JP2020160462A5

JP2020160462A5 -

Info

Publication number: JP2020160462A5
Application number: JP2020099437A
Authority: JP
Filing date: 2020-06-08
Publication date: 2021-02-12

Claims

One or both sides of a polyvinyl alcohol-based polarizer having a thickness of 10 μm or less and a polyvinyl alcohol-based polarizer in which the polyvinyl alcohol-based resin is oriented in one direction and iodine or a bicolor dye is adsorbed and oriented on the polyvinyl alcohol-based resin. In addition, the reinforcing film has a reinforcing film in close contact with the polyvinyl alcohol-based polarizer , and the reinforcing film is a product of a polyurethane-based material, a UV-curable material containing a urethane acrylate oligomer, or an aqueous resin emulsion material, and wherein after the polyvinyl alcohol resin is subjected to the following bending retention test for holding bent in a direction orthogonal to the alignment direction and the alignment direction oriented, with bent shape in either direction is maintained, cracks A flexible polarizing film characterized in that it does not occur.
<Bending holding test>
A rectangular object (flexible polarizing film) of 200 mm (absorption axis direction) x 300 mm (transmission axis direction) is installed on a horizontal table. Next, after folding the rectangular object in three in the transmission axis direction (long axis direction), a load of 100 g is applied so that a load is applied to the entire upper surface, and the rectangle is left for 5 minutes. After that, the load is removed.
Also, for a rectangular object (flexible polarizing film) of 200 mm (transmission axis direction) x 300 mm (absorption axis direction), the same operation as described above (however, the sample was folded in three in the absorption axis direction (long axis direction)) was performed. went.
After the folding holding test, visually check whether the sample is held in the tri-folded state, and if the tri-folded shape is maintained, return the sample to the original state (flat surface) and visually evaluate it. To do. The evaluation is performed three times for each of the samples on the long side in the transmission axis direction and the long side in the absorption axis direction.

In the following bending resistance test in the direction in which the polyvinyl alcohol resin is perpendicular to the alignment direction and the alignment direction oriented, flexible according to claim 1, wherein the bending resistance (mm) is equal to or is 60mm or less Polarizing film.
<Rigidity test>
No. made by Yasuda Seiki Seisakusho A 476 cantilever type flexibility tester is used. Further, in this test, in order to eliminate the influence of static electricity, the flexible polarizing film used in the test was appropriately statically eliminated.
A rectangular object (flexible polarizing film) of 50 mm (absorption axis direction) x 150 mm (transmission axis direction), with a flat top (50 mm x 150 mm: the same size as the flexible polarizing film), and a 45 ° slope at one end of the long side. It is installed so that it fits on the top surface of the SUS plate base 41, which has a smooth trapezoidal cross section. The flexible polarizing film was installed so that there was a slope in the transmission axis direction.
The flexible polarizing film is gently slid and moved to the slope side at an extrusion speed of 10 mm / sec (1). The movement of the flexible polarizing film was stopped at the point where the tip of the flexible polarizing film first touched the slope (2). The distance L (mm) that the sample has moved when the top is flat is measured.
A rectangular object (flexible polarizing film) of 50 mm (transmission axis direction) × 150 mm (absorption axis direction) was subjected to the same operation as described above (however, the flexible polarizing film was installed so that there was a slope in the absorption axis direction). ..
The rigidity (mm) is the shortest linear distance three times for each of the two patterns when the first surface is on the upper side and the second surface is on the upper side for the samples on the long side in the transmission axis direction and the long side in the absorption axis direction. L (mm) is measured (12 samples in total) and used as their arithmetic mean value.
If there is a sample that cannot be measured due to deformation or curl of the sample in any one or more measurements of the 12 samples, it is determined that the sample cannot be measured.

The flexible polarizing film according to claim 1 or 2 , wherein in the tensile test, the tensile strength in the direction orthogonal to the orientation direction in which the polyvinyl alcohol-based resin is oriented is 5 N / 10 mm or more.

The polyvinyl alcohol-based polarizer has optical characteristics represented by a simple substance transmittance T and a degree of polarization P of the following formula P>-(10 ^{0.929T-42.4-1} ) × 100 (however, T <42. 3) or
The flexible polarizing film according to any one of claims 1 to 3 , wherein the flexible polarizing film is configured to satisfy the condition of P ≧ 99.9 (however, T ≧ 42.3).

The flexible polarizing film according to any one of claims 1 to 4 , wherein the reinforcing film on at least one surface has a thickness of 15 μm or less.

Wherein a polyvinyl alcohol-based first one side thickness 15μm below the first reinforcing layer of the polarizer, according to claim 5, characterized by having the following second reinforcing film thickness 15μm on a second side of the other Flexible polarizing film.

The flexible polarizing film according to claim 6, wherein the thickness difference between the first reinforcing film and the second reinforcing film is 10 μm or less.

The flexible polarizing film according to any one of claims 1 to 7 , wherein the ratio of the thickness of the reinforcing film to the thickness of the polyvinyl alcohol-based polarizer is 0.4 or more.

The flexible polarizing film according to any one of claims 1 to 8 , wherein the reinforcing film has a compressive elastic modulus at 23 ° C. of 1 MPa or more.

The flexible polarizing film according to any one of claims 1 to 9 , wherein the reinforcing film is not substantially oriented.

The method for producing a flexible polarizing film according to any one of claims 1 to 10 .
Step (1) of preparing a polyvinyl alcohol-based polarizer having a thickness of 10 μm or less, in which the polyvinyl alcohol-based resin is oriented in one direction and iodine or a dichroic dye is adsorbed and oriented on the polyvinyl alcohol-based resin.
A liquid material containing a polyurethane material, a UV curable material containing a urethane acrylate oligomer, or an aqueous resin emulsion material is applied to at least one surface of the polyvinyl alcohol-based polarizer, and then the liquid material is solidified or cured. A method for producing a flexible polarizing film, which comprises a step (2) of forming a reinforcing film.

An image display device having the flexible polarizing film according to any one of claims 1 to 10 .