JP4049549B2 - Optical information medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to an optical information medium on which optically reproducible information is recorded or can be recorded, and in particular, a water-based ink pen or ink jet is formed on a surface opposite to a translucent substrate on which recording and reproduction light is incident after manufacturing. The present invention relates to an optical information medium that can be displayed with water-based ink using a printer.
[0002]
[Prior art]
Currently, in the field of audio and the like, an optical information medium (hereinafter referred to as “CD”) having the name of a compact disc is widely used. In addition, with the spread of personal computers, CD-ROMs are often used as optical media for storing the data. Furthermore, with the recent development and practical application of short wavelength lasers, DVDs (Digital Versatile Discs) that enable higher density recording / reproduction are becoming more popular. This DVD includes a DVD-ROM for computer data in addition to a digital video disk for video. In the future, a music-only DVD will also be released.
[0003]
In CD and CD-ROM, a reflective layer is formed by depositing gold or aluminum on a translucent substrate made of a donut-shaped disc such as polycarbonate, and a protective layer such as an ultraviolet curable resin is provided thereon. It has a covered structure. The data is recorded by forming concave and convex pit rows on the surface of the translucent substrate according to a spiral arrangement. The pit row is formed in advance by following a mold such as a stamper when the light-transmitting substrate is formed, and the reflection layer is provided thereon.
[0004]
The basic structure of a DVD or DVD-ROM is the same as that of a CD or CD-ROM, but the thickness of the translucent substrate is half that of the CD, and by bonding the two translucent substrates, The same thickness as the CD is secured as a whole disc thickness. For example, in the most common single-sided DVD or DVD-ROM, an uneven pit row is formed, and there is no such pit row or reflection layer on a translucent substrate on which a reflection layer is provided. Another substrate is attached.
[0005]
Furthermore, in addition to CDs and DVDs in which data is recorded in advance by the pit rows as described above, CD-R, CD-RW, and DVD that can record data by optical means after the manufacture of optical information media. An optical information medium such as -R or DVD-RW has also been developed and used.
[0006]
In such an optical information medium, an ink receiving layer that absorbs water-based ink is provided on the surface opposite to the translucent substrate on which recording light and reproduction light are incident, and water-based ink is used with a water-based ink pen or an inkjet printer. Optical information media that can be displayed have also been developed. A conventional optical information medium of this type is provided with an ink receiving layer composed of a single layer on which a water-based ink can be fixed on a protective layer or a bonded substrate.
[0007]
[Problems to be solved by the invention]
Today, color printing by an ink jet printer is frequently performed. Color printing by an inkjet printer uses a plurality of color ink nozzles, and prints by adjusting the color according to the combination of ink colors sprayed on each pixel of the ink receiving layer and the amount of ink. In this case, in order to obtain a natural and good color development, a plurality of colors of ink sprayed on individual pixels are quickly absorbed without crossing each other and fixed on the ink receiving layer of the optical information medium. is necessary. Furthermore, in order to eliminate fading or the like of the printed display, it is necessary to fix the ink adhering to the ink receiving layer while it is absorbed and held inside.
[0008]
The ink receiving layer formed on the optical information medium for the purpose as described above is designed to promptly absorb and fix the attached water-based ink. However, if the hydrophilicity of the ink receiving layer is increased in order to promptly absorb and fix the water-based ink, moisture on the hand and moisture in the air are easily absorbed, resulting in stickiness. This makes it difficult to handle the optical information medium. Further, the ink retention is deteriorated due to the absorption of moisture, and the durability of the printed display is deteriorated. For this reason, it has been difficult to satisfy both conflicting demands for ink absorbability of the ink receiving layer and prevention of stickiness.
[0009]
In view of the problems in the optical information medium having the conventional ink receiving layer, the present invention can satisfy the conflicting demands of quick absorption of ink, fixing property, and suppression of stickiness on the surface. It is an object of the present invention to provide an optical information medium having good properties, high retention of printed display, and less stickiness.
[0010]
[Means for Solving the Problems]
In the present invention, in order to achieve the above object, the ink receiving layer 7 formed on the surface opposite to the translucent substrate on which the recording light and reproduction light of the optical information medium are incident is formed as a single layer film. It is formed by a plurality of layers. More specifically, the ink fixing layer 8 is formed on the lower layer side, and the ink transmission layer 9 is formed thereon. Here, the ink fixing layer 8 is a layer that absorbs and fixes a water-based ink, and the ink transmission layer 9 is a layer that has little fixing property of the water-based ink but easily transmits the water-based ink.
[0011]
That is, the optical information medium according to the present invention has a translucent substrate 1 that transmits reproduction light, and an optically readable signal is recorded by the reproduction light incident from the translucent substrate 1 or An ink receiving layer formed with a recording layer (4) made of an organic dye capable of recording and capable of receiving and holding water-based ink on the surface opposite to the translucent substrate 1 The ink receiving layer 7 is composed of an ink fixing layer 8 capable of fixing water-based ink and a porous film having fine through holes formed on the ink fixing layer 8 and applied to the surface. aqueous ink permeable to the possess an ink permeable layer 9 to be transmitted to the ink-fixing layer 8, the weight ratio 1 to the ink-permeable layer (9) of the filler particle size 0.1~50μm the binder Apply a 30-fold uniformly dispersed paint, Are those formed by燥.
[0012]
The ink fixing layer 8 is a layer that absorbs and fixes water-based ink, and is composed of a hydrophilic film mainly composed of a hydrophilic resin. The ink permeable layer 9 is a layer that transmits water-based ink, and is formed of a porous film made of fine particle filler and binder.
[0013]
In such an optical information medium, the water-based ink applied to the surface of the ink receiving layer 7 is quickly taken into the ink receiving layer 7 by the upper ink permeable layer 9 and reaches the ink fixing layer 8 when the ink receiving layer 7 is reached. To settle. For this reason, since the ink applied to the ink receiving layer 7 does not stay on the surface of the ink receiving layer 7, different color inks are not mixed on the surface of the ink receiving layer 7. Thereby, good color development is obtained.
[0014]
Further, since the water-based ink applied to the surface of the ink receiving layer 7 does not remain on the surface of the ink receiving layer 7, even if the surface of the ink receiving layer 7 is rubbed with a finger, the water-based ink will not be faded. Furthermore, even if the ink permeable layer 9 transmits moisture in the atmosphere, the water-based ink does not exist on the surface of the ink receiving layer 7, so that the ink does not bleed along the surface. In addition, the ink permeable layer 9 on the surface side of the ink receiving layer 7 does not need to have high hydrophilicity because it simply transmits water-based ink quickly and does not require fixing properties. Therefore, the surface of the ink receiving layer 7 is not sticky to a finger or the like, and the optical information medium can be easily handled.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described specifically and in detail with reference to the drawings.
As an example of the optical information medium according to the present invention, examples of a write-once optical information medium are shown in FIGS.
The translucent substrate 1 is a transparent disk-shaped substrate having a center hole 9 in the center. The translucent substrate 1 is generally made by injection molding a transparent resin such as polycarbonate or polymethyl methacrylate (PMMA).
[0016]
A clamping area is set outside the center hole 2 on one side of the translucent substrate 1 having translucency, and the outer peripheral side of the clamping area is a data recording area. A tracking guide 3 made of a spiral groove is formed in the data recording area of the translucent substrate 1. The pitch of the tracking guide 3 is 1.6 μm for a CD and 0.74 μm for a DVD, for example.
[0017]
After preparing such a translucent substrate 1, the recording layer 4 is formed on the main surface of the translucent substrate 1 as shown in FIGS. 1 to 3. For example, the recording layer 4 is formed by applying an organic dye such as a cyanine dye or a methine dye by means such as spin coating.
Further, a reflective layer 5 made of a metal film such as gold, aluminum, silver, copper, or palladium, an alloy film thereof, or an alloy film obtained by adding a trace component to these metals is formed on the recording layer 12. Further, a protective film 6 such as an ultraviolet curable resin is formed from the inner periphery to the entire outer periphery of the translucent substrate 1 so as to cover the reflective layer 5.
[0018]
An ink receiving layer 7 is formed on the protective film 6. The ink receiving layer 7 includes a lower ink fixing layer 8 and a surface ink permeable layer 9. The former ink fixing layer 8 is a layer that absorbs and fixes water-based ink, and is a layer made of a hydrophilic resin. On the other hand, the latter ink permeable layer 9 is a layer that quickly transmits the aqueous ink applied to the surface of the ink receiving layer 7 to the lower layer and sends it to the ink fixing layer 8, and is a porous medium having fine through holes. It consists of sex film.
[0019]
First, a heat-drying hydrophilic resin such as polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), or a cellulose derivative is applied to the surface of the protective film 6, and this is heated and dried to form the ink fixing layer 8. To do. Alternatively, a radiation-curable hydrophilic resin such as dimethylacrylamide (DMAA), 2-hydroxyethyl acrylate, or an acrylamide derivative is applied to the surface of the protective film 6 and cured by irradiating with radiation such as ultraviolet rays. The fixing layer 8 is formed. To the hydrophilic resin, inorganic particles such as silica, alumina, calcium carbonate, etc., having a particle size of about 0.1 to 50 μm are added in a slight amount, specifically 5 to 10% by weight based on the hydrophilic resin. May be. The thickness of the ink fixing layer 9 is suitably about 5 to 20 μm.
[0020]
Next, a coating material in which fine filler is dispersed in a resin binder is applied on the ink fixing layer 8 and dried to form an ink transmission layer 9 having fine through holes. As the filler dispersed in the paint, inorganic particles such as silica, alumina, calcium carbonate and the like having a particle size of about 0.1 to 50 μm are used. As the binder, a resin such as polyvinyl butyral or polyethylene glycol is used, and a paint in which a filler having a weight ratio of 1 to 30 times is uniformly dispersed with respect to the binder is used.
[0021]
The ink permeable layer 9 formed in this way has an infinite number of fine gaps, that is, fine pores between the filler component and the binder component dispersed in a relatively large amount due to shrinkage of the binder during drying. . The fine through holes permeate and permeate the water-based ink applied to the surface by capillary action, and send it to the ink fixing layer 8 below.
[0022]
In the embodiment shown in FIGS. 1 to 3, the translucent substrate 1 is covered so as to cover the reflective layer 5 formed on the translucent substrate 1 via the recording layer 4 as in the case of CD-R. An ink receiving layer 7 was formed on the protective layer 6 formed from the inner periphery to the entire outer periphery. On the other hand, in the embodiment of FIG. 4, another substrate 11 is attached to the surface side of the translucent substrate 1 on which the recording layer 4 and the reflective layer 5 are formed via the adhesive layer 10 as in the DVD-R. The combined optical information medium is shown. In this case, the ink receiving layer 7 is provided on the surface side of the substrate 11 where no recording light or reproduction light is incident. The ink receiving layer 7 also has a multi-layer structure of an ink fixing layer 8 and an ink transmission layer 9 as in the above-described embodiment.
Each of the ink fixing layer 8 and the ink permeable layer 9 is not a single layer but may be formed of a plurality of layers.
[0023]
【Example】
Next, specific examples of the present invention will be described.
Example 1
A grooved tracking guide having a half width of 0.8 μm, a depth of 0.08 μm, and a track pitch of 1.6 μm is formed in a diameter range of 46 to 117 mmφ. The outer diameter is 120 mmφ, the inner diameter is 15 mmφ, and the thickness is 1.2 mm. An optical substrate was prepared.
[0024]
A surface of the translucent substrate 1 on which the tracking guide 3 was formed was spin-coated with a cyanine dye dissolved in a solvent and dried to form a recording layer composed of a dye film having an average film thickness of 130 nm. On this, gold was sputtered to form a reflective layer having a thickness of 100 nm. Next, an ultraviolet curable resin was applied by spin coating, and this was irradiated with ultraviolet rays and cured to form a protective layer having a thickness of 10 μm.
[0025]
Next, a coating material is prepared by dispersing 10% by weight of a silica fine particle having an average particle diameter of 7 μm in a 20% by weight aqueous solution of polyvinylpyrrolidone (PVP), and this is printed on the protective layer by a screen printing method. did. Subsequently, the coating film was dried at a temperature of 60 ° C. to form an ink fixing layer having a film thickness of 15 μm.
[0026]
Next, a paint in which 30% by weight of a filler composed of silica fine particles having an average particle diameter of 5 μm is dispersed in a 1% by weight methyl ethyl ketone solution of polyvinyl butyral is printed on the ink fixing layer by a screen printing method. did. Subsequently, the coating film was dried by applying a temperature of 60 ° C. to form an ink permeable layer having a thickness of 10 μm. As a result, an ink receiving layer was formed on the surface of the protective layer.
[0027]
An image was printed with water-based color ink on the surface of the ink receiving layer of the optical information medium thus obtained using a bubble jet printer. As a result, a clear image with vivid color was obtained. After printing, the surface of the ink receiving layer was rubbed hard by hand, but the printed image did not fade. Further, the PET film was pressed against the surface of the ink receiving layer in an environment of 23 ° C. and 85%, but the film did not stick. .
[0028]
(Example 2)
In Example 1, a coating material was prepared by dispersing 10% by weight of silica fine particles having an average particle diameter of 10 μm in a solution of 10% by weight of carboxymethylcellulose dissolved in dimethylacrylamide. Printed on the protective layer. Subsequently, the coating film was irradiated with ultraviolet rays and cured to form an ink fixing layer having a film thickness of 15 μm. Next, a coating material in which 30% by weight of a silica fine particle having an average particle diameter of 5 μm is dispersed in a 5% by weight methyl ethyl ketone solution of polyethylene glycol is prepared, and this is printed on the ink fixing layer by a screen printing method. did. Subsequently, the coating film was dried at a temperature of 60 ° C. to form an ink permeable layer having a thickness of 10 μm.
Except for the above steps, an optical information medium having an ink receiving layer on the surface of the protective layer was prepared in the same manner as in Example 1.
[0029]
Also for this optical information medium, an image was printed with water-based color ink using a bubble jet printer on the surface of the ink receiving layer in the same manner as in Example 1. As a result, a clear image with vivid color was obtained. After printing, the surface of the ink receiving layer was rubbed hard by hand, but the printed image did not fade. Further, the PET film was pressed against the surface of the ink receiving layer in an environment of 23 ° C. and 85%, but the film did not stick.
(Comparative example)
In Example 1, an optical information medium was manufactured in which the ink receiving layer was formed only by the ink fixing layer without forming the ink transmission layer.
Also for this optical information medium, an image was printed with water-based color ink using a bubble jet printer on the surface of the ink receiving layer in the same manner as in Example 1. As a result, a clear image with vivid color was obtained. However, when the PET film was pressed against the surface of the ink receiving layer in an environment of 23 ° C. and 85%, film sticking occurred on the surface of the ink receiving layer.
[0030]
【The invention's effect】
As described above, the optical information medium according to the present invention can satisfy both conflicting demands for quick ink absorption, fixing property and suppression of surface stickiness. Thus, an optical information medium having good properties and the like, high retention of the printed display, and less stickiness can be obtained.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a half section of a state before bonding two substrates showing an optical information medium according to an embodiment of the present invention.
FIG. 2 is a partial longitudinal sectional perspective view showing the optical information medium.
FIG. 3 is a longitudinal sectional side view showing a main part of a part of the optical information medium.
FIG. 4 is a longitudinal sectional side view of an essential part showing a part of an optical information medium according to another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Translucent board | substrate 7 Ink receiving layer 8 Ink fixing layer 9 Ink transmitting layer

Claims (3)

An organic dye having a translucent substrate (1) that transmits the reproduction light, and an optically readable signal recorded by the reproduction light incident from the translucent substrate (1) In the optical information medium having the recording layer (4) formed of the ink receiving layer (7) capable of receiving and holding the water-based ink on the surface opposite to the translucent substrate (1). The ink receiving layer (7) is composed of an ink fixing layer (8) capable of fixing water-based ink, and a porous film having fine through holes formed on the ink fixing layer (8). the ink permeable layer is transmitted through the aqueous ink applied to the surface and sends the ink-fixing layer to (8) (9) possess a, the ink permeable layer (9) of binder filler particle size 0.1~50μm Apply paint uniformly distributed 1 to 30 times weight ratio , An optical information medium characterized by being formed by drying.   The optical information medium according to claim 1, wherein the ink fixing layer is a hydrophilic film containing a hydrophilic resin as a main component.   The optical information medium according to claim 1 or 2, wherein the ink permeable layer (9) is a porous film made of a particulate filler and a binder.

Images