WO2011007587A1 - 偏光板、その製造方法、及びそれを用いた液晶表示装置 - Google Patents
偏光板、その製造方法、及びそれを用いた液晶表示装置 Download PDFInfo
- Publication number
- WO2011007587A1 WO2011007587A1 PCT/JP2010/050694 JP2010050694W WO2011007587A1 WO 2011007587 A1 WO2011007587 A1 WO 2011007587A1 JP 2010050694 W JP2010050694 W JP 2010050694W WO 2011007587 A1 WO2011007587 A1 WO 2011007587A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- film
- polarizing plate
- protective film
- cellulose ester
- treatment
- Prior art date
Links
Images
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
- G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
- G02B5/3041—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
- G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
- G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B15/00—Layered products comprising a layer of metal
- B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/133528—Polarisers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2457/00—Electrical equipment
- B32B2457/20—Displays, e.g. liquid crystal displays, plasma displays
- B32B2457/202—LCD, i.e. liquid crystal displays
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F2201/00—Constructional arrangements not provided for in groups G02F1/00 - G02F7/00
- G02F2201/50—Protective arrangements
Definitions
- the present invention relates to a polarizing plate, a method for producing the same, and a liquid crystal display device using the same. More specifically, the present invention relates to a polarizing plate that can be produced by a production method that is safe on the work and has a low burden on the environment, using a protective film having excellent adhesion to a polarizer. The present invention also relates to a liquid crystal display device using the polarizing plate and having a high viewing angle and high visibility.
- polarizing plate protective film polymer films such as cellulose ester, polyethylene terephthalate (PET), cycloolefin polymer (COP), and polycarbonate (PC) are known. Many methods of bonding these to a polarizer typified by polyvinyl alcohol (PVA) are known.
- PVA polyvinyl alcohol
- a cellulose ester film is smoothly used for adhesion and drying with a PVA polarizer due to its appropriate moisture permeability, and is used more widely than other thermoplastic films.
- hydrophilic treatment by alkali saponification, corona treatment, or plasma treatment is essential before the bonding step with PVA.
- alkali saponification is the most widely used method.
- a high-temperature, high-concentration alkaline aqueous solution is used, workability and environmental suitability are poor.
- diacetyl cellulose which has been applied to optical films such as ⁇ / 4 plates for a long time, undergoes alkali saponification, so that part of the film dissolves in the alkali saponification solution, and the deposited matter contaminates the process. There was also a problem. Therefore, surface hydrophilization other than alkali saponification is required.
- Corona treatment and plasma treatment have been widely studied as surface hydrophilization treatments instead of alkali saponification (see, for example, Patent Documents 1 and 2).
- the present invention has been made in view of the above problems and situations, and the solution is to use a protective film excellent in adhesiveness with a polarizer, and a manufacturing method that is safe on the work and has little burden on the environment. And a manufacturing method thereof, and a liquid crystal display device using the polarizing plate and having a high viewing angle and high visibility (high contrast, etc.).
- polarizing plate in which both surfaces of the polarizer are sandwiched between protective films, at least one of the protective films is a protective film subjected to hydrophilic treatment by either plasma treatment or corona treatment, and the protective film is hydrophilized.
- a polarizing plate characterized in that the previous surface energy satisfies the following formula (SI) and the surface energy after the hydrophilic treatment of the protective film satisfies the following formula (SII).
- ⁇ sh represents a hydrogen bond component of surface energy
- ⁇ sp represents a dipole component.
- the protective film is a retardation film, the in-plane retardation value Ro (590) defined by the following formula (RI) is in the range of 30 to 90 nm, and the thickness defined by the following formula (RII) 3.
- Ro (590) (n x ⁇ n y ) ⁇ d (nm)
- Rt (590) ⁇ (n x + n y ) / 2 ⁇ n z ⁇ ⁇ d (nm)
- Ro (590) represents the in-plane retardation value in the film at a wavelength of 590 nm
- Rt (590) represents the retardation value in the thickness direction in the film at 590 nm
- d represents the thickness of the optical film (nm)
- n x represents the maximum refractive index in the plane of the film at 590 nm, also referred to as a slow axis direction of the refractive index.
- n y represents a refractive index in the direction perpendicular to the slow axis in the film plane at 590 nm
- n z represents the refractive index of the film in the thickness direction of 590 nm.
- hydrophilic treatment-treated protective film contains a cellulose ester having a solubility parameter (SP value) of 12.0 or more and 13.0 or less.
- SP value solubility parameter
- any one of the first to sixth items, wherein the protective film subjected to the hydrophilic treatment is a film containing diacetyl cellulose having an acetyl substitution degree of 2.1 or more and less than 2.5.
- the polarizing plate as described in a term.
- a method for producing a polarizing plate in which both surfaces of a polarizer are sandwiched between protective films comprising a step of subjecting at least one protective film to a hydrophilic treatment by either plasma treatment or corona treatment, and A method for producing a polarizing plate, wherein the surface energy of the protective film before the hydrophilic treatment satisfies the following formula (SI) and the surface energy of the protective film after the hydrophilic treatment satisfies the following formula (SII): .
- ⁇ sh represents a hydrogen bond component of surface energy
- ⁇ sp represents a dipole component.
- a liquid crystal display device which is a polarizing plate produced by the method for producing a polarizing plate described in the above.
- a polarizing plate that can be produced by a production method that is safe on the work and has little burden on the environment, and a method for producing the same, using a protective film excellent in adhesion to a polarizer.
- a liquid crystal display device using the polarizing plate and having a high viewing angle and high visibility can be provided.
- ⁇ sh / ⁇ sp indicates the magnitude of the ratio of hydrogen bonding components in the surface energy, and generally increases as the hydrophilic treatment proceeds.
- the diacetyl cellulose (DAC) is adjustable to a film having a ratio ( ⁇ sh / ⁇ sp ) of a hydrogen bond component ( ⁇ sh ) and a dipole component ( ⁇ sp ) of the surface energy of 0.25 or more, It can surface processing without degradation of the substrate to the same surface energy state and saponification (state satisfying the above relational expression (SII)), i.e., the protective film before hydrophilization treatment 0.25 ⁇ gamma It was found that may satisfy the h / ⁇ sp.
- the film it is possible to hydrophilize the film while maintaining its physical properties by previously plasma-treating the surface rich in hydrogen bonding components. Since the plasma treatment has an effect of increasing the surface unevenness of the polarizing plate protective film, it contributes to improving the adhesion to the polarizer surface by the anchor effect.
- the unevenness is too large, the haze on the film surface increases and the contrast in the liquid crystal display device is lowered, but the surface roughness Ra (centerline average roughness) is in an appropriate range (2.0 to 10.0 nm). Then, it can control to suitable contrast.
- the method according to the present invention makes it possible to achieve the above-mentioned appropriate surface roughness range.
- the schematic diagram which shows the procedure of an internal haze value evaluation method (a) The state which dripped glycerin on the slide glass is shown. (B) The state which put the sample film on glycerol is shown. (C) The state which dripped glycerin on the sample film is shown. (D) A state in which a cover glass is placed on glycerin.
- Schematic showing an example of a plasma processing apparatus of a single frequency high frequency voltage application method Schematic showing an example of a plasma processing apparatus of a two-frequency high-frequency voltage application method
- the polarizing plate of the present invention is a protective film in which at least one protective film is hydrophilized by either plasma treatment or corona treatment in a polarizing plate in which both sides of a polarizer are sandwiched between protective films,
- the surface energy of the protective film before the hydrophilic treatment satisfies the formula (SI)
- the surface energy of the protective film after the hydrophilic treatment satisfies the formula (SII).
- the value of the center line average roughness (Ra) of the surface of the protective film subjected to the hydrophilic treatment is in the range of 2.0 to 10.0 nm. It is preferable that Further, the hydrophilically treated protective film is a retardation film, and an in-plane retardation value Ro (590) defined by the formula (RI) is in a range of 30 to 90 nm, and the (RII) The retardation value Rt (590) in the thickness direction defined by is preferably in the range of 70 to 300 nm. Furthermore, it is preferable that the internal haze of the hydrophilic treatment-treated protective film is 0.1 or less.
- the hydrophilic protective film is preferably a film containing a cellulose ester.
- the hydrophilic protective film contains a cellulose ester having a solubility parameter (SP value) of 12.0 or more and 13.0 or less.
- the said protective film by which the said hydrophilic treatment was carried out is a film containing the diacetyl cellulose whose acetyl substitution degree is 2.1 or more and less than 2.5.
- the polarizing plate of the present invention can be suitably used for a liquid crystal display device comprising a liquid crystal cell and two polarizing plates arranged on both sides thereof.
- At least one of the protective films constituting the polarizing plate of the present invention is a protective film that has been subjected to a hydrophilic treatment by either plasma treatment or corona treatment, and the surface energy of the protective film before the hydrophilic treatment is represented by the following formula ( SI) and the surface energy after the hydrophilic treatment of the protective film satisfies the following formula (SII).
- ⁇ sh represents a hydrogen bond component of surface energy
- ⁇ sp represents a dipole component.
- the ratio ( ⁇ sh / ⁇ sp ) between the hydrogen bond component and the dipole component of the surface free energy before the hydrophilization treatment is preferably in the range of 0.28 to 1.0. More preferably, it is in the range of 0.30 to 0.50.
- hydrophilic treatment such as plasma treatment or corona treatment needs to be carried out under strong conditions, in which case the film surface is subjected to thermal damage or the like, and the transparency of the film is significantly impaired.
- the ratio ( ⁇ sh / ⁇ sp ) between the hydrogen bond component and the dipole component of the surface free energy before the hydrophilization treatment is greater than 1.5, the winding shape in film production affirmation becomes worse.
- the ratio ( ⁇ sh / ⁇ sp ) between the hydrogen bond component and the dipole component of the surface free energy before the hydrophilization treatment is more preferably less than 0.5.
- the ratio ( ⁇ sh / ⁇ sp ) between the hydrogen bond component and the dipole component of the surface free energy after the hydrophilic treatment is preferably in the range of 1.8 to 3.5, more preferably 2.0. Within the range of ⁇ 3.0. When it is smaller than 3.0, the front contrast ratio of the liquid crystal display device is further improved.
- Means for changing the ratio of the surface free energy hydrogen bond component to the dipole component include the change in the degree of substitution of cellulose acetate, the change in the number of carbon atoms in the substituent, the structure and amount of the additive To make changes. By using these factors in combination, the ratio of the surface free energy hydrogen bond component to the dipole component can be variously changed.
- the surface energy of the protective film before the hydrophilic treatment satisfies the formula (SI)
- the surface energy of the protective film after the hydrophilic treatment is the formula (SII). It is necessary to control by selection of the material type of the protective film and hydrophilization surface treatment conditions so as to satisfy.
- As a more specific achievement means for controlling the surface free energy ( ⁇ sh / ⁇ sp ) before or after the hydrophilization treatment for example, as the acyl group substitution rate of cellulose acetate is increased, ⁇ sh / ⁇ sp is decreased.
- ⁇ sh / ⁇ sp large number of carbon atoms in the acyl group substituted at the cellulose acetate is decreased, the more ⁇ sh / ⁇ sp increasing the addition amount of the hydrophobic compounds, such as plasticizers decreases .
- the value of ⁇ sh / ⁇ sp can be increased as the alkali treatment concentration and the hydrophilic treatment time are increased. Moreover, these combinations may be sufficient.
- the surface free energy of the film was measured as follows.
- the protective film after the hydrophilic treatment according to the present invention preferably has an internal haze of 0.1 or less, more preferably 0.05 or less, and still more preferably 0.03 or less.
- the internal haze is a haze generated by a scattering factor inside the film, and the internal is a portion of 5 ⁇ m or more from the film surface.
- This internal haze is measured by a haze meter by dropping a solvent having a refractive index of ⁇ 0.05 on the film interface to make the haze on the film surface negligible as much as possible.
- Haze meter (turbidity meter) (model: NDH 2000, manufactured by Nippon Denshoku Co., Ltd.)
- the light source uses a 5V9W halogen bulb, and the light receiving unit uses a silicon photocell (with a relative visibility filter).
- the present invention is characterized in that the value is 0.05 or less in the haze measurement of a film when a solvent having a refractive index of ⁇ 0.05 is used as the film interface in this apparatus.
- the measurement was performed according to JIS K-7136.
- the blank haze 1 of a measuring instrument other than a film is measured.
- the haze 2 including the sample is measured by the following procedure. 4).
- Glycerin (0.05 ml) is dropped on the slide glass (see FIG. 1A). 5.
- a sample film to be measured is placed thereon so that air bubbles do not enter (see FIG. 1B).
- Glycerin (0.05 ml) is dropped on the sample film (see FIG. 1C). 7).
- a cover glass is placed thereon (see FIG. 1 (d)).
- the laminate prepared as described above from above, cover glass / glycerin / sample film / glycerin / slide glass) is set on a haze meter and haze 2 is measured.
- (Haze 2) ⁇ (Haze 1) (Internal haze of the cellulose ester film according to the present invention) is calculated.
- the cellulose ester film was prepared after conditioning at 23 ° C. and 55% RH for 5 hours or more, and all the above haze measurements were performed at 23 ° C. and 55% RH.
- the glass and glycerin used in the above measurement are as follows.
- the protective film which concerns on this invention as a raw material
- it is preferable that it is a film containing a cellulose ester.
- the protective film is a film containing diacetylcellulose having an acetyl substitution degree of 2.1 or more and less than 2.5, and the surface energy before hydrophilization treatment of the film satisfies the formula (SI), and This is preferable in that the surface energy after the hydrophilic treatment is easily adjusted so as to satisfy the formula (SII).
- the cellulose as a raw material of the cellulose ester according to the present invention is not particularly limited, and examples thereof include cotton linter, wood pulp, and kenaf. Moreover, the cellulose ester obtained from them can be mixed and used in arbitrary ratios, respectively.
- the cellulose ester used in the present invention can be produced by a known method. Specifically, it can be synthesized with reference to the method described in JP-A-10-45804.
- acetyl celluloses such as Daicel LM80, L20, L30, L40, and L50, Eastman Chemical Co. Ca398-3, Ca398-6, Ca398-10, Ca398-30, and Ca394-60S.
- the total amount (ppm) of calcium and magnesium and the amount of acetic acid (ppm) contained in the cellulose ester film according to the present invention preferably satisfy the following relational expression (3).
- Relational expression (3) 1 ⁇ (acetic acid amount (ppm)) / (total amount of calcium and magnesium (ppm)) ⁇ 30
- Calcium and magnesium are contained in the cellulose ester used as the raw material for the cellulose ester film, but metal oxides and metal hydroxides are used to neutralize and stabilize the acid catalyst (especially sulfuric acid) added to the cellulose ester production process.
- And may be added as a metal salt (inorganic acid salt, organic acid salt).
- the total amount (ppm) of calcium and magnesium contained in the cellulose ester film referred to in the present invention refers to the total amount thereof.
- acetic anhydride and acetic acid are used as reaction solvents and esterifying agents. Unreacted acetic anhydride is hydrolyzed by a reaction stopper (water, alcohol, acetic acid, etc.) to produce acetic acid.
- a reaction stopper water, alcohol, acetic acid, etc.
- the amount of acetic acid (ppm) contained in the cellulose ester film referred to in the present invention refers to the total amount of residual acetic acid and free acetic acid.
- the total amount of calcium and magnesium (ppm) / acetic acid amount (ppm) is preferably 1 or more and 30 or less.
- it indicates that the amount of acetic acid is small relative to the amount of calcium and magnesium, but light scattering due to calcium and magnesium metal salts occurs, which lowers the contrast, which is not preferable.
- it is larger than 30, it indicates that the acetic acid is in an excessive amount with respect to the amounts of calcium and magnesium.
- the cellulose ester is bonded to the polarizer, the deterioration of the polarizer is accelerated by acetic acid.
- the total amount of calcium and magnesium contained in the cellulose ester film is preferably 5 to 130 ppm, more preferably 5 to 80 ppm, and still more preferably 5 to 50 ppm.
- the amount of acetic acid contained in the cellulose ester film is preferably 20 to 500 ppm, more preferably 25 to 250 ppm, and still more preferably 30 to 150 ppm.
- a known method can be used for the determination of calcium and magnesium contained in the cellulose ester film. For example, after the dried cellulose ester is completely burned, a pretreatment in which ash is dissolved in hydrochloric acid is performed. It can be measured by atomic absorption method. The measured value is obtained in units of ppm as the calcium and magnesium contents in 1 g of the completely dry cellulose ester.
- acetic acid contained in the cellulose ester film For quantification of acetic acid contained in the cellulose ester film, a known method can be used. For example, the following method can be used. The film is dissolved in methylene chloride, and methanol is added to perform reprecipitation. The amount of acetic acid can be obtained by filtering the supernatant and measuring the supernatant with gas chromatography.
- the solubility parameter (SP value) of the cellulose ester used in the present invention is from the viewpoint of the amount of energy required for hydrophilization treatment, prevention of deterioration of the transparency of the substrate, prevention of fluctuations due to retardation and dimensions due to temperature and humidity, and the like. It is desirable that it is 12.0 or more and 13.0 or less.
- the SP value is one of the important parameters for predicting the hydrophilicity / hydrophobicity of various chemical substances and can be defined from the heat of molar evaporation ⁇ H and the molar volume V in regular solution theory.
- the SP value can be predicted empirically, and can be obtained by calculation using parameters of Hoy, Fedors, and Small.
- the SP values according to the present invention were calculated using Fedors parameters that are rich in parameters and can be applied to a wide range of compounds.
- the unit is the square root of the value obtained by dividing the cohesive energy density ⁇ E by the molar volume V, and (cm 3 / cal) 1/2 is used.
- the parameters of Fedors are described in References: Basic Science of Coatings by Yuji Harada, Tsuji Shoten (1977), p54-57.
- cellulose ester film ⁇ Additives for cellulose ester film>
- the cellulose ester used in the present invention depends on the application as long as the surface energy before hydrophilization treatment of the film satisfies the above formula (SI) and the surface energy after hydrophilization treatment satisfies the above formula (SII).
- Various additives hydrolysis inhibitor, retardation adjusting agent, plasticizer, ultraviolet absorber, antioxidant, acid scavenger, fine particles, etc.
- hydrolysis inhibitor for example, a mixture of ester compounds in which at least one of the pyranose structure or furanose structure is 1 to 12 and a part of the OH group of the structure is esterified can be preferably used. .
- the ratio of esterification of an ester compound in which at least one of the pyranose structure or furanose structure is 1 to 12 and all or part of the OH groups of the structure is esterified is present in the pyranose structure or furanose structure. It is preferable that it is 70% or more of the OH group.
- ester compounds are collectively referred to as sugar ester compounds.
- ester compounds include the following.
- Glucose galactose, mannose, fructose, xylose or arabinose, lactose, sucrose, nystose, 1F-fructosyl nystose, stachyose, maltitol, lactitol, lactulose, cellobiose, maltose, cellotriose, maltotriose, raffinose or kestose .
- gentiobiose gentiotriose
- gentiotetraose gentiotetraose
- xylotriose galactosyl sucrose
- sucrose for example, sucrose, kestose, nystose, 1F-fructosyl nystose, stachyose and the like are preferable, and sucrose is more preferable.
- Oligosaccharide ester compounds can also be used as compounds having 1 to 12 at least one pyranose structure or furanose structure.
- the said ester compound is a compound which condensed 1 or more and 12 or less of at least 1 sort (s) of the pyranose structure or furanose structure represented with the following general formula (A).
- R 11 to R 15 and R 21 to R 25 each represents an acyl group having 2 to 22 carbon atoms or a hydrogen atom, m and n each represents an integer of 0 to 12, and m + n represents an integer of 1 to 12.
- R 11 to R 15 and R 21 to R 25 are preferably a benzoyl group or a hydrogen atom.
- the benzoyl group may further have a substituent R 26 , and examples thereof include an alkyl group, an alkenyl group, an alkoxyl group, and a phenyl group, and these alkyl group, alkenyl group, and phenyl group have a substituent. May be.
- the cellulose ester film according to the present invention preferably contains 2 to 20% by mass of a hydrolysis inhibitor, particularly preferably 5 to 15% by mass.
- phase difference adjusting agent for example, an ester compound represented by the following general formula (1) can be preferably used.
- B is a hydroxy group or carboxylic acid residue
- G is an alkylene glycol residue having 2 to 12 carbon atoms, an aryl glycol residue having 6 to 12 carbon atoms, or an oxyalkylene glycol residue having 4 to 12 carbon atoms.
- A represents an alkylene dicarboxylic acid residue having 4 to 12 carbon atoms or an aryl dicarboxylic acid residue having 6 to 12 carbon atoms, and n represents an integer of 1 or more.
- a hydroxy group or carboxylic acid residue represented by B an alkylene glycol residue or oxyalkylene glycol residue or aryl glycol residue represented by G, an alkylene dicarboxylic acid residue represented by A or It is composed of an aryl dicarboxylic acid residue and can be obtained by the same reaction as that of a normal ester compound.
- Examples of the carboxylic acid component of the ester compound represented by the general formula (1) include acetic acid, propionic acid, butyric acid, benzoic acid, p-tert-butylbenzoic acid, orthotoluic acid, metatoluic acid, p-toluic acid, and dimethylbenzoic acid. , Ethyl benzoic acid, normal propyl benzoic acid, aminobenzoic acid, acetoxybenzoic acid, aliphatic acid and the like, and these can be used as one kind or a mixture of two or more kinds, respectively.
- alkylene glycol component having 2 to 12 carbon atoms of the ester compound represented by the general formula (1) examples include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, , 3-butanediol, 1,2-propanediol, 2-methyl 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol ( Neopentyl glycol), 2,2-diethyl-1,3-propanediol (3,3-dimethylolpentane), 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolheptane) ), 3-methyl-1,5-pentanediol 1,6-hexanediol, 2,2,4-trimethyl 1,3-pentanedio And
- alkylene glycols having 2 to 12 carbon atoms are particularly preferable because of excellent compatibility with cellulose esters.
- Examples of the oxyalkylene glycol component having 4 to 12 carbon atoms of the ester compound represented by the general formula (1) include diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene glycol. Yes, these glycols can be used as one or a mixture of two or more.
- alkylene dicarboxylic acid component having 4 to 12 carbon atoms of the ester compound represented by the general formula (1) examples include succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, and dodecane. There exist dicarboxylic acid etc., and these are each used as a 1 type, or 2 or more types of mixture.
- Examples of the arylene dicarboxylic acid component having 6 to 12 carbon atoms include phthalic acid, terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, and the like.
- the ester compound represented by the general formula (1) has a number average molecular weight of preferably 300 to 1500, more preferably 400 to 1000.
- the acid value is 0.5 mgKOH / g or less, the hydroxyl value is 25 mgKOH / g or less, more preferably the acid value is 0.3 mgKOH / g or less, and the hydroxyl value is 15 mgKOH / g or less.
- the cellulose ester film used in the present invention preferably contains a retardation adjusting agent in an amount of 0.1 to 30% by mass, particularly 0.5 to 10% by mass of the cellulose ester film.
- the cellulose ester film used for this invention can contain a plasticizer as needed.
- the plasticizer is not particularly limited, but preferably a polycarboxylic acid ester plasticizer, a glycolate plasticizer, a phthalate ester plasticizer, a fatty acid ester plasticizer and a polyhydric alcohol ester plasticizer, a polyester It is selected from plasticizers, acrylic plasticizers and the like.
- At least one is preferably a polyhydric alcohol ester plasticizer.
- the polyhydric alcohol ester plasticizer is a plasticizer composed of an ester of a divalent or higher aliphatic polyhydric alcohol and a monocarboxylic acid, and preferably has an aromatic ring or a cycloalkyl ring in the molecule.
- a divalent to 20-valent aliphatic polyhydric alcohol ester is preferred.
- the polyhydric alcohol preferably used in the present invention is represented by the following general formula (a).
- R 1 represents an n-valent organic group
- n represents a positive integer of 2 or more
- the OH group represents an alcoholic and / or phenolic hydroxyl group.
- Examples of preferable polyhydric alcohols include the following.
- triethylene glycol triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylolpropane, and xylitol are preferable.
- monocarboxylic acid used for polyhydric alcohol ester there is no restriction
- the carboxylic acid used in the polyhydric alcohol ester may be one kind or a mixture of two or more kinds. Moreover, all the OH groups in the polyhydric alcohol may be esterified, or a part of the OH groups may be left as they are.
- the glycolate plasticizer is not particularly limited, but alkylphthalylalkyl glycolates can be preferably used.
- alkyl phthalyl alkyl glycolates include methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, octyl phthalyl octyl glycolate, methyl phthalyl ethyl Glycolate, ethyl phthalyl methyl glycolate, ethyl phthalyl propyl glycolate, methyl phthalyl butyl glycolate, ethyl phthalyl butyl glycolate, butyl phthalyl methyl glycolate, butyl phthalyl ethyl glycolate, propyl phthalyl butyl glycol Butyl phthalyl propyl glycolate, methyl phthalyl octyl glycolate, ethyl phthalyl octyl glycolate, octyl phthalyl
- phthalate ester plasticizer examples include diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, and dicyclohexyl terephthalate.
- citrate plasticizer examples include acetyl trimethyl citrate, acetyl triethyl citrate, and acetyl tributyl citrate.
- fatty acid ester plasticizers examples include butyl oleate, methylacetyl ricinoleate, and dibutyl sebacate.
- phosphate ester plasticizer examples include triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, and the like.
- the polyvalent carboxylic acid ester compound is composed of an ester of a divalent or higher, preferably a divalent to 20valent polyvalent carboxylic acid and an alcohol.
- the aliphatic polyvalent carboxylic acid is preferably divalent to 20-valent, and in the case of an aromatic polyvalent carboxylic acid or alicyclic polyvalent carboxylic acid, it is preferably trivalent to 20-valent.
- the polyvalent carboxylic acid is represented by the following general formula (b).
- R 2 (COOH) m (OH) n
- R 2 is an (m + n) -valent organic group
- m is a positive integer of 2 or more
- n is an integer of 0 or more
- a COOH group is a carboxyl group
- an OH group is an alcoholic or phenolic hydroxyl group
- the molecular weight of the polyvalent carboxylic acid ester compound is not particularly limited, but the molecular weight is preferably in the range of 300 to 1,000, and more preferably in the range of 350 to 750. The larger one is preferable in terms of improvement in retention, and the smaller one is preferable in terms of moisture permeability and compatibility with cellulose ester.
- the alcohol used for the polyvalent carboxylic acid ester may be one kind or a mixture of two or more kinds.
- the acid value of the polycarboxylic acid ester compound is preferably 1 mgKOH / g or less, more preferably 0.2 mgKOH / g or less. Setting the acid value in the above range is preferable because the environmental fluctuation of the retardation is also suppressed.
- the acid value refers to the number of milligrams of potassium hydroxide necessary to neutralize the acid (carboxyl group present in the sample) contained in 1 g of the sample.
- the acid value is measured according to JIS K0070.
- Particularly preferred polyvalent carboxylic acid ester compounds include triethyl citrate, tributyl citrate, acetyl triethyl citrate (ATEC), acetyl tributyl citrate (ATBC), benzoyl tributyl citrate, acetyl triphenyl citrate, acetyl tribenzyl citrate Rate, dibutyl tartrate, diacetyl dibutyl tartrate, tributyl trimellitic acid, tetrabutyl pyromellitic acid and the like.
- ATEC acetyl triethyl citrate
- ATBC acetyl tributyl citrate
- benzoyl tributyl citrate acetyl triphenyl citrate
- acetyl tribenzyl citrate Rate dibutyl tartrate
- diacetyl dibutyl tartrate diacetyl dibutyl tartrate
- UV absorber The ultraviolet absorber is intended to improve durability by absorbing ultraviolet light having a wavelength of 400 nm or less, and the transmittance at a wavelength of 370 nm is particularly preferably 10% or less, more preferably 5% or less. Preferably it is 2% or less.
- the ultraviolet absorber used is not particularly limited, for example, oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, triazine compounds, nickel complex compounds, inorganic powders, etc. Can be mentioned.
- the UV absorbers preferably used in the present invention are benzotriazole UV absorbers, benzophenone UV absorbers, and triazine UV absorbers, particularly preferably benzotriazole UV absorbers and benzophenone UV absorbers. .
- a discotic compound such as a compound having a 1,3,5 triazine ring is also preferably used as an ultraviolet absorber.
- the polarizing plate protective film of the present invention preferably contains two or more ultraviolet absorbers.
- a polymeric ultraviolet absorber can be preferably used, and in particular, a polymer type ultraviolet absorber described in JP-A-6-148430 is preferably used.
- the method of adding the UV absorber can be added to the dope after dissolving the UV absorber in an alcohol such as methanol, ethanol or butanol, an organic solvent such as methylene chloride, methyl acetate, acetone or dioxolane, or a mixed solvent thereof. Or you may add directly in dope composition.
- an alcohol such as methanol, ethanol or butanol
- an organic solvent such as methylene chloride, methyl acetate, acetone or dioxolane, or a mixed solvent thereof.
- inorganic powders that do not dissolve in organic solvents use a dissolver or sand mill in the organic solvent and cellulose ester to disperse them before adding them to the dope.
- the amount of the UV absorber used is not uniform depending on the type of UV absorber, the operating conditions, etc., but when the dry film thickness of the polarizing plate protective film is 30 to 200 ⁇ m, the amount used is 0.5 to the polarizing plate protective film. Is preferably 10 to 10% by mass, and more preferably 0.6 to 4% by mass.
- Antioxidant are also referred to as deterioration inhibitors.
- a liquid crystal image display device or the like is placed in a high humidity and high temperature state, the cellulose ester film may be deteriorated.
- the antioxidant has a role of delaying or preventing the cellulose ester film from being decomposed by, for example, a residual solvent amount of halogen in the cellulose ester film or phosphoric acid of a phosphoric acid plasticizer. It is preferable to make it contain in a film.
- a hindered phenol compound is preferably used.
- 2,6-di-t-butyl-p-cresol, pentaerythrityl-tetrakis [3- (3,5-di- -T-butyl-4-hydroxyphenyl) propionate] triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3 -(3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino)- 1,3,5-triazine, 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], oct Decyl-3- (3,5-di-t-butyl-4-hydroxyphenyl
- 2,6-di-t-butyl-p-cresol, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], triethylene glycol-bis [3 -(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate] is preferred.
- hydrazine-based metal deactivators such as N, N′-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine and tris (2,4-di- A phosphorus processing stabilizer such as t-butylphenyl) phosphite may be used in combination.
- the amount of these compounds added is preferably 1 ppm to 1.0%, more preferably 10 to 1000 ppm in terms of mass ratio with respect to the cellulose derivative.
- Any useful acid scavenger can be used without limitation as long as it is a compound that reacts with an acid to inactivate the acid.
- the epoxy group described in US Pat. No. 4,137,201 is particularly useful.
- a compound having is preferred.
- Epoxy compounds as such acid scavengers are known in the art and are derived by condensation of various polyglycol diglycidyl ethers, particularly about 8 to 40 moles of ethylene oxide per mole of polyglycol.
- Glycol diglycidyl ethers of glycerol, metal epoxy compounds (such as those conventionally used in and with vinyl chloride polymer compositions), epoxidized ether condensation products, diphenols of bisphenol A Glycidyl ether (ie, 4,4'-dihydroxydiphenyldimethylmethane), epoxidized unsaturated fatty acid ester (especially an ester of an alkyl of about 2 to 2 carbon atoms of a fatty acid of 2 to 22 carbon atoms such as butyl Epoxy stearate And epoxidized vegetable oils and other unsaturated natural oils (sometimes these are epoxidized natural glycerides, which can be represented and exemplified by compositions of various epoxidized long chain fatty acid triglycerides and the like (eg, epoxidized soybean oil) Or unsaturated fatty acids, which generally contain 12 to 22 carbon atoms).
- EPON 815C can also be preferably used as
- acid scavengers that can be used other than the above, oxetane compounds, oxazoline compounds, alkaline earth metal organic acid salts and acetylacetonate complexes, and paragraphs 68 to 105 of JP-A-5-194788 Is included.
- the acid scavenger may be referred to as an acid scavenger, an acid scavenger, an acid catcher, etc., but in the present invention, they can be used without any difference due to their names.
- Fine particles In order to impart slipperiness, it is preferable to add fine particles.
- the primary average particle diameter of the fine particles is preferably 20 nm or less, more preferably 5 to 16 nm, and particularly preferably 5 to 12 nm.
- These fine particles preferably form secondary particles having a particle size of 0.1 to 5 ⁇ m and are contained in the retardation film, and the preferable average particle size is 0.1 to 2 ⁇ m, more preferably 0.2 to 0.6 ⁇ m.
- irregularities having a height of about 0.1 to 1.0 ⁇ m are formed on the film surface, thereby providing appropriate slipperiness to the film surface.
- the primary average particle size of the fine particles is measured by observing the particles with a transmission electron microscope (magnification 500,000 to 2,000,000 times), observing 100 particles, measuring the particle size, and using the average value, the primary value is measured. The average particle size was taken.
- the apparent specific gravity of the fine particles is preferably 70 g / liter or more, more preferably 90 to 200 g / liter, and particularly preferably 100 to 200 g / liter.
- a larger apparent specific gravity makes it possible to make a high-concentration dispersion, which improves haze and agglomerates, and is preferable when preparing a dope having a high solid content concentration as in the present invention.
- the amount of fine particles added to the cellulose ester is preferably 0.01 parts by weight to 5.0 parts by weight, more preferably 0.05 parts by weight to 1.0 parts by weight, and more preferably 0.1 parts by weight with respect to 100 parts by weight of the cellulose ester. Most preferred is from 0.5 to 0.5 parts by weight. The larger the added amount, the better the dynamic friction coefficient, and the smaller the added amount, the less aggregates.
- casting a dope containing fine particles so as to be in direct contact with the casting support is preferable because a film having high slip properties and low haze can be obtained.
- a functional thin film such as a hard coat layer or an antireflection layer may be provided.
- packaging is usually performed in order to protect the product from dirt, static electricity, and the like.
- the packaging material is not particularly limited as long as the above purpose can be achieved, but preferably does not hinder volatilization of the residual solvent from the film.
- Specific examples include polyethylene, polyester, polypropylene, nylon, polystyrene, paper, various non-woven fabrics, and the like.
- a fiber having a mesh cloth shape is more preferably used.
- the cellulose ester film used in the present invention can be preferably used regardless of whether it is a film produced by a solution casting method or a film produced by a melt casting method.
- the cellulose ester film used in the present invention is produced by dissolving a cellulose ester and an additive in a solvent to prepare a dope, casting on an endless metal support that moves the dope indefinitely.
- the concentration of cellulose ester in the dope is preferably higher because the drying load after casting on the metal support can be reduced. However, if the concentration of cellulose ester is too high, the load during filtration increases and the filtration accuracy is poor. Become.
- the concentration that achieves both of these is preferably 10 to 35% by mass, and more preferably 15 to 25% by mass.
- the solvent used in the dope may be used alone or in combination of two or more, but it is preferable to use a mixture of a good solvent and a poor solvent of cellulose ester in terms of production efficiency, and there are many good solvents. This is preferable from the viewpoint of the solubility of the cellulose ester.
- a preferable range of the mixing ratio of the good solvent and the poor solvent is 70 to 98% by mass for the good solvent and 2 to 30% by mass for the poor solvent.
- the good solvent used in the present invention is not particularly limited, and examples thereof include organic halogen compounds such as methylene chloride, dioxolanes, acetone, methyl acetate, and methyl acetoacetate. Particularly preferred is methylene chloride or methyl acetate.
- the poor solvent used in the present invention is not particularly limited, but for example, methanol, ethanol, n-butanol, cyclohexane, cyclohexanone and the like are preferably used.
- the dope preferably contains 0.01 to 2% by mass of water.
- the solvent used for dissolving the cellulose ester is used by collecting the solvent removed from the film by drying in the film-forming process and reusing it.
- the recovery solvent may contain trace amounts of additives added to the cellulose ester, such as plasticizers, UV absorbers, polymers, monomer components, etc., but even if these are included, they are preferably reused. Can be purified and reused if necessary.
- additives added to the cellulose ester such as plasticizers, UV absorbers, polymers, monomer components, etc., but even if these are included, they are preferably reused. Can be purified and reused if necessary.
- a general method can be used. When heating and pressurization are combined, it is possible to heat above the boiling point at normal pressure.
- a method in which a cellulose ester is mixed with a poor solvent and wetted or swollen, and then a good solvent is added and dissolved is also preferably used.
- Pressurization may be performed by a method of injecting an inert gas such as nitrogen gas or a method of increasing the vapor pressure of the solvent by heating. Heating is preferably performed from the outside.
- a jacket type is preferable because temperature control is easy.
- the heating temperature with the addition of the solvent is preferably higher from the viewpoint of the solubility of the cellulose ester, but if the heating temperature is too high, the required pressure increases and the productivity deteriorates.
- the preferred heating temperature is 45 to 120 ° C, more preferably 60 to 110 ° C, and still more preferably 70 ° C to 105 ° C.
- the pressure is adjusted so that the solvent does not boil at the set temperature.
- a cooling dissolution method is also preferably used, whereby the cellulose ester can be dissolved in a solvent such as methyl acetate.
- the cellulose ester solution is filtered using an appropriate filter medium such as filter paper.
- an appropriate filter medium such as filter paper.
- the filter medium it is preferable that the absolute filtration accuracy is small in order to remove insoluble matters and the like, but there is a problem that the filter medium is likely to be clogged if the absolute filtration accuracy is too small.
- a filter medium with an absolute filtration accuracy of 0.008 mm or less is preferable, a filter medium with 0.001 to 0.008 mm is more preferable, and a filter medium with 0.003 to 0.006 mm is still more preferable.
- the material of the filter medium there are no particular restrictions on the material of the filter medium, and ordinary filter media can be used. However, plastic filter media such as polypropylene and Teflon (registered trademark), and metal filter media such as stainless steel do not drop off fibers. preferable.
- Bright spot foreign matter means that when two polarizing plates are placed in a crossed Nicol state, an optical film or the like is placed between them, light is applied from one polarizing plate side, and observation is performed from the other polarizing plate side. It is a point (foreign matter) where light from the opposite side appears to leak, and the number of bright spots having a diameter of 0.01 mm or more is preferably 200 / cm 2 or less.
- it is 100 pieces / cm 2 or less, still more preferably 50 pieces / m 2 or less, still more preferably 0 to 10 pieces / cm 2 . Further, it is preferable that the number of bright spots of 0.01 mm or less is small.
- the dope can be filtered by a normal method, but the method of filtering while heating at a temperature not lower than the boiling point of the solvent at normal pressure and in a range where the solvent does not boil under pressure is the filtration pressure before and after filtration.
- the increase in the difference (referred to as differential pressure) is small and preferable.
- the preferred temperature is 45 to 120 ° C, more preferably 45 to 70 ° C, and still more preferably 45 to 55 ° C.
- the filtration pressure is preferably 1.6 MPa or less, more preferably 1.2 MPa or less, and further preferably 1.0 MPa or less.
- the metal support in the casting process is preferably a mirror-finished surface, and a stainless steel belt or a drum whose surface is plated with a casting is preferably used as the metal support.
- the cast width can be 1 ⁇ 4m.
- the surface temperature of the metal support in the casting step is ⁇ 50 ° C. to less than the boiling point of the solvent, and a higher temperature is preferable because the web drying speed can be increased. May deteriorate.
- the preferred support temperature is 0 to 55 ° C, more preferably 25 to 50 ° C.
- the method for controlling the temperature of the metal support is not particularly limited, but there are a method of blowing hot air or cold air, and a method of contacting hot water with the back side of the metal support. It is preferable to use warm water because heat transfer is performed efficiently, so that the time until the temperature of the metal support becomes constant is short. When warm air is used, wind at a temperature higher than the target temperature may be used.
- the amount of residual solvent when peeling the web from the metal support is preferably 10 to 150% by mass, more preferably 20 to 40% by mass or 60 to 130% by mass. Particularly preferred is 20 to 30% by mass or 70 to 120% by mass.
- the amount of residual solvent is defined by the following formula.
- Residual solvent amount (% by mass) ⁇ (MN) / N ⁇ ⁇ 100 M is the mass of a sample collected during or after the production of the web or film, and N is the mass after heating M at 115 ° C. for 1 hour.
- the web is peeled off from the metal support, and further dried, and the residual solvent amount is preferably 1% by mass or less, more preferably 0.1% by mass or less, Particularly preferred is 0 to 0.01% by mass or less.
- a roll drying method (a method in which webs are alternately passed through a plurality of rolls arranged above and below) and a method in which the web is dried while being conveyed by a tenter method are employed.
- the cellulose ester film used in the present invention it is particularly preferable to perform stretching in the width direction (lateral direction) by a tenter method in which both ends of the web are held with clips or the like. Peeling is preferably performed at a peeling tension of 300 N / m or less.
- the means for drying the web is not particularly limited, and can be generally performed with hot air, infrared rays, a heating roll, microwave, or the like, but is preferably performed with hot air in terms of simplicity.
- drying temperature in the web drying process is increased stepwise from 40 to 200 ° C.
- the film thickness of the cellulose ester film is not particularly limited, but 10 to 200 ⁇ m is used.
- the film thickness is particularly preferably 10 to 100 ⁇ m. More preferably, it is 20 to 60 ⁇ m.
- a cellulose ester film having a width of 1 to 4 m is used. Particularly, those having a width of 1.4 to 4 m are preferably used, and particularly preferably 1.6 to 3 m. If it exceeds 4 m, conveyance becomes difficult.
- the retardation value can be changed by lowering or increasing the tension in the longitudinal direction.
- biaxial stretching or uniaxial stretching sequentially or simultaneously with respect to the longitudinal direction (film forming direction) of the film and the direction orthogonal to the longitudinal direction of the film, that is, the width direction.
- the draw ratios in the biaxial directions perpendicular to each other are preferably in the range of 0.8 to 1.5 times in the casting direction and 1.1 to 2.5 times in the width direction, respectively. It is preferable to carry out in the range of 0.8 to 1.0 times in the direction and 1.2 to 2.0 times in the width direction.
- the stretching temperature is preferably from 120 to 200 ° C, more preferably from 150 to 200 ° C, and further preferably from 150 ° C to 190 ° C.
- the residual solvent in the film is preferably 20 to 0%, more preferably 15 to 0%.
- the residual solvent is stretched by 11% at 155 ° C., or the residual solvent is stretched by 2% at 155 ° C. Alternatively, it is preferable that the residual solvent is stretched at 11% at 160 ° C, or the residual solvent is stretched at less than 1% at 160 ° C.
- the method of stretching the web For example, a method in which a circumferential speed difference is applied to a plurality of rolls, and the roll circumferential speed difference is used to stretch the rolls in the vertical direction. Both ends of the web are fixed with clips and pins, and the interval between the clips and pins is increased in the traveling direction And a method of stretching in the vertical direction, a method of stretching in the horizontal direction and stretching in the horizontal direction, a method of stretching in the vertical and horizontal directions and stretching in both the vertical and horizontal directions, and the like. Of course, these methods may be used in combination.
- a tenter it may be a pin tenter or a clip tenter.
- the slow axis or the fast axis of the cellulose ester film used in the present invention exists in the film plane, and ⁇ 1 is preferably ⁇ 1 ° or more and + 1 ° or less when the angle formed with the film forming direction is ⁇ 1. It is more preferably ⁇ 0.5 ° or more and + 0.5 ° or less, and further preferably ⁇ 0.1 ° or more and + 0.1 ° or less.
- This ⁇ 1 can be defined as an orientation angle, and ⁇ 1 can be measured using an automatic birefringence meter KOBRA-21ADH (Oji Scientific Instruments).
- ⁇ 1 satisfying the above relationship can contribute to obtaining high luminance in a display image, suppressing or preventing light leakage, and can contribute to obtaining faithful color reproduction in a color liquid crystal display device.
- the moisture permeability of the cellulose ester film used in the present invention 40 ° C., preferably 300 ⁇ 1800g / m 2 ⁇ 24h at 90% RH, preferably more 400 ⁇ 1500g / m 2 ⁇ 24h , 40 ⁇ 1300g / m 2 ⁇ 24h is particularly preferred.
- the moisture permeability can be measured according to the method described in JIS Z 0208.
- the breaking elongation is preferably 5 to 80%, more preferably 10 to 50%.
- the visible light transmittance is preferably 90% or more, and more preferably 93% or more.
- the in-plane retardation value (Ro) and the retardation value (Rt) in the thickness direction of the cellulose ester film used in the present invention are 0 ⁇ Ro and Rt ⁇ 70 nm when used as a polarizer protective film. preferable. More preferably, 0 ⁇ Ro ⁇ 30 nm and 0 ⁇ Rt ⁇ 50 nm, and more preferably 0 ⁇ Ro ⁇ 10 nm and 0 ⁇ Rt ⁇ 30 nm.
- the cellulose ester film used in the present invention is preferably used as a retardation film.
- the variation of Rt and the width of the distribution are preferably less than ⁇ 50%, preferably less than ⁇ 30%, and preferably less than ⁇ 20%. Further, it is preferably less than ⁇ 15%, preferably less than ⁇ 10%, preferably less than ⁇ 5%, particularly preferably less than ⁇ 1%. Most preferably, there is no variation in Rt.
- the retardation values Ro and Rt can be obtained by the following equations.
- the thickness (n m) of d is the film
- the refractive index n x maximum refractive index in the plane of the film, also referred to as a slow axis direction of the refractive index
- n y slow axis in the film plane N z (the refractive index of the film in the thickness direction).
- Retardation values (Ro) and (Rt) can be measured using an automatic birefringence meter. For example, it can be obtained at a wavelength of 590 nm under an environment of 23 ° C. and 55% RH using KOBRA-21ADH (Oji Scientific Instruments).
- the polarizing plate of the present invention is a polarizing plate in which both sides of a polarizer are sandwiched between protective films, and at least one of the protective films is a protective film that is hydrophilized by either plasma treatment or corona treatment. It is characterized by.
- plasma treatment or corona treatment various conventionally known methods can be employed. In the present invention, it is particularly preferable to employ plasma treatment.
- Examples of the plasma treatment applicable to the present invention include JP-A-11-133205, JP-A-2000-185362, JP-A-11-61406, JP-A-2000-147209, and JP-A-2000-121804.
- the disclosed technology can be mentioned.
- a gas is supplied to the discharge space (between the counter electrodes) at atmospheric pressure or in the vicinity thereof, a high-frequency voltage is applied to the discharge space, and the gas is excited to form a plasma state.
- the surface treatment is performed by exposing the polarizing plate protective film to this excited plasma state gas, and this method is referred to as an atmospheric pressure plasma treatment method (hereinafter sometimes referred to as plasma treatment).
- the plasma irradiation includes a case where the surface of the polarizing plate protective film is directly exposed to the plasma treatment, and a case where excited active species formed by plasma discharge are sprayed on the surface of the polarizing plate protective film.
- the high frequency voltage applied to the discharge space formed between the counter electrodes may be a high frequency of one frequency, or may be a high frequency of two or more frequencies.
- the high frequency as used in this invention means what has a frequency of at least 0.5 kHz or more.
- the frequency of the high frequency power source is preferably 50 kHz or more and 27 MHz or less.
- the atmospheric pressure plasma treatment is performed under atmospheric pressure or a pressure in the vicinity thereof, and the atmospheric pressure or the pressure in the vicinity thereof is about 20 to 110 kPa, so that the good effects described in the present invention can be obtained. Is preferably 93 to 104 kPa.
- various gases such as nitrogen, hydrogen, argon, helium, carbon monoxide, and ammonia can be used as the gas supplied between the counter electrodes (discharge space). From the viewpoint of cost, it is preferable to use 50% by volume or more of nitrogen gas. preferable.
- the atmospheric pressure plasma treatment according to the present invention is a surface treatment, but may include an excitation gas excited by a high frequency voltage and a thin film forming gas that receives the energy and forms a thin film in a plasma state or an excited state.
- the difference is that there are two high-frequency power supplies, a filter attached to it, and a high-frequency voltage is applied from both electrodes of the counter electrode.
- one of the counter electrodes is a ground electrode, and the other is an application electrode.
- a high-frequency power source is connected to the application electrode, and the ground is grounded to the ground electrode. Has been.
- the plasma processing apparatus (atmospheric pressure plasma processing apparatus) of each of the 1 frequency high frequency voltage application system and the 2 frequency high frequency voltage application system will be described with reference to the drawings.
- FIG. 1 is a schematic view showing an example of a plasma processing apparatus of a single frequency high frequency voltage application system useful for the present invention.
- a counter electrode is formed by an application electrode (rectangular tube electrode) 136 for applying a high-frequency voltage inside the plasma discharge vessel 130 and a roll-type ground electrode 135 around which the transparent resin film F is wound. Any number of application electrodes 136 may be arranged.
- the gas G is supplied from the gas supply port 152 of the plasma discharge vessel 10, passes through a mesh for uniformizing the gas G, passes between the application electrodes 136 and along the inner wall of the application electrode and the plasma discharge vessel 131, and The discharge space 13 is filled with the gas G.
- a high frequency voltage is applied to the application electrode 136 by the high frequency power source 21, the transparent resin film F is exposed to the gas G excited in the discharge space 132, and a thin film is formed on the transparent resin film F.
- the frequency of the applied high frequency voltage is in the range of 50 kHz to 150 MHz. In the present invention, the frequency of the high frequency power source is preferably 50 kHz or more and 27 MHz or less.
- the electrode is heated or cooled via the pipe from the electrode temperature adjusting means 160.
- the physical properties and composition of the resulting thin film may change, and it is desirable to appropriately control this.
- the temperature control medium an insulating material such as distilled water or oil is preferably used.
- it is desired to uniformly adjust the temperature inside the electrode so that the temperature unevenness of the base material in the width direction or the longitudinal direction does not occur as much as possible.
- FIG. 2 is a schematic view showing another example of a plasma processing apparatus of a two-frequency high-frequency voltage application system useful for the present invention.
- the transparent resin film F is subjected to plasma treatment between the opposing electrodes (discharge space) 132 between the roll electrode (first electrode) 135 and the square tube electrode group (second electrode) 136. .
- the roll electrode (first electrode) 135 In the discharge space (between the counter electrodes) 132 between the roll electrode (first electrode) 135 and the rectangular tube electrode group (second electrode) 136, the roll electrode (first electrode) 135 has a frequency from the first electrode 141.
- the high-frequency voltage V 1 is applied to ⁇ 1
- the high-frequency voltage V 2 having the frequency ⁇ 2 from the second power source 142 is applied to the rectangular tube electrode group (second electrode) 136.
- a first filter 143 is installed between the roll electrode (first electrode) 135 and the first power supply 141 so that the current from the first power supply 141 flows toward the roll electrode (first electrode) 135.
- the first filter is designed to make it difficult for the current from the first power source 141 to pass through and to easily pass the current from the second power source 142.
- a second filter 144 is installed between the square tube electrode group (second electrode) 136 and the second power source 142 so that the current from the second power source flows toward the second electrode,
- the second filter 144 is designed to make it difficult for the current from the second power source 142 to pass through and to easily pass the current from the first power source 141.
- being difficult to pass means that it preferably passes only 20% or less of the current, more preferably 10% or less.
- being easy to pass means preferably passing 80% or more of the current, more preferably 90% or more.
- any filter having the above properties can be used without limitation.
- a capacitor of several tens to several tens of thousands of pF or a coil of about several ⁇ H can be used depending on the frequency of the second power source.
- a coil of 10 ⁇ H or more is used according to the frequency of the first power supply, and it can be used as a filter by grounding through these coils or capacitors.
- the roll electrode 135 may be the second electrode, and the rectangular tube electrode group 136 may be the first electrode.
- the first power source is connected to the first electrode, and the second power source is connected to the second electrode.
- the first power source only needs to have the capability of applying a higher frequency voltage (V 1 > V 2 ) than the second power source.
- the frequency should just have the capability which becomes (omega) 1 ⁇ (omega) 2 .
- the gas G generated by the gas supply device 151 of the gas supply means 150 is introduced into the plasma processing vessel 131 from the air supply port 152 while controlling the flow rate.
- the discharge space 132 and the plasma processing vessel 131 are filled with the gas G.
- the transparent resin film F is unwound from the original winding and is conveyed by being unwound or is conveyed from the previous process and is accompanied by the transparent resin film by the nip roll 165 via the guide roll 164 , And while being in contact with the roll electrode 135, it is transferred to and from the rectangular tube electrode group 136, and both the roll electrode (first electrode) 135 and the rectangular tube electrode group (second electrode) 136 are transferred.
- a voltage is applied from above to generate discharge plasma between the counter electrodes (discharge space) 132.
- the transparent resin film F is irradiated with plasma gas while being wound while being in contact with the roll electrode 135.
- the transparent resin film F passes through the nip roll 166 and the guide roll 167, and is taken up by a winder (not shown) or transferred to the next process.
- the treated exhaust gas G ′ is discharged from the exhaust port 153.
- a medium whose temperature is adjusted by the electrode temperature adjusting means 160 is supplied by the liquid feed pump P. It sends to both electrodes through the piping 161, and temperature is adjusted from the inside of an electrode.
- Reference numerals 165 and 166 denote partition plates that partition the plasma processing vessel 131 from the outside.
- the high-frequency voltage to be applied may be an intermittent pulse wave or a continuous sine wave, and is not limited to the applied voltage waveform. Sine waves are preferred for forming the thin film.
- the frequency of the high frequency voltage applied to the first electrode is preferably 1 kHz to 200 kHz, and the frequency of the high frequency voltage applied to the second electrode is preferably 800 kHz or more.
- the power density at that time is preferably 1 to 50 W / cm 2 (where the denominator cm 2 is the area where discharge occurs), more preferably 1.2 to 30 W / cm 2 .
- Examples of the high-frequency power source useful for the plasma processing apparatus used in the present invention include 100 kHz * (manufactured by HEIDEN Laboratory), 200 kHz, 800 kHz, 2 MHz, 13.56 MHz, 27 MHz, and 150 MHz (all manufactured by Pearl Industry). it can.
- * mark is HEIDEN Laboratory impulse high frequency power supply (100 kHz in continuous mode).
- FIG. 3 is a perspective view showing an example of the structure of the conductive metallic base material of the roll electrode shown in the figure and the dielectric material coated thereon.
- a roll electrode 35a has a conductive metallic base material 35A and a dielectric 35B coated thereon.
- the inside is a hollow jacket, and the temperature is adjusted.
- FIG. 4 is a perspective view showing an example of the structure of the conductive metallic base material of the rectangular tube type electrode shown in FIGS. 1 and 2 and the dielectric material coated thereon.
- a rectangular tube electrode 36a has a coating of a dielectric 36B similar to that of FIG. 3 on a conductive metallic base material 36A, and the structure of the electrode is a metallic pipe. , It becomes a jacket so that the temperature can be adjusted during discharge.
- the number of the rectangular tube-shaped electrodes is set in plural along a circumference larger than the circumference of the roll electrode, and the discharge area of the electrodes is a full-square tube electrode surface facing the roll electrode 35. It is represented by the sum of the areas.
- the rectangular tube electrode 36a shown in FIG. 4 may be a cylindrical electrode, but the rectangular tube electrode has an effect of expanding the discharge range (discharge area) as compared with the cylindrical electrode, and thus is preferably used in the present invention. .
- the roll electrode 35a and the rectangular tube type electrode 36a are formed by spraying ceramics as dielectrics 35B and 36B on conductive metallic base materials 35A and 36A, respectively, and then sealing the inorganic compound. Is subjected to a sealing treatment.
- the ceramic dielectric may be covered by about 1 mm with a single wall.
- As the ceramic material used for thermal spraying alumina, silicon nitride, or the like is preferably used. Among these, alumina is particularly preferable because it is easily processed.
- the dielectric layer may be a lining-processed dielectric provided with an inorganic material by glass lining.
- a metal such as titanium or titanium alloy, silver, platinum, stainless steel, aluminum, or iron, a composite material of iron and ceramics, or a composite material of aluminum and ceramics is used.
- titanium or a titanium alloy is especially preferable for the reason mentioned below.
- the distance between the two electrodes is determined in consideration of the thickness of the dielectric provided on the conductive metallic base material, the magnitude of the applied voltage, the purpose of using plasma, etc.
- the plasma processing container 10 or 31 is preferably a processing container made of Pyrex (registered trademark) glass or the like, but may be made of metal as long as it can be insulated from the electrodes.
- polyimide resin or the like may be attached to the inner surface of an aluminum or stainless steel frame, and the metal frame may be thermally sprayed to obtain insulation.
- FIG. 1 it is preferable to cover both side surfaces (up to the vicinity of the base material surface) of both parallel electrodes with an object made of the above material.
- the maximum height (Rmax) of the surface roughness defined by JIS B 0601 on the side in contact with at least the base material of the electrode may be adjusted to 1 ⁇ m or less.
- the maximum value of the surface roughness is more preferably 0.8 ⁇ m or less, and particularly preferably adjusted to 0.7 ⁇ m or less.
- the polishing finish of the dielectric surface is preferably performed at least on the dielectric in contact with the substrate. Furthermore, the larger the centerline average surface roughness (Ra) defined in JIS B 0601, the larger the surface area and the better the adhesion, but the front contrast in the liquid crystal display device due to light scattering is prevented from decreasing. Therefore, the thickness is preferably 2.0 to 10.0 nm, more preferably 2.0 to 5.0 nm.
- the heat-resistant temperature is 100 ° C. or higher. More preferably, it is 120 degreeC or more, Most preferably, it is 150 degreeC or more. The upper limit is 500 ° C.
- the heat-resistant temperature refers to the highest temperature that can withstand normal discharge without breakdown. Such heat-resistant temperature can be applied by using the above-mentioned ceramic spraying or dielectric materials provided by layered glass linings with different amounts of bubbles, or within the range of the difference in linear thermal expansion coefficient between the metallic base material and the dielectric material below. This can be achieved by appropriately combining means for appropriately selecting the materials.
- the power applied between the opposing electrodes supplies a power density of 1 to 50 W / cm 2 to the second electrode to excite the discharge gas to generate plasma. It is preferably 1.2 to 30 W / cm 2 .
- a continuous sine wave continuous oscillation mode called a continuous mode or an intermittent oscillation mode that performs ON / OFF intermittently called a pulse mode may be adopted, but at least On the second electrode side, the continuous sine wave is preferable because it is denser and can perform high-quality plasma processing.
- the discharge condition in the present invention is that a high-frequency voltage is applied to the discharge space between the opposing first electrode and second electrode, and the high-frequency voltage is a voltage component of the first frequency ⁇ 1 and the first frequency ⁇ . It is preferable to have at least a component obtained by superimposing a voltage component of the second frequency ⁇ 2 higher than 1 .
- the high-frequency voltage is a component obtained by superimposing the voltage component of the first frequency ⁇ 1 and the voltage component of the second frequency ⁇ 2 higher than the first frequency ⁇ 1 , and the waveform thereof is a sign of the frequency ⁇ 1 .
- the waveform is a sine wave of ⁇ 1 in which a sine wave of higher frequency ⁇ 2 is superimposed on the wave. It is not limited to a waveform in which a sine wave is superimposed, and both pulse waves may be used, one may be a sine wave and the other may be a pulse wave. Furthermore, it may have a third voltage component. However, in the present invention, as in the single-frequency high-frequency voltage application method, a continuous sine wave at least on the second electrode side can provide a denser and better quality film.
- the discharge start voltage refers to the lowest voltage that can cause discharge in the discharge space (electrode configuration, etc.) and reaction conditions (gas conditions, etc.) used in actual plasma processing.
- the discharge start voltage varies somewhat depending on the gas type supplied to the discharge space, the dielectric type of the electrode, and the like, but may be considered to be substantially the same as the discharge start voltage of the discharge gas alone.
- a specific method of applying a high-frequency voltage to the discharge space is as follows: a first power supply that applies a first high-frequency voltage having a frequency ⁇ 1 and a voltage V 1 to the first electrode constituting the counter electrode. And a second power supply for applying a second high-frequency voltage having a frequency ⁇ 2 and a voltage V 2 is connected to the second electrode.
- the first power source of the plasma processing apparatus used in the present invention has an ability to apply a higher high-frequency voltage than the second power source.
- a high frequency voltage is applied between the first electrode and the second electrode facing each other, and the high frequency voltage is applied to the first high frequency voltage V 1 and the second high frequency voltage.
- V 1 ⁇ IV> V 2 or V 1 > IV ⁇ V 2 is satisfied. More preferably, V 1 >IV> V 2 is satisfied.
- the definition of the high frequency and the discharge start voltage, and the specific method of applying the high frequency voltage between the counter electrodes (discharge space) are the same as those described above.
- the high frequency voltage (applied voltage) and the discharge start voltage in the present invention are those measured by the following method.
- Measuring method of high frequency voltages V 1 and V 2 (unit: kV / mm): A high-frequency probe (P6015A) for each electrode part is installed, and the high-frequency probe is connected to an oscilloscope (Tektronix, TDS3012B) to measure the voltage.
- Measuring method of discharge start voltage IV (unit: kV / mm): A discharge gas is supplied between the electrodes, the voltage between the electrodes is increased, and a voltage at which discharge starts is defined as a discharge start voltage IV.
- the measuring instrument is the same as the above high-frequency voltage measurement.
- a discharge gas having a high discharge start voltage such as nitrogen gas can start the discharge gas and maintain a high density and stable plasma state.
- a high-performance thin film can be formed.
- the discharge start voltage IV is about 3.7 kV / mm. Therefore, in the above relationship, the first high-frequency voltage is V 1 ⁇ 3.7 kV / mm. As a result, the nitrogen gas can be excited to be in a plasma state.
- the discharge gas there are noble gases such as nitrogen, helium, argon, air, hydrogen, etc., and these may be used alone as a discharge gas or mixed, but using nitrogen gas, Compared with the case where a rare gas such as helium or argon is used, it is particularly preferable because high economic efficiency of the discharge gas can be obtained.
- the amount of discharge gas is preferably 70 to 100% by volume based on the total amount of gas supplied to the discharge space.
- the high-frequency power source installed in the plasma processing apparatus (atmospheric pressure plasma processing apparatus) used in the present invention is the same as that described above, but the first power source (high-frequency power source) and the second power source (high-frequency power source) depend on the frequency. It is divided as follows.
- High frequency power supply code Manufacturer Frequency A1 Shinko Electric 3kHz A2 Shinko Electric 5kHz A3 Kasuga Electric 15kHz A4 Shinko Electric 50kHz A5 HEIDEN Laboratory 100kHz * A6 Pearl Industry 200kHz In addition, * mark is HEIDEN Laboratory impulse high frequency power supply (100 kHz in continuous mode).
- High frequency power supply symbol Manufacturer Frequency B1 Pearl Industry 800kHz B2 Pearl Industry 2MHz B3 Pearl Industry 13.56MHz B4 Pearl Industry 27MHz B5 Pearl Industry 150MHz And the like, and any of them can be preferably used.
- At least one of the counter electrodes has a film thickness control unit, and a gas supply unit that supplies a discharge gas is provided between the counter electrodes. Furthermore, it is preferable to have an electrode temperature control means for controlling the temperature of the electrode.
- corona treatment (also referred to as “corona discharge treatment”) is the most well-known method, and any conventionally known method such as Japanese Patent Publication No. 48-5043 and 47-47. No. 51905, JP-A-47-28067, JP-A-49-83767, JP-A-51-41770, JP-A-51-131576, and the like.
- a corona treatment machine used for corona treatment various commercially available corona treatment machines currently used as means for surface modification of plastic films and the like can be applied. Among them, a multi-knife electrode manufactured by SOFTAL is used.
- the corona treatment machine has a number of electrodes, and air is sent between the electrodes, which can prevent the heating of the film and remove small molecules that appear on the film surface. Since it is very high and high corona treatment is possible, it is a corona treatment machine particularly useful for the present invention.
- the conditions for corona treatment vary depending on the type of film used, the type of pressure-sensitive adhesive, the type of corona treatment machine used, etc., but the energy density per treatment is about 20 to 400 W ⁇ min / m 2. preferable.
- the treatment with low energy as much as possible as compared with the treatment with high energy suppresses deterioration of the protective film to be treated, bleeding to the surface of the filler in the protective film, etc., and is effective in improving the adhesive strength. If the single treatment is insufficient, the adhesive strength can be further improved by carrying out multiple treatments twice or more.
- the polarizing plate using the hydrophilically treated polarizing plate protective film of the present invention can be used for a liquid crystal display device.
- the polarizing plate of the present invention is a polarizing plate in which the polarizing plate protective film according to the present invention is bonded to at least one surface of a polarizer.
- the polarizing plate according to the present invention is bonded to at least one liquid crystal cell surface via an adhesive layer.
- the polarizing plate of the present invention can be produced by a general method. Using the fully saponified polyvinyl alcohol aqueous solution on at least one surface of the polarizer prepared by subjecting the polarizer side of the protective film according to the present invention to the hydrophilic treatment described above and immersing and stretching in an iodine solution. It is preferable to bond them together.
- cellulose ester films for example, Konica Minoltack KC8UX, KC5UX, KC8UCR3, KC8UCR4, KC8UCR5, KC8UY, KC4UY, KC4UE, KC8UE, KC8UY-HA, KC8UX-RHA, KC8UX-RHA, KC8UX KC4UXW-RHA-NC, manufactured by Konica Minolta Opto Co., Ltd.
- cellulose ester films for example, Konica Minoltack KC8UX, KC5UX, KC8UCR3, KC8UCR4, KC8UCR5, KC8UY, KC4UY, KC4UE, KC8UE, KC8UY-HA, KC8UX-RHA, KC8UX-RHA, KC8UX KC4UXW-RHA-NC, manufactured by Konica Minolta Opto Co., Ltd.
- the polarizing plate protective film used on the surface side of the liquid crystal display device preferably has an antireflection layer, an antistatic layer, an antifouling layer, and a backcoat layer.
- a polarizer which is a main component of a polarizing plate, is an element that allows only light of a plane of polarization in a certain direction to pass.
- a typical polarizer currently known is a polyvinyl alcohol-based polarizing film, which is polyvinyl alcohol.
- iodine is dyed on a system film and one in which dichroic dye is dyed.
- the polarizer is formed by forming a polyvinyl alcohol aqueous solution into a film and dyeing the film by uniaxial stretching or dyeing or uniaxially stretching, and then performing a durability treatment with a boron compound.
- the film thickness of the polarizer is preferably 5 to 30 ⁇ m, particularly preferably 10 to 20 ⁇ m.
- the ethylene unit content described in JP-A-2003-248123, JP-A-2003-342322, etc. is 1 to 4 mol%
- the degree of polymerization is 2000 to 4000
- the degree of saponification is 99.0 to 99.99 mol%.
- the ethylene-modified polyvinyl alcohol is also preferably used.
- an ethylene-modified polyvinyl alcohol film having a hot water cutting temperature of 66 to 73 ° C. is preferably used.
- a polarizer using this ethylene-modified polyvinyl alcohol film is excellent in polarization performance and durability performance and has few color spots, and is particularly preferably used for a large liquid crystal display device.
- the polarizer obtained as described above is usually used as a polarizing plate with a protective film bonded to both sides or one side.
- the adhesive used for pasting include a PVA-based adhesive and a urethane-based adhesive. Among them, a PVA-based adhesive is preferably used.
- the present invention The polarizing plate of the present invention can be used for liquid crystal display devices of various drive systems such as STN, TN, OCB, HAN, VA (MVA, PVA), IPS, OCB.
- a VA (MVA, PVA) type liquid crystal display device is preferable.
- liquid crystal display device with a 30-inch screen or more can obtain a liquid crystal display device with excellent visibility such as uneven coloring and front contrast with little environmental fluctuation, reduced light leakage.
- ⁇ Fine particle additive solution CE-1 (Daicel Diacetyl Cellulose: L20) was added to the dissolution tank containing methylene chloride and heated to completely dissolve, and this was then added to Azumi Filter Paper No. 3 manufactured by Azumi Filter Paper Co., Ltd. Filtered using 244. The fine particle dispersion was slowly added thereto while sufficiently stirring the filtered cellulose ester solution. Further, the particles were dispersed by an attritor so that the secondary particles had a predetermined particle size. This was filtered through Finemet NF manufactured by Nippon Seisen Co., Ltd. to prepare a fine particle additive solution.
- CE-1 Disicel Diacetyl Cellulose: L20
- a cellulose ester film 101 of the present invention having a film thickness of 40 ⁇ m and a knurling of 0.5 m and a width of 1 cm at the end and a height of 8 ⁇ m was produced.
- a cellulose ester film 105 was produced in the same manner except that the cellulose ester used was CE-2 (Ca394-60S from Eastman Chemical Co.) and the additives A and B were changed as shown in Table 1.
- a cellulose ester film 106 was produced in the same manner except that the cellulose ester used was changed to CE-3 (Ca398-30, Eastman Chemical Co.) and the additives A and B were changed as shown in Table 1.
- a cellulose ester film 108 was prepared in the same manner except that the cellulose ester used was CE-5 (LM 80 manufactured by Daicel) and the additives A and B were changed as shown in Table 1.
- a cellulose ester film 109 was produced in the same manner except that the cellulose ester used was CE-6 (LT35 manufactured by Daicel) and the additives A and B were changed as shown in Table 1.
- cellulose ester film 110 was produced in the same manner except that the cellulose ester used was CE-7 (CAP141-20 from Eastman Chemical Co.) and the additives A and B were changed as shown in Table 1.
- cellulose ester film 111 was produced in the same manner except that it was changed.
- TPP Triphenyl phosphate BDP: Biphenyl diphenyl phosphate PETB: Pentaerythritol tetrabenzoate
- EPEG Ethylphthalyl ethyl glycolate
- a polyvinyl alcohol film having a thickness of 120 ⁇ m was uniaxially stretched (temperature: 110 ° C., stretch ratio: 5 times). This was immersed in an aqueous solution consisting of 0.075 g of iodine, 5 g of potassium iodide and 100 g of water for 60 seconds, and then immersed in an aqueous solution of 68 ° C. consisting of 6 g of potassium iodide, 7.5 g of boric acid and 100 g of water. This was washed with water and dried to obtain a polarizer.
- a polarizer, the cellulose ester films 101 to 111, and Konica Minolta Op KC8UY manufactured by Konica Minolta Opto Co., Ltd. were bonded to the back side as a polarizing plate protective film to produce a polarizing plate.
- Step 1 The cellulose ester films 101 to 111 were hydrophilized under the conditions shown in Tables 2 to 4.
- Step 2 The polarizer was immersed in a polyvinyl alcohol adhesive tank having a solid content of 2% by mass for 1 to 2 seconds.
- Step 3 Excess adhesive adhered to the polarizer in Step 2 was gently wiped off, and this was placed on the cellulose ester film hydrophilized in Step 1 and further placed on the back side cellulose ester film.
- Step 4 The cellulose ester films 101 to 111 laminated in Step 3 were bonded together with the polarizer and the back side cellulose ester film at a pressure of 20 to 30 N / cm 2 and a conveying speed of about 2 m / min.
- Step 5 A sample obtained by bonding the polarizer prepared in Step 4 to the cellulose ester films 101 to 111 and the back side cellulose ester film in a drier at 80 ° C. was dried for 2 minutes to prepare polarizing plates 201 to 229. .
- a liquid crystal panel for front contrast measurement was produced as follows, and the characteristics as a liquid crystal display device were evaluated.
- the polarizing plates on both surfaces of the Sony 40-type display KLV-40V2500 previously bonded were peeled off, and the prepared polarizing plates 201 to 229 were bonded to both surfaces of the glass surface of the liquid crystal cell, respectively.
- the direction of bonding of the polarizing plate is such that the surface of the cellulose ester film of the present invention is on the liquid crystal cell side, and the absorption axis is in the same direction as the polarizing plate previously bonded.
- each of the liquid crystal display devices was manufactured.
- d is the thickness of the film (nm), (refractive index in a slow axis direction) refractive index n x, n y (perpendicular direction refractive index in the slow axis in the film plane), n z (thickness The refractive index of the film in the vertical direction).
- Retardation values Ro and Rt were determined using an automatic birefringence meter KOBRA-21ADH (Oji Scientific Instruments) at 23 ° C. and 55% RH at a wavelength of 590 nm.
- the blank haze 1 of a measuring instrument other than a film is measured.
- the haze 2 including the sample is measured by the following procedure. 4).
- Glycerin (0.05 ml) is dropped on the slide glass (see FIG. 1A). 5. Place the sample film to be measured on it so that no air bubbles enter (see Fig. 1 (b)). 6).
- Glycerin (0.05 ml) is dropped on the sample film (see FIG. 1 (c)). 7).
- a cover glass is placed thereon (see FIG. 1 (d)). 8).
- the laminate prepared as described above from above, cover glass / glycerin / sample film / glycerin / slide glass) is set on a haze meter and haze 2 is measured. 9.
- the glass and glycerin used in the above measurement are as follows.
- Front contrast ratio of liquid crystal display device The front contrast of each liquid crystal display device was measured.
- the front contrast was measured by a front contrast measuring device (EZ-contrast) manufactured by ELDIM, and the light quantity during white display and black display was measured.
- Tables 1 and 2 above The above various evaluation results are summarized in Tables 1 and 2 above.
- the examples according to the present invention are superior to the comparative examples in internal haze value, surface roughness Ra, PVA adhesiveness, and front contrast ratio. I understand that.
- the above-mentioned means of the present invention provides a polarizing plate that is excellent in adhesiveness with a polarizer, is safe in work, and can be manufactured with a low environmental burden. You can see that you can. It can also be seen that a liquid crystal display device using the polarizing plate and having a high viewing angle and high visibility can be provided.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Nonlinear Science (AREA)
- Mathematical Physics (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Polarising Elements (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
- Treatments Of Macromolecular Shaped Articles (AREA)
Abstract
Description
式(SI):0.25≦γsh/γsp<1.5
式(SII):1.5≦γsh/γsp≦4.0
ただし、γshは表面エネルギーの水素結合成分、γspは双極子成分を表す。
式(RI):Ro(590)=(nx-ny)×d(nm)
式(RII):Rt(590)={(nx+ny)/2-nz}×d(nm)
〔上式中、Ro(590)は波長590nmにおけるフィルム内の面内リターデーション値を表し、Rt(590)は590nmにおけるフィルム内の厚さ方向のリターデーション値を表す。また、dは光学フィルムの厚さ(nm)を表し、nxは590nmにおけるフィルムの面内の最大の屈折率を表し、遅相軸方向の屈折率ともいう。nyは590nmにおけるフィルム面内で遅相軸に直角な方向の屈折率を表し、nzは590nmにおける厚さ方向におけるフィルムの屈折率を表す。〕
4.前記親水化処理された保護フィルムの内部ヘイズが、0.1以下であることを特徴とする前記第1項から第3項までのいずれか一項に記載の偏光板。
式(SI):0.25≦γsh/γsp<1.5
式(SII):1.5≦γsh/γsp≦4.0
ただし、γshは表面エネルギーの水素結合成分、γspは双極子成分を表す。
本発明の偏光板を構成する保護フィルムの少なくとも一つは、プラズマ処理又はコロナ処理のいずれかで親水化処理された保護フィルムであり、当該保護フィルムの親水化処理前の表面エネルギーが下記式(SI)を満たし、かつ当該保護フィルムの親水化処理後の表面エネルギーが下記式(SII)を満たすことを特徴とする。
式(SI):0.25≦γsh/γsp<1.5
式(SII):1.5≦γsh/γsp≦4.0
ただし、γshは表面エネルギーの水素結合成分、γspは双極子成分を表す。
本発明においては、フィルムの表面自由エネルギーを、次のように測定した。
Young-Dupreの式:WSL=γL(1+cosθ)
WSL:液体/固体間の付着エネルギー
γL:液体の表面自由エネルギー
θ:液体/固体の接触角
拡張Fowkesの式:
WSL=2{(γsdγLd)1/2+(γspγLp)1/2+(γshγLh)1/2}
γL=γLd+γLp+γLh:液体の表面自由エネルギー
γs=γsd+γsp+γsh:固体の表面自由エネルギー
γd、γp、γh:表面自由エネルギーの分散、双極子、水素結合の各成分
標準液体の表面自由エネルギー各成分値(mN/m)は、表5のように既知であるので、接触角の値から3元連立方程式を解くことにより、固体表面の表面エネルギー各成分値(γsd、γsp、γsh)を求めることができる。
本発明に係る親水化処理後の保護フィルムは、内部ヘイズが0.1以下であることが好ましく、より好ましくは0.05以下、更に好ましくは0.03以下である。
ヘイズメーター(濁度計)(型式:NDH 2000、日本電色(株)製)
光源は、5V9Wハロゲン球、受光部は、シリコンフォトセル(比視感度フィルター付き)を用いている。
1.きれいにしたスライドガラスの上にグリセリンを一滴(0.05ml)たらす。このとき液滴に気泡が入らないように注意する。ガラスは見た目がきれいでも汚れていることがあるので必ず洗剤で洗浄したものを使用する(図1(a)参照)。
2.その上にカバーガラスを乗せる。カバーガラスは押さえなくてもグリセリンは広がる。
3.ヘイズメーターにセットしブランクヘイズ1を測定する。
4.スライドガラス上にグリセリン(0.05ml)を滴下する(図1(a)参照)。
5.その上に測定する試料フィルムを気泡が入らないように乗せる(図1(b)参照)。6.試料フィルム上にグリセリン(0.05ml)を滴下する(図1(c)参照)。
7.その上にカバーガラスを載せる(図1(d)参照)。
8.上記のように作製した積層体(上から、カバーガラス/グリセリン/試料フィルム/グリセリン/スライドガラス)をヘイズメーターにセットしヘイズ2を測定する。
9.(ヘイズ2)-(ヘイズ1)=(本発明に係るセルロースエステルフィルムの内部ヘイズ)を算出する。
グリセリン:関東化学製 鹿特級(純度>99.0%) 屈折率1.47
<セルロースエステル>
本発明に係る保護フィルムは、その素材として種々の公知の樹脂を用いることができるが、セルロースエステルを含有するフィルムであることが好ましい。また、当該保護フィルムが、アセチル置換度が2.1以上2.5未満であるジアセチルセルロースを含有するフィルムであることがフィルムの親水化処理前の表面エネルギーが前記式(SI)を満たし、かつ親水化処理後の表面エネルギーが前記式(SII)を満たすように調整し易いという点で好ましい。
カルシウム及びマグネシウムは、セルロースエステルフィルムの原料となるセルロースエステルに含まれるが、セルロースエステル製造過程に添加される酸触媒(特に硫酸)を中和・安定化するため、金属酸化物、金属水酸化物、金属塩(無機酸塩、有機酸塩)として添加されてもよい。またセルロースエステルフィルム製膜時に金属酸化物、金属水酸化物、金属塩(無機酸塩、有機酸塩)として添加してもよい。本発明で言うセルロースエステルフィルムに含まれるカルシウム及びマグネシウムの総量(ppm)は、それらの合計量を指す。
本発明に用いられるセルロースエステルには、フィルムの親水化処理前の表面エネルギーが前記式(SI)を満たし、かつ親水化処理後の表面エネルギーが前記式(SII)を満たす限りにおいて用途に応じた種々の添加剤(加水分解防止剤、位相差調整剤、可塑剤、紫外線吸収剤、酸化防止剤、酸捕捉剤、微粒子等)を加えることができる。
加水分解防止剤としては、例えば、ピラノース構造又はフラノース構造の少なくとも1種を1個以上12個以下有しその構造のOH基の一部がエステル化されたエステル化合物の混合物を好ましく用いることができる。
位相差調整剤は、例えば、下記一般式(1)で表されるエステル系化合物を好ましく用いることができる。
(式中、Bはヒドロキシ基又はカルボン酸残基、Gは炭素数2~12のアルキレングリコール残基又は炭素数6~12のアリールグリコール残基又は炭素数が4~12のオキシアルキレングリコール残基、Aは炭素数4~12のアルキレンジカルボン酸残基又は炭素数6~12のアリールジカルボン酸残基を表し、またnは1以上の整数を表す。)
一般式(1)中、Bで示されるヒドロキシ基又はカルボン酸残基と、Gで示されるアルキレングリコール残基又はオキシアルキレングリコール残基又はアリールグリコール残基、Aで示されるアルキレンジカルボン酸残基又はアリールジカルボン酸残基とから構成されるものであり、通常のエステル系化合物と同様の反応により得られる。
本発明に用いられるセルロースエステルフィルムは、必要に応じて可塑剤を含有することができる。
但し、R1はn価の有機基、nは2以上の正の整数、OH基はアルコール性、および/又はフェノール性水酸基を表す。
(但し、R2は(m+n)価の有機基、mは2以上の正の整数、nは0以上の整数、COOH基はカルボキシル基、OH基はアルコール性又はフェノール性水酸基を表す)
多価カルボン酸エステル化合物の分子量は特に制限はないが、分子量300~1000の範囲であることが好ましく、350~750の範囲であることが更に好ましい。保留性向上の点では大きい方が好ましく、透湿性、セルロースエステルとの相溶性の点では小さい方が好ましい。
紫外線吸収剤は400nm以下の紫外線を吸収することで、耐久性を向上させることを目的としており、特に波長370nmでの透過率が10%以下であることが好ましく、より好ましくは5%以下、更に好ましくは2%以下である。
酸化防止剤は、劣化防止剤ともいわれる。高湿高温の状態に液晶画像表示装置などがおかれた場合には、セルロースエステルフィルムの劣化が起こる場合がある。
セルロースエステルは高温下では酸によっても分解が促進されるため、本発明の光学フィルムに用いる場合においては酸捕捉剤を含有することが好ましい。
滑り性を付与するため、微粒子を添加することが好ましい。
次に、本発明に用いられるセルロースエステルフィルムの製造方法について説明する。
尚、Mはウェブ又はフィルムを製造中又は製造後の任意の時点で採取した試料の質量で、NはMを115℃で1時間の加熱後の質量である。
本発明に用いられるセルロースエステルフィルムの透湿度は、40℃、90%RHで300~1800g/m2・24hが好ましく、更に400~1500g/m2・24hが好ましく、40~1300g/m2・24hが特に好ましい。透湿度はJIS Z 0208に記載の方法に従い測定することができる。
本発明に用いられるセルロースエステルフィルムの面内リターデーション値(Ro)および厚さ方向のリターデーション値(Rt)は、偏光子保護フィルムとして用いる場合には0≦Ro、Rt≦70nmであることが好ましい。より好ましくは0≦Ro≦30nmかつ0≦Rt≦50nmであり、より好ましくは0≦Ro≦10nmかつ0≦Rt≦30nmである。
Rt=((nx+ny)/2-nz)×d
ここにおいて、dはフィルムの厚さ(nm)、屈折率nx(フィルムの面内の最大の屈折率、遅相軸方向の屈折率ともいう)、ny(フィルム面内で遅相軸に直角な方向の屈折率)、nz(厚さ方向におけるフィルムの屈折率)である。
本発明の偏光板は、偏光子の両面が、保護フィルムで挟持されてなる偏光板において、少なくとも片側の保護フィルムが、プラズマ処理又はコロナ処理のいずれかで親水化処理された保護フィルムであることを特徴とする。
以下、本発明に係る偏光板保護フィルムの表面親水化処理に適用できるプラズマ処理、特に大気圧プラズマ処理について説明する。
V1≧IV>V2 又は V1>IV≧V2を満たす。さらに好ましくは、
V1>IV>V2を満たすことである。
各電極部の高周波プローブ(P6015A)を設置し、該高周波プローブをオシロスコープ(Tektronix社製、TDS3012B)に接続し、電圧を測定する。
電極間に放電ガスを供給し、該電極間の電圧を増大させていき、放電が始まる電圧を放電開始電圧IVと定義する。測定器は上記高周波電圧測定と同じである。
高周波電源記号 メーカー 周波数
A1 神鋼電機 3kHz
A2 神鋼電機 5kHz
A3 春日電機 15kHz
A4 神鋼電機 50kHz
A5 ハイデン研究所 100kHz*
A6 パール工業 200kHz
なお、*印はハイデン研究所インパルス高周波電源(連続モードで100kHz)である。
高周波電源記号 メーカー 周波数
B1 パール工業 800kHz
B2 パール工業 2MHz
B3 パール工業 13.56MHz
B4 パール工業 27MHz
B5 パール工業 150MHz
等の市販のものを挙げることができ、何れも好ましく使用できる。
表面親水化処理のうち、コロナ処理(「コロナ放電処理」ともいう。)は、最もよく知られている方法であり、従来公知のいずれの方法、例えば特公昭48-5043号公報、同47-51905号公報、特開昭47-28067号公報、同49-83767号公報、同51-41770号公報、同51-131576号公報等に開示された方法により達成することができる。コロナ処理に使用するコロナ処理機としては、現在プラスチックフィルム等の表面改質の手段として使用されている市販の各種コロナ処理機の適用が可能であり、中でもSOFTAL(ソフタル)社のマルチナイフ電極を有するコロナ処理機は多数本の電極で構成され、さらに電極の間に空気を送る構造となっており、フィルムの加熱防止やフィルム表面に出てくる低分子の除去等が行えるので、エネルギー効率が非常に高く、高コロナ処理が可能となるので、本発明には特に有用なコロナ処理機である。
本発明の親水化処理された偏光板保護フィルムを用いた偏光板は、液晶表示装置に使用することができる。
本発明の偏光板を液晶表示装置に用いることによって、種々の視認性に優れた液晶表示装置を作製することができる。
〈微粒子分散液〉
微粒子(アエロジル R812 日本アエロジル(株)製)11質量部
エタノール 89質量部
以上をディゾルバーで50分間攪拌混合した後、マントンゴーリンで分散を行った。
メチレンクロライドを入れた溶解タンクに、CE-1(ダイセル社ジアセチルセルロース:L20)を添加し、加熱して完全に溶解させた後、これを安積濾紙(株)製の安積濾紙No.244を使用して濾過した。濾過後のセルロースエステル溶液を充分に攪拌しながら、ここに微粒子分散液をゆっくりと添加した。更に、二次粒子の粒径が所定の大きさとなるようにアトライターにて分散を行った。これを日本精線(株)製のファインメットNFで濾過し、微粒子添加液を調製した。
L20 4質量部
微粒子分散液 11質量部
L20を用い、下記組成の主ドープ液を調製した。
メチレンクロライド 300質量部
エタノール 30質量部
L20 100質量部
添加剤A(化合物A-5) 7質量部
添加剤B(化合物B-1) 6質量部
<セルロースエステルフィルム102~104の作製>
添加剤を表1のようになるように変更した以外は同様にしてセルロースエステルフィルム102~104を作製した。
使用したセルロースエステルをCE-2(イーストマンケミカル社のCa394-60S)に、添加剤A、Bを表1のようになるように変更した以外は同様にしてセルロースエステルフィルム105を作製した。
使用したセルロースエステルをCE-3(イーストマンケミカル社のCa398-30)に、添加剤A、Bを表1のようになるように変更した以外は同様にしてセルロースエステルフィルム106を作製した。
使用したセルロースエステルをCE-4(イーストマンケミカル社のCa394-60SとCa398-6の50対50混合物)に、添加剤A、Bを表1のようになるように変更した以外は同様にしてセルロースエステルフィルム107を作製した。
使用したセルロースエステルをCE-5(ダイセル社のLM80)に、添加剤A、Bを表1のようになるように変更した以外は同様にしてセルロースエステルフィルム108を作製した。
使用したセルロースエステルをCE-6(ダイセル社のLT35)に、添加剤A、Bを表1のようになるように変更した以外は同様にしてセルロースエステルフィルム109を作製した。
使用したセルロースエステルをCE-7(イーストマンケミカル社のCAP141-20)に、添加剤A、Bを表1のようになるように変更した以外は同様にしてセルロースエステルフィルム110を作製した。
使用したセルロースエステルをCE-8(アセチル置換度1.56、プロピオニル置換度0.90、総置換度2.46であるセルロースアセテートプロピオネート)に、添加剤A、Bを表1のようになるように変更した以外は同様にしてセルロースエステルフィルム111を作製した。
BDP:ビフェニルジフェニルフォスフェート
PETB:ペンタエリスリトールテトラベンゾエート
EPEG:エチルフタリルエチルグリコレート
<偏光板の作製>
得られたセルロースエステルフィルム101~111を表2~表4に記載した条件で図1に記載の装置を用いて親水化処理を行い、下記に従い偏光板を作製した。
正面コントラスト測定を行う液晶パネルを以下のようにして作製し、液晶表示装置としての特性を評価した。
得られたセルロースエステルフィルムを用い、以下の評価を行った。
フィルムの表面自由エネルギーを、次のように測定した。
Young-Dupreの式:WSL=γL(1+cosθ)
WSL:液体/固体間の付着エネルギー
γL:液体の表面自由エネルギー
θ:液体/固体の接触角
拡張Fowkesの式:
WSL=2{(γsdγLd)1/2+(γspγLp)1/2+(γshγLh)1/2}
γL=γLd+γLp+γLh:液体の表面自由エネルギー
γs=γsd+γsp+γsh:固体の表面自由エネルギー
γd、γp、γh:表面自由エネルギーの分散、双極子、水素結合の各成分
標準液体の表面自由エネルギー各成分値(mN/m)は、表5のように既知であるので、接触角の値から3元連立方程式を解くことにより、固体表面の表面エネルギー各成分値(γsd、γsp、γsh)を求めることができる。
リターデーション値Ro及びRtは、以下の式によって求めた。
Rt=((nx+ny)/2-nz)×d
ここにおいて、dはフィルムの厚さ(nm)、屈折率nx(遅相軸方向の屈折率)、ny(フィルム面内で遅相軸に直角な方向の屈折率)、nz(厚さ方向におけるフィルムの屈折率)である。
作製したセルロースエステルフィルムを、23℃55%RHの環境にて5時間以上調湿した後、下記方法により内部ヘイズ値を評価した(図1参照)。
1.きれいにしたスライドガラスの上にグリセリンを一滴(0.05ml)たらす。このとき液滴に気泡が入らないように注意する。ガラスは見た目がきれいでも汚れていることがあるので必ず洗剤で洗浄したものを使用する(図1参照)。
2.その上にカバーガラスを乗せる。カバーガラスは押さえなくてもグリセリンは広がる。
3.ヘイズメーターにセットしブランクヘイズ1を測定する。
4.スライドガラス上にグリセリン(0.05ml)を滴下する(図1(a)参照)
5.その上に測定する試料フィルムを気泡が入らないように乗せる(図1(b)参照)
6.試料フィルム上にグリセリン(0.05ml)を滴下する(図1(c)参照)
7.その上にカバーガラスを載せる(図1(d)参照)。
8.上記のように作製した積層体(上から、カバーガラス/グリセリン/試料フィルム/グリセリン/スライドガラス)をヘイズメーターにセットしヘイズ2を測定する。
9.(ヘイズ2)-(ヘイズ1)=(本発明のセルロースエステルフィルムの内部ヘイズ)を算出する。
グリセリン:関東化学製 鹿特級(純度>99.0%) 屈折率1.47
(表面粗さRa)
フィルムの表面粗さ(Ra)は、Veeco社製 Wycoにより測定した。
作製したセルロースエステルフィルム(幅手:1980mm、長さ:7800mのロール)の親水化処理後の工程を目視観察して、以下の基準で工程汚染の程度を評価した。
○:工程汚染は観察されない。
×:親水化装置表面もしくはケン化液中に白色異物が観察される。
得られた偏光板を、23℃で相対湿度55%の環境下で、接着面を手で引き剥がし、材料破壊及び剥離性の程度を目視観察して、以下の基準で接着性を評価した。
○:材料(基材)破壊が起こる。
△:一部材料(基材)破壊が起こるが、偏光板保護フィルムと偏光子との界面で剥がれる面積が存在する。
×:偏光板保護フィルムと偏光子との界面で剥がれる。
液晶表示装置について、それぞれの正面コントラストを測定した。正面コントラストの測定は、ELDIM社製の正面コントラスト測定装置(EZ-contrast)により行い、白表示時と黒表示時の光量を測定した。測定結果を、正面コントラストの値によって、下記のように優劣を付けてランク付けを行った。
○:正面コントラスト比=3000:1以上
△:正面コントラスト比=2999:1~2000:1
×:正面コントラスト比=1999:1以下
以上の各種評価結果を、前掲の表1及び表2にまとめて示す。
G 放電ガス
G′ 励起放電ガス
P 送液ポンプ
130 大気圧プラズマ処理装置
131 大気圧プラズマ処理容器
132 放電空間
135 ロール電極(第1電極)
136 角筒型電極群(第2電極)
140 電界印加手段
141 第1電源
142 第2電源
143 第1フィルター
144 第2フィルター
150 ガス供給手段
151 ガス発生装置
152 給気口
153 排気口
160 電極温度調節手段
161 配管
164、167 ガイドロール
165、166 ニップロール
168、169 仕切板
Claims (9)
- 偏光子の両面が、保護フィルムで挟持されてなる偏光板において、少なくとも片側の保護フィルムが、プラズマ処理又はコロナ処理のいずれかで親水化処理された保護フィルムであり、当該保護フィルムの親水化処理前の表面エネルギーが下記式(SI)を満たし、かつ当該保護フィルムの親水化処理後の表面エネルギーが下記式(SII)を満たすことを特徴とする偏光板。
式(SI):0.25≦γsh/γsp<1.5
式(SII):1.5≦γsh/γsp≦4.0
ただし、γshは表面エネルギーの水素結合成分、γspは双極子成分を表す。 - 前記親水化処理された保護フィルムの表面の中心線平均粗さ(Ra)の値が、2.0~10.0nmの範囲内であることを特徴とする請求項1に記載の偏光板。
- 前記保護フィルムが、位相差フィルムであり、下記式(RI)により定義される面内リターデーション値Ro(590)が30~90nmの範囲内であり、下記式(RII)により定義される厚さ方向のリターデーション値Rt(590)が70~300nmの範囲内であることを特徴とする請求項1又は請求項2に記載の偏光板。
式(RI):Ro(590)=(nx-ny)×d(nm)
式(RII):Rt(590)={(nx+ny)/2-nz}×d(nm)
〔上式中、Ro(590)は波長590nmにおけるフィルム内の面内リターデーション値を表し、Rt(590)は590nmにおけるフィルム内の厚さ方向のリターデーション値を表す。また、dは光学フィルムの厚さ(nm)を表し、nxは590nmにおけるフィルムの面内の最大の屈折率を表し、遅相軸方向の屈折率ともいう。nyは590nmにおけるフィルム面内で遅相軸に直角な方向の屈折率を表し、nzは590nmにおける厚さ方向におけるフィルムの屈折率を表す。〕 - 前記親水化処理された保護フィルムの内部ヘイズが、0.1以下であることを特徴とする請求項1から請求項3までのいずれか一項に記載の偏光板。
- 前記親水化処理された保護フィルムが、セルロースエステルを含有するフィルムであることを特徴とする請求項1から請求項4までのいずれか一項に記載の偏光板。
- 前記親水化処理された保護フィルムが、溶解度パラメータ(SP値)が12.0以上13.0以下であるセルロースエステルを含有することを特徴とする請求項1から請求項5までのいずれか一項に記載の偏光板。
- 前記親水化処理された保護フィルムが、アセチル置換度が2.1以上2.5未満であるジアセチルセルロースを含有するフィルムであることを特徴とする請求項1から請求項6までのいずれか一項に記載の偏光板。
- 偏光子の両面が、保護フィルムで挟持されてなる偏光板の製造方法であって、少なくとも片側の保護フィルムに、プラズマ処理又はコロナ処理のいずれかで親水化処理を施す工程を有し、かつ、当該保護フィルムの親水化処理前の表面エネルギーが下記式(SI)を満たし、かつ当該保護フィルムの親水化処理後の表面エネルギーが下記式(SII)を満たすことを特徴とする偏光板の製造方法。
式(SI):0.25≦γsh/γsp<1.5
式(SII):1.5≦γsh/γsp≦4.0
ただし、γshは表面エネルギーの水素結合成分、γspは双極子成分を表す。 - 液晶セル及びその両側に配置された二枚の偏光板からなり、当該偏光板の少なくとも一枚が請求項1から請求項7までのいずれか一項に記載の偏光板又は請求項8に記載の偏光板の製造方法で製造された偏光板であることを特徴とする液晶表示装置。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/383,330 US9057842B2 (en) | 2009-07-15 | 2010-01-21 | Polarizing plate, method of manufacturing the same and liquid crystal display employing the same |
CN2010800313627A CN102472857B (zh) | 2009-07-15 | 2010-01-21 | 偏振片、其制造方法以及使用该偏振片的液晶显示装置 |
KR1020127000790A KR101679450B1 (ko) | 2009-07-15 | 2010-01-21 | 편광판, 그의 제조 방법, 및 그를 이용한 액정 표시 장치 |
JP2011522745A JP5218659B2 (ja) | 2009-07-15 | 2010-01-21 | 偏光板、その製造方法、及びそれを用いた液晶表示装置 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2009-166458 | 2009-07-15 | ||
JP2009166458 | 2009-07-15 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2011007587A1 true WO2011007587A1 (ja) | 2011-01-20 |
Family
ID=43449197
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2010/050694 WO2011007587A1 (ja) | 2009-07-15 | 2010-01-21 | 偏光板、その製造方法、及びそれを用いた液晶表示装置 |
Country Status (5)
Country | Link |
---|---|
US (1) | US9057842B2 (ja) |
JP (1) | JP5218659B2 (ja) |
KR (1) | KR101679450B1 (ja) |
CN (1) | CN102472857B (ja) |
WO (1) | WO2011007587A1 (ja) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2012181318A (ja) * | 2011-03-01 | 2012-09-20 | Konica Minolta Advanced Layers Inc | λ/4板、λ/4板の製造方法、円偏光板、液晶表示装置、及び立体映像表示装置 |
WO2013161647A1 (ja) * | 2012-04-24 | 2013-10-31 | コニカミノルタ株式会社 | 偏光板の製造方法 |
US20130293812A1 (en) * | 2011-01-11 | 2013-11-07 | Konica Minolta, Inc. | Optical film, polarizing plate equipped with the optical film, process for manufacture of the polarizing plate, and liquid crystal display device |
JPWO2013038829A1 (ja) * | 2011-09-13 | 2015-03-26 | コニカミノルタ株式会社 | 偏光板及び液晶表示装置 |
WO2016143715A1 (ja) * | 2015-03-06 | 2016-09-15 | コニカミノルタ株式会社 | 透明導電体及び透明導電体の製造方法 |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101525295B1 (ko) * | 2010-03-03 | 2015-06-02 | 코니카 미놀타 어드밴스드 레이어즈 인코포레이티드 | 편광판의 제조 방법, 그것을 이용한 편광판, 및 액정 표시 장치 |
KR20170042668A (ko) * | 2014-09-30 | 2017-04-19 | 코니카 미놀타 가부시키가이샤 | 편광판 및 액정 표시 장치 |
JP6798109B2 (ja) * | 2016-01-21 | 2020-12-09 | 横浜ゴム株式会社 | 部材の表面処理方法、及び、積層部材の製造方法 |
TWI702426B (zh) * | 2018-11-20 | 2020-08-21 | 住華科技股份有限公司 | 偏光板及包含其之顯示裝置的製造方法 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002082223A (ja) * | 2000-09-08 | 2002-03-22 | Konica Corp | 偏光板用保護フィルム、光学用フィルムおよび画像表示材料 |
JP2007169523A (ja) * | 2005-12-22 | 2007-07-05 | Fujifilm Corp | セルロース誘導体フィルム、該セルロース誘導体フィルムを用いた光学補償フィルム、偏光板および液晶表示装置 |
JP2009025604A (ja) * | 2007-07-20 | 2009-02-05 | Konica Minolta Opto Inc | 偏光板保護フィルム、その製造方法及び製造装置、並びに偏光板、その製造方法及び表示装置 |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI225499B (en) * | 1999-04-15 | 2004-12-21 | Konishiroku Photo Ind | Protective film for polarizing plate |
JP4688116B2 (ja) | 1999-04-15 | 2011-05-25 | コニカミノルタホールディングス株式会社 | 偏光板用保護フィルム |
JP2002082226A (ja) | 2000-06-21 | 2002-03-22 | Fuji Photo Film Co Ltd | 光学補償シート、偏光板および液晶表示装置 |
JP2003255131A (ja) * | 2002-03-05 | 2003-09-10 | Konica Corp | 光学フィルム、偏光板保護フィルム、偏光板及び基材表面の処理方法 |
JP2005068314A (ja) * | 2003-08-26 | 2005-03-17 | Fuji Photo Film Co Ltd | 光学用セルロースアシレートフィルムと、その製造方法 |
CN1727916A (zh) * | 2004-07-28 | 2006-02-01 | 力特光电科技股份有限公司 | 增加可视角度的偏光板结构及形成方法 |
TW200632002A (en) * | 2004-11-30 | 2006-09-16 | Fuji Photo Film Co Ltd | Polarizing plate and liquid crystal display device comprising the same |
JP4686247B2 (ja) * | 2005-04-22 | 2011-05-25 | 富士フイルム株式会社 | ポリマーフィルム並びにそれを用いた光学フィルム、偏光板及び画像表示装置 |
JP2007015366A (ja) * | 2005-06-08 | 2007-01-25 | Fujifilm Corp | セルロースアシレートフィルムの製造方法、セルロースアシレートフィルム、光学補償フィルム、偏光板及び液晶表示装置。 |
KR101377911B1 (ko) * | 2006-07-18 | 2014-03-25 | 다이니폰 인사츠 가부시키가이샤 | 위상차 필름, 휘도 향상 필름, 편광판, 위상차 필름의 제조 방법 및 액정 표시 장치 |
US20080049323A1 (en) * | 2006-07-27 | 2008-02-28 | Fujifilm Corporation | Optical film, production method of optical film, polarizing plate and liquid crystal display device |
-
2010
- 2010-01-21 CN CN2010800313627A patent/CN102472857B/zh active Active
- 2010-01-21 WO PCT/JP2010/050694 patent/WO2011007587A1/ja active Application Filing
- 2010-01-21 KR KR1020127000790A patent/KR101679450B1/ko active IP Right Grant
- 2010-01-21 JP JP2011522745A patent/JP5218659B2/ja active Active
- 2010-01-21 US US13/383,330 patent/US9057842B2/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002082223A (ja) * | 2000-09-08 | 2002-03-22 | Konica Corp | 偏光板用保護フィルム、光学用フィルムおよび画像表示材料 |
JP2007169523A (ja) * | 2005-12-22 | 2007-07-05 | Fujifilm Corp | セルロース誘導体フィルム、該セルロース誘導体フィルムを用いた光学補償フィルム、偏光板および液晶表示装置 |
JP2009025604A (ja) * | 2007-07-20 | 2009-02-05 | Konica Minolta Opto Inc | 偏光板保護フィルム、その製造方法及び製造装置、並びに偏光板、その製造方法及び表示装置 |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20130293812A1 (en) * | 2011-01-11 | 2013-11-07 | Konica Minolta, Inc. | Optical film, polarizing plate equipped with the optical film, process for manufacture of the polarizing plate, and liquid crystal display device |
US9223070B2 (en) * | 2011-01-11 | 2015-12-29 | Konica Minolta, Inc. | Optical film, polarizing plate equipped with the optical film, process for manufacture of the polarizing plate, and liquid crystal display device |
JP2012181318A (ja) * | 2011-03-01 | 2012-09-20 | Konica Minolta Advanced Layers Inc | λ/4板、λ/4板の製造方法、円偏光板、液晶表示装置、及び立体映像表示装置 |
JPWO2013038829A1 (ja) * | 2011-09-13 | 2015-03-26 | コニカミノルタ株式会社 | 偏光板及び液晶表示装置 |
WO2013161647A1 (ja) * | 2012-04-24 | 2013-10-31 | コニカミノルタ株式会社 | 偏光板の製造方法 |
CN104254791A (zh) * | 2012-04-24 | 2014-12-31 | 柯尼卡美能达株式会社 | 偏振片的制造方法 |
JPWO2013161647A1 (ja) * | 2012-04-24 | 2015-12-24 | コニカミノルタ株式会社 | 偏光板の製造方法 |
WO2016143715A1 (ja) * | 2015-03-06 | 2016-09-15 | コニカミノルタ株式会社 | 透明導電体及び透明導電体の製造方法 |
JPWO2016143715A1 (ja) * | 2015-03-06 | 2017-12-21 | コニカミノルタ株式会社 | 透明導電体及び透明導電体の製造方法 |
Also Published As
Publication number | Publication date |
---|---|
KR20120033329A (ko) | 2012-04-06 |
KR101679450B1 (ko) | 2016-11-24 |
US20120133868A1 (en) | 2012-05-31 |
CN102472857A (zh) | 2012-05-23 |
CN102472857B (zh) | 2013-10-30 |
JP5218659B2 (ja) | 2013-06-26 |
JPWO2011007587A1 (ja) | 2012-12-20 |
US9057842B2 (en) | 2015-06-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5218659B2 (ja) | 偏光板、その製造方法、及びそれを用いた液晶表示装置 | |
TWI391428B (zh) | 延遲膜及使用彼之偏光板和顯示裝置 | |
JP5725011B2 (ja) | 偏光板の製造方法、それを用いた偏光板、及び液晶表示装置 | |
WO2011016279A1 (ja) | セルロースアセテートフィルム、偏光板及び液晶表示装置 | |
JP6086117B2 (ja) | 偏光板の製造方法 | |
JP5720687B2 (ja) | 位相差フィルム、及びそれを用いた偏光板、液晶表示装置 | |
JP5821849B2 (ja) | セルロースアセテートフィルムの製造方法 | |
JP5776362B2 (ja) | セルロースエステルフィルムおよびその製造方法、並びにこれを用いた位相差フィルムおよび表示装置 | |
WO2011001700A1 (ja) | セルロースエステルフィルム及びそれを用いた偏光板、液晶表示装置 | |
TWI637850B (zh) | 偏光板及液晶顯示裝置 | |
JP2011123401A (ja) | 偏光板とそれを用いた液晶表示装置 | |
TWI519830B (zh) | A polarizing plate, a method for manufacturing the same, and a liquid crystal display device using the same | |
JP5040608B2 (ja) | 光学用フィルムの製造方法、光学用フィルム、偏光板及び液晶表示装置 | |
JP5962002B2 (ja) | 偏光板およびこれを用いた表示装置 | |
WO2012063559A1 (ja) | 斜め延伸用原反フィルム | |
JP2005314613A (ja) | セルロースアシレートフィルム、該フイルムを用いた光学フィルム及び画像表示装置 | |
JP2013142786A (ja) | 位相差フィルム、偏光板及び液晶表示装置 | |
JP2005290347A (ja) | セルロースアシレートフィルム、該フイルムを用いた光学フィルム、及び画像表示装置 | |
JP2008307730A (ja) | 光学用フィルムの製造方法、光学用フィルム、偏光板及び液晶表示装置 | |
TW201226452A (en) | Cellulose ester film, and polarizing plate and liquid crystal display device using the same | |
JP2010026200A (ja) | 液晶表示装置 | |
JP2013126727A (ja) | 光学フィルムの製造方法 | |
JP2012108349A (ja) | 位相差フィルム、その製造方法、偏光板、及び液晶表示装置 | |
JP2012118177A (ja) | セルロースアシレートフィルム、セルロースアシレートフィルムの製造方法、及び液晶表示装置 | |
JP2005173307A (ja) | 光学補償フィルム及びその製造方法、並びにそれを用いた偏光板及び液晶表示装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 201080031362.7 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 10799651 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2011522745 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 13383330 Country of ref document: US |
|
ENP | Entry into the national phase |
Ref document number: 20127000790 Country of ref document: KR Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 10799651 Country of ref document: EP Kind code of ref document: A1 |