal oxide such as titanium oxide, and cholesteric liquid crystal polymer pigments.

The reversible thermochromic layer contains a reversible thermochromic composition in the layer, and the composition is an electron donating color-forming organic compound, an electron-accepting compound, an organic that reversibly causes a color reaction. A composition containing three components of a compound medium is preferably used. Specific examples include reversible thermochromic compositions described in JP-B-51-44706 and JP-B-1-29398.
The composition discolors before and after a predetermined temperature (discoloration point), and only one specific state can exist in the normal temperature range among both states before and after the change. That is, the other state is maintained while the heat or cold necessary to develop the state is applied, but when the heat or cold is no longer applied, the state returns to the state exhibited in the normal temperature range, so-called, This is a type in which the temperature-color density due to temperature change shows a small hysteresis width (ΔH) and changes color.

  Further, as described in Japanese Patent Publication No. 4-17154 proposed by the present applicant, a thermosensitive color-changing color memory thermochromic composition that changes color while exhibiting a large hysteresis characteristic, that is, a color density due to a temperature change. The shape of the curve in which the change is plotted is a type in which the color changes following a path that differs greatly depending on whether the temperature is raised from the lower temperature side than the color change temperature range or when the temperature is lowered from the higher temperature side than the color change temperature range. Reversible heat having a feature that can store and retain a state changed at a temperature below the low temperature side color change point or above the high temperature side color change point in a normal temperature range between the low temperature side color change point and the high temperature side color change point. A color changing composition is also effective.

  Furthermore, as an electron-accepting compound proposed by the present applicant that develops color by heating from a decolored state as a heat-colorable composition, a specific compound having a linear or side chain alkyl group having 3 to 18 carbon atoms Examples include systems to which alkoxyphenol compounds are applied (Japanese Patent Laid-Open Nos. 11-129623 and 11-5973), and systems to which specific hydroxybenzoic acid esters are applied (Japanese Patent Laid-Open No. 2001-105732). . Furthermore, a system to which gallic acid ester or the like is applied (Japanese Patent Publication No. 51-44706) can be applied.

The reversible thermochromic composition described above is effective even when applied as it is, but the reversible thermochromic composition is maintained in the same composition even under various usage conditions, and can exhibit the same effects. It is preferable to use it in a microcapsule.
By encapsulating in the microcapsule, a chemically and physically stable microcapsule pigment can be constituted, and the particle diameter of 0.1 to 100 μm, preferably 0.1 to 30 μm, satisfies the practicality.
Microencapsulation includes conventionally known interfacial polymerization methods, in situ polymerization methods, in-liquid curing coating methods, phase separation methods from aqueous solutions, phase separation methods from organic solvents, melt dispersion cooling methods, air suspensions. There are a coating method, a spray drying method, and the like, which are appropriately selected according to the application. Further, a secondary resin film may be provided on the surface of the microcapsule according to the purpose to impart durability, or the surface characteristics may be modified for practical use.

A reversible thermochromic layer can be formed by a conventionally known method using the reversible thermochromic composition or ink or paint in which microcapsules containing the composition are dispersed in a vehicle.
Furthermore, you may use the molded object formed by blending the microcapsule pigment which included the said reversible thermochromic composition in a thermoplastic resin or a thermosetting resin as a reversible thermochromic layer.

  In the reversible thermochromic layer, an appropriate amount of a non-thermochromic dye / pigment can be mixed to reveal more various color changes.

A support is not particularly required when at least one of the bright layer and the reversible thermochromic layer is a molded body, but a support is required when each layer is formed from a liquid composition such as ink or paint.
The support is selected from materials such as paper, synthetic paper, metal, ceramics, stone, wood, glass, resin, and fabric, and the shape is not particularly limited.
When an opaque support is used, a reversible thermochromic layer and a glitter layer are sequentially laminated on the support. In this case, as described above, a laminated body having high brightness and luster can be obtained.
When a transparent support is used, a glitter layer and a reversible thermochromic layer can be sequentially laminated. In this case, when viewed from the support side, a laminated body having high brightness and luster as described above can be obtained. Further, when a transparent support is used, the transparent support can be interposed between the reversible thermochromic layer and the glitter layer.
Examples of the transparent support include glass and resin, and a resin molded body or a resin film is preferably used.
In addition, the said transparency may be translucent, colored transparent, and colored translucent besides colorless and transparent.

It is preferable to provide a protective layer on the uppermost layer of the laminate so as to improve durability and water resistance.
Furthermore, a light stabilizer layer can be appropriately provided between the uppermost layer of the above-described laminate or each layer. Specifically, the light stabilizer layer is selected from an ultraviolet absorber, an antioxidant, an anti-aging agent, a singlet oxygen quencher, a superoxide anion quencher, an ozone decolorant, a visible light absorber, and an infrared absorber. The light stabilizer is fixed in a dispersed state and can be formed according to the preparation of the reversible thermochromic layer or the glitter layer.
In addition, it is more preferable to provide a light stabilizer layer as the uppermost layer because the light resistance of the reversible thermochromic layer can be imparted in addition to durability and water resistance.

  The glittering thermochromic laminate 1 of the present invention is formed by laminating two layers of a glittering layer 2 and a reversible thermochromic layer 3, and at least one of the above layers has a thickness and strength as a support 4. If it does, the support body 4 is not required. In addition, when the material forming each layer is a liquid material such as a paint, the layers are appropriately coated on the support 4 as appropriate. Furthermore, when each layer is formed of a molded body, each layer is bonded to obtain a laminate.

  Examples are shown below. In addition, the part in an Example is a weight part.

Example 1 (see FIG. 1)
A luster pigment formed by coating the surface of a flat glass piece with silicon dioxide and further coating with titanium dioxide (Merck, trade name: Miraval 5411 Magic White KU28, particle size 20-200 μm), acrylic ester resin, Under the glitter layer 2 having a thickness of about 30 μm, 3 parts of 2-anilino-3-methyl-6-dibutylaminofluorane, 6 parts of 4,4 ′-(2-methyl-propylidene) bisphenol, neopentyl stearate 50 A thickness comprising a reversibly thermochromic microcapsule pigment having an average particle size of 8 μm obtained by encapsulating a thermochromic composition comprising a part of a compatible solution with an epoxy resin / amine curing agent interfacial polymerization method and an acrylate resin The reversible thermochromic layer 3 having a thickness of about 40 μm was laminated to obtain a bright tone thermochromic laminate 1.

  When the reversible thermochromic layer 3 was visually recognized from the side of the glitter layer 2 in a colored state (black) of 15 ° C. or less, the laminate 1 showed a bright metallic luster color. Further, when the reversible thermochromic layer 3 was decolored at 32 ° C. or higher, the chromatic color was not visible and the colorless laminate 1 was obtained. This aspect change could be repeated.

Example 2 (see FIG. 1)
A luster pigment formed by coating the surface of a flat glass piece with silicon dioxide and further coating with titanium dioxide (manufactured by Merck, trade name: Miraval 5422 Magic Red, particle size 20 to 200 μm), and an acrylate resin Under the glitter layer 2 having a thickness of about 30 μm, 1 part of 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide, 4, Average particle diameter obtained by encapsulating a thermochromic composition comprising 6 parts of 4 '-(2-methyl-propylidene) bisphenol and 50 parts of neopentyl stearate by an epoxy resin / amine curing agent interfacial polymerization method. A reversible thermochromic layer 3 having a thickness of about 40 μm composed of an 8 μm reversible thermochromic microcapsule pigment and an acrylate resin is laminated. To obtain a bright tone thermochromic laminate 1 Te.

  In the laminate 1, when the reversible thermochromic layer 3 was viewed from the bright layer 2 side in a colored state (blue) of 15 ° C. or less, a bright purple color was observed. Further, when the reversible thermochromic layer 3 was decolored at 32 ° C. or higher, the chromatic color was not visible and the colorless laminate 1 was obtained. This aspect change could be repeated.

Example 3 (see FIG. 2)
As support 4, on the upper layer of a white polyvinyl chloride film, 3 parts of 2-anilino-3-methyl-6-dibutylaminofluorane, 6 parts of 4,4 '-(2-methyl-propylidene) bisphenol, 25 parts of cetyl alcohol 40 parts of a reversibly thermochromic microcapsule pigment having an average particle size of 10 μm obtained by encapsulating a thermochromic composition comprising 25 parts of stearyl caprate with an epoxy resin / amine curing agent interfacial polymerization method, ethylene, -Reversible thermochromic layer 3 by screen printing using reversible thermochromic ink obtained by uniformly stirring and dispersing 50 parts of vinyl acetate copolymer resin, 2 parts of thickener and 1 part of antifoaming agent. Further, a luster pigment (manufactured by Merck & Co., Ltd.) obtained by coating the surface of the flat glass piece with silicon dioxide on the upper layer of the reversible thermochromic layer 3 and further coating with titanium dioxide. Name: Miraval 5311 Scientific White, particle size 10-100 μm), 50 parts of ethylene-vinyl acetate copolymer resin, 2 parts of thickener, and 1 part of antifoaming agent, obtained by uniformly stirring and dispersing. After laminating and printing using ink to provide the glitter layer 2, a transparent polypropylene film having a thickness of 20 μm was laminated, and a protective layer 5 was provided to obtain a glittering and thermochromic laminate 1.

  When the reversible thermochromic layer 3 was visually recognized from the protective layer 5 side in a color development state (black) of 28 ° C. or less, the laminate 1 showed a bright metallic luster-like bright color. Moreover, when the reversible thermochromic layer 3 was decolored at 30 ° C. or higher, the bright color was not seen and the white laminate 1 was obtained. This aspect change could be repeated.

Example 4 (see FIG. 3)
A bright pigment formed by coating the surface of a flat glass piece with silicon dioxide on the upper layer of a transparent polyvinyl chloride film as support 4 and further coating with titanium dioxide (trade name: Miraval 5422 5426 Magic Green, manufactured by Merck & Co., Inc.). The particle size 20-200 μm) 10 parts, 50% acrylic resin / xylene solution 50 parts, xylene 30 parts, and methyl isobutyl ketone 30 parts were stirred and mixed with a spray gun to paint the glitter layer 2. And 10 parts of a reversible thermochromic microcapsule pigment as in Example 1, 50 parts of a 50% acrylic resin / xylene solution, 30 parts of xylene, and 30 parts of methyl isobutyl ketone, on the lower layer of the transparent polyvinyl chloride film. A reversible thermochromic layer 3 is provided by spray coating the mixed paint with a spray gun. To obtain a bright tone thermochromic laminate 1.

  When the reversible thermochromic layer 3 was visually recognized from the bright layer 2 side in a colored state (black color) of 15 ° C. or less, the laminate 1 showed a dark green bright color with high brightness. Further, when the reversible thermochromic layer 3 was decolored at 32 ° C. or higher, the chromatic color was not visible and the colorless laminate 1 was obtained. This aspect change could be repeated.

Example 5 (see FIG. 4)
After a bouquet pattern (non-thermochromic layer 6) is provided with a non-thermochromic pink ink on the surface of a white mug as the support 4, 2-anilino-3-methyl-6-dibutylamino is formed on the pattern. A thermochromic composition comprising 3 parts of fluorane, 6 parts of 4,4 '-(2-methyl-propylidene) bisphenol, 25 parts of stearyl alcohol and 25 parts of stearyl laurate was converted to an epoxy resin / amine curing agent interface. Reversible obtained by uniformly stirring and dispersing 50 parts of a reversibly thermochromic microcapsule pigment having an average particle diameter of 10 μm obtained by encapsulation by a polymerization method, 75 parts of an epoxy resin, 10 parts of an additive, and 40 parts of an amine curing agent. Photochromic ink, and a luster pigment formed by coating the surface of a flat glass piece with silicon dioxide and further with titanium dioxide (Merck, trade name: Mira) al 5311 Scientific White, particle size 10 to 100 μm) 20 parts, 75 parts of epoxy resin, 10 parts of additive, and 40 parts of amine curing agent are uniformly stirred and dispersed in a star pattern. Laminate printing was performed to obtain a bright tone thermochromic mug.

  When the reversible thermochromic layer 3 had a color development state (black) of 38 ° C. or lower, the bright-tone thermochromic mug showed a bright metallic star-like glitter. Further, when the reversible thermochromic layer 3 was decolored at 42 ° C. or higher, the star-colored bright color was not visible, and the pink bouquet pattern was visible. This aspect change could be repeated.

It is a longitudinal cross-sectional view of one Example of the glittering thermochromic laminate of the present invention. It is a longitudinal cross-sectional view of the other Example of the luster tone thermochromic laminated body of this invention. It is a longitudinal cross-sectional view of the other Example of the luster tone thermochromic laminated body of this invention. It is a longitudinal cross-sectional view of the other Example of the luster tone thermochromic laminated body of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Luminous thermochromic laminated body 2 Luminous layer 3 Reversible thermochromic layer 4 Support body 5 Protective layer 6 Non-thermochromic layer

Claims (4)

  A reversible thermochromic layer comprising a thermochromic composition comprising an electron-donating color-forming organic compound and an electron-accepting compound and an organic compound medium that reversibly causes a color reaction between the two, and the surface of the flat glass piece. A glitter thermochromic laminate obtained by laminating a glitter layer containing a glitter pigment coated with silicon dioxide and further coated with titanium dioxide.   The glitter thermochromic laminate according to claim 1, wherein a reversible thermochromic layer and a glitter layer are sequentially laminated on a support.   The glitter thermochromic laminate according to claim 1, wherein a glitter layer and a reversible thermochromic layer are sequentially laminated on a transparent support.   The glitter thermochromic laminate according to claim 1, wherein a transparent support is interposed between the glitter layer and the reversible thermochromic layer.