CN119019737A - Polyvinyl alcohol film and optical film made therefrom - Google Patents
Polyvinyl alcohol film and optical film made therefrom Download PDFInfo
- Publication number
- CN119019737A CN119019737A CN202310658893.8A CN202310658893A CN119019737A CN 119019737 A CN119019737 A CN 119019737A CN 202310658893 A CN202310658893 A CN 202310658893A CN 119019737 A CN119019737 A CN 119019737A
- Authority
- CN
- China
- Prior art keywords
- polyvinyl alcohol
- film
- alcohol film
- degree
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000010408 film Substances 0.000 title claims abstract description 281
- 229920002451 polyvinyl alcohol Polymers 0.000 title claims abstract description 236
- 239000004372 Polyvinyl alcohol Substances 0.000 title claims abstract description 232
- 239000012788 optical film Substances 0.000 title claims abstract description 32
- 230000008961 swelling Effects 0.000 claims abstract description 91
- 229920005989 resin Polymers 0.000 claims abstract description 58
- 239000011347 resin Substances 0.000 claims abstract description 58
- 230000010287 polarization Effects 0.000 claims abstract description 45
- 239000004327 boric acid Substances 0.000 claims abstract description 37
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 claims abstract description 35
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 34
- 238000003860 storage Methods 0.000 claims abstract description 18
- 238000006116 polymerization reaction Methods 0.000 claims description 17
- 238000010438 heat treatment Methods 0.000 claims description 13
- 206010042674 Swelling Diseases 0.000 description 78
- 238000000034 method Methods 0.000 description 41
- NLKNQRATVPKPDG-UHFFFAOYSA-M potassium iodide Chemical compound [K+].[I-] NLKNQRATVPKPDG-UHFFFAOYSA-M 0.000 description 30
- 230000008569 process Effects 0.000 description 29
- 239000000243 solution Substances 0.000 description 29
- 238000005266 casting Methods 0.000 description 28
- 238000004090 dissolution Methods 0.000 description 28
- 238000001035 drying Methods 0.000 description 25
- 238000004043 dyeing Methods 0.000 description 18
- 230000000052 comparative effect Effects 0.000 description 14
- 239000013078 crystal Substances 0.000 description 14
- -1 polyethylene Polymers 0.000 description 13
- 238000002791 soaking Methods 0.000 description 13
- 239000007864 aqueous solution Substances 0.000 description 12
- 238000011156 evaluation Methods 0.000 description 12
- 230000000694 effects Effects 0.000 description 11
- 230000008859 change Effects 0.000 description 10
- 238000004519 manufacturing process Methods 0.000 description 10
- 238000004458 analytical method Methods 0.000 description 9
- 230000006866 deterioration Effects 0.000 description 9
- 239000002245 particle Substances 0.000 description 9
- 239000000047 product Substances 0.000 description 9
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 8
- 239000011630 iodine Substances 0.000 description 8
- 229910052740 iodine Inorganic materials 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 239000004014 plasticizer Substances 0.000 description 8
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 7
- 238000010306 acid treatment Methods 0.000 description 7
- 239000000654 additive Substances 0.000 description 7
- RTZKZFJDLAIYFH-UHFFFAOYSA-N ether Substances CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- 238000005406 washing Methods 0.000 description 7
- 230000007423 decrease Effects 0.000 description 6
- 239000006185 dispersion Substances 0.000 description 6
- 239000011241 protective layer Substances 0.000 description 6
- 229920003171 Poly (ethylene oxide) Polymers 0.000 description 5
- 230000001276 controlling effect Effects 0.000 description 5
- 230000000670 limiting effect Effects 0.000 description 5
- 238000002360 preparation method Methods 0.000 description 5
- 239000004698 Polyethylene Substances 0.000 description 4
- 230000000996 additive effect Effects 0.000 description 4
- 230000015556 catabolic process Effects 0.000 description 4
- 238000006731 degradation reaction Methods 0.000 description 4
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 4
- 239000011521 glass Substances 0.000 description 4
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 description 4
- 229920000573 polyethylene Polymers 0.000 description 4
- 239000011265 semifinished product Substances 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- 229920001567 vinyl ester resin Polymers 0.000 description 4
- UAYWVJHJZHQCIE-UHFFFAOYSA-L zinc iodide Chemical compound I[Zn]I UAYWVJHJZHQCIE-UHFFFAOYSA-L 0.000 description 4
- 229920002284 Cellulose triacetate Polymers 0.000 description 3
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 3
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 3
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical compound CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 description 3
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 3
- NNLVGZFZQQXQNW-ADJNRHBOSA-N [(2r,3r,4s,5r,6s)-4,5-diacetyloxy-3-[(2s,3r,4s,5r,6r)-3,4,5-triacetyloxy-6-(acetyloxymethyl)oxan-2-yl]oxy-6-[(2r,3r,4s,5r,6s)-4,5,6-triacetyloxy-2-(acetyloxymethyl)oxan-3-yl]oxyoxan-2-yl]methyl acetate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](OC(C)=O)[C@H]1OC(C)=O)O[C@H]1[C@@H]([C@@H](OC(C)=O)[C@H](OC(C)=O)[C@@H](COC(C)=O)O1)OC(C)=O)COC(=O)C)[C@@H]1[C@@H](COC(C)=O)O[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@H]1OC(C)=O NNLVGZFZQQXQNW-ADJNRHBOSA-N 0.000 description 3
- 230000003750 conditioning effect Effects 0.000 description 3
- 238000002425 crystallisation Methods 0.000 description 3
- 230000008025 crystallization Effects 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 235000011187 glycerol Nutrition 0.000 description 3
- 239000000178 monomer Substances 0.000 description 3
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 3
- 230000002829 reductive effect Effects 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 3
- 239000004094 surface-active agent Substances 0.000 description 3
- 230000007704 transition Effects 0.000 description 3
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 2
- BAPJBEWLBFYGME-UHFFFAOYSA-N Methyl acrylate Chemical compound COC(=O)C=C BAPJBEWLBFYGME-UHFFFAOYSA-N 0.000 description 2
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 description 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 2
- 150000001252 acrylic acid derivatives Chemical class 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 229920006026 co-polymeric resin Polymers 0.000 description 2
- ILRSCQWREDREME-UHFFFAOYSA-N dodecanamide Chemical compound CCCCCCCCCCCC(N)=O ILRSCQWREDREME-UHFFFAOYSA-N 0.000 description 2
- 150000004694 iodide salts Chemical class 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 229920001451 polypropylene glycol Polymers 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 229940057950 sodium laureth sulfate Drugs 0.000 description 2
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 2
- SXHLENDCVBIJFO-UHFFFAOYSA-M sodium;2-[2-(2-dodecoxyethoxy)ethoxy]ethyl sulfate Chemical compound [Na+].CCCCCCCCCCCCOCCOCCOCCOS([O-])(=O)=O SXHLENDCVBIJFO-UHFFFAOYSA-M 0.000 description 2
- 238000007655 standard test method Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000002834 transmittance Methods 0.000 description 2
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 description 2
- KAKVFSYQVNHFBS-UHFFFAOYSA-N (5-hydroxycyclopenten-1-yl)-phenylmethanone Chemical compound OC1CCC=C1C(=O)C1=CC=CC=C1 KAKVFSYQVNHFBS-UHFFFAOYSA-N 0.000 description 1
- PIIRYSWVJSPXMW-UHFFFAOYSA-N 1-octyl-4-(4-octylphenoxy)benzene Chemical compound C1=CC(CCCCCCCC)=CC=C1OC1=CC=C(CCCCCCCC)C=C1 PIIRYSWVJSPXMW-UHFFFAOYSA-N 0.000 description 1
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 239000004925 Acrylic resin Substances 0.000 description 1
- 229920000178 Acrylic resin Polymers 0.000 description 1
- RPNUMPOLZDHAAY-UHFFFAOYSA-N Diethylenetriamine Chemical compound NCCNCCN RPNUMPOLZDHAAY-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- JIGUQPWFLRLWPJ-UHFFFAOYSA-N Ethyl acrylate Chemical compound CCOC(=O)C=C JIGUQPWFLRLWPJ-UHFFFAOYSA-N 0.000 description 1
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 description 1
- DKNPRRRKHAEUMW-UHFFFAOYSA-N Iodine aqueous Chemical compound [K+].I[I-]I DKNPRRRKHAEUMW-UHFFFAOYSA-N 0.000 description 1
- AOMUHOFOVNGZAN-UHFFFAOYSA-N N,N-bis(2-hydroxyethyl)dodecanamide Chemical compound CCCCCCCCCCCC(=O)N(CCO)CCO AOMUHOFOVNGZAN-UHFFFAOYSA-N 0.000 description 1
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 1
- 229930182556 Polyacetal Natural products 0.000 description 1
- 239000004962 Polyamide-imide Substances 0.000 description 1
- 239000004695 Polyether sulfone Substances 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- 229920001328 Polyvinylidene chloride Polymers 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- UWHCKJMYHZGTIT-UHFFFAOYSA-N Tetraethylene glycol, Natural products OCCOCCOCCOCCO UWHCKJMYHZGTIT-UHFFFAOYSA-N 0.000 description 1
- ZJCCRDAZUWHFQH-UHFFFAOYSA-N Trimethylolpropane Chemical compound CCC(CO)(CO)CO ZJCCRDAZUWHFQH-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- XECAHXYUAAWDEL-UHFFFAOYSA-N acrylonitrile butadiene styrene Chemical compound C=CC=C.C=CC#N.C=CC1=CC=CC=C1 XECAHXYUAAWDEL-UHFFFAOYSA-N 0.000 description 1
- 229920000122 acrylonitrile butadiene styrene Polymers 0.000 description 1
- 239000004676 acrylonitrile butadiene styrene Substances 0.000 description 1
- 229920001893 acrylonitrile styrene Polymers 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 150000003973 alkyl amines Chemical class 0.000 description 1
- 125000005907 alkyl ester group Chemical group 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 239000003945 anionic surfactant Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- CQEYYJKEWSMYFG-UHFFFAOYSA-N butyl acrylate Chemical compound CCCCOC(=O)C=C CQEYYJKEWSMYFG-UHFFFAOYSA-N 0.000 description 1
- 150000007942 carboxylates Chemical class 0.000 description 1
- 125000002091 cationic group Chemical group 0.000 description 1
- 239000003093 cationic surfactant Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 239000012461 cellulose resin Substances 0.000 description 1
- GVPFVAHMJGGAJG-UHFFFAOYSA-L cobalt dichloride Chemical compound [Cl-].[Cl-].[Co+2] GVPFVAHMJGGAJG-UHFFFAOYSA-L 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007334 copolymerization reaction Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000004031 devitrification Methods 0.000 description 1
- GPLRAVKSCUXZTP-UHFFFAOYSA-N diglycerol Chemical compound OCC(O)COCC(O)CO GPLRAVKSCUXZTP-UHFFFAOYSA-N 0.000 description 1
- USIUVYZYUHIAEV-UHFFFAOYSA-N diphenyl ether Chemical compound C=1C=CC=CC=1OC1=CC=CC=C1 USIUVYZYUHIAEV-UHFFFAOYSA-N 0.000 description 1
- 230000008034 disappearance Effects 0.000 description 1
- POULHZVOKOAJMA-UHFFFAOYSA-M dodecanoate Chemical compound CCCCCCCCCCCC([O-])=O POULHZVOKOAJMA-UHFFFAOYSA-M 0.000 description 1
- YRIUSKIDOIARQF-UHFFFAOYSA-N dodecyl benzenesulfonate Chemical compound CCCCCCCCCCCCOS(=O)(=O)C1=CC=CC=C1 YRIUSKIDOIARQF-UHFFFAOYSA-N 0.000 description 1
- JRBPAEWTRLWTQC-UHFFFAOYSA-N dodecylamine Chemical compound CCCCCCCCCCCCN JRBPAEWTRLWTQC-UHFFFAOYSA-N 0.000 description 1
- 229940071161 dodecylbenzenesulfonate Drugs 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- MEGHWIAOTJPCHQ-UHFFFAOYSA-N ethenyl butanoate Chemical compound CCCC(=O)OC=C MEGHWIAOTJPCHQ-UHFFFAOYSA-N 0.000 description 1
- GFJVXXWOPWLRNU-UHFFFAOYSA-N ethenyl formate Chemical compound C=COC=O GFJVXXWOPWLRNU-UHFFFAOYSA-N 0.000 description 1
- QBDADGJLZNIRFQ-UHFFFAOYSA-N ethenyl octanoate Chemical compound CCCCCCCC(=O)OC=C QBDADGJLZNIRFQ-UHFFFAOYSA-N 0.000 description 1
- BLZSRIYYOIZLJL-UHFFFAOYSA-N ethenyl pentanoate Chemical compound CCCCC(=O)OC=C BLZSRIYYOIZLJL-UHFFFAOYSA-N 0.000 description 1
- UIWXSTHGICQLQT-UHFFFAOYSA-N ethenyl propanoate Chemical compound CCC(=O)OC=C UIWXSTHGICQLQT-UHFFFAOYSA-N 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 230000009477 glass transition Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 229940116335 lauramide Drugs 0.000 description 1
- 229940070765 laurate Drugs 0.000 description 1
- 229940031957 lauric acid diethanolamide Drugs 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000002736 nonionic surfactant Substances 0.000 description 1
- ZPIRTVJRHUMMOI-UHFFFAOYSA-N octoxybenzene Chemical compound CCCCCCCCOC1=CC=CC=C1 ZPIRTVJRHUMMOI-UHFFFAOYSA-N 0.000 description 1
- 125000001117 oleyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])/C([H])=C([H])\C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- AHHWIHXENZJRFG-UHFFFAOYSA-N oxetane Chemical compound C1COC1 AHHWIHXENZJRFG-UHFFFAOYSA-N 0.000 description 1
- 239000005022 packaging material Substances 0.000 description 1
- PNJWIWWMYCMZRO-UHFFFAOYSA-N pent‐4‐en‐2‐one Natural products CC(=O)CC=C PNJWIWWMYCMZRO-UHFFFAOYSA-N 0.000 description 1
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 1
- 229920002492 poly(sulfone) Polymers 0.000 description 1
- 229920006122 polyamide resin Polymers 0.000 description 1
- 229920002312 polyamide-imide Polymers 0.000 description 1
- 229920001230 polyarylate Polymers 0.000 description 1
- 229920001707 polybutylene terephthalate Polymers 0.000 description 1
- 229920005668 polycarbonate resin Polymers 0.000 description 1
- 239000004431 polycarbonate resin Substances 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 229920006393 polyether sulfone Polymers 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 239000009719 polyimide resin Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 230000000379 polymerizing effect Effects 0.000 description 1
- 229920005672 polyolefin resin Polymers 0.000 description 1
- 229920006324 polyoxymethylene Polymers 0.000 description 1
- 229920001955 polyphenylene ether Polymers 0.000 description 1
- 229920002689 polyvinyl acetate Polymers 0.000 description 1
- 239000011118 polyvinyl acetate Substances 0.000 description 1
- 239000004800 polyvinyl chloride Substances 0.000 description 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 1
- 229920001290 polyvinyl ester Polymers 0.000 description 1
- 239000005033 polyvinylidene chloride Substances 0.000 description 1
- OTYBMLCTZGSZBG-UHFFFAOYSA-L potassium sulfate Chemical compound [K+].[K+].[O-]S([O-])(=O)=O OTYBMLCTZGSZBG-UHFFFAOYSA-L 0.000 description 1
- 229910052939 potassium sulfate Inorganic materials 0.000 description 1
- BHZRJJOHZFYXTO-UHFFFAOYSA-L potassium sulfite Chemical compound [K+].[K+].[O-]S([O-])=O BHZRJJOHZFYXTO-UHFFFAOYSA-L 0.000 description 1
- 235000011151 potassium sulphates Nutrition 0.000 description 1
- 235000019252 potassium sulphite Nutrition 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- SCUZVMOVTVSBLE-UHFFFAOYSA-N prop-2-enenitrile;styrene Chemical compound C=CC#N.C=CC1=CC=CC=C1 SCUZVMOVTVSBLE-UHFFFAOYSA-N 0.000 description 1
- POSICDHOUBKJKP-UHFFFAOYSA-N prop-2-enoxybenzene Chemical compound C=CCOC1=CC=CC=C1 POSICDHOUBKJKP-UHFFFAOYSA-N 0.000 description 1
- LYBIZMNPXTXVMV-UHFFFAOYSA-N propan-2-yl prop-2-enoate Chemical compound CC(C)OC(=O)C=C LYBIZMNPXTXVMV-UHFFFAOYSA-N 0.000 description 1
- PNXMTCDJUBJHQJ-UHFFFAOYSA-N propyl prop-2-enoate Chemical compound CCCOC(=O)C=C PNXMTCDJUBJHQJ-UHFFFAOYSA-N 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000005464 sample preparation method Methods 0.000 description 1
- 238000007127 saponification reaction Methods 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 235000010265 sodium sulphite Nutrition 0.000 description 1
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 1
- 235000019345 sodium thiosulphate Nutrition 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- BDHFUVZGWQCTTF-UHFFFAOYSA-M sulfonate Chemical compound [O-]S(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-M 0.000 description 1
- 239000002352 surface water Substances 0.000 description 1
- ILJSQTXMGCGYMG-UHFFFAOYSA-N triacetic acid Chemical compound CC(=O)CC(=O)CC(O)=O ILJSQTXMGCGYMG-UHFFFAOYSA-N 0.000 description 1
- ZIBGPFATKBEMQZ-UHFFFAOYSA-N triethylene glycol Chemical compound OCCOCCOCCO ZIBGPFATKBEMQZ-UHFFFAOYSA-N 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 238000004383 yellowing Methods 0.000 description 1
- 239000011592 zinc chloride Substances 0.000 description 1
- 235000005074 zinc chloride Nutrition 0.000 description 1
- DUNKXUFBGCUVQW-UHFFFAOYSA-J zirconium tetrachloride Chemical compound Cl[Zr](Cl)(Cl)Cl DUNKXUFBGCUVQW-UHFFFAOYSA-J 0.000 description 1
Classifications
-
- 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
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
- G02B1/04—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
-
- 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
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
- Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
- Polarising Elements (AREA)
Abstract
本发明是关于一种聚乙烯醇膜及由其制得的光学膜，该聚乙烯醇膜包含碱化度为95mol％或以上的聚乙烯醇树脂；其中，该聚乙烯醇膜在55℃的4wt％硼酸液中浸泡1分钟所得的面膨润度为17.0％至38.0％，且该聚乙烯醇膜在水中于30℃至55℃区间的储存模量(E’)具有一转折点温度为37至40℃。由本发明的聚乙烯醇膜制成光学膜具有偏光度佳，及偏光度衰退值低的特性。
The present invention relates to a polyvinyl alcohol film and an optical film made from the same, wherein the polyvinyl alcohol film comprises a polyvinyl alcohol resin with a basicity of 95 mol% or more; wherein the polyvinyl alcohol film has a surface swelling degree of 17.0% to 38.0% when immersed in a 4wt% boric acid solution at 55°C for 1 minute, and the storage modulus (E') of the polyvinyl alcohol film in water at a temperature between 30°C and 55°C has a turning point temperature of 37 to 40°C. The optical film made from the polyvinyl alcohol film of the present invention has the characteristics of good polarization and low polarization decay value.
Description
Technical Field
The present invention relates to a polyvinyl alcohol (polyvinyl alcohol, PVA) product, and more particularly, but not exclusively, to a polyvinyl alcohol film and an optical film made therefrom.
Background
Polyvinyl alcohol (polyvinyl alcohol, PVA) film is a hydrophilic material coated and dried from an aqueous solution containing polyvinyl alcohol polymer and plasticizer, and has high transparency, mechanical strength, water solubility, processability, etc., and has been widely used for various optical films of packaging materials or electronic products, for example: a polarizing film.
The polarizing film processed by the polarizing process (manufacturing process) of the polyvinyl alcohol film has the characteristic of allowing only light rays in a specific direction to pass through, and the brightness of the passing light rays can be controlled by the polarizing film; based on this characteristic, the polarizing film is applied to various displays, glasses and wearable devices, and becomes an indispensable component. The so-called polarizing process generally includes swelling, stretching, dyeing, etc.; specifically, the polyvinyl alcohol film is placed in a solution to perform the above steps, dye molecules are diffused between molecules in the polyvinyl alcohol film, and a relatively regular arrangement is obtained by stretching, so that the polarizing film can absorb light components parallel to the arrangement direction thereof, and pass light components in the vertical direction, thereby generating polarization characteristics.
The polarizing film should have suitable optical characteristics such as: high polarization degree and low polarization degree decay value. For this reason, the prior art has changed the structure of polyvinyl alcohol or added functional groups to improve optical characteristics. Prior art such as taiwan patent publication 202231448 provides a polarizing film having excellent polarizing performance and small shrinkage stress, which is to control the total necking rate (a), the necking rate (B) in the stretching step, and the necking rate (C) in the drying step at the same time when manufacturing the polarizing film. By controlling the total necking rate (A), the decrease in the polarizing performance and yield can be suppressed, and by properly controlling the necking rate (B) in the stretching step and the necking rate (C) in the drying step, a polarizing film excellent in the polarizing performance and small in the shrinkage stress can be produced.
In addition, in the prior art, as disclosed in taiwan patent publication 202212872, a dyed triacetylcellulose film is used as a protective layer to suppress the decrease of the polarization degree of the polarizing film under the high-temperature and high-humidity environment.
Disclosure of Invention
In the prior art, when a polyvinyl alcohol film is used for preparing an optical film, the polarization degree is still often seriously declined under long-time use. In this regard, the present inventors have found that by controlling the polyvinyl alcohol film to be immersed in a boric acid solution of a specific concentration, at a specific temperature and for a specific time, the polyvinyl alcohol film has a specific range of surface swelling degree, and a specific range of turning point temperature of storage modulus (E') in a specific temperature range; the prepared polarizing film has excellent polarization degree, and the problem of polarization degree decline of the optical film after long-time use is solved.
Specifically, an aspect of the present invention provides a polyvinyl alcohol film comprising a polyvinyl alcohol resin having an alkalization degree of 95mol% or more; wherein the polyvinyl alcohol film has a surface swelling degree of 17.0% to 38.0% by soaking in a 4wt% boric acid solution at 55 ℃ for 1 minute, and a storage modulus (E') of the polyvinyl alcohol film in water in the range of 30 ℃ to 55 ℃ has a inflection point temperature of 37 to 40 ℃.
In one or more embodiments, the polyvinyl alcohol film has a one-sided swelling of 17.5% to 35.0% and the turning point temperature is 37.8 to 38.5 ℃.
In one or more embodiments, the polyvinyl alcohol film has a TD (Transverse Direction) -direction swell of 9.0% to 18.0% and a MD (Machine Direction) -direction swell of 7.5% to 18.0% when immersed in a 4wt% boric acid solution at 55 ℃ for 1 minute.
In one or more embodiments, the polyvinyl alcohol film has a TD direction swell of 9.0% to 16.50% and the MD direction swell of 8.0% to 16.0%.
In one or more embodiments, the absolute value of the difference between the TD-direction swelling degree and the MD-direction swelling degree of the polyvinyl alcohol film is less than or equal to 5%.
In one or more embodiments, the polyvinyl alcohol film has a ratio of TD-direction swelling degree to MD-direction swelling degree of 0.9 to 1.7.
In one or more embodiments, the polyvinyl alcohol film has a ratio of TD-direction swelling degree to MD-direction swelling degree of 0.95 to 1.60.
In one or more embodiments, the polyvinyl alcohol film has an average degree of polymerization of 1500 to 3500.
In one or more embodiments, the polyvinyl alcohol film has an average degree of polymerization of 2000 to 3500.
In one or more embodiments, the polyvinyl alcohol film has a thickness of 30 to 75 μm.
In another aspect, the present invention provides an optical film made from the polyvinyl alcohol film described above.
In one or more embodiments, the optical film is a polarizing film.
In one or more embodiments, the polarizing film has a degree of polarization of 99.99% or more.
In one or more embodiments, the polarizing film has a polarization degree deterioration value of 0.01% or less after heat treatment at 80 ℃ for 500 hours.
In one or more embodiments, the polarizing film has a surface shrinkage of 2% or less after heat treatment at 80 ℃ for 500 hours.
In one or more embodiments, the polarizing film has a TD shrinkage and an MD shrinkage of 1% or less after heat treatment at 80 ℃ for 500 hours.
The polyvinyl alcohol film of the invention can be suitably used for various applications, particularly for the preparation of optical films, such as: a polarizing film. The polarizing film prepared by using the polyvinyl alcohol film obtained in the technical content of the invention has excellent polarization degree and can improve the fading condition of polarization degree after long-time use.
In addition, the present inventors have found that when the polyvinyl alcohol film of the present invention is immersed in a boric acid solution of a specific concentration, at a specific temperature and for a specific time to have a swelling degree within a specific range, an optical film having improved shrinkage can be produced; further, when the polyvinyl alcohol film has a specific range of TD swelling degree and a specific range of MD swelling degree, the optical film produced therefrom has improved shrinkage in the corresponding directions. Therefore, the invention can avoid the situation that the corner of the optical film is warped due to long-time use under high-heat environment.
Drawings
FIG. 1 is a graph of storage modulus (E') as a function of temperature in water for a polyvinyl alcohol film according to an embodiment of the invention;
fig. 2 to 4 are schematic views of a sample preparation method of a polyvinyl alcohol film according to an embodiment of the invention in analyzing the temperature of its turning point.
Detailed Description
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to embodiments of the invention and specific examples, but will be used to describe the same. In this specification and the claims that follow, except where the context requires otherwise, the word "a" or "an" will be understood to mean a plurality.
Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. However, any numerical value inherently contains certain standard deviations found in their respective testing measurements. As used herein, the term "about" means that the actual value falls within the acceptable standard deviation of the average value, as determined by one of ordinary skill in the art to which the present invention pertains.
[ Polyvinyl alcohol film ]
In one aspect, the present invention provides a polyvinyl alcohol film comprising a polyvinyl alcohol resin having an alkalization degree of 95mol% or more; wherein the polyvinyl alcohol film has a surface swelling degree of 17.0% to 38.0% by soaking in a 4wt% boric acid solution at 55 ℃ for 1 minute, and a storage modulus (E') of the polyvinyl alcohol film in water in the range of 30 ℃ to 55 ℃ has a inflection point temperature of 37 to 40 ℃. According to some embodiments, the polyvinyl alcohol film of the invention has a thickness of 30 to 75 μm. Specifically, ranges of any two of the following values, for example: 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, the foregoing values being illustrative only and not limiting.
The "swelling degree" as referred to herein includes "surface swelling", "TD (TRANSVERSE DIRECTION) swelling degree (hereinafter referred to as TD swelling degree)" and "MD (Machine Direction) swelling degree (hereinafter referred to as MD swelling degree)" of the polyvinyl alcohol film. The term "surface swelling degree (hereinafter referred to as surface swelling degree) obtained by immersing the polyvinyl alcohol film in a 4wt% boric acid solution at 55℃for 1 minute" as used herein is obtained by immersing the polyvinyl alcohol film in a 4wt% boric acid solution at 55℃for 1 minute and then calculating the area change amount of the polyvinyl alcohol film.
The polyvinyl alcohol film has crystalline regions and amorphous regions. When the polyvinyl alcohol film is soaked in boric acid liquid, the aqueous solution containing boric acid enters an amorphous area in the film, and part of crystals are dissolved; boric acid in solution will also further crosslink with molecules. The present inventors have found that the numerical range of the surface swelling degree is related to the polarization degree, the polarization degree deterioration condition, and the shrinkage ratio of the optical film to be subsequently produced. It is presumed that the more the polycrystal dissolves, the more the number of boric acid bonds becomes, and the more stable the intermolecular structure becomes. The possible reason is that after the crystallization part is dissolved, the chain segments at the dissolved position are relatively orderly arranged, can freely move and change the interval between the chain segments, and can generate more positions suitable for boric acid bonding; the amorphous segments themselves have a small number of sites capable of bonding to boric acid due to their irregular spacing and random arrangement. Thus, when the swelling degree of the polyvinyl alcohol film is too low, it means that the dissolved crystals are less, and the number of segments and regions capable of being crosslinked with boric acid are also less, so that the intermolecular structure is relatively unstable, the intermolecular structure is susceptible to heat change, and further the subsequent optical film is degraded in polarization degree, and surface shrinkage is easily generated to deform the polarizing film. On the other hand, when the swelling degree is too high, it means that too many crystals are dissolved in the polyvinyl alcohol film, but the amount of crystals in the polyvinyl alcohol film is insufficient, and the physical strength of the film is lowered to be easily broken.
Therefore, in order to make the polyvinyl alcohol film have stable intermolecular structure and good physical strength, the surface swelling degree needs to be controlled in a specific range; specifically, the polyvinyl alcohol film of the invention has a surface swelling degree of 17.0% to 38.0% as obtained by immersing in a 4wt% boric acid solution at 55 ℃ for 1 minute, such as in the range of any two of the following values, for example ：17.0％、17.5％、18.0％、18.5％、19.0％、19.5％、20.0％、20.5％、21.0％、21.5％、22.0％、22.5％、23.0％、23.5％、24.％0、24.5％、25.0％、25.5％、26.0％、26.5％、27.0％、27.5％、28.0％、28.5％、29.0％、29.5％、30.0％、30.5％、31.0％、31.5％、32.0％、32.5％、33.0％、33.5％、34.0％、34.5％、35.0％、35.5％、36.0％、36.5％、37.0％、37.5％、 or 38.0%; preferably, the polyvinyl alcohol film has a surface swelling degree of 17.5 to 35.0% or 35%.
The modulus is a physical property characteristic used for analyzing the relation between stress and strain in the material mechanics and is the ratio of the stress to the strain; if the stress applied to the material is a positive force, the modulus obtained is denoted as E; the "storage modulus (E')" is the storage energy converted by the material absorbing and applying energy, and is generally used for restoring deformation and maintaining the original appearance of the material, and is related to the elastic characteristics of the material; it can also reflect the rigidity of the material, from a molecular point of view, a higher storage modulus (E') indicating a stronger intermolecular force.
The "storage modulus (E ') having a transition point temperature (hereinafter referred to simply as E ' transition point temperature) in water in the range of 30℃to 55℃as described herein is obtained by immersing a polyvinyl alcohol film in water and measuring the change in storage modulus (E ') of the polyvinyl alcohol film in a temperature-rising mode. After a large amount of moisture is absorbed by the film, molecular chains of the polyvinyl alcohol are swelled and separated, so that the inter-molecular-chain entanglement is reduced, and the response of the storage modulus (E') is more influenced by crystallization in the film; thus, storage modulus (E') analysis in polyvinyl alcohol bubble water can be used to evaluate the change in crystallinity in films at different temperatures. Further, the change curve of the storage modulus (E ') of the polyvinyl alcohol film in water with temperature has the characteristics as shown in FIG. 1, the change curve between 30 ℃ and 55 ℃ has two different slopes, and the tangential intersection point of the two slopes is the E ' turning point, and the corresponding temperature is the E ' turning point temperature (as indicated by the arrow in FIG. 1).
The inventors found that the physical meaning represented by the E' turning point temperature includes that it is the temperature at which crystallization within the polyvinyl alcohol film begins to dissolve in large amounts; if the temperature of the E' turning point is higher, the average crystal particles in the film are larger, so that a large amount of crystals are dissolved at a relatively high temperature. Without being limited by a particular theory, it is speculated that when the crystal grain size is controlled within a suitable range, the polyvinyl alcohol film will have the number and area of crystal residues most suitable for crosslinking with boric acid, such that the optical film (e.g., polarizing film) made from the polyvinyl alcohol film has the effect of less deterioration of the polarization degree under high temperature and long-term use.
Therefore, in order to obtain the above effects, the temperature of the E' turning point needs to be controlled within a specific range; specifically, the polyvinyl alcohol film of the present invention has a storage modulus (E') in water in the range of 30 ℃ to 55 ℃ (temperature range of first stretching in the polarizing film process) with a transition point temperature of 37 to 40 ℃, such as, but not limited to ：37℃、37.1℃、37.3℃、37.5℃、37.7℃、37.9℃、38℃、38.1℃、38.3℃、38.5℃、38.7℃、38.9℃、39℃、39.1℃、39.3℃、39.5℃、39.7℃、39.9℃ or 40 ℃; preferably, the E' turning point temperature of the polyvinyl alcohol film is in the range of 37.8 to 38.5 ℃, such as any two of the following values, for example: 37.8 ℃, 37.9 ℃, 38.0 ℃, 38.1 ℃, 38.2 ℃, 38.3 ℃, 38.4 ℃ or 38.5 ℃. It should be noted that when the equivalent temperature is higher than 55 ℃, the physical properties of the polyvinyl alcohol film may change rapidly due to complete disappearance of the crystals, so that the analysis temperature interval should be set to avoid exceeding 55 ℃ when analyzing the turning point temperature.
In addition, regarding the above-mentioned measurement method of the temperature of the E 'turning point, since the polyethylene film absorbs water (even moisture in the air) to affect the state of its crystalline state, the moisture content of each polyethylene film to be measured may be adjusted to be uniform by pretreatment before the temperature of the E' turning point is measured by the polyethylene film, so that the state of each polyethylene film to be measured is uniform. The water content may be generally adjusted to about 8wt% to 9wt%, but is not limited thereto herein.
As used herein, "degree of basicity" is a measured value obtained according to JIS K6726 (1994) standard test method. In one or more embodiments, the polyvinyl alcohol resin has an alkalization degree of 95mol% or more, for example: 95mol% or more, 95.5mol% or more, 96mol% or more, 96.5mol% or more, 97mol% or more, 97.5 mol% or more, 98mol% or more, 98.5mol% or more, 99mol% or more, or 99.5mol% or more. According to an embodiment of the present invention, the polyvinyl alcohol-based resin of the present invention has an alkalization degree of more than 99.90mol%, such as more than 99.90mol%, more than 99.92mol%, more than 99.94mol%, more than 99.96mol%, or more than 99.98mol%; preferably, the polyvinyl alcohol resin has an alkalization degree of 99.95mol% or more, for example: 99.95mol% or more, 99.97mol% or more, or 99.99mol% or more; more preferably, the polyvinyl alcohol resin has an alkalization degree of 99.97mol% or more, for example: 99.97mol% or more, 99.98mol% or more, or 99.99mol% or more.
The term "TD-direction swelling degree (hereinafter abbreviated as TD-direction swelling degree) obtained by immersing the polyvinyl alcohol film in the 4wt% boric acid solution 1 at 55 ℃ for 1 minute" as used herein means that the change in length of the polyvinyl alcohol film in the TD direction and in the MD direction is calculated after immersing the polyvinyl alcohol film in the 4wt% boric acid solution at 55 ℃ for 1 minute. Wherein the TD direction is also referred to as the transverse direction and the MD direction is also referred to as the mechanical direction. Without being limited by a specific theory, when the TD swelling degree and the MD swelling degree of the polyvinyl alcohol film are respectively controlled in a specific range, the TD shrinkage rate and the MD shrinkage rate of the optical film manufactured subsequently can be respectively reduced, so that the optical film attached to the display device can avoid corner warpage of the optical film under high temperature and long-time use.
Therefore, in order to obtain the above-described effects, the polyvinyl alcohol film of the invention has a TD-direction swelling degree of 9.0% to 18.0%, such as in the range of any two of the following values, for example ：9.0％、9.5％、10.0％、10.5％、11.0％、11.5％、12.0％、12.5％、13.0％、13.5％、14.0％、14.5％、15.0％、15.5％、16.0％、16.5％、17.0、17.5％ or 18.0%; more preferably, the polyvinyl alcohol film has a TD-direction swelling degree of 9.0% to 16.5%; and, the polyvinyl alcohol film has an MD direction swelling degree in the range of 7.5% to 16.0%, such as any two of the following values, for example: 7.5%, 8.0%, 8.5%, 9.0%, 9.5%, 10.0%, 10.5%, 11.0%, 11.5%, 12.0%, 12.5%, 13.0%, 13.5%, 14.0%, 14.5%, 15.0%, 15.5% or 16.0%; more preferably, the polyvinyl alcohol film has an MD-direction swelling degree of 8.0% to 16.0%.
In one or more embodiments, the absolute value of the difference between the TD-direction swelling degree and the MD-direction swelling degree of the polyvinyl alcohol film is less than or equal to 5%, for example: less than or equal to 5%, less than or equal to 4.5%, less than or equal to 4%, less than or equal to 3.5%, less than or equal to 3%, less than or equal to 2.5%, less than or equal to 2%, less than or equal to 1.5%, less than or equal to 1% or less than or equal to 0.5%.
In one or more embodiments, the polyvinyl alcohol film has a ratio of TD-direction swelling degree to MD-direction swelling degree of 0.95 to 1.60, such as in the range of any two of the following values, for example: 0.95, 1.00, 1.05, 1.10, 1.15, 1.20, 1.25, 1.30, 1.35, 1.40, 1.45, 1.50, 1.55, or 1.60.
Without being limited by a specific theory, when the absolute value or the ratio of the difference between the TD-direction swelling degree and the MD-direction swelling degree is too large, a subsequently manufactured display including the polyvinyl alcohol film may have a phenomenon that the polarizing film is peeled off from the protective layer or the polarizing film is peeled off from the glass, thereby causing a problem of deterioration of the display.
As used herein, the "average polymerization degree" is measured according to JIS K6726 (1994) standard test method. In one or more embodiments, the polyvinyl alcohol film has an average degree of polymerization in the range of 1500 to 3500, such as any two of the following values, e.g., ：1500、1600、1700、1800、1900、2000、2100、2200、2300、2400、2500、2600、2700、2800、2900、3000、3100、3200、3300、3400 or 3500; preferably, the polyvinyl alcohol film has an average polymerization degree of 2000 to 3500.
Without being limited by a particular theory, the inventors have found that the above-mentioned degree of surface swelling, temperature of the E' turning point, degree of TD-direction swelling, and degree of MD-direction swelling can be controlled by adjusting the average polymerization degree of the resin raw material of the polyvinyl alcohol film; in addition, the dissolution temperature and time of the raw materials in the production method, the total drying time at more than 50 ℃ and the molecular alignment of the polyvinyl alcohol polymer in the polyvinyl alcohol film can be controlled, but the method is not limited thereto.
[ Method for producing polyvinyl alcohol film ]
The method for producing a polyvinyl alcohol film of the present invention generally comprises the steps of: (a) dissolution process: heating and dissolving a polyvinyl alcohol resin, and adjusting the concentration of the polyvinyl alcohol resin to form a polyvinyl alcohol casting solution; (b) a casting process: casting the polyvinyl alcohol casting solution to a casting drum, and stripping from the casting drum to obtain a polyvinyl alcohol primary forming film; (c) a hot roll process: contacting the polyvinyl alcohol primary formed film with a plurality of hot rolls to obtain a polyvinyl alcohol film semi-finished product; (d) an oven process: drying the semi-finished product of the polyvinyl alcohol film in an oven to obtain a finished product of the polyvinyl alcohol film; and (e) temperature and humidity adjusting process: placing the polyvinyl alcohol film finished product into a temperature and humidity regulating box, and regulating the temperature and the humidity to obtain a polyvinyl alcohol film; wherein, in the hot roller and oven process, the total drying time at the temperature of more than 50 ℃ is controlled to be 10 to 20 minutes.
[ Dissolution Process ]
According to some embodiments, the dissolution process mainly comprises stirring the polyvinyl alcohol resin, solvent, plasticizer, etc. to raise the temperature to 130-165 ℃, and dissolving for 1-5 hours, and adjusting the resin to a proper concentration, thereby obtaining the polyvinyl alcohol casting solution. Suitable concentrations of the resin are about 20wt% to 50wt%, for example: 20wt%, 30wt%, 40wt% or 50wt%; if the resin concentration is too low, the drying load of the subsequent film becomes high; conversely, if the resin concentration is too high, the viscosity is too high, which makes film formation difficult.
In one or more embodiments, the polyvinyl alcohol resin used in the dissolution process is prepared by polymerizing a vinyl ester resin monomer to form a polyvinyl ester resin having an average polymerization degree of 1500 to 3500, and then performing a saponification reaction to obtain a polyvinyl alcohol resin having an alkalization degree of more than 95 mol%. It is believed that the average degree of polymerization can affect the dissolution and stretching of polyvinyl alcohol molecules in water, thereby affecting the crystalline particles and crystallinity of the finished polyvinyl alcohol film. The larger the degree of polymerization, the larger the crystalline particles and the higher the degree of crystallinity of the finished polyvinyl alcohol film; however, too high a degree of polymerization would result in too large crystalline particles, which in turn would affect the E' turning point temperature; in addition, too low a polymerization degree may result in too low an E' turning point and also in too low a mechanical strength of the film.
The vinyl ester resin monomer may be vinyl esters such as vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, or vinyl caprylate, or combinations thereof, and is not limited in the present invention. Preferably, vinyl acetate is used. The vinyl ester resin monomer may be modified by copolymerization with an olefin compound or an acrylate derivative. Wherein the olefin compound may be ethylene, propylene, butylene, etc., and is not limited in the present invention; the amount of the olefin compound added may be, but is not limited to, 2mol% to 4mol%, for example, 2mol%, 2.5mol%, 3mol%, 3.5mol%, 4mol%, or the like. The acrylate derivative may be acrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, or the like, and is not limited in the present invention.
In one or more embodiments, the solvent used in the dissolution process is not limited to one that can dissolve the polyvinyl alcohol resin. As solvents, for example, but not limited to: water, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, ethylenediamine, diethylenetriamine and the like may be used singly or in combination. In the present invention, water is preferable as a solvent in view of environmental and economical aspects.
In one or more embodiments, the "plasticizer" as described herein may be specifically, but is not limited to: glycerol, ethylene glycol, propylene glycol, diethylene glycol, diglycerol, triethylene glycol, tetraethylene glycol, trimethylolpropane, or the like, or combinations of any of the foregoing plasticizers; in the present invention, glycerin is preferred. And in one or more embodiments, the plasticizer is added in an amount of 5wt% to 15wt% relative to the weight of the polyvinyl alcohol resin, such as, but not limited to, specifically 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt% and 15wt%, and in a preferred embodiment, the plasticizer is added in an amount of 10wt% relative to the weight of the polyvinyl alcohol resin.
In addition to the plasticizer, other additives may be optionally added in the dissolution process, including but not limited to surfactants (surfactants); the surfactant may include, but is not limited to, cationic, anionic or nonionic surfactants, and may specifically be, but is not limited to: carboxylate type such as potassium laurate, sulfate type such as sodium laureth sulfate, sulfonate type such as dodecylbenzene sulfonate, alkylphenyl ether type such as polyethylene oxide octylphenyl ether, alcohol-based phenyl ether type such as polyethylene glycol monooctylphenyl ether, alkyl ester type such as polyethylene oxide laurate, alkylamine type such as polyethylene oxide laurylamine ether, alkylamide type such as polyethylene oxide lauramide, polypropylene glycol ether type such as polyethylene oxide polyoxypropylene ether, alkanolamide type such as lauric acid diethanolamide and oleyl diethanolamide, allyl phenyl ether type such as polyallylphenyl ether, sodium laureth sulfate, and the like.
In one or more embodiments, the temperature at which the aqueous solution of the polyvinyl alcohol resin is dissolved is preferably in the range of 130 to 165 ℃, such as any two of the following values, specifically for example: 130 ℃, 135 ℃, 140 ℃, 145 ℃, 150 ℃, 155 ℃, 160 ℃, or 165 ℃. It is believed that this dissolution temperature affects the dissolution of the polyvinyl alcohol resin and the dispersion of the additives. When the dissolution temperature is higher, the dissolution effect of the polyvinyl alcohol resin and the dispersion effect of the additive are better, so that the formed polyvinyl alcohol film has smaller crystal particles and lower crystallinity; however, when the dissolution temperature is too high, localized yellowing of the polyvinyl alcohol film formed may be caused. On the contrary, without being limited by a specific theory, when the dissolution temperature is too low, the dissolution effect of the polyvinyl alcohol resin and the dispersion effect of the additive are poor, and the formed crystal particles of the polyvinyl alcohol film are larger, so that the E' turning point temperature of the polyvinyl alcohol film is too high.
In one or more embodiments, the time for dissolving the aqueous solution of the polyvinyl alcohol resin is preferably 1 to 5 hours, such as in the range of any two of the following values, specifically for example: 1 hour, 2 hours, 3 hours, 4 hours or 5 hours. It is believed that this dissolution time affects the dissolution of the polyvinyl alcohol resin and the dispersion of the additives. The longer the dissolution time, the better the dissolution of the polyvinyl alcohol resin and the dispersion effect of the additive, and further the smaller the crystalline particles of the polyvinyl alcohol film, the lower the crystallinity. On the contrary, without being limited by a specific theory, when the dissolution time is too short, the dissolution of the polyvinyl alcohol resin and the dispersion effect of the additive are poor, and the formed crystal particles of the polyvinyl alcohol film are larger, so that the E' turning point temperature of the polyvinyl alcohol film is too high.
[ Casting Process ]
According to some embodiments, the polyvinyl alcohol casting solution is mainly delivered to a double screw extruder, and is mixed uniformly and defoamed again by the extruder (for example, but not limited to, defoamed by the double screw extruder), and then is ejected from a T-shaped slit die lip, and is cast onto a rotating high-temperature casting drum (or casting drum), an endless belt, etc. as a support to form a film, thereby obtaining a polyvinyl alcohol primary formed film. In one or more embodiments, the delivery temperature of the polyvinyl alcohol casting solution during delivery during the casting process is preferably controlled to be at least 90 ℃ or more, such as, but not limited to: 90 ℃, 91 ℃, 92 ℃, 93 ℃, 94 ℃,95 ℃, 96 ℃, 97 ℃, 98 ℃ or 99 ℃; in addition, the polyvinyl alcohol casting solution after being again uniformly mixed and defoamed by the extruder must be controlled to be at least 90 ℃ or more, for example but not limited to: 90 ℃, 91 ℃, 92 ℃, 93 ℃, 94 ℃,95 ℃, 96 ℃, 97 ℃ or 98 ℃.
In one or more embodiments, when the polyvinyl alcohol casting solution is cast onto a rotating high temperature casting drum, the temperature of the casting drum is preferably 85 to 95 ℃, and the time the polyvinyl alcohol is retained on the casting drum is preferably 0.6 to 1.2 minutes.
[ Hot roll Process ]
According to some embodiments, the hot roll process is mainly to dry the polyvinyl alcohol film after being peeled from the casting drum through a plurality of hot rolls on the upper and lower surfaces, and then further obtain a semi-finished product of the polyvinyl alcohol film. Wherein the temperature of the plurality of heat rolls (e.g., 13 to 19 heat rolls) is gradually decreased from high to low, and the initial heat roll is the highest Wen Zhe (e.g., but not limited to 90 to 99 ℃, and may be, for example, but not limited to 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99 ℃) among all heat rolls, and the final heat roll is the lowest (e.g., but not limited to 25 to 40 ℃, and may be, for example, but not limited to 25, 30, 35, or 40 ℃) among all heat rolls.
[ Oven Process ]
According to some embodiments, the oven process mainly uses an oven to dry the upper and lower surfaces of the semi-finished product of the polyvinyl alcohol film peeled off from the hot roller (for example, but not limited to, drying with hot air and infrared light), so as to obtain a finished product of the polyvinyl alcohol film. In one or more embodiments, the oven is preferably a floating oven, and the temperature is controlled between 100 and 120 ℃, for example: 100 ℃, 105 ℃, 110 ℃, 115 ℃ or 120 ℃; preferably 110 ℃.
In one or more embodiments, in the hot roll process and the oven process, the total drying time at a temperature of more than 50 ℃ is 10 to 20 minutes, specifically, for example: 10 minutes, 15 minutes or 20 minutes. It is believed that the total drying time at greater than 50 ℃ affects the surface swelling degree, TD-direction swelling degree, MD-direction swelling degree, and E' -turning point temperature of the polyvinyl alcohol film. Without being bound by a particular theory, it is speculated that the polymer chains are free to move in a small range at drying temperatures greater than 50 ℃ because the glass transition temperature of the polyvinyl alcohol film product at a water content of 2wt% is 40 to 50 ℃. Therefore, when the total drying time is longer, the crystal grains are larger and the crystallinity is higher; on the contrary, as the total drying time is shorter, the crystal particles are smaller, and the crystallinity is lower, thereby affecting the swelling degree and the E' turning point temperature of the polyvinyl alcohol film.
[ Temperature and humidity control Process ]
According to one embodiment of the present disclosure, the finished polyvinyl alcohol film can be placed in a temperature and humidity adjusting box for temperature and humidity adjustment after the above process is completed.
In one or more embodiments, the temperature of the temperature and humidity chamber is between 35 and 45 ℃, specifically in a range between any two of the following values, for example: 35 ℃, 40 ℃ or 45 ℃, preferably e.g. 45 ℃. In one or more embodiments, the relative humidity of the conditioning box is preferably, for example, between 40% and 60%, such as in the range between any two of the following values, for example: 40%, 45%, 50%, 55% or 60%, preferably for example 50%. In one or more embodiments, the polyvinyl alcohol film is allowed to stand in the temperature and humidity conditioning tank for a period of time preferably, for example, 20 to 40 minutes, for example: 20 minutes, 25 minutes, 30 minutes, 35 minutes or 40 minutes. In one or more embodiments, the polyvinyl alcohol film is placed in a temperature and humidity conditioning cabinet at 45 ℃ and 50% relative humidity for 30 minutes, for example.
In addition, according to an embodiment of the present disclosure, in the oven process, the two sides of the film may be further clamped by a clamp, and a tensile force in the TD direction is additionally applied to maintain the dimension of the film in the TD direction, so as to adjust the molecular alignment of the film. Because the polyvinyl alcohol film is stretched in the MD direction, the polyvinyl alcohol polymer is easy to align along the MD direction; therefore, after the force is applied to the film in the TD direction, the alignment of the polyvinyl alcohol polymer can be balanced, and the difference of swelling degree in the two directions can be reduced.
[ Optical film ]
Another object of the present invention is to provide an optical film made from the polyvinyl alcohol film described above. The "optical film" described herein may be a polarizing film, a retardation film, a viewing angle improving film, a brightness improving film, or the like, particularly a polarizing film.
As used herein, "degree of polarization" is measured according to the standard method of JIS Z8722. In one or more embodiments, the polarizing film of the present invention has a degree of polarization of 99.99% or more; specific examples are: 99.990% or more, 99.992% or more, 99.994% or more, 99.996% or more, and 99.998% or more.
In one or more embodiments, the polarizing film has a polarization degree degradation value of 0.01% or less after heat treatment at 80 ℃ for 500 hours; specifically, for example, 0.010% or less, 0.009% or less, 0.008% or less, 0.007% or less, 0.006% or less, or 0.005% or less.
In one or more embodiments, the polarizing film has a surface shrinkage of 2% or less after heat treatment at 80 ℃ for 500 hours; specifically, for example, 2% or less, 1.9% or less, 1.8% or less, 1.7% or less, 1.6% or less, 1.5% or less, and 1.4% or less.
In one or more embodiments, the polarizing film has a TD shrinkage and an MD shrinkage of 1% or less after heat treatment at 80 ℃ for 500 hours; specifically, for example, all less than or equal to 1%, all less than or equal to 0.95%, all less than or equal to 0.90%, all less than or equal to 0.85%, all less than or equal to 0.80%, and all less than or equal to 0.75%.
[ Method for producing optical film ]
According to some embodiments, the "method of manufacturing an optical film" described herein refers to a method of manufacturing a polarizing film, and further, a polyvinyl alcohol film is manufactured as a polarizing film. The method for producing the polarizing film comprises a dyeing step of adsorbing iodine ions, a boric acid treatment step and a water washing step; the stretching step of uniaxial stretching may be performed at the boric acid treatment step or at a stage prior thereto. Preferably, a swelling step of swelling the polyvinyl alcohol film with water may be provided before the dyeing step. In addition to this, a final drying step is usually provided after the water washing step.
In the swelling step, the polyvinyl alcohol film is immersed in a treatment bath (e.g., pure water) at a temperature of 30 to 55℃to carry out the film surface washing and swelling treatment for a period of usually 5 to 300 seconds, preferably 20 to 240 seconds. According to some embodiments, a plurality of guide rollers are disposed in a swelling tank accommodating a treatment bath to convey the polyvinyl alcohol film. Subsequently, the polyvinyl alcohol film is stretched to 1.05 to 2.5 times the original length in the MD direction, and then subjected to a dyeing step.
In the dyeing step, the polyvinyl alcohol film after the swelling step is immersed in a dyeing tank containing a dyeing bath. The dyeing conditions may be determined in such a manner that iodine is adsorbed to the polyvinyl alcohol film without causing any adverse effects such as extreme dissolution and devitrification of the film. The dyeing bath in the dyeing step is, for example, an aqueous solution containing iodine and potassium iodide, the concentration of iodine in the dyeing bath is preferably 0.01 to 0.5wt%, and the concentration of potassium iodide is preferably 0.01 to 10wt%; specific examples may be, but are not limited to, aqueous solutions of iodine at a concentration of 0.037wt% with potassium iodide at a concentration of 1.85 wt%. In addition, other iodides such as zinc iodide may be used instead of potassium iodide, or in addition to potassium iodide, other iodides may be used in combination. The temperature of the dyeing bath is usually 20 to 40 ℃, for example 20 ℃, 30 ℃ or 40 ℃, and the time of the dyeing treatment (dyeing time) is usually 10 to 600 seconds, preferably 30 to 200 seconds. Then, stretching the polyvinyl alcohol film to 2 to 4 times of the original length along the mechanical direction, and then carrying out boric acid treatment and stretching steps.
In the boric acid treatment and stretching step, the iodine-dyed polyvinyl alcohol film is treated with an aqueous solution containing boric acid to crosslink it, and the adsorbed iodine is immobilized in the resin. This step is usually carried out by immersing the polyvinyl alcohol film after the dyeing step in a fixing tank containing a treatment bath containing boric acid. The boric acid treatment bath preferably contains iodide in addition to boric acid, and the iodide used may be potassium iodide or zinc iodide, etc., for example, an aqueous solution containing boric acid and potassium iodide each at a concentration of 5.5 wt%. In addition, compounds other than iodide may be allowed to coexist in the boric acid treatment bath, for example: zinc chloride, cobalt chloride, zirconium chloride, sodium thiosulfate, potassium sulfite, sodium sulfite, potassium sulfate, sodium sulfate, and the like. The boric acid treatment and extension steps are generally carried out at 50 to 70 ℃, preferably for example at 55 ℃; the treatment time is usually 10 to 600 seconds, preferably 20 to 300 seconds, more preferably 20 to 100 seconds. Then stretching the polyvinyl alcohol film to more than 3 times of the original length along the mechanical direction, and then carrying out the subsequent steps; the upper limit of the stretching ratio is not particularly limited, but is preferably 8 times or less, for example, to include, but not limited to, 3.3 times or more, such as 3.3 to 8.0 times, more preferably 3.5 to 6.0 times, particularly preferably 4.0 to 5.5 times.
The polyvinyl alcohol film is subjected to the steps and the subsequent water washing and drying steps to form a polarizing film. In the water washing and drying step, the iodine solution and boric acid remaining on the membrane surface are washed with water or an aqueous solution containing iodide, for example, but not limited to, water washing with an aqueous potassium iodide solution having a concentration of 5.5 wt%. Then, a drying step, such as but not limited to drying for 5 minutes using an oven at 60 ℃, is performed to form a polarizing film. Further, a protective layer may be formed on at least one side of the polarizing film to form a polarizing film product (or referred to as a polarizer). In detail, the protective layer is preferably a member having a function of preventing abrasion of the surface of the polarizing film, and the like, and includes a transparent resin. According to various embodiments, the protective layer may be disposed on only one side of the polarizing film, but is preferably formed on both sides of the polarizing film. The protective layer may be a protective film of a transparent resin material; the transparent resin may be an acrylic resin such as a methyl methacrylate resin, an olefin resin, a polyvinyl chloride resin, a cellulose resin, a styrene resin, an acrylonitrile-butadiene-styrene copolymer resin, an acrylonitrile-styrene copolymer resin, a polyvinyl acetate resin, a polyvinylidene chloride resin, a polyamide resin, a polyacetal resin, a polycarbonate resin, a modified polyphenylene ether resin, a polyester resin (such as a polybutylene terephthalate resin and a polyethylene terephthalate resin), a polysulfone resin, a polyethersulfone resin, a polyarylate resin, a polyamideimide resin, a polyimide resin, an epoxy resin, an oxetane resin, or the like; preferably, a cellulose-based resin is used, for example: cellulose Triacetate (TAC).
Examples
Hereinafter, the present invention will be described in further detail with reference to specific examples. However, it should be understood that these specific examples are only for the purpose of helping to make the invention more easily understandable and are not intended to limit the scope of the invention.
1. Preparation of polyvinyl alcohol film
Here, the present invention provides a non-limiting method of preparing a polyvinyl alcohol film. Non-limiting example polyvinyl alcohol films (examples 1 to 12) and comparative example polyvinyl alcohol films (comparative examples 1 to 5) were prepared according to methods similar to those disclosed below.
The following are the main steps common to the manufacture of the polyvinyl alcohol films of the present example and comparative example, and table 1 below will present the differences in one or more process parameters of the present example and comparative example in detail:
[ dissolution Process ]: adding 1800 kg of polyvinyl alcohol resin with average polymerization degree of 1500-3500 (shown in table 1) and alkalization degree of 99.95mol%, 4000 kg of water and 180 kg of plasticizer glycerol into a dissolution barrel, respectively raising dissolution temperature to 130-165 ℃ while stirring (shown in table 1), and respectively controlling dissolution time to 1-5 hours (shown in table 1); after the solution is uniformly dissolved, adding water to adjust the concentration of the resin to 30 weight percent, and obtaining the polyvinyl alcohol casting solution. Among these, the polyvinyl alcohol resins used in examples and comparative examples were polyvinyl alcohol resins polymerized from vinyl acetate and unmodified (i.e., without other comonomers); the specific average polymerization degree, dissolution temperature and dissolution time of the polyvinyl alcohol resin are shown in table 1.
[ Casting Process ]: and (3) conveying the polyvinyl alcohol casting solution to a double-screw extruder, uniformly mixing and defoaming by the extruder again, controlling the temperature of the casting solution to 98 ℃, then spitting the casting solution out of a T-shaped slit die lip, and casting to a rotating high-temperature casting drum for drying and film making to form a primary formed film.
[ Hot roll Process ]: after the polyvinyl alcohol primary forming film is peeled off from the casting drum, 13 hot rolls are used for contacting the upper surface and the lower surface of the drying film, and the 1 st hot roll is the highest Wen Zhe in all hot rolls and is 95 ℃; and the temperature of the continuous hot roller gradually decreases from high to low until the 13 th hot roller temperature decreases to 30 ℃.
[ Oven Process ]: drying by using a floating oven, and drying by hot air and infrared light on the upper and lower surfaces of the film to obtain a polyvinyl alcohol film finished product. In a different example, the floating type oven is used for drying, and the floating type oven is further used for clamping two sides of the film by a clamp, so that the dimension of the film in the TD direction is maintained by applying the tensile force in the TD direction.
Wherein, in the casting, hot roll and oven processes described above, the total time of drying at a temperature of greater than 50 ℃ was controlled (specific duration is shown in table 1).
[ Temperature and humidity control Process ]: and then placing the finished polyvinyl alcohol film product into a temperature and humidity regulating box with the temperature of 45 ℃ and the relative humidity of 50 percent for 30 minutes to obtain the polyvinyl alcohol film.
TABLE 1
2. Polarizing film preparation
Here, the present invention provides a non-limiting method of preparing an optical film from a polyvinyl alcohol film, and in particular, a non-limiting method of preparing a polarizing film. According to the methods disclosed below, non-limiting example polyvinyl alcohol films (examples 1 to 12) and comparative example polyvinyl alcohol films (comparative examples 1 to 5) were prepared as corresponding polarizing films.
The following are the main steps shared by the preparation of polarizing films according to examples and comparative examples of the present invention: unreeling the polyvinyl alcohol film, and then putting the polyvinyl alcohol film into a swelling tank filled with pure water at 30 ℃ to carry out film surface water washing and swelling treatment; stretching the polyvinyl alcohol film to 1.2 times of the original length along the mechanical direction, then putting the polyvinyl alcohol film into a dyeing tank containing an aqueous solution of iodine with the concentration of 0.037wt% and potassium iodide with the concentration of 1.85wt% at the temperature of 30 ℃ for dyeing, and simultaneously stretching the polyvinyl alcohol film to 3.4 times of the original length along the mechanical direction; after dyeing, the polyvinyl alcohol film enters an extension tank which is controlled at 55 ℃ and contains 5.5wt% concentration aqueous solution of boric acid and potassium iodide, and after the polyvinyl alcohol film is extended to 6 times of the original length along the mechanical direction, the iodine solution and boric acid remained on the film surface are cleaned by the 5.5wt% aqueous solution containing potassium iodide. And then drying for 5 minutes by a 60 ℃ oven, and adhering and drying the upper surface and the lower surface by using a cellulose triacetate protective film to prepare the polarizing film.
3. Analysis method
The present invention provides methods for analyzing and testing the polyvinyl alcohol films of examples 1 to 12 and comparative examples 1 to 5.
Degree of basification
The method for measuring the basicity of the present invention is a method according to JIS K6726 (1994) standard.
Average degree of polymerization
The method for measuring the polymerization degree of the present invention is a method according to JIS K6726 (1994).
Degree of swelling
1. Test conditions: cutting a polyvinyl alcohol film into square samples z with the MD direction of 10 cm and the TD direction of 10 cm, clamping the edges of the samples with a long tail clamp and glass, and soaking the samples in boric acid solution with the temperature of 55 ℃ and the concentration of 4wt% for 1 minute to swell the samples; and after swelling is finished, taking out the sample and the glass, removing the long tail clamp, spreading the swelled sample, and measuring the length of the swelled sample in the MD direction and the length of the swelled sample in the TD direction respectively by using a vernier scale.
2. Calculation formula of swelling degree in each direction (MD direction and TD direction):
3. The calculation formula of the surface swelling degree:
e' turning point temperature
1. Instrument and brand thereof: DMA 850 for TA instruments
2. The preparation method of the sample comprises the following steps: the polyvinyl alcohol film was cut into a strip shape having a Mechanical Direction (MD) of 5cm and a width direction (TD) of 5mm, and the water content of the polyvinyl alcohol film was adjusted to 8 to 9wt% before feeding to the machine, so that the polyvinyl alcohol film was uniform. Next, referring to fig. 2, one end of the polyvinyl alcohol film 2 is clamped by a dovetail clamp 3 of about 1.11g, the other end is inserted into the soaking and stretching clamp 1, a part of the polyvinyl alcohol film 2 is placed between the fixed shaft 1a and the lower fixed shaft 1b, the lower end 3a of the dovetail clamp 3 is 1cm (distance a shown in fig. 2) from the soaking and stretching clamp 1, and a reserved space is reserved between the upper end 2a of the polyvinyl alcohol film 2 and the upper end of the soaking and stretching clamp 1; next, the polyvinyl alcohol film 2 is fixed by locking the upper fixing shaft 1 a. Next, referring to fig. 3, the entire immersing and stretching jig 1, together with the polyvinyl alcohol film 2 and the dovetail clamp 3 held by the jig, is vertically placed in a 100mL beaker 4 containing pure water so that the liquid surface of the beaker is positioned on the upper fixed shaft, and the temperature of the beaker 4 is controlled in a constant temperature water tank (not shown) at 30 ℃, so that the polyvinyl alcohol film 2 is swelled for 20 minutes with a load (the weight of the dovetail clamp 3). Finally, referring to fig. 4, the soaking and stretching clamp 1 is taken out from the beaker 4 and kept upright, the polyvinyl alcohol film 2 is stretched by the weight of the dovetail clamp 3, after centering of the polyvinyl alcohol film 2 is determined, the lower fixing shaft 1b of the soaking and stretching clamp 1 is locked, then the redundant polyvinyl alcohol film 2c (namely, the grid-shaped part in fig. 4) is sheared off, and the sample is the polyvinyl alcohol film 2b which is clamped in the soaking and stretching clamp 1 and swelled by load.
3. Test conditions: and (3) under the state that the sample is opened upwards and still fixed on the soaking and stretching clamp, selecting an oscillation heating mode, placing the sample and the soaking and stretching clamp clamping the sample into a soaking water tank filled with deionized water, setting the frequency to be 1Hz, setting the vibration amplitude to be 200 mu m, setting the holding pressure (force track) to be 200%, measuring the temperature from 30 ℃ to 65 ℃, stretching the film with a static force of 0.15N before analysis, analyzing at a heating rate of 1 ℃/min, and drawing a graph of storage modulus (E') versus temperature change. Wherein, thermocouple induction end is arranged in the position 5mm high from the basin bottom.
4. And (3) data processing: the coordinate axis of the storage modulus (E') is changed into a linear coordinate axis, the set analysis temperature interval is set to be 30-45 ℃ by using the set analysis built in the software attached to the instrument, and the software can automatically bring out the turning point temperature.
4. Evaluation method and results
The present invention provides methods for evaluating polyvinyl alcohol films and polarizing films of examples and comparative examples, and results corresponding to the analysis contents described above.
Evaluation of polarization degree
Test conditions: cutting a polarizing film into two square samples with the MD direction of 4 cm and the TD direction of 4 cm, overlapping the two polarizing film samples in a mode that the MD direction (namely, the flow direction) is parallel, and measuring the light transmittance (H 11) under the irradiation of light with the wavelength of 700 nanometers by using a spectrophotometer; the two polarizing film samples were then superimposed on each other in a manner perpendicular to the MD direction, and the light transmittance (H 1) was measured under irradiation of light having a wavelength of 700 nm, and calculated by the following polarization degree formula: polarization (%) = [ (H 11-H1)/(H11+H1)]1/2).
Evaluation of the value of the deterioration of the polarization degree
Test conditions: the polarizing film was put into an 80 ℃ oven for heat treatment for 500 hours, the polarization was re-measured, and the polarization decay value was calculated using the following formula: polarization degree decline value (%) = | polarization degree after heat treatment-original polarization degree|.
Further, the degree of surface swelling and the E' turning point temperature of the polyvinyl alcohol films of examples 1 to 12 and comparative examples 1 to 5 of the present invention are shown in table 2 together with the evaluation of the degree of polarization and the evaluation of the deterioration value of the degree of polarization of the corresponding polarizing films.
TABLE 2
As can be seen from table 2, in the analysis of the surface swelling degree and the temperature of the E 'turning point of the polyvinyl alcohol film samples of examples 1 to 12, the measured surface swelling degrees were all 17.0% to 38.0%, and the temperature of the E' turning point was all 37 to 40 ℃; the polarization degree of the polarization films prepared by the polyvinyl alcohol films is more than 99.99 percent, and the polarization degree degradation value is less than or equal to 0.010 percent, so that excellent polarization degree evaluation and polarization degree degradation value evaluation can be obtained. In contrast, in the analysis of the surface swelling degree and the temperature of the E 'turning point of the polyvinyl alcohol film samples of comparative examples 1 to 5, the measured surface swelling degree and the temperature of the E' turning point could not fall within the above specific ranges at the same time, and the polarization degree deterioration values of the polarizing films produced by the polyvinyl alcohol films were all greater than 0.010%, so that the ideal results could not be obtained in both the polarization degree evaluation and the polarization degree deterioration value evaluation. In view of this, only the surface swelling degree of the polyvinyl alcohol film obtained by immersing the polyvinyl alcohol film in a 4wt% boric acid solution at 55 ℃ for 1 minute is controlled to be 17.0 to 38.0%, and the storage modulus (E') of the polyvinyl alcohol film in water at 30 ℃ to 55 ℃ has a turning point temperature of 37 to 40 ℃, so that the prepared polarizing film has good polarization degree and can improve the polarization degree degradation.
Shrinkage evaluation
1. Test conditions: cutting the polarizing film into square samples with the MD direction of 10 cm and the TD direction of 10 cm, putting the square samples into an oven at 80 ℃ for heat treatment for 500 hours, taking out the square samples, returning to room temperature, measuring the lengths of the MD direction and the TD direction by using a vernier scale, and calculating to obtain the MD direction shrinkage, the TD direction shrinkage and the surface shrinkage by using the following shrinkage formulas.
2. Shrinkage in each direction (MD direction and TD direction) formula:
3. The area shrinkage formula:
Further, the TD-direction swelling degree, MD-direction swelling degree, difference in swelling degree and ratio of swelling degree (TD/MD) of the polyvinyl alcohol films of examples 1 to 12 and comparative examples 1 to 5 of the present invention are shown in table 3 together with the corresponding surface shrinkage ratio, TD-direction shrinkage ratio and MD-direction shrinkage ratio of the polarizing films.
TABLE 3 Table 3
Remarks: * Representing frangible membranes
As can be seen from table 3, the polyvinyl alcohol films of examples 1 to 12 have the characteristics of a surface shrinkage of 2% or less, a TD shrinkage of 1% or less, and an MD shrinkage of 1% or less, since the surface swelling degree, TD swelling degree, and MD swelling degree are simultaneously in the ranges of 17.0% to 38.0%,9.0% to 18.0%, and 7.5% to 18.0%, respectively. Further, it was found that, although comparative example 3 exhibited ideal surface shrinkage, TD shrinkage and MD shrinkage of the polarizing film, the results of the evaluation of the on-state polarization degree and the evaluation of the polarization degree deterioration value were poor, and thus the effects to be achieved in the present case were not yet achieved, and it was found in the course of experiments that the polyvinyl alcohol film was liable to be broken in the polarizing film process. In summary, when the surface swelling degree of the polyvinyl alcohol film is controlled to be 17.0% to 38.0%, the TD-direction swelling degree is controlled to be 9.0% to 18.0%, and the MD-direction swelling degree is controlled to be 7.5% to 18.0%, the polarizing film obtained therefrom can further have the characteristics of small shrinkage and being not easily deformed under use in a high heat environment for a long period of time.
All ranges provided herein are intended to include each specific range within the given range as well as combinations of sub-ranges between the given ranges. Moreover, unless otherwise indicated, all ranges provided herein include the endpoints of the ranges. Thus, ranges 1-5 specifically include 1, 2, 3, 4, and 5, as well as subranges such as 2-5, 3-5, 2-3, 2-4, 1-4, and the like.
All publications and patent applications cited in this specification are herein incorporated by reference and for any and all purposes, each individual publication or patent application is specifically and individually indicated to be incorporated by reference. In the event of an inconsistency between the present disclosure and any of the publications or patent applications incorporated by reference herein, the present disclosure shall control.
Symbol description
1. Soaking stretching clamp
1A upper fixed shaft
1B lower fixed shaft
2. Polyvinyl alcohol film
2A upper end
2B polyvinyl alcohol film swollen by load
2C excess polyvinyl alcohol film
3. Dovetail clamp
3A bottom end
4. Beaker
Distance a
Claims (16)
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2023133669A JP2024169263A (en) | 2023-05-24 | 2023-08-18 | Polyvinyl alcohol film and optical film produced therefrom |
| KR1020230120800A KR20240169494A (en) | 2023-05-24 | 2023-09-12 | Polyvinyl alcohol film and optical film manufactured therefrom |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US202363468543P | 2023-05-24 | 2023-05-24 | |
| US63/468,543 | 2023-05-24 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN119019737A true CN119019737A (en) | 2024-11-26 |
Family
ID=91269763
Family Applications (3)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310659561.1A Pending CN119019796A (en) | 2023-05-24 | 2023-06-06 | Polyvinyl alcohol film and optical film made therefrom |
| CN202310658893.8A Pending CN119019737A (en) | 2023-05-24 | 2023-06-06 | Polyvinyl alcohol film and optical film made therefrom |
| CN202410636343.0A Pending CN119019797A (en) | 2023-05-24 | 2024-05-22 | Polyvinyl alcohol film and optical film made therefrom |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310659561.1A Pending CN119019796A (en) | 2023-05-24 | 2023-06-06 | Polyvinyl alcohol film and optical film made therefrom |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410636343.0A Pending CN119019797A (en) | 2023-05-24 | 2024-05-22 | Polyvinyl alcohol film and optical film made therefrom |
Country Status (4)
| Country | Link |
|---|---|
| JP (2) | JP2024169264A (en) |
| KR (2) | KR20240169494A (en) |
| CN (3) | CN119019796A (en) |
| TW (3) | TWI837013B (en) |
Family Cites Families (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60245586A (en) * | 1984-05-21 | 1985-12-05 | Canon Inc | Recording material |
| TWI247771B (en) * | 2000-05-01 | 2006-01-21 | Kuraray Co | Process for producing polyvinyl alcohol-based polymer film and polarizing film |
| US7745517B2 (en) * | 2006-05-02 | 2010-06-29 | Sekisui Specialty Chemicals America, Llc | Polyvinyl alcohol films with improved resistance to oxidizing chemicals |
| JP2007316366A (en) * | 2006-05-26 | 2007-12-06 | Nippon Shokubai Co Ltd | Polarizer protective film, polarizing plate, and image display device |
| JP5058953B2 (en) * | 2007-12-06 | 2012-10-24 | 日東電工株式会社 | Manufacturing method of optical display unit and roll material used therefor |
| TWI374895B (en) * | 2008-11-19 | 2012-10-21 | Ind Tech Res Inst | Polyvinyl alcohol film composition, and polarizer plate employing the same |
| TWI384025B (en) * | 2009-04-27 | 2013-02-01 | Ind Tech Res Inst | Polyvinyl alcohol film composition, and polarizer plate employing the same |
| TWI689547B (en) * | 2014-10-13 | 2020-04-01 | 美商摩諾索公司 | Water-soluble polyvinyl alcohol film with plasticizer blend, related methods and related articles |
| KR20160043765A (en) * | 2014-10-14 | 2016-04-22 | 스미또모 가가꾸 가부시키가이샤 | Polarizer and preparing method thereof |
| WO2017033552A1 (en) * | 2015-08-26 | 2017-03-02 | 日本合成化学工業株式会社 | Polyvinyl alcohol resin for production of polarizing film, method for producing same, polyvinyl alcohol film, method for producing polyvinyl alcohol film, polarizing film and polyvinyl alcohol resin |
| JP6834956B2 (en) * | 2016-05-27 | 2021-02-24 | 三菱ケミカル株式会社 | A polyvinyl alcohol-based film, a method for producing the same, and a polarizing film using the polyvinyl alcohol-based film. |
| CN106751264B (en) * | 2016-09-18 | 2019-10-11 | 南京林业大学 | A kind of carbon nanotube-nanocellulose-polyvinyl alcohol composite conductive gel and its preparation method and application |
| CN111868584B (en) * | 2018-03-30 | 2022-11-18 | 积水化学工业株式会社 | Production method of polyvinyl alcohol film and polarizing film |
| TWI803672B (en) * | 2018-07-31 | 2023-06-01 | 日商三菱化學股份有限公司 | Polyvinyl alcohol-based film and polarizing film |
| CN109593221B (en) * | 2018-10-24 | 2021-07-30 | 北京印刷学院 | Polyvinyl alcohol film, post-processing method and preparation method of polyvinyl alcohol film |
| WO2020184657A1 (en) * | 2019-03-14 | 2020-09-17 | 株式会社クラレ | Adhesive and polarizing plate |
| JPWO2022202861A1 (en) * | 2021-03-24 | 2022-09-29 | ||
| JP7228722B1 (en) * | 2021-10-08 | 2023-02-24 | 長春石油化學股▲分▼有限公司 | POLYVINYL ALCOHOL FILM, OPTICAL FILM CONTAINING THE SAME, AND METHOD OF PRODUCING THEM |
| TWI792963B (en) * | 2022-03-28 | 2023-02-11 | 長春石油化學股份有限公司 | Polyvinyl alcohol film, optical film produced by the same, and manufacturing method thereof |
-
2023
- 2023-06-06 TW TW112121004A patent/TWI837013B/en active
- 2023-06-06 CN CN202310659561.1A patent/CN119019796A/en active Pending
- 2023-06-06 CN CN202310658893.8A patent/CN119019737A/en active Pending
- 2023-06-06 TW TW112121003A patent/TWI843593B/en active
- 2023-08-18 JP JP2023133674A patent/JP2024169264A/en active Pending
- 2023-08-18 JP JP2023133669A patent/JP2024169263A/en active Pending
- 2023-09-12 KR KR1020230120800A patent/KR20240169494A/en active Pending
- 2023-09-12 KR KR1020230120794A patent/KR20240169493A/en active Pending
-
2024
- 2024-05-22 CN CN202410636343.0A patent/CN119019797A/en active Pending
- 2024-05-22 TW TW113118901A patent/TWI859105B/en active
Also Published As
| Publication number | Publication date |
|---|---|
| KR20240169494A (en) | 2024-12-03 |
| TW202446862A (en) | 2024-12-01 |
| TWI843593B (en) | 2024-05-21 |
| TWI837013B (en) | 2024-03-21 |
| CN119019796A (en) | 2024-11-26 |
| KR20240169493A (en) | 2024-12-03 |
| JP2024169264A (en) | 2024-12-05 |
| TW202446853A (en) | 2024-12-01 |
| TWI859105B (en) | 2024-10-11 |
| JP2024169263A (en) | 2024-12-05 |
| TW202446854A (en) | 2024-12-01 |
| CN119019797A (en) | 2024-11-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106226858B (en) | Polyvinyl alcohol film and light polarizing film | |
| CN109153797B (en) | Polyvinyl alcohol film, method for producing same, and polarizing film using same | |
| TWI395773B (en) | Crosslinkable, cellulose ester compositions and films formed therefrom | |
| JP7234105B2 (en) | Polarizing film, polarizing plate, and manufacturing method thereof | |
| WO2019189695A1 (en) | Poly(vinyl alcohol) film and production method for polarizing film | |
| KR20200136914A (en) | Polyvinyl alcohol film and manufacturing method of polarizing film | |
| JP6883990B2 (en) | Polyvinyl alcohol-based film, method for producing polyvinyl alcohol-based film, and polarizing film | |
| WO2019189693A1 (en) | Poly(vinyl alcohol) film and production method for polarizing film | |
| JP2024170637A (en) | Polyvinyl alcohol film and optical film produced therefrom | |
| TW202216806A (en) | Polyvinyl alcohol film and polarizing film in which same is used | |
| CN119019737A (en) | Polyvinyl alcohol film and optical film made therefrom | |
| CN119065047A (en) | Method for manufacturing polarizing plate | |
| KR102742997B1 (en) | Polyvinyl alcohol film and an optical film produced therefrom | |
| TWI888216B (en) | Polyvinyl alcohol film and optical film produced therefrom | |
| TWI527849B (en) | Cellulose triacetate films with low birefringence | |
| CN115996974A (en) | Polyvinyl alcohol film and method for producing optical film using same | |
| KR102871599B1 (en) | Polyvinyl alcohol film and optical film manufactured therefrom | |
| KR101765793B1 (en) | Manufacturing method of Cellulose ester Film | |
| TWI870317B (en) | Polyvinyl alcohol film, optical film comprising the same and manufacturing method thereof | |
| TWI874712B (en) | Method for producing polarizing film | |
| JP2024169407A (en) | Polyvinyl alcohol film and optical film produced therefrom | |
| TW202400694A (en) | Polyvinyl alcohol-based films, polarizing films using the same, and polarizing plates | |
| JP2005106929A (en) | Polymeric film, protective film for polarizer, and liquid crystal display device | |
| KR20160092985A (en) | High-contrast polarization element exhibiting uniform transmittance at respective wavelengths, and polarization plate | |
| KR20170090924A (en) | Manufacturing method of cellulose ester film having improved polarizer light-leakage property |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication |