WO2015020044A1 - Original film for manufacturing optical film - Google Patents
Original film for manufacturing optical film Download PDFInfo
- Publication number
- WO2015020044A1 WO2015020044A1 PCT/JP2014/070603 JP2014070603W WO2015020044A1 WO 2015020044 A1 WO2015020044 A1 WO 2015020044A1 JP 2014070603 W JP2014070603 W JP 2014070603W WO 2015020044 A1 WO2015020044 A1 WO 2015020044A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- film
- optical film
- producing
- optical
- hydroxymethyl group
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
- C08F8/12—Hydrolysis
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F216/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal or ketal radical
- C08F216/02—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal or ketal radical by an alcohol radical
- C08F216/04—Acyclic compounds
- C08F216/06—Polyvinyl alcohol ; Vinyl alcohol
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F218/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an acyloxy radical of a saturated carboxylic acid, of carbonic acid or of a haloformic acid
- C08F218/02—Esters of monocarboxylic acids
- C08F218/04—Vinyl esters
- C08F218/08—Vinyl acetate
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2329/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Derivatives of such polymer
- C08J2329/02—Homopolymers or copolymers of unsaturated alcohols
- C08J2329/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
-
- 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
Definitions
- the present invention relates to a raw film for producing an optical film such as a polarizing film, which contains a hydroxymethyl group-containing vinyl alcohol polymer having a 1,3-diol structure, and a method for producing an optical film using the same. .
- a polarizing plate having a light transmission and shielding function is a basic component of a liquid crystal display (LCD) together with a liquid crystal that changes a polarization state of light.
- LCD liquid crystal display
- Many polarizing plates have a structure in which a protective film such as a cellulose triacetate (TAC) film is bonded to the surface of a polarizing film.
- TAC cellulose triacetate
- VVA polyvinyl alcohol polymer
- matrix iodine dye I 3 - and I 5 -, etc.
- dichroic dye such as dichroic organic dyes What is adsorbed is the mainstream.
- LCDs have come to be used in a wide range of small devices such as calculators and watches, mobile phones, notebook computers, liquid crystal monitors, liquid crystal color projectors, liquid crystal televisions, in-vehicle navigation systems, and measurement devices used indoors and outdoors.
- polarizing films that have high polarization and transparency, excellent optical properties, and excellent hue.
- a polyvinyl alcohol film for a polarizing film made of a specific PVA containing 0.01 to 1 mol% of a hydrophilic functional group such as a carboxylic acid group or an ⁇ -hydroxy- ⁇ -olefin group is stretched and oriented. It is known that the processability and the adsorption processability of the dichroic substance are excellent (see Patent Document 1). In addition, it is known that a specific optical PVA film containing a specific PVA containing a 1,2-glycol bond in the side chain is excellent in optical properties and stretchability (see Patent Document 2).
- the present invention is excellent in stretchability, can produce an optical film with good productivity, and can easily produce an optical film excellent in both optical properties and hue. It aims at providing the manufacturing method of a film and an optical film using the film.
- the above-described problem is caused by a film containing a hydroxymethyl group-containing PVA containing a specific structural unit having a 1,3-diol structure in the main chain.
- the present invention has been completed by finding that it can be solved and by further studying based on the findings.
- a raw film for producing an optical film comprising a vinyl alcohol unit and a hydroxymethyl group-containing PVA containing a structural unit represented by the following formula (1);
- an optical film can be produced with good stretchability, an optical film can be produced with good productivity, and an optical film excellent in both optical properties and hue can be easily produced.
- An anti-film and a method for producing an optical film using the same are provided.
- the raw film for producing an optical film of the present invention contains a vinyl alcohol unit and a hydroxymethyl group-containing PVA containing a structural unit represented by the following formula (1).
- the raw film for producing an optical film of the present invention has improved stretchability because the hydroxymethyl group-containing PVA contained therein contains a structural unit having a 1,3-diol structure represented by the above formula (1). Yes.
- an optical film excellent in both optical characteristics and hue can be easily produced.
- the present invention is not limited in any way, the reason why the above-described advantages can be obtained is that the crystallinity is lowered by the structural unit represented by the formula (1) and the high based on the 1,3-diol structure. The influence of hydrogen bonding force is considered.
- the content of the structural unit represented by the formula (1) in the hydroxymethyl group-containing PVA is not particularly limited, but is 0.1 to 2 when the number of moles of all structural units constituting the hydroxymethyl group-containing PVA is 100 mol%. It is preferably in the range of mol%, more preferably in the range of 0.2 to 1.9 mol%, still more preferably in the range of 0.3 to 1.8 mol%.
- the said content rate is 0.1 mol% or more, the drawability of a film improves more and the optical film which is excellent in a hue is obtained.
- the content is 2 mol% or less, dissolution of the film during the production of the optical film can be more effectively prevented, and an optical film excellent in optical properties can be obtained.
- the structural unit refers to a repeating unit constituting a polymer.
- the degree of polymerization of the hydroxymethyl group-containing PVA is preferably in the range of 1,500 to 6,000, more preferably in the range of 1,800 to 5,000, and 2,000 to 4,000. More preferably, it is in the range.
- the degree of polymerization is 1,500 or more, the durability of an optical film such as a polarizing film obtained by uniaxially stretching the film can be further improved.
- the degree of polymerization is 6,000 or less, it is possible to suppress an increase in manufacturing cost, poor process passability during film formation, and the like.
- the polymerization degree of the hydroxymethyl group-containing PVA in the present specification means an average polymerization degree measured according to the description of JIS K6726-1994.
- the saponification degree of the hydroxymethyl group-containing PVA is preferably 95 mol% or more, more preferably 96 mol% or more from the viewpoint of water resistance of an optical film such as a polarizing film obtained by uniaxially stretching the film. Preferably, it is 98 mol% or more.
- the degree of saponification of hydroxymethyl group-containing PVA is a structural unit (typical) of hydroxymethyl group-containing PVA that can be converted into vinyl alcohol units (—CH 2 —CH (OH) —) by saponification. Is the ratio (mol%) of the number of moles of the vinyl alcohol unit to the total number of moles of the vinyl ester unit) and the vinyl alcohol unit.
- the degree of saponification can be measured according to the description of JIS K6726-1994, taking into consideration the amount of the structural unit represented by formula (1) and its derivatives.
- the method for producing the hydroxymethyl group-containing PVA is not particularly limited.
- a vinyl ester copolymer obtained by copolymerizing a vinyl ester monomer and an unsaturated monomer copolymerizable therewith and convertible to the structural unit represented by the formula (1) are converted to vinyl alcohol units, while structural units derived from unsaturated monomers that can be converted to structural units represented by formula (1) are converted to structural units represented by formula (1).
- a method is mentioned.
- a specific example of the unsaturated monomer that can be converted into the structural unit represented by the formula (1) is shown in the following formula (2).
- R represents an alkyl group having 1 to 10 carbon atoms.
- the structure of R is not particularly limited, and may partially have a branched or cyclic structure. Moreover, a part may be substituted with other functional groups.
- R is preferably an alkyl group having 1 to 5 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, Examples thereof include a linear or branched alkyl group such as a pentyl group. Examples of the substituent that R may have include an alkoxy group, a halogen atom, and a hydroxyl group. A plurality of R may be the same or different from each other.
- Examples of the unsaturated monomer represented by the formula (2) include 1,3-diacetoxy-2-methylenepropane, 1,3-dipropionyloxy-2-methylenepropane, and 1,3-dibutyryloxy-2. -Methylenepropane and the like. Of these, 1,3-diacetoxy-2-methylenepropane is preferably used from the viewpoint of ease of production.
- the unsaturated monomer represented by the formula (2) is a vinyl ester monomer compared with other allylic unsaturated monomers (for example, allyl glycidyl ether) generally used for modification of PVA.
- the copolymerization reaction proceeds easily. Therefore, there are few restrictions on the amount of modification and the degree of polymerization during polymerization, and a hydroxymethyl group-containing PVA having a high degree of modification and a high degree of polymerization can be easily obtained.
- the hydroxymethyl group-containing PVA in the present invention is excellent in terms of environment and cost during industrial production. Yes.
- the vinyl ester monomer used for the production of the hydroxymethyl group-containing PVA is not particularly limited.
- vinyl acidate, vinyl caprylate, vinyl caprate, vinyl laurate, vinyl palmitate, vinyl stearate, vinyl oleate, and vinyl benzoate from the economical viewpoint, vinyl acetate is preferred.
- the polymerization method for copolymerizing the unsaturated monomer represented by formula (2) and the vinyl ester monomer may be any method such as batch polymerization, semi-batch polymerization, continuous polymerization, and semi-continuous polymerization.
- the polymerization method known methods such as a bulk polymerization method, a solution polymerization method, a suspension polymerization method, and an emulsion polymerization method can be applied.
- a bulk polymerization method or a solution polymerization method in which polymerization is allowed to proceed in a solvent-free or solvent such as alcohol is usually employed.
- an emulsion polymerization method is also preferred.
- the solvent of the solution polymerization method is not particularly limited, for example, alcohol.
- the alcohol used as the solvent for the solution polymerization method is, for example, a lower alcohol such as methanol, ethanol, or propanol.
- the amount of solvent used in the polymerization system may be selected in consideration of the chain transfer of the solvent in accordance with the degree of polymerization of the target hydroxymethyl group-containing PVA. For example, when the solvent is methanol, it is included in the solvent and the polymerization system.
- the polymerization initiator used for copolymerization of the unsaturated monomer represented by the formula (2) and the vinyl ester monomer is a known polymerization initiator such as an azo initiator or a peroxide initiator.
- the redox initiator may be selected according to the polymerization method.
- Examples of the azo initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (4-methoxy-2,4- Dimethylvaleronitrile).
- peroxide initiator examples include percarbonate compounds such as diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, and diethoxyethyl peroxydicarbonate; t-butyl peroxyneodecanate, ⁇ - Perester compounds such as cumylperoxyneodecanate; acetylcyclohexylsulfonyl peroxide; 2,4,4-trimethylpentyl-2-peroxyphenoxyacetate; acetyl peroxide. Potassium persulfate, ammonium persulfate, hydrogen peroxide, or the like may be combined with the above initiator to form a polymerization initiator.
- percarbonate compounds such as diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, and diethoxyethyl peroxydicarbonate
- the redox initiator is, for example, a polymerization initiator in which the peroxide initiator is combined with a reducing agent such as sodium hydrogen sulfite, sodium hydrogen carbonate, tartaric acid, L-ascorbic acid, or longalite.
- a reducing agent such as sodium hydrogen sulfite, sodium hydrogen carbonate, tartaric acid, L-ascorbic acid, or longalite.
- the amount of the polymerization initiator used varies depending on the type of the polymerization initiator and cannot be determined unconditionally, but may be selected according to the polymerization rate. For example, when 2,2′-azobisisobutyronitrile or acetyl peroxide is used as the polymerization initiator, 0.01 to 0.2 mol% is preferable with respect to the vinyl ester monomer, and 0.02 to 0 More preferred is 15 mol%.
- the polymerization temperature is not particularly limited, but is suitably about room temperature to 150 ° C., preferably 40 ° C
- the copolymerization of the unsaturated monomer represented by the formula (2) and the vinyl ester monomer may be performed in the presence of a chain transfer agent.
- the chain transfer agent include aldehydes such as acetaldehyde and propionaldehyde; ketones such as acetone and methyl ethyl ketone; mercaptans such as 2-hydroxyethanethiol; and phosphinic acid salts such as sodium phosphinate monohydrate. Of these, aldehydes and ketones are preferably used.
- the amount of chain transfer agent used can be determined according to the chain transfer coefficient of the chain transfer agent to be used and the degree of polymerization of the target hydroxymethyl group-containing PVA. The amount is preferably 0.1 to 10 parts by mass.
- the above hydroxymethyl group-containing PVA can be obtained by saponifying a vinyl ester copolymer obtained by copolymerization of an unsaturated monomer represented by formula (2) and a vinyl ester monomer. .
- the vinyl ester unit in the vinyl ester copolymer is converted to a vinyl alcohol unit.
- the ester bond of the structural unit derived from the unsaturated monomer represented by the formula (2) is also saponified and converted into a structural unit having a 1,3-diol structure represented by the formula (1). Therefore, the hydroxymethyl group-containing PVA can be produced without further reaction such as hydrolysis after saponification.
- the saponification of the vinyl ester copolymer can be performed in a state where the vinyl ester copolymer is dissolved in, for example, alcohol or hydrous alcohol.
- the alcohol used for saponification include lower alcohols such as methanol and ethanol, preferably methanol.
- the alcohol used for saponification may contain other solvents such as acetone, methyl acetate, ethyl acetate, and benzene at a ratio of 40% by mass or less of the mass, for example.
- the catalyst used for saponification is, for example, an alkali metal hydroxide such as potassium hydroxide or sodium hydroxide, an alkali catalyst such as sodium methylate, or an acid catalyst such as mineral acid.
- the temperature at which saponification is performed is not limited, but is preferably within the range of 20 to 60 ° C.
- the product is pulverized, washed and dried to obtain a hydroxymethyl group-containing PVA.
- the saponification method is not limited to the method described above, and a known method can be applied.
- the hydroxymethyl group-containing PVA can further include other structural units other than the structural unit represented by the formula (1), the vinyl alcohol unit, and the vinyl ester unit.
- the other structural unit include a structural unit derived from an ethylenically unsaturated monomer copolymerizable with a vinyl ester monomer.
- the proportion of the total of the structural unit represented by the formula (1), the vinyl alcohol unit and the vinyl ester unit is 100 mol% of the number of moles of all the structural units constituting the hydroxymethyl group-containing PVA. 80 mol% or more, preferably 90 mol% or more, more preferably 95 mol% or more, and may be 99 mol% or more.
- ethylenically unsaturated monomer examples include ⁇ -olefins such as ethylene, propylene, n-butene, isobutylene and 1-hexene; acrylic acid and salts thereof; unsaturated monomer having an acrylate group.
- Body methacrylic acid and salts thereof; unsaturated monomer having methacrylic ester group; acrylamide; N-methylacrylamide, N-ethylacrylamide, N, N-dimethylacrylamide, diacetoneacrylamide, acrylamidepropanesulfonic acid and salts thereof Acrylamide derivatives such as acrylamidepropyldimethylamine and salts thereof (for example, quaternary salts); methacrylamide; N-methyl methacrylamide, N-ethyl methacrylamide, methacrylamide propane sulfonic acid and salts thereof, methacrylamide propylene Methacrylamide derivatives such as dimethylamine and its salts (eg quaternary salts); methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, i-propyl vinyl ether, n-butyl vinyl ether, i-butyl vinyl ether, t-butyl vinyl ether, dodecyl vinyl ether , Vinyl
- an unsaturated dicarboxylic acid and a salt or ester thereof; vinylsilyl compounds such as vinyltrimethoxysilane; and isopropenyl acetate since the stretchability is improved and the film can be stretched at a higher temperature, the occurrence of troubles such as breakage of the stretch during the production of the optical film is reduced, and the productivity of the optical film is further improved. preferable.
- the hydroxymethyl group-containing PVA contains an ethylene unit
- the content of the ethylene unit is 100 in terms of the number of moles of all structural units constituting the hydroxymethyl group-containing PVA from the viewpoints of stretchability and stretchable temperature as described above.
- the mol% is preferably 1 to 4 mol%, particularly preferably 2 to 3 mol%.
- the arrangement order of the structural unit represented by the formula (1) in the hydroxymethyl group-containing PVA, the vinyl alcohol unit, and other arbitrary structural units is not particularly limited, and may be any of random, block, alternating, and the like.
- the raw film for producing an optical film of the present invention can contain a plasticizer in addition to the hydroxymethyl group-containing PVA.
- Preferred plasticizers include polyhydric alcohols, and specific examples include ethylene glycol, glycerin, propylene glycol, diethylene glycol, diglycerin, triethylene glycol, tetraethylene glycol, trimethylolpropane, and the like.
- the raw film for producing an optical film of the present invention can contain one or more of these plasticizers. Among these, glycerin is preferable in terms of the effect of improving stretchability.
- the plasticizer content in the raw film for producing an optical film of the present invention is preferably in the range of 1 to 20 parts by mass with respect to 100 parts by mass of the hydroxymethyl group-containing PVA contained therein. More preferably, it is within the range of 5 parts by weight, and even more preferably within the range of 5 to 15 parts by weight.
- the content is 1 part by mass or more, the stretchability of the film is further improved.
- the content is 20 parts by mass or less, it is possible to prevent the film from becoming too flexible and handling properties from being lowered.
- the raw film for producing an optical film of the present invention further includes a filler, a processing stabilizer such as a copper compound, a weather resistance stabilizer, a colorant, an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, Flame retardants, other thermoplastic resins, lubricants, fragrances, defoamers, deodorants, extenders, release agents, mold release agents, reinforcing agents, cross-linking agents, fungicides, preservatives, crystallization rate retarders Additives such as can be blended as needed.
- a processing stabilizer such as a copper compound, a weather resistance stabilizer, a colorant, an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, Flame retardants, other thermoplastic resins, lubricants, fragrances, defoamers, deodorants, extenders, release agents, mold release agents, reinforcing agents, cross-linking agents, fungicides, preservatives, crystallization rate retarders
- the proportion of the total of the hydroxymethyl group-containing PVA and the plasticizer in the raw film for producing an optical film of the present invention is preferably 80% by mass or more based on the mass of the original film for producing an optical film, 90 More preferably, it is more than 95 mass%, and it is still more preferable that it is 95 mass% or more.
- the degree of swelling of the original film for producing an optical film of the present invention is preferably in the range of 160 to 240%, more preferably in the range of 170 to 230%, and in the range of 180 to 220%. It is particularly preferred.
- the degree of swelling is 160% or more, the crystallization can be prevented from proceeding extremely, and the film can be stably stretched to a higher magnification.
- the degree of swelling is 240% or less, dissolution during stretching is suppressed, and stretching is possible even under higher temperature conditions.
- the degree of swelling of the optical film-producing original film refers to the mass when the optical film-producing original film is immersed in distilled water at 30 ° C. for 30 minutes, and is dried at 105 ° C. for 16 hours after immersion. It means the percentage of the value obtained by dividing by the mass after the measurement, and can be specifically measured by the method described later in the examples.
- the thickness of the raw film for producing an optical film of the present invention is not particularly limited, but is generally 1 to 100 ⁇ m, more preferably 5 to 75 ⁇ m, and particularly preferably about 10 to 60 ⁇ m.
- the thickness is too thin, there is a tendency that stretching breakage is likely to occur during uniaxial stretching treatment for producing an optical film such as a polarizing film.
- the said thickness is too thick, at the time of the uniaxial stretching process for manufacturing an optical film, it will become easy to generate
- the width of the original film for producing an optical film of the present invention is not particularly limited, and can be determined according to the use of the produced optical film. In recent years, since the enlargement of screens of liquid crystal televisions and liquid crystal monitors has progressed, it is preferable for these applications to have a width of the original film for producing optical films of 3 m or more. On the other hand, if the width of the raw film for producing an optical film is too large, it is difficult to uniformly carry out uniaxial stretching itself when producing an optical film with an apparatus that has been put into practical use.
- the width of the anti-film is preferably 7 m or less.
- the production method of the raw film for producing an optical film of the present invention is not particularly limited, and a production method in which the thickness and width of the film after film formation are more uniform can be preferably employed.
- One or two or more of the above-described hydroxymethyl group-containing PVA constituting the anti-film and, if necessary, the above-described plasticizer, additive, and surfactant described later are dissolved in the liquid medium.
- the film-forming stock solution, hydroxymethyl group-containing PVA, and optionally further containing one or more of plasticizers, additives, surfactants, liquid media, etc., and hydroxymethyl group-containing PVA Can be produced using a film-forming stock solution in which is melted. When the film-forming stock solution contains at least one of a plasticizer, an additive, and a surfactant, it is preferable that these components are uniformly mixed.
- liquid medium used for the preparation of the membrane forming stock solution examples include water, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, ethylene glycol, glycerin, propylene glycol, diethylene glycol, triethylene glycol, and tetraethylene glycol. , Trimethylolpropane, ethylenediamine, diethylenetriamine and the like, and one or more of them can be used. Among these, water is preferable from the viewpoint of environmental load and recoverability.
- the volatile fraction of the film-forming stock solution (content ratio in the film-forming stock solution of volatile components such as liquid media removed by volatilization or evaporation during film formation) varies depending on the film-forming method, film-forming conditions, etc. Specifically, it is preferably in the range of 50 to 95% by mass, more preferably in the range of 55 to 90% by mass, and still more preferably in the range of 60 to 85% by mass.
- the film-forming stock solution has a volatile content of 50% by mass or more, so that the viscosity of the film-forming stock solution does not become too high, and filtration and defoaming are smoothly performed during the preparation of the film-forming stock solution, and there are few foreign substances and defects. Is easy to manufacture.
- the volatile fraction of the film-forming stock solution is 95% by mass or less, the concentration of the film-forming stock solution does not become too low, and industrial film production is facilitated.
- the film forming stock solution preferably contains a surfactant.
- a surfactant By including the surfactant, the film-forming property is improved and the occurrence of uneven thickness of the film is suppressed, and the film is easily peeled off from the metal roll or belt used for film formation.
- the film may contain a surfactant.
- the kind of said surfactant is not specifically limited, From a viewpoint of the peelability from a metal roll or a belt, an anionic surfactant or a nonionic surfactant is preferable.
- anionic surfactant for example, a carboxylic acid type such as potassium laurate; a sulfuric acid ester type such as polyoxyethylene lauryl ether sulfate and octyl sulfate; and a sulfonic acid type such as dodecylbenzene sulfonate are suitable.
- a carboxylic acid type such as potassium laurate
- a sulfuric acid ester type such as polyoxyethylene lauryl ether sulfate and octyl sulfate
- a sulfonic acid type such as dodecylbenzene sulfonate
- Nonionic surfactants include, for example, alkyl ether types such as polyoxyethylene oleyl ether; alkylphenyl ether types such as polyoxyethylene octylphenyl ether; alkyl ester types such as polyoxyethylene laurate; polyoxyethylene laurylamino Alkylamine type such as ether; alkylamide type such as polyoxyethylene lauric acid amide; polypropylene glycol ether type such as polyoxyethylene polyoxypropylene ether; alkanolamide type such as lauric acid diethanolamide and oleic acid diethanolamide; polyoxy An allyl phenyl ether type such as alkylene allyl phenyl ether is preferred.
- surfactants can be used alone or in combination of two or more.
- the content thereof is preferably in the range of 0.01 to 0.5 parts by weight with respect to 100 parts by weight of the hydroxymethyl group-containing PVA contained in the film-forming stock solution.
- the content is more preferably in the range of 0.02 to 0.3 parts by mass, and particularly preferably in the range of 0.05 to 0.1 parts by mass.
- the content is 0.01 mass part or more, film forming property and peelability improve more.
- the content is 0.5 parts by mass or less, it is possible to prevent the surfactant from bleeding out on the surface of the optical film-producing raw film and causing blocking to deteriorate handling properties. .
- Examples of the film forming method for forming an optical film manufacturing raw film using the above film forming stock solution include a cast film forming method, an extrusion film forming method, a wet film forming method, and a gel film forming method. Can be mentioned. These film forming methods may be used alone or in combination of two or more. Among these film forming methods, the cast film forming method and the extrusion film forming method are preferable because a raw film for producing an optical film having a uniform thickness and width and good physical properties can be obtained. The formed film can be dried or heat-treated as necessary.
- a method for producing a raw film for producing an optical film of the present invention for example, using the T-type slit die, hopper plate, I-die, lip coater die, etc.
- the film discharged or cast uniformly on the peripheral surface of the rotating heated first roll (or belt) located on the upstream side and discharged or cast on the peripheral surface of the first roll (or belt) Volatile components are evaporated and dried from one side, and then further dried on the peripheral surface of one or more rotating heated rolls arranged downstream thereof, or in a hot air dryer
- the method of winding with a winding device can be preferably employed industrially. Drying with a heated roll and drying with a hot air dryer may be performed in an appropriate combination.
- the original film for producing an optical film of the present invention is used as an original film for producing an optical film.
- Examples of such an optical film include a polarizing film and a retardation film.
- Such an optical film can be produced, for example, by subjecting the raw film for producing an optical film of the present invention to a treatment such as uniaxial stretching.
- the method for producing a polarizing film using the original film for producing an optical film of the present invention is not particularly limited, and any conventionally employed method may be adopted.
- a method for example, dyeing and uniaxial stretching are performed on the original film for manufacturing an optical film of the present invention, or uniaxial stretching is performed on an original film for manufacturing an optical film of the present invention containing a dye.
- the method of giving is mentioned.
- the raw film for producing an optical film of the present invention is swelled, dyed, uniaxially stretched, and if necessary, further crosslinked, fixed, dried.
- a method of performing a heat treatment is not particularly limited, and one or two or more treatments can be performed simultaneously. Also, one or more of each process can be performed twice or more.
- Swelling can be performed by immersing the raw film for producing an optical film in water.
- the temperature of the water when immersed in water is preferably in the range of 20 to 40 ° C., more preferably in the range of 22 to 38 ° C., and preferably in the range of 25 to 35 ° C. Further preferred.
- the time for immersion in water is preferably in the range of 0.1 to 5 minutes, for example, and more preferably in the range of 0.5 to 3 minutes.
- the water at the time of immersing in water is not limited to pure water, The aqueous solution in which various components melt
- Dyeing can be performed by bringing a dichroic dye into contact with the original film for optical film production.
- a dichroic dye an iodine dye is generally used.
- the dyeing time may be any stage before uniaxial stretching, during uniaxial stretching, or after uniaxial stretching.
- Dyeing is generally carried out by immersing a raw film for optical film production in a solution (particularly an aqueous solution) containing iodine-potassium iodide as a dyeing bath. In the present invention, such a dyeing method is also used. Preferably employed.
- the iodine concentration in the dyeing bath is preferably in the range of 0.01 to 0.5% by mass, and the potassium iodide concentration is preferably in the range of 0.01 to 10% by mass.
- the temperature of the dyeing bath is preferably 20 to 50 ° C., particularly 25 to 40 ° C.
- the crosslinking treatment is preferably performed after the treatment for bringing the dichroic dye into contact and before the uniaxial stretching.
- the crosslinking treatment can be performed by immersing the raw film for producing an optical film in an aqueous solution containing a crosslinking agent.
- a crosslinking agent one or more of boron compounds such as boric acid and borate such as borax can be used.
- the concentration of the crosslinking agent in the aqueous solution containing the crosslinking agent is preferably in the range of 1 to 15% by mass, more preferably in the range of 2 to 7% by mass, and in the range of 3 to 6% by mass. More preferably. Sufficient stretchability can be maintained when the concentration of the crosslinking agent is in the range of 1 to 15% by mass.
- the aqueous solution containing a crosslinking agent may contain an auxiliary agent such as potassium iodide.
- the temperature of the aqueous solution containing the crosslinking agent is preferably in the range of 20 to 50 ° C., particularly in the range of 25 to 40 ° C. By setting the temperature within the range of 20 to 50 ° C., crosslinking can be performed efficiently.
- Uniaxial stretching may be performed by either a wet stretching method or a dry stretching method.
- the wet stretching method it can be carried out in an aqueous solution containing boric acid, or can be carried out in the dyeing bath described above or in a fixing treatment bath described later.
- the stretching may be performed at room temperature, may be performed while heating, or may be performed in the air using the raw film for producing an optical film after water absorption.
- the wet stretching method is preferable, and uniaxial stretching is more preferable in an aqueous solution containing boric acid.
- the concentration of boric acid in the boric acid aqueous solution is preferably within the range of 0.5 to 6.0% by mass, more preferably within the range of 1.0 to 5.0% by mass, It is particularly preferably within the range of ⁇ 4.0% by mass. Further, the aqueous boric acid solution may contain potassium iodide, and its concentration is preferably in the range of 0.01 to 10% by mass.
- the stretching temperature in the uniaxial stretching is preferably in the range of 30 to 90 ° C, more preferably in the range of 40 to 80 ° C, and particularly preferably in the range of 50 to 70 ° C.
- the draw ratio in uniaxial stretching is preferably 6.8 times or more, more preferably 6.9 times or more, and 7.0 times or more from the viewpoint of the polarizing performance of the obtained polarizing film. Is particularly preferred.
- the upper limit of the draw ratio is not particularly limited, but the draw ratio is preferably 8 times or less.
- Uniaxial stretching in the longitudinal direction is preferred because a film is obtained.
- Uniaxial stretching in the longitudinal direction can be performed by changing the peripheral speed between the rolls using a stretching apparatus including a plurality of rolls parallel to each other.
- lateral uniaxial stretching can be performed using a tenter type stretching machine.
- the fixing treatment bath used for the fixing treatment an aqueous solution containing one or more of boron compounds such as boric acid and borax can be used. Moreover, you may add an iodine compound and a metal compound in a fixed treatment bath as needed.
- the concentration of the boron compound in the fixing treatment bath is generally about 2 to 15% by mass, particularly about 3 to 10% by mass. By setting the concentration within the range of 2 to 15% by mass, the adsorption of the dichroic dye can be further strengthened.
- the temperature of the fixing treatment bath is preferably 15 to 60 ° C., particularly 25 to 40 ° C.
- Drying conditions are not particularly limited, but it is preferable to perform the drying at a temperature within the range of 30 to 150 ° C, particularly within the range of 50 to 130 ° C.
- a polarizing film excellent in dimensional stability can be easily obtained by drying at a temperature in the range of 30 to 150 ° C.
- the polarizing film obtained as described above is usually used as a polarizing plate by attaching an optically transparent protective film having mechanical strength to both sides or one side.
- an optically transparent protective film having mechanical strength to both sides or one side.
- a cellulose triacetate (TAC) film, an acetic acid / cellulose butyrate (CAB) film, an acrylic film, a polyester film, or the like is used as the protective film.
- the adhesive for bonding include PVA adhesives and urethane adhesives, among which PVA adhesives are suitable.
- the polarizing plate obtained as described above can be used as an LCD component after being coated with an acrylic adhesive or the like and bonded to a glass substrate. At the same time, it may be bonded to a retardation film, a viewing angle improving film, a brightness improving film, or the like.
- the width of the width 5 cm ⁇ length 5 cm is uniaxially stretched.
- a 5 cm ⁇ 8 cm long sample was cut. This sample was uniaxially stretched in the length direction by a factor of 1.5 while being immersed in pure water at 30 ° C. Subsequently, while being immersed in an aqueous solution (dyeing bath) (temperature 30 ° C.) containing 0.03% by mass of iodine and 3.0% by mass of potassium iodide for 60 seconds, the ratio is 1.6 times (2.4 in total). Uniaxially stretching in the length direction to adsorb iodine.
- the length was 1.1 times (2.6 times in total) while being immersed in an aqueous solution (crosslinking bath) (temperature 30 ° C.) containing 3% by weight of boric acid and 3% by weight of potassium iodide. Uniaxially stretched in the direction. Further, while being immersed in an aqueous solution (stretching bath) containing 4% by mass of boric acid and 6% by mass of potassium iodide, the film is uniaxially stretched in the length direction until it is cut, and the raw film for producing an optical film before stretching.
- the ratio of the length at the time of cutting with respect to the length of the film was defined as the limit stretch ratio.
- the temperature of the stretching bath was changed by 1 ° C. from an appropriate temperature, the limiting stretching ratio was measured, and the temperature at which the limiting stretching ratio was the highest was selected.
- Optical properties of polarizing film (dichroic ratio) (1) Measurement of transmittance Ts From the central part of the polarizing film obtained in the following examples or comparative examples, two 2 cm samples were taken in the length direction of the polarizing film, and a spectrophotometer with an integrating sphere (Japan) Using “V7100” manufactured by Spectroscopic Co., Ltd., in accordance with JIS Z 8722 (measuring method of object color), the visibility of the visible light region of the C light source and 2 ° field of view is corrected.
- the transmittance Ts (%) and the degree of polarization V (%) were determined by the method described above, and the transmittance Ts (%) was plotted on the horizontal axis and the degree of polarization for each example and comparative example.
- V (%) as the vertical axis, a total of 5 points including one point based on the transmittance Ts (%) and the degree of polarization V (%) of the polarizing film obtained in each example or comparative example are plotted on a graph.
- V (%) as the vertical axis
- a total of 5 points including one point based on the transmittance Ts (%) and the degree of polarization V (%) of the polarizing film obtained in each example or comparative example are plotted on a graph.
- an approximate curve was obtained, and from the approximate curve, the degree of polarization V 44 (%) when the transmittance Ts (%) was 44% was obtained.
- Example 1 100 parts by mass of a hydroxymethyl group-containing PVA shown in Table 1 obtained by saponifying a copolymer of vinyl acetate and 1,3-diacetoxy-2-methylenepropane as a modified PVA, and 10 parts by mass of glycerin as a plasticizer Part and an aqueous solution containing 0.1 part by weight of sodium polyoxyethylene lauryl ether sulfate as a surfactant and having a modified PVA content of 10% by weight as a film-forming stock solution.
- the film thus obtained was heat-treated at a predetermined temperature for 1 minute in a hot air dryer to adjust the degree of swelling to 200%, thereby producing an optical film-manufacturing raw film having a thickness of 30 ⁇ m.
- the stretchability was evaluated by the above-described method using the obtained optical film for optical film production. The results are shown in Table 1.
- the length was 1.1 times (2.6 times in total) while being immersed in an aqueous solution (crosslinking bath) (temperature 30 ° C.) containing 3% by weight of boric acid and 3% by weight of potassium iodide. Uniaxially stretched in the direction. Further, an aqueous solution (stretching bath) containing 4% by mass of boric acid and 6% by mass of potassium iodide (a temperature at which the limit stretching ratio determined in the above “stretchability of the raw film for producing optical film” becomes the highest) ) was uniaxially stretched in the length direction to a magnification 0.2 times lower than the limit draw ratio.
- Example 1 unmodified PVA shown in Table 1 obtained by saponifying a vinyl acetate homopolymer instead of modified PVA (Comparative Example 1); vinyl acetate and 3,4-diacetoxy-1 as modified PVA -Modified PVA obtained by saponifying a copolymer with butene (Comparative Example 2) shown in Table 1; or obtained by saponifying a copolymer of vinyl acetate and itaconic acid as modified PVA. Except that the modified PVA shown in Table 1 (Comparative Example 3) was used, a raw film for optical film production and a polarizing film were produced in the same manner as in Example 1, and each measurement or evaluation was performed. The results are shown in Table 1.
- Example 2 In Example 1, hydroxymethyl group-containing PVA shown in Table 1 obtained by saponifying a copolymer of vinyl acetate and 1,3-diacetoxy-2-methylenepropane as a modified PVA (Examples 2 and 3) Or a hydroxymethyl group-containing PVA shown in Table 1 (Example 4) obtained by saponifying a terpolymer of vinyl acetate, 1,3-diacetoxy-2-methylenepropane and ethylene as a modified PVA; Except having used each, the raw film for optical film manufacture and the polarizing film were manufactured similarly to Example 1, and each measurement or evaluation was performed. The results are shown in Table 1.
- the raw films for producing optical films of Examples 1 to 4 satisfying the rules of the present invention are excellent in stretchability and can be produced with high productivity.
- the stretchability is high, the area of the obtained optical film can be widened, and more optical films can be obtained.
- an optical film excellent in both optical properties and hue can be easily produced.
- Example 4 using the hydroxymethyl group-containing PVA further containing an ethylene unit the stretchability is further improved, the stretchable temperature is also increased, and it can be seen that the optical film can be produced with higher productivity.
Abstract
Description
[1]ビニルアルコール単位、及び下記式(1)で示される構造単位を含むヒドロキシメチル基含有PVAを含む、光学フィルム製造用原反フィルム; That is, the present invention
[1] A raw film for producing an optical film comprising a vinyl alcohol unit and a hydroxymethyl group-containing PVA containing a structural unit represented by the following formula (1);
[3]前記ヒドロキシメチル基含有PVAがエチレン単位をさらに含む、[1]または[2]に記載の光学フィルム製造用原反フィルム;
[4]前記ヒドロキシメチル基含有PVAにおけるエチレン単位の含有率が1~4モル%である、[3]に記載の光学フィルム製造用原反フィルム;
[5]前記ヒドロキシメチル基含有PVAのけん化度が95モル%以上である、[1]~[4]のいずれか1つに記載の光学フィルム製造用原反フィルム;
[6]偏光フィルム製造用原反フィルムである、[1]~[5]のいずれか1つに記載の光学フィルム製造用原反フィルム;
[7][1]~[6]のいずれか1つに記載の光学フィルム製造用原反フィルムを用いて一軸延伸する工程を有する、光学フィルムの製造方法;
に関する。 [2] The raw film for producing an optical film according to [1], wherein the content of the structural unit represented by the formula (1) in the hydroxymethyl group-containing PVA is 0.1 to 2 mol%;
[3] The raw film for producing an optical film according to [1] or [2], wherein the hydroxymethyl group-containing PVA further contains an ethylene unit;
[4] The raw film for producing an optical film according to [3], wherein the content of ethylene units in the hydroxymethyl group-containing PVA is 1 to 4 mol%;
[5] The raw film for producing an optical film according to any one of [1] to [4], wherein the saponification degree of the hydroxymethyl group-containing PVA is 95 mol% or more;
[6] The original film for producing an optical film according to any one of [1] to [5], which is an original film for producing a polarizing film;
[7] A method for producing an optical film, comprising a step of uniaxially stretching using the optical film-manufacturing raw film according to any one of [1] to [6];
About.
一軸延伸における延伸温度は、30~90℃の範囲内であることが好ましく、40~80℃の範囲内であることがより好ましく、50~70℃の範囲内であることが特に好ましい。
また、一軸延伸における延伸倍率は、得られる偏光フィルムの偏光性能の点から6.8倍以上であることが好ましく、6.9倍以上であることがより好ましく、7.0倍以上であることが特に好ましい。延伸倍率の上限は特に制限されないが、延伸倍率は8倍以下であることが好ましい。 Uniaxial stretching may be performed by either a wet stretching method or a dry stretching method. In the case of the wet stretching method, it can be carried out in an aqueous solution containing boric acid, or can be carried out in the dyeing bath described above or in a fixing treatment bath described later. In the case of the dry stretching method, the stretching may be performed at room temperature, may be performed while heating, or may be performed in the air using the raw film for producing an optical film after water absorption. Among these, the wet stretching method is preferable, and uniaxial stretching is more preferable in an aqueous solution containing boric acid. The concentration of boric acid in the boric acid aqueous solution is preferably within the range of 0.5 to 6.0% by mass, more preferably within the range of 1.0 to 5.0% by mass, It is particularly preferably within the range of ˜4.0% by mass. Further, the aqueous boric acid solution may contain potassium iodide, and its concentration is preferably in the range of 0.01 to 10% by mass.
The stretching temperature in the uniaxial stretching is preferably in the range of 30 to 90 ° C, more preferably in the range of 40 to 80 ° C, and particularly preferably in the range of 50 to 70 ° C.
Further, the draw ratio in uniaxial stretching is preferably 6.8 times or more, more preferably 6.9 times or more, and 7.0 times or more from the viewpoint of the polarizing performance of the obtained polarizing film. Is particularly preferred. The upper limit of the draw ratio is not particularly limited, but the draw ratio is preferably 8 times or less.
以下の実施例及び比較例で使用したPVA(実施例におけるヒドロキシメチル基含有PVAや比較例における各種変性PVA)の一次構造は、270MHz 1H-NMRを用いて分析した。1H-NMR測定時の溶媒は重水素化DMSOを用いた。 Primary structure of PVA The primary structure of PVA (hydroxymethyl group-containing PVA in Examples and various modified PVA in Comparative Examples) used in the following Examples and Comparative Examples was analyzed using 270 MHz 1 H-NMR. Deuterated DMSO was used as a solvent for the 1 H-NMR measurement.
以下の実施例または比較例で得られた光学フィルム製造用原反フィルムを1.5gとなるようにカットし、30℃の蒸留水中に30分間浸漬した。30分間浸漬後に当該フィルムを取り出し、ろ紙で表面の水を取り、質量「N」を求めた。続いてそのフィルムを105℃の乾燥機で16時間乾燥した後、質量「M」を求めた。得られた質量「N」及び「M」から、下記式(3)により光学フィルム製造用原反フィルムの膨潤度を算出した。
膨潤度(%) = 100 × N/M (3)
The degree of swelling of the raw film for optical film production The raw film for optical film production obtained in the following examples or comparative examples was cut to 1.5 g and immersed in distilled water at 30 ° C. for 30 minutes. After immersion for 30 minutes, the film was taken out, the surface water was taken out with a filter paper, and the mass “N” was determined. Subsequently, the film was dried with a dryer at 105 ° C. for 16 hours, and then the mass “M” was determined. From the obtained masses “N” and “M”, the degree of swelling of the raw film for optical film production was calculated by the following formula (3).
Swelling degree (%) = 100 × N / M (3)
以下の実施例または比較例で得られた光学フィルム製造用原反フィルムの幅方向中央部から、幅5cm×長さ5cmの範囲が一軸延伸できるように幅5cm×長さ8cmのサンプルをカットした。このサンプルを30℃の純水に浸漬しつつ1.5倍に長さ方向に一軸延伸した。続いてヨウ素を0.03質量%及びヨウ化カリウムを3.0質量%の割合で含有する水溶液(染色浴)(温度30℃)に60秒間浸漬しつつ1.6倍(全体で2.4倍)に長さ方向に一軸延伸してヨウ素を吸着させた。次いで、ホウ酸を3質量%及びヨウ化カリウムを3質量%の割合で含有する水溶液(架橋浴)(温度30℃)に浸漬しつつ1.1倍(全体で2.6倍)に長さ方向に一軸延伸した。さらにホウ酸を4質量%及びヨウ化カリウムを6質量%の割合で含有する水溶液(延伸浴)に浸漬しつつ、切断するまで長さ方向に一軸延伸し、延伸前の光学フィルム製造用原反フィルムの長さに対する切断時の長さの倍率を限界延伸倍率とした。ただし、延伸浴の温度については、適当な温度から1℃ずつ変更して限界延伸倍率を測定し、限界延伸倍率が最も高くなる温度を選択した。 Stretchability of the optical film production raw film From the center in the width direction of the optical film production raw film obtained in the following examples or comparative examples, the width of the width 5 cm × length 5 cm is uniaxially stretched. A 5 cm × 8 cm long sample was cut. This sample was uniaxially stretched in the length direction by a factor of 1.5 while being immersed in pure water at 30 ° C. Subsequently, while being immersed in an aqueous solution (dyeing bath) (temperature 30 ° C.) containing 0.03% by mass of iodine and 3.0% by mass of potassium iodide for 60 seconds, the ratio is 1.6 times (2.4 in total). Uniaxially stretching in the length direction to adsorb iodine. Next, the length was 1.1 times (2.6 times in total) while being immersed in an aqueous solution (crosslinking bath) (temperature 30 ° C.) containing 3% by weight of boric acid and 3% by weight of potassium iodide. Uniaxially stretched in the direction. Further, while being immersed in an aqueous solution (stretching bath) containing 4% by mass of boric acid and 6% by mass of potassium iodide, the film is uniaxially stretched in the length direction until it is cut, and the raw film for producing an optical film before stretching. The ratio of the length at the time of cutting with respect to the length of the film was defined as the limit stretch ratio. However, the temperature of the stretching bath was changed by 1 ° C. from an appropriate temperature, the limiting stretching ratio was measured, and the temperature at which the limiting stretching ratio was the highest was selected.
(1)透過率Tsの測定
以下の実施例または比較例で得られた偏光フィルムの中央部から、偏光フィルムの長さ方向に2cmのサンプルを2枚採取し、積分球付き分光光度計(日本分光株式会社製「V7100」)を用いて、JIS Z 8722(物体色の測定方法)に準拠し、C光源、2°視野の可視光領域の視感度補正を行い、1枚のサンプルについて、長さ方向に対して+45°傾けた場合の光の透過率と-45°傾けた場合の光の透過率を測定して、それらの平均値Ts1(%)を求めた。もう1枚のサンプルについても同様にして、+45°傾けた場合の光の透過率と-45°傾けた場合の光の透過率を測定して、それらの平均値Ts2(%)を求めた。下記式(4)によりTs1とTs2を平均し、偏光フィルムの透過率Ts(%)とした。
Ts = (Ts1+Ts2)/2 (4)
Optical properties of polarizing film (dichroic ratio)
(1) Measurement of transmittance Ts From the central part of the polarizing film obtained in the following examples or comparative examples, two 2 cm samples were taken in the length direction of the polarizing film, and a spectrophotometer with an integrating sphere (Japan) Using “V7100” manufactured by Spectroscopic Co., Ltd., in accordance with JIS Z 8722 (measuring method of object color), the visibility of the visible light region of the C light source and 2 ° field of view is corrected. The light transmittance when tilted by + 45 ° with respect to the vertical direction and the light transmittance when tilted by −45 ° were measured, and an average value Ts1 (%) thereof was obtained. Similarly, with respect to the other sample, the light transmittance when tilted by + 45 ° and the light transmittance when tilted by −45 ° were measured, and an average value Ts2 (%) thereof was obtained. Ts1 and Ts2 were averaged by the following formula (4) to obtain the transmittance Ts (%) of the polarizing film.
Ts = (Ts1 + Ts2) / 2 (4)
上記透過率Tsの測定で採取した2枚のサンプルを、その長さ方向が平行になるように重ねた場合の光の透過率T∥(%)、長さ方向が直交するように重ねた場合の光の透過率T⊥(%)を、上記「(1)透過率Tsの測定」の場合と同様にして測定し、下記式(5)により偏光度V(%)を求めた。
V = {(T∥-T⊥)/(T∥+T⊥)}1/2×100 (5)
(2) Measurement of degree of polarization V Light transmittance T∥ (%) and length direction when two samples collected in the measurement of transmittance Ts are stacked so that their length directions are parallel. Are measured in the same manner as in the case of “(1) Measurement of transmittance Ts”, and the degree of polarization V ( %).
V = {(T∥−T⊥) / (T∥ + T⊥)} 1/2 × 100 (5)
以下の各実施例及び比較例において、染色浴におけるヨウ素の濃度を0.02~0.04質量%及びヨウ化カリウムの濃度を2.0~4.0質量%の各範囲内で4回変更(ただし、ヨウ素の濃度:ヨウ化カリウムの濃度=1:100とする)して同様の操作を行い、各実施例または比較例で製造した偏光フィルムとは二色性色素の吸着量の異なる4枚の偏光フィルムを製造した。これら4枚の偏光フィルムのそれぞれについて上記した方法で透過率Ts(%)及び偏光度V(%)を求め、各実施例及び比較例毎に、透過率Ts(%)を横軸、偏光度V(%)を縦軸として、各実施例または比較例で得られた偏光フィルムの透過率Ts(%)及び偏光度V(%)に基づく1点も含めた合計5点をグラフにプロットして近似曲線を求め、当該近似曲線から、透過率Ts(%)が44%であるときの偏光度V44(%)を求めた。
得られた偏光度V44(%)から、下記式(6)により透過率44%時の二色性比を求めて、偏光性能の指標とした。
透過率44%時の二色性比 = log(44/100-44/100×V44/100)/log(44/100+44/100×V44/100) (6)
(3) Calculation of dichroic ratio when transmittance is 44% In each of the following Examples and Comparative Examples, the iodine concentration in the dyeing bath is 0.02 to 0.04% by mass, and the potassium iodide concentration is 2. The same operation was carried out by changing 4 times within the range of 0 to 4.0% by mass (however, the concentration of iodine: concentration of potassium iodide = 1: 100). Four polarizing films having different dichroic dye adsorption amounts were produced. For each of these four polarizing films, the transmittance Ts (%) and the degree of polarization V (%) were determined by the method described above, and the transmittance Ts (%) was plotted on the horizontal axis and the degree of polarization for each example and comparative example. With V (%) as the vertical axis, a total of 5 points including one point based on the transmittance Ts (%) and the degree of polarization V (%) of the polarizing film obtained in each example or comparative example are plotted on a graph. Thus, an approximate curve was obtained, and from the approximate curve, the degree of polarization V 44 (%) when the transmittance Ts (%) was 44% was obtained.
From the obtained degree of polarization V 44 (%), the dichroic ratio at a transmittance of 44% was determined by the following formula (6) and used as an index of polarization performance.
Dichroic ratio when the transmittance 44% = log (44 / 100-44 / 100 × V 44/100) / log (44/100 + 44/100 × V 44/100) (6)
上記の「偏光フィルムの光学特性(二色性比)」において、二色性色素の吸着量の異なる4枚の偏光フィルムの偏光度Vを求める際に、透過率T∥(%)及び透過率T⊥(%)測定時にLabを測定し、透過率T∥(%)の測定時のb値を平行b値とし、透過率T⊥(%)の測定時のb値を直交b値とした。各実施例及び比較例毎に、平行b値を横軸、直交b値を縦軸として、各実施例または比較例で得られた偏光フィルムの平行b値及び直交b値に基づく1点も含めた合計5点をグラフにプロットして近似曲線を求め、当該近似曲線から、直交b値が-4であるときの平行b値を求めた。なお、平行b値が0に近いほど、偏光フィルムの色相は良好であるとした。 Color of polarizing film (parallel b value)
In the above-mentioned “optical properties of the polarizing film (dichroic ratio)”, the transmittance T∥ (%) and the transmittance are obtained when the degree of polarization V of the four polarizing films having different dichroic dye adsorption amounts is obtained. Lab was measured at the time of measuring T⊥ (%), b value at the time of measuring transmittance T∥ (%) was taken as a parallel b value, and b value at the time of measuring transmittance T⊥ (%) was taken as an orthogonal b value. . For each example and comparative example, including the parallel b value as the horizontal axis and the orthogonal b value as the vertical axis, including one point based on the parallel b value and orthogonal b value of the polarizing film obtained in each example or comparative example A total of 5 points were plotted on a graph to obtain an approximate curve, and a parallel b value when the orthogonal b value was −4 was obtained from the approximate curve. Note that the closer the parallel b value is to 0, the better the hue of the polarizing film.
(1)変性PVAとして酢酸ビニルと1,3-ジアセトキシ-2-メチレンプロパンとの共重合体をけん化することにより得られた表1に示すヒドロキシメチル基含有PVA100質量部、可塑剤としてグリセリン10質量部、及び界面活性剤としてポリオキシエチレンラウリルエーテル硫酸ナトリウム0.1質量部を含み、変性PVAの含有率が10質量%である水溶液を製膜原液として用いて、これを80℃の金属ロール上で乾燥し、得られたフィルムを熱風乾燥機中で所定の温度で1分間熱処理をすることにより膨潤度を200%に調整して、厚みが30μmの光学フィルム製造用原反フィルムを製造した。
得られた光学フィルム製造用原反フィルムを用いて、上記した方法により延伸性を評価した。結果を表1に示した。 [Example 1]
(1) 100 parts by mass of a hydroxymethyl group-containing PVA shown in Table 1 obtained by saponifying a copolymer of vinyl acetate and 1,3-diacetoxy-2-methylenepropane as a modified PVA, and 10 parts by mass of glycerin as a plasticizer Part and an aqueous solution containing 0.1 part by weight of sodium polyoxyethylene lauryl ether sulfate as a surfactant and having a modified PVA content of 10% by weight as a film-forming stock solution. The film thus obtained was heat-treated at a predetermined temperature for 1 minute in a hot air dryer to adjust the degree of swelling to 200%, thereby producing an optical film-manufacturing raw film having a thickness of 30 μm.
The stretchability was evaluated by the above-described method using the obtained optical film for optical film production. The results are shown in Table 1.
得られた偏光フィルムを用いて、上記した方法により偏光フィルムの光学特性(二色性比)及び色相(平行b値)を評価した。結果を表1に示した。 (2) A sample having a width of 5 cm and a length of 8 cm was cut from the central portion in the width direction of the original film for producing an optical film obtained in (1) so that a range of width 5 cm × length 5 cm could be uniaxially stretched. . This sample was uniaxially stretched in the length direction by a factor of 1.5 while being immersed in pure water at 30 ° C. Subsequently, while being immersed in an aqueous solution (dyeing bath) (temperature 30 ° C.) containing 0.03% by mass of iodine and 3.0% by mass of potassium iodide for 60 seconds, the ratio is 1.6 times (2.4 in total). Uniaxially stretching in the length direction to adsorb iodine. Next, the length was 1.1 times (2.6 times in total) while being immersed in an aqueous solution (crosslinking bath) (temperature 30 ° C.) containing 3% by weight of boric acid and 3% by weight of potassium iodide. Uniaxially stretched in the direction. Further, an aqueous solution (stretching bath) containing 4% by mass of boric acid and 6% by mass of potassium iodide (a temperature at which the limit stretching ratio determined in the above “stretchability of the raw film for producing optical film” becomes the highest) ) Was uniaxially stretched in the length direction to a magnification 0.2 times lower than the limit draw ratio. Thereafter, it was immersed in an aqueous solution (cleaning bath) containing 3% by mass of potassium iodide (temperature 30 ° C.) for 5 seconds, and finally dried at 60 ° C. for 4 minutes to produce a polarizing film.
Using the obtained polarizing film, the optical properties (dichroic ratio) and hue (parallel b value) of the polarizing film were evaluated by the method described above. The results are shown in Table 1.
実施例1において、変性PVAの代わりに酢酸ビニルの単独重合体をけん化することにより得られた表1に示す未変性PVA(比較例1);変性PVAとして酢酸ビニルと3,4-ジアセトキシ-1-ブテンとの共重合体をけん化することにより得られた表1に示す変性PVA(比較例2);または、変性PVAとして酢酸ビニルとイタコン酸との共重合体をけん化することにより得られた表1に示す変性PVA(比較例3)をそれそれ用いたこと以外は、実施例1と同様にして光学フィルム製造用原反フィルム及び偏光フィルムを製造して、各測定または評価を行った。結果を表1に示した。 [Comparative Examples 1 to 3]
In Example 1, unmodified PVA shown in Table 1 obtained by saponifying a vinyl acetate homopolymer instead of modified PVA (Comparative Example 1); vinyl acetate and 3,4-diacetoxy-1 as modified PVA -Modified PVA obtained by saponifying a copolymer with butene (Comparative Example 2) shown in Table 1; or obtained by saponifying a copolymer of vinyl acetate and itaconic acid as modified PVA. Except that the modified PVA shown in Table 1 (Comparative Example 3) was used, a raw film for optical film production and a polarizing film were produced in the same manner as in Example 1, and each measurement or evaluation was performed. The results are shown in Table 1.
実施例1において、変性PVAとして酢酸ビニルと1,3-ジアセトキシ-2-メチレンプロパンとの共重合体をけん化することにより得られた表1に示すヒドロキシメチル基含有PVA(実施例2及び3);または、変性PVAとして酢酸ビニルと1,3-ジアセトキシ-2-メチレンプロパンとエチレンの3元共重合体をけん化することにより得られた表1に示すヒドロキシメチル基含有PVA(実施例4)をそれぞれ用いたこと以外は、実施例1と同様にして光学フィルム製造用原反フィルム及び偏光フィルムを製造して、各測定または評価を行った。結果を表1に示した。 [Examples 2 to 4]
In Example 1, hydroxymethyl group-containing PVA shown in Table 1 obtained by saponifying a copolymer of vinyl acetate and 1,3-diacetoxy-2-methylenepropane as a modified PVA (Examples 2 and 3) Or a hydroxymethyl group-containing PVA shown in Table 1 (Example 4) obtained by saponifying a terpolymer of vinyl acetate, 1,3-diacetoxy-2-methylenepropane and ethylene as a modified PVA; Except having used each, the raw film for optical film manufacture and the polarizing film were manufactured similarly to Example 1, and each measurement or evaluation was performed. The results are shown in Table 1.
Claims (7)
- 前記ヒドロキシメチル基含有ビニルアルコール系重合体における前記式(1)で示される構造単位の含有率が0.1~2モル%である、請求項1に記載の光学フィルム製造用原反フィルム。 2. The raw film for producing an optical film according to claim 1, wherein the content of the structural unit represented by the formula (1) in the hydroxymethyl group-containing vinyl alcohol polymer is 0.1 to 2 mol%.
- 前記ヒドロキシメチル基含有ビニルアルコール系重合体がエチレン単位をさらに含む、請求項1または2に記載の光学フィルム製造用原反フィルム。 The raw film for producing an optical film according to claim 1 or 2, wherein the hydroxymethyl group-containing vinyl alcohol polymer further comprises an ethylene unit.
- 前記ヒドロキシメチル基含有ビニルアルコール系重合体におけるエチレン単位の含有率が1~4モル%である、請求項3に記載の光学フィルム製造用原反フィルム。 4. The raw film for producing an optical film according to claim 3, wherein the content of ethylene units in the hydroxymethyl group-containing vinyl alcohol polymer is 1 to 4 mol%.
- 前記ヒドロキシメチル基含有ビニルアルコール系重合体のけん化度が95モル%以上である、請求項1~4のいずれか1項に記載の光学フィルム製造用原反フィルム。 The raw film for producing an optical film according to any one of claims 1 to 4, wherein the hydroxymethyl group-containing vinyl alcohol polymer has a saponification degree of 95 mol% or more.
- 偏光フィルム製造用原反フィルムである、請求項1~5のいずれか1項に記載の光学フィルム製造用原反フィルム。 The optical film-producing original film according to any one of claims 1 to 5, which is a polarizing film-producing original film.
- 請求項1~6のいずれか1項に記載の光学フィルム製造用原反フィルムを用いて一軸延伸する工程を有する、光学フィルムの製造方法。 A method for producing an optical film, comprising a step of uniaxially stretching using the raw film for producing an optical film according to any one of claims 1 to 6.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020167003438A KR102161870B1 (en) | 2013-08-09 | 2014-08-05 | Original film for manufacturing optical film |
CN201480042988.6A CN105408783B (en) | 2013-08-09 | 2014-08-05 | Optical film manufacture initial film |
JP2014553566A JP6383664B2 (en) | 2013-08-09 | 2014-08-05 | Raw film for optical film production |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2013-165993 | 2013-08-09 | ||
JP2013165993 | 2013-08-09 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2015020044A1 true WO2015020044A1 (en) | 2015-02-12 |
Family
ID=52461375
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2014/070603 WO2015020044A1 (en) | 2013-08-09 | 2014-08-05 | Original film for manufacturing optical film |
Country Status (5)
Country | Link |
---|---|
JP (1) | JP6383664B2 (en) |
KR (1) | KR102161870B1 (en) |
CN (1) | CN105408783B (en) |
TW (1) | TWI636066B (en) |
WO (1) | WO2015020044A1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2016121507A1 (en) * | 2015-01-27 | 2016-08-04 | 株式会社クラレ | Film |
WO2016121508A1 (en) * | 2015-01-27 | 2016-08-04 | 株式会社クラレ | Film |
JPWO2015020045A1 (en) * | 2013-08-09 | 2017-03-02 | 株式会社クラレ | the film |
JPWO2018164196A1 (en) * | 2017-03-08 | 2020-01-09 | 株式会社クラレ | Polarizing film, polarizing plate, and manufacturing method thereof |
WO2021132435A1 (en) * | 2019-12-26 | 2021-07-01 | 株式会社クラレ | Polyvinyl alcohol film and polarizing film |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2019189687A1 (en) * | 2018-03-30 | 2019-10-03 | 積水化学工業株式会社 | Poly(vinyl alcohol) film and production method for polarizing film |
CN110441853B (en) * | 2019-08-14 | 2021-07-13 | 佛山纬达光电材料股份有限公司 | Xenon-lamp-resistant test polarizer and preparation method thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5399334A (en) * | 1977-02-08 | 1978-08-30 | Bayer Ag | Antiitumor agent |
JP2013177576A (en) * | 2012-02-10 | 2013-09-09 | Kuraray Co Ltd | Hydroxymethyl group-containing vinyl alcohol-based polymer |
Family Cites Families (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2047249A1 (en) * | 1970-09-25 | 1972-03-30 | Bayer | Process for the production of acrylonitrile copolymers |
DE2332562A1 (en) * | 1973-06-27 | 1975-01-23 | Agfa Gevaert Ag | PHOTOGRAPHIC MATERIAL WITH IMPROVED PROPERTIES |
US5070126A (en) * | 1988-08-02 | 1991-12-03 | Aicello Chemical Co., Ltd. | Films easily soluble in cold water |
JPH04164998A (en) * | 1990-10-29 | 1992-06-10 | Lion Corp | Detergent in item packaging form |
CA2135895A1 (en) * | 1992-05-21 | 1993-11-25 | Sigrun Eriksen | Copolymers and detergent compositions containing them |
JP3497903B2 (en) * | 1995-01-23 | 2004-02-16 | 株式会社クラレ | Polyvinyl alcohol film for raw material of polarizing film |
JP3657360B2 (en) * | 1996-07-10 | 2005-06-08 | 株式会社クラレ | Formulation composition and adhesive |
JPH11198304A (en) * | 1998-01-20 | 1999-07-27 | Kuraray Co Ltd | Thermoforming multilayer structure and thermoformed vessel |
JP2002060636A (en) * | 2000-08-23 | 2002-02-26 | Dainippon Ink & Chem Inc | Photocuring resin composition, photocuring sheet material, and method for their use |
JP5079184B2 (en) * | 2000-12-06 | 2012-11-21 | 株式会社クラレ | Polarized film |
DE60201142T2 (en) * | 2001-04-20 | 2005-10-20 | Kuraray Co., Ltd., Kurashiki | Water-soluble film and packaging using same |
KR100508822B1 (en) * | 2002-03-20 | 2005-08-17 | 가부시키가이샤 구라레 | Polyvinyl alc0h0l film |
JP4800269B2 (en) * | 2007-07-19 | 2011-10-26 | 日本合成化学工業株式会社 | Polyvinyl alcohol film for polarizing film, polarizing film, and polarizing plate |
KR101752027B1 (en) * | 2010-04-20 | 2017-06-28 | 주식회사 쿠라레 | Polyvinyl alcohol film |
JP6017773B2 (en) * | 2011-10-31 | 2016-11-02 | 株式会社クラレ | Manufacturing method of polarizing film |
JP5909811B2 (en) * | 2012-08-09 | 2016-04-27 | 株式会社クラレ | Modified ethylene-vinyl alcohol copolymer and multilayer structure |
WO2015020045A1 (en) * | 2013-08-09 | 2015-02-12 | 株式会社クラレ | Film |
-
2014
- 2014-08-05 JP JP2014553566A patent/JP6383664B2/en active Active
- 2014-08-05 WO PCT/JP2014/070603 patent/WO2015020044A1/en active Application Filing
- 2014-08-05 KR KR1020167003438A patent/KR102161870B1/en active IP Right Grant
- 2014-08-05 CN CN201480042988.6A patent/CN105408783B/en active Active
- 2014-08-07 TW TW103127012A patent/TWI636066B/en active
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5399334A (en) * | 1977-02-08 | 1978-08-30 | Bayer Ag | Antiitumor agent |
JP2013177576A (en) * | 2012-02-10 | 2013-09-09 | Kuraray Co Ltd | Hydroxymethyl group-containing vinyl alcohol-based polymer |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2015020045A1 (en) * | 2013-08-09 | 2017-03-02 | 株式会社クラレ | the film |
WO2016121507A1 (en) * | 2015-01-27 | 2016-08-04 | 株式会社クラレ | Film |
WO2016121508A1 (en) * | 2015-01-27 | 2016-08-04 | 株式会社クラレ | Film |
JPWO2016121507A1 (en) * | 2015-01-27 | 2017-11-02 | 株式会社クラレ | the film |
JPWO2016121508A1 (en) * | 2015-01-27 | 2017-11-09 | 株式会社クラレ | the film |
JPWO2018164196A1 (en) * | 2017-03-08 | 2020-01-09 | 株式会社クラレ | Polarizing film, polarizing plate, and manufacturing method thereof |
JP7199343B2 (en) | 2017-03-08 | 2023-01-05 | 株式会社クラレ | Polarizing film, polarizing plate, and manufacturing method thereof |
WO2021132435A1 (en) * | 2019-12-26 | 2021-07-01 | 株式会社クラレ | Polyvinyl alcohol film and polarizing film |
Also Published As
Publication number | Publication date |
---|---|
KR102161870B1 (en) | 2020-10-05 |
JPWO2015020044A1 (en) | 2017-03-02 |
CN105408783B (en) | 2018-04-03 |
TWI636066B (en) | 2018-09-21 |
TW201509955A (en) | 2015-03-16 |
KR20160041921A (en) | 2016-04-18 |
CN105408783A (en) | 2016-03-16 |
JP6383664B2 (en) | 2018-08-29 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6420153B2 (en) | Vinyl alcohol polymer film | |
JP6383664B2 (en) | Raw film for optical film production | |
JP6408989B2 (en) | Raw film for optical film production | |
JP6788673B2 (en) | Polarizing film and its manufacturing method | |
WO2021070622A1 (en) | Film for production of optical film, method for producing optical film, and optical film | |
JP5931125B2 (en) | Manufacturing method of polarizing film | |
JP2016222834A (en) | Method for producing polyvinyl alcohol film | |
JP6858499B2 (en) | Optical film manufacturing method | |
JP5606704B2 (en) | Manufacturing method of polarizing film | |
JP6776129B2 (en) | the film | |
JP6255300B2 (en) | Method for producing polyvinyl alcohol resin | |
JP6792456B2 (en) | the film | |
JP2023056678A (en) | Polyvinyl alcohol film, method of producing polyvinyl alcohol film, stretched film and polarizing film |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 201480042988.6 Country of ref document: CN |
|
ENP | Entry into the national phase |
Ref document number: 2014553566 Country of ref document: JP Kind code of ref document: A |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 14833665 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 20167003438 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: 14833665 Country of ref document: EP Kind code of ref document: A1 |