KR20030012588A - a manufacturing method of optical discs with color - Google Patents

Abstract

PURPOSE: A method for manufacturing a color optical disc is provided to mix coloring agents having various colors with the material of an optical disc to produce a color optical disc with excellent UV blocking effect and thermal characteristics. CONSTITUTION: Photoresist is coated on a glass substrate and a laser beam is irradiated on the photoresist, to fabricate a glass master on which pits and lands are formed. Nickel is plated on the surface of the glass master and separated from the glass master, to form a stamper. The stamper is attached to a mold, polycarbonate resin and a coloring agent are mixed with each other and injection-molded, to form a color substrate. An aluminum film is coated on the surface of the color substrate to form a reflection layer. A UV-hardened resin is coated on the surface of the reflection layer to form a protection layer. A label is printed on the protection layer.

Description

{A manufacturing method of optical discs with color}

The present invention relates to a method for manufacturing a color optical disk, and specifically, by mixing a colorant having various colors with a polycarbonate resin, which is a substrate raw material of an optical disk, and manufacturing an optical disk by injection molding the same, thereby maintaining physical properties of the polycarbonate. In addition, the present invention relates to a method of manufacturing a color optical disc, which has excellent UV blocking effect and good thermal characteristics, so that data is not damaged from ultraviolet rays or external shocks when recording various data such as music or video onto the color optical disc.

In general, optical discs are a storage medium for recording information on a disc with light. The optical discs store information by changing light transmittance, reflectance, phase, polarization, and the like, and store the change in light (laser). Technology) to get information.

CD-DA (music CD), the leader of optical discs, first appeared in 1978, and since 1982, when Philips and Sony made RedBook standards, they have become popular. It has rapidly grown into a digital storage medium due to its huge storage capacity and excellent reproducibility in terms of audio, data and other uses compared to magnetic media.

Such optical discs include LD (Laser Disc), CD (Compact Disc), DVD (Digital Video Disc / Digital Versatile Disc), and the most commonly used CDs are CD-DA (CD-Digital Audio), CD- CD (Read Only Memory), CD-R (CD-Recordable), CD-RW (CD-Rewritable).

CD-DA or CD-ROM is a reproducible medium that cannot be recorded, and has continuous pits and lands formed in the form of grooves therein. In other words, the data is already stored. Looking at the structure, the label layer for brand printing, the protective layer for protecting the reflective layer, gold, silver or aluminum or copper and the reflective layer for reflecting the laser during reproduction, the shape It consists of a polycarbonate board | substrate to hold | maintain.

According to the principle of the CD for reproduction, the laser beam is not reflected well in the pit which is a portion deformed by using the laser, and the laser beam is well reflected in the land having the original property other than the pit. To interpret the signal. In this way, the original signal is reproduced by dividing 0 and 1 by converting and amplifying different reflection amounts into electrical signals and comparing them with a predetermined value.

CD-Rs or CD-RWs are unrecorded storage media, which are empty forms having no pits and lands therein, and have grooves formed to guide users to record desired information. In other words, after recording, pits and lands are formed as recording is possible, and recording and playback using a separate recorder and recording S / W are used to make various types of CDs or to use them for backup.

The structure consists of a label layer, a protective layer, a reflective layer made of gold or silver, a polycarbonate substrate, a groove which is a guide groove of the laser, and an organic dye layer (recording layer) which increases the laser output between the substrate and the reflective layer. Cyanine, Phthalocyanine, and Azo may be used for the organic dye layer.

According to the principle of the recording CD, the beam emitted from the laser pick-up of the recorder (converts sound or light into radio waves) passes through the substrate under the rotating CD-R / RW and is grooved in the next organic pigment layer. The signal is condensed or not continuously, and the dye of the organic dye layer is recorded by forming a deformed pit and a land that is not deformed while receiving a predetermined energy or more with a laser.

DVD (Digital Versatile Disc) is called the next generation digital video disc because of its high quality, high sound quality, high capacity, and multi-functionality. It is used not only for video but also for a wide range of applications such as DVD-AUDIO, DVD-RAM, DVD-ROM, etc. .

The basic structure of such a DVD is the same as that of a general music CD. In the case of a DVD, the pit is formed at a denser density on the surface of the disc, thereby allowing more data to be stored.

In addition, since DVD can write not only one side of a disc but also both sides, and has two layers on one side to record different data for each layer, it has an excellent capacity for data. It became possible.

The DVD is divided into DVD-Video, DVD-R / RW, DVD-ROM, and DVD-RAM, among which DVD-R / RW, like the CD-R / RW, DVD-R sequentially records data once DVD-RW can write and erase data multiple times, and is compatible with DVD-ROM. DVD-RAM, like DVD-RW, can write and erase data many times over, but it is not compatible with DVD-ROM.

The biggest difference between the DVD and the CD is that the DVD is made by joining two sheets. That is, a CD has a thickness of 1.2 mm and a DVD has two substrates having a thickness of 0.6 mm, which is half that of a CD. This method is selected by reducing the influence of the warping of the optical disc, increasing the storage capacity, and considering the compatibility with the CD.

The DVD bonding method is a hot melt method and a UV resin method. In the former case, as in the case of a conventional laser disc, when one side is finished, the disc needs to be ejected and flipped over again. Although not commercially available, two boards can be read from one side.

On the other hand, the CD manufacturing method of the conventional optical disk is described as follows.

Looking at the manufacturing process of the conventional CD, the step of applying a photoresist to the glass plate and then photosensitive with a laser to produce a glass master is formed with pits and lands; Plating a nickel on the surface of the glass master and separating the same to prepare a stamper; Attaching the stamper to a mold and injecting the polycarbonate into the mold, followed by injection molding to manufacture a substrate on which pits are formed; Coating an aluminum reflective film on the substrate to form a reflective layer; Forming a protective layer by coating a protective film on the aluminum reflective layer; And printing a label on the protective layer.

In addition, looking at the manufacturing process of CD-R / RW, which is a recording CD, after the photoresist is applied to a glass plate, the photoresist is laser-produced to produce a glass master having a groove formed thereon; Plating a nickel on the surface of the glass master and separating the same to prepare a stamper; Attaching the stamper to a mold and injecting the polycarbonate into the mold, followed by injection molding to manufacture a substrate; Cooling the substrate; Coating an organic dye on the cooled substrate to form a recording layer; Forming a reflective layer by coating a reflective film on the recording layer; Coating a protective film on the reflective layer to form a protective layer; And printing a label on the protective layer.

By the way, when storing various data such as music or moving pictures by using a recording CD manufactured by the prior art, that is, CD-R / RW, there is a drawback that the recordability is not good because the CD has low thermal characteristics.

In general, the material of the CD substrate is made of transparent polycarbonate, and the CD made of such a polycarbonate substrate has a low UV blocking effect, so that the recording layer is destroyed due to heat change due to ultraviolet rays when exposed to sunlight, and thus there is a high possibility of damaging data. There was this.

For example, if you store the disc for a long time in a car or in the sun, the CD-R is organic in color and weak in UV light. The contrast between the and the lands disappears, which eventually results in the CD-R's inherent functionality.

In addition, the surface of the CD is often peeled off or scratched due to inadvertent use of the user. In the CD, the reflective layer and the protective layer have a great influence on the life of the CD. If the surface of the CD is damaged, the reflective layer is a metal layer. If the laser beam is not properly reflected, the data of the part cannot be read and there is a fear that all the stored data will be lost.

As described above, in the case of a CD manufactured by the conventional method, there is an inconvenience that the user must manage with special care so as not to be exposed to sunlight and damage from external shock.

In addition, the conventional CD-R / RW are all limited to a uniform color, for example, gold or silver reflected by a reflective film, which has the disadvantage that it cannot be distinguished by color according to the contents and product characteristics stored in the CD. There was a big flaw, and this was also the case with DVD.

However, the optical disc is a high-precision medium for recording a large amount of data and reproducing it, and since the fine dust is directly connected to the defect of the product so that the cleanliness level inside the manufacturing plant requires a class level of 100, so far, when manufacturing the optical disc It has been contraindicated to mix any foreign matter with the raw material.

In addition, in order for the laser to recognize the data accurately, the light distortion is small and the transmittance is high and the reflectance is high.In this regard, the colorant input may intensify the light distortion and lower the reflectance. I had no idea about the manufacture of optical discs, and even failed to produce color optical discs.

However, color discs are necessary not only for actively responding to the taste of modern people who value fashion but also for marketing purposes such as important functions that distinguish products, such as secret classification, age-appropriate use of products, and classification such as usage. Was.

Accordingly, the present invention has led to the development of color optical discs with no defects in the quality of disc products even when mixed with a polycarbonate as a raw material.

The present invention was developed in order to solve the above problems, by mixing a colorant of various colors to the polycarbonate resin which is a raw material of the optical disk substrate, while maintaining the physical properties of the polycarbonate and at the same time excellent color of the optical disk It is an object to provide a manufacturing method.

Another object of the present invention is to diversify the color of the optical disk to easily distinguish the characteristics of the contents contained in the disk and at the same time the appearance is gorgeous to meet the consumer's purchase needs.

1 is a process chart showing a manufacturing method of a color optical disk according to a preferred embodiment of the present invention.

2 is a process diagram showing another embodiment of FIG.

3 is a process chart showing a manufacturing method of a recording color optical disc according to the present invention;

4 is a process diagram showing another embodiment of FIG.

In order to achieve the above object, a method of manufacturing a color optical disc according to the present invention comprises: preparing a glass master having pits and lands formed by applying a photoresist to a glass plate and irradiating a laser beam; Preparing a stamper by plating nickel on the surface of the glass master and separating the plate; Attaching the stamper to a mold, and injection molding a mixed material of 96.5 to 99.9 wt% of a polycarbonate resin and 0.01 to 3.5 wt% of a colorant to manufacture a color substrate; Forming a reflective layer by coating an aluminum film on the surface of the color substrate; Forming a protective layer by coating an ultraviolet curable resin on a surface of the reflective layer; Printing a label on the surface of the protective layer.

In addition, the method for manufacturing a recording color optical disk according to the present invention comprises the steps of: applying a photoresist to a glass plate and then irradiating a laser beam to produce a glass master having a groove formed thereon; Preparing a stamper by plating nickel on the surface of the glass master and separating the plate; Attaching the stamper to a mold, and injection molding a mixture of polycarbonate resin 99.5 to 99.9 wt% with 0.01 to 3.5 wt% of a colorant to prepare a color substrate; A cooling step of cooling the color substrate; Coating an organic dye on a surface of the cooled color substrate to form a recording layer; Coating gold or silver on the surface of the recording layer to form a reflective layer; Forming a protective layer by coating an ultraviolet curable resin on a surface of the reflective layer; Printing a label on the surface of the protective layer.

In addition, the colorant is characterized in that it is selectively used from anthraquinone to give a purple, anthraquinone or perinone to give a red color, lactones to give an orange color, anthraquinone or coumarin to give a yellow color.

Hereinafter, the manufacturing method of the color optical disk of the present invention in detail according to the process as follows. 1 to 4 show a process diagram showing a manufacturing process of a color optical disc and a recording color optical disc according to a preferred embodiment of the present invention.

According to the drawings, a method for manufacturing a color optical disk according to the present invention is to install a color mixing machine at the inlet of the raw material inlet in the process of injection molding the polycarbonate, which is a raw material of the disk substrate during the manufacturing process of the conventional optical disk, together with the polycarbonate and the coloring agent at once It is characterized in that the injection molding and mixing with each other after the injection. This will be described in detail below.

First, a manufacturing method of a color optical disc will be described.

First step: manufacturing glass master

Converts analog signals to digital signals to produce a master tape that contains data.

Subsequently, the photoresist, that is, photoresist, is uniformly applied to the surface of the polished glass plate and dried, and then the digital signal of the master tape is modulated according to the disk type to expose the glass plate coated with the photoresist with a laser beam. do. At this time, if the part that receives the laser beam is not melted and the part that is not received is developed using the principle of melting, a glass master is formed by forming a number of small holes in the glass plate so that it can be divided into 0 and 1 data. Is prepared.

Second step: stamper manufacturing step

A stamper is a metal plate used for mass copying a disk, and a stamper is manufactured using the glass master manufactured in the first step.

That is, since the glass master is electrically insulated, the surface is coated with nickel (Ni) to form a conductor, and then a father is manufactured. Then, after the nickel plating is performed on the father, the mother is separated to produce a mother. The stamper is manufactured by separating the mother after nickel plating.

Third step: colorant mixing step

Polycarbonate resin is mainly used as a raw material for manufacturing an optical disk substrate. As a characteristic component of the present invention, a polycarbonate resin is mixed with a colorant in the form of powder or pellets. It will be used as

That is, the polycarbonate resin in the raw material tank and the colorant in the dyeing tank are transferred to a color mixer and uniformly mixed so that the colorant is uniformly dispersed in the transparent polycarbonate resin and then transferred to the injection molding machine, which is the next step.

Alternatively, when the polycarbonate resin is introduced through the raw material inlet, a predetermined proportion of the colorant may be added together to the injection molding machine to uniformly mix and uniformly disperse the colorant in the polycarbonate resin and simultaneously perform injection molding (see FIG. 2).

At this time, the mixing ratio is 96.5 to 99.9 wt% of polycarbonate resin and 0.01 to 3.5 wt% of a colorant, and the mixing method uses an extrusion screw method at a temperature of 300 to 330 ° C.

As the colorant, it is preferable to use an anthraquinone purple colorant, anthraquinone or perinone red colorant, lactone orange colorant, anthraquinone or coumarin yellow colorant, or the like. However, the present invention is not limited thereto, and other colorants having the same effect may be used.

These colorants are excellent in color fastness and light resistance, and have a vivid color tone.

Fourth step: forming substrate

When the stamper obtained in the second step is attached to the mold, and injection molding is performed in accordance with the disc specification using the mixed raw material obtained in the third step, pits are formed on the surface and a polycarbonate substrate having various colors is manufactured. . This same method is repeatedly performed to manufacture a color substrate.

In addition, as a machine for injection molding the mixed material, Krauss Maffei or Nestel Diskjet is preferably used, but is not limited thereto.

The fifth step: forming a reflective layer and a protective layer

The reflective layer is formed by coating an aluminum reflecting film so that a laser beam for picking up data can be reflected on the surface where the pit of the color substrate obtained in the fourth step is formed.

Subsequently, a protective layer is formed by coating an ultraviolet curable resin film, preferably a lacquer, on the reflective layer so that the aluminum reflective layer is protected from external impact without being oxidized.

Step 6: Printing and Packaging Labels

Discs that have passed the inspection of defects are printed on the protective film and packed in a case.

Next, the manufacturing process of the recording color optical disc will be described.

First step: manufacturing glass master

When the photoresist is applied onto the glass plate and the grooves are condensed on the glass plate with a laser, the exposed portion of the laser is not melted by the developer and the unexposed portion is melted to form a glass master having grooves formed on the glass plate.

Second step: stamper manufacturing step

Nickel plating is then performed on the surface of the glass master obtained in the first step by sputtering to separate nickel, thereby producing a stamper made of nickel.

Third step: colorant mixing step

It is the same as the colorant mixing step in the manufacturing process of the color optical disk.

Also, in this step, the polycarbonate resin and the colorant are mixed uniformly with each other by a color mixer and then injected into an injection molding machine (see FIG. 3), or a polycarbonate and a colorant having a predetermined ratio are simultaneously introduced into the injection molding machine. There is also a method (see FIG. 4). At this time, the mixing ratio is 96.5 to 99.9 wt% of polycarbonate resin and 0.01 to 3.5 wt% of a colorant.

Fourth step: forming substrate

The same as the substrate forming step in the manufacturing process of the color optical disk.

5th step: cooling step

Since the temperature of the color substrate obtained in step 4 is very high, about 110 ° C., the cooling process is performed so as to be a temperature suitable for the organic dye coating in the recording layer forming step described later.

Step 6: forming the recording layer

The organic pigment is coated on the surface of the cooled color substrate obtained in step 5, and in this process, dye solutions such as cyanine, phthalocyanine, and azo are used. It is applied uniformly to form a recording layer (organic dye layer).

At this time, the method for coating the organic pigment on the color substrate is to sprinkle the dye solution in the center of the color substrate and then spin at a high speed (centrifugal force) to apply the dye solution evenly on the front surface of the color substrate.

Step 7: forming the reflective layer and the protective layer

A reflective layer of gold or silver is coated on the color substrate coated with the organic dye obtained in the sixth step so that the laser beam is reflected.

Subsequently, the protective layer is formed to protect the recording layer and the reflective layer, in the same manner as the manufacturing process for the color optical disc.

Step 8: Label Printing and Packaging

It is the same method as the manufacturing process of the said color optical disk.

On the other hand, the physical properties required for using polycarbonate as a light storage substrate include low optical distortion, low birefringence, high transparency, and good numerical dimensionality. Stability, high mechanical strength, high purity (freedom from impurities), disc mold and good mold surface reproduction, and good processing stability are required.

In particular, the optical disc is a high-precision medium for recording and reproducing a large amount of data. In order for the laser to recognize the data accurately, the distortion of light must be small.

Therefore, in the process of mixing with the polycarbonate, the colorant used in the present invention should not inhibit the physical properties required for the polycarbonate substrate unlike the general dyes.

That is, even if the colorant having various colors of the present invention is mixed with the polycarbonate, there should be no distortion of light and no difference in physical properties as compared with the conventional transparent polycarbonate substrate.

This will be described in detail through the examples.

Example

In the present invention, in order to express the color of the disk, 96.5 to 99.9 wt% of a polycarbonate resin and 0.01 to 3.5 wt% of a colorant are injection molded to prepare a substrate having various colors, and then manufactured as an optical disc. Physical properties were tested and the results are shown in Table 1.

In addition, the product name used as the colorant in the embodiment of the present invention, the violet colorant anthraquinone is violet thial (Violet TR), the red colorant anthraquinone is red TVG (Red TBG), the orange colorant lactone is orange Orange LGP, a yellow colorant, coumarin, used Yellow 8GF, which is manufactured by Ciba Specialty Chemicals.

(1) Polymer Soluble

The colorants must be well dissolved in the polycarbonates in order to express the color of the disc evenly when the respective coloring agents are mixed with the polycarbonates. The solubility test according to the German Industrial Standard DIN (Deutsche Industrie Norman) 55976 shows that The colorants were all evenly dispersed in the polycarbonate.

(2) Heat stability

In general, optical discs are molded at a temperature of 310 to 330 ° C., and since the substrate is manufactured at a very high temperature, the properties of the colorant should not be deformed below the reference point or lose their physical properties at such a high temperature. In particular, in the case of a recording disk, data is recorded by using a laser beam having a strong wavelength. As the heat resistance temperature of the recording disk is increased to 300 ° C., the organic color of the recording layer is melted to record the data. It should not cause a change in appearance.

In the case of the colorant mixed and used in the substrate of the present invention, since the thermal stability is shown at a temperature of 360 ° C, it can be seen that the resistance to heat is high.

At this time, the thermal stability is the temperature when the color change of the colorant at the maximum temperature is not greater than the fourth grade of ISO 105 A021-5 Gray Scale, the gray scale is different from pure white to black concentration Refers to 10 levels of gray tones.

(3) Lightfastness

The light resistance was classified into 8 grades through the Xenon Lamp exposure test according to ISO 105 B02, and the higher the value of 8 out of 10, the better the light resistance, and the light resistance of each colorant was good between 7 and 8. .

(4) refractivity & reflectance

If the laser reads from or writes to the disc, the error should not be caused by anomalies or reflections. Discs prepared in accordance with the present invention were each tested with CDCATS CA3, and found to be significantly better than the specular reflectance.

Here, the standard reflectance is 70% or more for CD and 65% or more for CD-R / RW, which is according to Red Book or Orange Book specifications of Philips and Sony.

Thus, as shown in the above embodiment, it was found that the physical properties of the color optical disc according to the present invention are all good.

Next, Table 2 shows the results of experiments on the transmittance of the disk.

(5) Transmission

In order to read or write data stored on the disk, the laser beam must be transmitted through the disk well, and the optical disk manufactured by mixing the colorants of the present invention with polycarbonate, respectively, within a wavelength range of 200 to 1100 nm. The transmittance was tested, especially in the range of 60 ~ 90% at 680 ~ 780nm such as the laser beam wavelength range of general DVD player or CD player.

At this time, the test method was measured using a Perkin Elmer Lambda 900 spectrometer.

Therefore, the color optical disk manufactured by mixing the colorant according to the present invention to the polycarbonate resin improves the recordability of data, protects the product by blocking ultraviolet rays (UV), and highlights the distinctiveness of the product due to the color of the color. Can be.

In addition, in the present embodiment, only the manufacturing method of the CD and the CD-R / RW are described, but the present invention can be applied to the DVD as a matter of course.

As described above, the method for manufacturing a color optical disc according to the present invention has been described with reference to the illustrated drawings, but the present invention is not limited by the embodiments and drawings disclosed herein, and various modifications may be made by those skilled in the art within the scope of the technical idea of the present invention. Of course, modifications can be made.

As described above, the present invention has developed a color optical disc after breaking the notion that color insertion is difficult in the optical disc. According to the manufacturing method of the color optical disc of the present invention, in the manufacturing method of the optical disc, the polycarbonate resin, which is a raw material of the disc substrate, By mixing colorants with various colors and manufacturing optical discs using injection-molded color substrates, the thermal properties of the discs are good, making them recordable, and the UV protection effect from colorants is excellent. There is little concern that the recording layer may be destroyed due to thermal changes upon exposure, thereby extending the life of the optical disc.

In addition, the color of the optical disc can be manufactured in various ways, so that the characteristics of the disc can be distinguished and used, and the contents of the disc can be easily typed. The color of the disc can be classified not only in the company's confidential information, but also for video. Even discs can be used efficiently because they can be distinguished by age.

In addition, the appearance of the disc is gorgeous, it can satisfy the purchase needs of consumers, including young people to pursue fashion.

In addition, it can be manufactured in the same manner as a conventional optical disk manufacturing process except that a color mixer for mixing polycarbonate and a colorant, which are raw materials of the substrate, can be manufactured in the same manner as the conventional optical disk manufacturing process.

Claims (3)

Applying a photoresist to the glass plate and irradiating a laser beam to manufacture a glass master having pits and lands formed thereon; Preparing a stamper by plating nickel on the surface of the glass master and then separating the glass master; Attaching the stamper to a mold, mixing 96.5 to 99.9 wt% of a polycarbonate resin and 0.01 to 3.5 wt% of a colorant, and then injection molding to prepare a color substrate; Forming a reflective layer by coating an aluminum film on the surface of the color substrate; Forming a protective layer by coating an ultraviolet curable resin on a surface of the reflective layer; And printing a label on the surface of the protective layer. Applying a photoresist to the glass plate and then irradiating a laser beam to produce a grooved glass master; Preparing a stamper by plating nickel on the surface of the glass master and separating the plate; Attaching the stamper to a mold, and mixing the polycarbonate resin with 99.5 to 99.9 wt% of 0.01 to 3.5 wt% of a colorant, followed by injection molding to manufacture a color substrate; Cooling the color substrate; Coating an organic dye on a surface of the cooled color substrate to form a recording layer; Coating gold or silver on the surface of the recording layer to form a reflective layer; Forming a protective layer by coating an ultraviolet curable resin on a surface of the reflective layer; And a label printing on the surface of the protective layer. The method according to claim 1 or 2, The colorant is a method for producing a color optical disc, characterized in that any one selected from purple anthraquinone, red anthraquinone or perinone, orange color lactone, and yellow anthraquinone or coumarin.