JP2000062326A - Reversible heat-sensitive recording sheet and information display medium using the sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a heat-sensitive recording sheet for amplifying the contrast of record display of a heat-sensitive recording layer, improve visual recognition properties thereof and also improve the decoration properties thereof by the display effect and provide an information display medium thereof. SOLUTION: A reversible heat-sensitive recording sheet 1 is formed of a multi-layer 22 formed of two layers or more of a ceramic film displaying a plurality of different optical characteristics of a metal film or a composite film of the ceramic film and the metal film and a reliable heat-sensitive recording layer 23 having transparency varied reversely depending on the temperature laminated together successively on a base 21, and not only visual recognition properties of the display are improved but also the decoration properties varying the color based on the visual angles by utilizing the color shaft are improved simultaneously by using the multi-layer film layer 22 for amplifying the contrast of the recording display of the reversible heat-sensitive recording layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rewritable heat-sensitive recording sheet having a recording layer whose transparency reversibly changes depending on temperature, and for example, a membership card, I
D card, credit card, cash card, IC
The present invention relates to an information display medium used for cards and the like.

[0002]

2. Description of the Related Art In recent years, a display medium using a reversible thermosensitive recording material has attracted attention. As a reversible thermosensitive recording material,
For example, phase-change recording materials and magneto-optical recording materials having light absorption characteristics, thermal dye recording materials that develop / decolor by combining a leuco dye with a developer and a decolorizer, polymer compounds and organic low-molecular compounds. Recording materials that change the transparency by utilizing the difference in melting and solidification behavior, recording materials that use the phase change of polymer compounds, recording materials in which liquid crystal is dispersed in polymer compounds, and the like are used.

In particular, regarding the membership card, ID card, credit card, cash card, IC card, etc., there is a great demand for a card capable of reversibly recording and erasing characters, symbols, figures, etc. For example, a heat-sensitive recording material comprising a mixture of a polymer compound and an organic low-molecular compound dispersed in the polymer, which is known from JP-A-5-85045, is mainly used as a reversible display material for these cards. Has been.

Cards having a reversible display section utilizing these thermal recording techniques are, for example, point cards, membership cards, IC cards, etc., which are media for displaying the number of points acquired, information guidance to members, and the like. The recording method and the erasing method are well known.

As a method of producing these information display media, a method of directly providing a heat-sensitive recording layer on a card substrate by a printing method, a coating method or the like is mainly adopted. In addition, for plastic cards such as membership cards, ID cards, and IC cards, a method is also used in which a thermosensitive recording layer is provided on another plastic support and a sheet-shaped thermosensitive recording medium is provided on the card via an adhesive or the like. Has been done.

[0006]

However, a heat-sensitive recording material comprising a mixture of the above-described polymer compound and an organic low-molecular compound dispersed in the polymer compound has a small difference in shade between the colored portion and the non-colored portion, and is not changed. However, there is a problem that it is difficult to visually confirm the display.By providing a metal reflection layer or a dark color layer under the thermal recording layer, the difference in light and shade is amplified by the metal reflection layer, etc. I am able to confirm. Therefore, there is a problem in that the design of the display unit can be restricted because the display unit becomes a dark color such as silver or black. Therefore, the present invention provides a heat-sensitive recording sheet in which the contrast of the recorded display on the heat-sensitive recording layer is amplified to improve the visibility and the decorativeness is improved by the display effect, and an information display medium using the same.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the invention according to claim 1 relates to a ceramic thin film, a metal thin film, or a ceramic thin film showing a plurality of different optical characteristics on a substrate. A multilayer thin film layer formed by stacking two or more composite thin films of a thin film and a metal thin film, and a rewritable thermosensitive recording layer whose transparency reversibly changes depending on temperature are sequentially stacked. It is a reversible thermosensitive recording sheet.

According to a second aspect of the invention, in the reversible thermosensitive recording sheet according to the first aspect, an adhesive layer is provided on the opposite surface of the base material provided with the multilayer thin film layer and the thermosensitive recording layer. .

According to a third aspect of the present invention, a peeling protective layer, a plurality of ceramic thin films having different optical characteristics, a metal thin film, or a composite thin film of a ceramic thin film and a metal thin film is laminated on a base material. A reversible thermosensitive recording sheet comprising a multi-layered thin film layer, a rewritable thermosensitive recording layer whose transparency reversibly changes depending on temperature, and a transfer foil structure in which an adhesive layer is sequentially laminated.

According to a fourth aspect of the present invention, there is provided a ceramic thin film, a metal thin film, or a composite thin film of a ceramic thin film and a metal thin film, which exhibits a plurality of different optical characteristics on a substrate.
A multi-layered thin film layer consisting of at least two layers and a rewritable thermosensitive recording layer whose transparency reversibly changes depending on temperature are sequentially laminated, and a magnetic recording layer and a protective layer are sequentially arranged on the opposite surface of the substrate. An information display medium characterized by being provided.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view showing an embodiment of the reversible thermosensitive recording sheet of the present invention, FIG. 3 is a sectional view taken along line XX of the reversible thermosensitive recording sheet of FIG. 1, and FIG. Figure 3
FIG. 4 is an enlarged view of a multilayer thin film layer portion in the sectional view of FIG. 4, and FIG. 4 is an abandoned view showing one embodiment of the reversible thermosensitive recording sheet of the present invention. 5 is a sectional view showing an embodiment of the reversible thermosensitive recording foil of the present invention, and FIG. 6 is a sectional view showing an embodiment of the information recording medium of the present invention. The numbers in the figure are
The same numbers are used for the same configurations.

The reversible thermosensitive recording sheet 1 of the present invention shown in FIG.
Is, as shown in the cross-sectional view of the reversible thermosensitive recording sheet of FIG.
And a protective layer 25. The multilayer thin film layer 22 includes a high refractive index layer 12 which is the first thin film layer, a low refractive index layer 13 which is the second thin film layer, and a third thin film layer as shown in the cross-sectional view of the multilayer thin film layer of FIG. A certain high refractive index layer 14 is sequentially laminated. From its appearance, it has a reflection / transmission characteristic in a specific wavelength range utilizing the optical characteristic of the thin film in which the multilayer thin film layer 22 is laminated through the protective layer 25 in FIG. The reflection / transmission characteristics are changed depending on the position to be observed, and the effect of color shift (color change of reflected light) in which the visible color is different is seen, and the reversible thermosensitive recording layer 23 provided on the multilayer thin film layer 22 is observed. The contrast of the recorded display is amplified, the visibility of the display by visual observation is enhanced, and at the same time, the effect of color shift has the effect of enhancing decorativeness. In addition, the multilayer thin film layer may be five layers, seven layers, or more than the above three layers of high refractive index layer / low refractive index layer / high refractive index layer. However, in order to have the effect of color shift, it is preferable to dispose a high refractive index layer as an outer layer and alternately arrange a high refractive index layer and a low refractive index layer.

The base material 21 is selected from synthetic resins such as polyethylene terephthalate, polyvinyl chloride, polyester, polycarbonate, polymethylmethacrylate and polystyrene, films of natural resin, synthetic paper, paper, etc., or the above. It is possible to use a composite or the like selected from the above materials and combined. Considering workability and operability, these base materials have a thickness of 4 with excellent physical properties.
It is appropriately selected from the range of μm to 210 μm according to the application.

The multi-layer thin film layer 22 is composed of multi-layer thin films having different optical aptitudes as described above, and is formed by laminating as a metal thin film, a ceramic thin film or a composite thin film in which they are provided side by side. For example, thin films having different refractive indexes. When laminating, a thin film having a high refractive index and a thin film having a low refractive index may be combined, or a specific combination may be laminated alternately. A desired multilayer thin film can be obtained by a combination thereof.

For example, a high-refractive index material having a refractive index of about 2 or more and a low-refractive index material having a refractive index of about 1.5 are laminated in a predetermined film thickness. Specifically, as a ceramic, Sb ₂ O ₃ (refractive index n = 3.0: same below), Fe
₂ O ₃ (2.7), TiO ₂ (2.6), CdS (2.
6), CeO ₂ (2.3), ZnS (2.3), PbC
l ₂ (2.3), CdO (2.2), Sb ₂ O ₃ (2.
0), WO ₃ (2.0), SiO (2.0), Si ₂ O
₃ (2.5), In ₂ O ₃ (2.0), PbO (2.
6), Ta ₂ O ₃ (2.4), ZnO (2.1), Zr
O ₂ (2.0), MgO (1.6), SiO ₂ (1.
5), MgF ₂ (1.4), CeF ₃ (1.6), Ca
F ₂ (1.3 to 1.4), AlF ₃ (1.6), Al ₂
O ₃ (1.6), GaO (1.7), etc., which are thin films of a simple metal or an alloy, such as Al, Fe, Mg, Zn,
There are Au, Ag, Cr, Ni, Cu, Si and the like. Also,
Low refractive index organic polymers such as polyethylene (1.5
1), polypropylene (1.49), polytetrafluoroethylene (1.35), polymethylmethacrylate (1.49), polystyrene (1.60) and the like. By selecting at least one of these high-refractive index materials or metal thin films of 30% to 60% transmission, and at least one of low-refractive index materials, and alternately stacking them with a predetermined thickness,
It shows absorption or reflection of visible light of a specific wavelength. Since the thin film made of metal has different optical characteristics such as a refractive index depending on the state of the constituent materials, the forming conditions, etc., the values under certain conditions are used in the embodiments of the present invention.

The above-mentioned materials are appropriately selected on the basis of optical properties such as refractive index, reflectance and transmittance, weather resistance, chemical resistance, interlayer adhesion, etc. and laminated as thin films to form a multilayer thin film. A known method can be used as the forming method, and the film thickness, the film forming rate, the number of stacked layers, or the optical film thickness (= n × d,
A physical vapor deposition method such as an ordinary vacuum deposition method or a sputtering method or a chemical vapor deposition method such as a CVD method, which can control n: refractive index, d: film thickness, etc., can be used. Further, as a method for forming a low refractive index organic polymer,
Known printing methods such as gravure printing, offset printing, screen printing, and coating methods such as bar coating, gravure coating, and roll coating can be used. Although only the ceramics / metals are disclosed in the present invention, any ceramics / metals having the same or similar refractive index and reflectance as the ceramics / metals can be used.

Further, as a specific example of the multilayer thin film layer 22, the layer thickness is in the range of 50 to 2000 nm, and the layer structure of the thin film is a thin film made of the above-mentioned high refractive index material or metal material, for example ZnS. , TiO ₂ , Zr
O ₂ , In ₂ O ₃ , SnO, ITO, CeO ₂ , Zn
O, Ta ₂ O ₃ , Al, Fe, Mg, Zn, Au, A
g, Cr, Ni, Cu, Si, etc. and a thin film made of the above-mentioned material having a low refractive index, for example, MgF ₂ , SiO ₂ , Ca
It is a combination with F ₂ , MgO, Al ₂ O _3, etc.,
They are laminated alternately, and the number of layers is two or more,
Preferred are those having 2 to 9 layers, but the optical characteristics of the multilayer film differ depending on the materials and combinations used, and therefore the present invention is not limited to this.

When the base material 21 on the multilayer thin film layer 22 is an organic polymer having a low refractive index, it is desirable that the first thin film layer in contact with this base material has a high refractive index. Generally, the spectral characteristics change according to the number of layers. Although not shown, a colored layer (not shown) is provided with a colored transparent ink or the like so as to be positioned on the base material or the multi-layer thin film layer, so that the color change becomes more diversified and easier to see. Can be improved.

The reversible thermosensitive recording layer 23 reversibly changes its cloudiness / transparency according to the change in the crystalline state of the organic low molecular weight substance dispersed in the matrix of the resin matrix, and is of a polymer / low molecular type. Can be classified. The high-molecular / low-molecular type reversibly changes the cloudiness and transparency due to the change in the crystalline state of the organic low-molecular substance dispersed in the matrix of the resin base material. The film thickness is 4 μm due to the printing method, coating method, etc. The thickness can be set to about 20 μm. Examples of the organic low molecular weight substance dispersed in the heat-sensitive recording layer include fatty acids or fatty acid derivatives or alicyclic organic acids, and more specifically, saturated or unsaturated ones or dicarboxylic acids, or esters thereof, A compound containing amide or the like is used, but it is not particularly limited.
Specific examples of the saturated fatty acids include undecanoic acid, lauric acid, myristic acid, pentadecanoic acid, palmitic acid, heptadecanoic acid, stearic acid, nanodecanoic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, melicinic acid. And the like, and specific examples of the unsaturated fatty acid include oleic acid, elaidic acid, linoleic acid, sorbic acid, stearolic acid and the like.
In addition, fatty acid or fatty acid derivative or alicyclic derivative e4e4e4e4e4
The e4e4e4e4ae organic acid is not limited to these, and it is also possible to apply one kind or a mixture of two or more kinds of these. As the resin base material used, an acrylic resin, a urethane resin, a polyester resin, a cellulose acetate resin, a nitrocellulose resin, a vinyl chloride resin, a vinyl acetate resin, alone, mixed or co-used. A polymer is used. On the other hand, in order to control the transparentization temperature range of the reversible thermosensitive recording area, 0.1% to 20% by weight of a resin plasticizer, a high boiling point solvent, etc. can be added to the resin base material. Furthermore, in order to improve the repeated printing and erasing resistance of the reversible thermosensitive recording area, a curing agent, a cross-linking agent, etc. for three-dimensional crosslinking corresponding to the resin base material is added to the resin base material in an amount of 0.5% to 10% by weight. can do.

The protective layer 25 plays a role of protecting the thermal recording layer 22 from physical rubbing of a thermal head or the like, and stimulus of sweat, chemicals or the like, and has a film thickness of 0 by a printing method or a coating method. The thickness can be set to about 2 to 10 μm.

Examples of the resin used include acrylic resin, urethane resin, vinyl chloride resin-vinyl acetate copolymer resin, polyester resin, melamine resin,
A conventionally known thermoplastic resin such as an epoxy resin, a polystyrene resin, or a polyimide resin, a thermosetting resin, an ultraviolet ray or electron beam curing resin may be used alone or in a mixture. Further, in order to improve resistance and prevent sticking during recording, a curing agent that crosslinks the resin, wax such as polyethylene washes, carnauba wax, and silicon wax, or calcium carbonate, zinc stearate, silica, alumina, talc. Other extender pigments such as, and oils and fats such as silicone oils and fats can be added to the extent that transparency is not impaired. Further, when recording / erasing with a thermal head, heat conductivity is controlled, so that hollow fillers, beads and the like can be added within a range not impairing transparency.

The information display medium 4 shown in FIG. 6 is formed by laminating the multi-layered thin film layer 22, the reversible thermosensitive recording layer 23 and the protective layer 25 on the above-mentioned base material 21, and on the base material 21 on the opposite side thereof. The magnetic recording layer 24 is formed on the reversible thermosensitive recording layer 2
The magnetic information using the magnetic recording layer 24 can be held together with the recording and erasing of the visible information by the method 3, and the magnetic information and the visible information can be recorded on the same medium. The magnetic recording layer 24 is formed of, for example, γ-Fe ₂ O ₃ , C
o Deposition γ-Fe ₂ O ₃ , Fe ₃ O ₄ , CrO ₂ , Fe,
Fe-Cr, Fe-Co, Co-Cr, Co-Ni, M
It is provided by applying a magnetic coating material composed of a dispersion liquid of fine magnetic particles such as nAl, Ba ferrite and Sr ferrite. Generally, a magnetic material used for a magnetic recording medium such as a prepaid card has a coercive force of 300 to 3000 (Oe) and a residual magnetic flux of 1.
0 to 2.0 (Maxwell / cm).

The concealment layer 26 does not interfere with the design of the printing layer (not shown) provided on the upper layer of the concealing layer 26 due to the color of the magnetic paint of the magnetic recording layer 24, which is brown or black. It can be provided if necessary, and can be omitted when unnecessary.

The concealing layer 26 is usually composed of ink, for example, acrylic resin, polyester resin, polyurethane resin, epoxy resin or the like, and a pigment such as titanium oxide, magnesium oxide or barium sulfate mixed therein. There is a method for forming the concealing layer, and there are conventionally known printing methods such as a gravure printing method, a screen printing method, and an offset printing method, which can be appropriately selected according to the application.

In the reversible thermosensitive recording sheet 2 shown in FIG. 4, a multi-layered thin film layer 22 and a reversible thermosensitive recording layer 23 are provided on the above-mentioned base material 21.
And a protective layer 25 are laminated, and the adhesive layer 27 is provided on the base material 21 on the opposite side to the other base material such as a card,
It is intended to be integrated with other objects such as sheets, forms, containers, bags, etc., and a polymer material having a softening point of 150 ° C. or lower is formed by a printing method or a coating method to have a film thickness of 0.5 μm to 10 μm.
Can be applied and provided.

As the polymer material, polyvinyl chloride, polyvinyl acetate, polyester resins, polyethylene resins, polyurethane resins, acrylic resins, homopolymers, mixtures or copolymers, elastomers and the like are used. Preferably, polyvinyl chloride, polyurethane resin and polyester resin are used.

In the reversible thermosensitive recording sheet 3 having the transfer foil structure shown in FIG. 5, the base material 31 is laminated with the peeling protection layer 28, the reversible thermosensitive recording layer 23, the multilayer thin film layer 22, and the adhesive layer 27. The reversible heat-sensitive recording sheet 3 can be easily transferred from the base material 31 to a transfer medium (not shown) such as a card support, and physical rubbing of a thermal head or the like, sweat, chemicals, etc. It plays a role of protecting the heat-sensitive recording layer 23 from irritation, and can be provided with a film thickness of about 0.2 to 10 μm by a printing method, a coating method, or the like. Examples of the resin used include conventionally known acrylic resins, urethane resins, vinyl chloride resins-vinyl acetate copolymer resins, polyester resins, melamine resins, epoxy resins, polystyrene resins, polyimide resins, etc. A thermoplastic resin, a thermosetting resin, an ultraviolet ray or electron beam curing resin may be used alone or as a mixture. Further, in order to improve resistance and prevent sticking during recording, a curing agent that crosslinks the resin, wax such as polyethylene washes, carnauba wax, and silicon wax, or calcium carbonate, zinc stearate, silica, alumina, talc. It is possible to add extender pigments such as, and oils and fats such as silicone oils and fats within a range that does not impair the transparency e4e4e4e4
e4e4e4e4e4ab. Further, when recording / erasing with a thermal head, the thermal conductivity is controlled, so hollow fillers, beads, etc. can be added within a range that does not impair transparency.

[0028]

EXAMPLES The present invention will be described in detail with reference to specific examples.

Example 1 A white polyethylene terephthalate (PET) resin sheet having a thickness of 188 μm is used as a base material,
A multilayer thin film layer having the following [composition of thin film layers] was formed on the substrate by a vacuum vapor deposition method. Subsequently, a thermosensitive recording layer ink having the following [reversible thermosensitive recording layer composition] was applied by a gravure method at a drying temperature of 130 ° C. and a coating thickness of 9 μm. A resin for a protective layer having the following [protective layer composition 1] was applied to the upper layer by a gravure method at a drying temperature of 100 ° C. and a coating thickness of 4 μm. In addition, a magnetic layer ink comprising the following [composition of the magnetic recording layer] was applied to the opposite side of the white PET substrate by a microgravure method at a drying temperature of 100 ° C. and a coating thickness of 15 μm.
m coating, and an ink for a hiding layer having the following [hiding layer composition] was applied to the upper layer at 110 ° C. by a gravure method at a coating thickness of 2
A reversible thermosensitive recording display medium was obtained by coating the reversible thermosensitive recording sheet in a card shape.

[Composition of Thin Film Layer] Metal thin film layer (high refractive index side) Al 20 nm low refractive index layer SiO ₂ 580 nm metal thin film layer Al 70 nm It should be noted that, of the base material / high refractive index side metal thin film layer / low refractive index layer order,
Alternatively, they are provided in the order of substrate / high refractive index side metal thin film layer / low refractive index layer / high refractive index metal thin film layer / low refractive index layer.

[0031] [Composition of reversible thermosensitive recording layer]   Behenic acid 16 parts by weight   Sebacic acid 4 parts by weight   Vinyl chloride / vinyl acetate copolymer resin (Solvine A: Shin-Etsu Chemical) 12 parts by weight   60 parts by weight of tetrahydrofuran   20 parts by weight of toluene

[0032] [Composition 1 of protective layer]   Acrylic resin (BR-116: Mitsubishi Rayon) 50 parts by weight   Teflon Fila (Hostaflon TF9202: Hoechst) 1.5 parts by weight   Calcium carbonate (white luster O: Shiraishi industry) 1.5 parts by weight   70 parts by weight of toluene   Methyl ethyl ketone 70 parts by weight

[0033] [Composition of magnetic recording layer]   Magnetic powder (1750 Oe: barium ferrite) 100 parts by weight   Vinyl chloride-vinyl acetate copolymer (VAGF: Union Carbide)                                                             20 parts by weight   Polyurethane resin (Nipporan 2304: Nippon Polyurethane Industry)                                                             30 parts by weight  Hexamethylene diisocyanate (Coronate HX: Nippon Polyurethane Industry)                                                               2 parts by weight   Carbon black (# 3000: manufactured by Mitsubishi Kasei) 5 parts by weight   Dispersant (Garfuck RE-610: manufactured by Toho Chemical Co., Ltd.) 3 parts by weight   Diluting solvent (toluene / MEK / MIBK) 100 parts by weight

[0034] [Composition of hiding layer]   Aluminum paste (aluminum paste: manufactured by Toyo Alumina Co., Ltd.) 25 parts by weight   Vinyl chloride-vinyl acetate copolymer (VAGF: Union Carbide)                                                             55 parts by weight   Cyclohexanone 15 parts by weight   Butyl Cello Sorobu 15 parts by weight

The reversible thermosensitive recording medium thus obtained was applied with a thermal head at an applied energy of 0.4 mJ / dot.
The printing data could be erased with a thermal head at an applied energy of 0.2 mJ / dot. The color of the display portion changed depending on the viewing angle, so that a heat-sensitive recording display medium having a good decorative property was obtained.

Example 2 A transparent polyethylene terephthalate (PET) resin sheet having a thickness of 25 μm was used as a base material, and a multilayer thin film layer composed of the above [composition of thin film layers] was formed on the base material by a vacuum vapor deposition method. Subsequently, the ink for the thermosensitive recording layer comprising the above [composition of the reversible thermosensitive recording layer] was applied by a gravure method at a drying temperature of 130 ° C. and a coating thickness of 9 μm. The protective layer ink comprising the above [protective layer composition 1] was dried on the upper layer by a gravure method at a drying temperature of 100 ° C. and a coating thickness of 4 μm.
Applied. Further, an ink for an adhesive layer comprising the following [composition of adhesive layer] was applied to the opposite surface of the transparent PET substrate by a gravure method at a drying temperature of 100 ° C. and a coating thickness of 3 μm to obtain a reversible thermosensitive recording sheet.

This reversible thermosensitive recording sheet was prepared in advance on a card support (not shown) made of a white vinyl chloride sheet having a total thickness of 760 μm and having a total thickness of 760 μm by a laminating method with a size of 10 mm length × 40 mm width and a transfer temperature of 110.
Adhesion was performed under the condition of 10 ° C for 10 minutes to form a card. The obtained card as an information display medium can be printed with a thermal head at an applied energy of 0.4 mJ / dot, and the print data can be erased with a thermal head at an applied energy of 0.2 mJ / dot. It was Also,
The color of the display portion changed depending on the viewing angle, so that a heat-sensitive recording medium having a good decorative property was obtained.

Example 3 A transparent polyethylene terephthalate (PET) resin sheet having a thickness of 25 μm was used as a base material, and an ink for a release protective layer consisting of the following [protective layer composition 2] was formed on the base material using a gravure method. C., coating thickness 4 .mu.m, then the above-mentioned [reversible thermosensitive recording layer composition] ink for thermal recording layer is applied by a gravure method at a drying temperature of 130.degree. Composition] was formed by a vacuum vapor deposition method. On top of that, an adhesive layer ink comprising the above [composition of the adhesive layer] was applied by a gravure method at a drying temperature of 100 ° C. and a coating thickness of 3
Then, a reversible thermosensitive recording transfer foil sheet was obtained.

[0039] [Composition 2 of protective layer]   Acrylic resin (BR-80: Mitsubishi Rayon) 50 parts by weight   Teflon Fila (Hostaflon TF9202: Hoechst) 1.5 parts by weight   Calcium carbonate (white luster O: Shiraishi industry) 1.5 parts by weight   70 parts by weight of toluene   Methyl ethyl ketone 70 parts by weight

This reversible thermosensitive recording sheet was prepared in advance by a hot stamping method on a card support (not shown) made of a white vinyl chloride sheet having a total thickness of 760 μm and having a total thickness of 760 μm and a transfer temperature of 10 mm × 40 mm. Two
A card was formed by transferring under conditions of 30 ° C. and 0.5 seconds.
The obtained card as an information display medium can be printed with a thermal head at an applied energy of 0.4 mJ / dot, and the print data can be erased with a thermal head at an applied energy of 0.2 mJ / dot. It was The color of the display portion changed depending on the viewing angle, so that a heat-sensitive recording display medium having a good decorative property was obtained.

[0041]

INDUSTRIAL APPLICABILITY The reversible thermosensitive recording sheet of the present invention uses a multi-layered thin film layer as a reflection layer for amplifying the contrast of the recorded display of the reversible thermosensitive recording layer, thereby enhancing the visibility of the display by visual inspection. At the same time, the effect of color shift has the effect of enhancing the decorative property that the color changes depending on the viewing angle.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a reversible thermosensitive recording sheet of the present invention.

FIG. 2 is a cross-sectional view of a layer structure showing details of a multilayer thin film layer portion in FIG.

FIG. 3 is a sectional view taken along line XX of the reversible thermosensitive recording sheet of FIG.

FIG. 4 is a sectional view showing an embodiment of the reversible thermosensitive recording sheet of the present invention.

FIG. 5 is a sectional view showing an embodiment of the reversible thermosensitive recording sheet of the present invention.

FIG. 6 is a sectional view showing an embodiment of the information display medium of the present invention.

[Explanation of symbols]

1, 2, ... Reversible thermosensitive recording sheet 3 Reversible thermosensitive recording foil 1 ‥‥‥‥‥‥‥ Information display medium 21, 31 ... Base material 12 ‥‥‥‥‥‥‥ High refractive index layer 13: Low refractive index layer 14 ………………………… High refractive index layer 22 Multilayer thin film layer 23 Reversible thermosensitive recording layer 24 Magnetic recording layer 25 ‥‥‥‥‥‥ Protective layer 26 ........ Hiding layer 27 ... Adhesive layer 28 ........ Peeling protection layer

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2C005 HA08 JB04 JC02 KA06 KA15                       KA28 LA05                 2H111 HA07 HA18 HA23 HA24 HA34

Claims (4)

[Claims] 1. A ceramic thin film showing a plurality of different optical characteristics on a substrate, or a metal thin film, or a multi-layer thin film layer in which two or more composite thin films of a ceramic thin film and a metal thin film are laminated, and depending on temperature. A reversible heat-sensitive recording sheet comprising a rewritable heat-sensitive recording layer whose transparency changes reversibly and successively laminated. 2. The reversible thermosensitive recording sheet according to claim 1, wherein an adhesive layer is provided on the opposite surface of the base material provided with the multilayer thin film layer and the thermosensitive recording layer. 3. A peeling protection layer, a ceramic thin film having a plurality of different optical characteristics, or a metal thin film, or a multilayer thin film layer formed by laminating two or more composite thin films of a ceramic thin film and a metal thin film on a substrate, and a temperature. A reversible heat-sensitive recording sheet having a transfer foil structure in which a rewritable heat-sensitive recording layer whose transparency changes reversibly depending on the above, and an adhesive layer are sequentially laminated. 4. A ceramic thin film, or a metal thin film, or a multi-layer thin film layer in which two or more composite thin films of a ceramic thin film and a metal thin film are laminated on a base material, and a ceramic thin film showing a plurality of different optical characteristics, and a temperature-dependent multilayer thin film layer. An information display medium characterized in that a rewritable thermosensitive recording layer whose transparency changes reversibly is sequentially laminated, and a magnetic recording layer and a protective layer are sequentially provided on the opposite surface of the substrate.