KR101992004B1 - Polarizer, method for preparing the same, polarizing plate comprising the same and display apparatus comprising the same - Google Patents

Abstract

A polarizer containing iodine as a dichroic substance and containing iodine anion I ^- in an amount of 0.20 wt% or less, a process for producing the same, a polarizing plate including the polarizer, and a display device including the same are provided.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarizer, a polarizer, a polarizer, and a display device including the polarizer. 2. Description of the Related Art Polarizers,

The present invention relates to a polarizer, a method for producing the same, a polarizing plate including the polarizer, and a display device including the same.

The polarizing plate includes a polarizer, a protective film formed on the polarizer, and / or a retardation film. The polarizer can be produced by dying, stretching or the like with a dichroic material. Although not particularly limited, the polarizer can be produced by further washing, swelling, crosslinking, and complementary steps in addition to the step of dyeing and drawing. The complementary process improves the optical characteristics of the polarizer by adjusting the color value of the polarizer.

As the dichroic material, iodine-based dyes are usually used. As known to those skilled in the art, when an iodine dye is dyed on a polyvinyl alcohol-based film, a polyvinyl alcohol-iodine anion I ^- complex is formed by stretching, and polyvinyl alcohol and I ₃ ^- or polyvinyl alcohol and I ₅ ^- ≪ / RTI > However, in the course of the production of the polarizer, the iodine anion I ^- which can not form a complex with polyvinyl alcohol remains. These residual iodine anions I ^- may react with I ₃ ^- or I ₅ ^- already complexed with polyvinyl alcohol at high temperature or high temperature and high humidity, thereby deteriorating the optical characteristics of the polarizer and lowering the reliability by changing the color value . Therefore, it is important to prevent residual iodine anions I ^{- in} the polarizer.

The background art of the present invention is disclosed in Japanese Laid-Open Patent Application No. 2013-101301.

A problem to be solved by the present invention is to provide a polarizer capable of improving the durability of the polarizing plate by lowering the amount of change in the degree of polarization and the amount of change in color value after being left at high temperature or high temperature and high humidity.

Another problem to be solved by the present invention is to provide a polarizer capable of improving the quality of a display screen due to its low color value.

Another object to be solved by the present invention is to provide a polarizer having an antistatic function.

Another problem to be solved by the present invention is to provide a polarizer excellent in durability due to low change in polarization degree and amount of change in hue value after being left at high temperature or high temperature and high humidity.

The polarizer of the present invention may be a polarizer containing iodine as a dichroic substance and containing iodine anion I ^- in an amount of 0.20 wt% or less.

The method for producing a polarizer according to the present invention comprises a step of performing a complementary treatment on a polyvinyl alcohol film which has been subjected to a dyeing treatment and a stretching treatment, wherein the complementary coloring treatment is carried out by using a complementary coloring solution containing at least one of the compounds represented by the following general formula (1) Treating the polyvinyl alcohol-based film with the drawn and drawn polyvinyl alcohol film.

[Chemical Formula 1]

_{^{M + [R-SO 2 -O}} ] -

(2)

M ⁺ [R ¹ -SO ₂ -N-SO ₂ -R ² ] ^-

(Wherein M ⁺ , R, R ¹ , R ² are as defined in the Detailed Description of the Invention).

The polarizing plate of the present invention may include a polarizer of the present invention and an optical film formed on at least one side of the polarizer.

The display device of the present invention may include the polarizer of the present invention or the polarizing plate of the present invention.

The present invention provides a polarizer capable of improving the durability of a polarizing plate because the amount of change in polarization degree and the amount of change in hue value after being left at high temperature or high temperature and high humidity are low.

The present invention provides a polarizer capable of improving display screen quality because of low color value.

The present invention provides a polarizer having an antistatic function.

The present invention provides a polarizer excellent in durability due to a change in polarization degree and a change in hue value after being left at high temperature or high temperature and high humidity.

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

In the present specification, the substitution in "substituted or unsubstituted" means that at least one hydrogen atom of the corresponding functional group is substituted with a hydroxyl group (OH), an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or halogen.

As used herein, "halogen" means F, Cl or Br.

Hereinafter, a polarizer according to an embodiment of the present invention will be described.

The polarizer according to this embodiment may contain iodine as a dichroic substance and the polarizer may contain iodine anion I ^- in an amount of 0.20 wt% or less. In this range, the content of iodine anions I ^- remaining in the polarizer is low, thereby inhibiting the reaction between the iodine anion I ^- and the iodine anion I ₃ ^- or I ₅ ^- already bound to the polyvinyl alcohol even if the polarizer is left at high temperature or high temperature and high humidity. The durability of the polarizer can be enhanced. The iodine anion I ₃ ^- or I ₅ ^- is bonded to polyvinyl alcohol to exhibit the polarizing property of the polarizer. Therefore, when the iodine anion I ₃ ^- or I ₅ ^- is separated from the polyvinyl alcohol, the polarization of the polarizer may deteriorate and the hue value may be changed. Preferably, the content of the iodine anions I < ^- > in the polarizer may be 0 wt% or more and 0.18 wt% or less.

The content of the iodine anions I < ^- > in the polarizer can be measured by a conventional method known to a person skilled in the art.

On the other hand, the polarizer may have an absolute value of the color value bc of 3 or less, specifically 2 or less, more specifically 1.5 or less at a wavelength of 380 nm to 780 nm. It is possible to solve the problem that the display screen is displayed in blue color when mounted on the display in the above range and to prevent the occurrence of light leakage for short-wavelength light.

As described above, the polarizer can reduce the absolute value of the color value bc and the content of the iodine anion I ^- by the complementary color process described below, thereby improving the durability of the polarizing plate at high temperature or high temperature and high humidity. The "bc value" is measured using a reference polarizing plate having a degree of polarization of 99.990% or more, and the absorption axis of the reference polarizing plate and the absorption axis of the polarizer of the present invention are orthogonal to each other, and by the CIE LAB color coordinate reference for wavelengths of 380 to 780 nm It can be the measured orthogonal bc value. The "reference polarizing plate" may be one which is in the measurement apparatus of the orthogonal bc value. Specifically, the color value bc of the polarizer may be -3 to +2, specifically -2 to +1, preferably -0.5 to +0.5. It is possible to solve the problem that the display screen is displayed in blue color when mounted on the display in the above range and to prevent the occurrence of light leakage for short-wavelength light.

The polarizer according to this embodiment can be produced by injecting a compound for removing the iodine anion I < ^- > into the complementary process during the production process of the polarizer, as in the process for producing a polarizer described below. The complementary process is for adjusting the color value of the polarizer as known to those skilled in the art. A polarizer according to this embodiment is the iodide I ^- prepared by reducing at the same time ^- in Iodide (I) for removing adjusting the color values of the polarizer by charging the formula (I) or a compound of the formula (2) a complementary process to the polarizer will be. Accordingly, it is possible to lower the amount of change in polarization degree upon leaving the polarizer at high temperature or high temperature and high humidity of the polarizer of the present invention, and to lower the amount of change in color value, thereby improving durability.

Specifically, the polarizing plate may have a variation degree of polarization degree of 3% or less, for example, 0% or more and 2% or less, or 0% or less and 0.2% or less. In the above range, the durability of the polarizing plate is good and the reliability can be improved. The polarizing plate can have a hue change amount of 3 or less, for example, 0 or more and 3 or less, or 0 or more and 2 or less at a wavelength of 380 to 780 nm . Within the above range, the durability and reliability of the polarizing plate can be improved:

<Formula 1>

Change in polarization degree = P ₂ - P ₁ |

(In the above formula 1,

P ₁ is an initial polarization degree (unit:%) of the polarizing plate,

P ₂ is the degree of polarization (unit:%) after the polarizing plate was left at 85 ° C for 500 hours.

<Formula 2>

Change in color value = bc ₂ - bc ₁ |

(In the above formula 2,

bc ₁ is the initial color value of the polarizer,

bc ₂ is the hue value after leaving the polarizing plate at 85 캜 for 500 hours)

In the formula 2, bc ₁ and bc ₂ may have an absolute value of 3 or less, specifically 2 or less, more specifically 1.5 or less. In addition, ₁ bc, bc ₂ may be each more than +2 -3 or less, more specifically more than -2 +1 or less, preferably -0.5 or less than +0.5. It is possible to solve the problem that the display screen is displayed in blue color when mounted on the display in the above range and to prevent the occurrence of light leakage for short-wavelength light.

On the other hand, the polarizer of the present invention may have an antistatic function. Therefore, the surface resistance of the polarizer may be 2.0 x ¹⁰ &lt; ¹⁰ &gt; / [gamma] or less, for example, 8.5 x ¹⁰ &lt; ⁹ & Even if the polarizer is wound on the roll in the production of the polarizer using the polarizer in the above range, the processability may be good.

It may comprise a combination of anionic and K ⁺ cations of the compounds for the removal ^of-the polarizer Iodide I. Specifically, the compound for removing the iodine anion I ^- may be a salt of a metal monovalent cation (M ⁺ ion) and a sulfate anion or a sulfonamide anion described below . The iodide I ^- When the compound for removing In a complementary process to be decomposed by the water above metal is monovalent cation (M ⁺ ion) and the following Formula 1-1 or a sulfate anion of formula 1-2 generating a sulfonamide anion, typically K ⁺ ion and iodide I in a polarizer included in a complementary ^step-may comprise the combination of the ion exchange reaction the by sulfate anion or a sulfonamide anion and K ⁺ cations between the water within the polarizer have. Even if the conjugate is included, the polarization degree, transmittance and color value of the polarizer are not affected. Also, through this, the polarizer may exhibit antistatic performance.

&Lt; Formula 1-1 >

[R-SO ₂ -O] ^-

(1-2)

[R ¹ -SO ₂ -N-SO ₂ -R ² ] ^-

(Wherein R represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted carbon number An arylalkyl group having 7 to 20 carbon atoms, or a substituted or unsubstituted alkoxy group having 1 to 10 carbon atoms

R ¹ and R ² are each independently selected from the group consisting of halogen, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, A substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms).

The polarizer may have a thickness of 1 占 퐉 to 20 占 퐉, more specifically, 3 占 퐉 to 13 占 퐉. In the above range, a thin polarizer can be used for a display device.

Hereinafter, a method of manufacturing a polarizer according to an embodiment of the present invention will be described.

The method for producing a polarizer according to the present embodiment includes a step of performing a complementary treatment on a polyvinyl alcohol film that has been subjected to a dyeing process and a stretched polyvinyl alcohol film, wherein the complementary color process is a complementary process including at least one of the following chemical formula 1 or 2 and potassium iodide Treating the drawn and stretched polyvinyl alcohol-based film in a sub-color bath containing the liquid:

[Chemical Formula 1]

_{^{M + [R-SO 2 -O}} ] -

(2)

M ⁺ [R ¹ -SO ₂ -N-SO ₂ -R ² ] ^-

(Wherein M ⁺ is R ^a R ^b R ^c R ^d N ⁺ , Li ⁺ or Na ⁺ , wherein R ^a , R ^b , R ^c and R ^d are each independently hydrogen, a substituted or unsubstituted carbon number An alkyl group having 1 to 10 carbon atoms or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms,

R represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted 7 to 20 carbon atoms An arylalkyl group, or a substituted or unsubstituted C1-C10 alkoxy group

R ¹ and R ² are each independently selected from the group consisting of halogen, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, A substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms).

Preferably, R may be an alkoxy group having 1 to 10 carbon atoms, more preferably an alkoxy group having 1 to 5 carbon atoms, e.g., a methoxy group.

Preferably, M ⁺ can be R ^a R ^b R ^c R ^d N ⁺ . M ⁺ can be a monoalkylammonium cation, a dialkylammonium cation, a trialkylammonium cation, or a tetraalkylammonium cation. R ^a , R ^b , R ^c and R ^d each independently represent a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms. More preferably, each of R ^a , R ^b , R ^c and R ^d independently represents an unsubstituted alkyl group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms substituted with a hydroxyl group, An alkyl group having 1 to 5 carbon atoms substituted with an alkoxy group.

Specifically, the compound of Chemical Formula 1 may be prepared by reacting N, N-bis (2-hydroxyethyl) -N- (3'-dodecyloxy-2'-hydroxypropyl) -N-methylammonium methosulfate 609, Cytec.), And the like, but are not limited thereto. The compounds of the formula (II) bis (trifluoromethane sulfonyl) imide sodium (NaN (CF ₃ SO _{2) 2),} bis (trifluoromethane sulfonyl) imide lithium (LiN (CF ₃ SO _{2) 2} ), Bis (fluorosulfonyl) imide sodium (NaN (FSO ₂ ) ₂ ), and the like.

The compounds of formula (1) or (2) may be commercially available products or may be prepared by conventional methods known to those skilled in the art.

The invention Iodide I in the polarizer added by adding the compound of formula (1) or (2) a complementary pair of complementary color ^liquid-could also meet the same time the color values of the polarizer due to the complementary color process as well as to improve durability by removing the. The compound of formula (1) is decomposed by a solvent, for example, water in the boron coloration tank to produce M ⁺ cations and [R-SO ₂ -O] ^- anions. In the complementary process, KI is usually included. KI produces positive ions K ⁺ and negative ions I ^- in the subgraph. It can be removed ^- I iodide in the polarizer through an ion exchange reaction as described below between a ^cation K ⁺ and an anion of iodine in the polarizer I:

i) M ⁺ [R-SO ₂ -O] ^- + H ₂ O -> M ⁺ + [R-SO ₂ -O] ^-

ii) M ⁺ + [R-SO ₂ -O] ^- + K ⁺ + iodine anion in polarizer I ^- -> M ⁺ Iodine anion in the polarizer I ^- + K ⁺ ... [R-SO ₂ -O] ^-

At least one of the compounds of Formula 1 or Formula 2 may be contained in the complementary color solution in an amount of 0.005 wt% to 3 wt% and potassium iodide in an amount of 0.5 wt% or more to 7 wt% or less. In the above range, the iodine anion I &lt; ^- &gt; in the polarizer can be removed to improve the durability and the color value of the polarizer.

Hereinafter, a method for producing the polarizer will be described in more detail.

Polarizers can be prepared by dyeing, stretching, crosslinking, and complementary processes. In the method for producing the polarizer of the present invention, the order of the solidification and stretching is not limited. That is, the polyvinyl alcohol film may be stretched after the polyvinyl alcohol film is dyed, the polyvinyl alcohol film may be dyed after the stretching, and the dyeing and stretching may be simultaneously performed.

As the polyvinyl alcohol film, conventionally used polyvinyl alcohol films used in the production of polarizers can be used. Specifically, films formed of polyvinyl alcohol or derivatives thereof can be used. The polymerization degree of polyvinyl alcohol may be from 1,000 to 5,000, the saponification degree may be from 80 mol% to 100 mol%, the thickness may be from 1 탆 to 30 탆, specifically from 3 탆 to 30 탆, , And can be used for producing a thin polarizer.

The polyvinyl alcohol film can be subjected to washing with water and swelling before being dyed and stretched. The polyvinyl alcohol film can be washed with water to remove foreign matters on the surface of the polyvinyl alcohol film. By subjecting the polyvinyl alcohol film to swelling treatment, it is possible to cause the polyvinyl alcohol film to be better stained or stretched. The swelling treatment can be carried out by leaving the polyvinyl alcohol film in an aqueous solution of the swelling bath as known to those skilled in the art. The temperature and swelling time of the swelling bath are not particularly limited. The swelling bath may further contain boric acid, inorganic acid, a surfactant and the like, and the content thereof may be adjusted.

A dichroic substance can be dyed on a polyvinyl alcohol film by dying a polyvinyl alcohol film in a dichroic substance-containing salt combination. In the dyeing process, the polyvinyl alcohol film is immersed in the dyeing solution. The dyeing solution may be an aqueous solution containing an iodine dye. Specifically, the iodine-based dye may be potassium iodide, hydrogen iodide, lithium iodide, sodium iodide, zinc iodide, lithium iodide, aluminum iodide, lead iodide, copper iodide and the like. The dipping solution may be an aqueous solution containing 1 to 5% by weight of a dichroic substance. Within this range, a certain range of polarization degrees can be used in the display.

The temperature of the dye bath may be 20 to 45 캜, and the salt-bath immersion time of the polyvinyl alcohol film may be 10 to 300 seconds. A polarizer having a high degree of polarization in the above range can be realized.

By stretching the polyvinyl alcohol film in a stretching tank, the polyvinyl alcohol film can have a polarizing property by orienting the dichroic substance. More specifically, drawing can be performed both by dry drawing and wet drawing. The dry stretching may be interlaced stretching, compression stretching, heating roll stretching, or the like, and wet stretching may be performed in a wet stretching bath containing 35 to 65 占 폚 water. The wet stretching bath may further include boric acid to enhance the stretching effect.

The polyvinyl alcohol film can be stretched at a predetermined stretching ratio, specifically, stretched so that the total stretching ratio is 5 to 7 times, specifically, 5.5 to 6.5 times, and the stretching ratio of the polyvinyl alcohol film stretched in the above range , Wrinkles and the like can be prevented, and a polarizer having high polarization and high transmittance can be realized. The stretching may be uniaxial stretching by stretching in one stage but stretching in multiple stages such as two or three-stage stretching may also prevent thinning while producing a polarizer.

In the above description, the polyvinyl alcohol film is drawn and then stretched. However, the dyeing and stretching of the dichroic material may be performed in the same reaction tank.

The drawn polyvinyl alcohol film may be subjected to a crosslinking treatment in a crosslinking tank before or after the stretching of the polyvinyl alcohol film. The crosslinking is a step of allowing the dichroic material to be more strongly stained on the polyvinyl alcohol film, and boric acid may be used as the crosslinking agent. A phosphoric acid compound, potassium iodide and the like may be further added to improve the crosslinking effect.

The stained and stretched polyvinyl alcohol-based films can be complemented in a complementary tint.

The complementary color treatment is to immerse the colored and drawn polyvinyl alcohol film in a sub-coloring tank containing a complementary liquid containing at least one of the compounds of the above formula (1) or (2) and potassium iodide. Through this, the color value of the polarizer can be lowered and the iodine anion I ^- in the polarizer can be removed to improve durability.

The compound of Formula 1 and the compound of Formula 2 are as described above. At least one of the compounds of Formula 1 or Formula 2 may be contained in an amount of not less than 0.005 wt% and not more than 3 wt% of the complementary coloring solution. In this range, not only the color value of the polarizer is improved but also the durability is improved by removing the iodine anion in the polarizer, and an antistatic effect can be obtained. Preferably, at least one of the compounds of Formula 1 or Formula 2 may be contained in an amount of 0.005 wt% or more and 0.2 wt% or less of the complementary coloring solution.

The iodide may be the same as or different from the one used in the step of saponification. For example, the iodide may comprise potassium iodide. The iodide may be contained in an amount of not less than 0.5 wt% and not more than 7 wt% of the complementary color solution. Within this range, not only the color value of the polarizer is improved, but also the durability can be improved by removing the iodine anion in the polarizer. Preferably, the iodide may be contained in an amount of 1 wt% or more and 5 wt% or less of the complementary coloring solution.

The compound of formula (1) and the compound of formula (2) are not limited in shape, but may be in salt form. Accordingly, the complementary liquid may include water alone used as a solvent, or may further include an organic solvent mutually soluble with water.

The temperature of the complementary color bath may be 20 ° C to 45 ° C and the boil-off bath immersion time of the polyvinyl alcohol film may be 10 seconds to 300 seconds.

Hereinafter, a polarizing plate according to an embodiment of the present invention will be described.

The polarizing plate according to this embodiment may include a polarizer according to an embodiment of the present invention, and an optical film formed on at least one side of the polarizer. The polarizing plate includes the polarizer of the present invention. Therefore, the polarizing plate has a low change in the degree of polarization of the formula (1). Also, the polarizing plate has a low change in the hue value of the formula (2). Therefore, reliability at high temperature or high temperature and high humidity can be improved. The polarizing plate may have a change in polarization degree of 3% or less, for example, 0% or more and 2% or less, or 0% or more and less than 0.2%. In the above range, the durability of the polarizing plate is good, and the reliability can be improved. The polarizing plate may have a color value change amount of 3 or less, for example, 0 or more and 3 or less, 0 or more and 2 or less at a wavelength of 380 to 780 nm . Within the above range, the durability and reliability of the polarizing plate can be improved.

The optical film is a transparent optical film, and may be a polyester type, a cyclic polyolefin type, a polytype type, a polyimide type, a polytetrafluoroethylene type, a polytetrafluoroethylene type, a polytetrafluoroethylene type, A film made of one or more resins selected from the group consisting of carbonate, polyether sulfone, polysulfone, polyamide, polyimide, polyolefin, polyarylate, polyvinyl alcohol, polyvinyl chloride and polyvinylidene chloride . The optical film may have a thickness of 10 占 퐉 to 100 占 퐉, for example, 10 占 퐉 to 60 占 퐉. In the above range, it can be used for a polarizing plate.

An adhesive layer is formed between the polarizer and the optical film, so that the polarizer and the optical film can be bonded. The adhesive layer may include, but is not limited to, an aqueous adhesive, a pressure sensitive adhesive, and a photocurable adhesive.

The thickness of the polarizing plate may be 30 탆 to 200 탆. In the above range, it can be used for a polarizing plate for a liquid crystal display. The polarizing plate may have a degree of polarization of 99.99% or more, for example, 99.99 to 99.999%, and a light transmittance of 40% or more, for example, 40 to 80% at a wavelength of 380 to 780 nm. In the above-mentioned range, there may be no deterioration of the optical characteristics when the liquid crystal display device is mounted.

Hereinafter, a display device of the present invention will be described.

The display device of the present invention may include the polarizer of the present invention or the polarizer of the present invention. The display device may include a liquid crystal display device, an organic light emitting display device, and the like.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

Specific specifications of the components used in the following examples and comparative examples are as follows.

(1) Polarizer material: polyvinyl alcohol film (VF-PE3000, Kuraray Co., Ltd., thickness: 30 탆)

(2) Optical film: triacetylcellulose film (KC4UYW, Konica, Japan, thickness: 40 m)

Example  One

The polyvinyl alcohol film washed with water was subjected to swelling treatment in a swelling bath of water at 30 캜.

The polyvinyl alcohol film passed through the swelling bath was treated for 30 seconds to 200 seconds in a salt bath at 30 캜 containing an aqueous solution containing 3% by weight of potassium iodide.

The polyvinyl alcohol film passed through the salt-forming bath was passed through a wet crosslinking bath containing 1 to 5% by weight of boric acid in an aqueous solution at 30 캜 to 60 캜. The polyvinyl alcohol film passed through the crosslinking bath was stretched to an aqueous solution containing 50 to 60 占 폚 aqueous solution containing 1 to 5% by weight of boric acid, and stretched so that the total stretching ratio was 6 times

(2-hydroxyethyl) -N- (3'-dodecyloxy-2'-hydroxypropyl) -N, N'-dicyclohexylcarbodiimide -Methylammonium methosulfate (Cytec., CYASTAT (R) 609) and 5% by weight of potassium iodide for 10 to 300 seconds.

The polyvinyl alcohol film passed through the sub-color trough was washed with water and dried to prepare a polarizer (thickness: 12 m).

Polarizers were prepared by adhering optical films on both sides of the prepared polarizer using an adhesive (Z-200, manufactured by Nippon Goshei).

Example  2 to Example  3

The concentration of N, N-bis (2-hydroxyethyl) -N- (3'-dodecyloxy-2'-hydroxypropyl) -N-methylammonium methosulfate and potassium iodide in Example 1 1, a polarizer and a polarizing plate were prepared in the same manner.

Comparative Example  1 and Comparative Example  2

The concentration of N, N-bis (2-hydroxyethyl) -N- (3'-dodecyloxy-2'-hydroxypropyl) -N-methylammonium methosulfate and potassium iodide in Example 1 1, a polarizer and a polarizing plate were prepared in the same manner.

The polarizers and polarizing plates prepared in Examples and Comparative Examples were evaluated for the following properties.

(1) iodide I ^- content of My Iodide I Examples and Comparative Examples ^{polarizer-content} of the pre-treated sample was measured using a Perkin-Elmer's Inductively coupled plasma mass spectrometry (ICP-MS) equipment.

(2) Change in polarization degree: The polarization degree (P ₁ ) of the polarizing plates of Examples and Comparative Examples was measured using a JASCO V7100 at wavelengths of 380 to 780 nm.

After leaving the polarizing plate at 85 캜 for 500 hours, the polarizing degree (P ₂ ) was measured by the same method. The durability was evaluated according to the above formula (1).

(3) Change in color value bc value (? Bc): The color value bc value (bc1) was measured using a JASCO company V7100 at a wavelength of 380 to 780 nm with respect to the polarizing plates of Examples and Comparative Examples. In the V7100, a reference polarizer having a polarization degree of 99.99% or more was mounted, and the color value bc was measured by injecting the absorption axis of the polarizer of the sample polarizer and the absorption axis of the polarizer of the reference polarizer so as to be 90 ° to each other.

After leaving the polarizing plate at 85 캜 for 500 hours, the color value bc (bc2) was measured by the same method. The durability was evaluated according to the above-mentioned formula (2).

(4) Surface resistivity of polarizer: The surface resistivity of the polarizers of Examples and Comparative Examples was measured using a surface high resistance meter of Mitsubishi Chemical Corporation. The polarizer sample was placed on the measuring jig and the surface resistance value was measured.

Example Comparative Example One 2 3 One 2 Compound concentration (% by weight) 0.007 0.05 0.12 0 0 Potassium iodide concentration (% by weight) 5 5 5 5 7 Concentration (wt%) of iodine anion I &lt; ^- &gt; in the polarizer 0.18 0.05 0.04 0.21 0.25 Change in polarization degree (%)     0.17    0.08    0.07     0.2      0.4 Color value bc value variation     1.9      1.2     1.2     2.1      3.2 Polarizer
Surface resistance (Ω / □) Not measurable 8.0x10 ⁹ 5.0x10 ⁹ Not measurable Not measurable

* Not measurable: Indicates that measurement is impossible due to high resistance value.

As shown in Table 1, the polarizer of the present invention exhibited excellent durability because the amount of change in polarization degree after being left at a high temperature was low and the change amount of the color value bc was low.

On the other hand, in Comparative Example 1 and Comparative Example 2 which did not contain the compound of Formula 1, the amount of change in polarization degree and the amount of change in color value were higher than those in Example.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (11)

As a polarizer containing iodine as a dichroic substance and containing iodine anion I < ^{- &} gt ^; in an amount of not more than 0.20 wt%
Wherein the polarizer comprises a complex of a K ⁺ ion and an anion of the following formula 1-1 or 1-2:
&Lt; Formula 1-1 >
[R-SO ₂ -O] ^-
(In the above formula (1-1)
R represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted 7 to 20 carbon atoms An arylalkyl group, or a substituted or unsubstituted C1-C10 alkoxy group),
(1-2)
[R ¹ -SO ₂ -N-SO ₂ -R ² ] ^-
(In the above formula 1-2,
R ¹ and R ² are each independently selected from the group consisting of halogen, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, Or a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms).
delete The polarizer according to claim 1, wherein the polarizer has a surface resistance of 2.0 x ¹⁰ &lt; ¹⁰ &gt;
A method for producing a polyvinyl alcohol film,
Wherein the complementary color treatment comprises treating the colored and drawn polyvinyl alcohol film in a complementary liquid comprising at least one of the following compounds of formula 1 or 2 and potassium iodide:
[Chemical Formula 1]
_{^{M + [R-SO 2 -O}} ] -
(In the above formula 1,
M ⁺ is R ^a R ^b R ^c R ^d N ⁺ , Li ⁺ or Na ⁺ , wherein R ^a , R ^b , R ^c and R ^d are each independently hydrogen, substituted or unsubstituted C 1 to C 10 An alkyl group, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms,
R represents a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted 7 to 20 carbon atoms An arylalkyl group, or a substituted or unsubstituted C1-C10 alkoxy group),
(2)
M ⁺ [R ¹ -SO ₂ -N-SO ₂ -R ² ] ^-
(In the above formula 2,
M ⁺ is R ^a R ^b R ^c R ^d N ⁺ , Li ⁺ or Na ⁺ , wherein R ^a , R ^b , R ^c and R ^d are each independently hydrogen, substituted or unsubstituted C 1 to C 10 An alkyl group or a substituted or unsubstituted C6-C20 aryl group,
R ¹ and R ² are each independently selected from the group consisting of halogen, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 5 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, Or a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms).
[5] The method according to claim 4, wherein at least one of the compounds of Formula 1 or Formula 2 is contained in the complementary color solution in an amount of 0.005 wt% or more and 3 wt% or less, and the potassium iodide is contained in an amount of 0.5 wt% &Lt; / RTI &gt;
5. The method of claim 4, wherein the compound of Formula 1 is selected from the group consisting of N, N-bis (2-hydroxyethyl) -N- (3'-dodecyloxy-2'-hydroxypropyl) &Lt; / RTI &gt;
The positive photosensitive composition as claimed in claim 4, wherein the compound of formula (2) is selected from the group consisting of sodium bis (trifluoromethanesulfonyl) imide, bis (trifluoromethanesulfonyl) imide lithium, bis (fluorosulfonyl) &Lt; / RTI &gt;
A polarizer; And an optical film formed on at least one side of the polarizer,
Wherein the polarizer comprises the polarizer of claim 1 or 3 or a polarizer produced by the method of manufacturing the polarizer of any one of claims 4 to 7.
The polarizing plate according to claim 8, wherein the polarizing plate has a polarization change amount of 3%
<Formula 1>
Change in polarization degree = P ₂ - P ₁ |
(In the above Equation 1,
P ₁ is an initial polarization degree (unit:%) of the polarizing plate,
P ₂ is the degree of polarization (unit:%) after the polarizing plate was left at 85 ° C for 500 hours.
The polarizing plate according to claim 8, wherein the polarizing plate has a color value change amount of 3 or less at a wavelength of 380 to 780 nm,
<Formula 2>
Change in color value = bc ₂ - bc ₁ |
(In the above Equation 2,
bc ₁ is the initial color value of the polarizer,
and bc ₂ is a hue value after the polarizing plate is left at 85 캜 for 500 hours).
A display device comprising the polarizer of claim 8.