KR102337780B1 - Polarizing plate and method of fabricating the same, and liquid crystal display device having the same - Google Patents

Abstract

The polarizing plate of the present invention, its manufacturing method, and a liquid crystal display having the same are caused by static electricity and polarizing plate cracking caused by the reduction of the distance between the liquid crystal panel and the backlight unit by reducing the frictional force on the outer surface of the polarizing plate or in the adhesive of the protective film In order to improve one foreign material defect, the substrate; a protective layer formed on at least one side of the substrate; and an antistatic layer formed by adding a fluorine (F)-based polymer or an antistatic component to the outer surface of the protective layer.

Description

Polarizing plate, manufacturing method thereof, and liquid crystal display having same

The present invention relates to a polarizing plate and a method for manufacturing the same, and more particularly, to a polarizing plate suitable for a liquid crystal display capable of implementing a slim and narrow bezel, and a method for manufacturing the same, and to a liquid crystal display having the same .

Recently, as interest in information display is rising and the demand to use portable information media is increasing, a lightweight thin-film flat panel display (FPD) replacing the conventional display device, a cathode ray tube (CRT), has been developed. Research and commercialization are focused on.

In particular, among these flat panel display devices, a liquid crystal display (LCD) is a device that expresses an image using the optical anisotropy of liquid crystal, and has excellent resolution, color display, and picture quality, and is actively applied to notebooks and desktop monitors. have.

The liquid crystal display is driven by two opposing electrodes and a liquid crystal layer formed therebetween, and an electric field generated by applying a voltage to the two electrodes drives liquid crystal molecules in the liquid crystal layer.

Liquid crystal molecules have polarization properties and optical anisotropy. Polarization properties refer to the fact that when the liquid crystal molecules are placed in an electric field, the charges in the liquid crystal molecules are concentrated on both sides of the liquid crystal molecules and the direction of the molecular arrangement changes according to the electric field, and optical anisotropy refers to changing the path or polarization state of the outgoing light differently depending on the incident direction or polarization state of the incident light due to the elongated structure of the liquid crystal molecules and the molecular arrangement direction mentioned above.

Accordingly, the liquid crystal display device has a liquid crystal panel composed of a pair of transparent insulating substrates each having an electric field generating electrode formed on each side facing each other with a liquid crystal layer interposed therebetween, and the electric field change between the electric field generating electrodes is reduced. Through this, the alignment direction of liquid crystal molecules is artificially controlled, and various images are displayed using the changed light transmittance.

At this time, polarizing plates are positioned on the upper and lower portions of the liquid crystal panel, respectively, and the polarizing plate transmits light of a polarization component that coincides with the transmission axis to determine the degree of light transmission by the arrangement of the transmission axes of the two polarizing plates and the arrangement characteristics of the liquid crystal. will do

1A and 1B are exemplary views showing characteristics of light passing through a liquid crystal panel.

Referring to the drawings, a general liquid crystal display device includes a liquid crystal panel 10 and a backlight unit (not shown) supplying light from the rear surface thereof, and the liquid crystal panel 10 has a liquid crystal layer 30 interposed therebetween. The first and second substrates 5 and 15 are bonded together, and the first and second polarizing plates 1 and 11 respectively attached to the outer surfaces of the first and second substrates 5 and 15 are included.

At this time, although not shown, a color filter and a common electrode for realizing color are provided on the inner surface of the first substrate 5, and a plurality of pixels having transparent pixel electrodes formed on the inner surface of the second substrate 15 and each of these pixel electrodes A thin film transistor for controlling on/off of the liquid crystal driving voltage transferred to the ?

In addition, the liquid crystal layer 30 interposed between the first and second substrates 5 and 15 is a TN (twisted nematic) mode. While maintaining parallel to (5, 15), from the first substrate 5 to the second substrate 15, it represents the twisted alignment state at an azimuth angle of 90 degrees, and the polarization axes of the first and second polarizers 1 and 11 are are orthogonal to each other.

Since the liquid crystal panel 10 does not emit light by itself, a backlight unit for supplying light to the liquid crystal panel 10 is located on the rear surface of the liquid crystal panel 10 .

In the liquid crystal panel 10, when the voltage is off, the light emitted from the backlight unit is transmitted by the second polarizing plate 11 by the second polarizing plate 11 as shown in FIG. 1A, and only linearly polarized light is transmitted The remainder is absorbed and rotated by 90 degrees along its azimuth while passing through the liquid crystal layer 30 to pass through the first polarizing plate 1 to display white.

Next, when the voltage is in the on state, the liquid crystal molecules of the liquid crystal panel 10 have a long axis aligned perpendicular to the first and second polarizing plates 1 and 11 as shown in FIG. Optical rotatory power is lost, and the linearly polarized light passing through the second polarizing plate 11 is blocked by the first polarizing plate 1 to display black.

The structure of a general liquid crystal display driven in this way will be described in detail with reference to the drawings.

FIG. 2 is a cross-sectional view schematically showing the structure of a general liquid crystal display, and shows as an example the structure of a liquid crystal display including a direct backlight unit.

As shown in the drawing, a general liquid crystal display device mainly includes a liquid crystal panel 10 and a backlight unit installed on the rear surface of the liquid crystal panel 10 to supply light to the liquid crystal panel 10 .

Although not shown in detail, the liquid crystal panel 10 is a place where an actual image is realized, and includes a transparent first and second substrate such as glass, and a liquid crystal layer formed between the first and second substrates.

The first substrate is a color filter substrate on which a color filter is formed, and the second substrate is a TFT substrate on which driving elements such as thin film transistors and pixel electrodes are formed. In addition, a driving circuit unit is provided on a side surface of the second substrate to apply a signal to each of the thin film transistor and the pixel electrode formed on the second substrate.

The backlight unit includes a lamp 44 that actually emits light, a reflector 43 that reflects the light emitted from the lamp 44 toward the liquid crystal panel 10 to improve light efficiency, and is disposed on the reflector 43 . It is composed of an optical sheet 41 made of a diffusion sheet and a prism sheet.

At this time, since the direct type backlight unit does not use a light guide plate, a diffuser plate is installed between the plurality of lamps 44 and the optical sheet 41 to diffuse the light of the light source and support the optical sheet 41 . (42) is provided.

Polarizing plates 1 and 11 are respectively disposed on the upper and lower surfaces of the liquid crystal panel 10 .

The light emitted from the backlight unit is polarized by the second polarizing plate 11 attached to the second substrate, and the polarization state of the light is converted while passing through the liquid crystal layer, and then through the first polarizing plate 1 attached to the first substrate. is released as At this time, an image is realized by adjusting the transmittance of light transmitted through the first polarizing plate 1 according to a change in the polarization state of light by the liquid crystal layer.

On the upper portion of the backlight unit configured as described above, the liquid crystal panel 10 including the first substrate and the second substrate is seated through the panel guide 45, and the liquid crystal panel 10, the panel guide 45, and the backlight unit are They are coupled to each other by a lower cover bottom 50 and an upper case top 55 through a plurality of fastening means to constitute a liquid crystal display device.

Meanwhile, according to a recent trend in the display field, slimming of the liquid crystal display device and implementation of a narrow bezel are important, and in this case, it is inevitable to minimize the gap between the liquid crystal panel 10 and the backlight unit.

Accordingly, the liquid crystal panel 10 and the optical sheet 41 come into contact with each other under the vibration and transportation environment of the commercialized liquid crystal display device, and at this time, the static electricity remaining in the optical sheet 41 flows to the liquid crystal panel 10 ), which may cause static defects, in which stains are observed when observing images.

In addition, due to an increase in frictional force due to contact between the lower second polarizing plate 11 and the optical sheet 41 , a phenomenon in which the second polarizing plate 11 is cracked and a foreign substance due to the grinding may occur.

An object of the present invention is to provide a polarizing plate capable of improving foreign matter defects caused by static electricity and cracking of the polarizing plate, a method for manufacturing the same, and a liquid crystal display device having the same.

In addition, other objects and features of the present invention will be described in the following description of the invention and claims.

In order to achieve the above object, a polarizing plate according to an embodiment of the present invention includes a substrate; a protective layer formed on at least one side of the substrate; and an antistatic layer formed by adding a fluorine (F)-based polymer or an antistatic component to the outer surface of the protective layer.

In this case, the protective layer may be made of an acrylic polymer.

In this case, the antistatic layer may be made of a fluorine _{-based polymer of R: Si-F 3 .}

In this case, the antistatic layer may include an F-group formed on the outer surface of the protective layer.

The antistatic layer may include an inorganic silica filler or lubricant in addition to the fluorine-based polymer.

The antistatic component may include a conductive material made of a polymer or a metal.

A method of manufacturing a polarizing plate according to an embodiment of the present invention includes: providing a polarizing plate comprising a substrate, a protective layer formed on at least one side of the substrate, and a protective film attached to the outside of the protective layer with an adhesive interposed therebetween; and transferring the adhesive to the outside of the protective layer when removing the protective film from the polarizing plate, characterized in that the adhesive is subjected to a friction reduction treatment to include a fluorine-based polymer or an antistatic component.

In this case, the pressure-sensitive adhesive may be subjected to a friction reduction treatment to include a filler or lubricant of inorganic silica in addition to the fluorine-based polymer.

The pressure-sensitive adhesive may be subjected to a friction reduction treatment to include a conductive material made of a polymer or a metal as the antistatic component.

A liquid crystal display device according to an embodiment of the present invention includes a liquid crystal panel; and upper and lower polarizing plates attached to the upper and lower surfaces of the liquid crystal panel and comprising a substrate and a protective layer formed on at least one side of the substrate, wherein the lower polarizing plate is a fluorine-based polymer or antistatic component on the outer surface of the protective layer It is characterized in that it further comprises an antistatic layer formed by the addition.

As described above, the polarizing plate and its manufacturing method according to the present invention, and the liquid crystal display device having the same, reduce the distance between the liquid crystal panel and the backlight unit by performing a friction reduction treatment on the outer surface of the polarizing plate or in the adhesive of the protective film. It provides the effect of improving the foreign material defect caused by static electricity and cracking of the polarizing plate.

1A and 1B are exemplary views showing characteristics of light passing through a liquid crystal panel.
2 is a cross-sectional view schematically showing the structure of a general liquid crystal display device.
3A and 3B are an exploded perspective view and a cross-sectional view schematically showing components of a polarizing plate according to a first embodiment of the present invention;
4A and 4B are cross-sectional views and partially enlarged views schematically showing the structure of a polarizing plate according to a first embodiment of the present invention.
5 is a view showing a comparison of the friction force between the polarizing plate and the optical sheet.
6 is a table showing a comparison of cracking test results of polarizing plates.
7 is a table showing a comparison of vibration test results of a liquid crystal display.
8A and 8B are cross-sectional views schematically illustrating a part of a manufacturing process of a polarizing plate according to a second embodiment of the present invention.
9A and 9B are cross-sectional views schematically illustrating a part of a manufacturing process of a polarizing plate according to a third embodiment of the present invention.
10 is a cross-sectional view schematically showing the structure of an optical sheet according to the present invention.
11A and 11B are cross-sectional views schematically showing a part of a manufacturing process of another optical sheet according to the present invention.

Hereinafter, with reference to the accompanying drawings, a polarizing plate according to the present invention, a method for manufacturing the same, and a preferred embodiment of a liquid crystal display having the same will be described in detail so that those of ordinary skill in the art can easily implement the present invention. Explain.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be embodied in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout. The sizes and relative sizes of layers and regions in the drawings may be exaggerated for clarity of description.

Reference to an element or layer to another element or “on” or “on” includes not only directly on the other element or layer, but also with other layers or other elements interposed therebetween. do. On the other hand, reference to an element "directly on" or "directly on" indicates that there are no intervening elements or layers.

The spatially relative terms "below, beneath", "lower", "above", "upper", etc. are one element or component as shown in the drawings. and can be used to easily describe the correlation with other devices or components. The spatially relative terms should be understood as terms including different orientations of the device during use or operation in addition to the orientation shown in the drawings. For example, when an element shown in the figures is turned over, an element described as "beneath" or "beneath" another element may be placed "above" the other element. Accordingly, the exemplary term “below” may include both directions below and above.

The terminology used herein is for the purpose of describing the embodiments, and thus is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, "comprise" and/or "comprising" refers to the presence of one or more other components, steps, operations and/or elements mentioned. or addition is not excluded.

3A and 3B are exploded perspective views and cross-sectional views schematically illustrating components of a polarizing plate according to a first embodiment of the present invention.

At this time, FIG. 3B schematically shows a cross-section of the components of the polarizing plate according to the first embodiment of the present invention shown in FIG. 3A cut along the line I-I'.

Referring to the drawings, the polarizing plate 120 according to the first embodiment of the present invention may include a substrate 121 and protective layers 122a and 122b formed on both sides of the substrate 121 .

The polarizing plate 120 is a general polarizing element that transmits natural light having a vibrating plane in all directions of 360 degrees and transmits only light having a vibrating plane in a certain direction and absorbs the remaining light to obtain polarized light.

It is common to use an element that divides the polarization component into a polarization component perpendicular to the incident plane and a polarization component parallel to the incident plane using a polarizer having light absorption characteristics, and linearly polarized light and elliptically polarized light are obtained by the polarizer.

For this, it is possible to have uniform polarization and high polarization efficiency by selecting an appropriate material and processing it in the form of a film according to the purpose.

For example, a polyvinyl alcohol (PVA) film treated with iodine is used as the polarizing substrate 121, and has excellent transparency, UV absorption and durability as well as stability and abrasion resistance to dimensions or deformation. A triacetate cellulose (TAC) film may be used as the protective layers 122a and 122b for protecting the PVA film.

In addition, a release film 124a and a protective film 124b may be further attached to protect the substrate 121 and the protective layers 122a and 122b that are adhered to each other.

At this time, the release film 124a is attached to the outside of the first protective layer 122a until the polarizing plate 120 is attached to the final product, and the protective film 124b is the polarizing plate 120 is attached to the final product. It may be attached to the outside of the second protective layer 122b in order to prevent flaws on the surface of the polarizing plate 120 until it is attached to the polarizer 120 .

An adhesive 123a is attached between the release film 124a and the first protective layer 122a, and the final product is attached to the surface from which the release film 124a is removed. On the other hand, the pressure-sensitive adhesive 123b may not be formed on the second protective layer 122b to which the protective film 124b is attached.

In this way, the polarizing plate 120 has a polarization axis for changing the polarization characteristics of light, and is formed on both sides of the PVA film 121 and the PVA film 121 produced by stretching PVA that has absorbed iodine as a polarizer with strong tension. first and second TAC films 122a and 122b for protecting and supporting the PVA film 121, a protective film 124b formed on one side of the second TAC film 122b, and the first TAC film ( It consists of a release film 124a formed on one side of 122a) via an adhesive 123a.

Although not shown, as an example, such a polarizing plate 120 may be manufactured through the following process.

First, a raw material roll on which the PVA film 121, the first and second TAC films 122a and 122b, the release film 124a, and the protective film 124b are wound is prepared.

Thereafter, the raw material roll is washed in a washing tank and subjected to a pretreatment process of drying in a drying oven, and then the first and second TAC films 122a and 122b are laminated on both sides of the PVA film 121 .

Then, after stretching the PVA film 121 to form an intermediate roll, a protective film 124b is laminated on the surface of the second TAC film 122b, while a release film is formed on the surface of the first TAC film 122a. (124a) is laminated to form a polarizing plate roll.

After that, after cutting with a punch for each size in a cutting press, manufacturing is completed by inspection and packaging.

However, the present invention is not limited to the manufacturing process of the above-described polarizing plate.

The polarizing plate 120 having such a configuration is attached to the upper and lower surfaces of the liquid crystal panel, respectively, so that the surface from which the release film 124a is removed is attached.

In this case, a reinforced substrate for protecting the liquid crystal panel from external impact may be further provided on the upper polarizing plate 120 attached to the upper surface of the liquid crystal panel.

Here, the tempered substrate may be made of, for example, tempered glass having a thickness of about 3 mm to protect the liquid crystal panel inside from external impact. Such tempered glass is a glass strengthened by heating the molded plate glass to 500 ~ 600°C close to the softening temperature and quenching it with compressed cooling air to compressively deform the glass surface and tensilely deform the inside. Compared to ordinary glass, the bending strength is 3 to 5 times, the impact resistance is 3 to 8 times stronger, and the heat resistance is excellent.

The polarizing plate 120 according to the first embodiment of the present invention configured in this way is attached to the upper and lower surfaces of the liquid crystal panel. Although not shown, the liquid crystal panel according to the first embodiment of the present invention is largely a color filter substrate, an array substrate, and a column. It may be composed of a liquid crystal layer formed between the color filter substrate and the array substrate in a state where the cell gap is maintained by the spacer.

The color filter substrate includes a color filter composed of a plurality of sub-color filters and a black matrix (BM) that distinguishes between the sub-color filters and blocks light passing through the liquid crystal layer, and applies a voltage to the liquid crystal layer. It may be formed of a transparent common electrode to be applied.

The array substrate may include a plurality of gate lines and data lines arranged vertically and horizontally to define a plurality of pixel regions, a thin film transistor which is a switching element formed in an intersection region of the gate line and the data line, and a pixel electrode formed in the pixel region. have.

The thin film transistor may include a gate electrode connected to the gate line, a source electrode connected to the data line, and a drain electrode electrically connected to the pixel electrode. In addition, the thin film transistor may include an active layer that forms a conductive channel between the source electrode and the drain electrode by a gate voltage supplied to the gate electrode.

Such a liquid crystal panel is provided with a backlight unit on its rear surface to supply light. This is because the liquid crystal display itself does not have a light emitting element and thus requires a separate light source.

In this case, any one of a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp (EEFL), a hot cold fluorescent lamp (HCFL) fluorescent lamp, or a light emitting diode (LED) may be applied as the light source.

Meanwhile, as described above, the distance between the liquid crystal panel and the backlight unit is reduced due to the slimming of the liquid crystal display and the implementation of the inner bezel. Accordingly, the polarizing plate 120 according to the first embodiment of the present invention can improve the frictional force reduction treatment on its outer surface, thereby improving the static electricity and foreign material defects caused by cracking of the polarizing plate as the distance between the liquid crystal panel and the backlight unit is reduced. characterized by having

4A and 4B are cross-sectional views and partially enlarged views schematically showing the structure of a polarizing plate according to the first embodiment of the present invention.

In this case, in the polarizing plate according to the first embodiment of the present invention shown in FIG. 3B, FIGS. 4A and 4B show, for example, the structure of the polarizing plate in a state in which the release film and the protective film are removed.

4B is an enlarged view of a portion A of the polarizing plate according to the first embodiment of the present invention shown in FIG. 4A.

Referring to the drawings, the polarizing plate 120 according to the first embodiment of the present invention may include a substrate 121 and protective layers 122a and 122b formed on both sides of the substrate 121 as described above.

In addition, the polarizing plate 120 according to the first embodiment of the present invention has an antistatic layer (anti-static) in which a fluorine (F)-based polymer or an antistatic component is added to the outer surface of the second protective layer 122b from which the protective film is removed. static layer) 125 may be further included.

_{For example, when the antistatic layer 125 made of a fluorine-based polymer of R: Si-F 3} is formed on the outer surface of the second protective layer 122b made of an acrylic polymer, a friction force is applied to the outer surface of the second protective layer 122b. A reducing F-group can be formed.

This reaction can be expressed by the following chemical formula.

[Formula] -COO-CH ₃ + R: Si-F ₃ --> -COO-R: Si-F ₃

However, the present invention is not limited thereto, and may be applied as long as the exposed outer surface of the second protective layer 122b is subjected to a frictional force improvement treatment or an antistatic treatment.

For example, in order to improve frictional force, a filler such as inorganic silica or a lubricant may be added in addition to the above-described fluorine-based polymer.

In addition, a conductive material made of a polymer and a metal may be used to prevent static electricity.

With the formation of the antistatic layer 125 as described above, even when the liquid crystal panel and the optical sheet come into contact with each other under the vibration and transportation environment of the liquid crystal display, the transfer of static electricity remaining in the optical sheet to the liquid crystal panel can be prevented. Accordingly, it is possible to prevent electrostatic defects in which spots are observed during image observation.

In addition, as the frictional force due to contact between the polarizing plate 120 and the optical sheet is reduced due to the formation of an F-group on the outer surface of the second protective layer 122b, the phenomenon of grinding of the polarizing plate 120 and the generation of foreign substances due to grinding can be minimized.

5 is a view showing a comparison of frictional force between a polarizing plate and an optical sheet.

At this time, FIG. 5 shows the results of testing the respective frictional forces when the polarizing plate, the acrylic film, and the TAC film according to the first embodiment of the present invention are positioned on a diffuser sheet.

Referring to the drawings, in the case of the polarizing plate having the antistatic layer according to the first embodiment of the present invention, it can be seen that the frictional force is reduced by about 30 to 40% compared to the conventional acrylic film and TAC film.

6 is a table showing a comparison of cracking test results of polarizing plates.

At this time, FIG. 6 shows the cracking test results of the conventional polarizing plate (Comparative Example 1, Comparative Example 2, and Comparative Example 3) and the polarizing plate (Example) according to the first embodiment of the present invention.

For example, after fixing a polarizing plate to a moving device for a cracking test, an optical sheet such as a diffusion sheet is attached to a fixed device such as a stage.

Thereafter, while applying a certain load such as a weight to the top of the moving equipment and moving (eg, moving a load of 800 g at a speed of 100 mm/sec 10 times), it is checked whether the surface of the polarizing plate is cracked.

For reference, the number in parentheses shown in the table indicates the number of samples in which the number of evaluations occurred.

In addition, NG indicates a case in which the number of samples in which splitting has occurred exceeds 3, and OK indicates a case in which the number of samples in which splitting occurs does not exceed 3 and thus process application is possible.

Referring to the drawings, it can be seen that the polarizing plate according to the first embodiment of the present invention passed the cracking test for all loads of 1.7Kg, 2.5Kg, and 3.0Kg compared to the conventional polarizing plate.

And, after applying static electricity of 15KV to the surface of the optical sheet 10 times, contacting the liquid crystal panel to measure the static electricity retention time. Compared to the conventional polarizing plate, static electricity disappears in more than 60 seconds, in the first embodiment of the present invention. In the case of the following polarizing plate, it was found that static electricity disappeared in less than 30 seconds.

Such friction and friction tests and static electricity tests were performed on a single polarizing plate, and the vibration test results for a commercialized liquid crystal display are as follows.

7 is a table showing comparison of vibration test results of liquid crystal display devices.

At this time, FIG. 7 shows a static electricity and tear test of a liquid crystal display device having a conventional polarizing plate (Comparative Example 1 and Comparative Example 2) and a liquid crystal display device having a polarizing plate according to the first embodiment of the present invention (Example). showing the results.

For reference, the number in parentheses shown in the table indicates the number of samples in which static electricity or grinding defects occurred according to the number of evaluations.

Referring to the drawings, it can be seen that, in the case of the liquid crystal display including the polarizing plate according to the first embodiment of the present invention, there is no foreign matter defect due to static electricity and cracking of the polarizing plate, so that image defects are improved.

On the other hand, as described above, the present invention is not applied only to the case where friction reduction treatment is applied to the outer surface of the polarizing plate in order to improve the foreign matter defect caused by static electricity and cracking of the polarizing plate.

The present invention is applicable even when a friction reduction treatment is performed in the adhesive of the protective film, which will be described in detail through the following second embodiment of the present invention.

8A and 8B are cross-sectional views schematically illustrating a part of a manufacturing process of a polarizing plate according to a second embodiment of the present invention.

First, referring to FIG. 8A , the polarizing plate 220 according to the second embodiment of the present invention includes a substrate 221 and a substrate 221 substantially the same as the polarizing plate according to the first embodiment of the present invention. It may include protective layers 222a and 222b formed on both sides.

A protective film 224 is attached to the outside of the polarizing plate 220 , that is, to the outside of the second protective layer 222b to prevent damage to the surface of the polarizing plate 220 .

At this time, although not shown, a release film may be attached to the other outside of the polarizing plate 220 , that is, to the outside of the first protective layer 222a until the polarizing plate 220 is attached to the final product.

An adhesive 223 may be interposed between the protective film 224 and the second protective layer 222b, and the adhesive 223 is subjected to a friction reduction treatment to include a fluorine-based polymer or an antistatic component.

As described above, the pressure-sensitive adhesive 223 may include a filler such as inorganic silica or a lubricant in addition to the fluorine-based polymer.

In addition, the antistatic component may include a conductive material made of a polymer and a metal.

As shown in FIG. 8B , the pressure-sensitive adhesive 223 is transferred to the outer surface of the polarizing plate 220 in the process of removing the protective film 224 from the polarizing plate 220 according to the first embodiment of the present invention. and an antistatic layer 225 having substantially the same role as that of the present invention is formed.

At this time, the drawing shows the case in which the pressure-sensitive adhesive 223 is transferred to the outside of the second protective layer 222b of the polarizing plate 220 as an example, but the present invention is not limited thereto.

A portion of the pressure-sensitive adhesive 223 may be transferred to the outside of the second protective layer 222b of the polarizing plate 220 to form the antistatic layer 225 , while the remaining portion may remain on the protective film 224 .

9A and 9B are cross-sectional views schematically illustrating a part of a manufacturing process of a polarizing plate according to a third embodiment of the present invention.

In this case, FIGS. 9A and 9B show, for example, a case in which friction reduction treatment is performed not only on the outer surface of the polarizing plate but also on the pressure-sensitive adhesive of the protective film.

Referring to FIG. 9A , the polarizing plate 320 according to the third embodiment of the present invention has a substrate 321 and a substrate 321 substantially the same as the polarizing plates according to the first and second embodiments of the present invention described above. may include protective layers 322a and 322b formed on both sides of the .

In addition, the polarizing plate 320 according to the third embodiment of the present invention may further include a first antistatic layer 325a to which a fluorine-based polymer or an antistatic component is added to the outer surface of the second protective layer 322b.

In addition, a protective film 324 is attached to the outside of the first antistatic layer 325a to prevent damage to the surface of the polarizing plate 320 .

At this time, although not shown, a release film may be attached to the other outside of the polarizing plate 320 , that is, to the outside of the first protective layer 322a until the polarizing plate 320 is attached to the final product.

An adhesive 323 may be interposed between the protective film 324 and the first antistatic layer 325a, and the adhesive 323 is subjected to a friction reduction treatment to include a fluorine-based polymer or an antistatic component.

As described above, the first antistatic layer 325a and the pressure-sensitive adhesive 323 may include a filler such as inorganic silica or a lubricant in addition to the fluorine-based polymer.

In addition, the antistatic component may include a conductive material made of a polymer, a metal, or the like.

As shown in FIG. 9B, the adhesive 323 is transferred to the outer surface of the polarizing plate 320 in the process of removing the protective film 324 from the polarizing plate 320, and the first antistatic layer 325a and A second antistatic layer 325b having substantially the same role is formed.

At this time, although the figure shows, for example, that the pressure-sensitive adhesive 323 is transferred to the outside of the first antistatic layer 325a of the polarizing plate 320 , the present invention is not limited thereto.

A portion of the adhesive 323 may be transferred to the outside of the first antistatic layer 325a of the polarizing plate 320 to form the second antistatic layer 325b, while the remaining portion may remain on the protective film 324 .

On the other hand, this friction reduction treatment may be applied to the upper optical sheet in addition to the lower polarizing plate, which will be described in detail with reference to the following drawings.

10 is a cross-sectional view schematically showing the structure of an optical sheet according to the present invention.

Referring to FIG. 10 , the optical sheet 441 according to the present invention may further include an antistatic layer 425 to which a fluorine-based polymer or antistatic component is added to an outer surface thereof.

The optical sheet 441 may be a diffusion sheet positioned on the upper side.

The antistatic layer 425 may include a filler such as inorganic silica or a lubricant in addition to the fluorine-based polymer.

In addition, the antistatic component may include a conductive material made of a polymer and a metal.

11A and 11B are cross-sectional views schematically showing a part of a manufacturing process of another optical sheet according to the present invention.

First, referring to FIG. 11A , another optical sheet 541 according to the present invention has a protective film 524 attached to its outer surface to prevent flaws on the surface of the optical sheet 541 .

An adhesive 523 may be interposed between the protective film 524 and the optical sheet 541 , and the adhesive 523 is subjected to a friction reduction treatment to include a fluorine-based polymer or an antistatic component.

As described above, the pressure-sensitive adhesive 523 may include a filler such as inorganic silica or a lubricant in addition to the fluorine-based polymer.

In addition, the antistatic component may include a conductive material made of a polymer and a metal.

As shown in FIG. 11b, the adhesive 523 is transferred to the outer surface of the optical sheet 541 in the process of removing the protective film 524 from the optical sheet 541, and the antistatic layer as described above ( 525) is formed.

At this time, although the figure shows, for example, that the pressure-sensitive adhesive 523 is transferred to the outer surface of the optical sheet 541, the present invention is not limited thereto.

A portion of the pressure-sensitive adhesive 523 may be transferred to the outer surface of the optical sheet 541 to form the antistatic layer 525 , while the remaining portion may remain on the protective film 524 .

Although many matters are specifically described in the above description, these should be construed as examples of preferred embodiments rather than limiting the scope of the invention. Accordingly, the invention should not be defined by the described embodiments, but should be defined by the claims and equivalents to the claims.

120,220,320: polarizing plate 121,221,321: base material
122a, 222a, 322a, 122b, 222b, 322b: protective layer
123a,123b,223,323,523: adhesive 124a,124b,224,324,524: protective film
125,225,325a,325b,525: antistatic layer
441: optical sheet

Claims (16)

write;
a protective layer formed on at least one side of the substrate;
a first antistatic layer formed by adding a fluorine (F)-based polymer or an antistatic component to the outer surface of the protective layer;
a second antistatic layer transferred to the outer surface of the first antistatic layer and formed by adding a fluorine-based polymer or an antistatic component; and
and a protective film attached to the outside of the second antistatic layer,
The first antistatic layer is made of a fluorine-based polymer of R: Si-F 3 represented by the following formula on the outer surface of the protective layer, and the F-group is formed on the outer surface of the protective layer to reduce frictional force.
[Formula] -COO-CH ₃ + R: Si-F ₃ --> -COO-R: Si-F ₃ The polarizing plate according to claim 1, wherein the protective layer is made of an acrylic polymer. delete delete The polarizing plate according to claim 1, wherein the antistatic layer includes a filler or lubricant of inorganic silica in addition to the fluorine-based polymer. The polarizing plate according to claim 1, wherein the antistatic component comprises a conductive material made of a polymer or a metal. providing a polarizing plate comprising a substrate, a protective layer formed on at least one side of the substrate, and a protective film attached to the outside of the protective layer with an adhesive interposed therebetween; and
and transferring the pressure-sensitive adhesive to the outside of the protective layer when removing the protective film from the polarizing plate,
The pressure-sensitive adhesive is subjected to a friction reduction treatment to include a fluorine-based polymer or an antistatic component,
The polarizing plate is transferred to the outer surface of the first antistatic layer and the first antistatic layer formed by adding a fluorine (F)-based polymer or antistatic component to the outer surface of the protective layer, and a fluorine-based polymer or antistatic component is added a second antistatic layer formed thereon;
The first antistatic layer is made of a fluorine-based polymer of R: Si-F 3 represented by the following formula on the outer surface of the protective layer, and an F-group for reducing friction is formed on the outer surface of the protective layer. A method of manufacturing a polarizing plate.
[Formula] -COO-CH ₃ + R: Si-F ₃ --> -COO-R: Si-F ₃ The method of claim 7, wherein the pressure-sensitive adhesive is subjected to a friction reduction treatment to include a filler or lubricant of inorganic silica in addition to the fluorine-based polymer. The method of claim 7, wherein the pressure-sensitive adhesive is subjected to a friction reduction treatment to include a conductive material made of a polymer or a metal as the antistatic component. liquid crystal panel;
a backlight unit installed on the rear surface of the liquid crystal panel, the backlight unit including a lamp, a reflecting plate, a diffusion plate, and an optical sheet, and supplying light to the liquid crystal panel;
a first polarizing plate attached to the upper surface of the liquid crystal panel; and
a second polarizing plate attached to a lower surface of the liquid crystal panel between the liquid crystal panel and the backlight unit;
The second polarizing plate may include: a first antistatic layer formed by adding a fluorine-based polymer or an antistatic component to a substrate and a protective layer attached to the upper and lower surfaces of the substrate, and an outermost surface of the protective layer; and a second antistatic layer transferred to the outer surface of the first antistatic layer and formed by adding a fluorine-based polymer or an antistatic component,
The first antistatic layer is made of a fluorine-based polymer of R: Si-F 3 represented by the following formula on the outer surface of the protective layer, and an F-group for reducing friction is formed on the outer surface of the protective layer. liquid crystal display device.
[Formula] -COO-CH ₃ + R: Si-F ₃ --> -COO-R: Si-F ₃ 11. The method of claim 10,
The optical sheet, the liquid crystal display device, characterized in that it further comprises a second antistatic layer to which a fluorine-based polymer or an antistatic component is added to the outer surface. 12. The liquid crystal display device of claim 11, wherein the protective layer is made of an acrylic polymer. delete delete The liquid crystal display of claim 11 , wherein the antistatic layer comprises an inorganic silica filler or lubricant in addition to the fluorine-based polymer. The liquid crystal display device of claim 11 , wherein the antistatic component includes a conductive material made of a polymer or a metal.

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