JPH1011807A - Optical card recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical card recording medium which prevents the influences of the residual solvent contained in printing layers of visible information, etc., on an org. dye recording layer. SOLUTION: A surface on which the preformat 13 of a substrate 1 is formed, is provided with the recording layer 2 consisting of org. dye and this recording layer 2 is provided thereon with a protective layer 4 via an adhesive layer 3. The recording layer side of this protective layer 4 is provided with the porous light concealing printing layer 54 and the internal printing layer 55a of visible information. The outer side of the protective layer 4 is provided with the external porous printing layer 55b of the visibe information. These porous printing layers are formed by printing with printing ink contg. a porous resin of a polyester system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical card recording medium provided with a printed layer of visible information.

[0002]

2. Description of the Related Art In recent years, card-shaped optical recording media have been commercialized as optical cards. In addition to the optical recording data, it is essential for the optical card to record personal data in the same manner as a conventional credit card, bank card, and the like. The information is written on the card as visible information. Generally, personal information is printed and recorded for each optical card using a thermal transfer printer, and common information is provided on the card surface by screen printing, offset printing, gravure printing, or the like.

On the other hand, inexpensive and low-toxic organic dyes are being put to practical use as recording materials for optical recording media. As an optical card recording medium using an organic dye for the recording layer, FIG.
And a configuration as shown in FIG. 5 are known.

FIG. 4 is a schematic sectional view showing an example of a conventional optical card recording medium. In FIG. 4, the optical card recording medium is provided with a recording layer 2 made of, for example, an organic dye on the preformatted surface of a substrate 1 having an irregular preformat formed on the surface. Adhesive layer 3
A protective layer 4 is provided through the protective layer 4 to protect the recording layer 2, while a hard coat layer 6 is provided on the outer surface of the substrate 1 to protect the substrate 1,
On the recording layer side of the protective layer 4, an internal printing layer 51 which is a light shielding layer is provided.
And a visible information print 53, and an external print layer 52 of visible information is provided outside the protective layer 4.

FIG. 5 is a schematic sectional view showing another example of a conventional optical card recording medium. The optical card recording medium shown in FIG. 5 has a visible information print 53 on the opposite side of the protective layer 4 from the recording layer side.
Is provided thereon, and an inner printing layer 51 as a light shielding layer and an outer printing layer 52 for visible information are sequentially provided thereon, and an overcoat layer 8 having a magnetic stripe 7 embedded thereon is further provided thereon.
Is provided.

[0006]

However, in the conventional optical card recording medium having the structure shown in FIGS. 4 and 5, the external printing layer 52 for visible information, the visible information printing 53 and the optical information There is a problem that the residual solvent contained in the inner printing layer 51 for concealing vaporizes with time or moves and diffuses inside the adhesive layer 3 to reach the recording layer, thereby lowering the reflectance of the recording layer. Was.

SUMMARY OF THE INVENTION The present invention has been made to solve such problems of the prior art, and it is intended to prevent the influence of a residual solvent contained in a printing layer such as visible information on the recording layer, and to reduce the influence of the recording layer. It is an object of the present invention to provide an optical card recording medium in which a change in reflectance is minimized.

[0008]

That is, the present invention relates to a card-shaped recording medium having a recording layer comprising an organic dye.
An optical card recording medium having a porous printing layer formed of a printing ink containing a polyester-based porous resin.

In the present invention, the porous printing layer comprises:
It includes a porous printed layer for visible information and a porous printed layer for concealing light.

On the recording layer, a protective layer for protecting the recording layer via an adhesive layer is provided, and the porous printing layer is provided on at least one of both surfaces of the protective layer. For example, even when the porous printing layer is provided on the recording layer side of the protective layer, it is possible to prevent the residual solvent contained in the printing layer from affecting the recording layer.

In the optical card recording medium of the present invention, the amount of the solvent remaining in the porous print layer is extremely small, and is 100 ppm or less based on the ink.

The polyester porous resin used for the ink containing the polyester porous resin is preferably made of a polyester resin containing fine particles of an inorganic substance or an organic substance having a particle size of 0.5 to 3 μm.

[0013]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical card recording medium having a recording layer comprising an organic dye, wherein a printing ink containing a polyester-based porous resin is used as a printing ink for forming a visible information and concealment printing layer. And forming a porous print layer by using it. By using this porous printing layer, it becomes possible to minimize the diffusion of the residual solvent of the printing ink into the recording layer. That is, since the porous printing layer formed by the printing ink becomes porous, the diffusion rate of the solvent contained in the printing ink increases, and the solvent can be sufficiently removed in the heating and drying step of the printing ink. Becomes As a result, finally, in the optical card recording medium, the remaining amount of the solvent of the printing ink contained in the porous printing layer can be reduced to 100 ppm or less. It is difficult to change.

FIG. 1 is a schematic sectional view showing an example of the optical card recording medium of the present invention. In FIG. 1, an optical card recording medium according to the present invention has a preformat 1 having an uneven surface.
The recording layer 2 made of an organic dye is provided on the surface of the substrate 1 on which the preformat 13 is formed, on which the recording layer 2 is formed.
A protective layer 4 is provided on the recording medium 2 with an adhesive layer 3 interposed therebetween to protect the recording layer 2, while a hard coat layer 6 is provided on the outer surface of the substrate 1 to protect the substrate 1. Is provided with a porous light concealed print layer 54 and an internal porous print layer 55a for visible information, and an external porous print layer 55b for visible information is provided outside the protective layer 4.

In FIG. 1, the porous print layer includes a porous light concealment print layer 54 of a light concealment layer and an internal porous print layer 55a.
And an outer porous printing layer 55b, all of which are provided by printing with a printing ink containing a polyester-based porous resin.

FIG. 2 is a schematic sectional view showing another example of the optical card recording medium of the present invention. FIG. 2 shows a case where the protective layer has a light concealing property, and a light concealing protective layer 41 is used. In this case, it is not necessary to provide a porous light concealing printing layer by printing as shown in FIG.

FIG. 3 is a process chart showing an example of a method for manufacturing an optical card recording medium according to the present invention. In the method for producing an optical card recording medium of the present invention, first, a porous light-shielding printing layer 54 is formed on one surface of a protective layer 4 made of a protective substrate by printing with a printing ink containing a polyester-based porous resin, An internal porous print layer 55a of visible information is similarly provided thereon by printing, and an external porous print layer 55b of similarly visible information is provided on the other surface of the protective layer 4 by printing. To dry the printed layer. (See FIG. 2 (a))

Next, a solid adhesive layer 3 is prepared.
(See FIG. 2 (b)) Next, the recording layer 2 made of an organic dye is provided on the surface of the substrate 1 on which the preformat 13 is formed, and the hard coat layer 6 is formed. Is provided on the outer surface of the substrate 1. (See FIG. 2 (c).) An optical card recording medium can be obtained by laminating the protective layer 4 on the recording layer 2 of the substrate 1 via the adhesive layer 3. (See Fig. 2 (d))

In the present invention, the resin constituting the printing ink for forming the porous printing layer is preferably a polyester porous resin. In order to make the polyester resin porous, (1) a matting agent is added to the polyester resin in an amount of 2 to 10% by weight. (2) Urethane-based particle size of 0.5 to 3 in polyester resin
1 to 20 wt% of micron particles are added. (3) A low boiling solvent is added in an amount of 1 to 5% to the solvent of the printing ink. Such a method can be used.

The content of the polyester-based porous resin contained in the printing ink is 1 to 10% by weight, preferably 1 to 5%.
wt% is desirable. If it is less than 1 wt%, the evaporation of the solvent is not promoted, and if it exceeds 10 wt%, the composition of the resin constituting the ink is undesirably separated (layer separation) or cohesive failure.

Other components contained in the printing ink include a pigment, a solvent, and a leveling agent.

The solvent is not particularly limited, and a commonly used organic solvent is used, and examples thereof include ethanol, diacetone alcohol, methylcell solvable, and a mixture thereof. The content of the solvent is 10 to 50 wt%,
Preferably, the content is 30 to 50% by weight.

In the present invention, as a printing method for forming a porous printing layer using a printing ink, silk screen printing, gravure printing, offset printing, and spin coating are used.

As the substrate 1 on which the preformat is formed, an optically transparent plastic material such as polycarbonate, polymethyl methacrylate, polyolefin, and other polymer alloys can be used. The preformat 13 is provided on the substrate by injection molding, RG molding, compression molding, casting molding, or the like. Further, an ultraviolet curable resin layer may be provided on a substrate and formed by a so-called 2P method. It is preferable to provide a hard coat layer 6 on the surface of the substrate opposite to the surface on which the pre-grooves are formed, in order to prevent the occurrence of the substrate scratches.

For the recording layer 2, an optical recording material comprising a generally known organic dye is used. For example, anthraquinone derivatives (especially those having an indanthrene skeleton),
Dioxazine compounds and derivatives thereof, triphenodithiazine compounds, phenanthrene derivatives, cyanine compounds, merocyanine compounds, pyrylium compounds, xanthene compounds, triphenylmethane compounds, croconium dyes, azo dyes, crocones, azines, indigoids , Polymethine dye, azulene dye, squarium dye, cyanine dye having a polymethine chain,
Organic dye substances such as tetraphenylcyanine dyes are exemplified.

The thickness of the recording layer is preferably in the range of 400 to 1200 °, but is usually set to a thickness at which the reflectance is maximized by the correlation between the thickness of the recording layer and the reflectance. The recording layer containing these organic dyes may contain a stabilizer such as an infrared absorber for the purpose of improving light resistance.

The materials to be blended as the light stabilizer include:
For example, substances described in JP-A-60-163245 and JP-A-60-236131, or the following formulas (1) and (2)

[0028]

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(Wherein R is a hydrogen atom, a lower alkyl group,
X is an anion, either ClO ₄ ⁻ , SbF ₆ ⁻ or I ⁻ , and A is

[0030]

Embedded image And n is an integer. ).

Further, in the skeletons of the above formulas (1) and (2), a substance in which R, which is a substituent of N, has a methoxy group, a propenyl group, or a cyclocyclic group can also be used.

Further, metal complexes represented by the following formulas (3) to (7) can be used.

[0033]

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[0034]

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(However, R ₁ to R ₄ may be the same or different, each represents a substituted or unsubstituted alkyl group, aryl group or amino group, and R ₅ to R ₈ are the same or different. Each represents a hydrogen atom, a halogen atom or a substituted or unsubstituted alkyl group or an amino group, and M represents Ni, Co, Mn, C
represents a transition metal selected from u, Pd and Pt)

In the present invention, the content of the light stabilizer contained in the recording layer 2 is usually 5 to the content of the organic dye.
The range is preferably from 50 to 50% by weight, preferably from 10 to 30% by weight.

The adhesive layer 3 used in the present invention may be any as long as it does not change the optical constants (reflectance, transmittance, spectrum) of the recording layer. However, the adhesive having a low melting point of 70 ° C. or less, or a softening point of 6 ° C.
Lower than 5 ° C, melt flow rate is 10g / 1
A recording time of 0 min or longer is not preferred because the storage durability of the recording layer is reduced.

In general, hot melt adhesives such as ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic ester copolymer,
Ethylene-acrylic acid-polypropylene terpolymer,
A hot-melt adhesive containing ethylene-acrylic acid ester-maleic anhydride copolymer or the like as a main component, or a thermosetting or room-temperature curable material containing silicone as a main component can be used.

The material for forming the protective layer 4 in the present invention is polymethyl methacrylate, polycarbonate,
Resins such as polyvinyl chloride, polyethylene terephthalate, polystyrene, and polysulfone can be used.

[0040]

EXAMPLES The present invention will be specifically described below with reference to examples.

Example 1 A pre-formed optical card substrate made of polymethyl methacrylate having a thickness of 0.4 mm, a length of 54 mm and a width of 85 mm in which a stripe-shaped pre-groove having a width of 3 μm and a pitch of 12 μm was formed on one surface by casting. An ultraviolet-curable resin (trade name: Unidick 17-824-9, manufactured by Dainippon Ink and Chemicals, Inc.) is applied to the surface on which the groove is not formed, and then irradiated with ultraviolet light to form a hard coat having a thickness of 3 to 4 μm. Was formed.

Further, a polymethine dye represented by the following structural formula (I-1) and a stabilizer represented by the following structural formula (I-2) are provided on the surface of the substrate on which the pregroove is formed at a weight ratio of 3: The recording layer was formed to a thickness of 900 ° by a solvent coating method.

[0043]

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[0044]

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Next, on the recording layer made of an organic dye, a vertical 54
Adhesive sheet (manufactured by Sumitomo Chemical Co., Ltd., trade name: WD201, MMA (methyl methacrylate) content: 10 wt%, melt flow rate 2) made of 100 wt% of an ethylene-methyl methacrylate copolymer having a thickness of 50 mm, a width of 85 mm and a thickness of 50 μm.
g / 10 min, Vicat softening temperature 75 ° C, surface tension 32d
yn / cm), a protective material having a thickness of 0.3 mm was laminated, and pressed and bonded with a heating roll having a surface temperature of 130 ° C to produce an optical card.

The protective material was prepared as shown in FIG. A logo print 55b and a print layer (concealing layer) 54 of a light-shielding paint were formed on one surface of a PMMA plate having a thickness of 0.25 mm by screen printing. The printing ink used was a polyester resin in which a matting agent was added at 2 wt% and TiO ₂ particles were added at 10 wt%. The heat treatment after printing of the printing ink was performed at 95 ° C. for 1.5 hours.

Example 2 In the same manner as in Example 1 except that a polycarbonate substrate having a pre-groove formed by roller grooving was used in place of the substrate of Example 1, and polycarbonate having a thickness of 0.25 mm was used as a base material of a protective material. An optical card recording medium was created. Heat treatment after printing of printing ink is 110
C. for 1 hour.

Example 3 An optical card recording medium was prepared in the same manner as in Example 2, except that a two-part ink having the following composition was used as the printing ink.

First liquid Burnock CFB particles 19 parts by weight Toluene / ethyl acetate (1: 1) 54 parts by weight Polyester polyol (Barnock D161) 18 parts by weight Leveling agent 1.0 part by weight Matting agent 2.0 parts by weight Second liquid Burnock DN980 6 parts by weight

Comparative Example 1 Acrylic vinyl chloride resin was used as the resin of the printing ink of Example 1.
An optical card recording medium was prepared in the same manner as in Example 1 except that Sericol 13 (manufactured by Teikoku Ink Manufacturing Co., Ltd.), which was a vinyl acetate mixture, was used.

Comparative Example 2 The resin of the printing ink of Example 2 was an acrylic-vinyl chloride mixture, Sericol ARV (Teikoku Ink Manufacturing Co., Ltd.)
An optical card recording medium was prepared in the same manner as in Example 2 except that the above-mentioned method was used.

When the optical card recording media of Examples 1 to 3 and Comparative Examples 1 and 2 were allowed to stand at 60 ° C. and 90% RH for 500 hours and at 80 ° C. dry for 200 hours, Table 1 shows the results of measuring the reflectance change rate with a spectrophotometer.

[0053]

[Table 1] (Note) The rate of change of reflectance indicates the rate of change when the initial reflectance is 100.

[0054]

As described above, according to the optical card recording medium of the present invention, the influence of the residual solvent contained in the printing layer such as visible information on the recording layer is prevented, and the change in the reflectance of the recording layer is prevented. Can be minimized.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of an optical card recording medium of the present invention.

FIG. 2 is a schematic sectional view showing another example of the optical card recording medium of the present invention.

FIG. 3 is a process chart showing an example of a method for manufacturing an optical card recording medium of the present invention.

FIG. 4 is a schematic sectional view showing an example of a conventional optical card recording medium.

FIG. 5 is a schematic sectional view showing another example of a conventional optical card recording medium.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Recording layer 3 Adhesive layer 4 Protective layer 6 Hard coat layer 7 Magnetic stripe 8 Overcoat layer 13 Preformat 41 Light hiding protective layer 51 Internal printing layer 52 External printing layer 53 Visible information printing 54 Porous light hiding printing Layer 55a Internal porous printing layer 55b External porous printing layer

Claims (7)

[Claims] 1. An optical card recording medium having a recording layer made of an organic dye and having a porous printing layer formed of a printing ink containing a polyester-based porous resin. 2. The optical card recording medium according to claim 1, wherein the porous printing layer is a porous printing layer for concealing visible information and / or light. 3. The optical card recording medium according to claim 1, further comprising a protective layer for protecting the recording layer. 4. The optical card recording medium according to claim 1, wherein the porous printing layer is provided on at least one of both surfaces of the protective layer. 5. The optical card recording medium according to claim 1, wherein the porous printing layer is provided on the recording layer side of the protective layer. 6. The optical card recording medium according to claim 1, wherein the amount of the solvent remaining in the porous printing layer is 100 ppm or less based on the ink. 7. The optical card recording medium according to claim 1, wherein said polyester-based porous resin comprises a polyester-based resin containing fine particles having a particle size of 0.5 to 3 μm.