JPH0636863U - Reversible thermochromic laminate - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a reversible thermochromic printed matter that effectively reveals a plurality of overprinted printed images. A thermochromic hiding layer 4 for covering the first printed image 3 formed on the surface of the support 2 is provided, and a metallic luster pigment layer 5 is laminated on the thermochromic hiding layer 4 to obtain the metallic luster pigment. A second printed image 6 is provided on the layer 5. [Effect] Due to the reflection and transmission characteristics of the metallic luster pigment layer 5,
The hiding property can be remarkably improved, and the thermochromic hiding layer 4 can be made black or a dark color having a high hiding property, and the degree of freedom can be given to the color, density, etc. of the underlying printed image.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a reversible thermochromic laminate. More specifically, the present invention relates to a reversible thermochromic laminate that reveals different printed images due to temperature changes. More specifically, the present invention relates to a reversible thermochromic laminate in which a printed image formed on a surface layer of gold, silver, or other metallic color is visualized and a printed image formed on the lower layer of the surface layer is revealed by a temperature change.

[0002]

[Prior art]

 Conventionally, a certain type of printed image is covered with a thermochromic hiding layer containing a thermochromic material that exhibits a reversible color change of colored ← → colorless and colored [1] ← → colored [2] due to temperature change, Several proposals have been disclosed regarding the thermochromic printed matter in which the printed image is hidden (for example, Japanese Utility Model Laid-Open No. 59-68972).

[0003]

[Problems to be solved by the device]

 In the conventional thermochromic concealment printing system described above, does the thermochromic concealment layer for concealing the image to be concealed have a visual density at the time of color development that satisfies the relationship of relatively dark visual density? However, it is necessary that the color tone at the time of color development is in the same system as the color tone of the printed image to be concealed, and the degree of freedom in the combination of color and density between the two is lacking. The present invention conceals the above-mentioned conventional problems, conceals the background image by a shielding layer having a concealing property and a unique color tone, and further forms another printed image on the shielding layer, which is different from the background image. However, the appearance of various concealed printed images of the base, the combination of the printed image on the surface, and the like to significantly enhance the nuances, unexpectedness, and decorativeness of the toy field, the interior field, the decorative field, and other fields. It is intended to provide a reversible thermochromic laminate that can be applied to and developed in.

[0004]

[Means for Solving the Problems]

 The reversible thermochromic laminate of the present invention will be described with reference to the drawings (see FIGS. 1 to 3). The reversible thermochromic layered product 1 of the present invention is a layered product configured to conceal different printed images by a temperature change, and the thermochromic property concealment covering the first printed image 3 formed on the support 2 surface. The layer 4 is provided, the metallic luster pigment layer 5 is laminated on the thermochromic hiding layer 4, and the second printed image 6 is provided on the metallic luster pigment layer 5. Furthermore, the metallic luster pigment layer 5 is required to be a layer in which a silver metallic luster pigment is fixed to a transparent resin in a dispersed state. In the above description, the support 2 is not limited to a sheet material such as paper, plastic sheet, cloth, non-woven fabric, leather, etc., as long as it has printability or coating suitability, and is also glass, ceramic material, metal, wood, stone material, plastic. A variety of base materials that are suitable for the purpose, such as molded products made of materials, are effective. The first printed image 3 is not limited to a colored image with a non-thermochromic dye and pigment, but may be a thermochromic image with a thermochromic material. Further, the second printed image 6 may be a thermochromic image or a colored image with a non-thermochromic dye or pigment. The printed image 3 or the printed image 6 is not limited to the literally printed image, and may be formed by painting, spraying, or the like.

The thermochromic masking layer 4 and the thermochromic material for forming the thermochromic image are known electron-donating color-forming organic compounds, electron-accepting compounds, and the color reaction of both of them, which reversibly occur. A thermochromic material containing three components of an organic compound medium or a thermochromic material exhibiting a thermochromic property in the form of fine particles of a resin solid solution of the components (for example, JP-B-51-35414 and JP-B-51-44706). Gazette, Japanese Examined Patent Publication No. 1-29398, etc.). In addition, a thermochromic material (that is, a coloring density due to temperature change) containing a color memory memorable thermochromic dye disclosed in Japanese Patent Publication No. 4-17154, which has been already proposed by the present applicant, shows a large hysteresis characteristic and discolors. The shape of the curve that plots the change follows a path that changes greatly when the temperature is raised from the low temperature side of the discoloration temperature range to the temperature when it is lowered from the high temperature side of the discoloration temperature range. However, in the room temperature range between the low temperature side discoloration point and the high temperature side discoloration point, it is possible to memorize and retain the appearance of being changed at a temperature below the low temperature side discoloration point or above the high temperature side discoloration point).

The thermochromic material described above is usually encapsulated in microcapsules and dispersed in a resin-containing medium to form a second printed image 6 (or a first printed image 3) as ink or paint. ) And the thermochromic hiding layer 4 are formed. The metallic luster pigment layer 5 is a layer in which the metallic luster pigment is fixed to a transparent resin in a dispersed state, and is usually formed by applying an ink or paint in which the metallic pigment is dispersed in a medium containing a resin. It The layer 5 has a thickness of 10 to 400 μm, preferably 15 to 300 μm, and the content of the metallic luster pigment in the layer 5 is 0.1 to 40% by weight (preferably 0.5 to 30% by weight). It gives a proper concealment effect, light reflection effect, and light transmission effect. As the resin in the above, a general-purpose resin that has been conventionally applied to paints or printing inks is effective, and is selected and applied according to the purpose. Specific examples of the metallic luster pigments mentioned above include gold, silver, metallic red, metallic purple, metallic blue, and metallic green pigments in which the surface of natural mica particles is coated with titanium oxide, and the surface of natural mica particles is titanium oxide. Examples thereof include a golden metallic luster pigment and the like, which is coated with, and whose upper layer is coated with iron oxide. More specifically, the metallic luster pigment is a golden metallic luster pigment in which the surface of natural mica particles is coated with 41 to 44% by weight of titanium oxide, the optical thickness is 180 to 240 nm, and the grain size is 5 to 60 μm. Or the surface of natural mica particles is coated with 30 to 48% by weight of titanium oxide, and the upper layer thereof is coated with 4 to 10% by weight of iron oxide. The optical thickness is 180 to 240 nm and the particle size is 5 to 60 μm. Examples of the golden metallic luster pigment and the silver metallic luster pigment include those having a surface of natural mica particles coated with 16 to 39% by weight of titanium oxide and an optical thickness of 110 to 170 nm and a particle size of 5 to 100 μm. it can. Here, optical thickness = refractive index × geometrical thickness. The metallic red metallic luster pigment has a surface of natural mica particles coated with 45 to 47% by weight of titanium oxide and has an optical thickness of 245-275 nm. The metallic purple metallic luster pigment has a surface of natural mica particles. Metallic blue metallic luster pigment with an optical thickness of 280 to 310 nm, coated with 48 to 50% by weight of titanium oxide, is a light coated with 51 to 54% by weight of titanium oxide on the surface of natural mica particles. The metallic green metallic luster pigment has an optical thickness of 315 to 350 nm, and the surface of natural mica particles is coated with 55 to 58% by weight of titanium oxide. An example is a pigment of -60 μm. Further, as the metallic luster pigment, a dichroic metallic luster pigment in which the surface of natural mica particles is coated with titanium oxide and the upper layer thereof is coated with an organic pigment may be used. The metallic luster pigments with specific physical properties described above selectively transmit light of a certain wavelength and reflect light of a wavelength complementary to that of silver luster pigments that transmit and reflect all wavelengths in a specific ratio. It has the property of Outside the range of the above-mentioned specific physical property values, the wavelength selectivity is lost, or there is wavelength selectivity but the desired color is not obtained.

The thermochromic hiding layer 4 and the metallic luster pigment layer 5 are formed by a conventionally known method, for example, printing means such as screen printing, offset printing, gravure printing, coater, tampo printing, transfer, brushing and spraying. It can be carried out by means of coating, electrostatic coating, electrodeposition coating, flow coating, roller coating, dip coating and the like.

[0008]

[Action]

 The thermochromic concealing layer 4 and the metallic luster pigment layer 5 laminated on the layer are in a concealed state. The first printed image 3 is concealed by a temperature change. At this time, the color change of the thermochromic hiding layer 4 is visualized through the metallic luster pigment layer 5, and the wavelength of visible light is selected by applying the metallic luster pigment having the above-mentioned specific physical property values. Synergistic effect of iris effect, transmission effect, and reflection / absorption effect of visible light with lightness value of thermochromic layer, which are caused by dynamic interference effect, makes various color changes of metallic luster to be visible.

Specifically, it has a characteristic that reflected light at the time of interference changes depending on the coating weight% of the titanium oxide, that is, the thickness of the coating layer. For example, with titanium oxide-coated mica that has been prepared to selectively reflect yellow light and transmit blue light, when the base is black, the transmitted blue light is absorbed by the base black and yellow light is absorbed. Only the light is reflected, so it has a golden color. On the other hand, when the background is white, the transmitted blue light is also reflected by the white of the background, not only the yellow light but also the blue light is reflected, and all wavelengths of visible light are reflected. To be done. Therefore, by reversibly changing the lower thermochromic hiding layer 4 to black ← → white, a reversible color change of silver ← → white is visually recognized. The metallic luster pigment layer 5 of the present invention is particularly effective with a system of a silver metallic luster pigment, and this system will be described. Titanium oxide-coated mica, which is adjusted to absorb the rest of the light of all wavelengths of the incident light and reflect the rest of the light, is reflected in the same direction without diffuse reflection of the reflected light due to the layered characteristics of the mica. Because it is reflected, silver color is displayed instead of gray. The silver metallic luster color is an achromatic color and can maintain brightness (whiteness) as compared with a normal thermochromic hiding layer, and thus has a characteristic that a second image can be formed in any color on the upper layer. Therefore, when the thermochromic hiding layer 4 is colored, the first printed image 3 located therebelow can be formed without color limitation. Next, when the second printed image 6 (in the case of a thermochromic image) is decolored and the thermochromic hiding layer 4 is decolored at the same time, the silver color is decolored and the first printed image 3 of the base appears. In this phenomenon, the pattern changes completely before and after the change, and the image can be changed as if the page was turned. On the other hand, in the conventional hiding means using only the thermochromic hiding layer, the hiding layer is black or a dark dark color, and the non-hiding image (corresponding to the first printed image 3) is hidden, so that before the change. It was difficult to form various images in the state, and at most it was possible to form some image with a silhouette and substitute it for the second image. When the metallic luster pigment is metallic red, metallic purple, metallic blue, metallic green, etc., the same action as described above allows various color changes from the metallic luster tones to be visualized, thereby providing a concealing effect. Play.

Although the visual state of the first printed image 3 (characters, patterns, etc.) is hindered by the coloring state of the thermochromic hiding layer 4, the hiding effect is remarkably improved by the light reflection effect of the metallic luster pigment layer 5. When the second printed image 6 formed on the metallic luster pigment layer 5 is a thermochromic image having the same discoloration temperature as the discoloration temperature of the thermochromic hiding layer 4, the second printed image 6 disappears. At the same time, the first printed image 3 is revealed. When the second thermochromic printed image 6 and the thermochromic hiding layer 4 have different color changing temperatures, a further multi-step visual change is exhibited. When the second printed image 6 is a non-thermochromic printed image, the first printed image 3 is visualized in addition to the visual perception of the printed image 6, and an image obtained by combining both images is visualized. The above-mentioned aspect of the visual change due to the temperature change is reversible and is repeatedly reproduced.

[0011]

【Example】

 Example 1 (see FIGS. 1 to 3) A printed image 3 of a butterfly was formed on a white fine paper 2 with commercially available yellow, pink, and blue non-thermochromic screen inks, and then a thermochromic pigment [ Print image of the butterfly using a thermochromic screen ink consisting of a dispersion of black ← → colorless, discoloration temperature of 30 ° C. (black below 30 ° C., reversibly discolors to colorless above 30 ° C.) A thermochromic hiding layer 4 having a thickness of about 40 μm, which covers 3 was formed by screen printing. Next, a screen ink containing a silver metallic luster pigment was used to form a metallic luster pigment layer 5 having a thickness of about 40 μm and covering the thermochromic hiding layer 4 by screen printing. Next, a thermochromic screen ink and a thermochromic pigment (green ← → colorless, discoloring temperature 30) which consist of a dispersion of thermochromic pigment (pink ← → colorless, discoloring temperature 30 ° C.) on the metallic luster pigment layer 5. A printed image 6 of caterpillars was formed by screen printing using a thermochromic screen ink composed of a dispersion of ° C). The obtained printed matter 1 shows the printed image 6 of green and pink caterpillars on the silver layer at room temperature, but when the whole is heated to 30 ° C. or higher, the printed image 6 of caterpillar becomes invisible and becomes silvery. The layers disappeared, revealing the printed image 3 of the butterfly. The printed image 3 of the butterfly returned to the visual image of the printed image 4 of the caterpillar when left at room temperature for a while, and the image of the caterpillar ← → butterfly could be reversibly visualized by the temperature change.

Example 2 A commercial aircraft design was formed on the surface of a styrene airplane toy by spray painting with white, fluorescent yellow, and fluorescent pink commercial non-thermochromic paints. Then, a thermochromic color memory paint consisting of a dispersion of thermochromic color memory pigment (black ← → colorless, low temperature side temperature: 15 ° C, high temperature side temperature: 35 ° C) was sprayed on the entire surface of the airplane. The coating was performed to form a thermochromic hiding layer having a thickness of about 40 μm. Next, a spray paint containing a silver luster pigment was sprayed on the thermochromic hiding layer to form a silver metallic luster layer having a thickness of about 35 μm. Furthermore, a thermochromic color memory pigment composed of a dispersion of thermochromic color memory pigment (blue ← → colorless, low temperature side temperature: 15 ° C, high temperature side temperature 35 ° C) in the upper layer is spray-painted with a memory memory paint to design a military aircraft. Was formed. The resulting airplane toy transformed into a military aircraft design when cooled below 15 ° C and was maintained at room temperature. Next, when heated to 35 ° C or higher, the design of the military aircraft in blue disappeared, and the design of the civilian aircraft colored in fluorescent yellow and fluorescent pink appeared in white, and this design was maintained at room temperature.

Example 3 On a white polyvinyl chloride sheet, the letters "Cat" were printed with a light pink non-thermochromic oily screen ink, and then a thermochromic pigment (red ← → colorless, discoloration temperature A cat pattern was printed using a thermochromic screen ink composed of a dispersion having a temperature of 40 ° C.) so as to conceal the character “cat”. Next, using a thermochromic screen ink consisting of a dispersion of thermochromic pigment (black ← → colorless, discoloration temperature 30 ° C), screen printing was performed on the cat pattern (thermochromic hiding layer), and the thermochromic color was changed. A sex masking layer was formed. Next, a silver metallic luster pigment layer was formed using a screen ink containing a silver metallic luster pigment. Next, the character "CAT" was screen-printed on the silver metallic luster pigment layer using a thermochromic screen ink consisting of a dispersion of thermochromic pigment (blue ← → colorless, discoloration temperature 30 ° C). . At room temperature, the sheet obtained has a blue "CAT" text visible on silver, but when the whole was heated above 30 ° C, the "CAT" text disappeared and a red cat design appeared. . Further, when heated to 40 ° C or higher, the red cat pattern disappeared and the light pink character "cat" appeared. After a while, the "cat" character returns to the red cat design, then returns to the blue "CAT" character, and the "CAT", cat design, and "cat" visual and invisible. The change in appearance was reversibly reproduced by the change in temperature.

[0014]

EFFECTS OF THE INVENTION The thermochromic laminate of the present invention has a metallic luster pigment layer laminated on a thermochromic concealment layer, and the concealability is remarkably improved by the reflection and transmission characteristics of the metallic luster pigment layer. As a thermochromic hiding layer, it can be formed in black or a dark color having a high hiding property, and gives flexibility in selecting the color, density, etc. of the printed image of the base. The metallic luster pigment layer can be selected from gold, silver and other metallic colors, and further enhances the concealment effect of the undercoat in combination with the uniqueness of the color. Furthermore, an appropriate image can be formed on the metallic luster pigment layer so that it can be visualized, and the strangeness and unexpectedness due to the visual change due to the temperature change are enhanced. In particular, when a silver-colored metallic luster layer is applied, printed images of various colors and densities can be formed on the layer without any restrictions on the colors and densities. Thus, it is possible to provide a reversible thermochromic laminate that can be applied to various fields such as toys, decorations, teaching materials, stationery, textiles, household products, and printed matter.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional explanatory view of an embodiment of a reversible thermochromic laminate of the present invention.

FIG. 2 is an explanatory plan view showing a state in which a second print image is visualized.

FIG. 3 is an explanatory plan view showing a state in which a second print image has disappeared and the first print image is visualized.

[Explanation of symbols]

 1 Thermochromic Laminate 2 Support 3 First Printed Image 4 Thermochromic Hiding Layer 5 Metallic Luster Pigment Layer 6 Second Printed Image

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C09D 5/29 PSD 7211-4J 7/12 PSJ 7211-4J

Claims (2)

[Scope of utility model registration request] 1. A thermochromic concealing layer 4 for covering a first printed image 3 formed on a surface of a support 2 in a laminate for concealing different printed images due to temperature change, the thermochromic concealment A reversible thermochromic laminate comprising a metallic luster pigment layer 5 laminated on the layer 4 and a second printed image 6 provided on the metallic luster pigment layer 5. 2. The reversible thermochromic laminate according to claim 1, wherein the metallic luster pigment layer 5 is a layer in which a silver metallic luster pigment is fixed to a transparent resin in a dispersed state.