KR20170117429A - A defect inspection method of a laminated optical film, a defect inspection method of an optical film, and a manufacturing method of a laminated optical film - Google Patents

Abstract

The method for inspecting a defect in a laminated optical film provided in the present invention includes a first inspection step of inspecting a defect of the optical film 11 and a second inspection step of bonding a protective film 12 and an adhesive material 13 to the optical film 11 A recording step of recording the information of the defects 20 detected in the first inspection step as a code 40 in the laminated optical film 10A; a step of recording information of the defects 20 detected in the first inspection step in the laminated optical film 10A; A second inspection step of performing defect inspection on the laminated optical film 10B in accordance with the defects 20 detected in the first inspection step and the defects 21 detected in the second inspection step And in the second inspecting step, defect information recorded in the recording step is read out, and the defects 20 corresponding to the defect information are not duplicatedly detected.

Description

A defect inspection method of a laminated optical film, a defect inspection method of an optical film, and a manufacturing method of a laminated optical film

The present invention relates to a defect inspection method for a laminated optical film and a defect inspection method for an optical film, and also relates to a method for producing a laminated optical film.

As an optical film having optical properties, a polarizing plate having polarization characteristics and a retardation plate having birefringence are known. For example, as a polarizing plate, it is known that a TAC (triacetyl cellulose) film is bonded to both sides of a main surface of a polarizing film (polyvinyl alcohol (PVA) as an optical film body. As a phase difference plate, it is known that the phase difference plate is composed of an optical film body alone. In this kind of optical film, a protective film may be bonded, or an adhesive material in a state in which a separate film is attached may be bonded to form a laminated optical film.

In this kind of optical film and laminated optical film, for example, optical defects may be generated when foreign matter or air bubbles are mixed in the inside or the surface at the time of bonding. Patent Documents 1 and 2 disclose a method for inspecting defects in an optical film and a laminated optical film of this kind.

When a defect is detected by this type of defect inspection method, marking is performed on the surface of the optical film and the laminated optical film so as to surround the defect, for example, in accordance with the defect, and the marked area is excluded from use as a product .

Japanese Patent Application Laid-Open No. 2009-69142 Japanese Patent Laid-Open No. 11-65184

In such a defect inspection method, it is required to accurately count the number of defects. The mark to be marked is required to have a size corresponding to the size of the defect.

Incidentally, in the defect inspection of this type of optical film and the laminated optical film, there are cases where the defect inspection is performed twice or more. For example, there is a case where defect inspection is performed every time the respective layers of the optical film and the laminated optical film are bonded, or different inspection methods are performed in order to detect different defects.

However, when two or more defects are inspected, defects detected before the last inspection are duplicatedly detected in the second inspection and thereafter, and the defect rate can not be obtained with high accuracy. In the second and subsequent inspections, the marks previously marked before are detected as defects and are marked corresponding to them (for example, to surround the defects), resulting in a problem that the final mark size is increased.

Thus, the present invention provides a defect inspection method and a defect inspection method for a defect in a laminated optical film capable of preventing duplicate detection of a defect detected before the last time, and detecting a mark corresponding to a defect detected before the last time, An inspection method and a defect inspection method for an optical film. It is also an object of the present invention to provide a method for producing a laminated optical film.

A defect inspection method for a laminated optical film of the present invention is a method for inspecting defects in a laminated optical film while obtaining a laminated optical film by bonding at least one of a protective film and an adhesive to an optical film, A step of forming a laminated optical film by bonding at least one of a protective film and an adhesive to an optical film; a recording step of recording defect information detected in the first inspection step; And a marking step of marking the laminated optical film in accordance with the defect detected in the first inspection step and the defect detected in the second inspection step, In the process, the defect information recorded in the recording process is read, and a defect corresponding to the defect information is not detected.

According to the defect inspection method of this laminated optical film, in the second inspection step, defects corresponding to the defect information recorded in the recording step are not detected. Therefore, when two or more defects are inspected, it is possible to prevent duplicate detection of defects detected before the last time. According to the defect inspection method of the laminated optical film, defect information detected in the first inspection step is recorded in the recording step, and the defect information detected in the first inspection step before the second inspection step is recorded on the optical film Since marking is not performed, it is possible to prevent the mark corresponding to the defect detected before the last time from being detected.

The defect inspection method in the first inspection step and the defect inspection method in the second inspection step may be the same or different.

A defect inspection method for an optical film of the present invention is a method for inspecting defects of an optical film, comprising: a first inspection step of performing defect inspection of an optical film; a recording step of recording defect information detected in the first inspection step; A second inspection step for performing defect inspection different from the defect inspection in the first inspection step for the optical film, a defect detected in the first inspection step, and a defect detected in the second inspection step And a marking step of performing marking on the optical film. In the second inspection step, defect information recorded in the recording step is read, and a defect corresponding to the defect information is not detected.

The optical film of the present invention includes not only a single-layer optical film composed of the optical film main body but also an optical film including the optical film main body and a laminated optical film obtained by bonding at least one of a protective film and an adhesive material to the optical film .

In the defect inspection method of this optical film, since the defect corresponding to the defect information recorded in the recording step is not detected in the second inspection step, when defect inspection is performed two or more times, Can be prevented. In the defect inspection method of this optical film, the defect information detected in the first inspection step is recorded in the recording step so that marking is not performed on the optical film corresponding to the defect detected in the first inspection step before the second inspection step Therefore, it is possible to prevent the mark corresponding to the defect detected before the last time from being detected.

The method for producing a laminated optical film of the present invention is a method for producing a laminated optical film by bonding at least one of a protective film and an adhesive to an optical film, and includes a defect inspection method for the above laminated optical film. According to this method for producing a laminated optical film, the same advantages as the defect inspection method for the above-mentioned laminated optical film can be obtained.

According to the present invention, when the defect inspection of the optical film and the laminated optical film is performed twice or more, it is possible to prevent duplicate detection of the defect detected before the last time, and as a result, the defect rate can be obtained with high precision. Further, according to the present invention, it is possible to prevent a mark corresponding to a defect detected before the last time from being detected when the defect inspection of the optical film and the laminated optical film is performed two or more times. As a result, It is possible to prevent the yield of the optical film from deteriorating.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a diagram showing a defect inspection method and a manufacturing method of a laminated optical film according to a first embodiment of the present invention. FIG.
2 is a diagram showing a defect inspection method and a manufacturing method of a laminated optical film according to the first embodiment of the present invention.
3 is a view for explaining a recording step in a defect inspection method of a laminated optical film according to the first embodiment of the present invention, and shows one main surface of the laminated optical film.
4 is a cross-sectional view of the laminated optical film along the line IV-IV in Fig.
Fig. 5 is a view for explaining a marking step in a defect inspection method of a laminated optical film according to the first embodiment of the present invention, showing one main surface of a laminated optical film. Fig.
6 is a cross-sectional view of the laminated optical film along the line VI-VI in Fig.
7 is a view for explaining a first marking step in a conventional defect inspection method, showing one main surface of a laminated optical film in a conventional defect inspection method.
8 is a cross-sectional view of the laminated optical film taken along the line VIII-VIII in Fig.
Fig. 9 is a view for explaining the second marking step in the conventional defect inspection method, showing one main surface of the laminated optical film in the conventional defect inspection method. Fig.
10 is a sectional view of the laminated optical film along the line XX in Fig.
11 is a view showing a defect inspection method and a manufacturing method of a laminated optical film according to a second embodiment of the present invention.
12 is a view showing a defect inspection method and a manufacturing method of a laminated optical film according to a second embodiment of the present invention.
13 is a view for explaining a recording step in a defect inspection method for a laminated optical film according to a second embodiment of the present invention, showing one main surface of a laminated optical film.
14 is a cross-sectional view of the laminated optical film along the line XIV-XIV in Fig.
Fig. 15 is a view for explaining the marking step in the defect inspection method of the laminated optical film according to the second embodiment of the present invention, showing one main surface of the laminated optical film. Fig.
16 is a cross-sectional view of the laminated optical film along the line XVI-XVI in Fig.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or equivalent parts are denoted by the same reference numerals.

[First Embodiment]

1 and 2 are views showing a defect inspection method and a manufacturing method of a laminated optical film according to the first embodiment of the present invention. Figs. 3 and 5 are views showing one main surface of the laminated optical film in the different steps of the defect inspection method according to the first embodiment of the present invention, and Fig. 4 and Fig. 6 are views Sectional view of a laminated optical film. Figs. 1 to 6 show XY plane coordinates. The X direction indicates the width direction of the laminated optical film, and the Y direction indicates the length direction of the laminated optical film.

First, as shown in Fig. 1, the optical film 11 is unwound from the original roll 101. Then, as shown in Fig. The optical film (11) includes an optical film main body having optical characteristics. Examples of the optical film 11 include a polarizing plate having polarization characteristics and a retardation plate having birefringence. For example, when the optical film 11 is a polarizing plate, the optical film 11 includes a polyvinyl alcohol (PVA) as an optical film body, and a TAC (triacetyl cellulose) film is bonded to both sides of the polarizer. On the other hand, when the optical film 11 is a phase difference plate, the phase difference plate corresponds to the optical film main body.

Subsequently, light is irradiated onto the optical film 11 by a light source (not shown) disposed on the other main surface 11b side of the optical film 11, and light is irradiated onto one main surface 11a of the optical film 11, And the defect inspection of the optical film 11 is performed based on the received transmitted light (the first inspection step, the second inspection step, and the second inspection step) Permeability test).

Subsequently, the protective film 12 is unwound from the disk roll 102, and the protective film 12 is laminated on the side of the main surface 11a of the optical film 11. As the protective film 12, a PET (polyethylene terephthalate) film or the like is used. Subsequently, the optical film 11 and the protective film 12 are bonded to each other by the bonding roll 103 to produce a laminated optical film 10A.

Subsequently, the information (defect information) of defects detected in the first inspection step is read out by a code (by a droplet method) using an inkjet printer 113 disposed on the protective film 12 side of the laminated optical film 10A Is recorded on the surface end portion of the laminated optical film 10A on the protective film 12 side (recording step).

3 and 4, when three defects 20 are detected due to foreign matter being mixed in the laminated optical film 10A, the coordinate information of these defects 20 is recorded in the barcode 40, , The defects 20 are recorded in the X direction end portion of the surface of the laminated optical film 10A on the protective film 12 side. 4 and Fig. 1 schematically show only one defect 20 in Fig. 3 and a barcode 40 corresponding to the defect 20. In Fig.

One bar code 40 may be recorded every predetermined interval in the Y direction (for example, every 60 mm intervals). In this case, all of the defects existing in a predetermined section may be collected and recorded in one bar code 40. FIG.

Subsequently, the laminated optical film 10A is wound around the disk roll 104. Then,

Subsequently, the laminated optical film 10A is unwound from the disk roll 104 and a separate film (release film) 14 is removed from the disk roll 105, as shown in Fig. 2 The adhesive material 13 with the separate film bonded to the adhesive material 15 is released and the adhesive material 13 with the separate film attached to the optical film 11 side of the laminated optical film 10A is laminated. As the material of the separate film, PET (polyethylene terephthalate) or the like is used. Subsequently, the laminated optical film 10A and the adhesive material 13 having the separate film attached thereto are bonded together by the bonding roll 106 to produce a laminated optical film 10B.

Subsequently, light (not shown) disposed on the other main surface 10b side (the side of the adhesive material 13 to which the separate film is attached) of the laminated optical film 10B is irradiated with light And the light transmitted through the laminated optical film 10B is received by the inspection device 115 disposed on the side of the main surface 10a (on the side of the protective film 12) of the laminated optical film 10B, The defect inspection of the laminated optical film 10B is performed based on one transmitted light (second inspection step, transmission inspection). In the first embodiment, the tester 115 is a transmission tester.

In the second inspection step, the code reader 117 reads the defect information recorded in the bar code 40 in the recording step, and does not detect the defect 20 corresponding to the read defect information. That is, in the second inspection step, the defect 21 which is not detected in the first inspection step and is detected for the first time in the second inspection step is detected (see FIGS. 5 and 6). Specifically, in the second inspection step, a defect at the same position as the defect coordinates read from the bar code 40 is determined as the same defect and is not detected.

Subsequently, defects detected in the first inspection step (that is, from the barcode 40) are detected by using the inkjet printer 119 (by the droplet method) disposed on the side of the main surface 10a of the laminated optical film 10B Marking is performed on the surface of the laminated optical film 10B on the side of one main surface 10a in accordance with the defects detected in the first inspection step and the defects detected in the second inspection step.

For example, as shown in Figs. 3 and 4, in the first inspection step, three defects 20 which are generated when foreign matters are mixed in the laminated optical film 10A are detected, and as shown in Figs. 5 and 6 When two defects 21 generated by the foreign substance mixed in the inside of the laminated optical film 10B are detected in the second inspection step as described above, 21a of the laminated optical film 10B so as to surround the defects 20 and 21 so as to sandwich the defects 20 and 21 by marking the linear mark 31 in the Y direction. The marking is performed.

6 schematically shows one defect 20 in Fig. 5 and two linear marks 31 corresponding to the defect 20 and one defect 21 in Fig. 5, , And two linear marks 31 corresponding to the defects 21. As shown in Fig. 2 schematically shows only one defect 20 or 21 in Fig. 5 and two linear marks 31 corresponding to this defect 20 or 21. Fig.

Subsequently, the laminated optical film 10B is wound around the disk roll 107. Then,

7 and 9 are views showing one main surface of the laminated optical film in the different processes of the conventional defect inspection method, and Figs. 8 and 10 are sectional views of the laminated optical film shown in Figs. 7 and 9 to be.

In the conventional defect inspection method, the first marking step and the second marking step are provided instead of the recording step and the marking step in the present embodiment, and in the second inspection step, defects detected in the first inspection step are detected The defect inspection method of the present embodiment differs from the defect inspection method of the present embodiment in that it does not have a function of not performing defect inspection.

In the first marking step, for example, when three defects 20 produced by the incorporation of foreign matter into the inside of the laminated optical film 10A are detected as shown in Figs. 7 and 8, The linear mark 30 is marked on the both sides in the X direction with respect to the Y direction so as to surround the defect 20 so as to sandwich the defect 20. In other words, 12) side is marked.

In the second marking step, for example, as shown in Figs. 8 and 10, when two defects 21 are detected, which are caused by the incorporation of foreign matter into the laminated optical film 10B, The linear mark 31 is marked on the both sides in the X direction with respect to the Y direction so as to surround the defect 21 so as to sandwich the defect 21. In other words, Marking is carried out on the surface of the substrate 10a.

In this conventional defect inspection method, as shown in Figs. 8 and 10, in the second inspection step, the defects 20 in the first inspection step are detected again, and marks 30 ) As a defect. As a result, in the second marking step, corresponding to the defects 20 detected in the first inspection step and the marks 30 formed in the first marking step, the defects 20 and the marks 30 are sandwiched in correspondence with the marks 30 formed in the first marking step. The mark 31 is formed so as to surround the defect 20 and the mark 30 in other words.

As described above, in the conventional defect inspection method, when two or more defects are inspected, the defects detected before the last time are duplicatedly detected in the second and subsequent inspection, and the defect rate can not be obtained with high accuracy . Further, in the second and subsequent inspection, a mark previously marked before is detected as a defect, and corresponding mark is further marked in the vicinity of the defect. As a result, the final mark size is increased and the yield of the optical film is lowered .

However, according to the defect inspection method of the laminated optical film of the first embodiment, since the defect corresponding to the defect information recorded in the recording step is not detected in the second inspection step, when defect inspection is performed twice or more, It is possible to prevent duplicate detection of the previously detected defects 20, and as a result, the defect rate can be obtained with high precision. According to the defect inspection method of the laminated optical film of the first embodiment, defect information detected in the first inspection step is recorded as the bar code 40 in the recording step, so that in the first inspection step before the second inspection step It is possible to prevent the marks corresponding to the defects detected before the last time from being detected because marking is not performed on the optical film corresponding to the detected defects 20. [ Therefore, the yield of the optical film due to the increase in the final mark size can be prevented.

[Modifications of First Embodiment]

In the first embodiment, the same kind of defect inspection (penetration inspection) is performed plural times before and after the step of bonding the protective film 12 and the adhesive material 13 with the separate film to the optical film 11 . However, the idea of the present invention is that, as will be described in detail below, different types of defect inspection are combined, for example, in the first embodiment, the penetration inspection is performed as the first inspection step, It is also applicable to a form in which reflection inspection is performed.

[Second Embodiment]

In the first embodiment, a method of performing a plurality of defect inspections before and after the step of bonding the protective film 12 and the adhesive material 13 with the separate film to the optical film 11 is exemplified. However, The mapping can also be applied to a method in which a plurality of defects are inspected for the same laminated optical film.

For example, different inspection (for example, transmission inspection and reflection inspection) may be performed in combination for the same laminated optical film. For example, the penetration test is suitable for the detection of foreign matter of the black color mixed in the inside of the optical film, but it is difficult to detect small bubbles incorporated into the surface of the optical film. On the other hand, the reflection inspection is suitable for the detection of small bubbles incorporated into the surface of the optical film, but it is difficult to detect the foreign matter of black color mixed into the optical film.

Hereinafter, a defect inspection method which is performed by combining different tests for the same laminated optical film will be exemplified. In this second embodiment, a defect inspection method of a laminated optical film is exemplified. However, the idea of the present invention is also applicable to a defect inspection method in which different tests are combined for a single-layer optical film.

11 and 12 are diagrams showing a defect inspection method and a manufacturing method of a laminated optical film according to a second embodiment of the present invention. 13 and 15 are views showing one main surface of a laminated optical film in a different step of the defect inspection method of the laminated optical film according to the second embodiment of the present invention, 15 is a sectional view of the laminated optical film shown in Fig.

First, as shown in Fig. 11, the laminated optical film 10B is unwound from the disk roll 101. Then, as shown in Fig. The laminated optical film 10B is irradiated with light by a light source (not shown) disposed on the other main surface 10b side of the laminated optical film 10B, The transmission inspection tester 111 disposed on the side of the laminated optical film 10a receives the light transmitted through the laminated optical film 10B and performs defect inspection of the laminated optical film 10B based on the received transmitted light , Transmission test).

Subsequently, the defect information detected in the first inspection step is used as a code by using an inkjet printer 113 (by a droplet method) arranged on one main surface 10a side of the laminated optical film 10B as a code, (Recording process) on the protective film 12 side of the recording medium 10A.

13 and 14, when three defects 20 are detected due to foreign matter being mixed in the laminated optical film 10B, the coordinate information of the defects 20 is detected by the barcode 40, , The defects 20 are recorded in the X direction end portion of the surface of the laminated optical film 10A on the protective film 12 side. In Figs. 14 and 11, only one defect 20 in Fig. 13 and a barcode 40 corresponding to the defect 20 are schematically shown.

Subsequently, the laminated optical film 10B is wound on the master roll 104. Then,

Subsequently, as shown in Fig. 12, the laminated optical film 10B is unwound from the disk roll 104. Then, as shown in Fig. Subsequently, the laminated optical film 10B is irradiated with light by a light source (not shown) disposed on the side of the main surface 10a of the laminated optical film 10B, The tester 115 disposed on the side of the stacked optical film 10a receives the light reflected by one main surface 10a of the laminated optical film 10B and performs defect inspection of the laminated optical film 10B based on the received reflected light (Second inspection step, reflection inspection). In the second embodiment, the tester 115 is a reflection tester.

In the second inspection step, the code reader 117 reads the defect information recorded in the bar code 40 in the recording step, and does not detect the defect 20 corresponding to the read defect information. That is, in the second inspection step, the defect 25 which is not detected in the first inspection step and is detected for the first time in the second inspection step is detected (see Figs. 15 and 16). Specifically, in the second inspection step, a defect at the same position as the defect coordinates read from the bar code 40 is determined as the same defect and is not detected.

Subsequently, defects detected in the first inspection step (that is, from the barcode 40) are detected by using the inkjet printer 119 (by the droplet method) disposed on the side of the main surface 10a of the laminated optical film 10B Marking is performed on the surface of the laminated optical film 10B on the side of one main surface 10a in accordance with the defects detected in the first inspection step and the defects detected in the second inspection step.

For example, as shown in Figs. 13 and 14, in the first inspection step, three defects 20 which are generated when foreign matters are mixed in the laminated optical film 10B are detected, and as shown in Figs. 15 and 16 In the second inspection step, when two defects 25 produced by the incorporation of bubbles into the surface of the laminated optical film 10B are detected, The linear mark 31 is marked in the Y direction so as to surround the defects 20 and 25 so as to sandwich the defects 20 and 25. In other words, The marking is performed.

16 schematically shows one defect 20 in FIG. 15 and two linear marks 31 corresponding to the defect 20, and one defect 25 in FIG. And two linear marks 31 corresponding to the defects 25. As shown in Fig. In Fig. 12, only one defect 20 or 25 in Fig. 15 and two linear marks 31 corresponding to the defect 20 or 25 are schematically shown.

Subsequently, the laminated optical film 10B is wound around the disk roll 107. Then,

The same advantages as those of the defect inspection method and the manufacturing method of the laminated optical film of the first embodiment can be obtained in the defect inspection method and manufacturing method of the laminated optical film of the second embodiment.

The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, in the present embodiment, the defect inspection is performed twice, but the idea of the present invention is also applicable to the defect inspection performed three times or more.

In the present embodiment, penetration inspection and reflection inspection are exemplified as types of defect inspection, but the kind of defect inspection is not limited to this. The idea of the present invention is also applicable to a defect inspection method including Cross-Nicol inspection and the like.

The coordinate information of the detected defects 20 is recorded in the laminated optical film 10A as the barcode 40 in the recording process but the coordinate information of the detected defects 20 is It may be recorded in a memory such as a computer. In the present embodiment, the coordinate information of the defect recorded in the bar code 40 is read by the code reader 117 in the second inspection step. However, in the second inspection step, Information may be read.

10A, 10B: laminated optical film 11: optical film
12: protective film 13: adhesive material with separate film
14: Separate film 15: Adhesive material
20, 21, 25: defect 30, 31: mark
40: bar code (code) 101, 102, 104, 105, 107:
103, 106: bonding roll 111: transmission inspection machine
113, 119: Ink-jet printer
115: Inspector (Transmission Inspector or Reflector Inspector)
117: Code reader

Claims (5)

A method for inspecting defects in the above laminated optical film while bonding a protective film and an adhesive to at least one of the optical films to obtain a laminated optical film,
A first inspection step of performing defect inspection of the optical film;
Forming at least one of the protective film and the adhesive material on the optical film to produce the laminated optical film,
A recording step of recording defect information detected in the first inspection step;
A second inspection step of performing defect inspection of the laminated optical film,
A marking step of marking the laminated optical film corresponding to a defect detected in the first inspection step and a defect detected in the second inspection step
/ RTI >
In the second inspection step, the defect information recorded in the recording step is read, and a defect corresponding to the defect information is not detected
(Method for Inspection of Defects in Laminated Optical Film). The defect inspection method for a laminated optical film according to claim 1, wherein the defect inspection method in the first inspection step and the defect inspection method in the second inspection step are the same. The defect inspection method for a laminated optical film according to claim 1, wherein the defect inspection method in the first inspection step and the defect inspection method in the second inspection step are different. A method for inspecting defects in an optical film,
A first inspection step of performing defect inspection of the optical film;
A recording step of recording defect information detected in the first inspection step;
A second inspection step of performing a defect inspection on the optical film different from the defect inspection in the first inspection step;
A marking step of marking the optical film corresponding to a defect detected in the first inspection step and a defect detected in the second inspection step
/ RTI >
In the second inspection step, the defect information recorded in the recording step is read, and a defect corresponding to the defect information is not detected
A defect inspection method for an optical film. A method for producing a laminated optical film by bonding at least one of a protective film and an adhesive to an optical film,
A method for inspecting defects of a laminated optical film according to any one of claims 1 to 3,
A method for producing a laminated optical film.

Images