JP2007033558A - Grid polarizer and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a grid polarizer which has an anti-scratch property and an anti-fouling property, and has a sufficient flexibility and strength. <P>SOLUTION: The grid polarizer comprises: a first layer made of transparent material; second layers which are plurally formed in parallel to each other so as to be extended as long and narrow lines apart from each other on the main surface of the first layer, and include a material having at least 1.0 for the absolute value of the difference between a real part (n) and an imaginary part (κ) of complex refractive index (N=n-iκ); and a third layer formed so as to block separate parts between top parts of the second layers adjoining away from each other by depositing an inorganic oxide or an inorganic nitride obliquely with respect to the main surface of the first layer, wherein air or an inactive gas is included in a space surrounded by the first layer, the second layer and the third layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a grid polarizer used for optical communication, optical recording, a sensor, an image display device, and the like, and a method for producing the same, and in particular, has scratch resistance, antifouling property, and sufficient flexibility. The present invention relates to a grid polarizer having strength and a method for manufacturing the same.

  A grid polarizer is known as a polarizer whose polarization plane can be freely set. This is an optical member having a grid structure in which a large number of linear metals (wires) are arranged in parallel at a constant period. When such a metal grid structure is formed, when the period of the grid is shorter than the wavelength of the incident light, the polarization component parallel to the linear metal forming the grid structure is reflected and the vertical polarization component is Since it transmits, it functions as a polarizer that produces a single polarized light. It has been proposed that this grid polarizer is used as an optical component of an isolator in optical communication, and as a component for increasing light utilization and improving luminance in a liquid crystal display device.

  Patent Document 1 discloses an embedded wire grid polarizer for a visible spectrum as shown in FIG. 17, which includes a first layer 410 having a certain refractive index and a certain refraction separated from the first layer. A second layer 413 having a rate and an array 411 of elongated elements spaced in parallel and sandwiched between the first and second layers to form a plurality of gaps 412 between the elements, A polarizer is proposed that includes an array that provides a refractive index lower than that of the first layer. Patent Document 1 discloses that the gap 412 can contain air, vacuum, water, magnesium fluoride, oil, and hydrocarbon. In the grid polarizer of Patent Document 1, the first layer 411 and the second layer 413 and the array 411 are coupled via a low refractive index material such as magnesium fluoride.

  Patent Document 2 discloses an embedded wire grid polarizer that polarizes an incident light beam as shown in FIG. 18, and includes a base material 414 having one surface, and the incident light disposed on the surface. Each of the grooves 415 between the composite wires 418 are filled with an optical dielectric material, each of the composite wires being It has an in-wire lower structure composed of alternating elongated metal layers 416 and elongated dielectric layers 417, and the above-described inner wire structure composed of alternating elongated metal wires 416 and elongated dielectric layers 417 is at least two. An embedded wire grid polarizer is disclosed that has two elongated metal wires 416 described above. Patent Document 2 includes air, an optically transparent liquid, an adhesive, or a gel as an optical dielectric material filled in the groove 415. A dielectric member 419 is laminated on the composite wire.

  Patent Document 3 discloses a polarizing device having a polarizer as shown in FIG. 19, which includes a light transmitting substrate 420, a grid wire 421 that is sensitive to the surrounding environment disposed on the substrate, and There is disclosed a polarizing device including a sealing enclosing member 423 surrounding the polarizer, and the enclosing member has an inert atmosphere to protect the polarizing element from the surrounding environment. As this inert atmosphere, vacuum and inert gas are disclosed. This hermetic enclosing member is provided so as not to contact the grid wire via a spacer 424 attached to the side of the polarizer.

JP2003-51818A JP 2004-280050 A JP 2005-513547 A

  An object of the present invention is to provide a grid polarizer having scratch resistance and antifouling properties and sufficient flexibility and strength.

  As a result of investigations to achieve the above object, the present inventors have found that the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) is present on the main surface of the first layer made of a transparent material. A second layer containing a material having an absolute value of 1.0 or more is formed by arranging a plurality of elongated and linearly spaced apart layers, and then vapor-depositing obliquely with respect to the main surface of the first layer. By forming a third layer that bridges the top and closes the mouth of the groove between the second layers, air or an inert gas is contained in the space surrounded by the first layer, the second layer, and the third layer. In addition, the inventors have found that a grid polarizer having scratch resistance and antifouling properties and sufficient flexibility and strength can be obtained, and the present invention has been completed based on this finding.

Thus, according to the present invention,
(1) a first layer made of a transparent material;
A second layer containing a material having an absolute value of a difference between a real part n and an imaginary part κ of a complex refractive index (N = n−iκ) of 1.0 or more;
A third layer made of an inorganic oxide or an inorganic nitride,
The second layer is
A plurality of elongated and linearly spaced lines, and sandwiched between a first layer and a third layer,
And the space surrounded by the first layer, the second layer, and the third layer contains air or inert gas,
A grid polarizer is provided.

Also according to the invention,
(2) a first layer made of a transparent material;
A second layer containing a material having an absolute value of a difference between a real part n and an imaginary part κ of a complex refractive index (N = n−iκ) of 1.0 or more;
A third layer made of an inorganic oxide or an inorganic nitride,
The first layer is
The surface is formed in a state where a plurality of elongated and linearly extending convex portions are spaced apart from each other,
The second layer is
On the top surface of the convex portion of the first layer, it is elongated and linearly provided along the convex portion, and is sandwiched between the top surface of the convex portion and the third layer,
And the space surrounded by the first layer, the second layer, and the third layer contains air or inert gas,
Grid polarizer,
And / or (3) Furthermore, the fourth layer containing a material having an absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) of 1.0 or more is a convexity of the first layer. The grid polarizer is provided on the bottom surface of the groove formed between the sections, extending in a line shape along the groove.

Moreover, according to the present invention,
(4) A polarizing element obtained by superimposing the grid polarizer and another polarizing optical member is provided, and (5) as another preferred embodiment, the other polarizing optical member is an absorptive polarizer, and the grid polarizer is provided. The polarizing element in which the polarization transmission axis of the absorbing polarizer and the polarizing transmission axis of the absorptive polarizer are substantially parallel is provided, and (6) a liquid crystal display device including the grid polarizer or the polarizing element is provided.

The first layer constituting the grid polarizer of the present invention is not particularly limited as long as it is made of a transparent material.
Examples of the transparent material include glass and transparent resin, and transparent resin is preferable in consideration of flexibility. The transparent resin preferably has a glass transition temperature of 60 to 200 ° C., more preferably 100 to 180 ° C., from the viewpoint of processability. The glass transition temperature can be measured by differential scanning calorimetry (DSC).

  Specific examples of the transparent resin include polycarbonate resin, polyethersulfone resin, polyethylene terephthalate resin, polyimide resin, polymethyl methacrylate resin, polysulfone resin, polyarylate resin, polyethylene resin, polyvinyl chloride resin, cellulose diacetate, and cellulose triacetate. And alicyclic olefin polymers. Of these, alicyclic olefin polymers are preferred from the viewpoints of transparency, low hygroscopicity, dimensional stability, and processability. Examples of the alicyclic olefin polymer include a cyclic olefin random multi-component copolymer described in JP-A No. 05-310845, a hydrogenated polymer described in JP-A No. 05-97978, and JP-A No. 11-124429. And thermoplastic dicyclopentadiene-based ring-opening polymers and hydrogenated products thereof.

The transparent resin used in the present invention contains coloring agents such as pigments and dyes, fluorescent brighteners, dispersants, heat stabilizers, light stabilizers, ultraviolet absorbers, antistatic agents, antioxidants, lubricants, solvents, etc. An agent may be appropriately blended.
The first layer made of a transparent resin can be obtained by molding the transparent resin by a known method. Examples of the molding method include a cast molding method, an extrusion molding method, and an inflation molding method.

The first layer is usually in the form of a sheet or film, and preferably has a smooth surface with a light transmittance in the visible region of 400 to 700 nm of 80% or more. Moreover, the average thickness of a 1st layer is 5 micrometers-1 mm normally from a viewpoint of handleability, Preferably it is 20-200 micrometers.
Further, the first layer, the retardation _{Re (Re = d × (n} x -n y) defined in the _value, n x, _{n y} in-plane principal refractive index of the first layer measured at the wavelength of 550 nm; d is an average thickness of the first layer) and is not particularly limited. The difference between the retardation Re at any two points in the plane (retardation unevenness) is preferably 10 nm or less, and more preferably 5 nm or less. When the retardation unevenness is large, the brightness of the display surface tends to vary when used in a liquid crystal display device.

  The second layer constituting the grid polarizer of the present invention includes a material having an absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) of 1.0 or more.

  A material whose absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) is 1.0 or more has either a real part or an imaginary part of the complex refractive index that is large. The material can be appropriately selected from materials having a value of 1.0 or more. Specific examples of materials whose absolute value of the difference between the real part and the imaginary part of the complex refractive index is 1.0 or more include metals; inorganic semiconductors such as silicon and germanium; polyacetylene, polypyrrole, polythiophene, poly-p-phenylene, etc. Conductive polymers, and organic conductive materials obtained by doping these conductive resins with dopants such as iodine, boron trifluoride, arsenic pentafluoride, and perchloric acid; conductive resins such as gold and silver on insulating resins Examples thereof include organic-inorganic composite conductive materials obtained by drying a solution in which metal fine particles are dispersed. Among these, a metal material is preferable from the viewpoint of productivity and durability of the grid polarizer. In order to efficiently separate polarized light in the visible range, each of the real part n and the imaginary part κ of the complex refractive index at a temperature of 25 ° C. and a wavelength of 550 nm is preferably such that n is 4.0 or less and κ is 3. 0 or more and the absolute value of the difference | n−κ | is 1.0 or more, more preferably n is 2.0 or less, κ is 4.5 or more, and | n−κ | .0 or more. Examples of the preferable range include silver, aluminum, chromium, indium, iridium, magnesium, palladium, platinum, rhodium, ruthenium, antimony, and tin. Examples of the more preferable range include aluminum, indium. , Magnesium, rhodium, tin and the like. In addition to the above, a material in which n is 3.0 or more and κ is 2.0 or less, preferably a material in which n is 4.0 or more and κ is 1.0 or less is also preferably used. be able to. Examples of such a material include silicon. The complex refractive index N is a theoretical relational expression of electromagnetic waves, and is expressed by N = n−iκ using the refractive index n of the real part and the extinction coefficient κ of the imaginary part.

Although the details are unknown, the value of | n−κ | has the following significance. First, in the case of n <κ, it is shown that κ is larger and n is smaller. The larger κ is, the higher the conductivity and the more free electrons that can vibrate in the longitudinal direction of the second layer. Therefore, it is generated by the incidence of polarized light (polarized light in a direction parallel to the longitudinal direction of the second layer). The electric field becomes stronger and the reflectance for the polarized light increases. Since the width of the second layer is small, electrons do not move in the direction perpendicular to the longitudinal direction of the second layer, and the above effect does not occur for polarized light in the direction perpendicular to the longitudinal direction of the second layer. Polarized light is transmitted. In addition, since the wavelength in the medium of incident light is smaller when n is smaller, the size (line width, pitch, etc.) of the fine concavo-convex structure is relatively small, and is less susceptible to the effects of scattering, diffraction, Light transmittance (polarized light in a direction perpendicular to the second layer) and reflectance (polarized light in a direction parallel to the second layer) are increased.
On the other hand, in the case of n> κ, it is shown that n is larger and κ is smaller. As n increases, the difference in the refractive index n between the second layer and the adjacent portion (air in FIG. 1) increases, and structural birefringence is more likely to occur. On the other hand, if κ is large, light absorption increases, so it is preferable that κ is small in order to prevent light loss. Here, | n−κ | being 1.0 or more indicates that n is larger and κ is smaller.

  The second layer is elongated and extends linearly, and a plurality of the second layers are provided side by side. For example, as shown in FIGS. 5 and 6, on the top surface of the convex portion of the first layer 310 made of a transparent material having a surface shape in which a plurality of elongated linearly extending convex portions are arranged in a separated state, The second layer 311 has a stacked structure. The pitch of the second layer is ½ or less of the wavelength of light used. The narrower the width and height of the second layer, the smaller the absorption of the polarization component in the transmission direction, which is preferable in terms of characteristics. In the grid polarizer used for visible light, the pitch of the second layer is usually 50 to 600 nm, the width of the second layer is usually 25 to 300 nm, and the height of the second layer is 10 to 500 nm. The second layer extends longer than the wavelength of normal light, and preferably extends 800 nm or more.

In the grid polarizer of the present invention, the third layer is made of an inorganic oxide or an inorganic nitride. The inorganic oxide or inorganic nitride preferably has a low refractive index.
Specific examples of the inorganic oxide or inorganic nitride include silicon oxide, aluminum oxide, magnesium oxide, titanium oxide, zinc oxide, zirconium oxide, silicon nitride, and aluminum nitride.
Although a 3rd layer is not specifically limited by the thickness, Preferably it is 5-500 nm, More preferably, it is 10-300 nm.

  In the grid polarizer of the present invention, air or an inert gas is contained in a space surrounded by the first layer, the second layer, and the third layer. When air or an inert gas is included in the space, the polarization rate of the grid polarizer increases. Examples of the inert gas include nitrogen and argon.

Moreover, according to the present invention,
(7) The second layer containing a material having an absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) of 1.0 or more on the main surface of the first layer made of a transparent material. Are elongated and linearly formed, and are arranged side by side at a distance,
By vapor-depositing an inorganic oxide or an inorganic nitride obliquely with respect to the main surface of the first layer, a third layer is formed that closes the separated portion between the tops of the adjacent second layers in a separated state,
Manufacturing method of grid polarizer in which air or inert gas is contained in space surrounded by first layer, second layer and third layer, and / or (8) a plurality of elongated and linearly extending convex portions The absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) on the top surface of the convex portion of the first layer made of a transparent material formed on the surface in a state of being spaced apart side by side Is formed by extending the second layer containing a material of 1.0 or more into a long and narrow line along the convex portion,
By vapor-depositing an inorganic oxide or an inorganic nitride obliquely with respect to the main surface of the first layer, a third layer is formed that closes the separated portion between the tops of the adjacent second layers in a separated state,
A method for producing a grid polarizer, in which air or an inert gas is contained in a space surrounded by the first layer, the second layer, and the third layer;
In addition, the manufacturing method as described in these (7)-(8) is a manufacturing method suitable in order to obtain the grid polarizer as described in said (1)-(6).

  The method of manufacturing the grid polarizer of the present invention is to deposit both inorganic oxides or inorganic nitrides obliquely with respect to the main surface of the first layer, thereby bridging both the tops of the second layers that are spaced apart from each other. It is included as one of the features to form a third layer that closes the mouth of the groove portion.

The vapor deposition is performed obliquely with respect to the main surface of the first layer. 1-3 is a figure which showed an example of the process of forming a 3rd layer.
First, for the second layer 311 arranged in a spaced manner, when performing oblique vapor deposition at an angle from the upper right side of the drawing in the drawing, inorganic oxide or inorganic nitride is deposited on the upper right side of the top of the second layer, As shown in FIG. 1, the vapor deposition film 316-1 grows toward the upper right. Next, when oblique vapor deposition is performed at an angle from the upper left of the page, an inorganic oxide or inorganic nitride is deposited on the upper left side of the top of the second layer, and the vapor deposition film 316-2 is directed toward the upper left as shown in FIG. Growing up. And the vapor deposition film 316-1 grown by vapor deposition from the upper right and the vapor deposition film 316-2 grown by vapor deposition from the upper left approach each other, and the separation portion extends between the tops of the adjacent second layers in a separated state. Will be blocked. When the separated portion is blocked, as shown in FIG. 3, a vapor deposition film 316-3 can be grown on the vapor deposition film 316-1 and the vapor deposition film 316-2. By this oblique deposition process, a third layer is formed, and a grid polarizer in which air or an inert gas is contained in a space surrounded by the first layer, the second layer, and the third layer can be easily obtained.

  Since the grid polarizer of the present invention has scratch resistance and antifouling properties, and has sufficient flexibility and strength, the grid polarizer can be handled easily when it is attached to a liquid crystal display device or the like. Further, when the grid polarizer of the present invention is disposed between the liquid crystal panel of the liquid crystal display device and the backlight device, the light emitted from the backlight can be used effectively and the luminance of the display screen can be improved.

Next, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 7 is a cross-sectional view showing a first embodiment of the grid polarizer of the present invention. 5 and 6 are a perspective view and a cross-sectional view showing a state before the third layer 316 of the grid polarizer shown in FIG. 7 is laminated.
The grid polarizer shown in FIG. 7 has a plurality of elongated protrusions extending in a line on the surface of the first layer. A second layer 311 that is elongated and linearly formed on the top surface of the convex portion is provided along the convex portion. Further, a fourth layer 311 ′ that is elongated and linearly formed on the bottom surface of the groove between the convex portions is provided along the groove, and a third layer 316 is provided on the top surface of the second layer. Yes.
The elongated linearly formed convex portion formed on the surface of the first layer has a structure as shown in FIGS. The pitch of the convex portions arranged on the surface of the first layer is preferably 50 to 600 nm, and the width of the convex portion is shorter than the wavelength of normal light, preferably 25 to 300 nm, and the height of the convex portion. Is preferably 50 to 500 nm. The convex portion extends linearly, and its length is longer than the wavelength of normal light and is usually 800 nm or more.

  The first layer having a long and linearly extending convex portion is not particularly limited by the manufacturing method. A preferred method for producing the first layer is to transfer a linearly extending convex portion onto the surface of a long resin film using a transfer mold having a linearly extending concave portion, preferably a transfer roll. Is included.

  The transfer mold or transfer roll used in this preferred manufacturing method is not particularly limited by the manufacturing method as long as the transfer surface has a long and elongated recess on the transfer surface. For example, a material having a Mohs hardness of 9 or more is processed using a high energy beam, and a tool is formed by forming a protrusion having a width of 600 nm or less at the tip, and the pitch is formed on the surface of the mold member or roll member using the tool. A method of forming an elongated, linearly extending recess, preferably 50 to 600 nm, a recess width of preferably 25 to 300 nm, and a recess depth of preferably 50 to 500 nm.

  FIG. 12 is a diagram illustrating an example of the tool 10. A rectangular parallelepiped with a Mohs hardness of 9 or more is processed with a high energy beam, a groove is carved into the tip surface, and a linear protrusion 11 having a width of 300 nm or less, preferably 200 nm or less is formed at the tip. In FIG. 12, a plurality of linear protrusions are arranged in parallel at a constant pitch.

The shape of the protrusion formed at the tip is not particularly limited, and for example, the cross section cut by a surface perpendicular to the length of the linear protrusion is rectangular, triangular, semicircular, trapezoidal, or these shapes are slightly deformed Can be mentioned. Among these, the one having a rectangular cross section is preferable because the second layer of the material having the absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index can be easily formed.
The arithmetic average roughness (Ra) of the protrusion formed at the tip of the tool is preferably 10 nm or less, more preferably 3 nm or less.

  The protrusion (convex portion) of the tool is formed as a concave portion on the surface of the mold member or roll member, and the concave portion of the tool is formed as a convex portion on the surface of the mold member or roll member. When the cutting tool 10 (FIG. 16; width W1, pitch P1, height H1) is used, the width W2 of the protrusion 11 on the surface of the mold member or roll member is P1-W1, The pitch P2 is P1, and the height H2 of the protrusion 11 is H1 or less. In consideration of this relationship and thermal expansion during transfer, the tool shape corresponding to the concave shape to be formed on the surface of the mold member or roll member can be determined. The width e of the protrusions on both side ends of the tool is preferably W1-25 <e <W1 + 25 (unit: nm) or e = 0 because the pitch of the processed seam portion can be set to a set value.

  Examples of the material having a Mohs hardness of 9 or more used for the tool include diamond, cubic boron nitride, and corundum. These materials are preferably single crystals or sintered bodies. A single crystal is preferable in terms of processing accuracy and tool life, and single crystal diamond or cubic boron nitride is more preferable because of its high hardness, and single crystal diamond is particularly preferable. Examples of the sintered body include metal bonds that use cobalt, steel, tungsten, nickel, bronze, and the like as sintered materials; vitrified bonds that use feldspar, soluble clay, refractory clay, frit, and the like as sintered materials. it can. Of these, diamond metal bonds are preferred.

  Examples of the high energy beam used for manufacturing the tool include a laser beam, an ion beam, and an electron beam. Among these, an ion beam and an electron beam are preferable. In processing using an ion beam, a method of irradiating an ion beam while spraying an active gas such as chlorofluorocarbon or chlorine on the surface of the material (referred to as ion beam assisted chemical processing) is preferable. In electron beam processing, a method of irradiating an electron beam while spraying an active gas such as oxygen gas on the surface of the material (referred to as electron beam assisted chemical processing) is preferable. By these beam-assisted chemical processing, the etching rate can be increased, the reattachment of the sputtered substance can be prevented, and the fine processing can be efficiently performed with high accuracy on the nano order.

  FIG. 13 is a diagram showing an example of a method of forming the recess 21 that is elongated and linearly formed on the peripheral surface of the roll member 20 using the tool obtained above. In FIG. 13, the linear protrusion 11 of the tool 10 is pressed against the circumferential surface of the roll member 20, and the roll member is rotated to cut or grind the roll member circumferential surface.

  The cutting or grinding of the mold member or roll member is preferably performed using a precision fine processing machine. The precision micromachining machine has an X, Y, and Z axis movement accuracy of preferably 100 nm or less, more preferably 50 nm or less, and particularly preferably 10 nm or less. The precision micro-machining machine is preferably installed in a room where the vibration displacement of 0.5 Hz or more is controlled to 50 μm or less, more preferably in a room where the vibration displacement of 0.5 Hz or more is controlled to 10 μm or less. Processing. Further, the cutting or grinding of the mold member or the roll member is preferably performed in a temperature-controlled room whose temperature is controlled within ± 0.5 ° C., more preferably a temperature-controlled room where the temperature is controlled within ± 0.3 ° C.

  The mold member or roll member used for microfabrication is not particularly limited, but the surface of the mold member or roll member is preferably formed of a material having an appropriate hardness, for example, formed by electrodeposition or electroless plating. It is formed of a metal film. The material constituting the metal film is preferably a material that can obtain a metal film having a Vickers hardness of preferably 40 to 350, more preferably 200 to 300, specifically copper, nickel, nickel-phosphorus alloy, palladium. Of these, copper, nickel, and nickel-phosphorus alloys are preferable.

  In FIG. 13, the tool is directly pressed against the roll member to form an elongated, linearly extending recess, but an elongated, linearly extending convex is formed on the mold, and the electric power is formed on the mold. A transfer roll may be produced by a method in which a metal plate is produced by casting or the like, the metal plate is peeled off from the mold, and the metal plate is attached to the peripheral surface of the roll member.

  Using the transfer mold or transfer roll obtained by the above method or the like, a long and elongated protrusion is formed on the surface of the resin film. FIG. 14 is a diagram illustrating an example of a process of forming a long and elongated protrusion on the surface of the resin film 30 with a transfer roll. In FIG. 14, the transfer roll 20 and the roll 21 on the opposite side across the resin film are pressed against the resin film 30, and the shape of the recess extending in the shape of a long line on the peripheral surface of the transfer roll is transferred to the resin film. Yes. The pinching pressure between the transfer roll and the roll on the opposite side is preferably several MPa to several tens of MPa. The temperature during transfer is preferably Tg to (Tg + 100) ° C., where Tg is the glass transition temperature of the transparent resin constituting the resin film. The contact time between the resin film and the transfer roll can be adjusted by the feed speed of the resin film, that is, the roll rotation speed, and is preferably 5 to 600 seconds.

  Another method for forming elongated and linearly protruding parts on the surface of the resin film is to apply a photosensitive transparent resin to a transfer mold or transfer roll and expose it to transfer the elongated and linearly protruding parts. The method of doing is mentioned. Specifically, the photosensitive transparent resin solution was cast, the solvent was removed, and then the transfer roll was pressed and irradiated with light at the same time to cure the photosensitive transparent resin, and elongated in a linear shape. This is a method of forming a convex portion.

  Next, the absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) such as aluminum or silicon on the top surface of the elongated linearly formed convex portion formed on the resin film surface The second layer 311 containing a material having a thickness of 1.0 or more is formed. As shown in FIG. 6, the fourth layer may be formed on the bottom surface of the groove between the second layer and the convex portion on the top surface of the convex portion, or only the second layer may be formed on the top surface of the convex portion. .

  The method for forming the second layer and the fourth layer is not particularly limited. Depending on the materials used, various coatings by vacuum deposition processes such as vacuum deposition, sputtering, and ion plating, and wet processes such as microgravure, screen coating, dip coating, electroless plating, and electrolytic plating Can be used. Of these, vacuum vapor deposition and sputtering are preferred from the viewpoint of the uniformity of the grid structure.

  Hereinafter, the case where a 2nd layer or a 4th layer is formed by sputtering method is illustrated. FIG. 15 is a diagram illustrating an example of a continuous sputtering apparatus. An apparatus 500 shown in FIG. 15 is a DC magnetron sputtering apparatus in which the unwinding roll 501 can be loaded with the resin film formed with the elongated linearly extending projections, and the target 506 can be loaded with the metal to be deposited. It is. The vacuum chamber is evacuated, the film is unwound from the unwinding roll 501, the film is wound around a clean film forming roll 503, and a metal film is formed on the film surface by sputtering from the target 506. The film on which the metal film is formed is wound on a winding roll 504.

  By tilting the direction when sputtering or vapor-depositing the metal with respect to the elongated linearly formed convex portion formed in the film, a portion where the metal film is formed and a portion where the metal film is not formed can be formed. For example, in a resin film in which a convex part extending in a thin and linear shape is formed, if sputtering or the like is performed from the normal direction of the resin film, a metal film is formed on the top surface of the convex part and the bottom surface of the groove part between the convex parts. The metal film is not formed on the side surface of the convex portion. Also, if the same resin film is sputtered obliquely with respect to the film surface in a direction substantially perpendicular to the direction in which the convex portion extends, a metal film is formed on the top half surface of the convex portion and the upper half of one side of the convex portion. However, a metal film is not formed on the bottom surface of the groove between the convex portions, the lower half of one side surface of the convex portion, and the other one side surface. The second layer and the fourth layer can be easily obtained by utilizing the linearity of the metal flying by such sputtering and the grooves between the protrusions and the protrusions.

Next, a third layer is formed on the second layer 311. The third layer can be obtained through the steps shown in FIGS.
The process for forming the third layer is as described above.

FIG. 8 is a cross-sectional view showing a second embodiment of the grid polarizer of the present invention. In the grid polarizer of the second embodiment, a fifth layer 317 is laminated on the third layer of the grid polarizer of the first embodiment. FIG. 4 is a view showing a state in which the fifth layer is laminated on the third layer obtained by the oblique vapor deposition.
The fifth layer 317 is preferably a sheet or film. The fifth layer 317 is not limited to the structure of FIG. 8 and may be a layer made of a transparent material.
The fifth layer is preferably a layer capable of transmitting light, for example, a layer made of a transparent resin composed of cellulose esters such as cellulose acetate, cellulose acetate butyrate, cellulose propionate, polycarbonate, polyolefin, polystyrene, polyester, etc. Organic / inorganic composite layer composed of organoalkoxysilane, inorganic fine particle-dispersed acrylic, etc .; inorganic layer composed of silicon nitride, aluminum nitride, silicon oxide, etc. The fourth layer is preferably made of a resin from the viewpoint of flexibility.

  The method of laminating the fifth layer is not particularly limited, but a method of laminating the film-like fifth layer, applying a coating agent containing the composition forming the fifth layer, and drying or heat Alternatively, a method of curing by light, a vacuum deposition method, an ion plating method, a sputtering method, and the like can be given. The thickness of the fifth layer is not particularly limited. Specifically, it is 50 nm to 500 μm.

FIG. 10 is a diagram showing a third embodiment of the grid polarizer of the present invention. FIG. 9 is a diagram showing a state before the third layer is laminated on the grid polarizer shown in FIG.
As shown in FIG. 9, the grid polarizer has a second layer 311 laminated on a film-like first layer 310 made of a transparent material such as a transparent resin. The second layer 311 is elongated and linearly extends on the surface of the first layer 310. The method for forming the second layer on the first layer 310 is not particularly limited, but can be obtained by, for example, a photolithographic method. As an example of the photolithographic method, (1) a metal film is deposited on the first layer by a method such as vapor deposition or plating, a photosensitive resist film is formed on the metal film, and light of a linear pattern is irradiated. The resist film is cured in accordance with the pattern, the uncured part is removed, the metal film part from which the resist has been removed is etched, and finally the cured resist is removed, or (2) a photosensitive resist on the first layer Form a film, irradiate light with a linear pattern, cure the resist film according to the pattern, remove the uncured part, and form a metal film on the resist with the pattern formed by vapor deposition, sputtering, etc. And a method of removing the last cured resist. Note that a layer of a compound having a reactive group bonded to the inorganic material and a reactive group bonded to the organic material may be formed on the first layer, and the second layer may be formed on the layer.

  In the grid polarizer of the third embodiment, the third layer is provided on the top surface of the second layer 311. The third layer 316 can be formed by the same method as described in the first embodiment. A space 312 is formed between the first layer, the second layer, and the third layer. The space 312 contains air or inert gas.

  FIG. 11 is a cross-sectional view showing a fourth embodiment of the grid polarizer of the present invention. In the grid polarizer of the fourth embodiment, a fifth layer 317 is laminated on the third layer of the grid polarizer of the third embodiment. The fifth layer is the same as that shown in the description of the second embodiment.

  The polarizing element of the present invention is formed by superimposing the grid polarizer and another polarizing optical member. Examples of other polarizing optical members include an absorption polarizer, a retardation element, and a polarization diffraction element. In particular, when the polarizing element of the present invention is used as a brightness enhancement element of a liquid crystal display device, the other polarizing optical member is preferably an absorptive polarizer.

  The absorptive polarizer used in the present invention transmits one of two linearly polarized light intersecting at right angles and absorbs the other. For example, a hydrophilic polymer film such as a polyvinyl alcohol film or an ethylene vinyl acetate partially saponified film adsorbed a dichroic substance such as iodine or a dichroic dye and uniaxially stretched, the hydrophilic polymer film Examples include uniaxially stretched and dichroic substances adsorbed, and polyene oriented films such as polyvinyl alcohol dehydrated products and polyvinyl chloride dehydrochlorinated products. The thickness of the absorbing polarizer is usually 5 to 80 μm.

  The grid polarizer and the absorption polarizer are preferably overlapped so that the polarization transmission axis of the grid polarizer and the polarization transmission axis of the absorption polarizer are substantially parallel. With such an arrangement, natural light can be efficiently converted into linearly polarized light.

  The polarizing element of this invention is not specifically limited by the manufacturing method. For example, the grid polarizer and the other polarizing optical member while simultaneously unwinding the long grid polarizer wound in a roll shape and another long polarizing optical member wound in a roll shape from the roll. And a method including adhering to each other. An adhesive agent can be interposed between the grid polarizer and another polarizing optical member. As a method for bringing the grid polarizer and the other polarizing optical member into close contact with each other, there is a method in which the grid polarizer and the other polarizing optical member are pressed together and sandwiched between nips of two parallelly arranged rolls.

  The liquid crystal display device of the present invention includes the grid polarizer or the polarizing element. The liquid crystal display device includes a liquid crystal panel whose polarization transmission axis can be changed by adjusting a voltage, and two absorption polarizers arranged so as to sandwich the liquid crystal panel. In order to send light to the liquid crystal panel, a backlight device is provided in the transmissive liquid crystal display device and a reflector is provided in the reflective liquid crystal display device on the back side of the display surface.

  The grid polarizer of the present invention has a property of transmitting one of orthogonal linearly polarized light and reflecting the other. Further, the polarizing element of the present invention has a property of transmitting one of orthogonal linearly polarized light and reflecting the other when irradiated with light from the grid polarizer side. In the transmissive liquid crystal display device of the present invention, the grid polarizer and the polarizing element of the present invention (arranged so that the grid polarizer of the polarizing element is on the backlight side) are disposed between the backlight device and the liquid crystal panel. Then, the light emitted from the backlight device is separated into two linearly polarized light by the grid polarizer, one linearly polarized light travels in the direction of the liquid crystal panel, and the other linearly polarized light returns in the direction of the backlight device. The backlight device is usually provided with a reflecting plate, and the linearly polarized light returning to the backlight device is reflected by the reflecting plate and returns to the grid polarizer again. The returned light is again separated into two polarized light by the grid polarizer. By repeating this, the light emitted from the backlight device is effectively used. As a result, light such as a backlight can be efficiently used for displaying an image on the liquid crystal display device, and the screen can be brightened. In the reflective liquid crystal display device, the screen can be brightened by the same principle.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated further more concretely, this invention is not restrict | limited to the following Example. Parts and% are based on weight unless otherwise specified.

(Cutting tools)
A 0.2 mm × 1 mm surface of a cuboid single crystal diamond having a size of 0.2 mm × 1 mm × 1 mm brazed to a SUS shank of 8 mm × 8 mm × 60 mm is irradiated with an argon ion beam to perform cutting. A groove having a width of 70 nm and a depth of 130 nm parallel to a side having a length of 1 mm was carved at a pitch of 150 nm, and approximately 1300 linear protrusions having a width of 80 nm and a height of 130 nm were formed at a pitch of 150 nm to obtain a cutting tool.

(Transfer roll)
Nickel-phosphorus electroless plating with a thickness of 100 μm was applied to the peripheral surface of a stainless steel SUS430 roll having a diameter of 200 mm and a length of 150 mm. Next, the cutting tool formed previously with the linear protrusions is attached to a precision cylindrical grinding machine, and the grinding machine extends to the nickel-phosphorous electroless plating surface of the roll in the circumferential direction of the roll. A linear protrusion having a thickness of 130 nm and a pitch of 150 nm was formed to obtain a transfer roll.
In addition, the fabrication of the cutting tool by focused ion beam machining and the cutting of the nickel-phosphorus electroless plating surface are performed at a temperature of 20.0 ± 0.2 ° C., and the vibration displacement of 0.5 Hz or more by the vibration control system is 10 μm or less In a constant temperature and low vibration room controlled by

Comparative Example 1 (Grid polarizer 0)
Using a nip roll composed of a rubber roll having a diameter of 70 mm and a transfer apparatus equipped with the transfer roll, the surface temperature of the transfer roll is 170 ° C., the surface temperature of the nip roll is 100 ° C., the film transport tension is 1 MPa, and the nip pressure is 15 MPa. By transferring the irregular shape of the transfer roll surface onto the surface of a cycloolefin polymer film (trade name: ZF-14, manufactured by Nippon Zeon Co., Ltd.) having a thickness of 100 μm, the width is 75 nm and the height is 120 nm in parallel with the film flow direction. And the film which has the convex part extended linearly with a pitch of 150 nm was produced.

  Next, by vacuum-depositing aluminum from the normal direction on the surface on which the convex portions of the film are formed, the second layer and the fourth layer made of aluminum having a thickness of 50 nm are formed on the top surfaces of the convex portions and the bottom surfaces of the grooves between the convex portions. A layer was formed. The grid polarizer was cut into a predetermined shape to obtain three sheet grid polarizers 0 as shown in FIG.

  Next, a light guide plate, a light diffusion sheet, and a grid polarizer were sequentially laminated, and a linear light source was installed on the end face of the polarizing plate to obtain a polarized light source device. An absorptive polarizing plate is placed on this polarized light source device so that its polarization transmission axis is parallel to the polarization transmission axis of the grid polarizer, and further a transmissive TN liquid crystal panel is placed thereon, on which another absorption is made. A liquid crystal display device was obtained by placing a polarizing plate (so that the polarization transmission axis was orthogonal to that of the absorption polarizing plate). The initial front luminance of the obtained liquid crystal display device was measured using a luminance meter (trade name: BM-7, manufactured by Topcon Corporation). The results are shown in Table 1.

  Also, set one end of the second grid polarizer to the fixed jig and the other end to the movable jig, and the grid polarizer is set to ± 150 degrees (0 degrees when the grid polarizer is straight) The movable jig was moved so as to be bent, and one cycle of −150 degree bending and +150 degree bending was performed as one cycle (operation speed was 2 seconds / cycle), and 200 cycles were performed. Even after 200 cycles of bending, abnormalities such as peeling on the grid polarizer were not visually observed. A liquid crystal display device was assembled in the same manner as described above using the grid polarizer after bending for 200 cycles, and the front luminance after bending was measured. The results are shown in Table 1.

  Next, steel wool # 0000 was brought into contact with the surface on which the second layer of the grid polarizer was formed at a load of 0.02 MPa, and was reciprocated 20 times to rub the entire surface of the grid polarizer. The grid polarizer after rubbing with steel wool showed anomalies such as fine scratches visually, and the reflectance or transmittance varied in the plane. A liquid crystal display device was assembled in the same manner as described above using the grid polarizer after rubbing with steel wool, and the front luminance after rubbing was measured. The results are shown in Table 1.

(Hard coat agent)
Hexafunctional urethane acrylate oligomer (trade name: NK Oligo U-6HA, Shin-Nakamura Chemical Co., Ltd.) 30 parts, butyl acrylate 40 parts, isobornyl methacrylate 30 parts, and 2,2-dimethoxy-1,2-diphenylethane 10 parts of 1-one was mixed with a homogenizer to obtain an ultraviolet curable hard coat agent.

Example 1
In the same manner as in Comparative Example 1, a grid polarizer 0 was obtained. The surface of the grid polarizer 0 on which the second layer is formed is SiO ₂ perpendicular to the direction in which the second layer extends and tilted by + 75 ° with respect to the normal of the grid polarizer 0 (upper right direction in FIG. 9). Was deposited. The deposited film of SiO ₂ was deposited on the side surface and the top surface of the second layer and grew in the upper right direction on the paper surface of FIG.
Next, SiO ₂ was vapor-deposited from a direction perpendicular to the extending direction of the second layer and inclined by −60 ° with respect to the normal line of the grid polarizer 0 (upper left direction in FIG. 9). The deposited film of SiO ₂ was deposited on the side surface and the top surface of the second layer, and grew in the upper left direction on the paper surface of FIG. Finally, SiO ₂ was vapor-deposited from the normal direction of the grid polarizer 0 (directly above the paper surface of FIG. 9). A transmission electron microscope confirms that the SiO ₂ vapor-deposited film is deposited with an average thickness of 60 nm from the top surface of the second layer, bridges both the top portions of the second layer, and closes the mouth of the groove between the second layers. did. The deposited film of SiO ₂ was also deposited on the side surface of the second layer, and the amount thereof occupied 15% of the groove portion volume existing between the second layers of the grid polarizer 0. The space (85% of the groove volume) closed by the deposited film of SiO ₂ was occupied by air.

Next, the hard coat agent was applied to the surface on which the SiO ₂ vapor deposition film was formed, using a bar coater so that the film thickness after curing was 5 μm. Subsequently, it dried at 80 degreeC for 5 minute (s), irradiated with the ultraviolet-ray (integrated light quantity 300mJ / cm < ² >), the hard-coat agent was hardened, and the grid polarizer 1 was obtained.

  Abnormalities such as peeling and scratches were not visually observed in the grid polarizer 1 after being bent for 200 cycles and rubbed with steel wool. A liquid crystal display device was assembled using these grid polarizers 1 in the same manner as in Comparative Example 1, and the luminance was measured. The results are shown in Table 1.

Comparative Example 2
In the same manner as in Comparative Example 1, a grid polarizer 0 was obtained. A transparent thermoplastic resin film (Zeonor film, manufactured by Nippon Zeon Co., Ltd.) made of an alicyclic olefin polymer having a thickness of 80 μm and coated with a urethane acrylate adhesive (refractive index: 1.48) is applied to a grid polarizer 0. On the surface on which the second layer was formed, three grid polarizers 2 were formed by thermocompression bonding under the conditions of vacuuming for 15 seconds, thermocompression bonding temperature of 80 ° C., pressure bonding pressure of 1 MPa, and holding time of 300 seconds.
The concave portion on the surface of the grid polarizer 0 was filled with a urethane acrylate adhesive. As in Example 1, no abnormalities such as peeling were visually observed in the grid polarizer 2 after being bent for 200 cycles. It was visually observed that the grid polarizer 2 after being rubbed with steel wool had fine scratches. A liquid crystal display device was assembled using these grid polarizers 2 in the same manner as in Example 1, and the luminance was measured. The results are shown in Table 1.

Comparative Example 3
In Example 1, the front luminance of the liquid crystal display device was measured in a state where the grid polarizer 1 was not disposed. The results are shown in Table 1.

The abbreviations in the table are Al = aluminum, HD = hard coat layer, UA = urethane acrylate adhesive, Air = air, SiO ₂ = deposited film.

From the above results,
1) Since the base material is a resin film, it has bending resistance in any case (including the comparative example), and it is understood that the performance does not deteriorate in the “bending” process.
2) In the embodiment, a space surrounded by the first layer, the second layer, and the third layer is maintained, and the space is filled with air. The brightness is higher than the front brightness when no grid polarizer is used (Comparative Example 3). Also, the front brightness is hardly lowered even after rubbing with steel wool. It can be seen that the performance does not deteriorate due to the friction generated inadvertently during the work of assembling into the liquid crystal display device.
3) Comparative Example 1 has the largest initial luminance. However, it can be seen that the front brightness is greatly reduced after friction.
4) In Comparative Example 2, the concave portion of the fine structure is filled with a substance having a large refractive index. Initial brightness is low. Moreover, it turns out that the brightness | luminance fall after rubbing with steel wool is large.

It is a figure which shows the state which the 3rd layer of the grid polarizer of this invention deposited by diagonal vapor deposition. It is a figure which shows the state which the 3rd layer of the grid polarizer of this invention deposited by diagonal vapor deposition. It is a figure which shows the state which the 3rd layer of the grid polarizer of this invention deposited by diagonal vapor deposition. It is a figure which shows the state which laminated | stacked the 5th layer on the 3rd layer of the grid polarizer of this invention. It is a perspective view which shows the state before laminating | stacking a 3rd layer on the 1st embodiment of the grid polarizer of this invention. It is sectional drawing which shows the state before laminating | stacking a 3rd layer on the 1st embodiment of the grid polarizer of this invention. It is sectional drawing which shows the 1st embodiment of the grid polarizer of this invention. It is sectional drawing which shows the 2nd embodiment of the grid polarizer of this invention. It is sectional drawing which shows the state before laminating | stacking a 3rd layer on the 3rd embodiment of the grid polarizer of this invention. It is sectional drawing which shows the 3rd embodiment of the grid polarizer of this invention. It is sectional drawing which shows the 4th embodiment of the grid polarizer of this invention. It is a figure which shows an example of the grinding tool used in order to manufacture the transfer roll used for the manufacturing method of a grid polarizing layer. It is a figure which shows an example of the method of forming a nano-order uneven | corrugated shape in the surrounding surface of a roll using a grinding tool. It is a figure which shows an example of the process of forming uneven | corrugated shape on the resin film surface with a transfer roll. It is a figure which shows an example of a continuous sputtering apparatus. It is a figure which shows an example of the front-end | tip structure of a cutting tool. It is a figure which shows the conventional embedded type | mold wire grid polarizer. It is a figure which shows the conventional embedded wire grid polarizer. It is a figure which shows the conventional grid polarizer.

Explanation of symbols

310: first layer 311: second layer 311 ′: fourth layer 316: third layer 316-1, 316-2, 316-3: vapor deposition film 327: fifth layer

Claims (8)

A first layer of transparent material;
A second layer containing a material having an absolute value of a difference between a real part n and an imaginary part κ of a complex refractive index (N = n−iκ) of 1.0 or more;
A third layer made of an inorganic oxide or an inorganic nitride,
The second layer is
A plurality of elongated and linearly spaced lines, and sandwiched between a first layer and a third layer,
And the space surrounded by the first layer, the second layer, and the third layer contains air or inert gas,
Grid polarizer. A first layer of transparent material;
A second layer containing a material having an absolute value of a difference between a real part n and an imaginary part κ of a complex refractive index (N = n−iκ) of 1.0 or more;
A third layer made of an inorganic oxide or an inorganic nitride,
The first layer is
The surface is formed in a state where a plurality of elongated and linearly extending convex portions are spaced apart from each other,
The second layer is
On the top surface of the convex portion of the first layer, it is elongated and linearly provided along the convex portion, and is sandwiched between the top surface of the convex portion and the third layer,
And the space surrounded by the first layer, the second layer, and the third layer contains air or inert gas,
Grid polarizer.   Further, a fourth layer containing a material having an absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) of 1.0 or more is formed between the convex portions of the first layer. The grid polarizer according to claim 2, wherein the grid polarizer is provided on the bottom surface of the substrate so as to be elongated and linear along the groove.   A polarizing element obtained by superimposing the grid polarizer according to claim 1 and another polarizing optical member.   The polarizing element according to claim 4, wherein the other polarizing optical member is an absorptive polarizer, and a polarization transmission axis of the grid polarizer and a polarization transmission axis of the absorption polarizer are substantially parallel.   A liquid crystal display device provided with the grid polarizer in any one of Claims 1-3, or the polarizing element in any one of Claims 4-5. A second layer containing a material having an absolute value of the difference between the real part n and the imaginary part κ of the complex refractive index (N = n−iκ) of 1.0 or more is elongated on the main surface of the first layer made of a transparent material. Extending in a line and spaced apart to form a plurality,
By vapor-depositing an inorganic oxide or an inorganic nitride obliquely with respect to the main surface of the first layer, a third layer is formed that closes the separated portion between the tops of the adjacent second layers in a separated state,
A method for producing a grid polarizer, wherein air or an inert gas is contained in a space surrounded by a first layer, a second layer, and a third layer. The real part of the complex refractive index (N = n−iκ) is formed on the top surface of the convex part of the first layer made of a transparent material formed on the surface in a state where a plurality of elongated linearly extending convex parts are arranged side by side. forming a second layer containing a material having an absolute value of a difference between n and the imaginary part κ of 1.0 or more and extending along the convex portion in a linear shape;
By vapor-depositing an inorganic oxide or an inorganic nitride obliquely with respect to the main surface of the first layer, a third layer is formed that closes the separated portion between the tops of the adjacent second layers in a separated state,
A method for producing a grid polarizer, wherein air or an inert gas is contained in a space surrounded by a first layer, a second layer, and a third layer.

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