JP4962848B2 - Deposition film thickness control method for web-like deposition material - Google Patents

Description

  The present invention provides a uniform vapor deposition film thickness in the length direction of a web-like vapor-deposited material by a continuous vacuum vapor deposition apparatus for vacuum-depositing a vapor deposition material on a continuous web-like vapor-deposited material such as plastic film, paper and cloth. It is related with the method of controlling.

  As shown in FIG. 1, a vacuum deposition apparatus for depositing a continuous web-shaped vapor deposition material is used to convey the unwinding device 2 for unwinding the continuous web-shaped vapor deposition material 14 and the web-shaped vapor deposition material 14. Transport roll 5, winding device 3 for winding the web-shaped vapor deposition material 14, crucible 6 for storing vapor deposition material 7 such as aluminum, zinc, copper and aluminum oxide, and heating the crucible 6 A heating device 8 for performing the operation, a shutter 9 for starting / stopping vapor deposition on the web-shaped vapor deposition material 14, a vapor deposition film thickness detector 12, a vacuum chamber 1, a vacuum pump 15, and an electric motor 10 for driving a transport roll. The speed detector 11 for the web-like vapor-deposited material 14, the vapor deposition film thickness control device 13, and the like.

In the vacuum vapor deposition apparatus having such a configuration, as a method of keeping the vapor deposition film thickness constant, conventionally, the vapor deposition film thickness is proportional to the temperature of the vapor deposition material and the web-like vapor deposition material is inversely proportional to the speed. Then, the method of controlling the evaporation amount of the vapor deposition material from the crucible by detecting the vapor deposition film thickness with a vapor deposition film thickness detector and changing the temperature of the vapor deposition material by changing the electric power supplied to the heating device 1) Or a method of changing the speed of the web-like deposition material by changing the speed of the electric motor while keeping the electric power supplied to the heating device constant (conventional method 2), and the conventional method 1 and the conventional method 2 A combined method (conventional method 3) has been adopted (see Patent Document 1).
JP-A-5-287528

  However, in the above-mentioned conventional method 1, since the heat capacities of the crucible and the vapor deposition material are large, even if the power P input to the heating device is changed, the temperature of the vapor deposition material in the crucible changes and stabilizes for several minutes. Therefore, it is difficult to keep the vapor deposition film thickness uniform while accelerating from the vapor deposition start speed Vs to the vapor deposition steady speed Vt and until stopping from the steady speed. Further, in the above conventional method 2, since the response speed of the electric motor is fast, it is effective for a sudden change in the deposited film thickness near the steady speed, but the power input to the heating device is constant. It has been difficult to keep the deposition film thickness uniform while accelerating from the deposition start speed Vs to the deposition steady speed Vt and until stopping from the steady speed. Further, even in the above-described conventional method 3 in which the conventional method 1 and the conventional method 2 are combined, it is difficult to keep the vapor deposition film thickness uniform during acceleration from the vapor deposition start speed Vs to the vapor deposition steady speed Vt. Losses occur at the start and end of the.

  The present invention is intended to solve the above problems, and by making the deposition film thickness uniform from the low speed at the start of deposition to the steady speed, loss can be reduced and productivity can be improved. Another object of the present invention is to provide a method for controlling the vapor deposition film thickness of a web-shaped vapor deposition material.

  The vapor deposition film thickness control method for a web-like vapor-deposited material according to the present invention that solves the above-mentioned problems is performed by using a heating means for heating and evaporating the vapor-deposited material on at least one surface of a continuous web-like vapor-deposited material under reduced pressure. In the vacuum vapor deposition apparatus, when controlling the vapor deposition film thickness based on the vapor deposition film thickness detection means for detecting the vapor deposition film thickness on the surface of the web-shaped vapor-deposited material and the detection value by the vapor deposition film thickness detection means, While the traveling speed of the material to be deposited is being accelerated from the start of deposition to the traveling speed at steady deposition, the amount of power introduced for heating and evaporating the deposition material is increased stepwise by a preset program. A vapor deposition film thickness control method for a web-shaped vapor deposition material, characterized in that a traveling speed of the web-shaped vapor deposition material is controlled from a deviation between a detection value of a film thickness detection means and a target film thickness.

  Further, in the method for controlling the deposition film thickness of the web-shaped vapor deposition material according to the present invention, after the traveling speed of the web-shaped vapor deposition material reaches the traveling speed at the time of steady deposition, the traveling speed of the web-shaped vapor deposition material. Controlling the amount of introduced power from the deviation between the detection value of the vapor deposition film thickness detection means and the target film thickness while maintaining the speed during steady vapor deposition is included as a preferred embodiment.

  According to the vapor deposition film thickness control method for a web-shaped vapor deposition material of the present invention, when the vapor deposition material is heated and vapor-deposited on a continuous web-shaped vapor deposition material, acceleration from a vapor deposition start speed to a steady vapor deposition speed is achieved. Since the vapor deposition film thickness can be kept uniform from the vapor deposition portion to the vapor deposition processing at the steady vapor deposition rate, the loss can be reduced and the productivity can be improved.

In the vacuum deposition apparatus for vapor deposition using a heating means for heating and evaporating the deposition material on at least one surface of the continuous web-like deposition material under reduced pressure, When controlling the vapor deposition film thickness based on the detection value by the vapor deposition film thickness detection means and the vapor deposition film thickness detection means for detecting the vapor deposition film thickness on the surface of the web-shaped vapor deposition material,
(A) During the acceleration from the start of vapor deposition to the traveling speed at the time of steady vapor deposition, the web-like vapor deposition material is stepped by a program in which the amount of introduced power for heating and evaporating the vapor deposition material is set in advance. While controlling the traveling speed of the web-shaped vapor deposition material from the deviation between the detection value of the vapor deposition film thickness detection means and the target film thickness,
(B) After the traveling speed of the web-shaped vapor deposition material reaches the traveling speed at the time of steady vapor deposition, the vapor deposition film thickness detection means detects the web-shaped vapor deposition material while maintaining the traveling speed of the web-shaped vapor deposition material at the speed at the time of steady vapor deposition. This is a method of controlling the amount of introduced power from the deviation between the value and the target film thickness.

Specifically, the traveling speed of the web-like deposition material is V, the running speed of the web-like deposition material at the start of deposition is Vs, the running speed of the web-like deposition material during steady deposition is Vt, and the deposition material is heated. When the amount of electric power introduced for evaporation is P,
(A) While the traveling speed V of the web-like vapor-deposited material is lower than the traveling speed Vt at the time of steady deposition with Vs ≦ V <Vt, the introduced power amount P is gradually increased by a preset program, Accelerate while controlling the traveling speed V of the web-like vapor deposition material from the deviation between the detection value of the vapor deposition film thickness detection means and the target film thickness
(B) After the traveling speed V of the web-shaped vapor deposition material reaches the traveling speed Vt at the time of steady vapor deposition with V = Vt, the speed V of the web-shaped vapor deposition material is maintained at the speed Vt at the time of steady vapor deposition, Control is performed by increasing or decreasing the introduced power amount P from the deviation between the detected value of the deposited film thickness detection means and the target film thickness.

  That is, the vapor deposition film thickness control according to the present invention is as follows: (a) Deposition is started, and the traveling speed V of the web-like deposition material is accelerated from the running speed Vs of the web-like deposition material at the start of deposition to the steady deposition speed Vt. And (b) after the traveling speed V of the web-like material to be deposited reaches the steady deposition speed Vt, it is divided into two stages of a constant deposition speed Vt.

  For example, the traveling speed Vs of the web-like material to be deposited at the start of deposition is usually 100 m / min or less, that is, about 0 m / min to 100 m / min, and the steady deposition speed Vt is usually about 200 m / min to 1000 m / min. is there. Further, the difference between the traveling speed Vs at the start of vapor deposition and the steady vapor deposition speed Vt is preferably at least 50 m / min, and is usually about 100 m / min to 800 m / min.

  In the present invention, the introduced power amount P is increased stepwise by a preset program. This is achieved by increasing the power by ΔP at certain time intervals Δt. When the amount of introduced power is increased stepwise, it can be raised stepwise in at least two steps. For example, the program can be set so that the voltage value of the heating power is raised stepwise from 10 V to 500 V in 5 V steps at 10 second intervals.

  Next, a method for controlling the deposited film thickness of the web-like material to be deposited according to the present invention will be described with reference to the drawings. First, FIG. 1 is a side sectional view for illustrating a vacuum deposition apparatus used in the present invention.

  In FIG. 1, a vacuum deposition apparatus for depositing a continuous web-shaped vapor deposition material 14 includes an unwinding device 2 for unwinding the continuous web-shaped vapor deposition material 14 in the vacuum chamber 1 and its web-shaped deposition material. The transport roll 5 for transporting the vapor deposition material 14, the cooling roll 4, the winding device 3 for winding the continuous web-shaped vapor deposition material 14, and the vapor deposition material 7 such as aluminum, zinc, copper and aluminum oxide are stored. A crucible (crucible) 6 for heating, a heating device 8 for heating the crucible (crucible) 6, a shutter 9 for starting / stopping vapor deposition on the web-shaped vapor deposition material 14, and a vapor deposition film thickness detection means The vapor deposition film thickness detector 12 is accommodated.

  The inside of the vacuum chamber 1 is controlled and held under reduced pressure by a vacuum pump 15, and the web-like vapor deposition material 14 released from the unwinding device 2 is wound around the winding device 3 through the transport roll 5 and the cooling roll 4. While being taken, the vapor deposition material 7 heated by the heating device 8 which is a heating means is vapor-deposited.

  In FIG. 1, a vapor deposition film thickness control device 13 connected to the vapor deposition film thickness detector 12 is disposed outside the vacuum chamber 1 and receives a film thickness detection value from the vapor deposition film thickness detector 12. The vapor deposition film thickness controller 13 is further connected to an electric motor 10 for driving the conveyance roll 5 and the cooling roll 4 via a speed detector 11. The vapor deposition film thickness control apparatus 13 uses the conveyance roll 5 and the cooling roll 4. , And the traveling speed of the web-shaped vapor deposition material 14 is controlled accordingly. The vapor deposition film thickness control device 13 is connected to the heating device 8 in the vacuum chamber 1, senses the film thickness detection value from the vapor deposition film thickness detector 12, controls the amount of introduced power, and heats Thus, the temperature in the vacuum chamber 1 is controlled.

  Specifically, the detected value of the deposited film thickness detected by the deposited film thickness detector 12 and the speed value detected by the speed detector 11 of the web-like deposition target material 14 are sent to the deposited film thickness control device 13. . The vapor deposition film thickness control device 13 performs arithmetic processing, which will be described later, to control the speed of the electric motor 10, that is, the traveling speed of the web-shaped vapor deposition material 14 and the amount of electric power supplied to the heating device 8.

  FIG. 2 and FIG. 3 show block diagrams of vapor deposition film thickness control according to the present invention. FIG. 2 is a control block diagram for explaining a control method during which the traveling speed V of the web-like deposition target material is lower than the traveling speed Vt during steady deposition. FIG. 3 is a control block diagram for explaining a control method after the traveling speed V of the web-like material to be deposited reaches the traveling speed Vt during steady deposition. As shown in FIGS. 2 and 3, the vapor deposition film thickness control device 13 has a transfer speed control function and a heating power control function.

  The vapor deposition film thickness control according to the present invention is as follows: (a) while vapor deposition is started and the traveling speed V of the web-shaped vapor deposition material is accelerated from the traveling speed Vs of the web-shaped vapor deposition material at the start of vapor deposition to the steady vapor deposition speed Vt. (B) After the speed V of the web-like material to be deposited has reached the steady deposition speed Vt, the process is performed in two stages of the constant deposition speed Vt.

  (A) First, during the period from the start of vapor deposition to acceleration of the web-like vapor deposition material speed V from the travel speed Vs of the web-like vapor deposition material at the time of vapor deposition to the steady deposition speed Vt, that is, the web-like vapor deposition material. When the speed V is lower than the steady speed speed Vt, the amount of power P introduced from the heating device is increased stepwise in accordance with a program preset in the heating power command calculator. The amount of evaporation of the vapor deposition material increases with an increase in the introduced power amount P of the heating device. The deviation Δt between the detection value of the film thickness detector and the preset target film thickness is calculated, the film thickness deviation Δt is sent to the speed change amount calculator, and the speed deviation ΔV proportional to the film thickness deviation Δt. Is sent to the speed command calculator. The speed command calculator sends a speed V = (V + ΔV) of a new web-shaped vapor deposition material obtained by adding the calculated speed deviation ΔV to the speed V of the web-shaped vapor deposition material to the motor, and the web-shaped vapor deposition material. The deposition film thickness is controlled by changing the speed V of the material. By repeating this step, the speed V of the web-like material to be vaporized increases as the amount of power P introduced by the heating device increases while the vapor deposition film thickness is controlled to be constant.

  (B) When it is determined that the traveling speed V of the web-shaped vapor deposition material detected by the speed detector by the speed deviation calculator has reached the steady vapor deposition speed Vt, the speed change command computing unit travels the web-shaped vapor deposition material. A command is issued to the electric motor to keep the speed V at the steady deposition speed Vt. The deviation Δt between the detected value of the film thickness detector and the preset target film thickness is calculated, the film thickness deviation Δt is sent to the heating power change amount side, and the heating power deviation Δ proportional to the film thickness deviation Δt is calculated. P is calculated and sent to the superheat power command calculator. The heating power command calculator sends a new power P = (P + ΔP) obtained by adding the calculated power deviation ΔP to the heating introduction power amount P to the heating device, and changes the heating power to change the deposition film thickness. Control. In this way, the deposition film thickness can be kept uniform from the deposition start rate to the steady deposition rate.

  As a heating means for heating and evaporating the vapor deposition material used in the present invention, a predetermined amount of the vapor deposition material is charged into a carbon crucible and heated by an electromagnetic induction method, a method of heating by flowing an electric current through a resistor, and an electron beam Although the method of directly irradiating and heating a vapor deposition material etc. is mentioned, the evaporation amount per unit time can be changed and controlled by changing the introduced power amount P in any method.

  As a means for detecting the deposited film thickness, there are a method using a light transmission (absorption) rate meter, a method using an eddy current meter, a method using a fluorescent X-ray measuring instrument, a method using a light interference order, etc. The optimum material can be selected and used according to the properties of the web-like material to be deposited and the properties of the deposition material.

  Examples of the vapor deposition material include metal materials such as aluminum, copper, zinc, tin, and silver, and oxides such as aluminum oxide, silicon oxide, zinc oxide, tin oxide, magnesium oxide, and titanium oxide.

  When the deposited film thickness is such a thickness that allows light to pass therethrough, the light transmittance can be measured with an optical densitometer and set according to the purpose of the product to be used. Further, when the deposited film thickness is increased and the amount of transmitted light is reduced, the deposited film thickness can be set by the resistance value of the deposited film with an eddy current meter. Furthermore, it is also possible to measure and set the vapor deposition film thickness from the element amount of the vapor deposition material using a fluorescent X-ray meter. Using these methods, it is possible to set the vapor deposition film thickness according to the use, preferably from 100 angstroms to 3 μm.

  Examples of the web-like deposition material used in the present invention include plastic film, paper, and cloth.

  Plastic films include unstretched or at least unidirectionally stretched polyethylene terephthalate film, polyethylene naphthalate film, polypropylene film, polyamide film, polyimide film, polyphenylene sulfide film, polycarbonate film, and their copolymer films and polymers. For example, blended film. Further, at least one surface of these plastic films may be coated with a resin, or a corona discharge treatment or a plasma treatment may be performed. The thickness of the plastic film is usually preferably in the range of 0.5 μm to 500 μm for winding in a roll shape, but differs depending on the characteristics of various plastic films. Is applicable. The same applies to paper and cloth.

  The vapor deposition film thickness control method for a web-like vapor-deposited material according to the present invention is a vapor deposition applied when a vapor deposition material is vacuum-deposited on a continuous web-like vapor-deposited material such as plastic film, paper and cloth by a continuous vacuum vapor deposition apparatus. It is a film thickness control method, and the obtained vapor-deposited material is suitably used for food packaging films, display labels, heat ray reflective films, moisture-proof vapor-deposited paper, and the like.

  Hereinafter, the vapor deposition film thickness control method of the web-shaped vapor deposition material of the present invention will be described in detail based on examples.

Example 1
A vacuum vapor deposition apparatus having a structure shown in FIG. 1 (a roll type vacuum vapor deposition apparatus EW series manufactured by ULVAC) was used.

  The vapor deposition film thickness control of the present invention is as follows: (a) starting vapor deposition and accelerating the speed V of the web-shaped vapor deposition material from the running speed Vs of the web-shaped vapor deposition material at the start of vapor deposition to the steady vapor deposition speed Vt; (B) After the velocity V of the web-like vapor deposition material reached the steady vapor deposition rate Vt, the vapor deposition was performed in two steps of a constant vapor deposition rate Vt.

First, after setting a web-shaped vapor deposition material (“Lumirror” (registered trademark) T70A, Toray Industries, Inc., T70A, thickness 12 μm, width 2 m, length 40000 m) in a vacuum vapor deposition machine, the degree of vacuum in a vacuum chamber by a vacuum pump Was confirmed to have dropped to 3 × 10 ⁻² Pa or less, and deposition was started. Aluminum was used as the dressing material. (A) While vapor deposition is started and the speed V of the web-shaped vapor deposition material is accelerated from Vs (50 m / min) to the steady deposition speed Vt (500 m / min), that is, the speed V of the web-shaped vapor deposition material is When the speed is lower than the steady speed Vt, the heating device power P is increased stepwise in accordance with a program set in advance in the heating power command calculator, that is, the heating device voltage is increased from 10 V to 5 V in 15-second intervals. It was. As the power of the heating device increases, the evaporation amount of the vapor deposition material increases. The deviation Δt between the detection value of the film thickness detector and the preset target film thickness (0.8 in terms of optical density) is calculated, the film thickness deviation Δt is sent to the speed change amount calculator, and the film thickness deviation Δt The speed deviation ΔV proportional to is calculated and sent to the speed command calculator. The speed command calculator sends a new web-like vapor deposition material speed V = (V + ΔV), which is obtained by adding the calculated speed deviation ΔV to the web-like vapor deposition material speed V, to the electric motor. The deposition film thickness is controlled by changing the speed V of the material. By repeating this step, the speed V of the web-like material to be vaporized increases as the power P of the heating device increases while the vapor deposition film thickness is controlled to be constant.

  (B) When it is determined that the web speed V detected by the speed detector by the speed deviation calculator has reached the steady deposition speed Vt (500 m / min), the speed change command calculator calculates the speed V of the web-like deposition material. Is commanded to the motor so as to keep Vt at 500 m / min. The deviation Δt between the detected value of the film thickness detector and the preset target film thickness is calculated, the film thickness deviation Δt is sent to the heating power change amount side, and the heating power deviation Δ proportional to the film thickness deviation Δt is calculated. P is calculated and sent to the superheat power command calculator. The heating power command computing unit sent the new power P = (P + ΔP) obtained by adding the calculated power deviation ΔP to the heating power P to the heating device, and controlled the deposition film thickness by changing the heating power. . As a result, as shown in FIG. 4, the deposition film thickness could be kept uniform (0.8 ± 0.1) from the deposition start rate to the steady deposition rate.

(Comparative Example 1)
Similarly to Example 1, a vacuum deposition apparatus (ULVAC) having the structure shown in FIG. 1 was used. From the deposition start speed Vs to the steady deposition speed Vt, the deviation Δt between the detection value of the film thickness detector and the preset target film thickness is calculated, and the film thickness deviation Δt is sent to the heating power change amount calculator. The heating power deviation ΔP proportional to the film thickness deviation Δt was calculated and sent to the superheat power command calculator. The heating power command computing unit sent the new power P = (P + ΔP) obtained by adding the calculated power deviation ΔP to the heating power P to the heating device, and controlled the film thickness by changing the heating power. First, after setting a web-shaped vapor deposition material (“Lumirror” (registered trademark) T70A, Toray Industries, Inc., T70A, thickness 12 μm, width 2 m, length 40000 m) in a vacuum vapor deposition machine, the degree of vacuum in a vacuum chamber by a vacuum pump Was confirmed to be 3 × 10 −2 Pa or less, and deposition was started. While increasing the rate from the deposition start rate Vs (50 m / min) at a constant rate of 20 m / min, the steady deposition rate Vt was accelerated to 500 m / min. As a result, as shown in FIG. The increase in the amount of evaporation from the crucible did not follow, and the deposited film thickness became non-uniform at the acceleration portion, which was outside the optical density target range (0.8 ± 0.1).

  The method for controlling the deposition thickness of the web-shaped vapor deposition material according to the present invention is a method in which vapor deposition is performed during acceleration from the vapor deposition start speed to the steady vapor deposition speed when vapor deposition is performed on a continuous web-shaped vapor deposition material. This is a method capable of keeping the vapor deposition film thickness uniform from the portion to be processed to the vapor deposition processing at the steady vapor deposition rate, and can reduce the vapor deposition loss and improve the productivity.

FIG. 1 is a side sectional view for illustrating a vacuum deposition apparatus used in the present invention. FIG. 2 is a control block diagram for explaining a control method during which the traveling speed V of the web-like deposition target material is lower than the traveling speed Vt during steady deposition. FIG. 3 is a control block diagram for explaining a control method after the traveling speed V of the web-shaped vapor deposition material reaches the traveling speed Vt during steady deposition. FIG. 4 is a diagram showing the state of the deposited film thickness in Example 1. FIG. 5 is a diagram showing the state of the deposited film thickness in Comparative Example 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum tank 2 Unwinding device 3 Winding device 4 Cooling roll 5 Conveying roll 6 Crucible
7 Vapor deposition material 8 Heating device 9 Shutter 10 Motor 11 Speed detector 12 Vapor deposition thickness detector 13 Vapor deposition thickness control device 14 Web-like vapor deposition material 15 Vacuum pump

Claims (2)

  In a vacuum vapor deposition apparatus for vapor deposition using a heating means for heating and evaporating a vapor deposition material on at least one surface of a continuous web-like vapor deposition material under reduced pressure, the vapor deposition film thickness on the surface of the web-like vapor deposition material is detected. When controlling the vapor deposition film thickness based on the vapor deposition film thickness detection means and the value detected by the vapor deposition film thickness detection means, the travel speed of the web-like material to be deposited is from the start of vapor deposition to the travel speed during steady vapor deposition. While accelerating, the amount of electric power for heating and evaporating the vapor deposition material is increased stepwise by a preset program, while the web-shaped vapor deposition material is deduced from the deviation between the detection value of the vapor deposition film thickness detection means and the target film thickness. A method for controlling a deposited film thickness of a web-like deposition material, wherein the traveling speed is controlled.   After the traveling speed of the web-like deposition material reaches the traveling speed during steady deposition, the detected value of the deposition film thickness detecting means and the target film are maintained while maintaining the traveling speed of the web-like deposition material at the speed during steady deposition. 2. The method of controlling a deposited film thickness of a web-shaped deposition target material according to claim 1, wherein the amount of introduced electric power is controlled from the thickness deviation.

Images