JP2006088111A - Transparent layer production method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a production method for forming a transparent hard coat layer by a tension control mechanism forming no wrinkle even using a polycarbonate base. <P>SOLUTION: In the production method for forming the transparent hard coat layer on the base using a transparent layer production apparatus for an optical information recording medium provided with a tension adjustment mechanism with a tension roller on the way to the polycarbonate base is conveyed and wound and lapping the polycarbonate base on the tension roller, a range that the polycarbonate base is brought into contact with the tension roller is made to 120° or less at a central angle of the tension roller. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to the production of a transparent layer for an optical information recording medium, and specifically relates to tension control of a base film used for the transparent layer of an optical information recording medium.

  Currently, in order to support the recording of digital high-vision TV broadcasts, research on optical information recording media that enable higher-density recording than high-density optical information recording media (DVD) is underway. And optical disk systems using high NA (Numerical Aperture) pickups have been developed.

  As such an optical disk system, for example, there is a next-generation optical disk standard called a blue-ray disk. A blue ray disc is an optical information recording medium having a recording layer on a substrate and a transparent layer on the laser incident side of the recording layer. For example, as shown in Japanese Patent Application Laid-Open No. 2000-67468, the transparent layer is formed by applying a hard coat layer for preventing scratches to the surface of a light transmission layer made of polycarbonate.

  As a method for forming the transparent layer, for example, an ultraviolet curable material for forming a hard coat layer on a base by an application member while a polycarbonate base used as a base film of the transparent layer is conveyed by a driving roller. There is a method in which a composition is applied, dried, and then cured by ultraviolet irradiation.

FIG. 3 is an overall configuration diagram illustrating a conventional example of a transparent layer manufacturing apparatus targeted by the present invention.
In the figure, 10 is an apparatus for producing a transparent layer for an optical information recording medium, 1 is a base fabric, 2 is a pass roller, 3 is a coating unit, 3a is a coating member, 3b is a coating rod, 4 is a pass roller, 5 is a pull roller, Reference numeral 6 denotes a drying unit, 7 denotes an ultraviolet irradiation unit, 8 denotes a winding roll, and 20 ′ denotes a tension control mechanism that controls the tension of the base at the time of winding the base to be constant.
As shown in the figure, a transparent layer manufacturing apparatus 10 is provided between a base material (bulk) 1 formed by winding a base B made of polycarbonate, and a winding roll 8 that winds and holds the base B. Thus, the base B is conveyed by being sent out from the base material 1 to the take-up roll 8. The thickness of the base B is 80 μm to 100 μm.

  The application unit 3 is provided with an application member 3a connected to an application liquid supply unit (not shown). The coating member 3a attaches the coating liquid D supplied from the coating liquid supply unit to the coating rod 3b that functions as a coating nozzle, rotates the coating rod 3b, and presses the coating rod 3b against the surface of the base B. In this configuration, the coating liquid D is applied.

The application member 3a is a movable member that can be arbitrarily set between a position where the application rod 3b is pressed against the base B (a position where the application rod 3b is wrapped) and a position where the application rod 3b is separated from the base B (a standby position). It is configured.
As the coating member 3a, a bar coater type can be used. At the time of coating, the coating member 3a is lifted from the standby position, and the bar-shaped coating rod (coating nozzle) 3b is transported upward to the base B. The coating liquid D is coated on the surface of the base B by pressing (wrapping) and rotating the coating rod 3b.
Other than during application, the application member 3a is retracted, and the application nozzle 3b is separated from the base B.

  In the conveying direction of the base B, pass rollers (drive rollers) 2 and 4 are provided on the upstream side and the downstream side of the coating nozzle 3b. These drive rollers 2 and 4 are driven by the drive unit 9 so as to rotate at a constant speed in the direction of sending out the base B in the transport direction during application.

  As an example of the coating liquid D, a composition comprising a solvent such as isopropyl alcohol (IPA), methyl ethyl ketone (MEK), methyl ethyl butyl ketone (MIBK), Si particles, an ultraviolet curable resin, and a polymerization initiator. Is used.

  The pull roller 5 is a roller which is rotationally driven at the time of application and serves as a reference for the transport speed of the base B when the base B is transported in contact with the base B on its peripheral surface. The pull roller 5 is controlled by a pull roller control unit (not shown) and transports the base B at a constant speed. The pull roller 5 may have a configuration in which a groove is provided on the surface in order to secure a holding force with respect to the base B, or a configuration in which the base B is sucked and held by sucking air.

  The drying unit 6 is configured to dry the coating liquid D applied to the base B while transporting the base B.

  The ultraviolet irradiation unit 7 is configured to irradiate the surface of the base B on which the coating liquid D is applied with the ultraviolet light, and to cure the coating layer. Here, as long as the coating liquid D can be cured, the ultraviolet irradiation unit 7 may be configured to irradiate light having an active energy other than ultraviolet rays.

Next, the function of the tension control mechanism will be described.
The tension control mechanism itself is known (see, for example, Patent Document 1).

JP 2001-328756 A JP 2003-54800 A

  The technical idea commonly seen in Patent Documents 1 and 2 relates to control of the web feeding of the line, and a dancer roller is arranged between the feeding section and the winding section to carry the web. Then, the dancer roller swings up and down due to the change in the conveying speed, and the displacement of the dancer roller is detected by the displacement detecting means and outputted to the dancer control circuit. In the dancer control circuit, the displacement amount is converted into a speed correction value, and the peripheral speeds of the feed roll and the take-up roll by the drive motor are corrected via the speed control circuit.

FIG. 4 shows an example in which a known tension control mechanism 20 ′ is employed in this apparatus, and 20 ′ is a tension adjustment mechanism. The tension adjusting mechanism 20 ′ is composed of a tension roller 21 that can move up and down, an upstream guide roller (fixed) 22, and a downstream guide roller (fixed) 23. The tension roller 21 can be pivoted to a machine base fixing portion 26. It is provided at the tip of the fixed tension arm 24. A tension spring 25 is engaged with an intermediate portion of the tension arm 24, and the other end of the tension spring 25 is fixed to the machine base fixing portion 27.
An arm movement amount sensor 28 is connected to the tension arm 24, and a detected value of the magnitude and direction proportional to the movement amount of the tension arm 24 is sent to a pull roller control device (not shown) or a motor speed control circuit (not shown). send.

  In the pull roller control device, the tension control to the base B is performed by vertically moving the pull pull for control of the transport system in the transport system in accordance with the magnitude and direction of the received movement amount.

  The motor speed control circuit performs tension control on the base B by correcting the peripheral speeds of the feed roll and the take-up roll by the drive motor according to the magnitude and direction of the received movement amount.

  Returning to FIG. 4, the load of the tension roller 21 and the tension of the tension spring 25 act downward on the tension arm 24, while the tension on the base B acts upward, and each has the same size. By the way, it is balanced, and the tension arm 24 remains stationary.

  When a large tension is applied to the base B, the tension arm 24 is moved upward by this tension, the movement amount of the tension arm 24 is detected by the arm movement amount sensor 28, and the output of the arm movement amount sensor 28 is (1). It is sent to a pull roller control device (not shown), and the tension on the base B is lowered by moving the pull roller up and down to lower the tension roller 21 to the original position, or (2) described in the cited document 1 As described above, the output of the arm movement amount sensor is sent to a motor speed control circuit (not shown), the peripheral speed of the feed roll and the take-up roll by the drive motor is corrected, the tension on the base B is lowered, and the tension roller 21 Is lowered to the original position.

  On the contrary, if the tension applied to the base B is weaker than a predetermined value, the tension arm 24 is moved downward by the tension spring 25. Similarly, the arm movement amount sensor 28 detects the movement amount of the tension arm 24, and the arm The output of the movement amount sensor 28 is sent to (1) the pull roller control device or (2) the motor speed control circuit, and the pull roller or motor is controlled to increase the tension to the base B, and the tension roller 21 is returned to the original position. I try to raise it.

  However, the present applicant has noticed that wrinkles sometimes occur in the base B manufactured as described above. In pursuit of the cause, wrinkles did not occur when base B was PET (polyethylene terephthalate) or PEN (polyethylene naphthalate), whereas wrinkles occurred when base B was polycarbonate. As a result, it was found that polycarbonate is prone to wrinkles at large lap angles because of its high smoothness (hardness to slip).

  Accordingly, an object of the present invention is to provide a manufacturing method for forming a transparent hard coat layer by a tension control mechanism that is not wrinkled even when a polycarbonate base is used. .

  In order to solve the above-mentioned problem, the invention according to claim 1 relates to a method for producing a transparent layer, wherein a pass roller is interposed in the course of transporting a polycarbonate base from a polycarbonate base roll and winding it on a take-up roll. In the manufacturing method for forming a transparent hard coat layer on the base using a transparent layer manufacturing apparatus for an optical information recording medium formed by wrapping a polycarbonate base, a range in which the polycarbonate base is brought into contact with the pass roller is determined. The central angle (hereinafter referred to as “lap angle”) is 120 degrees or less.

  The invention according to claim 2 relates to a method for producing a transparent layer, comprising a tension adjusting mechanism with a tension roller in the middle of transporting the polycarbonate base from the polycarbonate base roll to winding it on the take-up roll. In a manufacturing method for forming a transparent hard coat layer on the base using a transparent layer manufacturing apparatus for an optical information recording medium formed by wrapping a polycarbonate base, a range in which the polycarbonate base is brought into contact with the tension roller is a wrap angle. It is characterized by being 120 degrees or less.

  According to a third aspect of the present invention, in the transparent layer manufacturing method according to the second aspect, the tension roller has a diameter of 150 mm or less.

  Bases with high smoothness, such as polycarbonate, tend to wrinkle at large wrap angles, and on the contrary, they slip between the rollers even if the wrap angle with the pass roller or tension roller is not so large because of the large smoothness. Focusing on the fact that no crease occurs, by setting the wrap angle to 120 degrees or less as in the above configuration, it is difficult to wrinkle and the bite between the tension roller is sufficient and slip does not occur. .

Hereinafter, the best mode for carrying out the present invention will be described.
FIG. 1 is an overall configuration diagram illustrating a transparent layer manufacturing apparatus according to the present invention.
In the figure, 10 is an apparatus for producing a transparent layer for an optical information recording medium, 1 is a base material made of polycarbonate, 2 is a pass roller, 3 is a coating portion, 3a is a coating member, 3b is a coating rod, 4 is a pass roller, 5 Is a pull roller, 6 is a drying section, 7 is an ultraviolet irradiation section, 8 is a winding roll, and 20 is a tension control mechanism for controlling the tension of the base at the time of winding the base according to the present invention.
As shown in the drawing, the parts other than the tension control mechanism 20 that match the reference numerals in FIG. 3 are the same as those in FIG.

Next, the function of the tension control mechanism according to the present invention will be described with reference to FIG. 2A and 2B are perspective views of the tension control mechanism according to the present invention, in which FIG. 2A is an example of a wrap angle θ1 = 120 degrees, FIG. 2B is an example of a wrap angle θ2 = 90 degrees, and FIG. 2A to 2C, reference numeral 20 denotes a tension adjusting mechanism according to the present invention. The tension adjusting mechanism 20 includes a tension roller 21 that can move up and down, an upstream guide roller (fixed) 22, and a downstream guide. The tension roller 21 is provided at the tip of a tension arm 24 that is pivotally fixed to a machine base fixing portion 26. A tension spring 25 is engaged with an intermediate portion of the tension arm 24, and the other end of the tension spring 25 is fixed to the machine base fixing portion 27.

In the tension control mechanism (a), the positional relationship among the tension roller 21, the upstream guide roller 22 and the downstream guide roller 23 is such that the range in which the polycarbonate base B is brought into contact with the tension roller 21 is the central angle (wrapping) of the tension roller 21. (Angle) It is arranged to be 120 degrees at θ1.

In the tension control mechanism (b), the positional relationship between the tension roller 21, the upstream guide roller 22, and the downstream guide roller 23 is such that the range in which the polycarbonate base B is brought into contact with the tension roller 21 is the center angle (wrapping) of the tension roller 21. (Angle) It is arranged to be 90 degrees at θ2.

In the tension control mechanism (c), the positional relationship among the tension roller 21, the upstream guide roller 22 and the downstream guide roller 23 is such that the range in which the polycarbonate base B is brought into contact with the tension roller 21 is the central angle (wrapping) of the tension roller 21. The angle is set so that θ3 is 60 degrees.

On each tension arm 24, the load of the tension roller 21 and the tension of the tension spring 25 act downward, while the tension 1 to the base B acts upward and balance each other at the same size. The tension arm 24 remains stationary.
When a large tension is applied to the base B, the tension arm 24 is moved upward by this tension and an excessive tension applied to the base B is absorbed. As a result of the tension arm 24 moving upward, the tension spring 25 extends to increase the pulling force, and the tension arm 24 stops when balanced.
On the other hand, when the tension applied to the base B is weaker than a predetermined value, the tension arm 24 is moved downward by the tension spring 25 so that the predetermined tension is applied to the base B, and the tension arm 24 stops when balanced. .
Thus, the tension control mechanism 20 is adjusted so that a predetermined tension is always applied to the base B.

<Examples and comparative examples>
Next, with respect to the present invention, an experiment was conducted on an example and a comparative example as to how the lap angle θ changes when the roller diameter is fixed to 150 mm.
The results are shown in Table 1.

In Comparative Example 1, wrinkles were generated when the roller diameter = 150 mm and the wrap angle θ = 180 degrees.
When the wrap angle θ of Comparative Example 2 was set to 150 °, wrinkles were slightly generated.
When the wrap angle θ was 120 degrees in Example 1, no wrinkle was generated.
When the wrap angle θ was 90 degrees in Example 2, wrinkles were not generated.
In Example 3, when the wrap angle θ = 60 degrees, wrinkles were not generated.
When the wrap angle θ = 50 degrees in Comparative Example 3, wrinkles did not occur, but some slip occurred.
In Comparative Example 4, when the wrap angle θ was 45 degrees, no wrinkles occurred, but slipping occurred.

Next, with respect to the present invention, when the wrap angle θ = 120 degrees was constant, an experiment was conducted on an example and a comparative example as to how the roller diameter would change.
The results are shown in Table 2.

When the roller diameter of Comparative Example 1 was 180 mm, many wrinkles occurred.
Wrinkles were generated even when the roller diameter of Comparative Example 2 was 160 mm.
When the roller diameter was set to 150 mm in Example 1, no wrinkle was generated.
In Example 2, when the roller diameter was 130 mm, wrinkles were not generated.
When the roller diameter was 120 mm in Example 3, wrinkles were not generated.
When the roller diameter was set to 100 mm in Comparative Example 3, wrinkles did not occur, but this time some slipping occurred.
In Comparative Example 4, when the roller diameter was 90 mm, no wrinkle was generated, but slipping occurred.

Next, with respect to the present invention, when the wrap angle θ = 60 degrees was constant, an experiment was conducted on an example and a comparative example as to how the roller diameter changed.
The results are shown in Table 3.

When the roller diameter of Comparative Example 1 was 180 mm, wrinkles were generated.
Even with the roller diameter of Comparative Example 2 = 160 mm, some wrinkles were generated.
When the roller diameter was set to 150 mm in Example 1, no wrinkle was generated.
In Example 2, when the roller diameter was 130 mm, wrinkles were not generated.
When the roller diameter was 120 mm in Example 3, wrinkles were not generated.
When the roller diameter was set to 100 mm in Comparative Example 3, wrinkles did not occur, but slipping occurred this time.
In Comparative Example 4, when the roller diameter was 90 mm, the slip frequently occurred.

  From the above, wrinkles are likely to occur when the diameter of the tension roller is increased, so it is necessary to select a small wrap angle θ. Conversely, as the diameter of the tension roller decreases, wrinkles are less likely to occur, but slippery. Therefore, it can be seen that it is necessary to select a large wrap angle θ. When the wrap angle θ defined in the present invention is 60 ° to 120 ° and the tension roller has a diameter of 150 mm or less, no wrinkle was generated on the base and no slip occurred.

As described above, according to the present invention, the range in which the polycarbonate base is brought into contact with the tension roller of the tension adjusting mechanism with the tension roller is set to 120 degrees or less in the wrap angle, thereby preventing the base from being wrinkled.
Further, by setting such a wrap angle, the base was not wrinkled even when the tension roller 21 had a diameter of 150 mm or less.

  The description of the present invention has been made with respect to an example of the tension roller of the tension control mechanism. However, the present invention is not limited to the embodiment shown here, and appropriate modifications and improvements can be made. For example, it goes without saying that the effect of the present invention is exhibited even when applied to a pass roller which is a roller other than a tension roller.

It is a whole block diagram explaining the transparent layer manufacturing apparatus which concerns on this invention. It is a perspective view of a tension control mechanism concerning the present invention, (a) is a lap angle of 120 degrees, (b) is a wrap angle of 90 degrees, and (c) is an example of a wrap angle of 60 degrees. It is a whole block diagram explaining the conventional transparent layer manufacturing apparatus. It is a perspective view of a conventionally well-known tension control mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base raw material 2, 4 Pass roller 3 Application | coating part 3a Application | coating member 3b Application | coating rod 5 Pull roller 6 Drying part 7 Ultraviolet irradiation part 8 Winding roll 9 Drive part 10 Manufacturing apparatus 20 of optical-information recording medium transparent layer 20 Tension control mechanism 21 Tension roller 22 Upstream guide roller 23 Downstream guide roller 24 Tension arm 25 Tension springs 26, 27 Machine base fixing part 28 Arm movement amount sensor

Claims (3)

Using a transparent layer manufacturing apparatus for an optical information recording medium, wherein a pass roller is interposed in the middle of conveying a polycarbonate base from a polycarbonate base roll and winding it on a take-up roll, and the polycarbonate base is wrapped on the pass roller. In the manufacturing method of forming a transparent hard coat layer on the base,
A method for producing a transparent layer, wherein a range in which the polycarbonate base is brought into contact with the pass roller is 120 degrees or less in terms of a center angle of the pass roller (hereinafter referred to as “wrap angle”). Production of a transparent layer for optical information recording media, comprising a tension adjusting mechanism with a tension roller in the middle of transporting the polycarbonate base from the polycarbonate base roll to winding it on the take-up roll, and wrapping the polycarbonate base on the tension roller In the manufacturing method of forming a transparent hard coat layer on the base using an apparatus,
A method for producing a transparent layer, characterized in that a range in which the polycarbonate base is brought into contact with the tension roller is 120 degrees or less in terms of a wrap angle. The method for producing a transparent layer according to claim 2, wherein the tension roller has a diameter of 150 mm or less.

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