RU2243599C1 - Method for compact disk manufacture - Google Patents

Abstract

FIELD: data carriers manufacturing technologies.

SUBSTANCE: method includes drying and melting down of source polymer, pressing melt in fixed disk-shaped press-form, containing matrix with information, hardening of melt during cooling, extraction of disk from press-form, applying of reflective layer, covering of reflective layer by protective film by centrifuging in the air, ultraviolet drying of film, applying of sticker. Disk is cooled in press-form. Transporting of source polymer is performed at temperature 90°C-120°C and till value of allowed remaining moisture level for polymer in weight percents no more than 0.02 during applying of reflective layer and cooling of disk, temperature of coolant fed to press-form and applying device is preserved within range from +4°C to +24°C. applying of sticker is performed by paints hardened by ultraviolet.

EFFECT: higher reliability, higher effectiveness.

8 cl, 1 dwg

Description

The invention relates to instrumentation, to optical storage devices, to methods for manufacturing storage media, and in particular to the technique of manufacturing a compact disc, and can be used for the manufacture of compact discs with a constant waveform.

The invention also relates to mass production of compact discs. The term “storage media” means both storage media of audio and / or video information and / or storage media and other storage media, such as CDs, and storage media made specifically for recording and storing sound, image and other information.

One of the most famous optical storage media of this kind is a compact disk, the main properties of which are established by the 1EC 908 standard and the Compact Disc Digital Audio System Description specification, June 1989, by Sony and Philips publishers. The CD has, among other things, the following features: information is recorded sequentially in the form of a spiral track and is read by reflection using a focused laser beam, in the plane of a smooth base surface, the focus diameter is equal to the track width of about 1 μm, tray-shaped ones follow each other within the track recesses, the so-called pits, separated from each other in the direction of the track and in the radial direction by sections of a smooth base surface.

A known method of manufacturing an optical information medium, including polymer melting, programmable injection under melt pressure into a fixed disk-shaped form with precision control of injection pressure and speed, melt curing during cooling, mold casting (Japanese Patent No. 59-196032, class G 11 V 7/26, 1984).

A significant disadvantage of this method is the anisotropy of the characteristics of the substrate. So, when moving from the center to the periphery of the substrate, its breaking strength decreases by 30%, birefringence increases by 70-100%. Such a spread of birefringence leads to an increase in the number of errors in reading information, which reduces the reliability of its storage.

A known method of manufacturing an optical information medium, including the operation of filling a fixed disk-shaped form with liquid organic material containing a matrix with information (marking, information relief), curing the material, removing the substrate from the form (Japanese Patent No. 61-74150, class G 11 B 7 / 23, 1986). A significant disadvantage of this method is the low reliability of information storage due to the reduced formability of the carrier casting as a result of shrinkage of the curable organic material, which leads to a deviation of the substrate parameters from the set values. This leads to distortion and loss of information. For example, in an optical medium of video information and stereo sound (video disc) it causes a signal to drop out, a decrease in the carrier-to-noise ratio, the appearance of defects such as “moire”, “failure of synchronization” during playback; in optical discs of single and reverse recording, it causes a decrease in the depth of the guide grooves, the roughness and thickness of the substrate, which leads to defects in the recording layer (thickness, discontinuity).

A known method of manufacturing a compact disc, including the operation of drying, melting, filling under pressure with a liquid polymer a fixed disk-shaped mold containing a matrix with information (marking, information relief), curing the material, removing the substrate from the mold, (see application DE 3428599, G 11 B 7/26, publ. 06.02.86). A significant disadvantage of the prototype is the high cost and low production efficiency due to the increased production time of a unit of production, low quality stability, low reliability and durability of the means of production, low reliability of information storage due to the reduced formability of the carrier casting as a result of shrinkage of the cured organic material, which leads to deviation of the substrate parameters from the set values.

The closest in technical essence and the achieved effect to the proposed solution is a method of manufacturing a compact disc, including drying and melting the original polymer, pressing the melt in a stationary disk-shaped mold containing a matrix with information, solidifying the melt during cooling, removing the casting of the compact disc from molds, spraying the reflective layer, coating the reflective layer with a protective varnish by centrifugation in air, ultraviolet drying of the varnish, applying a label, and casting azhdayut in the mold (see. RF patent №2163034 publ. 10.02.2001).

The disadvantage of this method is not sufficiently high quality stability and reliability.

The objective of the proposed technical solution is to stabilize the production process, reduce the production time, i.e. an increase in the number of compact discs produced per unit time, which means a reduction in the cost of manufacturing a serial compact disc due to the precision and rapid cooling of the casting, elimination of size dispersion, increased production efficiency, stabilized quality of products, increased reliability and durability of the tool due to its use as refrigerant with constant characteristics and with specified parameters. Reduced production cost of serial CDs. Improving the ecology of production by reducing harmful factors (fumes, ozone) in the production environment.

To solve the problem in a method of manufacturing a compact disc, including drying and melting the original polymer, pressing the melt in a stationary disk-shaped mold containing a matrix with information, solidifying the melt during cooling, removing the cast of the compact disc from the mold, spraying the reflective layer , coating the reflective layer with a protective varnish by centrifugation in air, ultraviolet drying of the varnish, applying a label, the casting being cooled in a mold, and transporting the starting polymer both bake by vacuum pipe line, the source polymer is dried to a press machine at a temperature of 90-120 ° C and to a value of the allowable residual moisture of the polymer in weight percent of not more than 0.02, and when spraying the reflective layer and when cooling the casting, the temperature of the refrigerant supplied to the mold and the spraying device, support in the range from 4 to 24 ° C, and the application of the label is produced with UV curable inks. Polycarbonate can be used as the starting polymer. As the initial polymer, color polycarbonate can be used, which is optically transparent in the wavelength region of the recording and reading laser radiation.

Pressing can be carried out with precision control of pressure, melt temperature, injection speed, holding under pressure, mold temperature and product cooling time, which are determined based on the physicochemical properties of the polymer used.

The reflection layer can be sprayed in an inert gas, such as argon.

As the material of the reflective layer, a metal layer, for example aluminum, or gold, or metal alloys can be used.

The cooling circuit can be made integral and connected to the mold.

As the refrigerant supplied to the mold and the spraying device, liquid, for example antifreeze, can be used.

As the refrigerant supplied to the mold and the spraying device, deionized (desalted) water can be used, and the resistance of deionized water at the entrance to the mold can be set within 0.1 MOM-15 MOM.

The method includes drying and melting the initial polymer (polycarbonate), pressing the melt in a stationary disk-shaped mold containing a matrix with information for precision pressure control, solidifying the melt during cooling, removing the cast from the mold, cathodic deposition of a reflective metal layer in an inert gas (argon) ), coating the reflective layer with a protective layer (varnish), ultraviolet drying (photo-curing) varnish (tanning), control, labeling with UV curable paints, and drying the source polymer is produced to the press machine at a temperature of 90-120 ° C and to the value of the allowable residual moisture of the polymer in weight percent - 0.02, the transportation of the source polymer is ensured by evacuation of the pipe line, when cooled, a liquid, such as deionized water or antifreeze, a protective layer is applied by centrifugation in air. The resistance of deionized water at the inlet to the press can be set within 0.1-15 MOM.

A method of manufacturing compact discs is presented in the form of a structural diagram shown in the drawing, where 1 is a vacuum pump, 2 is a drying unit, 3 is the melting and pressing of the original polymer in a mold, 4 is the deposition of a reflective layer on the surface of the base of the compact disc, 5 - coating the reflective layer with a protective varnish; 6 - ultraviolet drying of the photocurable varnish; 7 - control; 8 - labeling, 9 - inert gas (argon) supply unit, 10 - refrigerator, 11 - deionized water production unit. The cooling process is carried out by supplying a cooling liquid, for example deionized water or antifreeze to the mold and into the device for applying a reflective layer. As a coolant, deionized water of grade B (OST 11.02.9.003-90) or antifreeze is used.

The invention is illustrated by an example.

Example.

Water shirts are made in the mold body, into which liquid (desalted water) is supplied and discharged through appropriate fittings, creating a given temperature regime. A disk-shaped mold with a working cavity with a diameter of up to 130 mm, with a central hole with a diameter of 15 mm and a thickness of 1.2 mm is filled under pressure with a liquid polymer composition. The disk-shaped form contains a nickel matrix with service information (markup). Service information (marking) is intended for tracking (orienting) the laser beam when recording the information array on an optical information carrier. Filling is carried out in clean conditions of a purity class of 100-10,000 according to OST 1114.3302-87.

The polymer composition is cured. When the polymer composition is cured, the disk-shaped form is cooled. A liquid is used as a refrigerant, for example, deionized water with the following parameters - the inlet temperature in the mold is 13 ° C, the resistance is 0.1-15 MΩ. The time to reduce the temperature of the casting from 300 to 40 ° C is 3.5-5.1 s (in the prototype - 4.2 s).

The cured casting is removed from the disk-shaped form and transferred to the device for applying the reflective layer in compliance with the requirements of purity class 100 according to OST 1114, 3302-87.

Process environment parameters: purity class 100-10000 according to OST 1114, 3302-87, air temperature from 16 to 27 ° C, air humidity from 30 to 70%.

Analysis of the considered example shows that the proposed method allows significantly, in comparison with the prototype, to accelerate production. The proposed method is highly efficient by reducing the time required for cooling the base of the CD.

Claims (8)

1. A method of manufacturing a compact disc, including drying and melting the original polymer, pressing the melt in a stationary disk-shaped mold containing an information matrix, solidifying the melt during cooling, removing the cast of the compact disc from the mold, spraying a reflective layer, coating a reflective layers of protective varnish by centrifugation in air, ultraviolet drying of varnish, applying a label, and the casting is cooled in a mold, transportation of the original polymer is ensured by the vacuum method slab line, characterized in that the drying of the initial polymer is carried out at a temperature of 90-120 ° C and to a value of the allowable residual moisture content of the polymer in weight percent of not more than 0.02, and when spraying the reflective layer and cooling the casting, the temperature of the refrigerant supplied to the press form and spraying device, support in the range from 4 to 24 ° C, and labeling is done with UV curable inks. 2. The method according to claim 1, characterized in that polycarbonate is used as the starting polymer. 3. The method according to claim 1, characterized in that as the starting polymer using colored polycarbonate, optically transparent in the wavelength region of the recording and reading laser radiation. 4. The method according to claim 1, characterized in that the pressing is carried out with precision control of pressure, melt temperature, injection speed, holding under pressure, mold temperature and product cooling time, which are determined based on the physicochemical properties of the polymer used. 5. The method according to claim 1, characterized in that the deposition of the reflective layer is carried out in an inert gas, such as argon. 6. The method according to claim 1, characterized in that the metal layer of, for example, aluminum, or gold, or metal alloys is used as the material of the reflective layer. 7. The method according to any one of claims 1 to 6, characterized in that a liquid, for example antifreeze, is used as the refrigerant supplied to the mold and the spraying device. 8. The method according to any one of claims 1 to 6, characterized in that deionized water is used as the refrigerant supplied to the mold and the spraying device, and the resistance of deionized water at the entrance to the mold is set within 0.1- 15 MOhm.