JPS6027593B2 - Heat mode recording method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat mode recording medium and a recording method.

2. Description of the Related Art Conventionally, various methods have been known for optically performing high-density recording when recording high-frequency signals, such as video signals, on a recording medium.

For example, a recording layer is provided on a support, the recording layer is irradiated with an energy beam (laser beam, electron beam, etc.), the heat generated thereby forms a recess (this is called heat mode recording), and the recording layer is left as it is. There is a way to use it as a record.

This method has a high recording speed and does not require development processing, but the periphery of the recess (recorded bit) formed by the beam may bulge irregularly or be removed by evaporation or melting to form the recess. This was accompanied by a phenomenon in which part of the recorded recording layer scattered and adhered to the surface of the record sheet.
Therefore, regardless of the type of reproduction method, the signal to noise ratio of the obtained signal itself is not good, and when a capacitance type, piezoelectric type, etc. are used as a reproduction method, an extremely large mechanical force acts on the reproduction element, causing the reproduction element to This had the disadvantage of significantly shortening the lifespan of the device. The present invention aims to solve all of the above-mentioned drawbacks and provides a new and superior heat mode recording medium and recording method.

The present invention, which achieves the above object, is a heat mode information recording method in which an energy beam is selectively irradiated onto a recording medium having a heat mode layer and an information recording layer, and heat generated by the energy beam is used to generate heat mode information. This recording method is characterized by comprising a step of selectively removing the layer and the information recording layer, and a step of removing the remaining heat mode layer. Also, as a recording medium suitable for the method,
It is selectively removed by the heat generated by the energy beam,
Further, the present invention provides a recording medium having a heat mode layer whose entire layer is removable and an information recording shoulder, and furthermore, a recording method for creating a large number of subsequent discs using the recording disc obtained by the above method as a master. It gives The recording medium and recording method of the present invention will be explained in detail below.

In the present invention, the basic structure of the recording medium consists of a heat mode layer, an information recording layer, and a substrate. However, the heat mode layer is a layer that is removed by thermal action such as evaporation or melting by a beam, and the information recording layer is a layer that is removed by the thermal action of a beam at the same time as the heat mode layer. (a portion) is selectively removed and represents a layer on which final information recording is performed without being changed upon removal of the residual heat mode layer. As the substrate, glass,
Examples include ceramics, organic polymers, metals, etc., and sheet, film, or hard plate shapes are selected depending on the purpose.

Typical materials for the heat mode layer and the information recording layer include chalcogen or chalcogenide, metals, metal oxides, and organic polymers. The chalcogen or chalcogenide used in the present invention is not limited to stoichiometric proportions, but is composed of sulfur group elements (S, Se, T, etc.) in any proportion.
e) as a main component.

Typical examples that are effective in the present invention include simple substances such as S, Se, and Te, or 戊-S system, 戊-Se system, 戊-Te system,
-S system, As-Se system, As-Te system, S-Se system, S
e-Te system, Te-S system, Sb-S system, Sb-Se system,
Sb-Te series, Bi-S series, Bi-Se series, Bi-Te
29 series such as system, or As-S-Te system, As-Se-
It is a ternary system such as Te system or Sb-As-S system. To name a few specific ones, snake S, snake 2S3, WS2,
False 2S3, SQS3, Bi2S3, Bi2Se3, Bi
Je3 etc. Furthermore, various mixed systems of the chalcogen or chalcogenide substances, or thallium, halogen, Cu, Ag, Cd, Pb, etc., or alkali metals such as Na, K, alkali metals such as Ca, Sr, etc. Si
, Q, etc., lanthanum-based rare earths such as Sm, actinide-based rare earths such as U, etc., may be added alone or in various combinations to chalcogen or chalcogenide.

Note that many of these substances are easily soluble in alkaline solutions, but exhibit strong resistance to acids. Metals used in the present invention include Cr, Ni, Fe, Co, Cu, Ag
, Au, Zn, A Yu, Cd, M○, Rh, Pd, Pt,
These include metals such as lr, Bi, Sn, Pb, and ln, and alloys containing these metals.

Further, semiconductors such as Q and Sj are also used. Examples of organic polymer substances include polymethyl methacrylate, polyisobutyl methacrylate, polyethylene, polypropylene, polystyrene, polyvinyl chloride, styrene acrylonitrile copolymer, vinyl chloride-vinylidene chloride copolymer, polyvinyl butyral, cellulose acetate, and polycarbonate. Common organic polymers such as

Specific examples of metal oxides include CrQ, ln203, Ni○, MOO3, Mg0, Mh
02, SnQ, Ti02, W03, V205, ZN0,
It is the 2nd class of Z. In addition, in the recording method of the present invention, the most common method for removing the entire remaining heat mode layer is to use an acid, oxidizing solution, alkaline solution, ordinary organic solvent, or the like.

Alternatively, various wet methods such as atomizing the liquid as described above may also be used. Still another method may be to evaporate or melt away the remaining heat mode layer without causing any change in the recorded area. The liquid for removing the residual heat mode layer is appropriately selected depending on the properties of the materials used for the heat mode layer and the information recording layer.

To give some specific examples, typical acids or oxidizing solutions include nitric acid, sulfuric acid, (including dilute sulfuric acid, hot concentrated sulfuric acid, etc.), chromic acid mixture (K2Cr207-ratio S04), Aqua regia, ammonium nitrate solution, ferric nitrate solution, etc., as alkaline solutions, aqueous or alcoholic solutions of hydroxides of alkali metals such as Li, Nb and K, or alkali metals such as Ba and Ca, or aqueous solutions of alkaline compounds. etc., and ordinary organic solvents include:
These include aliphatic and aromatic hydrocarbons, chlorinated hydrocarbons, alcohols, ketones, etc. The configuration or recording method of the present invention will be described below with reference to the drawings.

FIG. 1 shows the basic configuration of the present invention.

That is, an information recording layer 2 is formed on a suitable substrate 1. Various methods are used depending on the material, such as evaporation, sputtering, or especially in the case of organic polymer layers, coating, ultraviolet rays, and electron beam polymerization. Further, a heat mode layer 3 is formed thereon by a similar method to obtain a recording medium.
Figures 2a, b and c show an example in which a chalcogen or chalcogenide layer selected from the above-mentioned series of materials is used as the heat mode layer and a metal layer is used as the information recording layer.

However, in these figures, numbers 1, 2, and 3 refer to the first
Similarly to the figure, a substrate, an information recording layer, and a heat mode layer are shown, respectively. As shown in FIG. 2a, an energy beam 6 corresponding to the information is selectively irradiated, and the upper chalcogen or chalcogenide layer 3 and the information recording layer 2 are heated by the energy beam 6.
and remove. At this time, scattered particles 4 of chalcogen or chalcogenide or raised portions 5 around the removed portions are generated on the heat mode layer, and if this continues, a good recording disc cannot be obtained. Next, as shown in FIG. 2b, the remaining chalcogen or chalcogenide layer 3, scattered particles 4, raised portions 5, etc. are all dissolved and removed using an alkaline solution, thereby making it possible to record a good surface condition that cannot be obtained by conventional methods. Note that in the above example, a method was shown in which the entire thickness of the information recording layer was removed using heat mode, but the second
Another embodiment of the present invention is a method in which only a portion of the thickness of the information recording layer is removed in the heat mode, and then all the remaining heat mode layer is removed, as shown in FIG. Note that whether to remove all or part of the thickness of the information recording layer depends on various physical properties of the material (reflectance, thermal conductivity, specific heat, etc.) and the magnitude or concentration of the beam energy. It is very difficult to unambiguously determine the thickness of the heat mode layer or the information recording layer.

However, as a result of studies conducted by the present inventors, the heat mode layer is easily removed by the energy beam, thermal changes such as melting and evaporation do not occur in areas other than those corresponding to the energy beam, or the substrate is Considering that it will not be significantly changed by the beam, the range is approximately 0.03 to 0.5, particularly preferably 0.05 to 0.5.
It is preferable to set the range to 0.3 mm. On the other hand, the thickness of the information recording layer does not require strict conditions compared to the heat mode layer, but consideration should be given to the mechanical strength of the recesses (recording bits) and the need to increase the S/N ratio during reproduction. Then 0.1～
It is in the range of 1 mm, particularly preferably in the range of 0.2 to 0.4 mm. As a variation of this, a chalcogen or chalcogenide layer may be formed as a heat mode layer on a sufficiently polished metal slope that serves both as an information recording layer and a substrate.
An example of this is shown in FIG. In FIG. 3a, a chalcogen or chalcogenide layer 9 is formed as a heat mode layer on a metal plate 8 serving as an information recording layer and a substrate, and this recording medium is selectively irradiated with a beam 6 to generate heat by the beam. The heat mode layer 9 and the information recording layer 8 are selectively removed using heat. In this way, recesses 12 (recorded bits) are formed.
At this time, due to the irradiation of the beam 6, scattered objects 10 or peripheral raised portions 11 are generated as in FIG. 2a. Next, as shown in FIG. 3b, if the remaining chalcogen or chalcogenide layer 9 is dissolved and removed with an alkaline solution, an excellent recording disk with good surface condition and high resolution can be obtained. In addition, it is also a preferable example to use a hard organic polymer plate (for example, an acrylic plate) instead of the metal plate in the above example. There are numerous configurations of the recording medium used in the recording method of the present invention. Some of the typical examples are shown in Table 1. Table I The above table also lists variations in which the information recording layer serves as both the substrate, ie, examples in which a metal plate or an organic polymer hard plate is used as the information recording layer.

In addition, considering the ease with which the heat mode layer is removed by beam irradiation, the fact that the substrate does not change significantly, the mechanical strength of the information recording layer, etc., A, A, and A are preferred among those listed in vote-1 above. B, 0, E, G, day, J
, K and L types, particularly preferably A,
They are of type B, D and day. In any type of recording medium, the conditions required for the materials of the heat mode layer and the information recording layer are {1' layer formation is easy; In particular, the materials of these two layers have different chemical properties (for example, solubility in acids, alkalis, or organic solvents). Therefore, as long as the condition {3} is satisfied, the heat mode layer and the information recording layer may be made of a combination of materials of the same type. The recording method and recording medium of the present invention can be suitably used for various information recording media.

For example, it is widely applied to micro images, super micro images, COM, micro facsimile, video signal recording, etc. Among these, application to sheets or disks for recording video signals is very preferable. That is, when the present invention is used in a recording medium for video signals, real-time, high-resolution recording is possible, and the structure is independent and processing is simple. In addition, the surface of the recording disk on which information is recorded is extremely smooth, and the shape of the recorded bits is also good, so the S of the reproduced signal is
It has the advantage that the N ratio is improved, and the life of the recording disk or the reproducing element is inevitably extended because the reproducing element is not damaged. Furthermore, the recording medium of the present invention is extremely preferable for the reasons mentioned above when used as a master for obtaining a large number of subsequent discs after recording.

Various embodiments are preferably used as the recording medium in the recording method of the present invention.

For example, if the substrate is composed of an organic polymer layer that is susceptible to thermal deformation, a reflective layer (generally made of a metal with a high reflectance layer), or an anti-reflection layer provided on the heat mode layer to increase energy efficiency. The present invention will be explained in more detail with reference to Examples below.

Example 1 a) A glass plate having a thickness of about 1 inch and a diameter of about 3:1 was vacuum-coated with A to a thickness of about 0.2 mm.

The deposition conditions were a tungsten board, a vacuum degree of 8×10 orr, and a deposition source temperature of about 1000°C.

Next, WS was vacuum-deposited on this A layer to a thickness of about 0.05 μm. Vapor deposition conditions are tungsten board, vacuum degree 1×
10-5 ■n, and the evaporation source temperature was about 70,000. A recording medium was obtained in the manner described above. In addition, the equipment used for recording is
The basic configuration was shown in FIG.

That is, an argon ion laser 13 with an output of about 2 W, an optical modulator 15 driven by a video signal 14, and a reflecting mirror 16.
, an optical system consisting of ten on-head microscopic objective lenses 17 for condensing light, a turntable 19 that rotates in a plane perpendicular to the optical axis of the light beam 18 emitted from this optical system, and a motor for driving the turntable. 20, it further comprises a drive system including a mechanism for integrally moving the reflecting mirror 16 and the condensing lens 17 in the horizontal direction in response to the rotation of the turntable. For this device, the surface of the recording medium 21 is a condensed beam (the spot size is approximately 1r in the scanning direction, and has a rectangular shape with a length of approximately 3 mm in the direction perpendicular to the scanning direction). mounted to match the focal point of the The turntable was rotated at 180 rotations per minute, and the heat mode layer (QS
The information recording layer (layer A) and the information recording layer (layer A) were removed by heat mode to allow the bit to hang down on the glass surface. Then, the remaining heat mode layer (QS) was dissolved and removed for 6 seconds with a saturated NaOH/ethanol solution. When the recording medium recorded in the above manner was observed using a scanning electron microscope at 500 stitches, no scattered particles or bulges were observed on the surface of the recording disk, and no concave portions (recorded bits) were observed. The shape was also very good.

The resolution was over 2000 lines/pig. When recording was performed with the laser output reduced to IW and other conditions being the same, the recesses (recorded bits) were approximately 0.1 mm deep and did not extend all the way to the glass surface, resulting in recording as shown in Figure 2c. was carried out. This recording disk also had a sufficiently smooth surface and an extremely good shape of the recesses. Furthermore, recording was performed by changing the heat mode layer and information recording layer as shown in the table below, and then the remaining heat mode layer was dissolved and removed.

Table 2 below summarizes the heat mode layer, information recording layer, layer formation method, heat mode layer removal method, etc. However, in the following description, "temperature" in the bottle for the heat mode layer and information recording layer formation method indicates the vapor deposition source temperature, and the time in the bottle for the heat mode layer removal method indicates the time required for dissolution and removal. shall be taken as a thing. Table 2 Example 2 Recording was carried out in the same manner as in Example 1 except that the combination of heat mode layer and information recording layer was changed as follows, and almost the same results were obtained.

Example 3 A WS layer (thickness: about 0.2A) was formed by summer air vapor deposition under the same conditions as in Example 1 on a well-polished A disk with a diameter of about 30 mm and recorded. It was used as a medium.

Next, recording was performed on the heat mode layer using the recording device used in Example 1, and then QS was performed using a dilute Na2C03 solution.
was dissolved and removed for a short time to obtain a record disc. The surface of the recording disk and the recorded bits were in fairly good condition, and had a practically sufficient resolution (2000 or more lines/accumulation). Example 4 W was placed on an acrylic resin disk with a thickness of about 1 to 3 mm and a diameter of about 30 mm.
S was vacuum-deposited to a thickness of about 0.07 mm to form a recording medium.

The vapor deposition conditions were almost the same as in Example 1. Recording was carried out in the same manner as in Example 1 with a laser output of about 3 W, and the remaining WS layer was removed by dissolving it with a saturated NaOH/ethanol solution for about 7 seconds. The obtained recording disc had a recess (recording bit) with a depth of about 0.1 A formed in the acrylic plate. The surface of the record is smooth and the resolution is sufficient for practical use (approximately 1
500 lines/skin). Note that recording was performed in the same manner using Biyo3 and WS2 as the information recording layer, and similar results were obtained.

Example 5 On the same substrate as in Example 1, a core 2Se3 layer was vacuum deposited to a thickness of about 0.3 mounds.

Further, Cr was vacuum-deposited thereon to a thickness of about 0.1 mound.
The deposition conditions for forming these layers were almost the same as in Example 1. Recording was performed on the heat mode layer and the information recording layer of this recording medium using the apparatus used in Example 1.

Note that the output of the laser beam was approximately 2W. Thereafter, the remaining Cr layer was dissolved and removed using dilute Hb04 grade.

The condition of the surface and recording tracks of the thus obtained recording disk was very good as in Examples 1, 2 and 3, and the resolution was 2000 or more lines/rib. Furthermore, recording was carried out by changing the heat mode layer, information recording layer, heat mode layer removing liquid, etc. as shown in Table 3 below, but almost the same results were obtained.

Table 3 Example 6 On the substrate of Example 1, in the same manner as in Example 1, a QS layer was formed with a thickness of about 0.5 mounds, and an ln203 layer was formed on it with a thickness of about 0.1 mm. It was used as a recording medium.

Recording was performed using the same device as in Example 1. Then, the remaining ln203 layer was removed using diluted HC, and a good recording disc was obtained. Also, when recording was carried out by changing the heat mode layer and the information recording layer as shown in Table 4 below, very good results were obtained.

Table 4 Example 7 W03 was deposited on the same substrate as in Example 1 to a thickness of about 0.5 mm by electron beam evaporation (degree of vacuum: 1 x 10-5 tons).

Next, in the same manner as in the example in Table 2 of Example 1, the thickness was approximately 0.
A recording medium was prepared by vacuum-depositing 1 ml of polyethylene. Using the apparatus of Example 1 on this recording medium, the laser output was approximately 2W.
Recording was then carried out, and the remaining polyethylene layer was dissolved and removed in a warm benzene bath. A recessed portion having a depth of about 0.4 mm was formed in the obtained record disc. There were no protrusions around the concave portion, and good recording was performed. Further, recording was carried out by changing the heat mode layer, information recording layer, heat mode removing liquid, etc. as shown in Table 5 below, and good results were obtained as in the above example.

Table 5 Example 8 Signals were reproduced using a recording disk obtained by recording on the WS-ln recording medium of Example 1.

The reproduction method was an optical method. That is, a semiconductor laser beam for reading was irradiated from the surface of the recording disk, and the optical signal received by a reproducing element consisting of a Si photodetector was demodulated by a demodulator and converted into an image signal. The images obtained were clear. Note that WS-Sn in Example 1
, Fu2S3-Moo3, Bi-QS in Example 5,
Bi-W03, polyethylene-Cr0 in Example 7
Recording and reproduction were performed in the same manner on a recording medium such as No. 2, and a good reproduced image was obtained. Example 9 A styrene layer having a thickness of about 500 Å was formed on the recording disk obtained in Example 3 in the same manner as in Example 7, and signal reproduction was performed using the capacitive reproduction method.

That is, a stylus electrode was used as a reproducing head, the capacitance between the electrode and the conductive layer (A-substrate) was detected, and this signal was demodulated by a demodulator to obtain an image. The reproduced image was extremely clear.

Example 10 The recording disc obtained by recording on the QS-ln recording medium of Example 1 was plated with Ni, and the plated layer was peeled off to serve as a master for producing a large number of double-engraved discs.

Next, the master vinyl chloride plate was heat-pressed and then cooled to obtain a transparent vinyl chloride disk.

Vacuum evaporation of 300A thick A layer on the surface (vacuum level 5~
A disk was completed by applying a polymethyl methacrylate layer to a thickness of about 1 mm to serve as a protective layer.

The surface of the disc was extremely smooth. When signal reproduction was performed in the same manner as in Example 9, a good image was obtained.

Moreover, WS-1 ratio 03 of Example 1, Bi2S3- of Example 2
Recording and reproduction were similarly carried out on recording media of the Mn02, Cr-As 3 and Bi-S types of Example 5, and good results were obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the basic structure of the recording medium of the present invention;
FIGS. 2 and 3 are cross-sectional views showing one embodiment of the recording method of the present invention, and FIG. 4 is an explanatory view showing an apparatus used for recording. In the drawings, 1 is a substrate, 2 is an information recording layer, 3 is a heat mode layer, 4 is a scattering of the heat mode layer, 5 is a raised part around the removed part, 6 is a laser beam, 7 is an information recording bit, 8 is an information recording layer that also serves as a substrate, 9 is a heat mode layer, 10 is a scattering caused by the heat mode, 11 is a raised area around the removed portion, 12 is a recording bit, 13
is an argon ion laser, 14 is a video signal, 15 is an optical modulator, 16 is a reflecting mirror, 17 is a condenser lens, 18 is a beam, 19 is a turntable, 20 is a drive motor,
Reference numeral 21 indicates a recording medium. Younger brother 1 illustration, Chrysanthemum 2 illustration, younger brother 4 illustration

Claims (1)

[Claims] 1. A step of selectively irradiating an energy beam onto a recording medium having a heat mode layer and a recording layer, and selectively removing the heat mode layer and the recording layer with the heat generated by the energy beam, and removing the remaining heat mode layer. A heat mode recording method comprising the step of: