JP2001347758A - Reversible heat sensitive recording medium and transfer sheet thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reversible heat sensitive recording medium, excellent in resistance to moisture or resistance to water without deteriorating the contrast of an image, or a transfer sheet, capable of transferring the reversible heat sensitive recording medium having such a merit. SOLUTION: The reversible heat sensitive recording medium A is provided on one side (an upper side surface in a diagram 1) of a film substrate 1 consisting of a synthetic resin such as polyethylene terephthalate or the like with an optical reflection surface or a metallic optical reflection layer 2 through aluminum metallizing or the like and a heat sensitive recording layer 3 provided on the layer 2. The heat sensitive recording layer 3 is obtained by blending an organic low molecular compound into a matrix consisting of a light permeable resin while a protective layer 4 consisting of a transparent resin such as acrylic resin or the like is superposed on the layer 3 and all of the layers are adhered and bonded to integrate them. A moisture resistant transparent film is formed on an interface between the metallic optical reflecting layer 2 and the heat sensitive recording layer 3 whereby the image contrast will not be deteriorated even under a high temperature condition in the employing condition of the heat sensitive recording medium A and the reversible heat sensitive recording medium excellent in resistance to moisture as well as resistance to water can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reversible thermosensitive recording medium capable of displaying and erasing a visible image depending on temperature, and a transfer of a reversible thermosensitive recording medium used for transferring the same to a metal reflecting surface. Regarding the sheet.

[0002]

2. Description of the Related Art As a recording material of a reversible thermosensitive recording medium capable of displaying or erasing a visible image, an organic low molecular compound whose transparency is reversibly changed by adjusting a heating temperature or a cooling rate after heating is used as a resin. A reversible thermosensitive recording material dispersed in a base material is known.

For example, Japanese Unexamined Patent Publication (Kokai) No. 63-41186 discloses that a predetermined organic low-molecular compound is dispersed in a suitable PVC resin base material such as a vinyl chloride-vinyl acetate copolymer and dispersed. A reversible thermosensitive recording material that displays an image by changing the transparency of each particle portion reversibly in accordance with the temperature to produce a transparent / opaque contrast in a large number of dots or a predetermined divided area is disclosed. .

Referring to FIG. 1, to manufacture a reversible thermosensitive recording medium, a metal foil such as aluminum or tin or a metal vapor-deposited layer is formed on a substrate 1 made of a synthetic resin film such as polyethylene terephthalate. A metal light-reflecting layer 2 is formed in advance, and a reversible thermosensitive recording material dissolved in an organic solvent is applied thereon and dried, and a liquid synthetic layer is formed on the formed thermosensitive recording layer 3. The protective layer 4 is provided by applying and drying a resin.

In many cases, the reversible thermosensitive recording medium has a structure in which the light-reflecting layer 2 is superimposed on the thermosensitive recording layer 3 so that the image contrast is enhanced as much as possible.

Further, as shown in FIG. 2, in order to efficiently manufacture such a sheet-like reversible thermosensitive recording medium, the back surface of the thermosensitive recording layer 3 (in FIG. An adhesive layer 7 is provided on the upper surface (the upper surface), and the surface side of the thermosensitive recording layer 3 (FIG.
In (a), as a transfer for heat-sensitive recording medium B ₁ to form a protective layer 4 on the lower surface) of the thermosensitive recording layer 3, a protective layer 4 further release agent layer 6 on the detachment base layer 5 A transfer sheet of a reversible thermosensitive recording medium is superposed.

[0007]

The above-described reversible thermosensitive recording medium having a laminated structure and a transfer sheet thereof are provided with a predetermined organic low-molecular compound as a heat-sensitive recording layer, comprising a vinyl chloride-vinyl acetate copolymer or another vinyl chloride resin base. It has a layer that is mixed in a dispersed state in the material, and a metal light reflection layer is provided on this layer in close or close proximity, and when water enters the PVC-based resin from the outside, the desorbed chlorine becomes hydrochloric acid. This causes a problem that the metal reflection layer is corroded.

When the metal light reflecting layer is corroded in this way, there arises a problem that the image contrast is reduced, the visibility is reduced, and the appearance of the recording medium is also deteriorated.

Therefore, the conventional reversible thermosensitive recording medium is
When used or stored in a high-humidity environment, the visibility of an image is likely to deteriorate, and for example, it cannot be used under the condition of being exposed to rain and dew outdoors.

In order to increase the moisture resistance of the light reflecting layer made of metal, various resins having good moisture resistance may be used as the resin base material, or a stabilizer for preventing the generation of radicals that corrode the metal in the resin may be used. Attempts have been made to add an antioxidant, but it has been impossible to sufficiently increase the moisture resistance, and adverse effects have occurred such as the recording / erasing characteristics of the reversible thermosensitive recording material becoming unstable.

As another method for improving the moisture resistance of the light reflection layer, an attempt has been made to form a waterproof resin layer (barrier layer) on the metal light reflection layer. However, the barrier layer and the light reflection layer are made uniform. In some cases, unevenness may occur without adhering to the surface, in which case the gloss of the light reflecting layer is reduced and the contrast of the image is reduced.

Accordingly, a first object of the present invention is to provide a reversible thermosensitive recording medium having excellent moisture resistance and water resistance so as to solve the above-mentioned problems and prevent image contrast from lowering. is there.

[0013] A second problem of the present invention is as follows.
An object of the present invention is to provide a transfer sheet capable of transferring a reversible thermosensitive recording medium excellent in moisture resistance and water resistance without lowering image contrast.

[0014]

Means for Solving the Problems In order to solve the above problems, in the invention of the present application relating to a reversible thermosensitive recording medium,
A reversible thermosensitive recording layer and a laminate having a metal light-reflective layer on the back side of the reversible thermosensitive recording layer. Visible images can be displayed and erased by reversibly changing the transparency of the reversible thermosensitive recording layer with temperature. The reversible thermosensitive recording medium is characterized in that the reversible thermosensitive recording layer contains an organic metal corrosion inhibitor.

In order to solve the above-mentioned problems, the second invention of the present application relating to a transfer sheet for a reversible thermosensitive recording medium comprises a reversible thermosensitive recording layer and a metal light reflection layer on the back side thereof. A laminated transfer thermosensitive recording medium is provided, and in a transfer sheet of a reversible thermosensitive recording medium in which the transfer thermosensitive recording medium is releasably superimposed on a release sheet, the reversible thermosensitive recording layer has an organic recording medium. Thus, a transfer sheet of a reversible thermosensitive recording medium characterized by containing a metal corrosion inhibitor was obtained.

In the above invention relating to the reversible thermosensitive recording medium or the invention relating to the transfer sheet, the organic metal corrosion inhibitor comprises an addition compound of a ketocarboxylic acid compound and ethylmorpholine, and a ketocarboxylic acid compound. It is an object of these inventions to employ an organic metal corrosion inhibitor comprising at least one compound selected from the group consisting of an addition compound with zirconium, a benzothiazole compound and an ammonium salt of the benzothiazole compound. It is preferable to ensure the effect.

In the reversible thermosensitive recording medium of the present invention or the transfer sheet thereof, since the reversible thermosensitive recording layer contains an organic metal corrosion inhibitor, a metal light-emitting layer provided on the reversible thermosensitive recording layer is provided. A transparent corrosion-inhibiting organic coating is formed on the surface of the reflective layer.

When a transparent organic film made of a predetermined organic metal corrosion inhibitor is formed at the interface between the metal light reflecting layer and the reversible thermosensitive recording layer in this manner, the transparent organic film from the outside of the reversible thermosensitive recording medium is exposed. The amount of moisture permeating through the reversible thermosensitive recording layer is reduced, and a nonconductive film made of an organic metal corrosion inhibitor is formed on the metal surface, and the nonconductive film made of the organic metal corrosion inhibitor reflects light. Because it adheres to the surface of the layer,
There is no gap for water to enter the surface of the light reflecting layer, and the moisture resistance and water resistance are significantly improved.

Even if a moisture-resistant transparent film made of a metal corrosion inhibitor is formed at the interface between the metal light reflection layer and the reversible heat-sensitive recording layer, such a film is transparent. It does not lower the contrast of the image on the recording medium.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the reversible thermosensitive recording medium according to the present invention will be described below with reference to the accompanying drawings.

A reversible thermosensitive recording medium A shown in FIG. 1 is an enlarged cross section of a reversible thermosensitive recording medium (embodiment) in the form of a film or a tape obtained by cutting the film into a narrow width.

The reversible thermosensitive recording medium A is made of a metal light which becomes an optical reflection surface by aluminum evaporation or the like on one surface (upper surface in FIG. 1) of a film-like substrate 1 made of a synthetic resin such as polyethylene terephthalate. The reflection layer 2 is provided, and the heat-sensitive recording layer 3 is provided thereon. The heat-sensitive recording layer 3 is obtained by blending a low-molecular organic compound with a base material made of a light-transmitting resin, and a protective layer 4 made of a transparent resin such as an acrylic resin is stacked thereon, and all the layers are brought into close contact with each other. It is bonded and integrated.

The heat-sensitive recording layer according to the present invention comprises a heat-sensitive recording material composition in which particles of an organic low-molecular compound that undergoes a reversible crystal or melting phase transition depending on temperature are dispersed in a resin base material. Has excellent properties such as heat resistance, transparency, film formability, and high-temperature elasticity, and is preferably a resin capable of maintaining such properties even under conditions of repeated rapid heating.

Specific examples of suitable base resin include polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic acid copolymer, vinyl chloride-vinyl acetate-alcohol copolymer, Other examples include vinyl acetate compounds, vinyl chloride copolymers, polyvinylidene chloride, vinylidene chloride copolymers, polyesters, polyamides, polystyrene, polymethyl (meth) acrylate, and copolymers thereof.

The low-molecular organic compound used in the heat-sensitive recording material is crystallized or melted into a non-crystalline state by heat treatment, and is, for example, a known organic compound such as an alkyl ester of a fatty acid having 12 or more carbon atoms. Low molecular compounds can be employed. Such an organic low-molecular compound may be a compound composed of a carboxylic acid, a dicarboxylic acid, a ketone, an ether, an alcohol, an ester, a derivative thereof, or the like, and may be used alone or in combination of two or more. it can.

Among the crystalline organic low molecular weight compounds, fatty acid alkyl esters having 12 or more carbon atoms have a low melting point (mp).
Which are crystallized or melted by heat treatment at a relatively low temperature. Furthermore, in addition to the fatty acid alkyl ester having 12 or more carbon atoms,
If the above aliphatic dibasic acids having a high melting point (mp) are used in combination and the mixing ratio of the fatty acid alkyl ester and the aliphatic dibasic acid is adjusted, it is possible to adjust the temperature range in which the liquid is made transparent. Sex and the degree of cloudiness can be varied.

Incidentally, examples of higher fatty acid esters composed of higher fatty acids having 12 or more carbon atoms and alcohols having 1 or more carbon atoms include methyl stearate, ethyl stearate, butyl stearate, octyl stearate, methyl behenate, Examples include ethyl behenate, butyl behenate, octyl behenate, methyl lignoserate, and ethyl lignocerate.

Further, the higher fatty acid or the higher fatty acid derivative constituting the higher fatty acid ester exemplified above is
Higher fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, lignoceric acid, and cerotic acid, or anhydrides thereof, and pentadecanol, heptadecanol, octadecanol, eicosanol, docosanol, tetra Alcohols such as cosanol and hexacosanol.

The organic metal corrosion inhibitor to be added to the heat-sensitive recording material used in the invention according to each claim of the present application is:
When the solvent is evaporated after being dissolved and added to the solvent, a transparent water-resistant film having good adhesion is formed at the interface between the light reflection layer and the heat-sensitive recording layer. Specific examples of such an organic metal corrosion inhibitor include an addition compound of a ketocarboxylic acid compound and ethylmorpholine, an addition compound of a ketocarboxylic acid compound and zirconium oxide, a benzothiazole compound and a benzothiazole compound. At least one compound selected from the group consisting of ammonium salts of

The ketocarboxylic acid compound includes 4-methyl-γ-oxo-benzenebutanoic acid.

Ethyl morpholine employs N-ethyl morpholine to obtain favorable results.

As the benzothiazole compound, 1-
(Benzothiazol-2-ylthio) succinic acid includes
And the ammonium salt of benzothiazole is 2-
(Benzothiazol-2-ylthio) succinic acid-dial
Kill ammonium and the like. Note that such
The alkyl in the ammonium salt is, for example, C₁₂~ C ₁₄
Are preferred.

The organic metal corrosion inhibitor described above reduces the moisture permeability of the layer containing the same, and
A nonconductive film is formed on the surface of the metal layer in contact with or in proximity to this layer to prevent or suppress metal corrosion. In addition, since the wettability and adhesion between the non-conductive film and the metal are good, there is no gap between the metal layer and the non-conductive film where moisture enters, and therefore, the anti-corrosion property is further improved.

The amount of the organic metal corrosion inhibitor, which is expected to exert the above effects, in the heat-sensitive recording material is 1 to 10 parts by weight, preferably 1 to 5 parts by weight, per 100 parts by weight of the recording material. is there. The reason is that if the amount is less than the predetermined range, the effect is insufficient, and if the amount is more than the predetermined range, the contrast of the reversible thermosensitive recording material may be reduced or erasure failure may occur. Because.

The metal light-reflective layer used in the present invention is a light-reflective layer containing a metal having good optical reflectivity for improving the visibility of an image, and is not particularly limited in the type of metal. It is. The light reflecting layer is intended to make the image formed on the recording layer easy to see from the surface, for example, a coating layer of a light reflecting paint mixed with aluminum or tin deposited or adhered to a foil or aluminum powder, Alternatively, a layer formed of a vapor-deposited film is preferable.

Judging from the viewpoints of color, gloss, cost, versatility and the like, it is particularly preferable to employ a deposited film of aluminum. Aluminum deposited film has a disadvantage that it is easily corroded by water, acid and alkali.Therefore, a thin metal such as chromium and silicone metal is deposited on the surface of the deposited film to withstand the color and luster of aluminum deposited without impairing the color and luster. It is also preferable to improve the corrosiveness.

As a method for forming a metal vapor-deposited layer such as an aluminum vapor-deposited film, a known method such as vacuum vapor deposition, sputtering, ion plating, and electron beam vapor deposition can be selectively employed.

When a metal deposition film is formed on the surface of a plastic film, not only the metal is directly deposited but also a colored or uncolored adhesive layer may be provided on the surface of the film in advance. A metal deposition film can also be formed via an anchor coat layer.

The thickness of the light reflecting layer is several hundred angstroms (Å) for a metal-deposited film, but it is necessary to consider the color, gloss, manufacturing cost, strength, flatness, etc. of the image formed on the heat-sensitive recording medium. The thickness may be determined as appropriate, and it is also possible to adopt a thickness that allows the base to be seen through.

Specific examples of the material of the protective layer 4 formed on the heat-sensitive recording layer 3 include polyethylene terephthalate, polyetherimide, polyetherketone, polyetheretherketone, polysulfone, polyphenylenesulfide, polyacrylate, and polyether. Examples thereof include sulfone, polycarbonate, polyethylene naphthalate, polyimide, and acrylic resin. Among these, an ultraviolet curable resin can be employed for the acrylic resin and the like.

An embodiment of a transfer sheet for a reversible thermosensitive recording medium according to the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 2A and 2B, the transfer sheet B of the reversible thermosensitive recording medium of the embodiment is peeled in a sheet shape (including a film-like shape) made of polyethylene terephthalate or the like. the release agent layer 6 made of a silicone resin on top of use base layer 5 is provided to constitute a release sheet B _1, made of a light transmissive resin to protect the surface after transfer thereon protection A layer 4 is laminated, a thermosensitive recording layer 3 made of a reversible thermosensitive recording material in which, for example, an organic low-molecular compound is blended in a resin base material is applied and dried, and an adhesive layer made of a hot melt resin is further provided thereon. 7 is a transfer sheet B of a reversible thermosensitive recording medium formed in 7.

Of the materials constituting the transfer sheet of the reversible thermosensitive recording medium of the present invention, the protective layer and the thermosensitive recording layer are the same as those described above, and other materials will be described below.

The release substrate layer 5 of the release sheet B ₁ is a sheet-like material such as a releasable film or paper, is easy to bend so that it can be easily peeled off and peeled, and is tough and resistant to tearing. Physical properties are required. When a plastic film is used as the release substrate layer 5,
The required mechanical properties are obtained by blending an appropriate amount of a plasticizer or a reinforcing agent into the base material.

Specific examples of the release substrate layer 5 include paper,
Cloth, polyester resin such as polyethylene terephthalate, polyethylene naphthalate, polypropylene, polystyrene, polycarbonate, polyvinyl chloride, polyethylene, polyamide, polyimide, polylactic acid, polysulfone, polyphenylene sulfide, polyetherimide, polyetheretherketone, polyethersulfone And so on.

The release agent layer 6 is formed by applying and drying a silicone resin or a fluorine resin. It is also possible to release sheet B ₁ which like impregnated with silicone oil or a fluorine resin is omitted release agent layer 6 to enhance the releasing property to the detachment base layer 5 described above.

The adhesive layer 7 is made of a thermoplastic resin having good heat adhesion, and for example, a vinyl chloride resin or a vinyl chloride-vinyl acetate copolymer resin can be used. In particular, it is preferable to use a heat-adhesive resin or a polyester resin containing a vinyl chloride-vinyl acetate-acrylic acid copolymer or a vinyl chloride-vinyl acetate-maleic acid copolymer as a main component. Further, in order to improve the thermal adhesiveness, it is also preferable to employ a thermal adhesive resin or a resin having a carboxyl group in which an isocyanate compound or a derivative thereof is blended as a crosslinking agent.

As shown in FIG. 2B, using the transfer sheet B of the reversible thermosensitive recording material of the above embodiment, a metal light reflecting surface of a card type reversible thermosensitive recording medium (commonly called a rewritable card). a main portion integrally laminated to M, by an adhesive layer 7 is heated and pressed in a metal light reflective surface M of the substrate, then peeling off the release sheet B _1, a metallic light reflecting surface M Of the thermosensitive recording layer 3, the protective layer 4, and the adhesive layer 7 (main part of the reversible thermosensitive recording medium) are adhered and fixed by thermocompression bonding.

[0049]

EXAMPLES AND COMPARATIVE EXAMPLES Example 1 Aluminum was deposited on the surface of a polyethylene terephthalate resin film substrate (188 μm thick), and the following reversible thermosensitive recording material was dissolved in tetrahydrofuran and applied thereon. ° C
After heating and drying for 5 minutes at 160 W / cm · 10 m / m
UV irradiation was performed at "in" to form a thermosensitive recording layer having a thickness of 10 [mu] m.

[Reversible thermosensitive recording material] Vinyl chloride-vinyl acetate copolymer (manufactured by Nissin Chemical Co., Ltd .: Solvain MF) 100 parts by weight Tetraethylene glycol diacrylate 50 parts by weight Photopolymerization initiator (manufactured by Ciba Geigy: Irgacure 184) 2 parts by weight Polyester plasticizer 25 parts by weight Stearyl stearate 40 parts by weight Eicosane diacid 8 parts by weight Corrosion inhibitor (benzothiazole-based compound having a concentration of 3%) (manufactured by Ciba-Geigy Corporation: IRGACOR 252LD) 7.5 parts by weight Coating a protective layer made of an epoxy acrylate UV curable resin on the formed heat-sensitive recording layer,
UV irradiation was performed at 160 W / cm · 10 m / min to form a protective layer having a layer thickness of 5 μm to obtain a sheet.

The following sheets (1), (2) and (3) were subjected to the following tests (1), (2) and (3) with respect to a sheet obtained by punching the obtained sheet into a card type (reversible thermosensitive recording medium of Example 1). Are shown in Table 1. (1) Recording characteristic (contrast) evaluation test A thermal head (0.
35 mJ / dot), the card was heated with a hot printing plate at 130 ° C. for 0.5 seconds to erase the print, and the reflection density on the surface of the reversible thermosensitive recording medium in this print / erase test was determined by Macbeth. Reflection densitometer (RD-918
When the reflection density was 0.4 or less, it was evaluated as a good printed state, and when it was 1.2 or more, it was evaluated as a good erased state (about 1.4 in the background), and there was no practical problem in contrast. , Good, problematic
Also shown in Table 1 with symbols of Δ and X. (2) Moisture resistance test The card-type thermal recording medium was left in a constant temperature bath at 40 ° C. and a humidity of 95% for 2 months, and thereafter the degree of corrosion of the light reflection layer (aluminum) was not corroded (（). The results were visually evaluated in three stages: marked (marked), corroded (marked with 著 し く), and remarkably corroded (marked with x). (3) Water resistance (immersion in water) test The card-type thermosensitive recording medium was immersed in 40 ° C fresh water for one month,
After that, the degree of corrosion of the light reflection layer (aluminum) was not corroded (marked with ○), corroded (marked with Δ), and significantly corroded (×
) Were visually evaluated in three stages, and the results are also shown in Table 1 by symbols.

[0052]

[Table 1]

Example 2 The procedure of Example 1 was repeated except that the composition of the reversible thermosensitive recording material was an ammonium salt of a benzothiazole compound (IRGACOR153, manufactured by Ciba-Geigy) in place of the corrosion inhibitor. In the same manner, a reversible thermosensitive recording medium was manufactured, and the above tests (1), (2), and (3) were performed. The results are shown in Table 1.

Example 3 A transfer sheet of a heat-sensitive recording material having the structure shown in FIG. 2A was manufactured and transferred to a metal light reflecting surface as shown in FIG. 2B. That is, FIG.
As shown in (a), the thickness of the release substrate layer 5 is 25 mm.
μm polyethylene terephthalate (PET) film, coated on one side with a coating composition obtained by mixing 100 parts by weight of alkyd melamine resin, 50 parts by weight of toluene and 50 parts by weight of ethyl acetate, and dried at 150 ° C. for 2 minutes Thus, a release agent layer 6 having a thickness of 2 μm was formed.

On top of this, 100 parts by weight of an epoxy acrylate-based UV-curable resin was added to isopropyl alcohol (IPA).
Diluted with 50 parts by weight and applied, 160W / cm / 10m
The coating was cured by irradiating with UV light at / min to form a protective layer having a thickness of 5 μm.

Then, a reversible thermosensitive recording material having the same composition as that of the reversible thermosensitive recording material used in Example 1 was dissolved in tetrahydrofuran and applied to the upper surface of the protective layer 3.
After heating and drying at 0 ° C. for 5 minutes, 160 W / cm · 10
Irradiation with ultraviolet light at m / min for curing, thickness 10 μm
Was formed.

Next, an adhesive layer 7 having the following composition was formed on the heat-sensitive recording layer 3. That is, a mixture obtained by adding 20 parts by weight of toluene and parts by weight of methyl ethyl ketone (MEK) to 40 parts by weight of a vinyl chloride-vinyl acetate-vinyl alcohol copolymer is applied, dried at 100 ° C. for 2 minutes, and adhered to 3 μm. Layer 7 was formed.

The transfer sheet obtained as described above is shown in FIG.
As shown in FIG. 13B, the light is applied to the light reflecting surface M made of metal.
The transfer was performed by pressing a rubber roll at 0 ° C., and then the release sheet was peeled off to complete the transfer of the reversible thermosensitive recording material.

The above tests (1), (2) and (3) were performed on the obtained reversible thermosensitive recording medium, and the results are shown in Table 1.

Comparative Example 1 A reversible thermosensitive recording medium was manufactured in exactly the same manner as in Example 1, except that a material in which a corrosion inhibitor was not used was used as the reversible thermosensitive recording material. On the other hand, (1), (2),
The test of (3) was performed, and these results are also shown in Table 1.

Comparative Example 2 In Example 1, an antioxidant (2,6-di-t-butyl-p-cresol) was used as the reversible thermosensitive recording material instead of the corrosion inhibitor in the composition. Except for this, a reversible thermosensitive recording medium was manufactured in exactly the same manner, and the above-mentioned (1), (2),
The test of (3) was performed, and these results are also shown in Table 1.

As is clear from the results shown in Table 1,
In Comparative Example 1, since the reversible thermosensitive recording layer containing no predetermined corrosion inhibitor was formed, the light-reflective layer made of vapor-deposited aluminum metal corroded due to poor moisture resistance and water resistance. Also in Comparative Example 2, when an antioxidant was added instead of the predetermined corrosion inhibitor, the light reflection layer made of vapor-deposited aluminum metal was poor due to poor moisture resistance and water resistance, and the image contrast was reduced.

On the other hand, the reversible thermosensitive recording media of Examples 1 to 3 in which a reversible thermosensitive recording layer containing a predetermined corrosion inhibitor was formed, had good moisture resistance and water resistance, and were made of vapor-deposited aluminum metal. The light reflection layer did not corrode, and the contrast of the image was maintained relatively clearly.

[0064]

As described above, the invention relating to the reversible thermosensitive recording medium according to the present invention is characterized in that the reversible thermosensitive recording layer contains an organic metal corrosion inhibitor so that the reversible thermosensitive recording layer is reversible with the metal light reflection layer. Since a moisture-resistant transparent film is formed at the interface of the heat-sensitive recording layer, the image contrast does not decrease even under high humidity conditions in the use state of the heat-sensitive recording medium, and the reversibility is excellent in moisture resistance and water resistance. There is an advantage that it becomes a thermal recording medium.

Further, in the invention relating to the transfer sheet of the reversible thermosensitive recording medium of the present invention, the reversible thermosensitive recording layer contains an organic metal corrosion inhibitor, and the metal light reflection layer and the reversible thermosensitive recording layer Since a moisture-resistant transparent film is formed on the interface, the image contrast does not decrease when the transferred heat-sensitive recording material is used, and a reversible heat-sensitive recording medium that is excellent in moisture resistance and water resistance is made of a metal light reflecting surface. There is the advantage that it can be transferred onto.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an enlarged part of a reversible thermosensitive recording medium.

FIG. 2A is an enlarged cross-sectional view showing a part of a transfer sheet of a reversible thermosensitive recording medium. FIG. 2B is an enlarged cross-sectional view showing a transfer state of the transfer sheet of a reversible thermosensitive recording medium.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Film base material 2 Light reflection layer 3 Thermal recording layer 4 Protective layer 5 Release base layer 6 Release agent layer 7 Adhesive layer A Reversible thermosensitive recording medium B Transfer sheet B ₁ Release sheet M Light reflection surface

Claims (4)

[Claims] 1. A laminate comprising a reversible thermosensitive recording layer and a metal light-reflecting layer on the back side of the reversible thermosensitive recording layer. A reversible thermosensitive recording medium capable of displaying and erasing, wherein the reversible thermosensitive recording layer contains an organic metal corrosion inhibitor. 2. An organic metal corrosion inhibitor, wherein the organic metal corrosion inhibitor is an addition compound of a ketocarboxylic acid compound and ethylmorpholine, an addition compound of a ketocarboxylic acid compound and zirconium oxide, a benzothiazole-based compound. The reversible thermosensitive recording medium according to claim 1, which is at least one organic metal corrosion inhibitor selected from the group consisting of a compound and an ammonium salt of a benzothiazole compound. 3. A transfer thermosensitive recording medium comprising a reversible thermosensitive recording layer and a metal light-reflective layer laminated on the back side thereof, and the transfer thermosensitive recording medium is peelable from a release sheet. A transfer sheet for a reversible thermosensitive recording medium, wherein the reversible thermosensitive recording layer contains an organic metal corrosion inhibitor. 4. An organic metal corrosion inhibitor comprising an addition compound of a ketocarboxylic acid compound and ethylmorpholine, an addition compound of a ketocarboxylic acid compound and zirconium oxide, a benzothiazole compound and an ammonium salt of a benzothiazole compound. The transfer sheet for a reversible thermosensitive recording medium according to claim 3, which is an organic metal corrosion inhibitor comprising one or more compounds selected from the group consisting of: