KR101354373B1 - Manufacturing method of multilayer reflective polizer and device thereof - Google Patents

Abstract

The method of manufacturing a reflective polarizer according to the present invention comprises the steps of preparing a plurality of multi-layer composite streams having different average optical thicknesses by using a plurality of composite extrusion rollers and joining them in a molten state, so that a separate adhesive layer and / It is possible to reflect all the S waves in the visible light wavelength range without the need for the PBL. Also, since the skin layer is formed on at least one surface of the core layer in a molten state, the skin layer is not subjected to a separate adhesion step. This makes it possible to remarkably reduce the manufacturing cost and to maximize optical properties at a limited thickness.

Description

Manufacturing method and multilayer reflective polizer and device

The present invention relates to a method and apparatus for manufacturing a multilayer reflective polarizer, and more particularly, to a core layer including a plurality of groups having different average optical thicknesses within the core layer and not forming an adhesive layer between the groups, and integrally with the core layer. The present invention provides a method and apparatus for manufacturing a multilayer reflective polarizer including a formed skin layer.

Flat panel display technology is mainly composed of liquid crystal display (LCD), projection display, and plasma display (PDP), which have already secured a market in the TV field. In addition, field emission display (FED) and electroluminescence display (ELD) And it is expected to occupy the field according to each characteristic. Liquid crystal displays are currently being used in a wide range of applications such as notebook computers, personal computer monitors, liquid crystal TVs, automobiles, and aircrafts, accounting for 80% of the flat panel market, and booming demand for LCDs worldwide.

Conventional liquid crystal displays place a liquid crystal and an electrode matrix between a pair of light absorbing optical films. In liquid crystal displays, the liquid crystal portion has an optical state that changes accordingly by moving the liquid crystal portion by an electric field generated by applying a voltage to the two electrodes. This process displays an image by using a polarized light in a specific direction as a 'pixel' containing information. For this reason, liquid crystal displays include a front optical film and a rear optical film that induce polarization.

  The optical film used in such a liquid crystal display does not necessarily have a high utilization efficiency of light emitted from the backlight. This is because 50% or more of the light emitted from the backlight is absorbed by the back side optical film (absorption type polarizing film). Therefore, in order to improve the utilization efficiency of the backlight in the liquid crystal display, a reflection type polarizer is provided between the optical cavity and the liquid crystal assembly.

  1 is a view showing the optical principle of a conventional reflective polarizer. Specifically, the P polarized light from the optical cavity toward the liquid crystal assembly is transmitted through the reflective polarizer to the liquid crystal assembly. The S polarized light is reflected from the reflective polarizer into the optical cavity, Direction is reflected in a randomized state and is then transmitted to the reflective polarizer so that the S polarized light is converted into P polarized light that can pass through the polarizer of the liquid crystal assembly and is transmitted to the liquid crystal assembly after passing through the reflective polarizer.

The selective reflection of the S polarized light and the transmission of the P polarized light with respect to the incident light of the reflective polarizer are performed in such a manner that the refractive index of each optical layer in the state of alternately stacking the flat optical layer having the anisotropic refractive index and the flat optical layer having the isotropic refractive index The optical thickness of each of the optical layers in accordance with the difference and the elongation process of the laminated optical layer, and the change of the refractive index of the optical layer.

  That is, the light incident on the reflective polarizer repeats the reflection of the S polarized light and the transmission of the P polarized light while passing through each optical layer, and finally, only the P polarized light of the incident polarized light is transmitted to the liquid crystal assembly. On the other hand, as described above, the reflected S polarized light is reflected in the polarization state of the diffused reflection plane of the optical cavity in a randomized state and then transmitted to the reflective polarizer. As a result, it is possible to reduce the waste of power with loss of light generated from the light source.

 However, the conventional reflective polarizer has an optical thickness and a refractive index between the optical layers that can be optimized for selective reflection and transmission of incident polarization by alternately stacking isotropic optical layers and anisotropic optical layers having different refractive indices. Since it is manufactured to have, there was a problem that the manufacturing process of the reflective polarizer is complicated. In particular, since each optical layer of the reflective polarizer has a flat plate structure, the P polarized light and the S polarized light must be separated in accordance with a wide incident angle range of incident polarized light, so that the number of layers of the optical layer is excessively increased and the production cost exponentially There was an increasing problem. Further, there is a problem that optical performance is deteriorated due to optical loss due to the structure in which the number of layers of the optical layer is excessively formed.

2 is a cross-sectional view of a conventional multilayer reflective polarizer (DBEF). Specifically, in the multilayer reflective polarizer, the skin layers 9 and 10 are formed on both sides of the core layer 8. The core layer 8 is divided into four groups (1, 2, 3, 4), in which each of the isotropic layers and the anisotropic layers are alternately stacked to form approximately 200 layers. Separate adhesive layers 5, 6, and 7 are formed between the four groups 1, 2, 3, and 4 forming the core layer 8. In addition, since each group has a very thin thickness of about 200 layers, these groups often contain a protective layer (PBL) since individual groups can be damaged if they are individually pneumatically shipped. In this case, there is a problem that the thickness of the core layer becomes thick and the manufacturing cost rises. In addition, since the reflective polarizer included in the display panel is limited in the thickness of the core layer for slimming, if the adhesive layer is formed on the core layer and / or the skin layer, the core layer is reduced by the thickness thereof, There was no problem. Further, since the inside of the core layer and the core layer and the skin layer are bonded by the adhesive layer, there is a problem that when the external force is applied, the elapse of time elapses, or the storage place is poor, delamination occurs. In addition, not only the defect rate is excessively increased in the process of adhering the adhesive layer, but also the destructive interference to the light source occurs due to the formation of the adhesive layer.

Skin layers 9 and 10 are formed on both sides of the core layer 8 and separate adhesive layers 11 and 12 are formed between the core layer 8 and the skin layers 9 and 10 for bonding them. do. When the conventional skin layer of polycarbonate and PEN-coPEN are integrated with the alternately laminated core layer by co-extrusion, peeling may occur due to the compatibility member and the crystallization degree is about 15% There is a high risk of occurrence of birefringence. Accordingly, in order to apply the polycarbonate sheet of the non-smelting process, an adhesive layer has to be formed. As a result, the yield decreases due to external foreign matters and process defects due to the addition of the adhesive layer process. Generally, in producing a polycarbonate-free sheet of the skin layer, birefringence occurs due to uneven shear pressure due to the winding process, It is necessary to control the molecular structure of the polymer and speed control of the extrusion line in order to compensate for the deterioration of productivity.

The method of producing the conventional multilayer reflective polarizer described above will be briefly described. After four co-extruded groups having different average optical thicknesses forming the core layer are separately co-extruded, the four co-extruded four groups are stretched, And then the four layers are adhered with an adhesive to form a core layer. This is because the peeling phenomenon occurs when the core layer is stretched after bonding the adhesive. Thereafter, the skin layers are bonded to both sides of the core layer. As a result, in order to construct a multi-layer structure, a two-layer structure is folded to form a four-layer structure, and a group (209-layer) is formed through a process of forming a multi-layer structure in a continuous folding manner. It was difficult to form a group inside the multilayer. As a result, four groups having different average optical thicknesses have to be separately co-extruded and bonded.

Since the above-described process is intermittently performed, a remarkable increase in the manufacturing cost has been brought about. As a result, the cost of all the optical films included in the backlight unit is the most expensive. As a result, there has been a serious problem that liquid crystal displays other than the reflective polarizer are frequently released even when the decrease in luminance is reduced in terms of cost reduction.

Thus, there has been proposed a reflective polarizer in which a birefringent polymer stretched in the longitudinal direction is arranged in a substrate, not a multilayer reflective polarizer, and a polymer capable of achieving the function of the reflective polarizer is dispersed. 3 is a perspective view of a reflective polarizer 20 including a rod-shaped polymer, in which birefringent polymers 22 stretched in the longitudinal direction are arranged in one direction inside the base material 21. Fig. The birefringent interface between the base material 21 and the birefringent polymer 22 causes a light modulation effect to perform the function of the reflection type polarizer. However, as compared with the above-mentioned alternately stacked reflective polarizer, it is difficult to reflect light in the entire wavelength range of visible light, resulting in a problem that the light modulation efficiency is too low. Accordingly, in order to have a transmittance and a reflectance similar to those of the alternately stacked reflective polarizer, an excessively large number of birefringent polymers 22 must be disposed inside the substrate. Specifically, in order to have optical properties similar to those of the above-described laminate-type reflective polarizer in the substrate 21 having a width of 1580 mm and a height (thickness) of 400 μm or less when a horizontal 32-inch display panel is manufactured on the basis of the vertical cross section of the reflective polarizer, At least 100% of circular or elliptical birefringent polymer 22 having a cross-sectional diameter in the longitudinal direction of 0.1 to 0.3 탆 must be contained. In this case, not only the production cost is excessively increased but also the facilities are excessively complicated, There is a problem that it is difficult to produce the facility itself and thus it is difficult to commercialize it. Further, since it is difficult to make various optical thicknesses of the birefringent polymer 22 contained in the sheet, it is difficult to reflect light in the entire visible light region, and there is a problem that the physical properties are reduced.

In order to overcome this problem, a technical idea including a birefringent island-in-the-sea yarn has been proposed. FIG. 4 is a cross-sectional view of a birefringent island-in-the-sea yarn included in the substrate, and the birefringent island-in-the-sea yarn may generate a light modulation effect at an optical modulation interface between the inner and sea portions of the inner portion, and thus, a very large number such as the birefringent polymer described above. Optical properties can be achieved even if the island-in-the-sea yarns are not disposed. However, since the birefringent island-in-the-sea yarn is a fiber, problems of compatibility, ease of handling, and adhesion with a substrate which is a polymer have arisen. Furthermore, due to the circular shape, light scattering is induced, and thus the reflection polarization efficiency of the visible wavelength is reduced, and the polarization characteristic is lowered compared to the existing products, thereby limiting the luminance improvement. As the area is subdivided, the voids cause the optical leakage due to light leakage, that is, light loss. In addition, there is a problem that a limitation occurs in the reflection and polarization characteristics due to the limitation of the layer configuration due to the organization of tissue in the form of a fabric.

The present invention relates to a method and apparatus for manufacturing a multilayer reflective polarizer, and more particularly, to a method for manufacturing a multilayer reflective polarizer including a core layer formed of a plurality of groups having different average optical thicknesses and a skin layer formed simultaneously with the core layer. It is to provide a device.

In order to achieve the above object, the present invention provides a multilayer reflective polarizer comprising a multilayer reflective polarizer including a core layer in which first and second components are alternately stacked, and a skin layer formed on at least one surface of the core layer, (1) supplying a first component, a second component, and a skin layer component to the extruding portions, respectively; (2) repeating units of the first component and the second component form two or more multi-layered composite streams alternately stacked, and each of the multi-layer composite streams has a plurality of multi- Forming a plurality of multi-layer composite streams having different average optical thicknesses of the repeating units by injecting the first component and the second component transferred from the first and second components into a plurality of composite extrusion compartments; (3) laminating the two or more multilayered composites into one to form a core layer, and laminating the skin layer component transferred from the extruder to at least one surface of the core layer; And (4) inducing spreading of the core layer in which the skin layer is laminated in the flow control unit.

 According to a preferred embodiment of the present invention, the first component is selected from the group consisting of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), polycarbonate (PC) (PS), heat resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene ), Polyurethane (PU), polyimide (PI), polyvinyl chloride (PVC), styrene acrylonitrile blend (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal Phenol, epoxy (EP), urea (UF), melamine (MF), unsaturated polyester (UP), silicone (SI) and cycloolefin polymers.

According to another preferred embodiment of the present invention, the second component is selected from the group consisting of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), polycarbonate (PC), polycarbonate (PS), heat resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (PU), polyimide (PI), polyvinyl chloride (PVC), styrene acrylonitrile (SAN), ethylene vinyl acetate (EVA), polyamide (PA) (EP), urea (UF), melamine (MF), unsaturated polyesters (UP), silicon (SI) and cyclic olefin polymers may be used alone or in combination. More preferably, co- .

According to another preferred embodiment of the present invention, the skin layer component is formed of at least one selected from the group consisting of polyethylene terephthalate (PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat resistant polystyrene (PM), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide Polyvinyl chloride (PVC), styrene acrylonitrile blend (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melamine ), Unsaturated polyesters (UP), silicones (SI), and cycloolefin polymers.

According to another preferred embodiment of the present invention, the step (2) may form three or more, but preferably four or more multi-layer composite streams.

According to another preferred embodiment of the present invention, the plurality of composite extrusion mouthpieces may be integrated.

According to another preferred embodiment of the present invention, the composite extrusion head may be a slit type composite extrusion head.

According to another preferred embodiment of the present invention, the first component conveyed in the extrusion part between steps (1) and (2) may include a plurality of layers having a different ejection amount to have different average optical thicknesses And then discharged through the first pressurizing means into different composite extrusion ports, respectively.

According to another preferred embodiment of the present invention, the second component conveyed in the extrusion part between the step (1) and step (2) includes a plurality of components having different discharge amounts in order to have different average optical thicknesses 2 compression means, respectively, into different composite extrusion ports.

According to another preferred embodiment of the present invention, the plurality of composite extrusion orifices have diameters of the polymer supply paths on the separation plate on which the first component and the second component are supplied and distributed in order to produce a multi- Can be different.

According to another preferred embodiment of the present invention, the plurality of composite extrusion orifices include a number of layers of the polymer supply path on the holding distribution plate on which the first component and the second component are supplied and distributed in order to produce a multi- May be different.

According to another preferred embodiment of the present invention, the plurality of composite extrusion tools have a number of layers of at least 50, preferably at least 100, more preferably at least 200, and most preferably at least 50, More than 300 can be.

According to another preferred embodiment of the present invention, the plurality of composite extrusion / detaching mechanisms may have a number of layers of 400 or more.

According to another preferred embodiment of the present invention, the flow control unit may be a T-die or a coat-hanger die.

According to another preferred embodiment of the present invention, after the step (5), (6) cooling and smoothing the polarizer transferred from the flow control unit; (7) stretching the polarizers subjected to the smoothing step; And (8) heat setting the stretched polarizer.

According to another preferred embodiment of the present invention, the average optical thicknesses between the first component and / or the second component forming the different multilayer composite streams may be different from each other.

According to another preferred embodiment of the present invention, the optical thicknesses of the repeating units forming the same multi-layer composite stream may preferably be within 20%, more preferably within 15% of the average optical thickness.

According to another preferred embodiment of the present invention, the plurality of multi-layer composite streams may have an average optical thickness of 5% or more, preferably 10% or more.

According to still another preferred embodiment of the present invention, there is provided an apparatus for manufacturing a multilayer reflective polarizer comprising a core layer having a first component and a second component alternately laminated and a skin layer formed on at least one surface of the core layer. Three or more extruded portions into which the one component, the second component and the skin layer component are separately added; The repeating unit of the first component and the second component forms two or more multilayered composite flows in which the laminated units are alternately stacked, and each of the multilayer composite flows is transferred from the extruder to reflect the shear wave (S wave) of a desired wavelength. A spin block portion including a composite extrusion hole for inputting a first component and a second component to produce two or more multilayered composites having different average optical thicknesses of repeating units; A collection block unit for laminating two or more islands-in-sea composites conveyed from the spin block unit into one to form a core layer, and communicating with the extruder unit and laminating the skin layer component transferred from the extruder unit to at least one surface of the core layer; And a flow control unit for inducing spreading of the core layer in which the skin layer transferred from the collection block unit is laminated.

According to another preferred embodiment of the present invention, the composite extrusion hole may be a slit-type composite extrusion hole.

According to another preferred embodiment of the present invention, the composite extrusion outlet may be three or more, preferably four or more.

According to another preferred embodiment of the present invention, the plurality of complex extrusion holes may be integral.

According to another preferred embodiment of the present invention, in order for the first component conveyed from the extruder to have a different average optical thickness between the multi-layered composite flow, the spin block portion by discharging the first component conveyed from the extruded portion It may include a plurality of first pressurizing means having a different discharge amount supplied to the complex extrusion port.

According to another preferred embodiment of the present invention, in order for the second component conveyed from the extruder to have a different average optical thickness between the multi-layer composite flow, the spin block portion by discharging the first component conveyed from the extruded portion It may include a plurality of first pressurizing means having a different discharge amount supplied to the complex extrusion port.

According to another preferred embodiment of the present invention, the plurality of composite extrusion holes have a diameter or cross-sectional area or a thickness of a slit of a detention hole on a distribution plate to which the first component is supplied and distributed to produce different multi-layer composites. Can be different.

According to another preferred embodiment of the present invention, the plurality of complex extrusion holes are different in the number of layers of the detention holes on the detention distribution plate to which the first component and the second component are supplied and distributed in order to produce different multilayered composites. can do.

According to another preferred embodiment of the present invention, the plurality of complex extrusion holes are preferably 50 or more, more preferably 100 or more, even more preferably 200 or more layers of the detention hole of each compound extrusion hole. In the above, most preferably, 300 or more.

According to another preferred embodiment of the present invention, the flow control unit may be a T-die or a coat-hanger die.

The manufacturing method of the present invention requires a separate adhesive layer and / or a protective layer (PBL) in the core layer since a plurality of multi-layer composite streams having different average optical thicknesses are manufactured using a plurality of composite extrusion / It is possible to reflect all of the S waves in the visible light wavelength range. Also, since the skin layer is formed on at least one surface of the core layer in a molten state, the skin layer is not subjected to a separate adhesion step. This makes it possible to remarkably reduce the manufacturing cost and to maximize optical properties at a limited thickness.

1 is a schematic view for explaining the principle of a conventional reflective polarizer.
2 is a cross-sectional view of a currently used multi-layer reflective polarizer (DBEF).
3 is a perspective view of a reflection type polarizer including a bar-shaped polymer.
4 is a cross-sectional view showing a path of light incident on a birefringent chart used for a reflection type polarizer.
Fig. 5 is a perspective view of the claw distribution plates of the slit-type extrusion head which can be used in the present invention, Fig. 6 is a bottom view thereof, and Fig. 7 is a coupling diagram.
8 is a cross-sectional view of a multi-layer composite flow according to a preferred embodiment of the present invention.
9 is a schematic diagram including two first pressing means for forming two multi-layer composite streams according to a preferred embodiment of the present invention.
10 is a schematic diagram including two second pressurizing means for forming two multi-layer composite streams according to a preferred embodiment of the present invention.
Figure 11 is a schematic diagram showing the lamination of the multi-layered composites and skin layer according to an embodiment of the present invention.
Figure 12 is a cross-sectional view of a coat-hanger die in accordance with a preferred embodiment of the present invention, and Figure 13 is a side view.
14 is a cross-sectional view of a multilayer reflective polarizer in accordance with a preferred embodiment of the present invention.
15 is a cross-sectional view of a multilayer reflective polarizer according to another exemplary embodiment of the present invention.
16 is a cross-sectional view of a multilayer reflective polarizer according to another preferred embodiment of the present invention.
17 is a schematic diagram of an apparatus for manufacturing a multilayer reflective polarizer according to a preferred embodiment of the present invention.
18 is a schematic diagram of an apparatus for manufacturing a multilayer reflective polarizer according to another preferred embodiment of the present invention.
19 is a schematic diagram of an apparatus for manufacturing a multilayer reflective polarizer according to another preferred embodiment of the present invention.
20 is an exploded perspective view of a liquid crystal display device including the reflective polarizer of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail with reference to the accompanying drawings.

According to a preferred embodiment of the present invention, a method for manufacturing a multilayer reflective polarizer comprising a core layer having a first component and a second component alternately laminated and a skin layer formed on at least one surface of the core layer, (1) Supplying the first component, the second component and the skin layer component to the extruders, respectively, (2) forming two or more multi-layered composites in which the repeating units of the first component and the second component are alternately laminated; In order to reflect the shear wave (S wave) of a desired wavelength, the multilayered composite flows, in which the first component and the second component transferred from the extruder are put into a plurality of complex extrusion holes, the two having different average optical thicknesses of the repeating units. (3) forming the core layer by laminating the two or more multilayered composites into one, and laminating the skin layer component transferred from the extruder to at least one surface of the core layer; and 4) And a step of inducing spreading the laminated core layer the skin layer based on the flow control member.

First, in step (1), the first component, the second component, and the skin layer component are supplied to the extruding portions, respectively. The first component is a polymer dispersed in the second component forming the base material, and may be used without limitation as long as it is used in a reflective polarizer in which a conventional polymer is dispersed. Preferably, the first component is polyethylene naphthalate (PEN), copolyethylene Polymers such as phthalates (co-PEN), polyethylene terephthalate (PET), polycarbonate (PC), polycarbonate (PC) alloys, polystyrene (PS), heat resistant polystyrene (PS), polymethylmethacrylate (PB), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), polyvinyl chloride (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), unsaturated polyesters (SI) and cycloolefin polymers Number and may be more preferably PEN.

The second component forms a substrate and can be used without limitation as long as it is used as a material of a substrate in a reflective polarizer in which a polymer is dispersed. Preferably, the second component is selected from the group consisting of polyethylene naphthalate (PEN), co-polyethylene naphthalate ), Polyethylene terephthalate (PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat resistant polystyrene (PS), polymethylmethacrylate (PMMA), polybutylene terephthalate ), Polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), polyvinyl chloride (PVC), styrene acrylonitrile (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), unsaturated polyester (UP) The olefin polymer may be used singly or in combination Can be used and may be more preferably, dimethyl 2,6-naphthalenedicarboxylate, dimethyl terephthalate and ethylene glycol, Im chroman-hexane dimethanol (CHDM), such as the monomers are suitably polymerized co-PEN.

The skin layer component can be used without limitation as long as it is usually used in a reflective polarizer in which a polymer is dispersed. Preferably, the skin layer component may be a polyethylene terephthalate (PET), a polycarbonate (PC), a polycarbonate (PC) ), Heat resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane ), Polyimide (PI), polyvinyl chloride (PVC), styrene acrylonitrile blend (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM) (UF), melamine (MF), unsaturated polyesters (UP), silicon (SI) and cycloolefin polymers. The polycarbonate alloy is preferably made of a polycarbonate and a modified glycol polycyclohexylene dimethylene terephthalate (PCTG), more preferably a polycarbonate and a modified glycol polycyclohexane (PCTG) may be a polycarbonate alloy having a weight ratio of 5:95 to 95: 5. In the meantime, the skin layer of the present invention is preferably made of a material having a small change in refractive index in the spreading and stretching process, more preferably polycarbonate or polycarbonate glass.

Meanwhile, the first component, the second component, and the skin layer component may be separately supplied to the independent extrusion units. In this case, the extrusion unit may be composed of three or more. It is also included in the present invention to feed one extruded portion including a separate supply path and a distribution port so that the polymers do not mix. The extruder may be an extruder, which may further include a heating means or the like to convert the supplied polymers in the solid phase into a liquid phase.

Next, as step (2), two or more multi-layer composite streams in which the repeating units of the first component and the second component are alternately stacked are formed, and each of the multi-layer composite streams is formed so as to reflect a transverse wave , And the first component and the second component transferred from the extrusion unit are put into a plurality of compound extrusion compartments to form two or more multilayer composite streams having different average optical thicknesses of the repeating units.

5 to 7 are a perspective view, a bottom view, and a coupling view of the cage dividing plates of the slit type extrusion orifice usable in the present invention. FIG. 6 is a perspective view showing the coupling structure of the detent plates of the slit-type extrusion apparatus. FIG. The first receiving distribution plate S1 located at the upper end of the slit-shaped extrusion opening may be constituted by the first component supply path 50 and the second component supply path 51 in the interior thereof. So that the first component transferred through the extrusion portion can be supplied to the first component supply path 50 and the second component can be supplied to the second supply path 51. In some cases, a plurality of such supply paths may be formed. Polymers that have passed through the first receiving distribution plate S1 are transported to the second receiving distribution plate S2 located below. The first component introduced through the first component supply path 50 is branched and transferred to the plurality of first component supply paths 52 and 53 along the flow path. In addition, the second component injected through the second component supply path (51) is branched and transferred to the plurality of second component supply paths (54, 55, 56) along the flow path. The polymers that have passed through the second detention distribution plate S2 are transferred to the third detention distribution plate S3 located below.

The first component supplied through the first component supply paths 52 and 53 is connected to the first component supply paths 60, 61, 62, 63, 67, 68, 69, 70 along the flow path. Similarly, the second components injected through the second component supply paths 54, 55 and 56 are respectively connected to the second component supply paths 57, 58, 59, 64, 65, 66 , 71, 72 and 73 along the flow path. The first component introduced through the first component supply passages 60 and 67 of the first component supply passages formed in the third pickling distribution plate S3 is supplied to the first component supply passages 60 and 67, To the first flow path 74 of the first flow path 74. Likewise, the first component injected through the second component supply paths 57, 64 and 71 of the second component supply paths formed in the third pickling distribution plate S3 flows through the second component supply path 57, To the second one of the first and second flow paths (75). In this way, the first component transferred through the first component supply paths of the third holding distribution plate S3 is distributed to the odd-numbered flow paths 74, 76, 78, 80 of the fourth holding distribution board S4 And the second component transferred through the second component supply paths of the third component distribution plate S3 is transferred to the even flow channels 75, 77, 79 of the fourth component distribution plate S4. Whereby the first component and the second component can be alternately stacked. According to the above-described principle, it is possible to further include a detachable distribution plate (not shown) at the lower portion of the fourth detachable distribution plate S4, which is perpendicular to the flow direction of the fourth detachable distribution plate, It is obvious to those skilled in the art to extend the number of channels by the number of layers. On the other hand, the first component transferred through the odd-numbered flow paths 74, 76, 78, 80 of the fourth bundled distribution plate S4 is divided into the odd-numbered flow paths 81, And the second component transferred through the even-numbered flow paths 75, 77 and 79 of the fourth holding distribution plate S4 is transferred to the fifth holding distribution plate 82, 84, 86, 88, 90, 91, 92 of the first to fifth flow paths S5, S5. FIG. 6 is a bottom view of the slit-type push-pulling apparatus of FIG. 5, and the outlet of the fifth pick-up distributing plate S5 is formed integrally with a slit-type not separated by a hole type. Whereby the first component and the second component form respective layers. Therefore, the number of layers of the multilayer composite stream can be determined according to the number of slits in the fifth holding distribution board S5. The number of preferable layers may be 100 or more, more preferably 150 or more, more preferably 200 or more, and most preferably 300 or more. Thereafter, the multilayer composite flow is discharged through the discharge port 94 of the sixth holding distribution plate. 8 is a cross-sectional view of a multi-layer composite current flow, in which the first component 100, 102 and the second component 101, 103 are alternately laminated. In this case, one of the first component 100 and the deposited second component 101 can be defined as a repeating unit, and one compound stream includes a plurality of repeating units.

5 to 7 are illustrations of a cowling distribution plate that can be used in a slit-type extrusion apparatus according to the present invention. In order to manufacture a multi-layer composite stream in which a first component and a second component are alternately stacked, It is obvious that a person skilled in the art will appropriately design and use the number, structure, size and shape of the holding hole, the slit size of the fifth holding distribution plate, and the size of the discharge port. On the other hand, the diameter of the slits in the bottom view of the fifth housing distribution plate may be 0.17 to 0.6 mm, and the diameter of the discharge port may be 5 to 50 mm, but the present invention is not limited thereto. The diameter of the slit and the like are well known to those skilled in the art.

On the other hand, the plurality of multi-layer composite streams have different optical thicknesses, the number of repeating units, etc. of the repeating units of alternately stacked first and second components forming different multi-layer composite streams to cover different wavelength ranges of light, can do. For this purpose, the size of the spinneret, the thickness of the slit, the shape, or the number of layers may be different from each other in each multilayer extrusion opening. The reflection type polarizer, which is finally manufactured through the spreading and stretching processes, has a plurality of repeating units stacked therein to form one group, and each group can be set to have a different average optical thickness.

More specifically, the optical thickness means n (refractive index) x d (physical thickness). Therefore, if two multilayer composite streams are formed, the optical thickness is proportional to the physical thickness (d) if there is no difference in refractive index between the first and second components of the multi-layer composite stream. Therefore, by varying the average value of the physical thickness (d) of the repeating units of the first component and the second component contained in each of the multi-layer composite streams, it is possible to derive the difference in optical thickness between the multi-layer composite streams. For this purpose, the thickness of the slits included in the slit-type extrusion opening can be designed differently for each extrusion opening, thereby making it possible to produce multi-layer composite streams having different average optical thicknesses.

 On the other hand, in order to cover the entire visible light region, the average optical thickness of the multilayer composite flow must be determined so as to correspond to various light wavelengths. For example, in order to set the average optical thicknesses of the repeating units of the multi-layer composite stream such that three complex streams are formed and correspond to 450 nm, 550 nm and 650 nm of the wavelength range of each light, the average optical thickness May be at least 5% different, more preferably at least 10% different. This allows reflection of the S wave in the entire visible region. In this case, the thicknesses of the first component and the second component forming the same repeating unit may be the same.

 Also, the number, the cross-sectional area, the shape, the diameter of the slit, and the like of the spinneret holes may be the same or different in the slit-type extrusion nozzle forming one multilayer composite flow. Furthermore, the optical thickness of the repeating units forming the same multi-layer composite stream may have a deviation of preferably 20% or less, more preferably 15% or less, relative to the average optical thickness. For example, if the average optical thickness of the repeating units of the first multi-layer composite stream is 200 nm, the repeating units forming the same first multi-layer composite stream may have an optical thickness variation within about 20%. On the other hand, the wavelength of light and the optical thickness are defined by the following relational expression (1).

[Relationship 1]

λ = 4nd

Where? Is the wavelength of light (nm), n is the refractive index, d is the physical thickness (nm)

Therefore, when the optical thickness (nd) deviates, it is possible to cover not only the wavelength of the target light but also the wavelength range of the light including the target, thereby greatly improving uniform optical properties. Meanwhile, d denotes the thickness of one layer, and since the repeating unit is composed of two layers of the first component and the second component, if the physical thickness of the first component and the second component is the same, the repeating unit and the wavelength of light Can be defined according to relation 2 below.

[Relation 2]

? = 2 (n ₁ d ₁ + n ₂ d ₂ )

(Nm), n ₁ is refractive index of one layer, n ₂ is refractive index of two layers, d ₁ is physical thickness of one layer (nm), and d ₂ is physical thickness of two layers (nm).

 The deviation of the optical thickness described above can be attained through imparting a deviation to the number, the cross-sectional area, the shape, the diameter of the slit or the like of the fixing hole in one slit-type extrusion mouth, or naturally achieved through a fine pressure distribution in the spreading process or the like You can.

Therefore, the plurality of multi-layered composite streams of the present invention can cover the entire visible light region by setting the average optical thicknesses of the repeating units constituting the composite stream differently, It is possible to reflect an S wave in a wide wavelength range by giving a deviation. Furthermore, although FIGS. 5-7 illustrate the production of one multi-layer composite stream in one slit-type extrusion slot, sections are added to the inside of the slit-type extrusion slot to produce a plurality of multi-layer composite streams, Is also included in the scope of the present invention corresponding to the integral slit-type extrusion mouthpiece. In addition, the thickness of the slit included in the slit-type extrusion slot can be designed differently for each extrusion slot to produce multi-layer composite streams having different average optical thicknesses.

 According to another preferred embodiment of the present invention, the first component conveyed in the extrusion part between steps (1) and (2) may include a plurality of components having different ejection amounts to have different average optical thicknesses 1 pressing means, respectively, into different slit-type extrusion ports. Specifically, FIG. 9 is a schematic diagram including a first pressing means for forming two multi-layer composite streams, in which a first component transferred from an extrusion (not shown) passes through the plurality of first pressing means 130,131 And is separately supplied to each of the slit-shaped extrusion ports 132, 133 in each of the first pressurizing means 130, 131. In this case, the first pressurizing means 130 and 131 have different discharge amounts, and an area difference occurs. When the slits 132 and 133 have the same specifications (when the diameters of the slits are the same) The average optical thickness of the first multi-layer composite stream and the second multi-layer composite stream formed through the second multi-layer composite stream may be different.

To this end, the discharge amount of the first pressurizing means 130 and 131 may be preferably 1 to 100 kg / hr, but is not limited thereto.

On the other hand, one first pressing means feeds the first component to the two slit-type push-pull corners and the two multi-layer composite streams formed by the two slit-type push-pull cores are joined to form one multi-layer composite stream, It is also possible that a group is formed. In this case, the final reflection type polarizer may be formed of four groups through four first component pressing means and eight slit type extrusion / detaching mechanisms. It is also possible that one of the first pressing means transports the first component to three or more slit-shaped push-pull tabs.

According to another preferred embodiment of the present invention, the second component conveyed in the extrusion part between the step (1) and step (2) includes a plurality of components having different discharge amounts in order to have different average optical thicknesses Respectively, through the two pressing means. Specifically, FIG. 10 is a schematic diagram including two second pressing means for forming two multi-layer composite streams, wherein a second component transferred from an extrusion (not shown) And is separately supplied to each of the slit-shaped extrusion seats 142, 143 in each of the second pressurizing means 140, 141. At this time, the first pressurizing means 150 and 151 have different discharging amounts, and through which the slits 152 and 153 have the same specifications (when the shape diameters of the supply conduits, etc. are the same) Layer composite stream and the second component of the second multi-layer composite stream may have different average optical thicknesses. For this, the discharge amount of the second pressing means 150 and 151 may be preferably 1 to 100 kg / hr, but is not limited thereto.

On the other hand, one second pressurizing means feeds the second component to the two slit-type extrusion drills, and the two multi-layer composite streams formed in the two slit-type extrusion drums are joined to form one multi-layer composite stream, It is also possible that a group is formed. In this case, the final reflection type polarizer may be formed of four groups through four second component pressing means and eight slit-type extrusion / detaching units. It is also possible that one second pressing means transports the second component to three or more slit-shaped extrusion orifices.

In the next step (3), the two or more multilayered composites are laminated together to form a core layer, and the skin layer component transferred from the extruder is laminated on at least one surface of the core layer. Specifically, FIG. 11 is a schematic view showing a lamination portion of a multilayer composite stream. The core layer 165 is formed by laminating a plurality of multilayer composite streams 161, 162, 163, and 164 manufactured through respective slit-type extrusion holes. The skin layer component transferred from the extrusion unit is laminated on at least one surface 161 and 164 of the island-in-the-sea composites forming the core layer. On the other hand, when the lamination step is carried out in a separate place or using an integrated multi-layer extrusion mold, the multi-layer composites and the skin layer in a separate aggregated distribution plate including a flow path through which the skin layer component flows can be laminated as one. have. Of course, it is also possible to laminate the multilayer composites first and then separately. In addition, when the number of multi-layer composites is large, it is also possible to perform a multi-stage lamination in the form of laminating some multi-layer composites first and then laminating them in order to facilitate lamination.

Meanwhile, a separate preliminary spreading step may be further carried out between the steps (2) and (3) or between the steps (3) and (4) to facilitate the spreading of the repeating units described below.

Next, in step (4), the core layer in which the skin layer is laminated is induced in the flow control unit. Specifically, Figure 12 is a cross-sectional view of a coat-hanger die, which is one type of preferred flow control that may be applied to the present invention, and Figure 13 is a side view. The degree of spreading of the core layer can be appropriately adjusted to adjust the repeating unit to have an optical thickness suitable for reflecting light of a desired wavelength. This can be suitably designed in consideration of further reducing the optical thickness in the subsequent stretching process. Specifically, in FIG. 12, the core layer having the skin layer sandwiched therebetween is spread widely to the left and right in the coat-hanger die, so that the first component included therein also spreads to the left and right. In addition, as shown in the side view of FIG. 13, the coat hanger die is widely spread to the left and right but has a structure of shrinking up and down so that the skin layer purges horizontally in the laminated core layer and shrinks in the thickness direction. This is based on Pascal's principle, in which the fluid in the enclosure is guided to spread widely in the width direction by the principle that the pressure is transmitted to the fine portion by a certain pressure. Therefore, the outlet size is wider in the width direction than the die inlet size, and the thickness is reduced. This requires the use of the Pascal principle in which the molten liquid material can flow and shape controlled by pressure in a closed system, preferably a polymer flow rate and viscosity induction such that a flow of laminar flow of less than 2,500 Reynolds numbers is preferred. When the flow of the turbulent flow is 2,500 or more, the induction of the plate-like type becomes uneven, and there is a possibility that the optical characteristic is varied. The left and right die width of the outlet of the coat-hanger die may be between 800 and 2,500 mm and the fluid flow of the polymer is required to regulate the pressure so that the Reynolds number does not exceed 2,500. The reason is that the polymer flow becomes turbulent and the arrangement of the cores may be disturbed. Also, the internal temperature may be 265 to 310 ° C.

The flow control unit may be a T-die or a manifold type Coat-hanger die capable of inducing the spread of the repeating unit, but is not limited thereto, and may be used without limitation as long as it can induce spreading of the core layer.

The manufacturing method of the present invention requires a separate adhesive layer and / or a protective layer (PBL) in the core layer since a plurality of multi-layer composite streams having different average optical thicknesses are manufactured using a plurality of composite extrusion / It is possible to reflect all of the S waves in the visible light wavelength range. Also, since the skin layer is formed on at least one surface of the core layer in a molten state, the skin layer is not subjected to a separate adhesion step. This makes it possible to remarkably reduce the manufacturing cost and to maximize optical properties at a limited thickness.

According to a preferred embodiment of the present invention, after the step (4), (5) cooling and smoothing the polarizer induced by the spread transferred from the flow control unit, (6) stretching the polarizer after the smoothing step ; And (7) heat setting the stretched polarizer.

First, as a step (5), cooling and smoothing of the polarizer transferred from the flow control unit may be performed by cooling used in the manufacture of a conventional reflective polarizer to solidify it, and then may be performed through a casting roll process or the like.

Thereafter, a step of stretching the polarizer through the smoothing step is performed. The stretching may be performed through a conventional stretching process of a reflective polarizer, thereby causing a refractive index difference between the first component and the second component to cause a light modulation phenomenon at the interface, and the stretch- The optical thickness corresponding to the desired wavelength range is finally obtained. Therefore, in order to adjust the optical thickness of the repeating unit in the final reflective polarizer, it can be appropriately set in consideration of the slit diameter, spreading inducing condition, and stretching ratio of the slit-type extrusion / For this purpose, the uniaxial stretching or biaxial stretching can be preferably performed in the stretching step, and more preferably uniaxial stretching can be performed. In the case of uniaxial stretching, the stretching direction can be performed in the !!! direction. The stretching ratio may be 3 to 12 times. On the other hand, a method of changing an isotropic material to birefringent is commonly known. For example, when stretching under appropriate temperature conditions, polymer molecules may be oriented so that the material becomes birefringent.

Next, the final reflective polarizer may be manufactured by performing heat setting of the stretched polarizer as step (7). The thermal fixation may be heat-set through a conventional method, preferably at 180 to 200 ° C for 0.1 to 3 minutes through an IR heater.

On the other hand, in the present invention, when the average optical thickness of the target repeating unit between groups is determined, the reflection type polarizer of the present invention can be manufactured by properly controlling the slit size, the size of the flow control unit, and the stretching ratio .

The multilayer reflective polarizer of the present invention manufactured by the above-described method has a first layer having in-plane birefringence and a second layer alternately laminated with the first layer, in order to transmit the first polarized light irradiated from the outside and reflect the second polarized light. Wherein the first layer and the second layer have different refractive indices in at least one axial direction, the first layer and the second layer extend in at least one axial direction, and the first layer and the second layer Is a repeating unit, the repeating units form a group to reflect the shear wave (S wave) of the desired wavelength, the group is two or more, the groups are formed integrally, A core layer having a different average optical thickness and a skin layer integrally formed on at least one surface of the core layer may be included.

14 is a cross-sectional view of a multilayer reflective polarizer in accordance with a preferred embodiment of the present invention. Specifically, skin layers 189 and 190 are integrally formed on both sides of the core layer 180, and the core layer 180 is divided into two groups A and B. In the drawing, a dotted line dividing groups A and B means a virtual line. In the group A, the first layers 181 and 183 corresponding to the first component and the second layers 182 and 184 corresponding to the second component are alternately stacked. Herein, the first layer 181 and the second layer 182 are defined as one repeating unit (R1), and the group A may include at least 25 repeating units. Group B also alternately stacks the first layer (185, 187) and the second layer (182, 184) corresponding to the second component. Herein, the first layer 185 and the second layer 186 are defined as one repeating unit (R2), and the group A includes at least 25 repeating units, preferably 50 or more, more preferably 100 Or more, and most preferably 150 or more. The thicknesses of the first layer and the second layer may be the same.

On the other hand, the average optical thicknesses of the repeating units (R1) included in the group A and the average optical thicknesses of the repeating units (R2) included in the group B are different. This makes it possible to reflect different wavelengths of S waves. In addition, the optical thickness of the repeat units contained in group A may have an optical thickness variation preferably within 20%, more preferably within 15%, based on the average optical thickness of group A. Therefore, when the average optical thickness of the group A is 200 nm, it is possible to reflect a transverse wave (S wave) of a wavelength of 400 nm by the above-mentioned relational expression 2. [ In this case, if the thickness deviation is 20%, the wavelength band of about 320 to 480 nm can be covered. If the average optical thickness of the repeating units (R2) in the group B is 130 nm, the transverse wave (S wave) of 520 nm wavelength can be reflected by the relational expression 1. If the thickness deviation is 20%, the wavelength band of about 420 to 620 nm And in this case can be partially overlapped with the wavelength band of the group A, thereby maximizing the light modulation effect. In addition, since the first layer having the in-plane birefringence must transmit the P wave and reflect the S wave, the refractive index (n) can be set based on the thickness direction (refractive index of the z axis) through which the light passes and the average optical thickness can be calculated.

15 is a cross-sectional view of a multilayer reflective polarizer according to another exemplary embodiment of the present invention. 14, three groups (A, B, and C) having different average optical thicknesses are formed in the core layer, and the average optical thicknesses of the inter-group repeating units are different from each other.

16 is a cross-sectional view of a multilayer reflective polarizer according to another preferred embodiment of the present invention. Specifically, the core layer is formed of four groups, and each of the groups can be adjusted in the average optical thickness to cover the light wavelength band of 350 nm, 450 nm, 550 nm and 650 nm, respectively. In this case, the outer layer of the core layer is formed with groups having a large average optical thickness, and groups having a small average optical thickness in the inner layer can be formed. On the other hand, in order to cover the entire visible light region, the average optical thickness of the repeating units should be determined so as to correspond to various light wavelengths. To set the average optical thickness of the repeat units per group within the core layer to correspond to the optical wavelength band of 350 nm, 450 nm, 550 nm and 650 nm, the average optical thickness of the first component between the groups may be different by at least 5% , And more preferably 10% or more. This allows reflection of the S wave in the entire visible region.

On the other hand, they are integrally formed without an adhesive layer between the group and the group. And is also integrally formed between the core layer and the skin layer. Further, since the skin layer is produced simultaneously with the core layer and then the stretching process is performed, unlike the conventional adhesion of the core layer after stretching to the unstretched skin layer, the skin layer of the present invention can be stretched in at least one axial direction. As a result, the surface hardness is improved as compared with the non-drawn skin layer, and the scratch resistance is improved and the heat resistance can be improved.

According to a preferred embodiment of the present invention, a birefringence interface may be formed between the first layer and the second layer forming the core layer. Specifically, in the multilayer reflective polarizer in which the first layer and the second layer are alternately laminated, the substantial coincidence or incoincidence of the refractive index along the X, Y and Z axes in the space between the first and second layers is determined by the axis Which affects the degree of scattering of the polarized light beam. Generally, the scattering ability changes in proportion to the square of the refractive index mismatch. Thus, the greater the degree of discrepancy in refractive index along a particular axis, the more scattered light rays are polarized along that axis. Conversely, when the inconsistency along a particular axis is small, the polarized light rays along the axis are scattered to a lesser degree. If the refractive index of the second layer substantially coincides with the refractive index of the first layer along an axis, incident light polarized with an electric field parallel to this axis is not scattered regardless of the size, shape and density of the portion of the first layer Will pass through the first layer. Also, when the refractive index along the axis is substantially coincident, the light rays pass through the object without being substantially scattered. More specifically, the first polarized light (P wave) is transmitted without being influenced by the birefringent interface formed at the boundary between the second layer and the first layer, while the second polarized light (S wave) The light is affected by the birefringent interface formed at the boundary. As a result, the P wave is transmitted and the S wave is modulated by light such as scattering and reflection of light, resulting in separation of polarized light.

Therefore, the first layer and the second layer may form a birefringence interface at the cemented surface to cause a light modulation effect. Therefore, when the second layer is optically isotropic, the first layer may have birefringence. Specifically, when the refractive index in the x-axis direction is nX1, the refractive index in the y-axis direction is nY1, the refractive index in the z-axis direction is nZ1, and the refractive indexes of the second layer are nX2, nY2 and nZ2, Plane birefringence may occur. More preferably, the first layer and the second layer may differ in at least one of X, Y, and Z-axis refractive indexes, and more preferably, when the extension axis is the X-axis, Is 0.05 or less, and the difference in refractive index with respect to the X-axis can be 0.1 or more. On the other hand, when the difference in the refractive index is 0.05 or less, it is interpreted as matching.

Meanwhile, according to a preferred embodiment of the present invention, the total number of layers of the multilayer reflective polarizer may be 100 to 2000. The thickness range of the repeating unit can be appropriately designed according to the wavelength range of the desired light and the refractive index, and may preferably be 65 to 300 nm. The thicknesses of the first layer and the second layer forming the repeating unit may be the same or different. In the present invention, the core layer may have a thickness of 10 to 300 占 퐉 and the skin layer may have a thickness of 50 to 190 占 퐉, but the present invention is not limited thereto.

According to another preferred embodiment of the present invention, there is provided an apparatus for manufacturing a multilayer reflective polarizer including a core layer in which a first component and a second component are alternately stacked and a skin layer formed on at least one surface of the core layer, Three or more extruders into which the one component, the second component, and the skin layer component are separately introduced; Layered composite streams in which the repeating units of the first component and the second component are alternately laminated, and each of the multi-layer composite streams includes a plurality of multi-layer composite streams, A spin block including a composite extrusion nozzle for injecting a first component and a second component to produce two or more multi-layer composite streams having different average optical thicknesses of the repeating units; A collection block unit for laminating two or more islands-in-sea composites conveyed from the spin block unit into one to form a core layer, and communicating with the extruder unit and laminating the skin layer component transferred from the extruder unit to at least one surface of the core layer; And a flow control unit for inducing spreading of the core layer in which the skin layer transferred from the collection block unit is laminated.

17 is a schematic diagram of an apparatus for manufacturing a multilayer reflective polarizer in which a skin layer and a core layer are integrally formed in accordance with a preferred embodiment of the present invention. Specifically, the first extrusion part 220 into which the first component is injected, the second extrusion part 221 into which the second component is injected, and the third extrusion part 222 into which the skin layer component is injected. The first extrusion part 220 is connected to the spin block part C including the four slit type extrusion tools 223, 224, 225 and 226. At this time, the first extruder 220 supplies the first slit extruded holes 223, 224, 225, and 226 in a molten state. The second extruded portion 221 is also connected to the spin block portion C and supplies the second component to the four slit-shaped extrusion orifices 223, 224, 225, and 226 contained therein in a molten state. The four components of the multi-layer composite stream are alternately stacked with the first component and the second component through the four slit-type extrusion ports 223, 224, 225, and 226, and the average optical thicknesses of the repeating units are different. For this purpose, the respective slit diameters of the four slit-shaped extrusion ports may be different. The four slit-type pushing-in prongs 223, 224, 225, and 226 may be the slit-type pushing-out prongs shown in FIG. In addition, although four slit-type extrusion / detachment mechanisms have been described as an example, it is also within the scope of the present invention that a single slit-type extrusion / detachment mechanism can be used. Four multilayered composites manufactured through the four slit extruded holes 223, 224, 225, and 226 and the skin layer component transferred from the third extruded part 222 are combined into one in the collection block part 227. To form a skin layer formed on at least one surface of the core layer and the core layer. Therefore, the third extrusion part 222 and the collection block part 227 may be in communication with each other.

In this case, the collection block portion 227 may be formed separately, or in the case of using a single integrated slit-type extrusion mold, the multi-layered composites may be laminated in the form of a collection mold in the slit-type extrusion mold. 3, the extruder 222 may transfer the skin layer component to the collective detention through a separate flow path. The core layer and the skin layer laminated by the collection block unit 227 are transferred to the flow control unit 229 and the spread of the first component is induced to form a plate shape. Preferably, the flow control may be a T-die or a coat-hanger die.

18 is a schematic diagram of an apparatus for manufacturing a reflective polarizer in which a polymer is dispersed according to another exemplary embodiment of the present invention. 17, the first extrusion part 220 transfers the first component to the four first pressing means 233, 234, 235, and 236. The first pressurizing means 233, 234, 235 and 236 have different discharge amounts and discharge the first component into the plurality of slit-shaped extrusion ports 241, 242, 243 and 244. The second extruding portion 221 feeds the second component to the four second pressing means 237, 238, 239, 240. The second pressurizing means 237, 238, 239 and 240 have discharge amounts different from each other and discharge the second component to the plurality of slit-shaped extrusion ports 241, 242, 243 and 244. Four multi-layer composite streams having different average optical thicknesses are produced through four slit-type extrusion ports 241, 242, 243, and 244. The first pushing means, the second pushing means, and the plurality of slit-shaped pushing-out portions form a spin block portion (C).

19 is a schematic diagram of an apparatus for manufacturing a reflective polarizer in which a polymer is dispersed according to another exemplary embodiment of the present invention. 18, the present invention is characterized in that, in order to manufacture a multilayer reflective polarizer having four groups, eight slit-type extrusion / detaching units are used instead of four slit-type extrusion / detaching units, and multi-stage laminating is performed . Specifically, the first pressing means 233 discharges the first component to the two slit-shaped pushing-out portions 250, 251. The second pressing means 234 also discharges the first component to the two slit-shaped pushing-out portions 250, 251. The two slit-shaped extrusion ports 250 and 251 have the same average optical thickness between the multilayer composite streams since the first component and the second component are transported through the same first pressing means and second pressing means. In this way, eight multi-layer composite streams are formed and the two multi-layer composite streams have the same average optical thickness. The two multilayer composite flows having the same average optical thickness are respectively laminated at the first lamination portions 258, 259, 260, and 261 to form four multilayer composite flows, and the four multilayer composite flows and the skin layer component are formed. It is laminated by the two lamination portions 262 to form a core layer and a skin layer formed on at least one surface of the core layer.

Meanwhile, in FIG. 19, one first pressing means transfers the first component to the two slit-type extrusion molds, but it is apparent to those skilled in the art that the first component can be transferred to the two or more slit-type extrusion molds. The same may be applied to the second pressing means.

According to a preferred embodiment of the present invention, there is provided a liquid crystal display device including the reflective polarizer of the present invention. Specifically, FIG. 20 is an example of a liquid crystal display device employing a reflective polarizer of the present invention, in which a reflecting plate 280 is inserted into a frame 270, and a cold cathode fluorescent lamp 290 is disposed on an upper surface of the reflecting plate 280. Is located. An optical film 320 is disposed on the upper surface of the cold cathode fluorescent lamp 290. The optical film 320 includes a diffusion plate 321, a light diffusion film 322, a prism film 323, a reflection type polarizer 324 and the absorption polarizing film 325 are stacked in this order, but the order of lamination may be changed depending on the purpose, or a part of the constituent elements may be omitted or a plurality of them may be provided. For example, the diffusion plate 321, the light diffusion film 322, the prism film 323, and the like may be omitted from the overall configuration and may be changed in order or formed at different positions. Further, a phase difference film (not shown) or the like can also be inserted at an appropriate position in the liquid crystal display device. Meanwhile, the liquid crystal display panel 310 may be positioned on the upper surface of the optical film 320 by being inserted into the mold frame 300.

The light emitted from the cold cathode fluorescent lamp 290 reaches the diffuser plate 321 of the optical film 320. The light transmitted through the diffusion plate 321 passes through the light diffusion film 322 in order to advance the proceeding direction of the light perpendicularly to the optical film 320. The film having passed through the light diffusion film 322 reaches the reflection type polarizer 324 after passing through the prism film 323, thereby causing light modulation. Specifically, the P wave passes through the reflection type polarizer 324 without loss, but light modulation (reflection, scattering, refraction, etc.) occurs in the case of the S wave and is reflected again by the reflection plate 280, which is the back surface of the cold cathode fluorescent lamp 290 And the properties of the light are randomly changed into a P wave or an S wave, and then pass through the reflective polarizer 324 again. And then reaches the liquid crystal display panel 310 after passing through the absorption polarizing film 325. [ As a result, when the reflective polarizer of the present invention is inserted into a liquid crystal display device due to the above-described principle, remarkable improvement in luminance can be expected as compared with a general reflective polarizer. Meanwhile, the cold cathode fluorescent lamp 290 may be replaced with an LED.

In the present invention, the use of the reflective polarizer is described mainly with respect to the liquid crystal display, but the present invention is not limited thereto, and can be widely used in flat panel display technologies such as projection display, plasma display, field emission display and electroluminescence display.

Hereinafter, the present invention will be described in detail by Examples and Experimental Examples. The following Examples and Experimental Examples are merely illustrative of the present invention, and the scope of the present invention is not limited to the following Examples and Experimental Examples.

≪ Example 1 >

The process was performed as shown in FIG. 17. Specifically, a mixture of PEN having a refractive index of 1.65 as a first component and dimethyl terephthalate and dimethyl-2,6-naphthalene dicarboxylate as a second component in a molar ratio of 6: 4 was mixed with ethylene glycol (EG) and 1 : 2, a refractive index of 1.64 and a refractive index obtained by polymerizing 90 wt% of polycarbonate and 10 wt% of polycyclohexylene dimethylene terephthalate (PCTG) as a skin layer component 1.58 were injected into the first extruding portion, the second extruding portion and the third extruding portion, respectively. The extrusion temperature of the first component and the second component was 295 캜, and Cap. The polymer flow was calibrated through adjustment and the skin layer was subjected to an extrusion process at a temperature level of 280 占 폚.

Four composite flow types having different average optical thicknesses were prepared by using four slit-type extrusion nozzles of Figs. Specifically, the first component transferred from the first extruder is distributed to the four slit-type extrusion drills, and the second component transferred from the second extruder is transferred to the four slit-type extrusion drills. One slit-type extrusion slot is composed of 300 layers. The thickness of the slit of the first slit-type extrusion slot on the bottom surface of the fifth slotted distribution plate in Fig. 7 is 0.26 mm, the slit thickness of the second slit- , The slit thickness of the third slit-type extrusion nozzle was 0.17 mm, the slit thickness of the fourth slit-type extrusion nozzle was 0.30 mm, and the diameter of the discharge port of the sixth nozzle distribution plate was 15 mm 15 mm. Four multi-layer composite streams discharged through the four slit-type extrusion drums and

Skin layer components transferred through separate flow paths were laminated in a collection block and laminated into a single core layer and a skin layer integrally formed on both sides of the core layer. Spread was induced in the coat hanger die of FIGS. 12 and 13 to correct the flow rate and pressure gradient of the core layer polymer having the skin layer formed thereon. Specifically, the width of the die inlet is 200 mm, the thickness is 20 mm, the width of the die outlet is 960 mm, the thickness is 2.4 mm, and the flow rate is 1 m / min. Then, a smoothing process was performed on the cooling and casting rolls and stretched 6 times in the MD direction. Subsequently, heat setting was performed through an IR heater at 180 ° C. for 2 minutes to prepare a multilayer reflective polarizer as shown in FIG. 16. The refractive index (nx: 1.88, ny: 1.64, nz: 1.64) of the first component of the produced reflective polarizer was 1.64 and the refractive index of the second component was 1.64. Group A had 300 layers (150 repeating units), and the repeating unit had a thickness of 168 nm, an average optical thickness of 275.5 nm, and an optical thickness deviation of about 20%. Group B consisted of 300 layers (150 repeating units) with a thickness of 138nm, an average optical thickness of 226.3nm, and an optical thickness deviation of about 20%. Group C had 300 layers (150 repeating units) with a repeating unit thickness of 110 nm, an average optical thickness of 180.4 nm, and an optical thickness deviation of about 20%. The D group had 300 layers (150 repeating units), the thickness of the repeating unit was 200nm, the average optical thickness was 328nm, and the optical thickness deviation was about 20%. The core thickness of the manufactured multilayer reflective polarizer was 92.4 µm and the skin layer thickness was 153.8 µm, respectively, so that the total thickness was 400 µm.

<Example 2>

An 800-layer reflective polarizer was prepared in the same manner as in Example 1 except that the number of layers of the four slit-type extrusion holes was 200 each. The core layer thickness of the final product was 61.6 mu m and the skin layer thickness was 169.2 mu m, respectively, so that the total thickness was 400 mu m.

<Example 3>

A 600-layer reflective polarizer was prepared in the same manner as in Example 2 except that the third slit-type extrusion slot was not used.

&Lt; Comparative Example 1 &

The same procedure as in Example 2 was carried out except that the thickness of the slits of the four extruded slots was the same as that of the slits of the first slit-shaped bracket.

Comparative Example 2

In Example 1, four groups were individually formed into sheets through four slit extruded molds and drawn individually. Thereafter, four groups made of a sheet were adhered through a pressure sensitive adhesive to form a core layer, and then a skin layer was adhered to both surfaces of the core layer with a pressure sensitive adhesive to prepare an 800 layer reflective polarizer. The prepared polarizer has a thickness of 83.2 mu m in the core layer and 158.4 mu m in the thickness of the skin layer. The total thickness was 400 µm, and the pressure-sensitive adhesive layer was included in the thickness of the core layer and the skin layer.

<Experimental Example>

The following physical properties of the reflective polarizers prepared through Examples 1 to 3 and Comparative Examples 1 to 2 were evaluated, and the results are shown in Table 1 below.

1. Transmittance

Transmission axis transmittance and reflection axis transmittance were measured by ASTM D1003 method using COH300A analyzer of NIPPON DENSHOKU, Japan.

2. Polarization degree

The degree of polarization was measured using an OTSKA RETS-100 analyzer.

3. Relative luminance

In order to measure the brightness of the produced reflective polarizer, the following procedure was performed. The panel was assembled on a 32 "direct-type backlight unit equipped with a diffuser plate and a reflective polarizer, and the brightness was measured at nine points using a BM-7 meter of Topcon Co., and the average value was shown.

The relative luminance shows the relative values of the luminance of the other examples and comparative examples when the luminance of the reflective polarizer of Example 1 is 100 (reference).

Relative luminance (%) Polarization degree (λ = 550nm) Polarization degree (λ = 650nm) Polarization degree Transmission axis transmittance Reflective axis transmittance Polarization degree Transmission axis transmittance Reflective axis transmittance Example 1 100 93% 88% 3% 85.3% 88% 7% Example 2 97.2 89.4% 89% 5% 79.8% 89% 10% Example 3 94.2 85.5% 90% 7% 76.5% 90% 12% Comparative Example 1 84.8 73% 89% 14% 66.4% 89% 18% Comparative Example 2 92.7 85.3% 88% 7% 76% 88% 12%

As can be seen from Table 1, it can be confirmed that the reflective polarizers of Examples 1 to 3 of the present invention have significantly improved optical properties compared to the reflective polarizers of Comparative Examples 1 and 2. In addition, Comparative Example 2 including the adhesive layer is lower in optical properties than Example 2, which does not include the same number of adhesive layers. This is because deterioration in optical characteristics due to destructive interference with respect to the optical wavelength by the adhesive layer occurs.

Since the reflective polarizer of the present invention has excellent light modulation performance, it can be widely used in fields where optical modulation is required. Specifically, it can be widely used in flat panel display technologies such as a liquid crystal display device, a projection display, a plasma display, a field emission display, and an electroluminescence display which require high brightness such as a mobile display, an LCD and an LED.

Claims (39)

A core layer in which the first component and the second component are alternately laminated and remind A method for producing a multilayer reflective polarizer comprising a skin layer formed on at least one side of a core layer,
(1) supplying the first component, the second component, and the skin layer component to the extruding portions, respectively;
(2) forming two or more multilayered composites in which the repeating units of the first component and the second component are alternately laminated, wherein each of the multilayered composites reflects a shear wave (S wave) of a desired wavelength; Inputting the first component and the second component transferred from the plurality of composite extrusion holes having 50 or more layers of detention holes to form two or more multi-layered composite flows having different average optical thicknesses of the repeating units;
(3) laminating the two or more multilayered composites into one to form a core layer, and laminating the core layer and the skin layer at the same time by laminating the skin layer component transferred from the extruder on at least one surface of the core layer; And
(4) inducing the spread of the core layer in which the skin layer is laminated in the flow control unit. The method of claim 1, wherein the first component is according to claim 1, wherein the first component is polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), polycarbonate (PC ), Polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), Acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), polyvinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA) At least one selected from the group consisting of polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), unsaturated polyester (UP), silicone (SI) and cycloolefin polymer. Method for producing a multilayer reflective polarizer, characterized in that. The method of claim 1, wherein the second component of claim 1, wherein the first component is polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), polycarbonate (PC ), Polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), Acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), polyvinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA) At least one selected from the group consisting of polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), unsaturated polyester (UP), silicone (SI) and cycloolefin polymer. Method for producing a multilayer reflective polarizer, characterized in that. The method of claim 1, wherein the skin layer component of claim 1, wherein the first component is polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), polycarbonate (PC ), Polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), Acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), polyvinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA) At least one selected from the group consisting of polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), unsaturated polyester (UP), silicone (SI) and cycloolefin polymer. Method for producing a multilayer reflective polarizer, characterized in that. The method of claim 1,
Step (2) is a method of manufacturing a reflective polarizer, characterized in that to form three or more multi-layer composites. The method of claim 1,
Step (2) is a method for producing a reflective polarizer, characterized in that to form four or more multi-layer composites. The method of claim 1, wherein the plurality of composite extrusion holes are integrated. The method of claim 1,
The complex extrusion hole is a multilayer reflective polarizer manufacturing method, characterized in that the slit-type composite extrusion hole. The method of claim 1, wherein the step (1) and (2)
The first component conveyed from the extruder further comprises the step of ejecting to each of the different composite extrusion port through a plurality of first pressing means having a different discharge amount in order to have a different average optical thickness between the multi-layer composite flow Reflective polarizer manufacturing method. The method of claim 1, wherein the step (1) and (2)
The second component conveyed from the extruded part is discharged into different composite extrusion holes through a plurality of second pressing means having a different discharge amount in order to have a different average optical thickness between the multi-layer composite flows.  9. The multilayer according to claim 8, wherein the plurality of slit-type extrusion molds have different diameters of slits on the mold distribution plate to which the first component and the second component are supplied and distributed to produce different multilayer composites. Reflective polarizer manufacturing method. The method of claim 1, wherein the plurality of composite extrusion holes are characterized in that the number of layers of the polymer supply passage on the detention distribution plate to which the first component and the second component are supplied and distributed to produce different multi-layer composites Method of manufacturing a multilayer reflective polarizer. delete The method of claim 1,
The method of manufacturing a multilayer reflective polarizer, wherein the plurality of complex extrusion holes have a number of layers of detention holes of 100 or more. The method of claim 1,
The plurality of complex extrusion holes are a multilayer reflective polarizer manufacturing method, characterized in that the number of layers of the detention hole is 200 or more. The method of claim 1,
And said plurality of complex extrusion holes have a number of layers of the detention holes of each compound extrusion hole being 300 or more. The method of claim 1, wherein the flow control part is a T-die. The method of claim 1, wherein the flow control part is a coat-hanger die. The method of claim 1, wherein after step (4),
(5) cooling and smoothing the polarizer transferred from the flow control unit
(6) stretching the polarizers subjected to the smoothing step; And
(7) a method of manufacturing a multilayer reflective polarizer, comprising the step of heat setting the stretched polarizer. The method of manufacturing a multilayer reflective polarizer according to claim 1, wherein the average optical thicknesses of the first components forming different multilayer composites are different from each other. The method of claim 1, wherein the optical thicknesses of repeating units forming the same multilayered composite have a variation within 20% of the average optical thickness. The method of claim 1, wherein the optical thicknesses of repeating units forming the same multilayered composite have a variation within 15% of the average optical thickness. The method of claim 1, wherein the plurality of multilayer composites have an average optical thickness of at least 5%. The method of claim 1, wherein the plurality of multilayer composites have an average optical thickness of 10% or more. A core layer in which the first component and the second component are alternately laminated and remind An apparatus for manufacturing a multilayer reflective polarizer comprising a skin layer formed on at least one surface of a core layer,
Three or more extrusion parts into which the first component, the second component, and the skin layer component are separately added;
The repeating unit of the first component and the second component forms two or more multilayered composite flows in which the laminated units are alternately stacked, and each of the multilayer composite flows is transferred from the extruder to reflect the shear wave (S wave) of a desired wavelength. A spin block unit including a plurality of complex extrusion holes having 50 or more layers of detention holes for preparing two or more multilayered composites having different average optical thicknesses of repeating units by inputting the first component and the second component;
A collection block unit for laminating the two or more multi-layered composites transferred from the spin block unit to one to form a core layer and communicating with the extruder to bond the skin layer component transferred from the extruder to at least one surface of the core layer; And
Apparatus for manufacturing a multi-layer reflective polarizer including a flow control unit for inducing the spread of the core layer laminated the skin layer transferred from the collection block unit. 27. The apparatus of claim 25, wherein the composite extrusion hole is a slit-type composite extrusion hole. 27. The apparatus of claim 25, wherein the composite extrusion hole is three or more. 26. The apparatus of claim 25, wherein the composite extrusion hole is four or more in number. 26. The method of claim 25,
The plurality of composite extrusion port is a multi-layer reflective polarizer manufacturing apparatus characterized in that the integral. 27. The method of claim 25, wherein the spin block portion to discharge the first component conveyed from the extrusion unit to supply to the composite extrusion port in order to have a different average optical thickness between the multi-layered composite flow to the first component conveyed from the extrusion unit An apparatus for manufacturing a multilayer reflective polarizer comprising a plurality of first pressing means having different discharge amounts. The spin block part according to claim 25, wherein the spin block part discharges the first component conveyed from the extruded part and supplies it to the composite extrusion hole so that the second component conveyed from the extruded part has a different average optical thickness between the multilayer composite streams. An apparatus for manufacturing a multilayer reflective polarizer comprising a plurality of first pressing means having different discharge amounts. 26. The multilayer according to claim 25, wherein the plurality of slit-shaped extrusion blocks have different diameters of slits on the distribution plate to which the first component and the second component are supplied and distributed to produce different multilayer composites. Apparatus for manufacturing reflective polarizer. 27. The method of claim 25, wherein the plurality of complex extrusion holes are multi-layered reflection, characterized in that the number of layers of the detention hole on the detention distribution plate to which the first component and the second component are supplied and distributed to produce different multi-layer composites Apparatus for manufacturing polarizer. delete 26. The method of claim 25,
And said plurality of complex extrusion holes have a number of layers of the detention holes of each compound extrusion hole being 100 or more. 26. The method of claim 25,
And said plurality of complex extrusion holes have a number of layers of the detention holes of each compound extrusion hole being 200 or more. 26. The method of claim 25,
And said plurality of complex extrusion holes have a number of layers of the detention holes of each compound extrusion hole being 300 or more. The apparatus of claim 25, wherein the flow control part is a T-die. 27. The apparatus of claim 25, wherein the flow control unit is a coat-hanger die.

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