JPS5862844A - Production of disc - Google Patents

Abstract

PURPOSE:To obtain a disc of high S/N which permits monitoring by dissolving prescribed nitrocellulose and a dye sensitizing agent at prescribed weight fractions in org. solvents, spin-coating the solns. on a substrate and irradiating modulated laser beams thereto. CONSTITUTION:A material contg. >=97% alpha cellulose having prescribed number- average degree of polymn. is nitrated to prescribed rates of nitration, whereby nitrocellulose is obtained. The nitrocellulose and a dye sensitizing agent are dissolved respectively in org. solns. and the solns. are filtered and are then mixed so as to attain prescribed weight fractions. The resultant org. solvent is spin-coated as an information recording layer 3 on a substrate, and the laser beams modulated by, for example, an audio signal, are irradiated onto the layer 3. Then the irradiated parts sublimate by the effect of heat and form pits 4. Thus the disc of high S/N which permits monitoring is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing information recording plates, special video disks, and PCM audio disks.

Traditionally, κ photoresists have been used to manufacture information storage plates. In other words, prepare a master disk (such as glass with a polished surface), wash and cool the master disk (approximately 1 hour), coat this master disk with a thin layer of κ photoresist, pre-bake, and cool it after death. Approximately 1 hour of work 1!!).

This photoresist is coated and a signal is recorded by irradiating it with a laser beam modulated from a signal κ (about 1 to 2 hours!).

This exposed master is developed, washed with water, drained, and then afterbaked and cooled (approximately 1 hour of work).
. [This is k] Table ii A master disk on which bits corresponding to the NK recording signal are formed is obtained. Further bits are formed, and a reflective film of κ metal is coated on the recording surface (about 45 minutes O process). The coated master disc is played back using an inspection playback machine and inspected for dropouts, etc. (approximately 1 to 2 hours of operation II). This is because only master discs that pass the ζO inspection sound are sent to the process of manufacturing OX tampers in order to produce mass κ replicas.

However, this conventional method requires approximately 4 hours of time from recording the signal to completing the inspection.
Until that time had elapsed, it was not possible to distinguish between non-defective products and defective products. Therefore, if it is determined that the product is defective after about 4 to 5 hours, it is necessary to manufacture the information recording board again from the beginning, taking the same amount of time, which is extremely inefficient. This is because photoresist is used as the recording layer, and immediately after the signal is recorded, a waste monitor that simultaneously reproduces the recorded signal is not available. . Furthermore, even if the signal recording itself is accurate, if you make a mistake in the development time etc. in the subsequent development process, you will not only end up with a defective product, but also the photoresist will be exposed to natural light. Because of the danger, it was difficult to play by hand in a brightly lit room. Therefore, the natural manufacturing cost was also high.

A method #C of reconsidering such drawbacks and using a material that can be monitored as a recording film is disclosed in US Iil Patent No. 40978, for example.
It is proposed in No. 95. This involves forming an aluminum reflective film on top of the glass master disk, and forming a wave on top of it, which represents a wave* [on the contrary, a dye (fluorescene) with remarkable b-absorption properties]. . When this dye is irradiated with argon laser, kJl bloom is formed because this dye has a remarkable absorption property for the sum of wavelengths of argon laser. When the recording film on which the bits are formed is irradiated with an argon laser that is sufficiently small and has a power that does not sublimate the dye (during recording), the laser beam will not be reflected at the part #C where the bits are formed and the reflective film is exposed. In the part 61c where no bit is formed and the dye remains, the laser beam is absorbed and reflected (or the reflectance is sufficiently small), so the signal is replayed based on the difference in light intensity and the presence or absence of the p bit. It will be possible to assist.

In the case of the O5 method, monitoring is possible, wet development work is not required, and since it has absorbency only for a predetermined wavelength, it can be handled even in a bright room.

However, this method #i had the disadvantage that the sublimation rate of the dye was 7fi, the shape of the bit was not changed, and a recording plate with sufficient SN could not be obtained.

If you are looking for an improved method of this, please refer to Publication No. 87595 dated November 22, 1979, Technical Research Report of Institute of Electronics and Communication Engineers (CPM79-59), ``Real-time laser recording using dye evaporation recording material.'' Disclosed and false. In other words, there are transparent films such as polyester and polyethylene.
is a pigment sensitizer (dye) such as ethyl red, methylene blue, brilliant green, etc. on the base 11M of acrylic etc.
and x) H cellulose (degree of polymerization of about 80) dissolved in a ketone solvent is coated, and a signal is recorded by irradiating the dye sensitizer with a laser beam of a wavelength that has a strong absorption property. It is something.

This method uses not only a dye (dye sensitizer) but also a mixture of chitotetracellulose, which has a fast sublimation rate (due to its self-oxidation effect) and allows recording at low temperatures (low % 6A). If the shape of the bit is only the dye mentioned above, then KM
However, when using the photoresist described above, the shape of the bit is still well arranged and the bit shape is less than 1k%.
Not only /m, but also reaction residue comes out as a horsetail-shaped foreign substance on the recording surface! 11. It was difficult to manufacture an information recording plate with sufficient 8N. Therefore, this method remained at the experimental stage, and in order to mass-produce O-information recording plates as commercial products, IIc had no choice but to adopt the method of using the photoresist described in III.

The present invention was developed in view of the above circumstances, and it improves the latter two methods described above, and eliminates the need for a developing step (2) as in the case of using a photoresist, and enables monitoring. ], the object of the present invention is to provide a method for manufacturing a disk having a weight of 1 kgN, which is sufficient for practical use as a commercial product.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, a group Ill is prepared as shown in the proverb.

One company, seven companies! ! It can be made of, for example, approximately circular glass with a polished surface. Of course, if you only want to record information on a 100+ nt recording board and produce a large number of replicas from it, the substrate 1 can be made of synthetic resin such as polyester or acrylic. So, did you clean the board 1? 1, and then 0 on the surface, for example #! , a reflective film made of aluminum or the like is coated with a predetermined O1i material (e.g. z
ooλ to 400A)K is formed. If this thickness is too thin, it will not be possible to obtain a sufficient amount of reflected light for monitoring, and if it is too thick, functional space will not be produced, but material will be wasted. When the reflective film 2 is formed of silver with a thickness of about 200λ, the readout film 9?
On the reflective film 2, which had a reflectance of 80 to 1185X, an information recording layer 3 containing a dye sensitizer and nitrocellulose is formed. Nitrocell gastrointestinal tract as OJi family if a' to le a-xi) 19
7 or above is recommended. If the content of 1L cellulose is low, reaction residues will be scattered on the recording surface and it will not be possible to obtain a sufficient 1 ksN. Therefore, in order to obtain an information recording plate that can be used practically. #isa cellulose to 9
The number average degree of polymerization of nitrocellulose is 8o to 95 (R in JI8).
8 and 2 and 1) $li! This is the degree of polymerization of 0)
If it is too small, the shape of the bit 0 will not be neatly arranged, and if it is too large, the viscosity will be too strong, making it difficult to uniformly coat the recording layer 3 to a predetermined thickness. This linter is nitrified by the sulfur/nitrogen mixture method or other methods, and the degree of nitrification is at least 13X or more, preferably 1[32X or more.If the degree of nitrification is insufficient, the recording beam If the power is not increased, the bit cannot be formed, and if the power is increased too much, the shape of the bit will be different. Therefore, as will be described later, the degree of nitrification was increased to a certain extent, and the nitrocellulose obtained in this manner was compared to 1111111
(11e ef xylene or a mixture of xylene and ethyl ryu-shinorp acetate) K dissolved, and if kept, α2 voice mo
Pass through a second filter.

In addition, N-ethyl-Noxyethylaniline is used as the dye sensitizer.
s agent kssiK, mAf;l,.

After that, the organic solvent in which the nitrocellulose was dissolved and the organic solvent in which the dye sensitizer was dissolved were mixed with #C so that 2) the weight ratio of the wt lance and the dye sensitizer became a predetermined weight fraction. death,
Furthermore, 1 gK of a compound of nitrocellulose and dye sensitizer
An organic solvent is added to the mixture at a ratio of, for example, 4.C, and the mixture is heated to 40°C and shaken for about 4 hours. This liquid is again subjected to the process 1 to form a material for the information recording layer 3 at a ratio of 1:1.

KIIIL to make ζo material, light transmittance ag2 when changing the weight fraction of nitrocellulose and dye sensitizer and 0
It changes as shown in the figure. In the case of decoy, AFi 0 weight car is set to 94LO and BFi 90.
O vs. 1αO, C is 86.5 vs. 115, Dhso vs. 20
This is the case. In either case, the wavelength is from 440 nm to 5
It has significant light absorption in the 39 mm range 1q, but
As the content of the dye sensitizer is increased, the degree of this phenomenon becomes more significant. For example, as shown in CK, the weight fraction is 86.5 to 13.5.
Then, its kinematic viscosity is 3.6est at 25° C.9, resulting in a transmittance of about 35X (therefore an absorption rate of about 65X) for an argon laser whose wavelength is 456.1 nm.

This material is spin-coded onto the reflective film 2 to form an information recording layer 3.
For example, a material of 10 ee to form 6 is dropped onto the reflective film 2, rotated at 250 rpm for 11 seconds, and then
By rotating at c600 rpm for 61 seconds, an information recording layer 3 having a thickness of about 2506λ can be formed.

When spin coating is performed, the information recording layer 3 can be formed uniformly by rotating the substrate 1 on which the reflective film 2 is formed, first at a low speed and then at a higher speed.

After forming the information recording layer 3, it is baked at about 80° C. for 15 to 20 minutes to evaporate the organic solvent and cooled after lI. If any organic solvent remains, use extra power to 41 pH to evaporate it during signal recording.If the power during recording is insufficient, make sure to mold the bits sufficiently. This also causes reaction residue to appear. Also, depending on the dye sensitizer, the organic solvent evaporates and dries, and at that point it becomes non-uniform and becomes uneven, but this is not the case with N-ethyl-Noxyethylaniline. celebrate.

The process then proceeds to a so-called mass-melting process in which the V signal formed in the information recording medium M3 is recorded.

For example, the master disc on which the information recording layer 3 is formed is at a linear velocity of #l.

For example, an audio signal can be converted into an EFM (Eight
t-To-Fourteen Mod/ation
) is modulated with a signal and irradiates the information storage layer 3 from the information storage layer 3 onto the information storage layer 3. Then, the portion irradiated with the laser beam is sublimed by the heat because the dye sensitizer has a significant absorption property for the wavelength of the argon laser.

Furthermore, since nitrocellulose is mixed, due to its self-oxidation effect, the nitrocellulose also sublimates, while the sublimation of the dye sensitizer is also promoted, forming bits 4 as shown in Figure J1. A portion 5Fi that is not irradiated with the argon laser remains. This sublimation phenomenon will not occur unless light in the wavelength band in which the dye sensitizer exhibits significant absorption is irradiated at a level exceeding the specified darkness value9. Therefore, not only the mastering process but also the storage and handling of the master disc should be done in a bright room. It is possible.

When the master disc itself on which the signal was recorded in this way is run through a regenerator using a helium-neon laser with a power output of approximately 0.3 mW on the information recording layer 3 and a wavelength of 631L8mm, it can be reproduced. Met. SoO regeneration J [m is not certain, but the dye sensitizer used has almost no absorption for the wavelength of the helium neon laser, so it is at least a bit off) in 4. If the amount of reflected light increases and the amount of reflected light decreases because it is absorbed by the remaining part S, it is not a JIMK base (of course, if an argon laser is used for reading, it is based on this 11111 (reproduction is possible). Probably bit 4#c Diffraction or interference occurs in the remaining part 5) The amount of reflected light is reduced, and in the remaining part 5, it is reflected! I
This seems to be due to the fact that the amount of reflected light increases due to X2.

- It is practically important that even if the argon laser is used, it can be regenerated using a helium-neon laser.However, in the case of an argon laser, a cooling device, etc. is required, resulting in a large amount of waste. However, helium-neon lasers can be used in consumer regenerators (currently on the market). This means that the information recording plate of the present invention can be further reproduced using a zero-wavelength semiconductor laser.

The weight fraction of nidotetracellulose and dye sensitizer was 86.5.
In the case of 13.5, the master disk recorded by changing the recording power on the information storage layer 3 is played back as it is with a playback machine using a helium neon laser, and the level of the playback RF signal and the position of the eye pattern are When the change in the average error rate per -30 seconds (average for about 10 to 50 minutes) was examined, the results were as shown in the following table.

On the other hand, if the photoresist F is developed to form bits and then the entire surface of the photoresist is coated with a reflective metal and the nine original disc is reproduced, the RF level will be between 1000 and 1300.
mVpp, eye pattern is in the center or slightly below center, and error rate is in the 10s. That is, in the information recording plate according to the present invention, if the recording power is selected to be moderate (2.8 to 0.0 mW), the error rate can be improved by one order of magnitude (compared to when the conventional 7-otoresist is used).

This means that the signal is recorded more accurately. Furthermore, even if you play it immediately after mastering, it will be 46
(A raw RF signal level of lnW to 550mW can be obtained, and the signal readout is also excellent since the turn position is slightly below the center.) Not only can it be monitored, but it can also react when forming bits. Residue comes out and information recording layer 3
I have never had it scattered on the top, so it is sufficient for practical use & SN
Therefore, it can be used as a single information recording board for convenience.

Also, vapor deposition on the information recording silver layer 3,
A metal such as silver is coated as a conductive layer (by electroless plating, etc.), and then a metal such as nickel (by electroforming, etc.) is coated on top of it as a conductive layer, and then a metal such as nickel is coated from the jj board. The metal can be peeled off and used as a stamper. (Of course, you can use this metal disc as a master disc to obtain a % mother disc, and then create a submaster disc and use it as a stunt pigeon.

) Replicas mass-produced from a stamper can be made into information-recording silver plates that can be read by optical, capacitive, piezoelectric, etc. pickups by selecting appropriate materials. .

Furthermore, the master disc according to the present invention can easily be used during mastering or immediately after mastering is completed (if it is found that the mastering has failed by monitoring, mastering is immediately stopped, and an organic solvent is poured over the recording layer 3). 3 can be removed, and after shaking off the organic solvent, the Otori 11#I
C. A new recording layer 3 can be formed immediately. In the case of photoresist O, after polishing the substrate again, the surface of the substrate became rough because the photoresist was not coated.
Considering that N becomes worse, the present invention O information record 1ji
I& means more practical. Xylene may be used as the organic solvent in the case of 0, but it is preferable to use it quickly due to the drying speed.
In addition, in the main generation IIc, if a monitor is not required, the recording layer 3 is formed directly on the base IIIK.It is limited to audio signals, video signals, etc. #i&<%The information recording& is a video disc.

It can also be applied to other than PCM audio discs.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of an information recording silver plate, and FIG. 2 is a graph showing changes in transmittance with respect to a wave pattern. 1.- one base 2... reflective film 3...-
・Information recording layer 4...Bit 5...
Remaining patent applicant Pioneer Corporation Figure 1 Figure 2 Nagato Hara (Lem)

Claims (1)

[Claims] (1) 1 cellulose having a predetermined number average degree of polymerization is 97
Nitrocellulose is obtained by nitrifying the material containing % or more to a predetermined degree.The nitrocellulose and the dye sensitizer are dissolved in an organic solvent at a predetermined weight fraction, and The organic solvent in which the dye sensitizer is dissolved is filtered, and the filtered organic solvent is coated on a substantially circular substrate as an information recording layer (by a signal containing at least one of an audio signal or a video signal). , manufacturing a disk by modulating a laser beam with a wavelength at which the dye sensitizer exhibits significant absorption, and irradiating the modulated laser beam onto the information recording silver layer to form bits. Method. (2) A reflective film for reflecting the laser beam is formed on the substrate, and the information recording silver layer is formed on the reflective film O. Disc manufacturing method. (3) The above-mentioned Nitrocell chloride and the above-mentioned dye sensitizer are separately dissolved in the organic solvent, and each is mixed in a predetermined weight fraction. A method for manufacturing a disk according to claim 11 or 1112. (4) The organic solvent in which the nitrocellulose and the dye sensitizer are dissolved separately is filtered through a mixing spoon. Disc manufacturing method. (5) The above patent claim 011 whose percentage image is that the dye sensitizer is &;tN-ethyl-Noxyethylanidan
11 Arithmetic 1 term. A method for manufacturing a disk as described in IE Sections 2 and 13, Paragraph 4. {1. The method for manufacturing a disk according to claim *S*, wherein the sheath beam is an argon laser beam. (7) Patent i! characterized in that the nitrification of the nitrocellulose is 13X or more! tl irises 1st term, 2nd term. Chin Section 3. A method for manufacturing a disk according to Iris section 4, Iris section 5, or Iris section 6. (8) The number average polymerization f of the above cellulose is 80 to 95
Claims 1, 2, and 3 are characterized in that: Chin 4, Iris 5. Section 6 and fill-in 7. i
[Method for manufacturing the disc described. (9) Paragraph 1 of the above patent claim, wherein the organic solvent is xylene or xylene and ethylseron rub acetate. Section 2 of Chin. Section 3, @ Section 4. Section 5 1161i1171i or Section 8
Method for manufacturing the Dista described in Section. (4) Nitrocellulose is obtained by nitrifying a material containing 97X or more of lullose in IIL having a predetermined number average polymerization degree to a predetermined degree, and adding the nitrocellulose and a dye sensitizer to a predetermined weight. Dissolve the cellulose in an organic solvent. straining the organic solvent in which the dye sensitizer and the dye sensitizer are dissolved;
A κ-reflecting film is formed on a substrate made of approximately circular glass, and the filtered organic solvent is subjected to Svinco F, and a signal κ containing one of the audio or video signals is mixed with the dye. The sensitizer produced laser beam ▲ of a wavelength exhibiting a 1 iL characteristic at -1, and the modulated laser beam ▲ was irradiated with κ onto the information recording layer to form a bit. A conductor layer is formed on the information recording layer, a metal film such as nickel is formed on the wrinkled conductor layer, and the metal film is peeled off to transfer the recorded information formed on the metal film to another member. A method for manufacturing a disc, characterized by: Axis The above conductive layer is deposited or sputtered. The above-mentioned patent claim 01ialK is characterized in that it is formed (by electroless plating, etc.) and formed by upper metal II4IIXIIi electroforming.
Manufacturer of the disc described in item 10, 1.