KR20120063429A - Method of fabricating patterned retarder - Google Patents

Abstract

PURPOSE: A patterned retarder manufacturing method is provided to reduce manufacturing costs by simplifying a manufacturing process. CONSTITUTION: A transparent substrate(210) is exposed to polarized UV light. First and second regions are defined on the transparent substrate. The substrate has anisotropic properties using a thermal process. A retarder material layer(220) is formed on the substrate. The UV light polarized in a first direction is projected to the first region of the retarder material layer. The UV light polarized in a second direction is projected to the second region. An anisotropic property is manifested inside the retarder material layer. First and second phase patterns(222,224) are alternatively formed.

Description

Method of manufacturing a patterned retarder {Method of fabricating patterned retarder}

The present invention relates to a patterned retarder which is a component constituting a 3D display, and more particularly, to a method of manufacturing a patterned retarder that implements a simplified manufacturing process.

Recently, as the users' demand for a display device capable of realizing a 3D image with a three-dimensional image is increased, a display device capable of expressing a 3D image has been developed in response to this.

In general, stereoscopic images expressing 3D are made by the principle of stereo vision through two eyes, and use the parallax of two eyes, that is, binocular disparity that appears because the two eyes are about 65 mm apart. A 3D image display device capable of displaying a stereoscopic image has been proposed.

A typical 3D image display device includes a liquid crystal display device, a patterned retarder attached to an outer surface of the liquid crystal display device, and a liquid crystal display device through the patterned retarder. It consists of spectacles which selectively transmit the image which comes out.

In this case, the patterned retarder may have a different phase value for the left eye image and the right eye image of the 2D image from the liquid crystal display device, that is, the right circle polarization for the right eye image such that the left circle polarization for the left eye image, for example. In order to make the phase value different for the left eye image and the right eye image, a complicated manufacturing process is required.

1A to 1D are cross-sectional views of manufacturing steps of a conventional patterned retarder.

First, as shown in FIG. 1A, a coating material 90 having a property that polymer side chains (not shown) are arranged in one direction in response to a polymer material, for example, UV light, on a substrate 10 is used. By applying and curing, an optical alignment film 20 having a plurality of disordered polymer side chains is formed on the entire surface.

Subsequently, as shown in FIG. 1B, the substrate 10 is positioned inside the heat treatment apparatus 95 with respect to the substrate 10 on which the optical alignment layer 20 is formed, and the substrate 10 is heated for a few seconds to several minutes. By performing a drying process to remove the solvent and the like remaining in the optical alignment film 20.

Next, as shown in FIG. 1C, a first exposure mask 70 having a light transmitting area TA and a blocking area BA is positioned on the solvent-oriented optical alignment layer 20, and the first exposure mask 70 is positioned. The first polarized UV light is irradiated vertically on the entire surface of the substrate 10 from the upper part of the exposure mask 70 so that the first polarized UV light is selectively photo-oriented in a first direction. 1 to form an alignment region (21). That is, the first polarized UV light is irradiated to any one of the left eye image train and the right eye video train so that the polymer side chains (not shown) are arranged in the first direction, and the first polarized UV light is The portion of the alignment layer 20 of the unirradiated portion is such that the polymer side chains (not shown) are still arranged in a disordered state.

In this case, the selective alignment of the first polarized UV light causes the optical alignment layer 20 to have a first alignment region 21 and a polymer side chain (not shown) in which polymer side chains (not shown) are well aligned in a first direction. Is a disorderedly arranged non-oriented region.

Next, as shown in FIG. 1D, the optical alignment layer 20 having the first alignment region 21 oriented in the first direction has a blocking area BA with respect to the first alignment region 21. For the non-oriented region, the second exposure mask 72 having the transmissive area TA is positioned, and then the second polarized light is irradiated with UV light to correspond to the transmissive area TA of the second exposure mask 72. The second alignment region 23 is formed by aligning the polymer side chains provided on the surface of the optical alignment layer 20 in a second direction perpendicular to the first direction.

Subsequently, as described above, the liquid crystal layer is formed on the photoalignment film including the first non-second alignment region aligned in the first direction and the second direction perpendicular thereto, and the first and second UV light treatments are performed. And a patterned retarder having two phase patterns.

However, the patterned retarder manufactured as described above is subjected to a series of processes such as coating, drying, split exposure using two polarized UV light, liquid crystal layer coating, and UV curing and firing thereof. Since the manufacturing process is very complicated, it is a situation that leads to an increase in the manufacturing cost by such a complicated manufacturing.

Accordingly, an object of the present invention is to provide a manufacturing method of a patterned retarder which can reduce manufacturing costs by simplifying a manufacturing process.

In order to achieve the above object, a method of manufacturing a patterned retarder according to an embodiment of the present invention is performed after exposure to polarized UV light on a transparent substrate having first and second regions alternated with each other in a stripe type. Coating a retarder material, wherein the retarder material is formed by annealing to form a retarder material layer; Firstly irradiating UV light polarized in a first direction to the first region of the retarder material layer; Irradiating UV light polarized in a second direction perpendicular to the first direction to the second region of the retarder material layer; Heat-treating the substrate irradiated with the polarized UV light to form anisotropy in the retarder material layer irradiated with the polarized UV light to form first and second phase patterns alternately formed. Include.

At this time, the first step of irradiating the polarized UV light in the first direction to the first region of the retarder material layer is a transmission region corresponding to the first region over the retarder material layer does not correspond to the second region And firstly irradiating UV light polarized in the first direction after the first mask including the blocking region, and perpendicular to the second area of the retarder material layer. And irradiating the UV light polarized in the direction to the second layer after the second mask is disposed on the retarder material layer through a second mask having a transmissive area corresponding to the second area and a blocking area corresponding to the first area. It is characterized by the secondary irradiation of the UV light polarized in the direction.

In addition, the UV light polarized in the first and second directions has an energy density of 1 mJ / cm 2 to 500 mJ / cm 2 per unit area, and the wavelength of the UV light polarized in the first and second directions is 200 nm to 500 nm. .

In the method of manufacturing a patterned retarder according to another embodiment of the present invention, anisotropy is expressed by heat treatment after exposure to polarized UV light on a transparent substrate having first and second regions alternated with each other in a stripe type. Coating a retarder material to form a retarder material layer; Firstly irradiating UV light polarized in a first direction with a first energy density on the entire surface of the retarder material layer; Irradiating UV light polarized in a second direction perpendicular to the first direction and having a second energy density greater than the first energy density to the first region or the second region of the retarder material layer; ; Heat-treating the substrate irradiated with the polarized UV light to form anisotropy in the retarder material layer irradiated with the polarized UV light to form first and second phase patterns alternately formed. Include.

The UV light of claim 4, wherein the UV light is polarized in a second direction perpendicular to the first direction and having a second energy density greater than the first energy density in the first region or the second region of the retarder material layer. The step of irradiating the light secondly includes: a first mask having a blocking area corresponding to one of the first area and the second area above the retarder material layer and having a transmission area corresponding to the other area. Afterwards characterized in that the second irradiation of the polarized UV light in the second direction, the first energy density is 1mJ / ㎠ to 500mJ / ㎠, the second energy density is at least two times the first energy density The wavelength of the UV light polarized in the first and second directions is 200nm to 500nm.

In the method of manufacturing a patterned retarder according to another embodiment of the present invention, anisotropy is expressed by heat treatment after exposure to polarized UV light on a transparent substrate having first and second regions alternated with each other in a stripe type. Coating a retarder material to form a retarder material layer; Firstly irradiating UV light having a first energy density and polarized in a first direction in any one of the first region and the second region of the retarder material layer; Irradiating UV light polarized in a second direction perpendicular to the first direction and having a second energy density less than the first energy density on the entire surface of the retarder material layer; Heat-treating the substrate irradiated with the polarized UV light to form anisotropy in the retarder material layer irradiated with the polarized UV light to form first and second phase patterns alternately formed. Include.

At this time, the first step of irradiating the UV light polarized in the first direction with a first energy density in any one of the first region or the second region of the retarder material layer, the above retarder material layer In any one of the first region and the second region, the first region is irradiated with UV light polarized in the first direction after the first mask is provided with a blocking region in response to the other region. Wherein the first energy density is 2 mJ / cm 2 to 1000 mJ / cm 2, and the second energy density has a value of 1/2 or less of the first energy density, and is UV polarized in the first and second directions. The wavelength of light is characterized by 200 nm to 500 nm.

On the other hand, the material characterized in that the anisotropy is expressed by heat treatment after exposure to the polarized UV light, a homopolymer (homopolymer) form a photoreactive liquid crystal group is located in the side chain of the polymer, the photoreactive group and the liquid crystalline group carbon chain (carbon chain) connected to the form, or in the form of a copolymer (copolymer) in the form of a liquid crystal group additionally present in the side chain, or reactive mesogen (reactive mesogen) in the host polymer (host polymer) Or a liquid crystalline polymer is mixed to form a blended polymer.

In this case, a photoreactive liquid crystal group is positioned in the side chain of the polymer as a homopolymer, and a material having a form in which a photoreactive group and a liquid crystal group are connected by a carbon chain is a liquid crystal group. Or, the photoreactive group is characterized in that the form of a hydrogen bond is connected to form a liquid crystal group.

In addition, the homopolymer (homopolymer) type of material, the main chain is made of polymethacrylate, the side chain is characterized by consisting of a photoreactive liquid crystal polymer containing any one of azobenzene group, cinnamate group, coumarin group, benzylidenephthalimidine group.

And, the homopolymer (homopolymer) material is made of a photoreactive liquid crystalline polymer comprising a Cinnamate group, the photoreaction polymer has a homopolymer (homopolymer) form having a cinnamte group and a liquid crystalline group in the side chain, Copolymer having a cinnamate group in the side chain and forming a homopolymer showing liquid crystallinity through hydrogen bonding with adjacent side chains, or having a cinnmate group and a liquid crystal group in the side chain and at the same time an additional liquid crystal group. ) Is characterized by having a form.

On the other hand, the material characterized in that the anisotropy is expressed by heat treatment after exposure to the polarized UV light, the main chain (polymethacrylate), the side chain (side chain) is a photo reactive group (photo reactive group) Equipped with a mesogenic group (mesogenic group) at the same time, or in the form of a copolymer is characterized in that the form having a photoactive group and a liquid crystal (mesogenic group), respectively.

In addition, the litter material is characterized in that the refractive index anisotropy value Δn value is 0.10 to 0.18.

In addition, the retarder material layer is formed by spin coating or slit coating, wherein the retarder material layer is formed to a thickness of 0.5㎛ 2㎛, wherein the patterned retarder is the retardation value ( Δnd) in a range of 125 nm ± 10 nm for a wavelength of 550 nm.

In addition, the retarder material is a solid content concentration of 1% to 30% by weight, the solvent of the retarder material is one of ketones, ethers or a mixture of the ketones and ethers, the retarder The viscosity of the material is characterized by 1 mPas to 50 mPas.

In this case, the ketone is any one of cyclohexanone, cyclopentanone, cyclopetanone, MIBK (Methyl isobutyl ketone), and the ether is characterized in that PGME (Propylene glycol monomethyl ether) or Toluene.

In addition, the solvent further comprises a silicon-based or Acryl-based leveling agent (leveling agent) to improve the coating properties.

Before the first irradiation of the polarized UV light, the substrate on which the retarder material layer is formed is placed in or on a drying apparatus having a temperature atmosphere of room temperature (24 degrees) to 80 degrees, and maintained for 60 seconds to 300 seconds. It is a characteristic to advance the prebaking process to dry.

In addition, the heat treatment is a patterned retarder manufacturing method characterized in that the progress for 30 seconds to 10 minutes in a baking apparatus having a temperature atmosphere of 110 ℃ to 130 ℃.

The transparent substrate may be any one of a glass substrate, a film, and a flexible substrate. When the transparent substrate is the film, triacetate cellulose (TAC) cyclo olephine polymer (COP), polycarbonate (PC), and PMMA (poly) may be used. It is characterized by consisting of methyl methacrylate (PET), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polystyrene (PS), and polyimide (PI).

The method of manufacturing a patterned retarder according to the present invention does not require a photoalignment film, and thus, the application, drying, and curing processes of the photoalignment film can be omitted, thereby simplifying the process, and thus simplifying the manufacturing cost. There is an effect that can be reduced.

1A to 1D are cross-sectional views of manufacturing steps of a conventional patterned retarder.
2 is a diagram illustrating a 3D image realization system.
3A to 3D are cross-sectional views of manufacturing steps of a patterned retarder according to an embodiment of the present invention.
4 is a diagram showing the molecular structure of the retarder material used in the present invention
5 is a view showing a state change during irradiation and heat treatment of the linearly polarized light in the retarder material according to an embodiment of the present invention.
6A-6E illustrate chemical structures according to various examples of litter materials of the present invention.
7A to 7C are cross-sectional views of a manufacturing process showing a method of manufacturing a patterned retarder having first and second phase patterns that are sequentially repeated according to a first modification of the present invention.
8A to 8C are cross-sectional views of a manufacturing process showing a method of manufacturing a patterned retarder having first and second phase patterns sequentially repeated according to a second modification of the present invention.

Hereinafter, a method of manufacturing a patterned retarder according to the present invention and a 3D image realization system capable of realizing a 3D stereoscopic image using the same will be described in detail.

First, a 3D image realization system using a general liquid crystal display will be briefly described.

In general, the liquid crystal display device includes a liquid crystal layer interposed between the first and second electrodes facing each other, and the liquid crystal molecules of the liquid crystal layer by an electric field generated by applying a voltage to the first and second electrodes. The image is displayed by driving.

Liquid crystal molecules have polarization property and optical anisotropy. Polarization property means that when liquid crystal molecules are placed in an electric field, charges in the liquid crystal molecules are attracted to both sides of the liquid crystal molecules, and the direction of molecular arrangement changes according to the electric field. Refers to changing the path or polarization state of the emitted light differently according to the incident direction or the polarization state of the incident light due to the elongated structure of the liquid crystal molecules and the aforementioned molecular arrangement direction.

Accordingly, the liquid crystal layer may exhibit a difference in transmittance due to voltages applied to the first and second electrodes, and display the 2D image by changing the difference for each pixel.

Meanwhile, in order to display a 3D stereoscopic image using a liquid crystal display device displaying a 2D image, a stereoscopic image display, an autostereoscopic stereoscopic display, and a holographic display method using special glasses have been proposed, of which specialty The stereoscopic image display method using glasses is most often used.

The three-dimensional image display method using special glasses transmits light of different brightness in polarized glasses method using the vibration direction or rotation direction of polarized light, time-divided glasses method which alternately presents the left and right images while switching left and right. It can be divided into concentration difference method.

2 is a diagram illustrating a 3D image realization system using general special glasses.

As shown in the drawing, the 3D image realization system using the special glasses includes a liquid crystal display 110 displaying large 2D images, a patterned retarder 140 attached to an outer surface of the liquid crystal display 110, The glasses 145 may be configured to selectively transmit an image passing through the liquid crystal display device 110 through the patterned retarder 140.

First, the liquid crystal display 110 includes an array substrate 115, a color filter substrate 120, a liquid crystal layer (not shown) interposed between the two substrates 115 and 120, and the two substrates 115, 120. Although not shown in the drawings, the first and second polarizing plates 125 and 130 attached to the outer side surfaces of the first polarizing plate 125 include a backlight unit (not shown). In this case, the first and second polarizing plates 125 and 130 are configured such that their transmission axes perpendicularly cross each other.

On the other hand, the patterned retarder 140 provided on the outer surface of the second polarizing plate 130 attached to the outer surface of the color filter substrate 120 is located in the pixel area (P) located in the odd pixel line in the horizontal direction. ) And the light emitted from the pixel region P through the second polarizing plate 130 to the left circularly polarized state, and corresponding to the pixel region P located in the even-numbered pixel lines to be the right circularly polarized state. The birefringent material whose phase is internally changed so as to play a role in the patterning is alternately patterned to have different directionalities for each pixel region P line. As such, the patterned retarder 140 for allowing light to be left circularly or rightly polarized is characterized by expressing λ / 4 phase difference.

The optical axis of the patterned retarder 140 in which the phase difference of λ / 4 is generated is +45 degrees and -45 degrees with respect to the transmission axis of the second polarizing plate 130 provided in the liquid crystal display device 110, respectively. To achieve.

Therefore, after the liquid crystal display 110 passes through the patterned retarder 140 due to the configuration of the 3D image implementing system 101, the left circularly polarized state is obtained from the pixel region positioned in the odd pixel line. Light is emitted from the pixel area P positioned in the even-numbered pixel line, and light in a right circularly polarized state is emitted. In this case, the pixel area P in the odd-numbered pixel line of the liquid crystal display device 110 receives a left-eye image signal incident to the left eye of the user to the pixel region P in the even-numbered pixel line. In this regard, the right eye image signal incident to the right eye is applied to form a display device capable of realizing a 3D image.

On the other hand, the 3D image viewing glasses 145 forming a set with the liquid crystal display device 110 including the lambda / 4 patterned retarder 140 having the above-described configuration, the conventional glasses made of a transparent glass material Polarizing films 150a and 150b and a λ / 4 retardation film (not shown).

At this time, when wearing the glasses 145, the left eye lens 145a corresponding to the left eye of the user has a λ / 4 phase film (not shown) and a first polarizing film 150a which serve to convert circularly polarized light into linearly polarized light. The right eye lens 145b is attached with a λ / 4 phase film (not shown) and a second polarizing film 150b which serve to selectively change circularly polarized light into linearly polarized light.

Therefore, the user wears the 3D image glasses 145 having such a configuration, and the liquid crystal display 110 for displaying images having different circularly polarized states with different left and right eye image data applied alternately line by line. When viewing an image through the left eye image through the left eye lens 145a and the right eye image through the right eye lens 145b, the user can view a 3D image by combining these two images. It becomes possible.

In the 3D image realization system 101 having such a configuration, one of the most important components for enabling 3D image realization is the patterned retarder 140, and the patterned retarder 140 is used in the background art. As described above, since a very complicated manufacturing process is a factor that increases the price of the 3D image realization system, it is necessary to simplify the manufacturing method and to reduce the manufacturing cost.

Hereinafter, a method of manufacturing a patterned retarder according to the present invention, which simplifies the process, will be described in detail with reference to the accompanying drawings.

3A to 3D are cross-sectional views illustrating manufacturing steps of a patterned retarder according to an embodiment of the present invention.

First, as shown in FIG. 3A, a retarder material in a solution state is coated on a transparent insulating substrate 210 by using a spin coating apparatus or a slit coating apparatus, etc., to about 0.5 μm to 2 μm on the entire surface of the substrate 210. A retarder material layer 220 having a thickness of is formed. In this case, the transparent insulating substrate 210 may be, for example, a glass substrate, a film, a flexible substrate, and the film may be tri acetate cellulose (TAC) cyclo olephine polymer (COP), polycarbonate (PC), or poly (PMMA). It may be made of any one of methyl methacrylate (PET), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polystyrene (PS), and polyimide (PI).

On the other hand, the retarder material is shown in Figure 4 (representing the molecular structure of the retarder material used in the present invention) and Figure 5 (repolarized light in the retarder material according to an embodiment of the present invention during irradiation and heat treatment As shown in the state diagram), a photo-reactive liquid crystalline polymer is a photo-reactive liquid crystalline polymer, which is characterized by axis-selective photochemistry due to exposure to linearly polarized light and liquid crystallization due to heat treatment. It is characterized by anisotropy through the self-orientation phenomenon. The retarder material having these characteristics has a polymethacrylate main chain, and the side chain has a photoreactive group and a mesogenic group simultaneously or in copolymer form. It is characterized by forming a form having each (functional group).

In this case, a photo-isomerization or photo-dimerization phenomenon is used as a trigger to achieve anisotropy, and for this purpose, the side chain is made of any one of azobenzene, cinnamate, coumarin, benzylidenephthalimidine. It is characteristic.

Retarder material according to an embodiment of the present invention is characterized in that the value of the refractive index anisotropy value Δn is 0.10 to 0.18.

On the other hand, looking at the anisotropic formation mechanism (mechanism) of the retarder material according to an embodiment of the present invention having such a configuration, largely in the axial sorting reaction of the linear polarizing plate light and photoreactive liquid crystal group and the self-orientation reaction of the liquid crystal group by the thermal energy Is caused.

In more detail with respect to the retarder material according to an embodiment of the present invention, a photopolymerizable liquid crystal group is located in the side chain of the polymer as a homopolymer material, the photoreactive group and the liquid crystal group is a carbon chain It is connected by).

In this case, the photoreactive group itself may form a liquid crystalline group, or the photoreactive group may be connected in a hydrogen bond form to form a liquid crystalline group.

In addition, the retarder material may be in the form of a copolymer (copolymer) may form a form in which the liquid crystal group is additionally present in the side chain, and may also form a form in which a monomer (monomer) is mixed with the host polymer (host polymer). .

Various examples of the litter material according to the present invention are shown below, and the chemical structures are shown in FIGS. 6A to 6E.

6A to 6C each show a chemical structure showing an example of a homopolymer form, FIG. 6D shows a chemical structure showing an example of a copolymer form, and FIG. 6E shows a reactive mesogen (RM) in a host polymer. The chemical structure which showed this mixed form as an example is shown.

More specifically, the retarder material according to an embodiment of the present invention will be described.

The retarder material according to one embodiment of the present invention, in the form of a homopolymer, may be made of a photoreactive liquid crystalline polymer including an Azobenzene group as shown in FIG. 6A.

Looking at the chemical structure of the photoreactive liquid crystal polymer containing azobenzene group, the polymethacrylate main chain has an azobenzene group as a side chain, where the azobenezene group shows liquid crystallinity.

The retarder material according to another embodiment of the present invention may be made of a photoreactive liquid crystalline polymer including a Cinnamate group as shown in FIGS. 6B, 6C, and 6D as another homopolymer form. In this case, the photoreaction polymer may be configured in various ways, and in particular, may be divided into three types.

That is, as shown in Figure 6b, the photoreaction polymer is made of a homopolymer having a cinnamte group and a liquid crystalline group in the side chain, or as shown in Figure 6c, has a cinnamate group in the side chain and adjacent Heteropolymers (or homopolymers) having liquid crystallinity through side chains and hydrogen bonds, or heteropolymers having cinnmate and liquid crystalline groups in the side chain, and at the same time having additional liquid crystalline groups (or co-polymer).

Figure 6b shows an example of the chemical structure of a homopolymer having a cinnamate group and a liquid crystalline group in the side chain, in which case biphenyl is connected to the main chain by a spacer (for example carbon chain), biphenyl again It can be seen that the form connected with this cinnamate group.

In this case, a spacer may be additionally present between the biphenyl group and the cinnamate group, and a methoxy group may further exist at the end of the cinnamate group.

These detailed chemical structure changes can affect solubility in specific solvents, photo-reactivity associated with the efficiency of the photoreaction, and finally in-plane order. .

FIG. 6C illustrates an example of a homopolymer form having a cinnamate group in the side chain and exhibiting liquid crystallinity through hydrogen bonding with an adjacent side chain. As a form of the liquid crystal polymer, the end group of the side chain is hydrogen bond. It is characteristic that can be. Here, the hydrogen bond plays a very large role in the anisotropic formation mechanism, which allows the polymer to show liquid crystallinity through the hydrogen bond despite the absence of the biphenyl group.

On the other hand, these materials are predominantly isomerization reaction at low irradiation energy and dimerization reaction occurs as the irradiation energy increases.

After polarized UV irradiation, raising the temperature at the time of hardening fixation to a phase (Tni: nematic-isotropic) portion of the liquid crystal phase causes an orientation expansion (orientational amplification) reaction to maximize anisotropy formation. In addition, anisotropy can be formed through hydrogen bonding between molecules, which helps to form anisotropy.

FIG. 6D shows an example of a copolymer having a cinnmate group and a liquid crystalline group in the side chain and at the same time having an additional liquid crystalline group. In addition to such a structure, the photoreactive group and the liquid crystalline moieties may form a copolymer. have.

FIG. 6E illustrates a form in which a monomer is mixed with a host polymer as an example, wherein the monomer plays a role of lowering the polymer's Tni temperature or helping to form anisotropy. . In this case, the reactive mesogen (RM) may be made into a polymer to form a blended polymer of a host polymer and a liquid crystalline polymer.

On the other hand, looking at the properties of the retarder material having a variety of chemical structures described above, the retardation value (△ n ~ d) in the reference wavelength band (550nm) is about 125nm ± 10nm, when dissolved in a solvent to form a solution state Viscosity of about 1mPas to 50mPas, the solid content except the solvent is characterized in that 1% to 30% by weight.

In this case, the solvent of the retarder material may be Cyclohexanone, cyclopentanone, cyclopetanone, MIBK (Methyl isobutyl ketone) as an example of ketone, or PGME (Propylene glycol monomethyl ether) or Toluene as an ether, In some cases, two or more solvents described above may be mixed. At this time, the solvent may be additionally added to the silicon-based or Acryl-based leveling agent (leveling agent) to improve the coating properties.

Next, an example of a drying apparatus having a temperature atmosphere of room temperature (24 ° C.) 80 ° C. to 80 ° C. of the substrate 210 on which the retarder material layer 220 is formed may be an oven, a hot chamber, or a hot plate (not shown). The solvent contained in the retarder material layer 220 is removed by drying the substrate 210 by heating the substrate 210 by maintaining the substrate 210 for 60 seconds to 300 seconds. This series of processes is called a pre-baking process.

Next, as illustrated in FIG. 3B, the transmissive area TA having a stripe shape with respect to the retarder material layer 220 which has undergone the prebaking process through a drying apparatus, and alternately have a stripe shape. The first mask 290 including the blocking area BA having a shape is positioned parallel to the surface of the substrate 210.

Thereafter, the retarder material layer 220 corresponding to the transmission area TA of the first mask 290 is first irradiated with UV light polarized on the first mask 290 toward the substrate 210. It is exposed to UV light polarized in the first direction.

In this case, the energy density per unit area of the UV light polarized in the first direction irradiated to the prebaked retarder material layer 220 is 1mJ / ㎠ to 500mJ / ㎠, the wavelength is preferably 200nm to 500nm Do.

Meanwhile, the energy density per unit area of the polarized UV light becomes an important factor in determining the retardation value of the retarder material layer 220. In order to achieve a patterned retarder that serves to make a linearly polarized light into a left circularly or rightly polarized state used in a 3D image realization system, that is, to view 3D images through a 2D display liquid crystal display device. The preferred retardation value (Δnd) of the patterned retarder is about 125 nm ± 10 nm with respect to the wavelength of 550 nm which is a reference wavelength.

Therefore, in order to satisfy this, in the manufacture of the patterned retarder according to the present invention, the energy density per unit area is 1mJ / cm 2 to 500mJ / cm 2 and is characterized by irradiating polarized UV light having a wavelength of 200nm to 500nm.

For example, polarized UV light having an energy density per unit area of 8 mJ / cm 2, 20 mJ / cm 2, 40 mJ / cm 2, 60 mJ / cm 2, 80 mJ / cm 2, and 100 mJ / cm 2 is prebaked to the retarder material layer 220. When irradiated, the retardation value (△ nd) for the final 550nm wavelength after heat treatment was found to be 18.3nm, 53.5nm, 71.8nm, 92.5nm, 101.5nm, 130.2nm, respectively.

In this case, only in the case of irradiating polarized UV light having an energy density per unit area of 100 mJ / cm 2, the retardation value (Δnd) for the 550 nm wavelength on which the retarder material is a reference is 130.2 nm, which is the range required herein. It has a retardation value of, but it is measured only for one of the various retarder types of materials presented herein, and for other materials it is irradiated with polarized UV light having an energy density per unit area of 1 mJ / cm 2. The retardation value was found to be located in the range of about 125nm ± 10nm.

It has been described that the retardation value of the retarder material layer is preferably within a range of about 125 nm ± 10 nm, but more precisely, the range may be further changed by the retardation value of the glasses for viewing 3D images.

In general, polarized glasses required for 3D viewing have a center value of about 125 nm ± 10 nm of the retardation value, and a patterned retarder for suppressing crosstalk phenomenon between polarized glasses having such characteristics and a patterned litter The optimum value of the retardation value is 125 nm ± 10 nm, and the crosstalk is hardly generated when the retardation value of the polarized glasses and the patterned retarder has a predetermined difference within a range of 10%. Therefore, when reflecting this, the retardation value of the patterned retarder is preferably determined in the range of ± 10% of the retardation value of the polarizing glasses.

The patterned retarder is used not only in a 3D image realization system but also in other fields, and the patterned retarder used in these fields has a different retardation value? Nd.

Therefore, in this case, the energy density value per unit area of the polarized UV light may be freely changed in the range of 1 mJ / cm 2 to 500 mJ / cm 2.

As a result of this process, the retarder material layer 220 exposed to the UV light polarized in the first direction forms the first phase portion 221a.

Next, as shown in FIG. 3C, the first polarized UV light is irradiated through the first mask 290 of FIG. 3B, and thus, on the retarder material layer 220 having the first phase portion 221a. The first mask (290 of FIG. 3B) located at is removed.

Next, the retarder material layer 220 to which the first polarized UV light is irradiated on the second mask 292 having a configuration in which the stripe-type transmission area TA and the stripe-type blocking area BA are alternately formed. Position it at the top.

In this case, the second mask 292 may correspond to the blocking area BA corresponding to the first area 221a to which the polarized UV light is irradiated when the first polarized UV light is irradiated onto the retarder material layer 220. And the transmission area TA correspond to the second area not completely irradiated by the polarized UV light and irradiated with the first polarized UV light.

Thereafter, similarly to the method of irradiating the first polarized UV light, the second mask 292 has a wavelength of 200 nm to 500 nm, an energy density of 1 mJ / cm 2 to 500 mJ / cm 2, and a polarization direction of the first polarized UV light. Secondary polarized UV light having a second direction perpendicular to the first polarized UV light is irradiated to the retarder material layer 220. At this time, the secondary polarizing plate UV light preferably has the same energy density and the same wavelength band as the primary irradiated polarized UV light.

Next, as shown in Figure 3d, the substrate 210 having the retarder material layer 220 irradiated with the primary and secondary polarized UV light is a firing apparatus having a temperature atmosphere of 80 ℃ to 130 ℃ ( 296) For example, the retarder material layer 220 is fired by placing it in or on an oven, hot chamber, hot plate, and then exposed to a temperature atmosphere of 80 ° C to 130 ° C for 30 seconds to 10 minutes. The patterned retarder 201 is completed. The process of baking the retarder material layer 220 by using the baking apparatus 296 is called a post-baking process.

As a result of the post-baking process, the retardation material layer 220 has a state in which retardation is expressed in a direction perpendicular to a direction in which polarized UV light is irradiated.

That is, the retarder material layer 220 used in the manufacture of the patterned retarder 201 according to the present invention maintains isotropy until a state of being exposed to polarized UV light due to its characteristics, and post-irradiates the polarized UV light. As the baking process proceeds, it has anisotropic properties. The retarder material layer 220 has a first phase portion (221a in FIG. 3c) and a second phase portion (221b in FIG. 3c) therein by changing the irradiation direction of the primary and secondary polarized UV light due to this characteristic. The first and phase patterns 222 and the second phase patterns 224 are arranged to have anisotropic properties in different directions, respectively, so that linearly polarized light is left and right polarized.

As described above, the patterned retarder 201 manufactured by the manufacturing method according to the present invention is not required to form a separate optical alignment film.

Therefore, the process of coating, drying, and firing the photo-alignment material does not need to be carried out as compared with the conventional method of manufacturing the photolithography, which forms the photo-alignment layer, thereby simplifying the manufacturing process and thereby reducing the manufacturing cost.

Meanwhile, although not shown in the drawings, the patterned retarder 201 manufactured as described above is separated into unit patterned retarders to have a proper size by performing a cutting process of cutting using a laser beam irradiation apparatus (not shown). do.

In addition, the unit patterned retarder having an antireflection function may be completed by forming an antireflective coating film on the unit patterned retarder separated into appropriate sizes or by attaching an antireflective coating film.

Meanwhile, in the manufacturing method of the patterned retarder according to the embodiment of the present invention shown in FIGS. 3A to 3C, first and second phases are performed by performing first and second exposures having the same energy density using two masks. Forming a pattern is shown as an example, but may be variously modified.

7A to 7C are cross-sectional views illustrating a method of manufacturing a patterned retarder having first and second phase patterns that are sequentially repeated according to a first modification of the present invention.

First, as shown in FIG. 7A, as described above, the retarder material in a solution state is coated on the transparent insulating substrate 310 by using a spin coating apparatus or a slit coating apparatus, so that the front surface of the substrate 310 is 0.5. A retarder material layer 320 having a thickness of about 2 μm to about 2 μm is formed. In this case, the transparent insulating substrate 310 may be, for example, a glass substrate, a film, a flexible substrate, the film is tri acetate cellulose (TAC) cyclo olephine polymer (COP), polycarbonate (PC), PMMA (poly) It may be made of any one of methyl methacrylate (PET), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polystyrene (PS), and polyimide (PI).

Meanwhile, after the retarder material layer 320 is formed on the transparent insulating substrate 310, a prebaking process is performed to dry. At this time, since the prebaking process proceeds in the same manner as in the embodiment, a detailed description thereof will be omitted.

Next, as shown in FIG. 7B, the first energy density is 1 mJ / cm 2 to 500 mJ / in front of the retarder material layer 320 of FIG. 7A without a mask on the dried retarder material layer 320 of FIG. 7A. By irradiating the first polarized UV light having a wavelength range of 200 nm to 500 nm, the entire retarder material layer 320 (FIG. 7A) has a first phase layer 321 having a retardation value of 125 nm ± 10 nm. To achieve.

Next, as shown in FIG. 7C, the stripe-type transmission area TA and the stripe-type blocking area BA are alternated on the first phase layer 321 having a retardation value of 125 nm ± 10 nm. The first mask 390 is positioned.

Thereafter, the wavelength is 200 nm to 500 nm through the first mask 390, and the energy density per unit area is 2 mJ / cm 2 to 1000 mJ / cm 2, which is twice the energy density of the primary polarized UV light, and the polarization direction is By irradiating the first phase layer 321 with the second polarized UV light having a direction perpendicular to the first polarized UV light, the portion exposed only to the first polarized UV light is the first phase part 321a. A portion exposed to both the primary and secondary polarized UV light forms a second phase portion 321b.

In this case, the second polarized light is characterized in that it has an energy density of more than twice the first polarized UV light. That is, if the primary polarized UV light is irradiated at 100mJ / cm 2 The secondary polarized UV light is characterized in that the polarized UV light having an energy density of 200mJ / cm 2 or more.

Next, the first and second exposures are made in this manner, so that the post-baking process is performed on the patterned material layer 320 having the first and second phase portions 321a and 321b in the same manner as described in the embodiment. A patterned retarder having first and first phase patterns (not shown) can be completed.

When manufacturing the patterned retarder as in the first modification described above, a total of one mask is used, which has the advantage of reducing the number of masks compared to the embodiment.

Meanwhile, as a method of manufacturing a patterned retarder according to another modified example, FIGS. 8A to 8C (a method of manufacturing a patterned retarder having first and second phase patterns which are sequentially repeated according to the second modified example of the present invention) Referring to FIG. 8A, the substrate 410 is formed by coating a retarder material in a solution state on a transparent insulating substrate 410 through a spin coating apparatus or a slit coating apparatus, as shown in FIG. 8A. The retarder material layer 420 having a thickness of about 0.5 μm to 2 μm is formed on the entire surface. At this time, the transparent insulating substrate 410 may be, for example, a glass substrate, a film, a flexible substrate, the film is tri acetate cellulose (TAC) cyclo olephine polymer (COP), polycarbonate (PC), PMMA (poly) It may be made of any one of methyl methacrylate (PET), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polystyrene (PS), and polyimide (PI).

Meanwhile, after the retarder material layer 420 is formed on the transparent insulating substrate 410, the prebaking process is performed to dry.

Next, as shown in FIG. 8B, a first mask 490 having alternating stripe-type transmission regions TA and blocking regions BA is positioned on the retarder material layer 420. Retarder corresponding to the transmission area TA of the first mask 490 by firstly irradiating first polarized UV light having an energy density of 2 mJ / cm 2 to 1000 mJ / cm 2 and having a wavelength band of 200 nm to 500 nm. A portion of the material layer 420 forms a first phase portion 421a having a retardation value of 125 nm ± 10 nm.

Subsequently, as shown in FIG. 8C, the first polarized light having a second energy density smaller than the first energy density on the front surface without a mask for the retarder material layer 420 having the first phase portion 421a formed thereon. Part of the retarder material layer 420 which was not exposed to the first polarized UV light by irradiating polarized UV light having a polarization direction perpendicular to the UV light of the second phase part having a retardation value of 125 nm ± 10 nm. (421b). At this time, when exposing the second polarized UV light, the first phase portion 421a is polarized in the first direction by the first polarized UV light, and a retardation value of 125 nm ± 10 nm is maintained. The second energy density of the second polarized UV light is properly adjusted so that the second phase portion 421b can be formed. In this case, although the second energy density of the second polarized UV light is different for each material forming the retarder material layer 420, the first phase portion 421a of the first phase portion 421a formed by being exposed to the first polarized UV light is different. In order not to generate a change in the retardation value is characterized by having a value less than the first energy density of the first polarized UV light, and further stably suppress the change in the retardation value of the first phase portion 421a At the same time, in order to form the second phase portion 421b in a direction perpendicular to the first direction, the second energy density is preferably equal to or less than 1/2 of the first energy density.

Next, the patterned retarder having the first and first phase patterns (not shown) is subjected to a post-baking process on the retarder material layer 420 subjected to the first and second exposures in this manner in the same manner as in the embodiment. You can complete more.

In addition, the manufacturing method of the patterned retarder according to the second modified example also has an advantage of reducing the number of masks compared to the embodiment by using a total of one mask.

FIG. 9 is a polarization optical microscope photograph of a patterned retarder having a size of 32 ″ actually manufactured by a manufacturing method according to an exemplary embodiment of the present invention. FIG. 9 is a photograph taken after λ / 4 retardation film is placed on a patterned retarder. to be.

As shown, the patterned retarder manufactured according to the embodiment of the present invention has a first phase pattern which transmits only left circle (or right circle) polarized light and a right circle (or left circle) polarization opposite to the first phase pattern. It can be seen that only the transmitted light is alternately formed with a width of about 365 μm ± 5 μm in the form of clearly alternating second phase patterns.

201: patterned retarder 210: substrate
220: retarder material layer 222: first phase pattern
224: Second Phase Pattern 296: Firing Device

Claims (24)

Forming a retarder material layer by coating a retarder material, characterized in that anisotropy is expressed by heat treatment after exposure to polarized UV light on a transparent substrate defined first and second regions alternate with each other in a stripe type Steps;
Firstly irradiating UV light polarized in a first direction to the first region of the retarder material layer;
Irradiating UV light polarized in a second direction perpendicular to the first direction to the second region of the retarder material layer;
Heat-treating the substrate irradiated with the polarized UV light to form anisotropy in the retarder material layer irradiated with the polarized UV light to form first and second phase patterns alternately formed.
Patterned retarder manufacturing method comprising a.
The method of claim 1,
The first step of irradiating the first area of the retarder material layer with polarized UV light in a first direction may include a transmission area corresponding to the first area over the retarder material layer, and a blocking area corresponding to the second area. After the first mask is provided is characterized in that the first irradiation of the UV light polarized in the first direction,
The second step of irradiating the second area of the retarder material layer with the polarized UV light in a second direction perpendicular to the first direction may correspond to the second area over the retarder material layer. The method of manufacturing a patterned retarder, characterized in that the second region is irradiated with UV light polarized in the second direction after interposing a second mask having a blocking region corresponding to one region.
The method of claim 1,
The UV light polarized in the first and second directions has an energy density of 1 mJ / cm 2 to 500 mJ / cm 2, and the wavelength of the UV light polarized in the first and second directions is 200 nm to 500 nm. Retarder manufacturing method.
Forming a retarder material layer by coating a retarder material, characterized in that anisotropy is expressed by heat treatment after exposure to polarized UV light on a transparent substrate defined first and second regions alternate with each other in a stripe type Steps;
Firstly irradiating UV light polarized in a first direction with a first energy density on the entire surface of the retarder material layer;
Irradiating UV light polarized in a second direction perpendicular to the first direction and having a second energy density greater than the first energy density to the first region or the second region of the retarder material layer; ;
Heat-treating the substrate irradiated with the polarized UV light to form anisotropy in the retarder material layer irradiated with the polarized UV light to form first and second phase patterns alternately formed.
Patterned retarder manufacturing method comprising a.
The method of claim 4, wherein
Irradiating UV light polarized in a second direction perpendicular to the first direction and having a second energy density greater than the first energy density to the first region or the second region of the retarder material layer; And a polarized light in the second direction after interposing a first mask having a blocking area corresponding to the other area of the first area or the second area above the retarder material layer. A method for producing a patterned retarder, characterized by irradiating UV light secondly.
The method of claim 4, wherein
The first energy density is 1mJ / ㎠ to 500mJ / ㎠, the second energy density is more than twice the first energy density, the wavelength of the UV light polarized in the first and second directions is 200nm to 500nm Patterned retarder manufacturing method characterized in that.
Forming a retarder material layer by coating a retarder material, characterized in that anisotropy is expressed by heat treatment after exposure to polarized UV light on a transparent substrate defined first and second regions alternate with each other in a stripe type Steps;
Firstly irradiating UV light having a first energy density and polarized in a first direction in any one of the first region and the second region of the retarder material layer;
Irradiating UV light polarized in a second direction perpendicular to the first direction and having a second energy density less than the first energy density on the entire surface of the retarder material layer;
Heat-treating the substrate irradiated with the polarized UV light to form anisotropy in the retarder material layer irradiated with the polarized UV light to form first and second phase patterns alternately formed.
Patterned retarder manufacturing method comprising a.
The method of claim 7, wherein
Irradiating UV light polarized in a first direction with a first energy density in any one of the first region or the second region of the retarder material layer,
UV polarized in the first direction after the first mask having a blocking area corresponding to the other area of the first area or the second area above the retarder material layer through the other area. A method for producing a patterned retarder, characterized by firstly irradiating light.
The method of claim 7, wherein
The first energy density is 2mJ / ㎠ to 1000mJ / ㎠, the second energy density has a value of 1/2 or less of the first energy density, the wavelength of the UV light polarized in the first and second directions Method for producing a patterned retarder, characterized in that 200nm to 500nm.
The method according to any one of claims 1, 4, and 7,
The material characterized in that the anisotropy is expressed by heat treatment after exposure to the polarized UV light,
As a homopolymer form, a photoreactive liquid crystal group is located in the side chain of the polymer, and the photoreactive group and the liquid crystal group are connected by a carbon chain,
In the form of a copolymer (Copolymer) forms a form in which the liquid crystal group is additionally present in the side chain,
A method for producing a patterned retarder, characterized in that a reactive polymer such as a reactive mesogen or a liquid crystalline polymer is mixed with a host polymer to form a blended polymer.
11. The method of claim 10,
As the homopolymer form, a photoreactive liquid crystal group is positioned in a side chain of a polymer, and a material having a form in which the photoreactive group and the liquid crystal group are connected by a carbon chain,
The photoreactive group itself forms a liquid crystalline group,
Or the photoreactive group is connected in the form of hydrogen bond to form a form representing a liquid crystal group.
11. The method of claim 10,
The homopolymer-type material,
The main chain is made of polymethacrylate, the side chain is a method for producing a patterned retarder, characterized in that made of a photoreactive liquid crystalline polymer containing any one of azobenzene group, cinnamate group, coumarin group, benzylidenephthalimidine group.
11. The method of claim 10,
The homopolymer material is made of a photoreactive liquid crystalline polymer including a Cinnamate group,
The photoreactive polymer has a homopolymer form having a cinnamte group and a liquid crystalline group in the side chain,
Form a homopolymer having a cinnamate group in the side chain and exhibiting liquid crystallinity through hydrogen bonding with adjacent side chains,
A method for producing a patterned retarder, characterized in that it has a cinnmate group and a liquid crystalline group in the side chain, and at the same time has a copolymer form having an additional liquid crystalline group.
The method according to any one of claims 1, 4, and 7,
The material characterized in that the anisotropy is expressed by heat treatment after exposure to the polarized UV light,
The main chain is made of polymethacrylate, and the side chain has photo reactive groups and mesogenic groups at the same time,
Or a copolymer in the form of a patterned retarder, characterized in that the form having a photo reactive group and a liquid crystal group (mesogenic group), respectively.
The method according to any one of claims 1, 4, and 7,
And said litter material has a refractive index anisotropy value of? N of 0.10 to 0.18.
The method according to any one of claims 1, 4, and 7,
And the retarder material layer is formed by spin coating or slit coating.
17. The method of claim 16,
The retarder material layer is a patterned retarder manufacturing method characterized in that formed to a thickness of 0.5㎛ 2㎛.
The method of claim 17
The patterned retarder is a patterned retarder manufacturing method characterized in that the retardation value (Δnd) is formed to be in the range of 125nm ± 10nm for a wavelength of 550nm.
17. The method of claim 16,
The retarder material has a solid concentration of 1% to 30% by weight,
The solvent of the retarder material is one of ketones, ethers or a mixture of the ketones and ethers,
Wherein the viscosity of the retarder material is 1 mPas to 50 mPas.
The method of claim 19,
The ketones are any one of cyclohexanone, cyclopentanone, cyclopetanone, MIBK (Methyl isobutyl ketone),
The ether is a patterned retarder manufacturing method characterized in that PGME (Propylene glycol monomethyl ether) or Toluene.
The method of claim 19,
The solvent is a patterned retarder manufacturing method characterized in that it further comprises a silicon-based or Acryl-based leveling agent (leveling agent) to improve the coating properties.
17. The method of claim 16,
Before first irradiating the polarized UV light, the substrate on which the retarder material layer is formed is placed on or in a drying apparatus having a temperature atmosphere of room temperature (24 ° C) to 80 ° C, and maintained by drying for 60 seconds to 300 seconds. A method for producing a patterned retarder, characterized in that the prebaking process is performed.
The method according to any one of claims 1, 4, and 7,
The heat treatment is a patterned retarder manufacturing method characterized in that the proceeding for 30 seconds to 10 minutes in a baking apparatus having a temperature atmosphere of 110 ℃ to 130 ℃.
The method according to any one of claims 1, 4, and 7,
The transparent substrate is any one of a glass substrate, a film, a flexible substrate,
When the transparent substrate is the film, tri acetate cellulose (TAC) cyclo olephine polymer (COP), polycarbonate (PC), poly methyl methacrylate (PMMA), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyethersulfone (PES) ), PS (polystyrene), PI (poly imide) characterized in that the method of producing a patterned retarder.

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