JPH04351588A - Heat-sensitive recording medium and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal recording medium, and more particularly to a thermal recording medium that allows thermal recording using different recording methods on both sides. The present invention can be effectively applied to a magnetic card, such as a prepaid card such as a telephone card, on which numbers or the like corresponding to the magnetically recorded contents are printed so that the magnetically recorded contents can be visually recognized.

0002

BACKGROUND OF THE INVENTION Magnetic cards are widely used as convenient and useful cards to carry. The card has a magnetic recording layer formed in a desired area on the surface of a card base material of an appropriate thickness.

[0003] By the way, it is not possible to visually check the magnetic recording information of magnetic cards such as usage history and balance amount, and for this reason, prepaid magnetic cards display the balance through punch holes etc. as a guide, but there is no clear way to do so. Since the balance is not displayed, if the balance is insufficient, a situation arises in which it is necessary to replenish the balance with cash or a magnetic card. As a measure to avoid such a situation, it is sometimes required to print the usage history and balance amount on the surface of the card.

[0004] Furthermore, it is common to print a desired design on the surface of the magnetic card opposite to the magnetic recording layer side, and conventionally, card manufacturers have manufactured and sold cards with the design attached. There is.

However, in recent years, magnetic card users have
It has become increasingly desirable to add a pattern with a desired design at the time of purchase or after purchase. Such a pattern can be easily provided by printing a pattern created using a word processor or a personal computer using a printer.

[0006] As described above, it is desirable to perform two types of visible recording (ie, the above-mentioned printing and the above-mentioned pattern printing) on magnetic cards. One of these (printing) may be in a single color, while the other (pattern printing) is desired to be in color.

Therefore, in order to perform two different types of visible recording as in the above-mentioned magnetic cards, the present invention is capable of thermal recording using the first type of method for the first purpose, and also has a second method. It is an object of the present invention to provide a thermal recording medium capable of thermal recording by a second type of method for the purpose of.

[0008]

[Means for Solving the Problems] According to the present invention, in order to achieve the above object, a heat-sensitive coloring layer is provided on the first surface side of the base material layer, and the surface on the second surface side of the base material layer is provided. Provided is a thermal recording medium characterized in that it has an image receiving layer for thermal transfer recording. Here, a magnetic recording layer can be provided between the base layer and the thermosensitive coloring layer, and a concealing layer can be provided between the magnetic recording layer and the thermosensitive coloring layer.

According to the present invention, in order to achieve the above object, the base material layer has a metal thin film layer on the first surface side and a metal particle receiving layer in contact with the metal thin film layer. A thermal recording medium is provided, characterized in that it has an image receiving layer for thermal transfer recording on the second surface side of the layer. Here, a magnetic recording layer can be provided between the base material layer and the metal thin film layer.

Further, according to the present invention, in the above method for producing a thermal recording medium, after forming an image receiving layer on the second surface side of the base layer, the thermosensitive coloring layer or metal layer on the first surface side of the base layer is formed. A method of manufacturing a thermal recording medium is provided, the method comprising forming a thin film layer.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings. In the following examples, an example is shown in which the thermal recording medium is a magnetic card having a magnetic recording layer.

FIG. 1 is a schematic sectional view showing a first embodiment of a thermal recording medium according to the present invention. In this figure, a magnetic recording layer 4 is formed on the first surface (lower surface) of the base material layer 2, a concealing layer 6 is formed on the magnetic recording layer, and the concealing layer A thermosensitive coloring layer 8 is formed thereon, a resin thin film layer 10 is formed on the thermosensitive coloring layer, and a protective layer 12 is formed on the resin thin film layer. Further, an image receiving layer 14 is formed on the second surface (upper surface) of the base material layer 2.

As the base material layer 2, for example, a synthetic resin sheet such as polyethylene terephthalate, epoxy resin, polyvinyl chloride, polycarbonate, etc., synthetic paper, etc. can be used. The thickness of the base material layer 2 is, for example, 1
It is about 00 to 300 μm.

As the magnetic recording layer 4, those generally used as magnetic recording layers in conventional magnetic recording media of this type can be used. For example, as a magnetic material, Ba-ferrite, Sr-ferrite, Co-coated γ-F with a particle size of 10 μm or less, preferably 0.01 to 5 μm
e2O3, γ-Fe2O3, needle iron powder, CrO
2, polyester resin, alkyd resin, vinyl resin, commonly used as binder resin,
A polyurethane resin or a mixed resin thereof can be used. The mixing ratio of the binder resin and the magnetic material is appropriately set in consideration of the adhesion with the base layer 2, the strength of the coating film, the voltage detected by the magnetic head, etc., and is, for example, 1/1 in terms of weight ratio.
A range of 1/10 to 1/10 is possible, preferably 1/2 to 1
/8 is appropriate. The thickness of the magnetic recording layer 4 is, for example, about 5 to 20 μm.

The hiding layer 6 has a color (for example, white) that visually hides the color of the magnetic recording layer 4 and provides sufficient contrast to the color of the thermosensitive coloring layer 8. Further, as the hiding layer 6, a material is used that is stable under thermosensitive recording conditions, has sufficient durability even if thin, and can prevent the constituent materials of the magnetic recording layer 4 from transferring to the thermosensitive coloring layer 8. is preferable. As such heat-resistant materials, thermosetting resins such as polyamide resins, epoxy resins, acrylic resins, phenol resins, unsaturated polyester resins, polyurethane resins, diallyl phthalate resins, etc. can be used, and these can be given hiding properties. Pigments such as Al, Sn, Pb, Zn, Cu, Ag, Cu-Z
Appropriate amounts of metals such as n and metal oxides such as AlO2 and TiO2 are added. The hiding layer 6 may include a non-magnetic metal layer such as Al, Sn, Pb, in addition to the thermosetting resin as described above.
, Ag, Bi, Se, Te, In, Cd, or layers of oxides of these metals can also be used. The thickness of the concealing layer 6 is, for example, about 0.5 to 2 μm.

The thermosensitive coloring layer 8 may include leuco dye,
A material containing an acidic color developer and a binder resin can be used.

The leuco dye in the heat-sensitive coloring layer 8 includes triphenylmethane-based dyes such as crystal violet lactone and malachite green lactone;
Fluorane-based materials such as 2-benzo-6-diethylaminofluorane, auramine-based materials such as N-benzoyl auramine, other phenothiazine-based materials, spiropyran-based materials, etc. can be used.

As the acidic color developer in the heat-sensitive color forming layer 8, a compound having a phenolic hydroxyl group, that is, a phenolic compound can be used. Examples of such substances include phenol, o-cresol, p-cresol, p-ethylphenol, t-butylphenol,
, 6-di-t-butyl-4-methylphenol, nonylphenol, dodecylphenol, styrenated phenol, 2,2'-methylene-bis(4-methyl-6-t-
butylphenol), α-naphthol, β-naphthol, hydroquinone monomethyl ether, guaiacol,
Eugenol, p-chlorophenol, p-bromophenol, o-chlorophenol, o-bromophenol, 2,4,6-trichlorophenol, o-phenylphenol, p-phenylphenol, p-(p-chlorophenyl)phenol, o-(o-chlorophenyl)phenol, salicylic acid, ethyl p-oxybenzoate, p
-propyl oxybenzoate, octyl p-oxybenzoate, dodecyl p-oxybenzoate, catechol, hydroquinone, resorcinol, 3-methylcatechol, 3-isopropylcatechol, pt-butylcatechol, 2,
5-di-t-butylhydroquinone, 4,4'-methylene diphenol, bisphenol A, 1,2-dioxynaphthalene, 2,3-dioxynaphthalene, chlorocatechol, bromocatechol, 2,4-dihydroxybenzophenone, Phenolphthalein, o-cresolphthalein, methyl protocatechuate, ethyl protocatechuate, propyl protocatechuate, octyl protocatechuate, dodecyl protocatechuate, pyrogallol, oxyhydroquinone, phloroglucin, 2,4
, 6-trioxymethylbenzene, 2,3,4-trioxyethylbenzene, methyl gallate, ethyl gallate, propyl gallate, butyl gallate, hexyl gallate, octyl gallate, dodecyl gallate, cetyl gallate , stearyl gallate, 2,3,5-trioxynaphthalene, tannic acid, phenolic resin, and the like.

The binder resin in the heat-sensitive coloring layer 8 includes alkyd resin, vinyl chloride resin, urethane resin, xylene resin, phenol resin, coumaron resin,
Vinyl toluene resin, terpene resin, vinyl toluene/
Oil-soluble resins such as butadiene copolymer resin, vinyl toluene/acrylate copolymer resin, polyvinyl alcohol resin, methyl cellulose resin, hydroxyethyl cellulose resin, carboxymethyl cellulose resin, methyl vinyl ether/maleic anhydride copolymer resin, polyacrylic acid Water-soluble resins such as resin, gelatin, and gum arabic can be used.

In the heat-sensitive coloring layer, the ratio of the leuco dye to the acidic color developer is, for example, 1:0.5 to 1:3 (equivalent), and the ratio of the binder resin to (leuco dye + acidic color developer) is, for example, 1:0.5 to 1:3 (equivalent). The ratio is, for example, 1:0.1 to 1:3 (by weight).

The thickness of the heat-sensitive coloring layer 8 is, for example, 2.
It is about 10 μm.

The resin thin film layer 10 is similar to the thermosensitive coloring layer 6.
It is interposed to improve the adhesion between the protective layer 12 and the protective layer 12, and for example, polyester resin, vinyl chloride/vinyl acetate resin, polyurethane resin, alkyd resin, cellulose resin, etc. can be used. The material for the resin thin film layer is appropriately selected in consideration of the properties of the binder resin used in the thermosensitive coloring layer and the properties of the binder resin used in the protective layer. The thickness of the resin thin film layer 10 is, for example, about 0.5 to 8 μm.

The protective layer 12 may be one that has been conventionally used as a protective layer in this type of magnetic recording medium;
For example, cellulose resin, urethane resin, polyester resin, vinyl resin, epoxy resin, acrylic resin, etc. can be used. To these resins, phthalate esters, fatty acid esters, orthophosphoric esters, etc. can be added as plasticizers, and oleylamide, stearylamide, etc. can be added as lubricants.
Silicone etc. can be added. In addition, in order to reduce the amount of solvent used, an ultraviolet curable resin or an electron beam curable resin can be used, and as the ultraviolet curable resin, acrylic, epoxy, polyester, etc. can be used. . The thickness of the protective layer 12 is, for example, 0.
It is about 5 to 5 μm.

The image receiving layer 14 is a layer for printing a desired image by thermal transfer via an ink ribbon having a thermal transfer ink layer containing a sublimable dye, and is a layer for printing a desired image by thermal transfer using inks of different colors. , color printing of desired colors can be realized. Materials for this image-receiving layer include polyester resin, polyacrylic acid ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, vinyl toluene acrylate resin, polyurethane resin, polyamide resin, urea resin, polycaprolactane resin, and styrene resin. type resins, vinyl chloride resins, vinyl chloride-vinyl acetate copolymer resins, polyacrylonitrile resins, and mixtures thereof. These resins may contain extender pigments such as silica, calcium carbonate, titanium oxide, zinc oxide, and other additives, if necessary. The image receiving layer 14
The thickness is, for example, about 1 to 30 μm.

In the magnetic recording/reproduction of the magnetic card of this embodiment, the magnetic head is brought into contact with the protective layer 12, but in order to avoid increasing the distance between the magnetic head and the magnetic recording layer 4, the shielding layer 6 is The total thickness up to the protective layer 12 is preferably 10 μm or less.

FIG. 2 is a schematic cross-sectional view showing a second embodiment of the thermal recording medium according to the present invention. In this figure, the same members as in FIG. 1 are given the same reference numerals. In this embodiment, an undercoat layer 5 is formed on the magnetic recording layer 4, a metal thin film layer 7 is formed on the undercoat layer, and an overcoat layer 9 is formed on the metal thin film layer. A resin thin film layer 10' is formed on the upper layer, and a protective layer 12 is formed on the resin thin film layer.

The metal thin film layer 7 hides the magnetic recording layer 4 and is used as a heat-sensitive writing recording film. Materials constituting the metal thin film layer include, for example, Sn, Bi, and S.
Low melting point metals such as e, Te, Zn, In, and Pb-Sn can be used. The thickness of the metal thin film layer 8 is, for example, about 0.03 to 0.2 μm.

The undercoat layer 5 is provided to improve the writing/recording characteristics (sensitizing effect) of the metal thin film layer 7 and to improve the adhesion of the metal thin film layer 7 to the magnetic recording layer 4. Examples of such materials include self-oxidizing resins such as nitrocellulose resins, acrylic resins, polyester resins, vinyl chloride resins, vinyl acetate resins, polystyrene resins, and polybutyral resins. Plastic resin can be used. By roughening the surface of the undercoat layer 5, the background color of the metal thin film layer 7 formed thereon can be brought closer to white by uniform diffuse reflection, making it easier to see. In order to roughen the surface of the undercoat layer 5 in this way, when forming the undercoat layer, fine particles such as melamine/formaldehyde condensate, polyimide resin powder, low molecular weight tetrafluoride, etc. are added to the undercoat layer material. Ethylene resin powder, calcium stearate, tin stearate, polystyrene latex, bentonite, wollastonite, talc, aluminum silicate, sericite, aluminum silicate, kaolin clay, white carbon, calcium carbonate, chalk, slaked lime, dolomite powder, magnesium carbonate , barium sulfate, etc., may be contained in an amount of 50 parts by weight or less, preferably 25 parts by weight or less, per 100 parts by weight of the resin. The thickness of the undercoat layer 6 is, for example, about 0.5 to 8 μm.

The above-mentioned upper layer 9 is provided for the purpose of improving the writing/recording characteristics (sensitizing effect) of the metal thin film layer 7,
As its material, the same material as the undercoat layer can be used.

[0030] The resin thin film layer 10' is similar to the upper coating layer 9.
It is interposed to improve the adhesion between the protective layer 12 and the protective layer 12, and the same material as the resin thin film layer 10 can be used as the material. still,
The material of the resin thin film layer 10' is appropriately selected in consideration of the characteristics of the resin used for the upper layer 9 and the characteristics of the binder resin used for the protective layer 12.

Note that during magnetic recording and reproducing of the magnetic card of this embodiment, the magnetic head is brought into contact with the protective layer 12, but in order not to increase the distance between the magnetic head and the magnetic recording layer 4, the undercoat layer 5 is It is preferable that the total thickness from the protective layer 12 to the protective layer 12 be 10 μm or less.

FIG. 3 is a schematic cross-sectional view for explaining a method of printing on the heat-sensitive coloring layer 8 in the magnetic card of the first embodiment. As shown in the figure, when the thermal head H is brought into contact with the protective layer 12 and scanned in the direction of the arrow, and the heating element of the head H is caused to generate heat at appropriate times, the heat-sensitive coloring layer 8 develops color due to the heat generation, and recording is performed. Ru. Since the heat-sensitive coloring layer 8 remains in the area not heated by the heat generated by the head, the area exhibits the white color of the hiding layer 6, so that printing with sufficient contrast is achieved.

FIG. 4 is a schematic cross-sectional view for explaining a method of writing a visible pattern on the image receiving layer 14 in the magnetic cards of the first and second embodiments. As shown in the figure, when the thermal head H is brought into contact with the image receiving layer 14 via the ink ribbon R and scanned in the direction of the arrow, and the heat generating element of the head H is caused to generate heat at appropriate times, the ink is dissolved by the heat generated. A dye or pigment is deposited on the image receiving layer 14. Furthermore, a color pattern is recorded by overprinting using ink ribbons of different colors.

FIG. 5 is a schematic cross-sectional view for explaining the method of printing on the metal thin film layer 7 in the magnetic card of the second embodiment. As shown in the figure, when the thermal head H is brought into contact with the protective layer 12 and scanned in the direction of the arrow, and the heating element of the head H is made to generate heat at appropriate times, the heat generated causes the undercoat layer 5, the metal thin film layer 7, and the upper The pulling layer 9 melts, and at this time,
Since the metal thin film layer 7 is thin, it becomes fine particles and disperses within the undercoat layer 5 and the overcoat layer 9 due to surface tension when melted. In the areas where the metal thin film layer constituent material is dispersed in this way, the metal thin film layer is in a destroyed state, and after the head H has passed, the undercoat layer 5 and the top coat layer 9 solidify in this state to fix the recording. transformation is done. The parts that are not heated by the head heat generation have a white color because the metal thin film layer 7 remains as they are, but the parts that have been heated by the head heat have a blackish color of the magnetic recording layer 4, and are therefore sufficiently A visible pattern of contrast is formed. Although there are fine metal particles dispersed in the subbing layer 5 and the overcoating layer 9 in the destroyed portions of the metal thin film layer 7, the amount thereof is so small that visual inspection of the magnetic recording layer 4 is not hindered.

The printing on the thermosensitive coloring layer 6 or the metal thin film layer 7 in the above two embodiments is monochrome, and is effectively applied to printing the card usage record (date, payment amount, etc.) and balance details. In other words, each time a magnetic card is used, the balance amount recorded in the magnetic recording layer 4 is corrected, but by thermally printing the details on the card, the user can always check the contents of the card. You can know. This printing is done in a device on the magnetic card system side.

Furthermore, the image receiving layer 1 in the above two embodiments
4 can be used by the card user to print a desired design.

In the magnetic card of this embodiment, the magnetic recording layer 4
Information such as the ticket type, usage record, and balance amount is recorded on the card, and the magnetic information is recorded and reproduced using a normal method.

In manufacturing the magnetic card of the above embodiment, first, the magnetic recording layer 4 is formed on the first surface side of the base layer 2,
Next, an image receiving layer 14 is formed on the second surface side of the base material layer 2, and then a concealing layer 6 is formed on the magnetic recording layer 4 on the first surface side of the base material layer 2.
Alternatively, it is preferable to form the undercoat layer 7 to the protective layer 12. That is, by doing so, the thermosensitive coloring layer 8 does not develop color due to the heat generated during the formation of the image receiving layer 14, and the metal thin film layer 7 is not melted and destroyed, and a good magnetic card can be obtained at a high yield.

[0039]

According to the present invention as described above, it is possible to perform thermal recording using the first type of method for the first purpose, and also to perform thermal recording using the second type of method for the second purpose. A thermal recording medium capable of thermal recording is provided. Further, according to the present invention, such a thermal recording medium can be manufactured with a good yield.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing a first embodiment of a thermal recording medium according to the present invention.

FIG. 2 is a schematic cross-sectional view showing a second embodiment of the thermal recording medium according to the present invention.

FIG. 3: Thermosensitive coloring layer 8 in the magnetic card of the first embodiment
FIG.

FIG. 4 is a schematic cross-sectional view for explaining a method of writing a visible pattern on the image receiving layer 14 in the magnetic cards of the first embodiment and the second embodiment.

FIG. 5: Metal thin film layer 7 in the magnetic card of the second embodiment.
FIG.

[Explanation of symbols]

2 Base material layer 4 Magnetic recording layer 5 Undercoat layer 6 Hidden layer 7 Metal thin film layer 8 Thermosensitive coloring layer 9 Top layer 10,10' resin thin film layer 12 Protective layer 14 Image receiving layer

Claims (6)

[Claims] 1. A thermal recording device, characterized in that it has a thermosensitive coloring layer on the first side of the base layer, and an image receiving layer for thermal transfer recording on the second side of the base layer. Medium. 2. The thermal recording medium according to claim 1, wherein a magnetic recording layer is provided between the base layer and the thermosensitive coloring layer. 3. The thermal recording medium according to claim 2, wherein a hiding layer is provided between the magnetic recording layer and the thermosensitive coloring layer. 4. The base material layer has a metal thin film layer on the first surface side and a metal particle receiving layer in contact with the metal thin film layer, and the second surface side of the base material layer has a metal thin film layer for thermal transfer recording. A thermal recording medium characterized by having an image-receiving layer. 5. The thermal recording medium according to claim 4, wherein a magnetic recording layer is provided between the base layer and the metal thin film layer. 6. In the method for producing a thermal recording medium according to claim 1 or 4, after forming the image receiving layer on the second surface side of the base layer, the thermal recording medium on the first surface side of the base layer is formed. A method for producing a thermal recording medium, comprising forming a coloring layer or a metal thin film layer.