JP2005096356A - Optical recording medium substrate and method for dissociating its thin film material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical recording medium substrate which can dissociate the substrate and its thin film material promptly, economically, and effectively without generating contamination and apply it in the recycling treatment process of an optical recording medium and a method for dissociating the optical recording medium substrate and its thin film material. <P>SOLUTION: By destroying a metal reflection layer of the optical recording medium by using the characteristics of the selective action of electromagnetic waves and concentrating energy in a short time and dissociating it from another layer by the absorbed energy, a substrate layer of the original recording medium and a thin film layer are recovered promptly and effectively without generating contamination. Its original physical properties can be maintained and used for reusing a high value. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for dissociating an optical recording medium substrate and a thin film material thereof, in particular, by placing the optical recording medium in an electromagnetic wave environment, destroying the metal reflective layer of the optical recording medium using electromagnetic wave concentration energy, and absorbing the energy. The present invention relates to an optical recording medium substrate and a method for dissociating the thin film material, in which the substrate material and the thin film material are separated quickly from each other.

  Currently classified general optical recording media can be broadly classified into ROM optical discs, write once optical discs, and rewritable optical discs when classified according to their physical properties. Taking a ROM optical disk as an example, a general CD is a kind of ROM optical disk, and is formed by forming a reflective layer and a protective layer in order on a substrate layer. A write-once optical disc includes a general CD-R, which is formed by forming a recording layer, a reflective layer, and a protective layer in order on a substrate layer. A rewritable optical disc includes CD-RW, which is formed by forming a dielectric layer, a recording layer, a dielectric layer, a reflective layer, and a protective layer in order on a substrate layer.

  All of these current optical disc products all have a substrate layer and a thin film layer that constitute the main body of the optical disc. Of these, the substrate layer that constitutes the main entity of the optical disc is a laser beam used for data reproduction or data recording. Is made of a material such as polycarbonate resin, acrylic resin, polyolefin resin, or epoxy resin.

  However, optical discs such as those described above have been used in large quantities, and with the increase in demand, disposal after use has become a problem. This includes all the waste that needs to be treated, including those that were rejected in the final final inspection process, obsolete surplus items, and pirated items that must be discarded.

  Regarding the disposal of the optical disc, the methods employed so far as the disposal method of the optical recording medium include a method of dusting and filling the waste optical recording medium and a method of burning the waste optical recording medium. In the former processing method, it is difficult to select a place to be buried, and in particular, there is a problem that a metal contained in a thin film layer of an optical recording medium to be discarded causes secondary contamination. Moreover, in the latter processing method, a special incinerator is required, and if the waste air after incineration is not treated, it cannot be discharged, and the processing cost and speed are not ideal. Also, from the viewpoint of resource recycling, both are disadvantageous in recycling subsequent resources, and the entire substrate, such as the PC piece of the substrate layer of the waste optical recording medium, is recovered and used again as the substrate of the optical recording medium. In the case where a plastic with a relatively low economic value is produced even after recycling, the optical properties cannot be applied. For this reason, the above processing method is not a good method.

In response to the above-mentioned problems, methods for improvement have been submitted according to domestic and foreign patent gazettes and related materials. For example, US Pat. Nos. 5,306,349 and 6,066,229 are methods in which a pretreatment is performed with a chemical solvent and the substrate and the thin film are separated by ultrasonic vibration. In addition, US Patent No. 5619898 and Taiwan Patent Publication No. 464595, “Disposal Method of Optical Disc and Apparatus and Optical Disc” all use a mechanical external force to scrape the coated thin film material layer. The “Recycling Method of Recordable Optical Disc Piece (CD-R)” in Public Notice No. 443949 is a method of crushing an optical disc finely, separating various materials using a solvent, and using it for recycling. However, in the above-mentioned various methods, those using chemicals tend to be problematic due to contamination due to subsequent recycling and discharge of waste liquid, and the method using a machine tends to damage the substrate, There is a drawback that it cannot be reused as a base material for optical disks. Furthermore, the equipment associated with these methods is expensive, heavy and difficult to operate, making it inconvenient, time consuming and complex.
US Patent US5306349 US Patent US6066229 US Patent US5619898 Taiwan Patent Notice No.464595 Taiwan Patent Publication No. 443949

In addition, another method has been proposed in which a thin film material layer is removed using a chemical agent and the substrate material is recycled. Japanese Patent No. 2615277 and Japanese Patent Laid-Open No. 8-164524 are examples thereof. However, the processing methods described in these publications easily cause physical changes in the substrate material during the processing process, and it is difficult to ensure the expected quality of the recycled substrate. In particular, even if you want to recycle the entire substrate and reuse it as an optical disk substrate, you cannot achieve its purpose, but only reuse it as a process plastic with relatively low economic value. It is not possible to make use of its optical characteristics. In addition, the polycarbonate resin base material that has been treated with a chemical solution is easily affected, so it cannot be used for expensive optical applications, and its mechanical properties are also affected, making it worth reusing. It will decline. For this reason, treatment with a chemical solvent also has a problem that is difficult to solve.
Japanese Patent No. 2615277 JP-A-8-16524

  In view of the foregoing problems, the present invention can quickly and economically and effectively dissociate the optical recording medium substrate and its thin film material without causing contamination, and in the process of recycling the optical recording medium. An object of the present invention is to provide a method for dissociating an optical recording medium substrate and its thin film material that can be used.

  The present invention utilizes the characteristics of the selective action of electromagnetic waves, destroys the metal reflection layer of the optical recording medium by concentrating energy within a short time, and separates it from the other layers with the absorbed energy, thereby enabling optical recording. The substrate layer and the thin film layer of the medium can be recovered quickly and effectively, without causing contamination, maintaining its original physical properties, and used for high value reuse.

  According to the processing method of the present invention, since the substrate layer and the thin film layer of the optical recording medium can be separated with high efficiency with a simple operation and low cost, it is possible to recover a highly pure substrate material that is not deformed. Enables the subsequent recycling of substrates, efficiently removes unnecessary thin layers from waste optical recording media, and recovers and reuses substrate materials, greatly reducing optical disc costs The advantages of safe and reliable, low cost, high value reuse, etc. can be obtained.

  The contents and effects of the present invention will be described in detail below based on specific examples of the method for dissociating the optical recording medium substrate and the thin film material of the present invention.

  The present invention is a method for dissociating an optical recording medium substrate and its thin film material, and mainly dissociates the substrate and the thin film layer using electromagnetic waves. Among them, the electromagnetic wave implementation environment can be a microwave oven. For example, when the optical recording medium is placed in a microwave oven and dissociation is performed with variables such as a microwave frequency of 2450 MHz, an output of 100 W, and a time of 3 seconds, the reflective layer and the dye layer in the optical recording medium are peeled or cracked, and In the reflection layer, radial cracks are formed. In this way, the thin film layer is rapidly broken, and at the same time, the substrate and the thin film layer are rapidly and completely dissociated.

  The method described above utilizes the characteristics of the selective action of microwaves in the dissociation operation, and concentrates the energy to destroy the metal layer, the reflective layer, etc. (ie, the thin film material) of the optical recording medium within a short time. Then, it is quickly separated from other layers by the absorbed energy. According to this dissociation method, a large amount of dissociation can be performed reliably and in a short time, and a high effect can be obtained.

   In addition, when the optical recording medium described above enters the dissociation process, the optical recording medium capable of absorbing the engaging and absorbing microwaves is placed in a microwave environment, and the microwave output is adjusted to perform the dissociation. The process in which the waves are acting can be observed directly from the window of a microwave device (for example, a microwave oven).

   In addition, semi-finished products that have undergone microwave dissociation may be further thoroughly dissociated with mechanical force or ultrasound, or dissociated in advance with mechanical force or ultrasound and then dissociated with microwave. You may be thorough.

   Further, by removing the release layer by applying an air flow at the time of dissociation by the above-described microwave, it is possible to save separation time and energy.

Furthermore, there are the following methods for placing the optical recording medium in a microwave environment.
1. Lot type: The optical recording medium is divided into lots and put in and out of the microwave environment.
2. Semi-continuous type: The optical recording medium is sent to the microwave environment by the transport belt, stops traveling, and is dissociated by the microwave.
3. Continuous type: The optical recording medium is sent to the microwave environment by the transport belt, dissociation by the microwave is performed while continuing the progress, and after the dissociation is completed, the optical recording medium leaves the microwave environment.
All of the aforementioned methods can achieve the purpose of dissociation and can be employed in the present invention.

  If the frequency of the electromagnetic wave is within the microwave range, the reflective layer can be destroyed and dissociated by other methods, and the same effect can be obtained.

  Furthermore, the action of the electromagnetic wave on the reflective layer also acts on the dye layer, dielectric layer or optical recording layer, and phenomena such as dissolution, evaporation, phase change occur, and can be destroyed and dissociated. It shall belong to the range.

  Optical recording media that can be destroyed and dissociated by microwaves as described above are read-only music CDs, CD-ROMs, Video-CDs, CD-Is, DVD-Videos, DVD-ROMs, and write-once CD-ROMs. Includes R, WORM, DVD-RAM, rewritable CD-RW (rewritable optical disc), MO (magneto-optical disc machine), MD (mini optical disc), DVD-RW, etc. These optical recording media are all reflective lasers Since a metal reflective layer required by light is provided, and this metal layer is easily destroyed and dissociated by the action of microwaves in a microwave environment, the present invention is applied to all optical recording media having metal layers. Can be applied.

  In the examples, an optical disc provided with a recording layer, a reflective layer, and a protective layer on a substrate layer is an object to be processed. However, a damaged product that occurred during the production of an optical recording medium, and a defective product in a final inspection after the production. It is possible to cover all items such as goods or surplus items after being made good. That is, no matter what layer is formed on the substrate layer, if the metal layer is provided, the same processing method as described above can be used, and the substrate material and the thin film material can be surely dissociated. Is possible.

Further, when the method of the present invention is used in the “recovery (or reproduction) process of an optical recording medium”, it can be performed by the following procedure.
a. Classification: 光 Classify each optical recording medium according to recycled materials. For example, there are classifications based on differences in the materials contained in the reflective layer (eg, gold, silver, aluminum), classifications based on differences in substrate materials, and the like.
b. Dissociation by electromagnetic waves: The substrate and the thin film layer are dissociated using electromagnetic waves. At the same time as the thin film layer is rapidly destroyed, the substrate and the thin film layer are also quickly and completely dissociated.
c. Recovery and reuse: The separated substrate material and thin film material are recovered and reused depending on the material.

  In the above-mentioned application example “recovery (or reproduction) process of optical recording medium”, the dissociation method provided by the present invention makes the entire recycling process of the individual optical recording medium faster and has an economic effect, Furthermore, it is possible to maintain a high-value reusability in the collected material and to effectively suppress the problem of secondary contamination in the recycling process.

  The processing method according to the present invention is applied to an optical recording medium which is damaged in the manufacturing process, an optical recording medium which has been determined to be defective in the final inspection process after manufacturing, or an optical recording medium which has become an excess inventory product. The substrate material can be collected and recycled for use. Since the highly purified substrate material can be recovered, the recovered substrate material can be reused as a substrate for optical recording media, and can be used for a wide range of applications such as optical disk packaging cases and personal computer housings. In addition, since the optical disk material can be easily recycled, a very high economic effect can be obtained, and the problem of secondary contamination in the recovery process in the optical recording medium can be effectively avoided.

Claims (5)

  A method of dissociating an optical recording medium substrate and its thin film material, mainly by placing an engaging optical recording medium in an electromagnetic wave environment and destroying the thin film material layer of the optical recording medium by using electromagnetic wave concentration energy. A method of dissociating an optical recording medium substrate and its thin film material by absorbing energy and quickly separating it from other layers to separate the substrate material and the thin film material.   Semi-finished products that have undergone dissociation by electromagnetic waves are more thoroughly dissociated by direct mechanical force or ultrasonic waves, or after being dissociated by mechanical force or ultrasonic waves in advance, they are more thoroughly dissociated by electromagnetic waves. The method of dissociating the optical recording medium substrate according to claim 1 and its thin film material.   The method for dissociating an optical recording medium substrate and its thin film material according to claim 1, wherein when the dissociation is performed by electromagnetic waves, an air stream is simultaneously applied to remove the release layer.   The method of dissociating an optical recording medium substrate and its thin film material according to claim 1, wherein the method of installing the optical recording medium in an electromagnetic wave environment is one of a lot type, a semi-continuous type, and a continuous type.   The method for dissociating an optical recording medium substrate and its thin film material according to claim 1, wherein the electromagnetic wave frequency is not lower than the range of the microwave frequency.