Method for manufacturing polarizing film using ultrasonic vibrator for atomizing coating solution

Abstract

Disclosed herein are a polarizing film manufacturing method including (a) injecting a coating solution containing a component functioning as a polarizer into a sealed chamber to form an injection condition of the coating solution, (b) supplying a polyvinyl alcohol film into the chamber and dyeing outer surfaces of the polyvinyl alcohol film with the coating solution, and (c) discharging the polyvinyl alcohol film dyed with the coating solution out of the chamber, a polarizing film manufacturing apparatus, and a polarizing film exhibiting improved optical properties manufactured using the same.

Claims

1. A polarizing film manufacturing method comprising: (a) injecting a coating solution into a sealed chamber by atomizing the coating solution using an ultrasonic vibrator and carrying the atomized coating solution into the chamber using a carrier gas, the coating solution including a component functioning as a polarizer, wherein process (a) comprises injecting the coating solution using an ultrasonic injection method or an ultrasonic spray injection method; (b) supplying a polyvinyl alcohol film into the chamber and dyeing outer surfaces of the polyvinyl alcohol film with the atomized coating solution in the chamber; and (c) discharging the polyvinyl alcohol film dyed with the coating solution out of the chamber, wherein the coating solution is injected while an ultrasonic wave of 10 Hz to 100 Hz is applied to the coating solution.

2. The polarizing film manufacturing method according to claim 1, wherein the coating solution containing the component functioning as the polarizer is an aqueous solution containing iodine.

3. The polarizing film manufacturing method according to claim 1, wherein the coating solution injected into the chamber has a concentration of 10.sup.5 mole/liter to 10.sup.1 mole/liter.

4. The polarizing film manufacturing method according to claim 1, wherein the polyvinyl alcohol film is moved in the chamber and out of the chamber by rotary rolls.

5. The polarizing film manufacturing method according to claim 4, wherein two or more of the rotary rolls simultaneously contact an upper surface and a lower surface of the polyvinyl alcohol film.

6. The polarizing film manufacturing method according to claim 1, wherein the polyvinyl alcohol film is dyed with the coating solution while being moved in the chamber at a speed of 0.5 m/min to 40 m/min.

7. The polarizing film manufacturing method according to claim 1, wherein the polyvinyl alcohol film is moved in the chamber along one or more selected from a group consisting of a linear movement route, a V-shaped movement route, and a U-shaped movement route.

8. The polarizing film manufacturing method according to claim 1, wherein the coating solution is injected in a direction identical to or opposite to an advancing direction of the polyvinyl alcohol film.

9. The polarizing film manufacturing method according to claim 1, further comprising elongating the polyvinyl alcohol film dyed with the coating solution.

10. The polarizing film manufacturing method according to claim 9, wherein the elongating process comprises elongating the polyvinyl alcohol film at a elongating ratio of 1.5 to 6.

11. A polarizing film manufactured using a polarizing film manufacturing method according to claim 1.

12. The polarizing film according to claim 11, wherein the polarizing film has a degree of polarization of 99.95% or higher.

13. A polarizing sheet manufactured by attaching protective films to an upper surface and a lower surface of a polarizing film according to claim 11.

14. The polarizing sheet according to claim 13, wherein each of the protective films is a triacetyl cellulose film.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

(2) FIG. 1 is a typical view showing a polarizing film manufacturing apparatus according to an embodiment of the present invention;

(3) FIG. 2 is a typical plan view showing a method of manufacturing a polarizing film using the polarizing film manufacturing apparatus of FIG. 1;

(4) FIG. 3 is a typical plan view showing a method of manufacturing a polarizing film according to another embodiment of the present invention; and

(5) FIG. 4 is a typical plan view showing a method of manufacturing a polarizing film according to a further embodiment of the present invention.

BEST MODE

(6) Now, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted, however, that the scope of the present invention is not limited by the illustrated embodiments.

(7) For the convenience of understanding, only some components of a polarizing film manufacturing apparatus are shown in the drawings, and other components of the polarizing film manufacturing apparatus are omitted from the drawings.

(8) FIG. 1 is a typical plan view showing a polarizing film manufacturing apparatus according to the present invention.

(9) Referring to FIG. 1, a polarizing film manufacturing apparatus 100 according to the present invention includes an inlet port 110, through which a polyvinyl alcohol film is introduced, an outlet port 120, through which the polyvinyl alcohol film is discharged, rotary rolls 130 for moving the polyvinyl alcohol film in a state of contacting one surface of the polyvinyl alcohol film, and an ultrasonic vibrator 140 for injecting an iodine aqueous solution.

(10) Specifically, an aqueous solution containing iodine functioning as a polarizer may be injected into a chamber 101 using the ultrasonic vibrator 140. In this case, the inlet port 110 and the outlet port 120 of the chamber 101 may be in a closed state, and the magnitude of an ultrasonic wave and an injection speed of the a coating solution injected into the sealed chamber may be properly adjusted such that the coating solution in the sealed chamber has a concentration of 10.sup.5 mole/liter to 10.sup.1 mole/liter. For example, an ultrasonic wave of 10 Hz to 100 Hz may be applied to inject an aqueous solution containing iodine into the chamber 101.

(11) The number and position of the rotary rolls 130 in the chamber 101 are not particularly restricted, and the rotary rolls 130 may be located at proper positions in the chamber 101 in order to move the polyvinyl alcohol film.

(12) FIG. 2 is a typical plan view showing a method of manufacturing a polarizing film using the polarizing film manufacturing apparatus of FIG. 1.

(13) Referring to FIG. 2, during the movement of a polyvinyl alcohol film 150 through the inlet port 110 and the outlet port 120 of the chamber 101, surfaces of the polyvinyl alcohol film 150 may be dyed according to an injection condition of an aqueous solution containing iodine formed in the chamber 101.

(14) The rotary rolls 130 may be located at proper positions in the chamber 101 in order to properly move the polyvinyl alcohol film 150 in a direction indicated by an arrow, and the number and position of the rotary rolls 130 in the chamber 101 are not particularly restricted. For example, two or more of the rotary rolls may simultaneously contact the upper surface and the lower surface of the polyvinyl alcohol film 150.

(15) The moving speed of the polyvinyl alcohol film 150 and the injection speed of iodine injected by the ultrasonic vibrator 140 may be properly adjusted to properly adjust the amount of iodine dyed to the surfaces of the polyvinyl alcohol film 150.

(16) As compared with a dry type process and a wet type process, a proper amount of iodine may be uniformly dyed to the surfaces of the polyvinyl alcohol film 150, whereby it is possible to manufacture a polarizing sheet exhibiting high optical properties.

(17) FIG. 3 is a typical plan view showing a method of manufacturing a polarizing film according to another embodiment of the present invention.

(18) A polarizing film manufacturing apparatus 200 shown in FIG. 3 includes an ultrasonic vibrator 240 for injecting an iodine aqueous solution and a blower 250.

(19) The ultrasonic vibrator 240 may inject the iodine aqueous solution in a direction identical to or opposite to an advancing direction of a polyvinyl alcohol film. The blower 250 may be located so as to effectively disperse the iodine aqueous solution injected by the polarizing film manufacturing apparatus. The position and number of the blower 250 and the ultrasonic vibrator 240 are not particularly restricted.

(20) FIG. 4 is a typical plan view showing a method of manufacturing a polarizing film according to a further embodiment of the present invention.

(21) Referring to FIG. 4, a polyvinyl alcohol film 151 may move in the chamber along a mixed route consisting of a linear movement route and a V-shaped movement route. The movement route is not particularly restricted so long as the polyvinyl alcohol film 15 is effectively dyed.

INDUSTRIAL APPLICABILITY

(22) As is apparent from the above description, a polarizing film manufacturing method according to the present invention includes a process of dyeing iodine using an ultrasonic spray process, whereby it is possible to greatly reduce the amount of an iodine aqueous solution that is used as compared with a conventional process. In addition, the surfaces of a polyvinyl alcohol member may be uniformly dyed with the minimum amount of iodine that is capable of exhibiting polarizing properties, whereby it is possible to minimize surface defects, such as wrinkles, and thus to improve optical properties of a polarizing film that is manufactured.

(23) Although the exemplary embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.