JPS58209594A - Optical recording medium - Google Patents

Abstract

PURPOSE:To obtain an optical recording medium having a high resolution and a high contrast and capable of a multi-color recording with high speeds by irradiation of near infrared rays without the use of a direct heating means, e.g., thermal recording head, etc., by laminating a near infrared rays absorber and a heat-sensitive chromogenic substance on a base plate. CONSTITUTION:At least one set or more of a near infrared rays absorber 22 (e.g., a dye, such as diethylaminonaphthol squalilium, etc., a metal complex salt, etc.) having absorption waves in near infrared regions of 0.8-2mum, and a heat- sensitive chromogenic material 23 (e.g., a combination of a leuco dye and a developer, a combination of a diazonium salt and a coupler, etc.) are laminated on a base plate 21 (e.g., plastic sheet, glass plate, or other visible rays-transmissive materials) to obtain an optical recording medium. USE:The optical recording medium is suitable for wave-length multiplex optical disc mediums, color microfilms, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an optical recording medium in which recording is performed by irradiation with near-infrared light without using direct heating means such as a thermal recording head. Technical background of the invention and its problems] The thermal recording method is a direct recording method that does not require development or fixing.
It is applied to printers and facsimile machines because of its ease of operation and maintainability. This has caused problems such as adhesion of debris and sticking (adhesion between the recording head and the recording material), impairing recording quality. Furthermore, since the recording head moves while being in close contact with the recording material, a decrease in resolution due to wear of the recording head heating element cannot be avoided.

Furthermore, when performing thermal recording with a recording head, it is usually necessary to heat the recording head to a temperature of 400°C or higher, depending on the type of heat-sensitive material, and the power consumption required for recording is 1 to 5 J/dat.
0This problem becomes more prominent as the recording head becomes denser and larger, and also due to thermal isolation between the heated dots on the recording head that are heated to high temperatures, or due to the recording dots being recorded at high speed. Material? Unless the thermal history during movement is resolved, the time required to record the A-4 version cannot be reduced to less than 1 minute, and
A method has been proposed in which heat-sensitive recording paper is used for recording by causing a light source such as a laser beam to develop an elliptical color. For example, as shown in FIG. 1, an original 13t for recording and transfer is placed under a heat-sensitive recording material consisting of a substrate 1 and a coloring agent 12, and is exposed to light from a light source I6, which is absorbed by the light absorption layer 14 of the original 13. However, in this recording method, the light absorption 1
-The heat generated at
The resolution was disappointing.

Also, the light absorption layer [instead of using the wavelength of the light source? Some attempts have been made to record by incorporating the absorbing dye into the coloring layer.However, fc has not been used for this purpose.
Dye 5 is a visible light-absorbing dye such as Mevlene Blue or Rhodamine B, which has the problem of being colored by itself, resulting in insufficient contrast after recording. , near-infrared absorption color Δkemin P1!
1. Alternatively, recording materials that are coated in microcapsule form are also being considered;
There was a limit to the uniformity of the colored area, and the highest resolution was about 20 lines/a#1. In addition, in a multicolor system in which a plurality of color formers are dispersed, the resolution is further reduced, and the color density is often insufficient due to loss of light intensity in the thickness direction of the color former.

[Purpose of the invention]

In order to solve the above-mentioned drawbacks of the recording medium, the present invention aims to provide a high-contrast, transmitted-light readout type optical recording medium that can perform multicolor recording by multiplexing recording materials by using near-infrared light irradiation. This is what we provide.

[Embodiments of the invention]

Examples of the present invention will be described in detail below.

The optical weight distribution medium of the present invention is a heat-sensitive coloring material and 10, 8-2.
One or more combinations of near-infrared absorbers having an absorption wavelength in the near-infrared region of μm are laminated on a substrate. These thermosensitive coloring materials, near-infrared absorbers, and r
To coat the substrate, a color former and a near-infrared absorber may be mixed, or a heat-sensitive color material layer may be used. A near-infrared light absorber is applied on the substrate 1 and further on this coloring agent layer. May be covered. - As for the substrate, materials that transmit visible light such as plastic ε・-t (Mylar film@), plastic plates (acrylic, polycarbonate), and glass plates? Can be used. .

When used as a reflective light readout type, an opaque material such as high-quality paper can be used as the substrate.As a heat-sensitive material, it is called the NCR type (a combination of co-dye and color developer, a combination of diazonium salt and cup two) A specific leuco dye that is a general C0NCR type material component is crystal violet lactone (
If), benzoylleucomeprene blue (blue), a,
b Bis-dietheramino-no-rotamine r'-4' nitroanilinoctam (dark red), 3.6-bis-dieburaminofluorane-r-f niline ragtam (pink), 3-chloro-6 microhexylaminofluorane (yellow orange) etc.
[Garereru. As a color developer, Bisfe, No/l/A,
4-Hydroxyphenoxide, 4-t-butyl 7L-nor, 4-hydroxyleacetophenone, 4.4'-(sobropylidenediphenol, etc.) are the material components of 0 dif-cytaib' [, diazonium salt and C is P-diazo-N
Examples include ethyl-N hydromycete J-luaniline chloride zinc chloride, P-diazo-N, N-dimethylaniline chloride zinc chloride, 4-benzamide 2,5 diethoxybenzene diazonium chloride zinc chloride, and the like. Cup two [resoruminol, d-)'phthol, 2,7-hydroxynaphthalene 2'-hydroquine naphthalene 3,6-disulfone late sodium, 2,3-
Sodium dihydroxynaphthalene-6-sulfonate,
Acetoaceto-1nilide etc. have a maximum absorption wavelength r in the near-infrared light region of 0, 8 to 2.0 μm.
Compounds with this include mianine dye (Japanese Kanko Color 11 Kyusho @) NK1161 (930ni) - NK104 (79
4ni), NKI748 (859nm).

There are NK427 (803 nm) and the like. The numbers within 0 indicate the absorption peak wavelength r of the dye.
Metal complex salt materials such as tetrabutyl ammonium may also be included. As a specific example, 'C' is the metal complex salt material mentioned above, and 'C' is a near-infrared absorber P A ・10 manufactured by Mitsui Toatsu Fine ■.
01(11(JOom).

PA-1002 (895nm), FA-1003 (88nm)
0r++n).

PA--1005 (850n+n), FA--100
6 (87 (Jr++nJ, etc.) are listed. The number in 0 indicates the absorption peak wavelength of the dye. 0 In addition, dyes such as diethylaminonaphthol squarylium and diethylaminonaphthol squarylium can also be used in their 830 nm absorption range. The near-infrared absorber is in the visible region (4
In the region (00 to 700 nm), the absorption coefficient is only about 1/100 of the maximum absorption wavelength, and the OT ability is to increase only the absorption of near-infrared chain acids while keeping the visible light region nearly transparent. It is.

Next, a method for manufacturing the optical recording medium of the present invention will be explained. As shown in Figure 2, the above coloring material and near-infrared absorber? visible light? A coloring/absorbing agent layer 22 is formed by dissolving it in a transparent binder material and coating it with a spin cord on the substrate 2I.Next, a color developing agent is similarly dissolved in the binder material and applied on the coloring/absorbing agent layer 22. Laminated color former layer 23' (provided. 2
4 is a light source which is a semiconductor laser beam, and 25) is a J coloring section. In this configuration, the coloring sensitivity is high, or the coloring agent partially reacts at the contact interface of the two layers, resulting in so-called "one-color discoloration".
and the near-infrared absorber 1 between the coloring layer 32! 33K is provided with a molten isolation layer.0 This configuration not only prevents background fog, but also prevents the infrared absorber from thermally dissipating from the substrate 3.
35 is a coloring part, and 36 is a light source.This part can have the same sensitivity as the two-layer structure, and 36 is a light source.

In recording using the medium having the above structure, when the semiconductor laser light is irradiated with infrared light corresponding to the absorption wavelength of each near-infrared absorbent, a color corresponding to each absorbent occurs.

The present invention will be explained in detail below. .

(Example 1) Solution (A) with the following composition k 1l141i! L, This r was coated with a spin cord onto an acrylic substrate and then dried at 60°C.

Next, solution (B) (composition is shown below) ii! 14 adjustment,
Spin cord coating was applied over the above coating layer.

The transmitted light intensity of the recording medium obtained in this way? Upon measurement, characteristic 41 shown in FIG. 4 was obtained. 041 is the transmittance of the optical recording medium before irradiation with light.

A slight background fog absorption was observed at 600.400 nmjL8
Absorption of the near-infrared absorber is seen at 50 nm. Pulse light from a semiconductor laser with a wavelength of 850 nm and an output of 10 mW (pulse width 100 nsec) kloImXIOll
When the light was focused and irradiated onto a spot of m, it was colored in a back color as shown by the broken line 43 in Figure WJ4. 43 is the transmittance of the optical recording medium after light irradiation. A metal bang mask? When exposed in close contact with a xenon flash (Xe-ftamh) lamp, similar coloration was observed in 'C', and a line and space of 30 μm could be resolved.

(Example 2) A recording medium was prepared by sequentially coating the solution (C'l, solution (B), and solution (B) with a spin code. 42 in Figure 4 is the transmittance of the optical recording medium before light irradiation. The composition r of the 0 solution (C) and Φ) is shown below.

When this was exposed to a semiconductor laser with a wavelength of 890 nm in the same manner as in Example 1, the coloring characteristics shown in 43 of 1LC4 were obtained. (Example 3) A solution (E) with the following composition was prepared and Similarly to 2, apply mylar to the solution (G)), solution (B), and solution (B).
A recording medium coated with a spin code on a film was exposed to light using a semiconductor laser as in the above example, and a red coloring characteristic shown in wJb diagram IC was obtained. In FIG. 5, 51 is the transmittance of the optical recording medium before light irradiation, and 62 is the transmittance of the optical recording medium after light irradiation. (Example 4) Solution (F) with the following composition % : Prepared and printed 4 times with barcode on acrylic substrate. Furthermore, a solution (C) * was prepared and coated with a spin cord.

The transmitted light intensity of the recording medium obtained in this way and the wavelength 1l100
Characteristics of n semiconductor laser after writing? c M 6
As shown in the figure below. Is the color brown and colored? Indicated.

In Fig. 6, 6I is the transmittance of the optical recording medium for light irradiation;
62 is the transmittance of the optical recording medium after light irradiation.

(Example 5) Solution (E), solution (D), solution (B), and g liquid were sequentially laminated on the recording medium of Example 4 to obtain a recording medium having the structure shown in FIG. 7. In FIG. 7, 71 is a substrate, 72 is a coloring agent/absorbent layer (yellow coloring layer), 73 is a coloring layer (74 is an absorbent layer, 75 is a coloring agent layer, 76 is a coloring agent/absorbent layer), This is an absorbent layer.This recording medium had the r1 transmittance shown in Fig. 8.When exposed to light at a wavelength of 850n+n, this recording medium emits "K color" and "t'g" light with a wavelength of 890nm. Exposure to a red light wavelength of 1100nra produced a yellow color.In this technique, a medium-zero configuration for full color development was performed using a semiconductor laser with each wavelength of Tajiki IQ+nW at a wavelength of 100μtn.
The pulse width of 1 μm for x100 μm (7) thl product exposure was 8 times each. In Fig. 8, No. 8 is the transmittance of the optically poor medium before irradiation with light, 82 is the transmittance of the skin after irradiating the yellow coloring layer with light, and 83 is the transmittance of the red coloring layer when the skin is irradiated with light. , 84 is the transmittance when #color-forming layer r light is irradiated.

〔Effect of the invention〕

As explained above, if the present invention is applied, it will be possible to use a direct heating method such as a thermal head. It is possible to perform recording with high resolution and high contrast without using a semiconductor laser or the like for near-infrared light radiation. In addition, since the coloring agent is uniformly dissolved in the binder and laminated 11, there is no scattering of the irradiated light within each coloring layer, and the multi-can structure in which the coloring agent is laminated in multiple layers can be used. However, it has the advantage of less light loss and higher color sensitivity. At the same time, since the color forming agent is uniformly dissolved and transparency is maintained, the paper also has the advantage that the color contrast and resolution are essentially higher than those produced by the microcapsule dispersion method or the non-uniform dispersion method.

Therefore, the optical recording medium according to the present invention can realize high contrast, high speed, and multicolor recording, and is suitable for application to wavelength multiplexed optical disks and color microfilms.

[Brief explanation of the drawing]

Figure 1 shows the conventional heat-sensitive recording material side;
The figure shows one embodiment of the present invention, a bright diagram, Figure 3 shows another embodiment of the present invention, and Figure 4 shows the second embodiment.
Figure 5 shows an example of color development characteristics in the embodiment shown in Figures 1 and 3, and Figure 5 shows an example of color development properties 1t in the third embodiment of the present invention. A diagram showing an example of the light color characteristics according to the fourth embodiment, FIG. 7 is an explanatory diagram showing the fifth embodiment of the present invention, and FIG. It is a figure showing an example of color development axis property in an example. 21... Substrate, 22... Coloring/absorbing agent layer, 23... Coloring agent layer, 24... Light source (semiconductor laser), 2b... Coloring part, 31... Substrate, 32... Coloring layer , 33...Absorber ML''...Coloring agent layer, 35...Coloring part, 36...
Light source, 7... Substrate, 72... Color former/absorber rWi
(, yellow coloring layer), 73-R color layer ('tlj), 74.
...Absorbent layer, 75...Coloring agent layer, 76...Coloring (A
')・Absorbent layer. Fig. 1 16 10 [Mi No. 20 No. 414 Muff 30 (“-

Claims (1)

[Claims] An optical recording medium characterized in that at least one set of a near-infrared absorber having an absorption wavelength in the near-infrared region of 0.8 to 2 μm and a thermosensitive coloring material are laminated on a substrate.