TW202112979A - Highly durable dye-based polarizing plate comprising near-infrared absorbing dye - Google Patents

Abstract

A polarizing plate of this invention contains a hydrophilic polymer film containing a near-infrared absorbing dye, and a substrate provided on one or both sides of the film, wherein the substrate has at least one characteristicof the following a) and b):

a) When the hydrophilic polymer film contains a boron compound, after exposing the polarizing plate to an environment of 90% RH and 80℃ for 1000 hours, the mass (boric acid equivalent value) of the boron compound contained in the hydrophilic polymer film is maintained at 20 or more if the value before the exposure is set as 100.

b) The moisture permeability of the substrate based on JIS Z 0208 moisture permeability test in an environment of 90% RH relative humidity and 40℃ is 0 to 1500 g/m² in 24 hours.

Description

High-durability dye-based polarizing plate containing near-infrared absorbing dye

The present invention relates to a polarizing plate. The polarizing plate is a dye-based polarizing plate containing a near-infrared absorbing dye and has high durability in a high temperature and high humidity environment, especially, even if exposed to a strong high temperature and humidity environment. Light also has high durability.

Polarizing plates with light penetration/shielding function are used in display devices such as liquid crystals and liquid crystal displays (LCD) with light switching functions. The application field of the LCD is gradually expanding from small machines such as electronic computers and watches on the market to notebook computers, word processors, liquid crystal projectors, liquid crystal TVs, car navigation systems, and information display devices inside and outside the house. Measuring tools, etc. In addition, polarizing plates can also be applied to lenses with polarizing functions, and are becoming used in sunglasses for improved visibility, or polarized glasses corresponding to 3D TVs in recent years. In addition, the polarizing plate is used not only for display purposes, but also for improving the accuracy of so-called authenticity judging devices, or the signal/noise ratio generated by the interception of reflected light in image sensors such as CCD and CMOS. (S/N ratio) The purpose of the improvement.

General polarizers are formed by forming polyolefins by stretching and oriented polyvinyl alcohol or its derivatives, or by removing hydrochloric acid from polyvinyl chloride films or dehydrating polyvinyl alcohol-based films, and orienting them to form polyolefins. Base materials such as olefin-based films contain iodine or dichroic dyes. Among these, although the iodine-based polarizing element has excellent polarization performance, it has low durability against water and heat, and has a problem in its durability when it is used for a long time in a high temperature and high humidity state. On the other hand, compared to iodine-based polarizers, dye-based polarizers using dichroic dyes have excellent moisture resistance and heat resistance, but generally have insufficient polarization performance.

In recent years, the use of light sources, anti-falsification cameras, sensors, anti-counterfeiting devices, communication equipment, etc. used to identify the actions of touch panels, etc. requires not only the use of polarizers in the visible light region, but also the use in the infrared region. The polarizing plate. In response to this expectation, Patent Document 1 has reported an infrared polarizing plate made by polyalkyleneizing an iodine-based polarizer, and Patent Documents 2 and 3 have reported an infrared polarizing plate using a wire grid. . In addition, Patent Document 4 has reported an infrared polarizer formed by stretching glass containing fine particles, and Patent Documents 5 and 6 have reported an infrared polarizer using cholesteric liquid crystal.

However, the infrared polarizing plate of Patent Document 1 has low durability, especially low heat resistance, wet heat durability, and light resistance, and has not yet reached practical use. The metal wire grid type infrared polarizing plate of Patent Documents 2 and 3 can be processed into a film shape, and at the same time, it is popularized because of its high heat resistance. However, if the infrared polarizing plate has no nanometer-level unevenness on the surface, the optical characteristics cannot be maintained, so the surface cannot be contacted, and there can be no foreign matter or water droplets on the surface, so its use is limited. In addition, the infrared polarizing plate is difficult to perform anti-reflection or anti-glare processing. The infrared polarizing plate described in Patent Document 4 has high durability and high dichroism, so it has been put into practical use. However, since it belongs to glass that is stretched while containing fine particles, it is prone to cracks and brittleness. Moreover, because it does not have the flexibility of the conventional polarizing plate, it also has the problem of difficulty in surface processing or bonding with other substrates. The infrared polarizing plate described in Patent Document 5 and Patent Document 6 uses a technique of circular polarization that has been known since ancient times, but the color changes depending on the viewing angle. Also, basically, because the reflective polarizer is used, stray light is generated, and it is difficult to form absolutely polarized light.

In this way, in an absorption polarizer such as an iodine-based polarizer, there is no infrared polarizer that is formed into a film, has flexibility, and has high durability. This system is due to the fact that the dye that has been developed as a dichroic dye is a dye for the visible light region. In response to such a problem, Patent Document 7 has disclosed a near-infrared polarizing plate by stretching a film containing a dye having absorption in the infrared region. However, the infrared polarizing plate system (near) infrared absorbing dye has poor moisture resistance, and it is not a problem of large heat generation when dealing with (near) infrared absorbing. In recent years, even infrared polarizers are expected to be applied to in-vehicle devices. Therefore, they have high durability in high-temperature and high-humidity environments. In particular, high durability has begun to be required even when infrared rays are irradiated in high-temperature and high-humidity environments. Therefore, it is desired to have an infrared polarizing plate that can meet such requirements and have high durability.

[Prior Technical Literature]

[Patent Literature]

[Patent Document 1] Specification of U.S. Patent Application Publication No. 2,494,686

[Patent Document 2] JP 2016-148871 A

[Patent Document 3] JP 2013-24982 A

[Patent Document 4] JP 2004-86100 A

[Patent Document 5] International Publication No. 2015/87709

[Patent Document 6] Japanese Patent No. 5777463

[Patent Document 7] International Publication No. 2018/88558

[Patent Document 8] Japanese Patent No. 5979728

[Patent Document 9] International Publication No. 2010/073649

[Patent Document 10] Japanese Patent Application Laid-Open No. 59-11385

[Patent Document 11] International Publication 2010/137332

[Patent Document 12] International Publication 2006/112223

[Non-Patent Literature]

[Non-Patent Document 1] Dye Chemistry; Hosoda Toyohiro, 1957, p.621

[Non-Patent Document 2] Development of an analysis method for unreacted boric acid in polarizing plates, Sumitomo Chemical 2012, 2012, pages 27-35

[Non-Patent Document 3] Issued by the Comprehensive Technology Center of Ultraviolet Curing System, Kato Kiyomizu, pages 259-303

Therefore, the object of the present invention is to provide a polarizing plate, which is a dye-based polarizing plate containing a near-infrared absorbing dye and has high durability in a high temperature and high humidity environment, especially, even in a high temperature and high humidity environment. Exposure to strong light also has high durability.

In order to achieve this goal, the inventors have made diligent research and found that polarizing plates with high durability can be obtained by having the following characteristics: , And in the dye-based polarizer set on the substrate of one or both sides of the hydrophilic polymer film, the substrate can maintain the amount of boron compound in the hydrophilic polymer film to a certain extent under the environment of high temperature and high humidity , And/or the moisture permeability is below a certain value in a predetermined moisture permeability test and in a high temperature and high humidity environment.

That is, the present invention relates to the following polarizing plate, and an optical device and a display device provided with the polarizing plate.

[1] A polarizing plate comprising: a polarizing element composed of a hydrophilic polymer film containing a near-infrared absorbing dye, and a substrate provided on one or both sides of the film; and,

The substrate has at least any one of the following characteristics a) and b):

a) When the hydrophilic polymer film contains a boron compound, after the polarizer is exposed to a relative humidity of 90%RH and 80°C for 1000 hours, the time before the exposure is set as 100, the content of the hydrophilic polymer film The quality of the boron compound contained is kept above 20;

b) According to JIS Z 0208 moisture permeability test, the moisture permeability of the substrate in an environment with a relative humidity of 90%RH and 40°C is 0 to 1500g/m ² in 24 hours.

[2] The polarizing plate according to [1], wherein at least one of the aforementioned substrates is a resin-made substrate having the characteristics of b).

[3] The polarizing plate according to [2], wherein a substrate is provided on both sides of the hydrophilic polymer film, and an inorganic substrate or resin-made substrate having the characteristics of b) is provided on the opposite side of the resin-made substrate Substrate.

[4] The polarizing plate according to any one of [1] to [3], wherein the hydrophilic polymer film is selected from the group consisting of polyvinyl alcohol-based resins, amylose-based resins, starch-based resins, and fibers. It is composed of resins in the group consisting of plain resins, polyacrylate resins, and derivatives thereof, and contains a boron compound.

[5] The polarizing plate according to any one of [2] to [4], wherein the resin substrate includes a resin selected from the group consisting of silicon resin, (meth)acrylic resin, cycloolefin resin, and polyester resin. One or more resins in the group consisting of resin and polycarbonate resin.

[6] The polarizing plate according to any one of [2] to [5], wherein the resin substrate includes a film obtained by polymerizing a polymerizable monomer composition, and the polymerizable monomer composition is Contains a (meth)acrylate compound having 3 or more (meth)acrylic groups in the molecule.

[7] The polarizing plate according to [6], wherein the (meth)acrylate compound is selected from the group consisting of neopentyl erythritol skeleton, neopentyl glycol skeleton, trimethylolpropane skeleton, and dicyclopentadiene Any skeleton in the group consisting of alkene skeletons.

[8] The polarizing plate according to [6] or [7], wherein the (meth)acrylate compound is 15 masses in terms of solid content concentration among all monomers in the polymerizable monomer composition %the above.

[9] The polarizing plate according to any one of [3] to [8], wherein the inorganic substrate includes any one of glass, quartz, sapphire, crystal, and spinel.

[10] The polarizing plate according to any one of [2] to [9], wherein the thickness of the resin substrate is 0.5 μm to 10 μm.

[11] The polarizing plate according to any one of [4] to [10], wherein the hydrophilic polymer film contains a polyvinyl alcohol resin or a derivative thereof.

[12] The polarizing plate according to any one of [1] to [11], wherein the near-infrared absorbing dye is an azo compound represented by the following formula (1).

(式(1)中，A¹為可具有取代基之苯基、可具有取代基之萘基或可具有取代基之雜環基，A²、A³及A⁴係分別獨立地為可具有取代基之苯基或可具有取代基之萘基，k係表示0或1之整數；R¹為羥基、碳數1至4之烷氧基或取代或非取代之胺基，m係表示0至5之整數。M係表示氫、金屬離子或銨離子，n係表示1或2之整數；環a及環b之氫原子係可分別獨立地以取代基R¹取代，環a及環b之任一者或兩者的氫原子係以取代基SO₃M取代。)

(In formula (1), A ¹ is an optionally substituted phenyl group, an optionally substituted naphthyl group, or an optionally substituted heterocyclic group, and A ² , A ³ and A ⁴ are each independently an optionally substituted Substituent phenyl or substituted naphthyl, k represents an integer of 0 or 1; R ¹ is a hydroxyl group, an alkoxy group with 1 to 4 carbon atoms or a substituted or unsubstituted amine group, and m represents 0 .M-based integer of 5 to represent hydrogen, a metal ion or an ammonium ion, n-system represents an integer of 1 or 2; a hydrogen atom and ring lines of the loop b can each independently be substituted the substituents R ^1, ring a and ring b The hydrogen atoms of either or both are replaced with the substituent SO ₃ M.)

[13] The polarizing plate according to [12], wherein A ² , A ³ and A ⁴ in the above formula (1) are independently represented by the following formula (2) or formula (3), and A ² At least one of, A ³ and A ⁴ is represented by formula (2).

(式(2)中，R²係表示羥基、碳數1至4之脂肪族烴基、碳數1至4之烷氧基、取代或非取代之胺基或以磺基取代之碳數1至4的烷氧基，m²係表示0至6之整數；M係表示氫、金屬離子或銨離子，n³係表示0至2之整數。)

(In formula (2), R ² represents a hydroxyl group, an aliphatic hydrocarbon group with 1 to 4 carbons, an alkoxy group with 1 to 4 carbons, a substituted or unsubstituted amine group or a sulfo group substituted with 1 to 4 is an alkoxy group, m ² represents an integer from 0 to 6; M represents hydrogen, a metal ion or an ammonium ion, and n ³ represents an integer from 0 to 2.)

(式(3)中，R³及R⁴係分別獨立地表示氫原子、碳數1至4之脂肪族烴基、碳數1至4之烷氧基、以羥基取代之碳數1至4的烷氧基或以磺基取代之碳數1至4的烷氧基。)

(In formula (3), R ³ and R ⁴ each independently represent a hydrogen atom, an aliphatic hydrocarbon group with 1 to 4 carbons, an alkoxy group with 1 to 4 carbons, and a group with 1 to 4 carbons substituted by a hydroxyl group. An alkoxy group or an alkoxy group having 1 to 4 carbons substituted with a sulfo group.)

[14] The polarizing plate according to [12] or [13], wherein the azo compound of the above formula (1) is a compound represented by the following formula (4).

(式(4)中，A¹、A²、A³、A⁴、M、n及k係分別與上述式(1)為相同，又，環a及環b之一者或兩者之氫原子係以取代基SO₃M取代。)

(In formula (4), A ¹ , A ² , A ³ , A ⁴ , M, n, and k are the same as the above formula (1), and the hydrogen of one or both of ring a and ring b The atom is substituted with the substituent SO ₃ M.)

[15] The polarizing plate according to any one of [12] to [14], wherein A ¹ in the above formula (1) or (4) is selected from the group consisting of 1 to 1 carbon atoms substituted with a hydroxyl group and a sulfo group. A naphthyl group substituted with one or more substituents in the group consisting of 4 alkoxy and sulfo groups.

[16] The polarizing plate according to any one of [12] to [14], wherein in the above formula (1) or (4), A ¹ is represented by the following formula (5).

(式(5)中，n⁴係表示1或2之整數。)

(In formula (5), n ⁴ represents an integer of 1 or 2.)

[17] The polarizing plate according to any one of [12] to [14], wherein A ¹ in the above formula (1) or (4) is substituted with at least one selected from a nitro group and a sulfo group Group substituted phenyl.

[18] The polarizing plate according to any one of [12] to [14], wherein the heterocyclic group which may have a substituent in ^{A 1 of the above formula (1) or (4) is selected from (6)} ) To (8) in the group consisting of the groups shown in (8).

(式(6)至(8)中之X係分別獨立地為鹵素基、硝基、羥基、碳數1至4之脂肪族烴基、碳數1至4之烷氧基、以磺基取代之碳數1至4之脂肪族烴基、以羥基取代之碳數1至4之脂肪族烴基、以羧基取代之碳數1至4之脂肪族烴基、以磺基取代之碳數1至4之烷氧基、以羥基取代之碳數1至4之烷氧基、或以羧基取代之碳數1至4之烷氧基，q¹係表示0至4之整數，q²係表示0至6之整數；M係表示氫、金屬離子、或銨離子，n¹及n²係分別獨立地表示0至3之整數；各式中＊係表示與偶氮鍵結之接合位置。)

(X in formulas (6) to (8) are each independently a halogen group, a nitro group, a hydroxyl group, an aliphatic hydrocarbon group with a carbon number of 1 to 4, an alkoxy group with a carbon number of 1 to 4, and a sulfo group substituted Aliphatic hydrocarbon groups with 1 to 4 carbons, aliphatic hydrocarbon groups with 1 to 4 carbons substituted with hydroxyl groups, aliphatic hydrocarbons with 1 to 4 carbons substituted with carboxyl groups, alkanes with 1 to 4 carbons substituted with sulfo groups An oxy group, an alkoxy group with a carbon number of 1 to 4 substituted by a hydroxyl group, or an alkoxy group with a carbon number of 1 to 4 substituted by a carboxyl group, q ¹ represents an integer from 0 to 4, and q ² represents a range from 0 to 6 Integer; M represents hydrogen, metal ion, or ammonium ion, n ¹ and n ² each independently represent an integer from 0 to 3; in each formula, * represents the bonding position of the azo bond.)

[19] The polarizing plate according to any one of [1] to [18], wherein at least 700 to 1500 nm has the absorbance of the axis showing the highest transmittance for polarized light, and the absorbance for polarized light The light shows the lowest transmittance axis in the wavelength range where the ratio of absorbance to absorbance is 5 or more.

[20] The polarizing plate according to any one of [12] to [19], which further contains one or more kinds of organic dyes other than the azo compound represented by the above formula (1).

[21] The polarizing plate as described in [20], which displays a neutral gray.

[22] An optical device comprising the polarizing plate according to any one of [1] to [21].

[23] A display device comprising the polarizing plate described in any one of [1] to [21] or the optical device described in [22].

The above-mentioned polarizing plate and device contain near-infrared absorbing dyes, and have high durability in high temperature and high humidity environments. In particular, they have high durability even when exposed to strong light, especially infrared rays, in high temperature and high humidity environments. Sex.

Hereinafter, the present invention will be described in detail through its implementation modes. However, the present invention is not limited by the following implementation types.

The polarizing plate produced by the embodiment of the present invention is characterized by a dye-based polarizing plate including a hydrophilic polymer film containing a near-infrared absorbing dye and a substrate, and the hydrophilic polymer film has a specific The characteristic substrate has high durability in a high temperature and high humidity environment.

Hereinafter, each component will be described.

(Near infrared absorbing dye)

Generally speaking, the so-called infrared region (also sometimes referred to as infrared wavelength region or infrared region wavelength region) refers to the wavelength region from 700 nm to 3000 nm, and the so-called near infrared region refers to the wavelength region from 700 nm to 1500 nm, but the implementation of the present invention The resulting polarizing plate contains near-infrared absorbing dyes and has a polarizing function in the near-infrared region. Therefore, the polarizing plate obtained by the embodiment of the present invention has a polarization function in the wavelength region of 700nm to 1500nm, but preferably has a polarization function in the wavelength region of 700nm to 1300nm, and more preferably in the wavelength region of 750nm to 1200nm The area plays a polarizing function. As suck If the anisotropic dichroic ratio is 5 or more, it can be used as a sensor, but it is preferably 10 or more, more preferably 20 or more, still more preferably 30 or more, particularly preferably 40 or more. Specifically, if the monomer transmittance is set to 30%, when the dichroic ratio is 5, the degree of polarization is 88.2% and about 90%, and when the dichroic ratio is 10, the degree of polarization is 98.3. % And about 99% polarization.

The near-infrared absorbing dyes used in the embodiment of the present invention include, for example, phthalocyanines, naphthalocyanines, metal complexes, boron complexes, cyanines, squaraine, and diiminium. Dyestuffs based on dyes, diphenylamine/triphenylamine, quinone, and azo dyes. Generally speaking, these dyes extend the existing π-conjugated system to make the absorption wavelength longer, and display a variety of absorption wavelengths through their structure. In addition, many of them take the form of hydrophobic dyes or pigments, but some are used as hydrophilic dyes by making them water-soluble. A preferred embodiment of the present invention uses an azo-based near-infrared absorbing dye as the near-infrared absorbing dye. In addition, in this specification, the near-infrared absorbing dye may only be abbreviated and described as a dye.

The above-mentioned near-infrared absorbing dye system may be in a free form or in the form of a salt. Therefore, the near-infrared absorbing dye in the specification of this case includes both forms. Examples of the salt system include alkali metal salts such as lithium salt, sodium salt, and potassium salt; and organic salts such as ammonium salt and alkylamine salt, and sodium salt is preferred.

General azo dyes absorb light in the visible light region, and water-soluble inks are the main purpose. However, there are already commercially available near-infrared absorbing dyes that can absorb to the near-infrared region by widening the absorption band, and these can also be used. For example, Patent Document 8 describes the use of CIacid Black 2 (manufactured by Orient Chemical Industry Co., Ltd.) and CIDirect Black 19 (manufactured by ALDRICH Industrial Co., Ltd.) for the purpose of producing black ink, but these can also be used. dye. In addition, these azo dyes may form complexes with metals, and these complexes may also be used. Examples of the complex system include compounds of the following formula (9).

式中，Mz係表示中心金屬，金屬種係例示鈷、鎳等。又，式中，Az及Bz係分別獨立地表示苯基或萘基等之芳香族環。由如此之錯合物所構成的染料之具體例係例示專利文獻10記載之近紅外線線吸收劑。專利文獻10之內容係藉由參照而摘入於本案中。

In the formula, Mz represents the central metal, and the metal species exemplifies cobalt, nickel, and the like. In addition, in the formula, Az and Bz each independently represent an aromatic ring such as a phenyl group or a naphthyl group. Specific examples of dyes composed of such complexes are the near-infrared ray absorbers described in Patent Document 10. The content of Patent Document 10 is extracted in this case by reference.

The near-infrared absorbing dye is preferably a water-soluble azo compound, and particularly preferably an azo compound represented by the following formula (1).

In the above formula (1), A ¹ is an optionally substituted phenyl group, an optionally substituted naphthyl group, or an optionally substituted heterocyclic group, and A ² , A ³ , and A ⁴ are each independently an optional The substituted phenyl group or the substituted naphthyl group, k represents an integer of 0 or 1. R ¹ is a hydrogen atom, a hydroxyl group, an alkoxy group having a carbon number of 1 to 4, or a substituted or unsubstituted amine group, and m is an integer of 0 to 5. M represents hydrogen, metal ion, or ammonium ion, and n represents an integer of 1 or 2. The hydrogen atoms of the ring a and the ring b may be independently substituted with the substituent R ¹ , and the hydrogen atoms of either or both of the ring a and the ring b are substituted with the substituent SO ₃ M.

A ¹ in the "group of the phenyl may have a substituent", "naphthyl group may have a substituent group of the" and "may have a substituent group the heterocyclic group" in the "substituent group" is not particularly limited, but include for example, An aliphatic hydrocarbon group with 1 to 4 carbons which may have a substituent, an alkoxy group with 1 to 4 carbons which may have a substituent, an alkoxy group with 1 to 4 carbons which may be substituted with a sulfo group, and those which may have a substituent Aryloxy group, hydroxyl group, sulfo group, carboxyl group, nitro group, halogen atom, substituted or unsubstituted amine group, amide group, etc.

The above-mentioned "aliphatic hydrocarbon groups with 1 to 4 carbons which may have substituents" include, for example, linear aliphatic hydrocarbon groups such as methyl, ethyl, n-propyl, n-butyl, isopropyl, and second Branched chain aliphatic hydrocarbon groups such as butyl and tertiary butyl groups, cyclic aliphatic hydrocarbon groups such as cyclobutyl groups, etc., and these substituents may be, for example, hydroxyl, sulfo, carboxyl, substituted or unsubstituted amine groups ( (Described later), or amide group substitution.

The above-mentioned "optionally substituted alkoxy group having 1 to 4 carbons" includes, for example, methoxy, ethoxy, n-propoxy, n-butoxy, isopropoxy, and second butoxy , Tert-butoxy, cyclobutoxy, etc. These substituents may be substituted with, for example, a hydroxyl group, a sulfo group, a carboxyl group, a substituted or unsubstituted amine group (described later), or an amido group.

The above-mentioned "alkoxy group having 1 to 4 carbon atoms substituted with a sulfo group" includes, for example, sulfomethoxy, sulfoethoxy, 3-sulfopropoxy, 4-sulfobutoxy, 3-sulfobutane Oxy etc.

The above-mentioned "aryloxy group which may have a substituent" system includes, for example, 5-membered or 6-membered monocyclic aryloxy group or 11-membered to 14-membered condensed bicyclic aryloxy group. More specifically, benzene may be mentioned. Oxy, naphthoxy, etc. The "substituent" in the "aryloxy group which may have a substituent" is not particularly limited, and examples thereof include aliphatic hydrocarbon groups having 1 to 4 carbons which may have the above-mentioned substituents.

The above-mentioned "halogen atom" includes, for example, a chlorine atom and a bromine atom.

_{The above-mentioned "substituted or unsubstituted amino group" includes, for example, unsubstituted amino groups; mono C 1-4} alkyl groups such as methyl amino groups, ethyl amino groups, n-propyl amino groups, n-butyl amino groups, etc. Monoarylamino groups such as amine groups, monophenylamino groups, mononaphthylamino groups (5-membered or 6-membered monocyclic arylamine groups or 11-member or even 14-membered condensed bicyclic arylamine groups), Monosubstituted amino groups such as acylamino groups (preferably of the formula: R-CO-NH- acylamino groups (wherein R is an aliphatic hydrocarbon group with 1 to 4 carbon atoms)); and, dimethyl Amino, diethylamino, N-ethyl-N-methylamino and other two C _1-4 alkylamino groups, diphenylamino groups and other diarylamino groups (selected from 5 members or 6-membered monocyclic aryl group and 11-membered to 14-membered condensed bicyclic aryl group (amino group substituted with 2 aryl groups), C _1-4 alkane with N-ethyl-N-phenylamino group, etc. And disubstituted amino groups such as 5-membered or 6-membered monocyclic aryl groups or 11 to 14-membered condensed bicyclic aryl substituted amino groups.

A ¹ in the "group of a phenyl substituent" of the "substituent groups" more preferably selected from the group consisting of alkyl substituents at the sulfo group, a carboxyl group, a hydroxyl group, a sulfo group of 1 to 4 carbon atoms, alkoxy, of 1 to 4 carbon atoms The aliphatic hydrocarbon group, the alkoxy group with carbon number of 1 to 4, the amino group substituted with halogen atom, nitro group, unsubstituted amine group, the aliphatic hydrocarbon group with carbon number of 1 to 4, the formula: R-CO-NH- Amino (in the formula, R is an aliphatic hydrocarbon group with 1 to 4 carbons), and formula: an amino (in the formula, R is an aliphatic hydrocarbon with 1 to 4 carbons, each independently of hydrogen or carbon One or more substituents in the group consisting of aliphatic hydrocarbon groups (1 to 4). The "substituent" is more preferably a sulfo group, a carboxyl group, a hydroxyl group, a chlorine atom, a bromine atom, a nitro group, an unsubstituted amino group, a 3-sulfopropoxy group, a 4-sulfobutoxy group, or a 3-sulfobutoxy group base.

When the phenyl group has two or more substituents, at least one of the substituents is an alkoxy group having 1 to 4 carbons substituted with a sulfo group, a nitro group, a carboxyl group, or a sulfo group, preferably others Substituents are sulfo groups, nitro groups, aliphatic hydrocarbon groups with 1 to 4 carbons, alkoxy groups with 1 to 4 carbons, alkoxy groups with 1 to 4 carbons substituted with sulfo groups, carboxyl groups, halogen atoms , Nitro group, amine group, aliphatic hydrocarbon substituted amine group with 1 to 4 carbon atoms, or aliphatic hydrocarbon substituted amine group with 1 to 4 carbon atoms. Other substituents are preferably sulfo, methyl, ethyl, methoxy, ethoxy, carboxy, hydroxy, 2-sulfoethoxy, 3-sulfopropoxy, 4-sulfobutoxy, chlorine Atom, nitro group, or amino group, more preferably sulfo, carboxy, nitro, methyl, methoxy, 2-sulfoethoxy, 3-sulfon Propoxy or 4-sulfobutoxy, particularly preferably sulfo, carboxy, nitro, methyl, methoxy, hydroxy, 3-sulfopropoxy, or 4-sulfobutoxy.

The position of the "substituent" of the "substitutable phenyl group" in A ¹ is not particularly limited, but it is preferably only at the 2-position, only at the 4-position, at the 2-position and the 6-position, at the 2-position and at the 2-position. 4 digits, or 3 and 5 digits, especially good ones are only 2 digits, only 4 digits, 2 and 4 digits, or 3 and 5 digits. In addition, only the 2-position and only the 4-position system means that there is only one substituent other than the hydrogen atom at the 2-position or the 4-position.

When ^{the combination of the preferable substituent of the "phenyl which may have a substituent" and its position in A 1} is such that an azo bond is used as the 1-position, examples include those having a sulfo group at the 2-position and a nitro group at the 4-position. A phenyl group or a phenyl group each having a carboxyl group at the 3-position and 5-position.

The "substituent" of the "substitutable naphthyl group" in A ¹ is preferably selected from the group consisting of a hydroxyl group, a sulfo group substituted with an alkoxy group having 1 to 4 carbon atoms, and a sulfo group The group is more preferably a sulfo group, 3-sulfopropoxy group, 4-sulfobutoxy group or hydroxyl group. When the substitution position of the azo group is set to the 1-position, it is rotated counterclockwise, and it is more preferably a naphthyl group substituted with a hydroxyl group at the 8-position, and particularly preferably any position is substituted with a sulfo group in the following formula (5) Shown by naphthyl.

(式(5)中，n⁴係表示1或2之整數，以1為較佳。)

(In formula (5), n ⁴ represents an integer of 1 or 2, and 1 is preferred.)

基(piperazinyl)、喹啉基、苯并咪唑基、萘并咪唑基、苯并噻唑基、 萘并噻二唑基、苯并噻二唑基等，以可具有取代基之苯并噻二唑基或萘并噻二唑基為較佳。 The "heterocyclic group which may have substituents" in A ¹ includes, for example, thiazolyl, oxazolyl, imidazolyl, thienyl, furyl, pyrrolyl, thiadiazolyl, and pyrazole which may have substituents. Pyridyl, pyridyl, hexahydropyridine

Group (piperazinyl), quinolinyl, benzimidazolyl, naphthimidazolyl, benzothiazolyl, naphththiadiazolyl, benzothiadiazolyl, etc., and optionally substituted benzothiadiazole Nyl or naphththiadiazolyl is preferred.

The "substituent" in the above-mentioned "substitutable heterocyclic group" is not particularly limited, but preferred examples include sulfo group, carboxyl group, halogen atom, nitro group, hydroxyl group, and aliphatic hydrocarbon group with 1 to 4 carbon atoms. , Alkoxy groups with 1 to 4 carbons, aliphatic hydrocarbon groups with 1 to 4 carbons substituted with sulfo groups, aliphatic hydrocarbon groups with 1 to 4 carbons substituted with hydroxyl groups, and aliphatic hydrocarbon groups with 1 to 4 carbons substituted with carboxyl groups Aliphatic hydrocarbon group, alkoxy group with 1 to 4 carbons substituted with sulfo group, alkoxy group with 1 to 4 carbons substituted with hydroxyl group, and alkoxy group with 1 to 4 carbons substituted with carboxyl group, more preferred It is a hydroxyl group, a carboxyl group or a sulfo group.

Such heterocyclic groups are particularly preferably selected from the group consisting of groups represented by the following formulas (6) to (8).

(式(6)至(8)中之X係分別獨立地為鹵素基、硝基、羥基、羧基、碳數1至4之脂肪族烴基、碳數1至4之烷氧基、以磺基取代之碳數1至4之脂肪族烴基、以羥基取代之碳數1至4之脂肪族烴基、以羧基取代之碳數1至4之脂肪族烴基、以磺基取代之碳數1至4之烷氧基、以羥基取代之碳數1至4之烷氧基或以羧基取代之碳數1至4的烷氧基，較佳係磺基、羧基或羥基，q¹係表示0至4之整數，較佳係表示0或1，q²係表示0至6之整數，較佳係表示0或1。M係表示氫、金屬離子或銨離子，n¹及n²係分別獨立地表示0至3之整數，較佳係表示0或1。各式中＊係表示與偶氮鍵結之接合位置。)

(X in formulas (6) to (8) are each independently a halogen group, a nitro group, a hydroxyl group, a carboxyl group, an aliphatic hydrocarbon group with 1 to 4 carbons, an alkoxy group with 1 to 4 carbons, and a sulfo group. Substituted aliphatic hydrocarbon groups with 1 to 4 carbons, aliphatic hydrocarbon groups with 1 to 4 carbons substituted with hydroxy groups, aliphatic hydrocarbon groups with 1 to 4 carbons substituted with carboxyl groups, and 1 to 4 carbons substituted with sulfo groups The alkoxy group, the alkoxy group with 1 to 4 carbons substituted by a hydroxyl group, or the alkoxy group with 1 to 4 carbons substituted with a carboxyl group, preferably a sulfo group, a carboxyl group or a hydroxyl group, q ¹ represents 0 to 4 Integer preferably represents 0 or 1, q ² represents an integer from 0 to 6, preferably represents 0 or 1. M represents hydrogen, metal ion or ammonium ion, n ¹ and n ² represent independently An integer from 0 to 3, preferably represents 0 or 1. In each formula, * represents the bonding position of the azo bond.)

^{A 2} , A ³ and A ⁴ in the above formula (1) are each independently an optionally substituted phenyl group or an optionally substituted naphthyl group. The "substituent group" in "substitutable phenyl group" or "substitutable naphthyl group" is not particularly limited, and it can be compared with "substitutable phenyl group" and "substitutable group" in A ¹ above. The substituents exemplified by the "substituent" in the "substituent naphthyl group" and the "substitutable heterocyclic group" are the same.

^{A 2} , A ³ , and A ⁴ in the above formula (1) are each independently represented by the following formula (2) or formula (3). In order to obtain a wide-band polarizing element, A ² , A ^{At least one of 3} and A ⁴ is represented by formula (2).

In the above formula (2), R ² represents a hydroxyl group, an aliphatic hydrocarbon group with 1 to 4 carbons, an alkoxy group with 1 to 4 carbons, a substituted or unsubstituted amine group, or a sulfo group substituted with a carbon number of 1 to 4 is an alkoxy group, m ² represents an integer from 0 to 6. M represents hydrogen, metal ion or ammonium ion, and n ³ represents an integer from 0 to 2. Aliphatic hydrocarbon groups with 1 to 4 carbons, alkoxy groups with 1 to 4 carbons, substituted or unsubstituted amine groups, alkoxy groups with 1 to 4 carbons substituted with sulfo groups, and M series can be respectively combined with the formula (1) is the same.

In the above formula (2), m ² is preferably 0 to 4, more preferably 0 to 2, and particularly preferably 0 or 1. In addition, when m ² is 1 or more, R ² is preferably a hydroxyl group. For n ³ , 0 or 1 is preferred, and 1 is even more preferred. In formula (1), if the substitution position of ^{R 2 is set to the 1 position with the bonding position of the A 1} side to the azo group, the 2 position, the 3 position, the 5 position or the 8 position are preferred. Specifically, it is preferable that either the 2-position or the 3-position is substituted by a methoxy group, and the 3-position is more preferable that it is substituted by a methoxy group. In addition, the 5-position or 8-position is preferably substituted by a hydroxyl group. In the above formula (1), when A ³ or A ⁴ has the structure shown in the above formula (2), it is a wide-band region and exhibits a polarization function with a high degree of polarization, so it is preferable. Specifically, k=0 At this time, it is preferable that A ³ has the structure of formula (2), and when k=1, it is preferable that A ⁴ has the structure of formula (2).

In the above formula (3), R ³ and R ⁴ each independently represent a hydrogen atom, an aliphatic hydrocarbon group with 1 to 4 carbons, an alkoxy group with 1 to 4 carbons, and a carbon 1 to 4 substituted with a hydroxyl group. An alkoxy group or an alkoxy group having 1 to 4 carbons substituted with a sulfo group. Aliphatic hydrocarbon groups with 1 to 4 carbons, alkoxy groups with 1 to 4 carbons, alkoxy groups with 1 to 4 carbons substituted with hydroxyl groups, and alkoxy groups with 1 to 4 carbons substituted with sulfo groups They are the same as formula (1) respectively. In the above formula (1), when A ³ or A ⁴ has the structure shown in formula (3), and R ³ or R ⁴ are each independently a hydrogen atom or an alkoxy group with 1 to 4 carbon atoms, they are preferably respectively When independently being a methoxy group or an ethoxy group, it is particularly ^{preferable that when R 3} and R ⁴ are a methoxy group, it is a wide band and exhibits a polarization function with a high degree of polarization. Specifically, when k=0, it is preferable that A ³ has the structure of formula (3), and R ³ and R ⁴ are methoxy groups, and when k=1, it is preferable that A ⁴ has the formula (3) , And R ³ and R ⁴ are methoxy groups.

^{R 1} in the above formula (1) is a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, or a substituted or unsubstituted amine group. R ¹ is preferably a hydrogen atom or a hydroxyl group, more preferably a hydroxyl group. When ^{the substitution position of R 1} is based on the hydroxyl group of ring a as the 1-position, the 5-position is preferred.

M in the above formula (1) represents hydrogen, metal ion or ammonium ion. Examples of the metal ion system include alkali metal ions such as lithium ion, sodium ion, and potassium ion, and alkaline earth metal ions such as calcium ion and magnesium ion. The ammonium ion system includes, for example, ammonium ion, methylammonium ion, dimethylammonium ion, triethylammonium ion, tetraethylammonium ion, tetra-n-propylammonium ion, tetra-n-butylammonium ion, and triethylammonium ion. Ethanol ammonium ion and so on. More specifically, for example, when M is hydrogen, it means sulfonic acid (-SO ₃ H), when M is sodium ion, it means sodium sulfonate (-SO ₃ Na), and when M is ammonium ion, it means ammonium sulfonate. (-SO ₃ NH ₄ ).

The hydrogen atom system of the ring a and the ring b in the above formula (1) may be substituted with the above substituent (R ¹ ) and/or the above substituent (-SO ₃ M).

It is preferable that either or both of ring a and ring b in the above formula (1) are substituted with a sulfo group. Furthermore, it is also preferable that ring b is substituted with a hydroxyl group. Among them, when the azo bonding site of ring a is used as the 1-position, it rotates counterclockwise, the 2-position is substituted with a hydroxyl group and the 3-position and 7-position are substituted with a sulfo group, and the 4-position is substituted with a sulfo group. A ring structure in which the 2-position is substituted with a hydroxyl group and the 4-position is substituted with a sulfo group, or a ring structure in which the 7-position is substituted with a sulfo group is particularly preferred.

The azo compound represented by the above formula (1) is particularly preferably a compound represented by the following formula (4).

In the above formula (4), A ¹ to A ⁴ , M, n, k, ring a, and ring b are the same as the above formula (1), respectively. Among the azo compounds represented by the above formula (1), the compound represented by the above formula (4) has a wider band and exhibits a near-infrared region polarization function with a high degree of polarization, so it is preferable.

Specific examples of the azo compound represented by the above formula (1) are listed below. In addition, the sulfo group, carboxyl group, and hydroxyl group in the formula are expressed in the form of free acid, but the azo compound represented by the above formula (1) also includes the salts of the compounds listed below.

The azo compound represented by the above formula (1) or a salt thereof can be produced, for example, by performing diazolation and coupling in accordance with the usual production method of azo dyes as described in Non-Patent Document 1.

As an example of a specific manufacturing method, the manufacturing method of the compound in which k=0 in the above-mentioned formula (1) is described as follows.

The amino naphthalenes represented by the following formula (A) are diazotized, and the amino naphthalenes represented by the following formula (B) or anilines are coupled once to obtain the following formula (C) The single azoamine-based compound. The monoazoamine compound (C) is diazolated, and the amino naphthalenes or anilines represented by the following formula (D) are coupled to each other to obtain the double compound represented by the following formula (E) Azoamine-based compounds. The bisazoamine compound (E) is diazolated, and the azo compound of the above formula (1) is obtained by three-time coupling with the naphthol of the following formula (F).

In the above manufacturing method, the diazolation step is preferably based on the sequential method of mixing nitrite such as sodium nitrite in an aqueous solution or suspension of an inorganic acid such as hydrochloric acid, sulfuric acid, etc., or a diazonium Nitrite is added to a neutral or weakly alkaline aqueous solution of the base component in advance, and this is performed by the reverse order method of mixing this with an inorganic acid. The appropriate temperature for diazotization is -10 to 40°C. In addition, the coupling with aminonaphthalenes or anilines is preferably performed by mixing acidic aqueous solutions of hydrochloric acid, acetic acid, etc., with each of the above-mentioned diazonium-based liquids, and performing acidic conditions of pH 2 to 7 at a temperature of -10 to 40°C.

The azo compound of formula (C) and formula (E) obtained by coupling is directly filtered, or precipitated and filtered by acid precipitation or salting out, and then taken out, or directly as a solution or suspension Go to the following steps. The diazonium salt is poorly soluble and can be filtered when it becomes a suspension to form an extruded filter cake and used in the following coupling step.

The third coupling reaction of the diazonium compound of the bisazoamine compound of the above formula (E) with the naphthol represented by the above formula (F) is preferably at a temperature of -10 to 40°C from pH 7 to 10 Neutrality is carried out under alkaline conditions. After the reaction is terminated, the obtained azo compound or salt of the formula (1) is preferably precipitated by salting out and filtered to be taken out. In addition, when purification is necessary, it is only necessary to repeat salting out or use an organic solvent to precipitate from water. The organic solvent used for the purification includes, for example, water-soluble organic solvents such as alcohols such as methanol and ethanol, and ketones such as acetone.

The near-infrared absorbing dye represented by formula (1) or its salt can be used as a dye for polarizing elements. It has a high polarizing function in the near-infrared region. By combining with other constituent elements described later, it can provide A high-performance dye-based polarizing plate in the near-infrared region of moisture/heat resistance/light resistance.

(Other organic dyes)

In the embodiment of the present invention, in addition to the near-infrared absorbing dye, the polarizing element may contain other organic dyes that have polarizing properties in the visible light region. In this way, for example, it is possible to realize not only the infrared light region but also the dye-based polarizing plate capable of controlling neutral gray up to the visible light region. Here, "neutral gray" means that when two polarizing elements are overlapped with their orientation directions orthogonal to each other, the light leaks at a specific wavelength in the visible light region and the near-infrared region, or in the full wavelength ( Color leakage) is less. In this specification, other dyes with polarization properties in the visible light region are sometimes simply referred to as other organic dyes.

Other organic dyes are not particularly limited, but they are preferably dyes that have dichroism in a wavelength region different from the absorption wavelength region of the azo compound or its salt represented by formula (1), and its dichroism High dyes. Such organic dyes include, for example, CIDirect Yellow 12, CIDirect Yellow 28, CIDirect Yellow 44, CIDirect Orange 26, CIDirect Orange 39, CIDirect Orange 71, CIDirect Orange 107, CIDirect Red 2, CI Direct Red 31, CIDirect Red 79, CIDirect Red 81, CIDirect Red 247, CIDirect Blue 69, CIDirect Blue 78, CIDirect Blue 247, CIDirect Green 80, and CIDirect Green 59 are representative examples. These organic dyes can be included in the polarizing element as a free acid, or as an alkali metal salt (such as Na salt, K salt, Li salt), ammonium salt, or amine salt.

Polarizers containing near-infrared absorbing dyes and other organic dyes. The purpose of the polarizer is a neutral gray polarizer, a color polarizer for liquid crystal projectors, and other color polarizers of various colors. board. Therefore, the types of other organic dyes contained are different. The blending ratio of other organic dyes is not particularly limited, but when the mass of the near-infrared absorbing dye represented by formula (1) is taken as 100, the total of one or more other organic dyes is preferably 0.1-10.

In the case of a neutral gray polarizer with a polarization function in the near-infrared region, it is better to adjust the near-infrared absorbing dye and others that absorb light in the infrared region so that the color leakage in the visible light region of the obtained polarizer is reduced The types of organic dyes and their blending ratios.

(Hydrophilic polymer film and polarizing element)

In the embodiment of the present invention, the polarizing element is composed of a hydrophilic polymer film, and the hydrophilic polymer film contains the above-mentioned near-infrared absorbing dye and optionally other organic dyes (hereinafter, there are Sometimes referred to as near-infrared absorbing dyes, etc.) and oriented.

"Hydrophilic polymer membrane" refers to a membrane that has a high affinity for water. Generally, it refers to a membrane that absorbs water and swells when it is immersed in or in contact with water. The preferred embodiment uses this characteristic to make it Contains near-infrared absorbing dyes, etc., or makes them oriented. The hydrophilic polymer film is not particularly limited, but examples thereof include films composed of polyvinyl alcohol resin, amylose resin, starch resin, cellulose resin, polyacrylate resin, or derivatives thereof. In the specification of the present case, the so-called "derivative" means that the above-mentioned resin makes the unique basic skeleton common, but at the point of other structures, some modified resins are added. Derivatives of the above-mentioned resins such as polyvinyl alcohol include resins modified with olefins such as ethylene and propylene, or unsaturated carboxylic acids such as crotonic acid, acrylic acid, methacrylic acid, and maleic acid.

From the viewpoint of the adsorption and orientation properties of near-infrared absorbing dyes, etc., a film composed of polyvinyl alcohol resin or its derivatives is the most preferred.

Under severe conditions such as high temperature and high humidity, in order to maintain the oriented state of near-infrared absorbing dyes and the like and maintain the polarization characteristics, it is preferable to be composed of a resin with a cross-linked structure of a hydrophilic polymer film. because Therefore, in a preferred embodiment of the present invention, the polarizing element is composed of a hydrophilic polymer film formed by cross-linking the above resin with a boron compound such as boric acid or borax. In addition, the combination of a polarizing element having such a cross-linked structure and a substrate having the characteristics of a) described later is a particularly preferred embodiment of the present invention.

The thickness of the hydrophilic polymer film is not limited, but is usually 10 to 100 μm, preferably about 25 to 80 μm.

In the embodiment of the present invention, the polarizing element is a hydrophilic polymer film containing near-infrared absorbing dyes, etc., by extending the hydrophilic polymer film, the hydrophilic polymer and the hydrophilic polymer The dye contained is oriented to express the anisotropy of absorption in the near-infrared region and the arbitrarily selected visible light region (so-called dichroism).

Hydrophilic polymer films containing near-infrared absorbing dyes, etc. For example, after swelling a hydrophilic polymer film such as polyvinyl alcohol-based films in warm water, it may contain 0.001 to 0.001 to 1000 parts by weight of water, such as near-infrared absorbing dyes. It is produced by immersing a film formed by swelling it in an aqueous solution of 10 parts by mass. The aqueous solution containing near-infrared absorbing dyes and the like may contain dyeing auxiliary agents as needed, for example, Glauber's salt may be contained in a concentration of about 0.1 to 10% by mass. The time for immersing the film in the dye bath is, for example, about 1 to 10 minutes. The dyeing temperature is preferably about 30 to 80°C.

A hydrophilic polymer film containing a near-infrared absorbing dye or the like can also be produced by preliminarily containing a near-infrared absorbing dye in a hydrophilic polymer, and forming a hydrophilic polymer containing the near-infrared absorbing dye into a film. For example, polyvinyl alcohol is dissolved in an aqueous solution of 8 to 12% by mass in water, and the solid content of the aqueous solution contains near-infrared absorbing dyes at a concentration of 0.01 to 10% by mass, and the aqueous solution is cast into a film to be used as a solvent. The water evaporates, whereby a hydrophilic polymer film containing near-infrared absorbing dyes and the like can be obtained.

In order to align the near-infrared absorbing dyes in the hydrophilic polymer film to obtain a polarizing element, the film containing near-infrared absorbing dyes etc. is usually stretched. For example, it can be any well-known method such as wet method and dry method. Methods. When a hydrophilic polymer film containing near-infrared absorbing dyes and the like is stretched by a wet method, for example, it is placed in a tank of a liquid containing a boron compound such as boric acid or borax and stretched in the uniaxial direction up to 2 to 9 times, and then, It was dried, thereby obtaining a polarizing element.

The treatment with boron compound is generally performed for the purpose of increasing the light transmittance and polarization of the dye-based polarizing element. However, as described later, in the hydrophilic polymer film treated in this way, near-infrared absorbing dyes, etc. can be used at high temperatures. In a high-humidity environment, a boron compound such as boric acid or borax is used to maintain crosslinking. Therefore, the content of the boron compound can be used as an index to maintain the orientation of the near-infrared absorbing dye together with the hydrophilic polymer film.

The conditions for treatment with boron compounds such as boric acid and borax vary depending on the type of hydrophilic polymer film used or the type of near-infrared absorbing dye used, but for example, in the case of a film made of polyvinyl alcohol, The concentration of the boron compound (in terms of boric acid) in the aqueous solution is set to 0.1 to 10% by mass, preferably 0.5 to 7% by mass, and particularly preferably 1 to 5% by mass. The stretching treatment is, for example, in the temperature range of 30 to 80°C, preferably 40 to 75°C, for example, immersing for 0.5 to 10 minutes to extend in the uniaxial direction to 2 to 9 times. If the pH of the treatment step is 5 to 9, it can become a wide band of the wavelength range with the polarization function of the polarizing element using near-infrared absorbing dyes, etc., but more preferably 6.5 to 8.5, particularly preferably 6.0 to 8.0 It is a better type.

The method of adjusting the pH of the aqueous solution during the treatment, especially the aqueous solution containing boric acid, to 6 to 9, preferably by adding alkaline substances such as sodium hydroxide, potassium hydroxide, borax and the like for treatment. In addition, when borax is used, boric acid and borax can be used in combination. If necessary, an aqueous solution containing a cationic polymer compound may be combined and subjected to a fixation treatment. The above-mentioned extension treatment can be carried out in one stage or in multiple stages of two or more stages.

The extension of the hydrophilic polymer membrane can be carried out before dyeing as the case may be. At this time, the orientation of the water-soluble dye is carried out in the stage of dyeing. The treatment with the boron compound can be carried out after the above-mentioned extension step. In this case, the extension step may be carried out in a liquid (for example, water) that does not contain a boron compound.

The performance of the polarizing element can be adjusted by the content of the near-infrared absorbing dye, the dichroism of the near-infrared absorbing dye, and the stretching ratio during stretching.

The above-mentioned stretching treatment may be a dry stretching method. Dry stretching means applying heat to the film and stretching the film when it becomes soft by the heat. In the case of the dry stretching method, air (air) or nitrogen can be used as the stretching heating medium for stretching. The temperature is preferably the glass transition temperature or melting point of the hydrophilic polymer film, and the processability is considered according to the resin constituting the film. The types of spores are extended at room temperature to 200°C. In addition, the humidity is preferably processed in any environment of 0 to 95% RH. The heating method includes, for example, an inter-roll zone stretching method, a roll heating stretching method, a pressure stretching method, an infrared ray heating stretching method, etc. However, heat is conducted to the film, and if stretching is possible, it is not limited to these. The stretch magnification is preferably 2 to 9 times, but it may be adjusted by considering the stretchable magnification of each resin and the stretch magnification that can be used to align the dye. The extension process can be processed in one stage or in multiple stages of two or more stages.

(Substrate)

The polarizing plate includes the above-mentioned polarizing element and a substrate laminated on the polarizing element. In the embodiment of the present invention, the polarizing plate is characterized by having a substrate with the following a) or b), preferably a) and b).

a) When the hydrophilic polymer film contains a boron compound, after exposing the polarizer to an environment with a relative humidity of 90%RH and 80°C for 1000 hours, use 100% before the exposure to maintain the content of the hydrophilic polymer film. The mass of boron compound is more than 20%.

b) The moisture permeability of the substrate in an environment with a relative humidity of 90%RH and 40°C based on the JIS Z 0208 moisture permeability test is 0 to 1500 g/m ² in 24 hours.

With the substrate with the above-mentioned characteristics, the polarizing plate can have high durability even in a high temperature and high humidity environment, especially when exposed to strong light in a high temperature and high humidity environment.

That is, a polarizing plate that satisfies the characteristics of a) maintains the content of the boron compound contained in the hydrophilic polymer film at a high level even if exposed to a high temperature and high humidity environment, but such characteristics mean The polarizing element has a high degree of cross-linking structure and maintains the orientation state of the near-infrared absorbing dye, etc. obtained by stretching. The polarizing plate with such characteristics can suppress the anisotropy and decomposition deterioration of near-infrared absorbing dyes even in a high-temperature and high-humidity environment, and can maintain high transmittance and high degree of polarization. However, as disclosed in Non-Patent Document 2, the hydrophilic polymer film exemplified by polyvinyl alcohol does not cross-link all the boron compounds in a polarizing element containing a dichroic pigment, but will then be cross-linked. The boric acid is separated from the water and so on. In the environment of high temperature and high humidity, the boron compound cross-links are gradually separated from the hydrophilic polymer film and diffused. The diffusion system is not limited to the hydrophilic polymer film, but will move toward the adhesive layer or transparent layer laminated on the polarizing element. The protective layer moves. However, the movement of the boron compound is less, and the higher the retention rate of the boron compound in the hydrophilic polymer film, the more the cross-linking can be maintained, even if it is exposed to a high temperature and high humidity environment, it can be maintained to a high degree. Therefore, it is important to prevent the diffusion of the boron compound from the hydrophilic polymer film and the migration to the substrate, but the system must have a low affinity between the boron compound and the substrate. Its affinity can be measured by the solubility or the amount of movement of the chemical substance, but from our research results, we know that the retention rate of the boron compound in the polarizing element shows that the affinity between the boron compound and the substrate is a very good indicator of inhibiting the movement of the boron compound. effective. Considering the above circumstances, in the mass of the boron compound contained in the hydrophilic polymer film, 100% is used before the exposure, and 20% or more of the substrate is used as a substrate that also contains near-infrared absorbing dyes under high temperature and high humidity environments. It is an index of obtaining high durability among other polarizing elements, and finally reached the invention.

A polarizing plate that satisfies the characteristics of b) means that even if it is exposed to a high-temperature and high-humidity environment, the water that passes through the substrate and reaches the polarizing element is small. Therefore, it is difficult for the polarizing element to cause the relaxation of orientation due to moisture. The orientation state obtained by stretching is maintained, and the cohesive force of molecules in the hydrophilic polymer film can be maintained at a high state. In addition, when a boron compound is included, it indirectly indicates that it is difficult to detach the crosslink from the hydrophilic polymer film, and it is difficult to cause diffusion or movement to the substrate. Even in the high temperature and high humidity environment, the polarizing plate system with such characteristics can suppress the anisotropy and decomposition deterioration of the near-infrared absorbing dye, and can maintain high transmittance and high polarization.

For the characteristics of the above a), when the amount of boron compound before the above exposure is taken as 100%, it is better to keep 35% or more of the boron compound after the above exposure, more preferably to maintain 50% or more, and to maintain 60% or more. Even better.

The characteristic of b) is the relative humidity 90%RH, 40℃ environment, the moisture permeability of the substrate after 24 hours, preferably 0 to 1100g/m ² , more preferably 0 to 900g/ m ² , even more preferably, can represent 0 to 800 g/m ² .

The substrate can be provided on one side of the polarizing element to give any of the above characteristics, but it is preferable to arrange the same or different substrates on both sides of the polarizing element, so that even when exposed from either side of the polarizing element In a high-temperature and high-humidity environment, it can also inhibit the influence of moisture or cross-link breakage and move the boron compound, or it can impart both characteristics.

When the polarizing element is provided with a substrate, the substrate may be directly connected to the polarizing element to be laminated, but the polarizing element may be provided with a substrate via another layer such as an adhesive layer. Therefore, in the specification of this case, when the substrate is provided on "single or both sides of the polarizing element", it includes two situations: the case where the substrate is directly connected to the polarizing element, and the other layer is interposed. When the polarizing element is provided with a substrate.

As for other layers, a film used as an optical film can generally be provided between the substrate and the polarizing element. The optical film system that can be set between the substrate and the polarizing element, for example, can be exemplified generally used in the polarizing plate The three cellulose acetate film, cycloolefin film, acrylic film or film used as a phase difference plate, etc. The phase difference plate may be a phase difference plate composed of a polymer or a phase difference plate composed of liquid crystal, and it is not limited. The retardation plate generally uses 1/4λ, 1/2λ, etc. for the wavelength to be controlled, but any retardation plate can also be used.

The substrates satisfying the above-mentioned characteristics a) and/or b) may be inorganic substrates and organic resin substrates.

An inorganic substrate that can satisfy the above-mentioned characteristics a) and/or b) is, for example, a substrate made of transparent glass, quartz, sapphire, crystal, or spinel. In the case of the description of this case, “transparency” means that the polarizing plate has a wavelength band with polarization characteristics, for example, in the range of 380 to 1500 nm, the transmittance has a transmittance of more than 20%. In the polarizing plate that requires transparency, it is better to have a transmittance of 50% or more, it is even better to have a transmittance of 80% or more, and it is particularly preferable to have a transmittance of 90% or more. In this regard, a substrate made of quartz, sapphire, or crystal has high transparency and is a preferable inorganic substrate. In addition, in terms of high thermal conductivity, that is, high heat dissipation, these inorganic substrates are preferable, and a substrate made of sapphire or crystal is more preferable. If a polarizing element oriented in a hydrophilic polymer film such as a near-infrared absorbing dye absorbs high-brightness light in the infrared region, the polarizing element dissipates heat, so the so-called high heat dissipation is to improve the durability of the polarizer. , Has important meaning.

In terms of transparency, glass is slightly inferior, but it has the advantages of low cost and easy manufacture, and it can also be used in combination with other substrates. The glass series includes soda glass, borosilicate glass, alkali-free glass, etc., but it is not particularly limited.

In substrates that do not require transparency, other inorganic substrates can also be used. For example, by using aluminum, silver, iron, silicon, copper, etc., to make the surface reflective (glossy) and scattering reflectivity, it is also possible to obtain a polarized light reflection element for the purpose of optically polarized light reflection.

When the substrate is provided on both sides of the polarizing element, it is preferable to use at least one substrate as an inorganic substrate from the viewpoint of imparting high durability even in a high-temperature and high-humidity environment. For example, it can be made of glass, quartz, A substrate made of sapphire or crystal. From the same point of view, inorganic substrates can also be provided on both sides of the polarizing element. At this time, the substrates may be the same inorganic substrates or different inorganic substrates. Also, from the viewpoint of transparency and heat dissipation, it is particularly preferable to sandwich both sides of the polarizing element with a substrate made of quartz, sapphire, or crystal. In addition, when a substrate is provided on one side of the polarizing element and the polarizing plate is attached to an optical device or a display device, if the other side is attached to an inorganic substrate such as glass of the device, the inorganic substrate of the device can essentially serve as a polarizing plate The function of the substrate.

When the inorganic substrate is laminated on the polarizing element via the adhesive layer or the adhesive layer, the adhesive or the adhesive is applied to the inorganic substrate to form the adhesive layer or the adhesive layer. The adhesive or the adhesive system is not particularly limited as long as it can be adhered. For the adhesive system, for example, ultraviolet curable adhesives, thermosetting adhesives, silicon-based adhesives, and the like can be used. In addition, the adhesive is not particularly limited. For example, acrylic (co)polymer resins, silicone adhesives, etc. obtained by polymerizing a monomer composition containing at least acrylic alkyl esters can be used. However, it is not limited to these. In addition, it may be a combination of a hardening type adhesive and an adhesive. For an adhesive system that combines a hardening type adhesive and an adhesive, for example, the adhesive compound composition described in Patent Document 9 can be suitably used, and the content of Patent Document 9 is incorporated in the specification of this application by reference. The subsequent layer system may be a resin substrate described later.

The resin substrate system that can satisfy the above characteristics a) or b) can be selected from silicone resins, acrylic resins, olefin resins, cycloolefin resins, polyester resins, vinylidene chloride resins, and polycarbonate resins. One type or two or more types of substrates. In particular, a substrate made of silicone resin, acrylic resin, cycloolefin resin, polyester resin, or polycarbonate resin is preferable. The substrate can be in the shape of a film (thin and flexible).

The silicone resin is preferably a silicone resin polymerized with (meth)acrylic acid group-containing organossesquioxanes described in Patent Document 11 (International Publication 2010/137332) as the main component, and can be used to make The resulting film serves as a substrate. By reference, the content of Patent Document 11 is extracted in the specification of this case.

The acrylic resin is based on, for example, the description of Example 1 of Patent Document 12 (International Publication 2006/112223), preferably an acrylic resin, and a film obtained by forming such a film can be used as a substrate. By reference, the content of Patent Document 12 is extracted from the specification of this case.

The film system composed of a cycloolefin-based resin exemplifies ZEONOR manufactured by Japan's Zeon Corporation or ARTON manufactured by JSR Corporation as preferred films, and these films can be used as substrates.

The polyester resin is preferably a polyethylene terephthalate resin or a polyethylene naphthalate resin, and a film composed of these resins is preferably an SRF film manufactured by Toyobo Co., Ltd., for example.

As the vinylidene chloride resin, for example, SARAN resin manufactured by Asahi Kasei Co., Ltd. is preferable, and a film obtained by forming such a film can be used as a substrate.

The polycarbonate resin is preferably PUREACE manufactured by Teijin Corporation or R film manufactured by KANEKA Corporation, and these can be used as a substrate.

There are no particular restrictions on the adhesive or adhesive system when the polymer substrate is laminated on the polarizing element with the adhesive layer or the adhesive layer interposed therebetween, as long as it can be adhered. Type adhesive, silicon-based adhesive, etc. In addition, the adhesive system can be, for example, acrylic (co)polymer resin obtained by polymerizing a monomer composition containing at least (meth)acrylic acid alkyl ester, or a silicon adhesive, but it is not limited to these. In addition, a hardening type adhesive and an adhesive may be combined. The adhesive compound system which combines a hardening type adhesive agent and an adhesive agent can use the adhesive compounding composition described in the above-mentioned patent document 9 suitably. The subsequent layer may be a layer composed of a cured product obtained by polymerizing a polymerizable compound described later.

In a preferred embodiment of the present invention, as a resin substrate that satisfies the above-mentioned characteristics a) or b), for example, a resin substrate having a glycidyl group, (meth)acryloyl group, isocyanate group, etc. A substrate composed of a specific resin obtained by polymerizing a compound with a polymerizable substituent.

More specifically, a substrate composed of a cured product of a composition containing a polymerizable monomer described in Non-Patent Document 3 can be exemplified. By reference, the content of Non-Patent Document 3 is extracted in this specification. A suitable system includes a substrate composed of a cured product obtained by polymerizing a polymerizable monomer composition containing a compound having a (meth)acryloyl group and a polymerization initiator. In a preferred embodiment of the present invention, the polymerizable monomer composition includes a compound having two or more (meth)acrylic groups. In this embodiment, the polymerizable monomer composition is in all monomers, and the compound containing two or more (meth)acrylic groups is preferably 30% by mass or more, more preferably 50% by mass or more , More preferably more than 70% by mass.

In a more preferable embodiment of the present invention, the polymerizable monomer composition includes a compound having three or more (meth)acrylic groups. In this embodiment, among all the monomers of the polymerizable monomer composition system, the monomer having 3 or more (meth)acrylic groups is contained at least 30%, and more preferably at least 50% is contained. More than 70% is particularly good. The polymerizable monomer composition system composed of such a monomer can obtain a substrate composed of a hard resin with a higher crosslinking density.

In order for the substrate to satisfy the above characteristics a) and/or b), among the above-mentioned compounds having a (meth)acryloyl group, it is preferable to have a neopentylerythritol skeleton, a neopentyl glycol skeleton, a trimethylolpropane skeleton, And a compound of at least one type or more of the structure of the dicyclopentadiene skeleton. In a preferred embodiment, the (meth)acrylate compound having such a skeleton is preferably contained in a solid content of 15% by mass or more in all monomers, and more preferably 30% by mass or more. It is even more preferable to contain 50% by mass or more, and it is particularly preferable to contain 70% or more.

Examples of compounds having such a structure are shown in Table 1 together with the moisture permeability.

[Table 1]

The method for evaluating the moisture permeability above is formed by coating semi-suned kraft paper (taken from TOTSUYA ECHO Co., Ltd.) to anchor coating of polyvinyl alcohol with a solid content of 5% to a thickness of 1μm. The monomer composition of the resin substrate is cured to form a resin substrate, or the resin substrate or the inorganic substrate formed is pasted. The composition system comprising a compound having a (meth)acryloyl group as the polymerizable monomer described in Table 1 above will have 10 parts by weight of the compound having a (meth)acryloyl group, 5 parts by weight of toluene, and 1-hydroxy ring 0.6 parts by weight of hexyl phenyl ketone (IRGACURE 184 manufactured by BASF Corporation) was mixed and used as a composition. The composition was coated on the semi-suned kraft paper anchored and coated with polyvinyl alcohol so that the solid resin content after solvent volatilization became 5 μm in thickness.

After placing the finished sample under the condition of b), the moisture permeability of semi-suned kraft paper can be confirmed according to JIS Z 0208, and the moisture permeability of the substrate can be evaluated.

Products with a neopentylerythritol skeleton can include KAYARAD PET-30, KAYARAD PET-40, KAYARAD DPHA, etc., products with a neopentyl glycol skeleton can include KAYARAD NPGDA, etc., products with a trimethylolpropane skeleton Examples include KAYARAD TMPTA and the like, and products having a dicyclopentadiene skeleton include KAYARAD R-684.

Among such (meth)acrylate compounds, in terms of lower moisture permeability and excellent moisture and heat resistance, one having a neopentyl erythritol skeleton, a neopentyl glycol skeleton, or a trimethylolpropane skeleton The (meth)acrylate compound is more preferable, and the (meth)acrylate compound having a neopentylerythritol skeleton is particularly preferable.

In the case of the composition in which the above-mentioned resin composition is polymerized by ultraviolet rays, the resin composition may contain an ultraviolet polymerization initiator. Examples of the ultraviolet polymerization initiator system include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1 (IRGACURE 907 manufactured by BASF), 1-hydroxycyclohexyl Phenyl ketone (IRGACURE 184 manufactured by BASF), 4-(2-hydroxyethoxy)-phenyl(2-hydroxy-2-propyl) ketone (IRGACURE 2959 manufactured by BASF), 1-(4-decane Alkylphenyl)-2-hydroxy-2-methylpropane-1-one (MERCK DAROCURE 953), 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropane-1-one (DAROCURE 1116 manufactured by MERCK), 2-hydroxy-2-methyl-1-phenyl Propane-1-one (IRGACURE 1173 manufactured by BASF), diethoxy acetobenzene and other acetobenzene compounds, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin iso Benzoin-based compounds such as propyl ether, benzoin isobutyl ether, 2,2-dimethoxy-2-phenylacetonitrile (IRGACURE 651 manufactured by BASF), benzoin benzoic acid , Benzoyl methyl benzoate, 4-phenylbenzophenone, hydroxybenzophenone, 4-benzyl-4'-methyl diphenyl sulfide, 3,3'-dimethyl 4-methoxybenzophenone (KAYACURE MBP manufactured by Nippon Kayaku Pharmaceutical Co., Ltd.) and other benzophenone compounds, thioxanthone (Thioxanthone), 2-chlorothioxanthone (KAYACURE CTX manufactured by Nippon Kayaku Pharmaceutical Co., Ltd.) ), 2-methylthioxanthone, 2,4-dimethylthioxanthone (KAYACURE RTX manufactured by Nippon Kayaku Co., Ltd.), isopropylthioxanthone, 2,4-dichlorothioxanthone ( KAYACURE CTX manufactured by Nippon Kayaku Pharmaceutical Co., Ltd., 2,4-diethyl thioxanthone (KAYACURE DETX manufactured by Nippon Kayaku Pharmaceutical Co., Ltd.), 2,4-diisopropyl thioxanthone (KAYACURE DITX manufactured by Nippon Kayaku Pharmaceutical Co., Ltd.), etc. Lucanthone-based compounds, etc. More preferred systems include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1 (IRGACURE 907 manufactured by BASF), 1-hydroxycyclohexyl phenyl ketone (BASF IRGACURE 184 manufactured by the company), and 2,2-Dimethoxy-2-phenylacetonitrile (IRGACURE 651 manufactured by BASF). These photopolymerization initiators may be of one kind or may be used by mixing a plurality of them at any mixing ratio.

When the aforementioned benzophenone-based compound or thioxanthone-based compound is contained as an ultraviolet polymerization initiator, an auxiliary agent may be used in combination in order to promote the photopolymerization reaction. Such auxiliary agents include, for example, triethanolamine, methyldiethanolamine, triisopropanolamine, n-butylamine, N-methyldiethanolamine, diethylaminoethyl methacrylate, Michler Ketone, 4,4'-diethylaminophenol, ethyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate (n-butoxy), 4-dimethylamine Amine compounds such as isoamyl benzoate.

The addition amount of the above-mentioned photopolymerization initiator and auxiliary agent is preferably used in a range that does not cause a decrease in the polarization performance, and the amount is relative to the polymerizable substitution such as (meth)acryloyl group in the polymerizable composition. 100 parts by weight of the base compound, preferably 0.5 parts by weight or more and 12 parts by weight or less, more preferably 2 parts by weight or more and 10 parts by weight or less. In addition, the amount of the auxiliary agent may be about 0.5 to 2 times relative to the photopolymerization initiator.

When the polymerizable monomer composition contains a thermally polymerizable monomer, it may contain a polymerization initiator, a crosslinking agent, and/or an initiator. As the crosslinking agent, various known crosslinking agents such as isocyanate, boron, and titanate can be used. The addition amount can be 0.1 part by weight or more and 20 parts by weight or less in 100 parts by weight of the polymerizable monomer composition, and more preferably can be about 1 part by weight or more and 10 parts by weight or less in 100 parts by weight of the composition.

The method of forming a resin substrate is, for example, using the above polymerizable monomer composition as a stock solution, or diluting with a solvent as necessary, polarizing element or a film laminated on the polarizing element, or directly or via an adhesive layer after film formation It can be applied to a film that can be transferred to a polarizing element, and then the solvent can be removed as necessary by heating or the like, and by heating or irradiating ultraviolet rays, a substrate as the polymerizable resin cured layer of the present invention can be obtained. In addition, a cellulose triacetate film or the like can be used as the film system laminated on the polarizing element.

The solvent of the aforementioned monomer composition is preferably one that has excellent solubility of the monomers in the composition and wettability to the substrate, and does not cause a decrease in the smoothness of the substrate surface, for example, water; toluene, Aromatic hydrocarbons such as xylene; ethers such as anisole, dioxane, and tetrahydrofuran; methyl isobutyl ketone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 2-pentanone, 3-pentanone, 2- Ketones such as hexanone, 3-hexanone, 2-heptanone, 3-heptanone, 4-heptanone, 2,6-dimethyl-4-heptanone, etc.; n-butanol, 2-butanol, ring Alcohols such as hexanone and isopropanol; cellosolves such as methyl cellosolve and methyl cellosolve acetate; ethyl acetate, butyl acetate, methyl lactate, propylene glycol monomethyl ether acetate , Propylene glycol ethyl ether acetate, methoxy ethyl acetate, ethoxy ethyl acetate Esters such as esters; but not limited to dimethyl sulfene, acetonitrile, and N,N-dimethyl acetonitrile. Preferably it is toluene, cyclopentanone, or ethyl acetate. In addition, the solvent system may be a single or a mixture. The concentration of the resin composition varies depending on solvent solubility, wettability to the substrate, thickness after coating, etc., but is preferably 5 to 95% by weight, more preferably about 10 to 80% by weight.

In addition, when the wettability to the substrate is insufficient, or when the smoothness of the formed substrate surface is low, in order to improve these problems, various leveling agents may be added to the resin composition. As the leveling agent, various leveling agents such as silicon-based, fluorine-based, polyether-based, acrylic copolymer-based, and titanate-based, can be used. The addition amount can be 0.0001 parts by weight or more and 10 parts by weight in 100 parts by weight of the polymerizable monomer composition, and more preferably 0.1 parts by weight or more and about 5 parts by weight in 100 parts by weight of the monomer composition. .

When the monomer composition forming the film is cured, when the adhesion of the polarizing element of the substrate or the film laminated on the polarizing element is poor, various crosslinking agents may be added to the monomer composition in order to improve these problems. As the type of crosslinking agent, various compounds such as isocyanate-based, boron-based, and titanate-based compounds can be used. The addition amount can be 0.0001 part by weight or more and 20 parts by weight or less in 100 parts by weight of the polymerizable monomer composition, more preferably 0.1 part by weight or more and 10 parts by weight or less in 100 parts by weight of the composition.

The method of forming a resin substrate is a method of directly coating a polarizing element; a method of providing a resin substrate on a film used for laminating cellulose triacetate or the like; or, a layer of polymerizable monomer composition is formed on After another film is transferred or laminated to provide a substrate on the polarizing element; the method of providing an adhesive layer and then laminating a resin substrate on it can also make the polarizing plate more efficient and simple . The method of coating the polymerizable monomer composition is not particularly limited, and examples include spin coating, wire bar coating, gravure coating, microgravure coating, calender coating, and spray coating. Methods such as coating method, meniscus coating method, etc.

The above-mentioned resin substrate is preferably heated or irradiated with ultraviolet rays to fully polymerize the monomers, with very few unreacted components. The degree is that the unreacted monomer (for example, acrylate compound) in 100 parts by weight of the cured resin composition can be 0 parts by weight or more and 5 parts by weight or less, and more preferably, it can be 0 parts by weight or more and 3 parts by weight or less. More preferably, it may be 0 part by weight or more and 1 part by weight or less. The method of obtaining such a layer includes, for example, a method of optimizing the thickness of the layer of the resin composition after coating; a method of optimizing the type or amount of the photopolymerization initiator added; sufficient heating or ultraviolet irradiation The method; the method of changing the environment during ultraviolet irradiation to harden it in an inert gas such as nitrogen. In terms of a simple method, it is convenient to optimize the thickness of the resin layer at the point that only the resin concentration or the resin coating amount can be optimized.

The thickness of the resin substrate is preferably 0.5 μm or even 10 μm, more preferably 1 μm or even 8 μm, and even more preferably 2 μm to 6 μm. If it is thicker than 10 μm, the remaining unreacted monomer may increase, and the wet heat durability may become insufficient, and the polarizing plate may undergo a red change in the dry heat durability test. On the other hand, if it is thinner than 0.5 μm, the wet heat durability is likely to become insufficient. The amount of ultraviolet irradiation varies depending on the type of acrylate compound, the type and amount of the photopolymerization initiator, and the film thickness, but it can be, for example, about 100 to 1500 mJ/cm ² .

In addition, the above-mentioned resin substrate is preferably treated with an alkaline solution and is also transparent. Specifically, after treatment at 40°C for 10 minutes or longer with an aqueous alkali solution having a pH of 11 or higher, the non-cloudy system becomes an index. The standard is that cellulose triacetate is coated with an ultraviolet curable monomer composition to a thickness of 5μm, and the film with a cured layer is treated with an aqueous solution of pH 11 at 40°C for more than 10 minutes, and the light in the wavelength of 550nm penetrates The transmittance can still be over 85%, preferably over 90%. On the other hand, by treating the resin substrate with an aqueous alkali solution to make the surface of the resin substrate hydrophilic, it is also preferable because the adhesion to a hydrophilic polymer film such as a polyvinyl alcohol film is improved. As far as the resin substrate at that time is an indicator of hydrophilicity, For use: the contact angle when dripping 10μL of water is 60° or less, more preferably 50° or less, and even more preferably 40° or less. When attaching a polarizing element, after treatment with an alkaline aqueous solution, neutralization treatment with water or an acidic aqueous solution, after which, a drying treatment is the preferred formula.

When it is desired to obtain a polarizing plate that satisfies both of the aforementioned conditions a) and b), it is preferable to have a multilayer structure having two or more layers of a substrate composed of a cured product of a polymerizable monomer composition.

When obtaining a polarizing plate containing the above-mentioned resin substrate, the resin substrate can be laminated directly on the polarizing element. However, for example, the composition of a polarizing plate containing a general cellulose triacetate film (hereinafter, abbreviated as TAC), such as "TAC/ Adhesive layer (or adhesive layer)/polarizing element/adhesive layer (or adhesive layer)/TAC" between any one of the layers of the polarizing plate shown in "Tac" or is provided with more than one layer of the above-mentioned resin substrate on the surface. Improve durability. Specifically, it can be on the surface of the TAC that is not facing the adhesive layer (or adhesive layer), between the TAC and the adhesive layer (or adhesive layer), or between the adhesive layer (or adhesive layer) and the polarizing element; One can have more than one layer to improve durability. In order to improve durability, it is effective to provide a resin substrate on the side of the exposed surface after bonding to the display device. Specifically, after bonding the polarizing plate to the display device, the TAC on the surface side of the exposed surface is bonded to the TAC(F) and the display device, and then the adhesive layer (or adhesive layer) on the surface side of the exposed surface is bonded ) Is set as the adhesive layer (F), the composition of the polarizing plate is "TAC(F)/adhesive layer (F)/polarizing element/adhesive layer (or adhesive layer)/TAC/adhesive layer/display device", but in In this structure, a substrate made of a cured polymer resin is preferably provided on the surface of the TAC (F), between the TAC (F) and the adhesive layer (F), or between the adhesive layer (F) and the polarizing element. . In addition, in order to prevent the improvement of adhesion or the movement of unreacted monomers in the resin substrate, an anchor coating layer may be provided between the polarizing element and the resin substrate.

The above-mentioned polarizing element may be laminated with a transparent film or layer other than the above-mentioned substrate as a protective layer on one side or on both sides thereof. The TAC exemplified by the structure of the above-mentioned general polarizing plate may also be one of its protective layers. The transparent protective layer can be formed by coating with a polymer to form a layer or a laminated film. The transparent polymer or film forming the transparent protective layer is preferably a transparent polymer or film with high mechanical strength and good thermal stability. Regarding the substance used as a transparent protective layer, for example, cellulose acetate resin such as cellulose triacetate or diacetyl cellulose or its film, the main chain or side chain is an imine group and / Or amide resin or polymer or its film, etc. Can be provided with liquid crystal resin or its film. The polarizing plate can be made by arranging more than one layer of the same or different resin or film on one side or on both sides. The thickness of the protective layer or the film used as the protective layer is not particularly limited, but may be 0.5 to 200 μm, preferably 10 to 100 μm.

Adhesives that can be used to bond the polarizing element and the protective layer include polyvinyl alcohol-based adhesives, urethane emulsion-based adhesives, acrylic-based adhesives, and those composed of polyols and isocyanates. Adhesives and the like are not particularly limited.

<Surface treatment layer>

A transparent surface treatment layer may be further provided on the surface of the above-mentioned polarizing plate. Examples of the surface treatment layer include acrylic, urethane, or polysiloxane hard coat layers, or general anti-reflection layers (AR layers) and anti-glare layers (AG layers). In addition, in order to further improve the penetration rate of the veneer, it is better to provide an AR layer on the protective layer. The AR layer can be formed by, for example, vapor deposition or sputtering treatment of silicon dioxide, titanium oxide, etc., and can be formed by thin coating of a fluorine-based material. The AG layer is a coating layer containing particles made of silicon dioxide or polymer as a material, and can also be formed to exhibit anti-glare properties by internal scattering or scattering that forms unevenness. The polarizing plate of this case can also be attached with a phase difference plate on the surface to be used as a circular polarizing plate or an elliptical polarizing plate.

<Purpose of Polarizing Plate>

The application of the polarizing plate obtained by the present invention includes, for example, liquid crystal projectors, electronic computers, watches, notebook computers, word processors, liquid crystal televisions, car navigation systems, and indoor and outdoor measuring devices. Or monitors, etc., and lenses or glasses, devices for authenticity determination, CCD and CMOS image sensors, etc. The dye-based polarizing element system has high polarization performance even in the near-infrared region, and is also excellent in durability. Therefore, it is particularly suitable for various liquid crystal display applications, liquid crystal projectors, automotive applications, and outdoor displays (such as display applications or wearable applications such as industrial meters), which must have high polarization performance and durability. Reliable safety devices, etc.

[Example]

Hereinafter, the present invention will be described in more detail with examples, but these are exemplary and do not limit the present inventors in any way. In addition, the "%" and "parts" described below are quality standards unless otherwise stated. Moreover, in each structural formula of the compound used in each Example and Comparative Example, the acidic functional group, such as a sulfonic group, is described in the form of a free acid, but it is not limited to this.

[Synthesis Example 1]

(step 1)

After adding 31.9 parts of 4-amino-5-hydroxy-2,7-naphthalene disulfonic acid to 200 parts of water, using 25% sodium hydroxide to adjust the pH from 6 to 8 while dissolving, the 4-toluenesulfonic acid 19.1 parts of acetonitrile were kept at pH 10.5 to 11.0, dropped in, and stirred to complete the reaction. Thereafter, after salting out with sodium chloride, filtration was performed to obtain 142 parts of a wet cake of the compound represented by the following formula (101).

(Step 2)

142 parts of the wet cake of the compound represented by the formula (101) obtained was added to 300 parts of water, stirred to suspend it, 25% sodium hydroxide was used to make the pH 9.0, and 40% sodium hydroxide was added to it. 15.5 parts of sodium nitrate aqueous solution. The obtained suspension was dropped into a mixed liquid of 100 parts of water and 37.5 parts of 35% hydrochloric acid to prepare a diazonium base liquid. On the other hand, 20.1 parts of 8-aminonaphthalene-2-sulfonic acid was added to 200 parts of water, and it was dissolved while adjusting the pH to 6 to 8 using a 25% aqueous sodium hydroxide solution. In this solution, the previously obtained diazonium-based solution is maintained at pH 4.5 to 6.0 with 35% hydrochloric acid as needed, and dropped, and stirred to complete the coupling reaction. Then, after salting out with sodium chloride, filtration was performed and 148 parts of wet cakes of the monoazo compound represented by formula (102) were obtained.

(Step 3)

Add 148 parts of the resulting wet cake of the bisazo compound represented by formula (102) to 300 parts of water, stir to suspend it, use 25% sodium hydroxide to make the pH 9.0, and then add it to it Add 10.9 parts of 40% sodium nitrite aqueous solution. The obtained suspension was dropped into a mixed liquid of 100 parts of water and 26.3 parts of 35% hydrochloric acid to prepare a diazonium base liquid. On the other hand, 14.0 parts of 8-aminonaphthalene-2-sulfonic acid was added to 200 parts of water, and a 25% sodium hydroxide aqueous solution was used to dissolve while adjusting the pH to 6 to 8. In this solution, the diazonium-based solution of the above formula (102) is maintained at pH 4.5 to 6.0 with 35% hydrochloric acid as needed, and dropped, followed by stirring to complete the coupling reaction. Thereafter, after salting out with sodium chloride, the crystal was filtered to obtain 138 parts of a wet cake of the disazo compound represented by the following formula (103).

Add 138 parts of the obtained wet cake of the monoazo compound represented by formula (103) to 300 parts of water, stir to suspend it, use 25% sodium hydroxide to make the pH 9.0, and then add it to it Add 7.6 parts of 40% sodium nitrite aqueous solution. The obtained suspension was dropped into a mixed liquid of 100 parts of water and 18.4 parts of 35% hydrochloric acid to prepare a diazonium base liquid. On the other hand, 14.1 parts of 1,5-dihydroxynaphthalene-2,6-disulfonic acid was added to 150 parts of water, and a 25% sodium hydroxide aqueous solution was used to dissolve while adjusting the pH to 6 to 8. In this liquid, the diazonium base liquid of the above formula (103) is maintained at a pH of 6.5 to 8.0 and dropped, followed by stirring to complete the coupling reaction. Thereafter, after salting out with sodium chloride, the crystallization was filtered and dried to obtain 74.6 parts of a wet cake of the parazo compound represented by the following formula (104).

74.6 parts of the obtained wet cake of the parazo compound represented by the above formula (104) was added to 300 parts of water, stirred and suspended, and the pH was maintained at 10.0 to 10.5 with 25% sodium hydroxide. Stir at 50 to 55°C for 2 days. Then, after salting out with sodium chloride, filtration and drying were performed to obtain 9.0 parts of the water-soluble dichroic dye shown in the following [Compound Example 1-5].

[Synthesis Example 2]

(step 1)

Add 21.8 parts of 2-amino-5-nitrobenzenesulfonic acid to 500 parts of water, adjust the pH to 6 to 8 with 25% sodium hydroxide, and then dissolve it, then add 35% hydrochloric acid to make the pH 0.2 . 17.3 parts of 40% sodium nitrite aqueous solution was added to the obtained liquid to prepare a diazonium base liquid. On the other hand, 22.3 parts of 8-aminonaphthalene-2-sulfonic acid was added to 200 parts of water, and a 25% sodium hydroxide aqueous solution was used to dissolve while adjusting the pH to 6 to 8. In this liquid, the previously prepared diazonium base liquid was kept at pH 4.5 to 6.0 and dropped, and stirred to complete the coupling reaction. Then, after salting out with sodium chloride, filtration was performed and 241 parts of wet cakes of the monoazo compound represented by the following formula (105) were obtained.

(Step 2)

241 parts of the obtained wet cake of the monoazo compound represented by the above formula (105) was added to 300 parts of water, stirred and suspended, and 25% sodium hydroxide was used to make the aforementioned suspension pH 9.0, and then add 34.5 parts of 40% sodium nitrite aqueous solution to it. The obtained suspension was dropped into a mixed liquid of 200 parts of water and 50 parts of 35% hydrochloric acid to prepare a diazonium base liquid. On the other hand, 22.3 parts of 8-aminonaphthalene-2-sulfonic acid were added In 200 parts of water, a 25% sodium hydroxide aqueous solution was used to dissolve while adjusting the pH to 6 to 8. In this liquid, the diazonium base liquid of the above formula (105) is kept at pH 4.5 to 6.0 and dropped, and the coupling reaction is terminated by stirring. Then, after salting out with sodium chloride, filtration was performed and 342 parts of wet cakes of the disazo compound represented by the following formula (106) were obtained.

68.4 parts of the obtained wet cake of the bisazo compound represented by the above formula (106) was added to 400 parts of water, stirred and suspended, and 25% sodium hydroxide was used to make the aforementioned suspension pH 9.0, and then add 13.8 parts of 40% sodium nitrite aqueous solution to it. The obtained suspension was dropped into a mixed liquid of 100 parts of water and 40 parts of 35% hydrochloric acid to prepare a diazonium base liquid. On the other hand, 4.5 parts of 8-aminonaphthalene-2-sulfonic acid was added to 150 parts of water and dissolved in a 25% aqueous sodium hydroxide solution while adjusting the pH to 6 to 8. In this solution, the diazonium-based solution of the above formula (106) is maintained at pH 4.5 to 6.0 with 35% hydrochloric acid as needed and dropped, and the coupling reaction is completed by stirring. Thereafter, after salting out with sodium chloride, filtration was performed to obtain 100 parts of wet cake of the parazo compound represented by the following formula (107).

Add 50 parts of the obtained wet cake of the parazo compound represented by the above formula (107) to 200 parts of water, stir to suspend it, and use 25% sodium hydroxide to make the aforementioned suspension pH 9.0, and then add 6.9 parts of 40% sodium nitrite aqueous solution to it. The obtained suspension was dropped into a mixed liquid of 100 parts of water and 25 parts of 35% hydrochloric acid to prepare a diazonium base liquid. On the other hand, 10.0 parts of 1,5-dihydroxynaphthalene-2,6-disulfonic acid was added to 100 parts of water, and a 25% sodium hydroxide aqueous solution was used to adjust the pH to 6 to 8 and dissolve. In this solution, the diazonium-based solution of the above formula (107) is maintained at Ph 6.5 to 8.0 with 35% hydrochloric acid as needed and dropped, followed by stirring to complete the coupling reaction. Thereafter, after salting out with sodium chloride, filtration and drying were performed to obtain 5.0 parts of the water-soluble dichroic dye shown in the following [Compound Example 1-29].

<Production of Polarizing Element Using [Compound Example 1-5]>

The polyvinyl alcohol film (VF-PS #7500 manufactured by KURARAY) with a saponification degree of 99% or more and an average degree of polymerization of 2400 was immersed in warm water at 45°C for 3 minutes, and then subjected to swelling treatment to extend 1.30 times. In a 45°C dyeing solution containing 1500 parts by mass of water, 1.5 parts by mass of anhydrous Glauber's salt, and 0.30 parts by mass of [Compound Example 1-5], immerse the swollen film for 15 minutes so that the film contains the [Compound Example 1-5] Shows the dichroic dye. The obtained film was immersed in a 40°C aqueous solution containing 20 g/l of boric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) for 1 minute. The immersed film was placed in an aqueous solution (pH 5.3) at 50°C containing 30.0 g/l of boric acid, and subjected to an extension treatment for 5 minutes, extending 5.0 times. By maintaining its tension state, while immersing in water at 25°C for 20 seconds, the resulting film was washed. The cleaned film was dried at 70°C for 9 minutes to obtain a polarizing element.

<Production of Polarizing Element Using [Compound Example 1-29]>

The polyvinyl alcohol film (VF-PS #7500 manufactured by KURARAY) with a saponification degree of 99% or more and an average degree of polymerization of 2400 was immersed in warm water at 45°C for 3 minutes to swell and stretch 1.30 times. In a 45°C dyeing solution containing 1500 parts by mass of water, 1.5 parts by mass of anhydrous Glauber's salt, and 0.30 parts by mass of [Compound Example 1-29], immerse the swollen film for 15 minutes so that the film contains the [Compound Example 1-29] Shows the dichroic dye. The obtained film was immersed in a 40°C aqueous solution containing 20 g/l of boric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) for 1 minute. The immersed film was placed in a 50°C aqueous solution (pH 7.0) containing 22.0 g/l of boric acid and 8.0 g/l of borax, and subjected to an extension treatment for 5 minutes to extend 5.0 times. By maintaining its tension state, while immersing in water at 25°C for 20 seconds, the resulting film was washed. The cleaned film was dried at 70°C for 9 minutes to obtain a polarizing element.

(Determination of the maximum absorption wavelength of the polarizing element, its transmittance and the degree of polarization)

For the polarizing element produced using the above [Compound Example 1-5] and the polarizing element produced using the above [Compound Example 1-29], the maximum absorption wavelength and the monomer transmittance (%) of the wavelength were measured , And its polarization (%). In the measurement of the maximum absorption wavelength (nm, λmax) of the polarizing element and the calculation of the degree of polarization, the parallel transmittance (Ky, %) and orthogonal transmittance (Kz, %) when polarized light is incident are used with A spectrophotometer (U-4100 manufactured by Hitachi, Ltd.) of a Glan-Thompson polarizing plate (polarizing plate for 200 to 2600 nm) was measured by making polarized light incident on the measurement sample. Here, the so-called parallel transmittance (Ky) is the transmittance when the absorption axis of the absolute polarizer used in the measurement is parallel to the absorption axis of the polarizing element, and the orthogonal transmittance (Kz) is determined during the measurement. The absorption axis of the absolute polarizer used and the absorption axis of the polarizing element represent the transmittance when orthogonal. The parallel transmittance and orthogonal transmittance of each wavelength are measured at intervals of 5 nm from 380 to 1200 nm. Using the measured values, calculate the monomer transmittance of each wavelength from the following formula (i), and calculate the polarization degree of each wavelength from the following formula (ii) to obtain the maximum polarization degree at 380 to 1200 nm. Absorption wavelength (λmax), and monomer transmittance. Also, convert Ky and Kz into absorbance, and the absorbance obtained from here Calculate the highest absorbance ratio as the dichroic ratio (Rd). In addition, areas with a two-color ratio of 5 or more and areas with a two-color ratio of 10 or more were confirmed.

Table 2 shows the optical characteristics of the wavelength (λmax) at which the degree of polarization of the obtained polarizer is the highest, and the results of the wavelength in the region where Rd is 5 or more and Rd is 10 or more.

(Formula 1) monomer penetration rate (%)=(Ky+Kz)/2 (i)

(Equation 2) Polarization (%)=[(Ky-Kz)/(Ky+Kz)]×100 (ii)

[Table 2]

As shown in Table 1, the polarizing element produced using the above [Compound Example 1-5] and the polarizing element produced using the above [Compound Example 1-29] have high polarization at the maximum absorption wavelength (λmax) Performance, any one of them has absorption anisotropy of dichroic ratio (Rd) 5 or more in the near-infrared region. In addition, it is a polarizing element in which a band with a dichroic ratio of 10 or more exists at 1080 nm and a high degree of polarization in a wide-band region.

<Production of Adhesive Sheets on Both Sides>

According to the formula of Example 1 of Patent Document 9, a double-sided adhesive sheet for bonding the substrate and the polarizing element was obtained. The content of Patent Document 9 is incorporated into the specification of this case by reference.

Specifically, 94 g of n-butyl acrylate, 1 g of 2-hydroxyethyl acrylate, and 5 g of N,N-dimethylacrylamide were dissolved in 185 g of ethyl acetate, and 0.05 g of azobisisobutyronitrile was added. Polymerize at 70°C for 5 hours while An acrylic resin copolymer solution is obtained. The obtained acrylic copolymer has a weight average molecular weight obtained by gel permeation chromatography (GPC) in terms of polystyrene: 1,100,000. Then, ethyl acetate was added to the obtained copolymer solution, and it prepared so that a resin component might become 22.5% by weight, and an acrylic adhesive was obtained. The obtained acrylic adhesive with a resin content of 22.5% by weight was 79 parts by weight in terms of solid content, an isocyanate-based crosslinking agent (CORONATE RTMHL manufactured by TOSOH) 0.035 parts by weight, and 3-glycidoxypropyl trimethyl Oxysilane (KBM-403 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.009 parts by weight, dibutyltin dilaurate (manufactured by Junsei Chemical Co., Ltd.) 0.002 parts by weight, 3-propenyloxypropyl trimethoxy silane having an acrylic group-containing alkoxysilane 17 parts by weight of silane (KBM-5103 manufactured by Shin-Etsu Chemical Co., Ltd.), 2 parts by weight of KAYARAD R-115 (manufactured by Nippon Kayaku Co., Ltd.) as a bifunctional photopolymerizable compound, and IRGACURE (IRGACURE) as a photopolymerization initiator 2 parts by weight of -184 (manufactured by BASF Corporation) and 32 parts by weight of 2-butanone were mixed to obtain the compounding composition used in the present invention. Methyl ethyl ketone was added so that the solid content of the obtained compound composition became 20 parts by weight, and the mixture was mixed for 1 hour to obtain the compound composition of the present invention for adhesive sheets. Using a coater, the obtained compounding composition was sandwiched between two release films (polyethylene terephthalate films) and formed into a sheet. The obtained sheet has a thickness of 20 μm and is used as a double-sided adhesive sheet for a laminate.

<The influence of the substrate on the retention rate of the boron compound in the hydrophilic polymer film>

(1) The substrate as the test object

Resin substrate-1

10 parts by weight of PET-30 (neopentylerythritol triacrylate) manufactured by Nippon Kayaku Co., Ltd., 5 parts by weight of toluene, and 0.6 parts by weight of 1-hydroxycyclohexyl phenyl ketone (IRGACURE 184 manufactured by BASF) were mixed and irradiated Formed by ultraviolet rays.

Resin substrate-2

5 parts by weight of PET-30 (neopentyl erythritol triacrylate) manufactured by Nippon Kayaku Co., Ltd., 5 parts by weight of FA-511A (dicyclopentenyl acrylate) manufactured by Hitachi Chemical Co., Ltd., 5 parts by weight of toluene, and 1-hydroxyl 0.6 parts by weight of cyclohexyl phenyl ketone (IRGACURE 184 manufactured by BASF Corporation) was mixed and irradiated with ultraviolet rays to form it.

Resin substrate-3

10 parts by weight of PEG-400DA (polyethylene glycol diacrylate) manufactured by Nippon Kayaku Co., Ltd., 5 parts by weight of toluene, and 0.6 part by weight of 1-hydroxycyclohexyl phenyl ketone (IRGACURE 184 manufactured by BASF) were mixed and irradiated Formed by ultraviolet rays.

Resin substrate-4

Cycloolefin membrane (trade name: Zeonor) manufactured by Japan's ZEON company was used.

Resin substrate-5

According to the description of Example 1 of International Publication WO2006-112223, the acrylic resin was formed into a film of 40 μm.

Inorganic substrate-1

Use the whiteboard transparent glass substrate made by Kawamura Kuzou.

Inorganic substrate-2

The crystal substrate made by Iwate Murata Manufacturing Co., Ltd. is used.

TAC film

For comparison, a TAC film (TD-80U manufactured by Fuji Film Co., Ltd.) was used as a test object.

(2) Preparation of measurement samples

A polyvinyl alcohol film (VF-PS #7500 manufactured by KURARAY), which is a hydrophilic polymer film with a saponification degree of 99% or higher and an average degree of polymerization of 2400, was immersed in warm water at 45°C for 3 minutes, swelled, and stretched 1.30 times. Soak the swollen membrane in warm water at 45°C for 15 minutes, and immerse the resulting membrane in boric acid (Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) 20 g/l in an aqueous solution at 40°C for 1 minute. The immersed film is stretched to 5.0 times by stretching in an aqueous solution containing 30.0 g/l of boric acid at 50°C for 5 minutes. While maintaining the tensioned state of the obtained film, it is immersed in water at 25°C for 20 seconds, thereby performing a washing treatment. The washed film was dried at 70°C for 9 minutes to obtain a polyvinyl alcohol film containing a boron compound. The polyvinyl alcohol film containing the obtained boron compound is prepared by dissolving polyvinyl alcohol (NH-26 manufactured by VAM & POVAL Co., Ltd., Japan) at 4% in water as an adhesive. A plain film (TD-80 manufactured by Fujifilm Co., Ltd., hereinafter, abbreviated as TAC film) is laminated on one side, and then each substrate is laminated on the other side via the above-mentioned two-sided adhesive sheet. The so-called substrate/two-sided adhesive sheet/contains The composition of boron compound polyvinyl alcohol film/PVA adhesive layer/TAC film/adhesive sheet on both sides/glass was used to prepare measurement samples.

(3) Test method

After placing the obtained measurement sample in an environment of 80°C and a relative humidity of 90%RH for 1000 hours, only the polyvinyl alcohol film containing the boron compound was taken out, and the amount of boron compound remaining on the polyvinyl alcohol film was measured.

The content of boron compound is firstly, dissolve about 0.05g of polyvinyl alcohol film containing boron compound in 50g of water, and boil for 60 minutes to dissolve or completely swell the polyvinyl alcohol film, cool to normal temperature, add D(-)-mannan 3 g of alcohol, 0.05 mol/l sodium hydroxide aqueous solution was dropped to pH=8.4, and the concentration of boric acid was calculated from the dropped amount as the content of the boron compound. The content of the boron compound is obtained by formula (iii). At this time, when only sodium hydroxide is dripped into B system, the dripping amount (ml) of pH=8.4 is displayed. F represents the factor of sodium hydroxide aqueous solution.

(Formula 3) Boron compound content (%)=(NaOH titer [ml]-B)×F×0.30915/weight of polarized light-emitting element [g] (iii)

The respective substrates supplied to the measurement of the moisture permeability and the retention of the boron compound are shown in Table 3 below together with the test results.

[table 3]

As described above, it can be seen that the resin substrate-3 and the TAC film do not satisfy the condition a) above.

<Determination of moisture permeability>

(1) Preparation of test sample with resin substrate

Resin substrate-1

The semi-suned kraft paper (taken from TOTSUYA ECHO Co., Ltd.) is formed by anchoring and coating polyvinyl alcohol with a solid content concentration of 5% to a thickness of 1 μm, and blending PET-30 (Nippon Kayaku Co., Ltd.) Alcohol triacrylate) 10 parts by weight, 5 parts by weight of toluene, and 0.6 parts by weight of 1-hydroxycyclohexyl phenyl ketone (IRGACURE 184 manufactured by BASF) were prepared to form a resin substrate-1 composition. The composition was coated on the semi-suned kraft paper anchor-coated with polyvinyl alcohol so that the resin solid content after solvent volatilization became 5 μm thickness to prepare a measurement sample with a resin substrate-1.

Resin substrate-2

In addition to replacing 10 parts by weight of Nippon Kayaku Corporation PET-30 (neopentyl erythritol triacrylate) with 5 parts by weight of Nippon Kayaku Corporation PET-30 (neopentyl erythritol triacrylate), and Hitachi Chemical's FA -511A (acrylic Except for 5 parts by weight of dicyclopentenyl acid), the rest is the same to prepare a measurement sample having a resin substrate-2.

Resin substrate-3

Except that 10 parts by weight of PET-30 (neopentylerythritol triacrylate) manufactured by Nippon Kayaku Co., Ltd. is replaced by 10 parts by weight of PEG-400DA (polyethylene glycol diacrylate) manufactured by Nippon Kayaku Co., Ltd., the rest is the same. , Prepare a measurement sample with resin substrate-3.

Resin substrate-4

Cycloolefin membrane (trade name: Zeonor) manufactured by ZEON Corporation of Japan was used as a measurement sample.

Resin substrate-5

According to the description of Example 1 of International Publication WO2006-112223, a film made by forming an acrylic resin into a film of 40 μm was used as a measurement sample.

Inorganic substrate-1

A whiteboard transparent glass substrate made by Kawamura Kuzou was used as the inorganic substrate-1.

Inorganic substrate-2

A crystal substrate made by Iwate Murata Manufacturing Co., Ltd. was used as the inorganic substrate-2.

(2) Measurement of moisture permeability

The moisture permeability of each substrate was measured using an L80-5000 water vapor permeability meter (manufactured by Systech Instruments).

The measurement results of the moisture permeability of the substrates used in the examples of this case are shown in Table 4 below. In Table 4, the ND system represents the lower limit of measurement or less.

[Table 4]

It can be seen that the resin substrate-3 does not satisfy the above-mentioned condition b).

<Example 1>

The resin substrate-1 was placed on a cellulose triacetate film (TD-80U manufactured by Fujifilm Co., Ltd., hereinafter referred to as TAC film) so that the film thickness after formation was 5 μm, and a TAC film having the resin substrate-1 was produced. After immersing the TAC film with the resin substrate-1 in a pH=11 aqueous sodium hydroxide solution for 10 minutes, it is immersed in a pH=6 aqueous solution for 1 minute. Using 4% polyvinyl alcohol aqueous solution (NH-26 4% aqueous solution manufactured by Japan VAM & POVAL Co., Ltd.), the TAC surface of the TAC film with resin substrate-1 obtained by the treatment, and the above-mentioned [Compound Example 1-5] The produced polarizing element is then connected. Furthermore, in a manner that the polarizing element is held by the TAC film, a 4% polyvinyl alcohol aqueous solution is used to bond the TAC film that has only undergone saponification treatment. On the TAC surface of the film bonded with the adhesive, the adhesive PTR-3000 manufactured by Nippon Kayaku Co., Ltd. is coated so that the thickness after drying becomes 20 μm to form an adhesive layer, and the adhesive layer is formed on the side of the glass. , Get a polarizing plate. That is, a polarizing plate produced by using the resin substrate-1/TAC film/adhesive layer/[Compound Example 1-5] to become a polarizing element/adhesive layer/TAC film/adhesive layer/glass was obtained.

<Example 2>

In the above-mentioned Example 1, except that the above-mentioned resin substrate-1 was changed to the above-mentioned resin substrate-2, in the same manner as in Example 1, a resin substrate-2/TAC film/adhesive layer/[Compound Example 1 -5] to make and become a polarizing plate of polarizing element/adhesive layer/TAC film/adhesive layer/glass.

<Example 3>

In the above-mentioned Example 1, except that the TAC film formed with the resin substrate-1 was changed to a cycloolefin film (Zeonor manufactured by ZEON Corporation, Japan) applied corona treatment, the same method as in Example 1 was used to obtain a cycloolefin film. Film/adhesive layer/[Compound Example 1-5] is produced and becomes a polarizing plate of polarizing element/adhesive layer/TAC film/adhesive layer/glass.

<Example 4>

Using the two sides of the polarizing element of [Compound Example 1-5] used in Example 1 above, the above-mentioned two-sided adhesive sheet was laminated, one side was laminated with glass, and the other side was laminated with crystal to obtain a glass /Adhesive sheet on both sides/[Compound Example 1-5] to produce and become a polarizing element/adhesive sheet on both sides/crystal polarizing plate.

<Example 5>

In the above-mentioned Example 1, except that the TAC film formed with the resin substrate-1 was changed to the resin substrate-5 with the easy-adhesive layer formed, and the polarizing element using [Compound Example 1-5] was changed to use the above-mentioned [Compound Example 1-29] Except for the polarizing element produced, in the same manner as in Example 1, an acrylic film/adhesive layer/[Compound Example 1-29] was obtained to produce and became a polarizing element/adhesive layer/TAC film /Adhesive layer/Glass Polarizing plate of Example 5.

<Example 6>

In the above-mentioned Example 2, except that the polarizing element produced using [Compound Example 1-5] was changed to the polarizing element produced using the above-mentioned [Compound Example 1-29], it was carried out in the same manner as in Example 2 to obtain a Resin substrate-2/TAC film/adhesive layer/[Compound Example 1-29] was produced and became a polarizing plate of polarizing element/adhesive layer/TAC film/adhesive layer/glass.

<Comparative Example 1>

In the above Example 1, except that the resin substrate-1 is not used, the rest is the same as in Example 1. A TAC film/adhesive layer/[Compound Example 1-5] is obtained to produce and become a polarizing element/adhesive The polarizing plate of Comparative Example 1 of agent layer/TAC film/adhesive layer/glass.

<Comparative Example 2>

In the above-mentioned Example 1, except that the above-mentioned resin substrate-3 was used instead of the resin substrate-1, in the same manner as in Example 1, a resin substrate-3/TAC film/adhesive layer/[Compound Example 1-5 ] To produce and become a polarizing element/adhesive layer/TAC film/adhesive layer/glass polarizing plate.

The obtained polarizing plates of Examples 1 to 6 and Comparative Examples 1 to 2 were placed in an environment with a relative humidity of 90%RH and 80°C for 1000 hours, and the Ky(%) in 950nm before and after the high temperature and high humidity treatment was confirmed , Kz (%), monomer transmittance (%), polarization (%), and changes in the optical properties of Rd. The results are shown in Table 5.

[table 5]

As shown in Table 5 above, in Comparative Examples 1 and 2, the Ky system at 950 nm after the above application is greatly reduced from 79.82% to 48.58%, and from 79.25% to 49.83%, respectively, and the monomer penetration rate is greatly reduced. Departments were significantly reduced from 39.97% to 24.92%, and from 39.67% to 25.47%. In contrast to this, it can be seen that in Examples 1 to 6, Ky and monomer transmittance are the largest change in monomer transmittance, and Ky is only changed from 81.98% to 80.54%. The penetration rate varies from 42.30% to 41.43%, which is about 0.87%, and it maintains approximately the initial state. From this situation, it can be seen that the polarizing plates of Examples 1 to 6 have extremely high damp heat durability.

<Light resistance test>

For the polarizing plates produced in the above-mentioned Example 4 and Comparative Example 1, a xenon arc tester (manufactured by SUGA Tester; SX-75) at 150W, an ambient temperature of 70°C, and an ambient humidity of 50%, was used in Example 4 On the glass side, in Comparative Example 1, a 240-hour light irradiation test was performed from the TAC film side. Confirm the changes in the optical properties of Ky (%), Kz (%), monomer transmittance (%), polarization (%), and Rd at 950 nm before and after light irradiation. The results are shown in Table 6.

[Table 6]

From the results of Table 6, in the light resistance test, the 950 nm change of Example 4 was only 0.1145% to 0.2615%, but the comparative example 1 was greatly changed from 0.1132 to 5.2350%. Even in the degree of polarization, the Example 4 system maintained 99% or more, while the Comparative Example 1 system decreased to 88.08%. In the dichroic ratio (Rd), the Example 4 system only changed from 29.2 to 23.0, but the Comparative Example 1 system decreased from 30.1 to 15.4. From the above, it can be seen that the polarizing plate of Example 4 is in the near-infrared region and has high light resistance.

[Industrial Utilization Possibility]

The polarizing plate of this case is a polarizing plate that can have a high degree of polarization in the infrared region, or the visible light region to the infrared region, and has high durability. The obtained polarizing plate also has high light resistance when exposed to strong light for a long time under high temperature, high humidity or high temperature. Therefore, the polarizing plate of this case can be applied to sensors, lenses, switching elements, isolators, cameras, indoor and outdoor measuring devices or driving sensor modules that require high degree of polarization. In addition, it can be suitably used for infrared-sensing machines, such as infrared panels, spatial infrared touch modules, etc., and can be used in conjunction with conventional displays such as electronic devices, timepieces, notebook computers, word processors, LCD TVs, polarized lenses, Polarized glasses, car navigation systems, etc. can be used together to provide not only visible light displays, but also modules that use infrared light.

Claims (23)

A polarizing plate, comprising: a polarizing element composed of a hydrophilic polymer film containing a near-infrared absorbing dye, and a substrate provided on one or both sides of the film; The substrate has at least any one of the following characteristics a) and b): a) When the hydrophilic polymer film contains a boron compound, after the polarizer is exposed to a relative humidity of 90%RH and 80°C for 1000 hours, the time before the exposure is set as 100, the content of the hydrophilic polymer film The quality of the boron compound contained is kept above 20; b) According to the JIS Z 0208 moisture permeability test, the moisture permeability of the substrate in an environment with a relative humidity of 90%RH and 40°C is 0 to 1500g/m ² in 24 hours. The polarizing plate according to claim 1, wherein at least one of the substrates is a resin substrate having the characteristics of b). The polarizing plate according to claim 2, wherein a substrate is provided on both sides of the hydrophilic polymer film, and an inorganic substrate or a resin substrate having the characteristics of b) is provided on the side opposite to the resin substrate. The polarizing plate according to any one of claims 1 to 3, wherein the hydrophilic polymer film is selected from the group consisting of polyvinyl alcohol-based resins, amylose-based resins, starch-based resins, cellulose-based resins, and polyvinyl alcohol-based resins. It is composed of acrylate resins and resins in the group consisting of these derivatives, and contains a boron compound. The polarizing plate according to any one of claims 2 to 4, wherein the resin-made substrate includes a resin selected from the group consisting of silicon-based resin, (meth)acrylic resin, cycloolefin-based resin, polyester-based resin, and polycarbonate One or more resins in the group consisting of ester resins. The polarizing plate according to any one of claims 2 to 5, wherein the resin substrate includes a film obtained by polymerizing a polymerizable monomer composition, and the polymerizable monomer composition contains Three or more (meth)acrylic (meth)acrylate compounds. The polarizing plate according to claim 6, wherein the (meth)acrylate compound has a structure selected from the group consisting of neopentyl erythritol skeleton, neopentyl glycol skeleton, trimethylolpropane skeleton, and dicyclopentadiene skeleton. Any skeleton in the group. The polarizing plate according to claim 6 or 7, wherein the (meth)acrylate compound is 15% by mass or more in all monomers in the polymerizable monomer composition in terms of solid content concentration. The polarizing plate according to any one of claims 3 to 8, wherein the inorganic substrate includes any one of glass, quartz, sapphire, crystal, and spinel. The polarizing plate according to any one of claims 2 to 9, wherein the thickness of the resin substrate is 0.5 μm to 10 μm. The polarizing plate according to any one of claims 4 to 10, wherein the hydrophilic polymer film contains polyvinyl alcohol resin or a derivative thereof. ] The polarizing plate according to any one of claims 1 to 11, wherein the near-infrared absorbing dye is an azo compound represented by the following formula (1),

In formula (1), A ¹ is optionally substituted phenyl, optionally substituted naphthyl or optionally substituted heterocyclic group, and A ² , A ³ and A ⁴ are each independently optionally substituted The phenyl group or the naphthyl group that may have a substituent, k represents an integer of 0 or 1; R ¹ is a hydroxyl group, an alkoxy group with 1 to 4 carbons or a substituted or unsubstituted amino group, and m represents 0 to An integer of 5; M represents hydrogen, a metal ion or an ammonium ion, and n represents an integer of 1 or 2; the hydrogen atoms of ring a and ring b can be independently substituted with substituent R ¹ respectively, and between ring a and ring b Either or both of the hydrogen atoms are substituted with the substituent SO ₃ M. The polarizing plate according to claim 12, wherein A ² , A ³ and A ⁴ in the above formula (1) are independently represented by the following formula (2) or (3), A ² , A ³ And ^{at least one of A 4} is shown in formula (2),

In formula (2), R ² represents a hydroxyl group, an aliphatic hydrocarbon group with 1 to 4 carbons, an alkoxy group with 1 to 4 carbons, a substituted or unsubstituted amine group, or a sulfo group substituted with 1 to 4 carbons. The alkoxy of, m ² represents an integer from 0 to 6; M represents hydrogen, metal ion or ammonium ion, and n ³ represents an integer from 0 to 2;

In formula (3), R ³ and R ⁴ each independently represent a hydrogen atom, an aliphatic hydrocarbon group with 1 to 4 carbons, an alkoxy group with 1 to 4 carbons, and an alkane with 1 to 4 carbons substituted with a hydroxyl group. An oxy group or an alkoxy group having 1 to 4 carbons substituted with a sulfo group. The polarizing plate according to claim 12 or 13, wherein the azo compound of the above formula (1) is a compound represented by the following formula (4);

In formula (4), A ¹ , A ² , A ³ , A ⁴ , M, n, and k are the same as the above formula (1), and the hydrogen atom of one or both of ring a and ring b It is substituted with the substituent SO ₃ M. The polarizing plate according to any one of claims 12 to 14, wherein A ¹ in the above formula (1) or (4) is selected from alkoxy groups having 1 to 4 carbons substituted with a hydroxyl group and a sulfo group And a naphthyl group substituted with one or more substituents in the group consisting of a sulfo group. The polarizing plate according to any one of claims 12 to 14, wherein, in the above formula (1) or (4), A ¹ is represented by the following formula (5);

In formula (5), n ⁴ represents an integer of 1 or 2. The polarizing plate according to any one of claims 12 to 14, wherein A ¹ in the above formula (1) or (4) is a phenyl group substituted with at least one substituent selected from a nitro group and a sulfo group . The polarizing plate according to any one of claims 12 to 14, wherein ^{the heterocyclic group which may have a substituent in A 1} of the above formula (1) or (4) is selected from (6) to (8) The bases in the group consisting of the bases shown;

X in formulas (6) to (8) are independently halogen groups, nitro groups, hydroxyl groups, aliphatic hydrocarbon groups with 1 to 4 carbons, alkoxy groups with 1 to 4 carbons, and carbons substituted with sulfo groups. Aliphatic hydrocarbon groups of 1 to 4, aliphatic hydrocarbon groups of 1 to 4 carbons substituted with hydroxyl groups, aliphatic hydrocarbons of 1 to 4 carbons substituted with carboxyl groups, alkoxy groups of 1 to 4 carbons substituted with sulfo groups Group, an alkoxy group with 1 to 4 carbons substituted by a hydroxyl group, or an alkoxy group with 1 to 4 carbons substituted with a carboxyl group, q ¹ represents an integer from 0 to 4, and q ² represents an integer from 0 to 6 ; M represents hydrogen, metal ion, or ammonium ion, n ¹ and n ² each independently represent an integer from 0 to 3; in each formula * represents the bonding position of the azo bond. The polarizing plate according to any one of claims 1 to 18, wherein at least 700 to 1500 nm has: absorbance on the axis showing the highest transmittance for polarized light, and the lowest absorbance for polarized light The ratio of absorbance on the axis of transmittance to absorbance is in the wavelength range of 5 or more. The polarizing plate according to any one of claims 12 to 19, which further contains one or more kinds of organic dyes other than the azo compound represented by the above formula (1). The polarizing plate according to claim 20, which is displayed in neutral gray. An optical device provided with the polarizing plate according to any one of claims 1 to 21. A display device is provided with the polarizing plate according to any one of claims 1 to 21, or the optical device according to claim 22.