POLARIZING PLATE PROTECTIVE FILM AND POLARIZING PLATE INCLUDING THE SAME

• Main Authors: TAKIMOTO MASATAKA, TAMAGAWA YOSHINORI
• Format: Patent
• Language: English; Japanese
• Published: 10.09.2015
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; FREQUENCY-CHANGING; GENERAL PROCESSES OF COMPOUNDING; METALLURGY; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; ORGANIC MACROMOLECULAR COMPOUNDS; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

PROBLEM TO BE SOLVED: To provide a polarizing plate protective film having a high stress at break and bending strength, and a polarizing plate including the polarizing plate protective film and having excellent reworkability.SOLUTION: The polarizing plate protective film comprises at least a resin (A) and a resin (B) having different degrees of solubility with an organic solvent from each other, and has a film thickness of 15 to 100 μm. In an evaluation test of solubility in a given amount of a resin, in a given amount of a solvent, and at a given temperature, the polarizing plate protective film exhibits the following characteristics: when the polarizing plate protective film is dissolved under given conditions by using a solvent (a), which is a good solvent with respect to the resin (A) but is a poor solvent with respect to the resin (B), in at least a minimum amount necessary to solely and completely dissolve the resin (A), an undissolved portion is left in the polarizing plate protective film, and a mass of the resin (A) included in the undissolved portion is 10% or more with respect to the mass of the resin (A) included in the polarizing plate protective film before dissolution. 【課題】破断点応力と折り曲げ強度が高い偏光板保護フィルムの提供と、その偏光板保護フィルムが具備されたリワーク性の優れた偏光板を提供する。【解決手段】有機溶媒に対する溶解性が相異する少なくとも樹脂Ａ及び樹脂Ｂを含有する膜厚が１５〜１００μｍの範囲内の偏光板保護フィルムであって、一定量の樹脂、一定量の溶媒及び一定温度における溶解性の評価試験において、前記樹脂Ａに対しては良溶媒であるが、前記樹脂Ｂに対しては貧溶媒となる溶媒ａを、当該樹脂Ａを単独で完全に溶解するために要する少なくとも最低量を用いて、一定条件下で溶解したとき、不溶解部が残り、かつ当該不溶解物中に含まれる当該樹脂Ａの質量が、当該溶解前の前記偏光板保護フィルム中に含有されていた樹脂Ａの質量に対して１０％以上であることを特徴とする偏光板保護フィルム。【選択図】なし