Method for manufacturing polarizer and polarizer manufactured by the same
The present specification relates to a method for manufacturing a polarizer and a polarizer manufactured by using the same, and more particularly, to a method for manufacturing a polarizer, which includes a cross-linking and elongating step using an aqueous solution including a polyvalent carboxylic acid compound and a boric acid compound, and a polarizer manufactured by using the same.
1. A method for manufacturing a polarizer, the method comprising:
a step of dyeing at least one dye of iodine and dichromatic dyes on a polyvinyl alcohol-based film;
a first cross-linking and elongating step of cross-linking and elongating the polyvinyl alcohol-based film and the dye by using a first aqueous solution including a polyvalent carboxylic acid compound and a boron compound;
a second cross-linking and elongating step of cross-linking and elongating the polyvinyl alcohol-based film and the dye by using a second aqueous solution including the polyvalent carboxylic acid compound and the boron compound; and
a step of drying the polyvinyl alcohol-based film,
wherein the first cross-linking and elongating step and the second cross-linking and elongating step satisfy the following Equations (1) and (2):
0.2 ≤X+Y≤ 3 Equation (1):
0.01≤XY≤2.25 Equation (2):
in Equations (1) and (2),
X is [a content of the polyvalent carboxylic acid compound of the first aqueous solution]/[a content of the boron compound of the first aqueous solution] of the first cross-linking and elongating step, and
Y is [a content of the polyvalent carboxylic acid compound of the second aqueous solution]/[a content of the boron compound of the second aqueous solution] of the second elongating and cross-linking step,
wherein the first and second aqueous solution each independently includes the polyvalent carboxylic acid compound in a content of 10 wt % to 150 wt % based on 100 wt % of the boron compound.
2. The method of claim 1 , wherein the boron compound is included in a content of 0.5 wt % to 10 wt % based on 100 wt % of each of the first and second aqueous solutions.
3. The method of claim 1 , wherein the polyvalent carboxylic acid compound is one kind or more selected from the group consisting of glutaric acid, succinic acid, malonic acid, oxalic acid, 1,2,3,4-butane tetracarboxylic acid, citric acid, malic acid, tartaric acid, and a derivative thereof.
4. A polarizer manufactured by the method of claim 1 .
5. A polarizing plate comprising:
the polarizer of claim 4 .
6. An image display device comprising:
a display panel; and
the polarizing plate of claim 5 attached to one surface or both surfaces of the display panel.