KR20190096816A - Circular polarizing plate and optical display device - Google Patents

Abstract

Provided is a circular polarizing plate with suppressed coloring of reflected light. In addition, provided is an optical display device having such a circular polarizing plate and capable of good image display. The circular polarizing plate comprises a polarizing layer, a retardation layer, and a light absorbing layer. The retardation layer satisfies the following expressions (1) 0.80 < Re(450)/Re(550) < 1.00, and (2) 1.00 < Re(650)/Re(550) < 1.30, when an in-plane retardation value for light having a wavelength of λ nm is set to Re (λ), and the light absorbing layer has a base material layer and a pigment dispersed in the base layer. The pigment has a maximum absorption wavelength in a wavelength band of 390 to 430 nm. The circular polarizing plate has sum total of an integration value of the transmittance of the retardation layer in the wavelength band of 380 to 450 nm, and an integration value of the transmittance of the light absorbing layer in the wavelength band of 380 to 450 nm to be 5000 or less.

Description

Circular polarizer and optical display device {CIRCULAR POLARIZING PLATE AND OPTICAL DISPLAY DEVICE}

The present invention relates to a circularly polarizing plate and an optical display device.

Conventionally, a circularly polarizing plate is used as an optical film which suppresses reflection of external light in a display apparatus (for example, refer patent document 1). Such an optical film is known as a so-called antireflection film. The circular polarizing plate has a polarizer provided on the light incidence side and a phase difference layer (λ / 4 plate) provided on the side opposite to the light incidence side with respect to the polarizer.

The circularly polarizing plate suppresses reflection of external light as follows.

First, external light incident on the circularly polarizing plate is converted into linearly polarized light by a polarizer, and then converted into circularly polarized light in the retardation layer. After the circularly polarized light reaches the display device provided with the circularly polarizing plate, the phase is reflected by a fixed end on the surface of the display device, thereby reflecting the phase by? / 2.

Thereafter, the reflected circularly polarized light is incident again on the retardation layer and converted into linearly polarized light. At that time, since the circularly polarized light is fixed-stage reflected, the linearly polarized light to be converted has a relationship in which the linearly polarized light, which has previously been transmitted through the polarizer and converted to external light, is orthogonal to the vibration plane. As a result, the external light reflected from the surface of the display device cannot pass through the polarizer and is absorbed or reflected by the polarizer without being emitted to the outside. In this manner, the circularly polarizing plate suppresses reflection of external light.

Patent Document 1: Japanese Patent Application Laid-Open No. 2014-170221

The retardation value of the retardation layer is different depending on the wavelength of light. Therefore, even if it is the same retardation layer, the performance of a retardation layer changes with wavelength of light. For example, in a retardation layer capable of converting linearly polarized light having a wavelength near green into circularly polarized light, a problem arises in that linearly polarized light having a wavelength near red or blue cannot be converted into circularly polarized light satisfactorily.

In a circularly polarizing plate whose main purpose is to suppress reflection of external light, a design often uses a phase difference layer capable of converting light near a high visibility into an ideal circularly polarized light. In the circular polarizing plate having such a design, it is easy to reduce glare of external light. On the other hand, in such a circularly polarizing plate, the suppression of reflection of light having a wavelength near red or blue tends to be insufficient, and the reflected light tends to be colored.

Therefore, when the conventional circular polarizing plate is used as the antireflection plate as described above, the image quality may be deteriorated due to the colored reflected light. Therefore, the circularly-polarizing plate which suppressed reflected light color was calculated | required.

This invention is made | formed in view of such a situation, and an object of this invention is to provide the circularly-polarizing plate which suppressed coloring of reflected light. Moreover, it aims at providing the optical display device which has such a circularly polarizing plate and is capable of favorable image display.

In order to solve the said subject, one aspect of this invention is equipped with a polarizer layer, a phase difference layer, and a light absorption layer, When the said phase difference layer makes in-plane phase difference value with respect to the light of wavelength (lambda) nm as Re ((lambda)), The following formulas (1) and (2) are satisfied, and the light absorption layer has a base layer and a pigment dispersed in the base layer, and the dye has a maximum absorption wavelength in a wavelength band of wavelength 390 to 430 nm. A total polarizing plate having a total value of the integrated value of the transmittance of the phase difference layer in the wavelength band of 380 to 450 nm and the integrated value of the transmittance of the light absorbing layer in the wavelength band of wavelength of 380 to 450 nm is 5000 or less. .

0.80 <Re (450) / Re (550) <1.00... (One)

1.00 <Re (650) / Re (550) <1.30... (2)

In one aspect of the present invention, the base material layer may be a pressure-sensitive adhesive layer or an adhesive layer.

In one aspect of the present invention, the transmittance T (λ) of the light absorbing layer with respect to light having a wavelength of λnm may be a structure satisfying the following formulas (i) to (iii).

T (390) &lt; 85%. (i)

T (410) ≤ 98%. (ii)

T (430) ≤ 99%. (iii)

Moreover, one aspect of this invention provides the optical display device which has an optical display panel and said circularly polarizing plate bonded by the display surface of the said optical display panel.

In one aspect of the present invention, the circularly polarizing plate is disposed such that the polarizer layer is opposite to the optical display panel with respect to the phase difference layer, and the front polarizing plate is provided with a front plate on the polarizer layer side. Also good.

In one aspect of the present invention, a touch sensor may be provided between the display surface and the circular polarizing plate.

According to this invention, the circularly-polarizing plate which suppressed coloring of reflected light can be provided. Furthermore, it is possible to provide an optical display device having such a circular polarizing plate and capable of good image display.

FIG. 1: is sectional drawing which shows the structure of the optical display device 10 provided with the circularly polarizing plate 1 and the optical display panel 20. As shown in FIG.
2 is an explanatory diagram for explaining the design idea of the phase difference layer 3.
It is explanatory drawing which shows the modification of an optical display device.

Hereinafter, the circular polarizing plate which concerns on this embodiment is demonstrated, referring drawings. In addition, in all the following drawings, in order to make drawing clear, a dimension, a ratio, etc. of each component are changed suitably.

[Definition of Terms and Symbols]

Definitions of terms and symbols in the present specification are as follows.

(1) refractive index (nx, ny, nz)

"Nx" is a refractive index of the direction in which the in-plane refractive index becomes maximum (that is, the slow axis direction).

"Ny" is the refractive index of the direction orthogonal to the slow axis in surface.

"Nz" is a refractive index in the thickness direction.

(2) In-plane phase difference value

In-plane phase difference value Re ((lambda)) says in-plane phase difference value of the film in 23 degreeC and wavelength (lambda) (nm). Re ((lambda)) is calculated | required by Re ((lambda)) = (nx-ny) xd, when making thickness of a film d (nm).

Here, nx, ny, and nz used for calculation of Re ((lambda)) are the values measured using the light of wavelength (lambda) (nm) at 23 degreeC. d is the value measured at 23 degreeC.

In the following description, the in-plane retardation value may be referred to as an "in-plane retardation value".

(3) phase difference value in the thickness direction

In-plane phase difference value Rth ((lambda)) means the phase difference value of the thickness direction of a film in 23 degreeC and wavelength (lambda) (nm). Rth ((lambda)) is calculated | required by Rth ((lambda)) = ((nx + ny) / 2-nz) xd, when making thickness of a film d (nm).

Here, nx, ny, and nz used for calculation of Rth ((lambda)) are the values measured using the light of wavelength (lambda) (nm) at 23 degreeC. d is the value measured at 23 degreeC.

(4) Nz coefficient

Nz coefficient is a value calculated | required by Nz coefficient = Rth ((lambda)) / Re ((lambda)) + 0.5.

FIG. 1: is sectional drawing which shows the structure of the optical display device 10 provided with the circularly polarizing plate 1 and the optical display panel 20 of this embodiment.

As shown in FIG. 1, the circular polarizing plate 1 includes a polarizer layer 2 and a phase difference layer 3 disposed on one surface side of the polarizer layer 2. In addition, the protective films 5 and 6 are arrange | positioned at both surfaces of the polarizer layer 2, respectively.

On one surface side of the polarizer layer 2, the phase difference layer 3 is laminated via the light absorption layer 7. It is preferable that the phase difference layer 3 and the light absorption layer 7 are laminated in contact with each other. The adhesive layer 8 for laminating | stacking on the optical display panel 20 mentioned later is arrange | positioned at the surface on the opposite side to the polarizer layer 2 of the phase difference layer 3. In addition, a peeling film (not shown) is bonded to the surface of this adhesive layer 8 until it is used. In addition, the adhesive layer 8 is formed of an acrylic adhesive, for example.

(Polarizer layer)

The polarizer layer 2 passes light of linearly polarized light having a polarization plane in a specific direction. Light passing through the polarizer layer 2 becomes linearly polarized light vibrating in the transmission axis direction of the polarizer. The thickness of the polarizer layer 2 is about 1 micrometer-about 80 micrometers, for example.

Examples of the polarizer layer 2 include hydrophilic polymer films such as polyvinyl alcohol films, partially formalized polyvinyl alcohol films, and ethylene / vinyl acetate copolymerized partial saponified films, and dichroic materials such as iodine and dichroic dyes. By the dyeing treatment and the stretching treatment can be used. As the polarizer layer 2, a polyene-based alignment film or the like such as a dehydrated product of polyvinyl alcohol or a dehydrochloric acid treated product of polyvinyl chloride can be used. Among these, since the polarizer layer 2 obtained by dyeing a polyvinyl alcohol-type film with iodine and uniaxially stretching is excellent in an optical characteristic, it is preferable.

Dyeing by iodine is performed by immersing a polyvinyl alcohol-type film in aqueous solution of iodine, for example. It is preferable that the draw ratio of uniaxial stretching is 3-7 times. Stretching may be performed after the dyeing treatment or may be performed while dyeing. Moreover, you may dye after extending | stretching.

A swelling process, a crosslinking process, a washing process, a drying process, etc. are given to a polyvinyl alcohol-type film as needed. For example, by immersing the polyvinyl alcohol-based film in water prior to dyeing and washing with water, it is possible not only to clean the dirt and the blocking agent on the surface of the polyvinyl alcohol-based film, but also to swell the polyvinyl alcohol-based film to prevent staining and the like. Can be.

As the polarizer layer 2, for example, as described in Japanese Patent Application Laid-Open No. 2016-170368, a dichroic dye may be used in the cured film polymerized with a liquid crystal compound. As a dichroic dye, what has absorption within the range of 380-800 nm can be used, It is preferable to use an organic dye. Examples of the dichroic dyes include azo compounds. A liquid crystal compound is a liquid crystal compound which can superpose | polymerize with orientation, and can have a polymeric group in a molecule | numerator.

It is preferable that it is 95% or more, and, as for the visibility correction polarization degree of the polarizer layer 2, it is more preferable that it is 97% or more. Moreover, 99% or more may be sufficient and 99.9% or more may be sufficient. The visibility correction polarization degree of the polarizer layer 2 may be 99.995% or less, or 99.99% or less.

Here, "visibility correction polarization degree" of the polarizer layer 2 is the value which corrected the polarization degree of the polarizer layer 2 with respect to the light of wavelength λnm with the visibility of the light of wavelength λnm. Hereinafter, "visibility correction polarization degree" may only be called "correction polarization degree."

Corrected polarization degree is corrected by the 2 degree field of view (C light source) of "JIS Z 8701" with respect to the obtained polarization degree using the spectrophotometer ("V7100" by Nippon Bunko Corp.) equipped with an integrating sphere. It can calculate by making it.

If the corrected polarization degree of the polarizer layer 2 is less than 95%, the function as an antireflection film may not be fulfilled.

It is preferable that it is 40% or more, and, as for the visibility correction monolith transmittance of the polarizer layer 2, it is more preferable that it is 42% or more. Moreover, it is preferable that it is 50% or less, and, as for the visibility correction monolith transmittance of the polarizer layer 2, it is more preferable that it is 45% or less. If it is a circularly-polarizing plate provided with the high transmittance polarizer layer, it is easy to visually recognize the coloring of the reflected light made into a subject in this application. Therefore, the circularly polarizing plate provided with the high transmittance polarizer layer and to which the present invention is applied has a high quality that suppresses the reflected light from being colored, compared with the circularly polarizing plate having the high transmittance polarizer layer and to which the present invention is not applied. Can be used as a circularly polarizing plate.

Here, the "visibility correction monolithic transmittance" of an object is the value which corrected the transmittance of the object with respect to the light of wavelength (lambda) nm with the visibility of the light of wavelength (lambda) nm. Hereinafter, "visibility correction monolithic transmittance" may only be called "correction | transmission transmittance".

Corrected transmittance is calculated by performing visibility correction by the 2-degree field of view (C light source) of JIS Z 8701 with respect to the obtained transmittance using a spectrophotometer equipped with an integrating sphere ("V7100" manufactured by Nippon Bunko Co., Ltd.). can do.

Since the polarization degree is too low for the polarizer layer 2 whose correction transmittance | permeability exceeds 50%, the function as an antireflection film may not be able to be achieved.

(Phase difference layer)

The phase difference layer 3 can be a positive A plate which functions as a quarter wave plate (λ / 4 plate).

When the retardation layer 3 has the refractive index in the slow axis direction in the plane nx, the refractive index in the fast axis direction in the plane ny, and the refractive index in the thickness direction is nz, Satisfy the relationship. The retardation layer 3, which is a λ / 4 plate, has a function of converting linearly polarized light of a specific wavelength into circularly polarized light or circularly polarized light into linearly polarized light.

The phase difference layer 3 exhibits any suitable index ellipsoid as long as the relationship of nx> ny is satisfied. Preferably, the index ellipsoid of the retardation layer 3 exhibits a relationship of nx> ny ≧ nz. Nz coefficient of the retardation layer 3 becomes like this. Preferably it is 1-2, More preferably, it is 1-1.5, More preferably, it is 1-1.3.

In addition, the retardation layer 3 exhibits reverse wavelength dispersion characteristics.

In the usual resin film, the ratio of in-plane retardation value Rg to green light and in-plane retardation value Rb to blue light is Rb / Rg, and the ratio of in-plane retardation value Rg and in-plane retardation value Rr to red light is Rr / Rg. When it does, Rr / Rg becomes smaller than Rb / Rg. Hereinafter, such wavelength dispersion may be called "positive" wavelength dispersion.

In contrast, the phase difference layer 3 is larger in Rr / Rg than in Rb / Rg. Regarding the characteristics of such a phase difference layer, since the magnitude relationship of the ratio of in-plane phase difference values reverses with respect to the optical characteristic of a normal resin film, it is called "inverse" wavelength dispersion.

The retardation layer 3 satisfies the following (1) and (2) when the in-plane retardation value with respect to light having a wavelength of λ nm is set to Re (λ).

0.80 <Re (450) / Re (550) <1.00... (One)

1.00 <Re (650) / Re (550) <1.30... (2)

Re (450) / Re (550) in Formula (1) is a value exceeding 0.80, It is preferable that it exceeds 0.82, Re (450) / Re (550) is less than 1.00, It is preferable that it is 0.95 or less, It is more preferable that it is 0.92 or less, It is especially preferable that it is less than 0.90, Re (450) / Re (550) is more than 0.80 and 0.95 or less is preferable, It is more preferable than 0.80 and 0.92 or less, More preferably, 0.82 or more and 0.92 or less Preferably, it may exceed 0.80 and may be less than 0.90.

Re (650) / Re (550) in Formula (2) is less than 1.30, it is preferable that it is 1.20 or less, and it is more preferable that it is 1.10 or less. Re (650) / Re (550) is preferably more than 1.00 and less than 1.20, more preferably more than 1.00 and less than 1.10.

Although the thickness in particular of the phase difference layer 3 is not restrict | limited, 0.5-10 micrometers is preferable and 0.5-5 micrometers is more preferable. In addition, about the thickness of the phase difference layer 3, the thickness of arbitrary 5 points | pieces in surface is measured, and these are the arithmetic mean.

The wavelength dispersion characteristic of such a retardation layer originates in the wavelength dispersion characteristic of the liquid crystal compound which is a raw material of a retardation layer. The wavelength dispersion characteristics of the retardation layer showing the reverse wavelength dispersion characteristics are appropriately adjusted by controlling the mixing ratio of the liquid crystal compound showing the wavelength dispersion of the constant wavelength dispersion and the liquid crystal compound showing the wavelength dispersion of the reverse wavelength dispersion and the thickness of the retardation layer. Can be.

In the phase difference layer of embodiment of Unexamined-Japanese-Patent No. 2017-167517, the balance of the wavelength dispersion characteristic of the short wavelength side and the wavelength dispersion characteristic of the long wavelength side is adjusted based on 550 nm.

By such adjustment, the wavelength dispersion characteristic of the retardation layer 3 approaches an abnormal state on the long wavelength side (red side), and can suppress the coloring of the reflected light in red. At this time, the "ideal state" is a state of the phase difference of the phase difference layer of the abnormal state which converts light of any wavelength into ideal circularly polarized light.

On the other hand, since the wavelength dispersion characteristic of the phase difference layer 3 moves away from an abnormal state on the short wavelength side (blue side) by adjustment as described above, the reflected light tends to be colored blue.

In the circular polarizing plate of the present embodiment, the coloring of the reflected light generated in this manner is reduced by the function of the light absorbing layer described later.

The phase difference layer 3 can be manufactured by a well-known method.

For example, after synthesizing the polymerizable reverse wavelength dispersed liquid crystal by a known method, the reverse wavelength dispersed liquid crystal is coated on the alignment film formed on the substrate, aligned in one direction, and the reverse wavelength dispersed liquid crystal is polymerized to reverse reverse dispersion characteristics. The retardation layer 3 provided with this can be manufactured.

(Protective film)

The protective films 5 and 6 function as a protective layer which protects the polarizer layer 2. In the figure, although the protective films 5 and 6 are arrange | positioned on both surfaces of the polarizer layer 2, the protective film 6 is abbreviate | omitted and the outside of the polarizer layer 2 (a side opposite to the retardation layer 3) It is good also as a structure provided only with the protective film 5 arrange | positioned at the opposite surface). In addition, the protective film 6 may be arrange | positioned at the inner surface (surface of the side facing the phase difference layer 3) of the polarizer layer 2.

As a material of the protective films 5 and 6, for example, a thermoplastic resin having light transparency can be used. The protective films 5 and 6 are, for example, chain polyolefin resins such as polypropylene resins, polyolefin resins such as cyclic polyolefin resins, cellulose triacetate, cellulose ester resins such as cellulose diacetate, polyester resins, Polycarbonate resin, (meth) acrylic resin, polystyrene resin, etc. can be used as a forming material. Norbornene-type resin is mentioned as cyclic polyolefin type resin. These materials may use a mixture, a copolymer, and the like.

In addition, the protective films 5 and 6 may be protective films having optical functions such as retardation layers and brightness enhancement films. For example, the film made of the thermoplastic resin may be uniaxially or biaxially stretched, or a liquid crystal layer or the like may be formed on the film to form a phase difference layer to which an arbitrary retardation value is applied.

In this case, the retardation layer 3 mentioned above can also serve as the protective film 6.

As for the total thickness of the protective films 5 and 6, 5 micrometers-200 micrometers are preferable, More preferably, they are 5 micrometers-100 micrometers, More preferably, they are 10 micrometers-95 micrometers. In the protective films 5 and 6, the total of the in-plane retardation values Re (550) is, for example, 0 nm to 10 nm or 70 nm to 140 nm, and the total of the retardation values Rth (550) in the thickness direction is, for example, -80 nm to +80 nm.

The protective film 5 is a surface treatment such as a hard coat treatment, an antireflection treatment, an anti-sticking treatment, an anti-glare treatment, or the like, on the surface opposite to the side facing the polarizer layer 2 as necessary. May be performed. The thickness of the surface treatment layer is 500 µm or less, preferably 150 µm or less, more preferably 1 µm to 20 µm, still more preferably 2 µm to 10 µm.

In addition, when arrange | positioning the circularly-polarizing plate 1 of this embodiment to the display surface of the passive stereoscopic display apparatus using circularly polarized light, the circularly polarizing plate 1 is the polarizer layer 2 of the protective film 5 It is good also as providing a (lambda) / 4 plate in the surface on the opposite side to the opposite side.

It is preferable that the protective film 6 is optically isotropic. That is, this "optical isotropic" means that the in-plane retardation value Re (550) is 0 nm-10 nm, and the retardation value Rth (550) of the thickness direction is -10 nm-+10 nm. The thickness of the protective film 6 in this case becomes like this. Preferably it is 2 micrometers-200 micrometers, More preferably, it is 5 micrometers-100 micrometers.

(Light absorption layer)

The light absorbing layer 7 has a base material layer and a pigment dispersed in the base material layer.

The base material layer may be an active energy ray curable adhesive containing a curable compound cured by irradiation of active energy rays, or an aqueous adhesive obtained by dissolving or dispersing an adhesive component such as polyvinyl alcohol resin in water. In this case, the light absorption layer 7 functions as an adhesive layer.

The active energy for starting the curing reaction of the active energy ray curable adhesive includes, for example, ultraviolet rays, visible light, electron beams and X-rays. The active energy ray curable adhesive is preferably an ultraviolet curable adhesive.

Since the active energy ray curable adhesive exhibits good adhesion, an active energy ray curable adhesive composition containing any one or both of a cationically polymerizable curable compound and a radically polymerizable curable compound is preferable. The active energy ray curable adhesive may further include either or both of a cationic polymerization initiator and a radical polymerization initiator for starting the curing reaction.

As a cationically polymerizable curable compound, the epoxy type compound which has 1 or 2 or more epoxy groups in a molecule | numerator, the oxetane type compound which has 1 or 2 or more oxetane rings in a molecule | numerator is mentioned, for example.

As a radically polymerizable curable compound, the (meth) acrylic-type compound which has 1 or 2 or more (meth) acryloyloxy groups in a molecule | numerator, and the other vinyl type compound which has a radically polymerizable double bond are mentioned, for example.

Active energy ray-curable adhesives may be, for example, cationic polymerization promoters, ion traps, antioxidants, chain transfer agents, tackifiers, thermoplastic resins, fillers, flow regulators, plasticizers, antifoaming agents, antistatic agents, leveling agents, solvents, and the like. It may contain an additive.

The pigment | dye disperse | distributed to the base material layer of the light absorption layer 7 has maximum absorption wavelength in the wavelength band of wavelength 390-430 nm which is a short wavelength band of visible light. Here, in this embodiment, "visible light" is light of the wavelength contained in the range of 390 nm-830 nm.

As such a pigment | dye, KEMISORB 111, KEMISORB 73 (all are manufactured by Chemiprogase Co., Ltd.), and SUMISORB 300 (made by Sumika ChemteX Co., Ltd.) are mentioned, for example.

In addition, the compound which has the maximum absorption wavelength in the wavelength band of wavelength 390-430 nm can be synthesize | combined by a well-known method, and can be used as a pigment | dye of this embodiment. As such a pigment | dye, the compound known as a light selective absorbing compound of Unexamined-Japanese-Patent No. 2017-120430 can be used, for example.

In the case where the light absorption layer 7 functions as an adhesive layer, the thickness of the light absorption layer 7 is preferably 0.5 to 5 µm, more preferably 0.5 to 3 µm.

In this light absorption layer 7, the dye dispersed in the base layer absorbs blue light. Therefore, the light emitted through the circular polarizing plate 1 can be reduced in blue color.

In addition, the base material layer may be appropriately selected from the pressure-sensitive adhesive exhibiting adhesion performance such that peeling or the like does not occur in a high temperature environment, a moist heat environment, or a high temperature and a low temperature where the polarizing plate is exposed, as a forming material. In this case, the light absorption layer 7 functions as an adhesive layer.

As a formation material of a base material layer, a conventionally known acrylic adhesive, silicone pressure sensitive adhesive, rubber type adhesive, etc. are mentioned. Among them, acrylic pressure-sensitive adhesives are particularly preferred because they have high transparency, weather resistance, excellent heat resistance and easy processing.

In the pressure-sensitive adhesive, as necessary, fillers, plasticizers, glass fibers, glass beads, metal powders, other inorganic powders, fillers, pigments, colorants, fillers, antioxidants, ultraviolet absorbers, antistatic agents, silane coupling agents, etc. And various additives may be appropriately blended.

The light absorption layer 7 which is an adhesive layer is normally formed by apply | coating the solution of an adhesive on a release sheet, and drying it. As the coating on the release sheet, for example, a roll coating method such as reverse coating or gravure coating, a spin coating method, a screen coating method, a fountain coating method, a dipping method, a spray method, or the like can be adopted. The release sheet which provided the adhesive layer is used by the method etc. which transfer this.

The thickness of the light absorption layer 7 which is an adhesive layer is about 3-100 micrometers normally, Preferably it is 5-50 micrometers.

The amount of blue light absorbed by the light absorbing layer 7 can be controlled by adjusting the type of dye, the amount of dye included in the light absorbing layer 7, and the thickness of the light absorbing layer 7. When the amount of the dye contained in the light absorbing layer 7 is increased, the amount of absorption of blue light by the light absorbing layer 7 tends to increase. In addition, when the thickness of the light absorbing layer 7 is increased, the amount of blue light absorbed by the light absorbing layer 7 tends to increase.

The light absorption layer 7 preferably has a transmittance T (λ) satisfying the following (i) to (iii).

T (390) &lt; 85%. (i)

T (410) ≤ 98%. (ii)

T (430) ≤ 99%. (iii)

T 390 is preferably 40% or less, and more preferably 1% or less.

T 410 is preferably 50% or less, and more preferably 10% or less.

T 430 is preferably 90% or less, and more preferably 88% or less.

In this embodiment, the transmittance | permeability of the light absorption layer 7 employ | adopts the value measured by the following method.

One surface of the light absorption layer is bonded to alkali-free glass (manufactured by Corning Corporation, brand name "Eagle XG"), and a cycloolefin-based film (Nippon Xeon Co., Ltd. product) of 23 µm thickness is attached to the other surface of the light absorption layer. `` ZF-14-23 ''). Next, the transmittance | permeability Tb (390) which calculates the transmittance | permeability of 390 nm, 410 nm, and 430 nm of the obtained laminated body using the spectrophotometer ("V7100" by Nippon Bunko Corp.) which has an integrating sphere. ), Tb 410 and Tb 430. In addition, a measured value shall be a value remove | eliminated the influence of interface reflection.

(Circular polarizer)

In the circular polarizing plate 1 of this embodiment, by absorbing blue light in the light absorption layer 7, the transmittance on the short wavelength side is reduced. As a result, the light emitted through the circular polarizing plate 1 of the present embodiment reduces the amount of light on the short wavelength side and reduces the coloration of blue.

In the circular polarizing plate 1 of the present embodiment, the circular polarizing plate 1 of desired physical properties can be easily provided by defining the transmittance of blue light based on the following idea.

First, when a user uses a display device in which an antireflection plate is bonded to a display surface, the reflected light recognized by the user usually includes light of various wavelengths, not light of a single wavelength. The amount of blue light included in the reflected light is the total amount of light of 380 to 450 nm recognized as "blue light".

In addition, the amount of blue light emitted through the circular polarizing plate 1 is "the amount of light of 380-450 nm contained in the light incident on the circular polarizing plate 1" and the "380-450 nm wavelength band of the circular polarizing plate 1". Is the product of transmittance of &quot;

As described above, the circular polarizing plate 1 is a laminate of various functional layers, and the protective films 5 and 6 and the pressure-sensitive adhesive layer 8 are usually colorless and transparent. Therefore, in discussing the color of reflected light, it is thought that the influence of the protective films 5 and 6 and the adhesive layer 8 on the reflected light need not be considered.

In addition, the polarizer layer 2 causes light in the entire wavelength band to be transmitted or absorbed or reflected.

From this, the structure which has a strong influence on the color of the reflected light in the circular polarizing plate 1 can be judged as the phase difference layer 3 and the light absorption layer 7.

In the circular polarizing plate 1 of the present embodiment, the integrated value of the transmittance of the phase difference layer 3 in the wavelength band of 380 to 450 nm and the light absorbing layer 7 in the wavelength band of 380 to 450 nm. The sum total value (total integrated value) of the integrated value of the transmittance | permeability of () is 5000 or less. In the circularly polarizing plate 1 in which the phase difference layer 3 and the light absorbing layer 7 which have a strong influence on the color of the reflected light exhibit such a value, the blue light included in the reflected light is reduced well and the reflected light is colored. It becomes possible to suppress it.

In the present embodiment, the "integrated value of the transmittance" of the retardation layer 3 and the light absorption layer 7 is a transmittance with respect to light having a different wavelength every 2 nm in a wavelength band of 380 to 450 nm. It measures and points to the value which accumulated the measured value of each transmittance.

It is preferable that the said total integrated value is 4000 or less, It is more preferable that it is 3000 or less, It is especially preferable that it is 2800 or less.

As described above, the circularly polarizing plate 1 uses a reverse wavelength dispersion type phase difference layer in which optical characteristics are adjusted as the phase difference layer 3. Therefore, in the circular polarizing plate 1, the leakage light of red light is reduced and the leakage light of blue light increases. That is, the circular polarizing plate 1 has a structure in which reflected light tends to be blue when considering the configuration of the phase difference layer 3.

Here, the circular polarizing plate 1 is configured to be able to absorb blue light satisfactorily in the light absorption layer 7. In addition, in the circular polarizing plate 1, the total integrated value of the transmittance | permeability in the wavelength band of wavelength 380-450 nm is 5000 or less with respect to the retardation layer 3 and the light absorption layer 7, and the blue light is made to permeate | transmit blue light. It is difficult.

Therefore, in the circular polarizing plate 1, the light absorption layer 7 absorbs the blue light contained in the reflected light favorably, and it can suppress that the reflected light is colored.

(Optical display panel)

Examples of the optical display panel 20 include a liquid crystal display device and an organic EL panel. As a liquid crystal display device and an organic electroluminescent panel, the thing with a normally known structure can be used.

As shown in FIG. 1, the circular polarizing plate 1 described above is bonded to the display surface of the optical display panel 20 to constitute the optical display device 10. By providing the circular polarizing plate 1 on the display surface, the optical display device 10 suppresses reflection of external light and suppresses reflection of reflected light.

According to the circularly polarizing plate 1 of the above structure, it becomes a circularly polarizing plate which suppressed coloring of reflected light.

Moreover, according to the optical display device 10 of the above structure, favorable image display is attained.

In addition, in the circular polarizing plate 1 of this embodiment, although having the phase difference layer 3 which is a positive A plate, you may use positive C plate together.

The positive C plate satisfies the relationship of nz> nx ≧ ny. The difference between the value of nx and the value of ny is preferably within 0.5% of the value of ny, and more preferably within 0.3%. If it is within 0.5%, it can be considered that nx = ny substantially.

In the positive C plate, it is preferable that the phase difference value Rth (λ) in the thickness direction at the wavelength λnm satisfies the relationship of -300 nm≤Rth (550) ≤-20 nm, and -150 nm≤Rth (550) It is more preferable to satisfy the relationship of? -20 nm.

Such a positive C plate may be provided between the polarizer layer 2 and the optical display panel 20.

In addition, in this embodiment, although the pigment | dye disperse | distributes to the adhesive bond layer or adhesive layer which integrates the polarizer layer 2 and the retardation layer 3, and functions as the light absorption layer 7, it is not limited to this.

The pigment | dye which absorbs blue light may be disperse | distributed to another layer, unless the effect of invention is impaired. For example, when the pigment | dye mentioned above is mixed in the adhesive layer 8, the adhesive layer 8 turns into the light absorption layer in this invention.

In addition, the pigment | dye may be disperse | distributed to the protective films 5 and 6, and may function as a light absorption layer.

In this case, the base material layer which a light absorption layer has can be made into the film which shape | molded the thermoplastic resin. As a light absorption layer which has such a base material layer, arbitrary films arrange | positioned at the visual recognition side of a display element, such as a protective film, may be sufficient.

As a light absorption layer, it is preferable that it is a light absorption layer in which the pigment | dye was disperse | distributed in these base material layers using the adhesive layer and adhesive bond layer which can be manufactured on relatively mild conditions.

Only one layer may be sufficient as a light absorption layer, and two or more layers may be provided.

It is explanatory drawing which shows the modification of an optical display device.

The optical display device 100 includes a circular polarizing plate 30 having a front plate, a touch sensor 40, and an optical display panel 20. As shown in the figure, in the optical display device 100, the circularly polarizing plate 30 having the front plate, the touch sensor 40, and the optical display panel 20 can be stacked on each other.

In the optical display device 100, in the circular polarizing plate 1, the polarizer layer 2 is disposed on the outer side, that is, opposite to the optical display panel 20, and the phase difference layer 3 is on the optical display panel 20 side. Is placed on. In other words, in the optical display device 100, the circularly polarizing plate 1 is disposed such that the phase difference layer 3 is positioned between the polarizer layer 2 and the optical display panel 20.

The circular polarizing plate 30 having the front plate includes the circular polarizing plate 1 described above and a front plate (window film) 35 provided in contact with the protective film 5 included in the circular polarizing plate 1. That is, the circularly polarizing plate 30 having the front plate has a configuration in which the front plate (window film) 35 and the polarizing plate 1 are stacked. The polarizing plate 30 having this front plate has a front plate 35 on the polarizer layer 2 side constituting the polarizing plate 1.

(Front panel)

The front plate 35 has a transparent base material 31 and a hard coat layer 32 formed on at least one surface of the transparent base material 31. The front plate 35 has a function of protecting the components of the optical display panel 20 and the other optical display device 10 from internal stress caused by external impact or changes in temperature and humidity. As for the front plate 35 shown in the figure, the transparent base material 31 side is provided in contact with the protective film 5.

The transparent base material 31 can employ | adopt various things, if it is a flexible resin film which has light transparency. In addition, in this specification, "transparence" means that the transmittance | permeability of visible light is 70% or more or 80% or more.

As the transparent base material 31, the unstretched film, uniaxial stretched film, or biaxially stretched film of various transparent resins can be used. Only 1 type may be used for the transparent resin which comprises the transparent base material 31, and 2 or more types may be mixed and used for it.

As such a transparent base material 31, a polyamideimide film, a polyimide film, a stretched polyester film, a cycloolefin derivative film, a polymethyl methacrylate film, a triacetyl cellulose, or an isobutyl ester cellulose film is specifically preferable. .

5 micrometers-200 micrometers are preferable and, as for the thickness of the transparent base material 31, 20 micrometers-100 micrometers are more preferable.

The hard coat layer 32 has a function of improving the surface hardness of the transparent base material 31. In addition, the hard coat layer 32 is provided with light transmittance and flexibility.

The hard coat layer 32 can be formed by hardening the hard coat composition containing a photocurable (meth) acrylate monomer or oligomer, a photocurable epoxy monomer, an oligomer, etc. as a formation material.

In addition to the monomer and oligomer mentioned above, a hard coat composition contains a solvent and a photoinitiator as needed. The hard coat composition may also contain additives such as inorganic fillers, leveling agents, stabilizers, antioxidants, UV absorbers, surfactants, lubricants, and antifouling agents within a range that does not impair the effects of the invention.

The hard coat layer 32 can be formed by apply | coating the hard coat composition mentioned above to at least one surface of the transparent base material 31, and hardening.

Although the thickness of the hard-coat layer 32 is not specifically limited, 5 micrometers-100 micrometers are preferable. If the thickness of the hard coat layer 32 is 5 micrometers or more, sufficient impact resistance can be ensured. Moreover, if the thickness of the hard-coat layer 32 is 100 micrometers or less, it will become the hard-coat layer 32 which has sufficient flexibility practically. In addition, curling by hardening and shrinkage of the hard coat composition is unlikely to occur when the hard coat layer 32 is formed.

(Touch sensor)

The optical display device 100 shown in FIG. 3 includes a touch sensor 40 between the display surface of the optical display panel 20 and the circular polarizing plate 1. The touch sensor 40 includes a base 41, a lower electrode 42 provided on the base 41, an upper electrode 43 facing the lower electrode 42, a lower electrode 42, and an upper electrode 43. ) And an insulating layer 44 sandwiched between the layers. The touch sensor 40 shown in the figure is a so-called projected capacitive touch sensor.

The touch sensor 40 shown in the figure has the front plate in a state where the base 41 faces the optical display panel 20 and the upper electrode 43 faces the circular polarizing plate 30 having the front plate. The circularly polarizing plate 30 and the optical display panel 20 are sandwiched.

The base material 41 can employ | adopt various things, if it is a flexible resin film which has light transmittance. For example, the film illustrated as the material of the above-mentioned transparent base material 31 can be used as the base material 41.

The lower electrode 42 has, for example, a plurality of square small electrodes in plan view. The plurality of small electrodes 42a are arranged in a matrix.

Further, the plurality of small electrodes 42a are connected to the small electrodes 42a adjacent to one diagonal direction of the small electrode 42a to form a plurality of electrode rows. The plurality of electrode rows are connected to each other at the end, so that the capacitance between neighboring electrode rows can be detected.

The upper electrode 43 has, for example, a plurality of square small electrodes in plan view. The plurality of small electrodes 43a are arranged in a matrix complementary to positions where the lower electrodes 42 are not arranged in plan view. That is, the upper electrode 43 and the lower electrode 42 are arranged without a gap in plan view.

The plurality of small electrodes 43a are connected to the small electrodes 43a adjacent to the other diagonal direction of the small electrode 43a to form a plurality of electrode rows. The plurality of electrode rows are connected to each other at the end, so that the capacitance between neighboring electrode rows can be detected.

The insulating layer 44 insulates the lower electrode 42 and the upper electrode 43 from each other. As a material for forming the insulating layer 44, a material commonly known as a material for the insulating layer of the touch panel can be used.

In the present embodiment, the touch sensor 40 has been described as being a so-called projected capacitive touch sensor. However, a touch sensor of another method, such as a film resistance method, may be employed within a range that does not impair the effects of the invention. It may be.

Each layer (front plate, circular polarizing plate, and touch sensor) forming the optical display device can be laminated by an adhesive. Examples of the adhesive include an aqueous adhesive, an organic solvent, a solvent-free adhesive, a solid adhesive, a solvent volatilized adhesive, a moisture curable adhesive, a heat curable adhesive, an anaerobic curing type, an active energy ray curable adhesive, a curing agent mixed adhesive, a hot melt adhesive, and a pressure sensitive type. What is used universally can be used, such as an adhesive agent (adhesive) and a wet type adhesive agent. Among them, an aqueous solvent volatilized adhesive, an active energy ray curable adhesive, and an adhesive are often used. The thickness of an adhesive bond layer can be adjusted suitably according to the adhesive force etc. which are requested | required, and are 0.01 micrometer-500 micrometers, Preferably they are 0.1 micrometer-300 micrometers. Although there exist multiple in the said laminated body for flexible image display apparatuses, each kind of thickness may be same or different.

As the aqueous solvent volatilized adhesive, a polymer in an aqueous dispersion state such as a polyvinyl alcohol polymer, a water-soluble polymer such as starch, an ethylene-vinyl acetate emulsion, or a styrene-butadiene emulsion can be used as the main polymer. In addition to water and the said main agent polymer, you may mix | blend a crosslinking agent, a silane type compound, an ionic compound, a crosslinking catalyst, antioxidant, dye, a pigment, an inorganic filler, an organic solvent, etc.

In the case of adhering with the aqueous solvent volatilized adhesive, the aqueous solvent volatilized adhesive may be injected between the adherend layers to bond the adherend layer, and then adhesiveness may be imparted by drying. The thickness of the adhesive layer in the case of using the said aqueous solvent volatilization adhesive agent may be 0.01-10 micrometers, Preferably 0.1 micrometer-1 micrometer may be sufficient. When using multiple layers of the above-mentioned aqueous solvent volatilized adhesive, the thickness of each layer may be the same or different.

The said active energy ray hardening-type adhesive agent contains the reactive material which irradiates an active energy ray and forms an adhesive bond layer. When using the said active energy ray hardening-type adhesive agent, an adhesive bond layer can be formed by hardening of an active energy ray hardening composition. The active energy ray-curing composition may contain at least one polymer of a radically polymerizable compound and a cationically polymerizable compound such as a hard coat composition. The said radically polymerizable compound is the same as that of a hard coat composition, The thing of the same kind as a hard coat composition can be used. As a radically polymerizable compound used for an adhesive bond layer, the compound which has an acryloyl group is preferable. In order to lower the viscosity as an adhesive composition, it is also preferable that the said active energy ray hardening-type adhesive agent contains a monofunctional compound.

The said cationically polymerizable compound is the same as that of a hard coat composition, The thing of the same kind as a hard coat composition can be used. As a cationically polymerizable compound used for an active energy ray hardening composition, an epoxy compound is especially preferable. In order to reduce the viscosity as an adhesive composition, it is also preferable that the said cationically polymerizable compound contains a monofunctional compound as a reactive diluent.

The active energy ray curing composition may further include a polymerization initiator. As a polymerization initiator, it is a radical polymerization initiator, a cationic polymerization initiator, a radical, and a cationic polymerization initiator, etc., It can select suitably and can use. These polymerization initiators are decomposed by at least one of active energy ray irradiation and heating to generate radicals or cations to advance radical polymerization and cationic polymerization. As a polymerization initiator, the initiator used for the active energy ray curable adhesive shown by the base material regarding the light absorption layer mentioned above can be used.

The active energy ray curing composition may further include an ion trapping agent, an antioxidant, a chain transfer agent, an adhesion agent, a thermoplastic resin, a filler, a flow viscosity modifier, a plasticizer, an antifoaming agent, an additive, and a solvent. In the case of adhering with the active energy ray-curable adhesive, the active energy ray-curing composition is applied to any one or both of the layers to be bonded and bonded, and the active energy rays are irradiated and cured through any one of the layers or both layers. It can adhere | attach by making it.

The thickness of the adhesive layer in the case of using the said active energy ray hardening-type adhesive agent may be 0.01 micrometer-20 micrometers, Preferably 0.1 micrometer-10 micrometers may be sufficient. When using two or more layers of the said active energy ray hardening-type adhesive agents, the kind of thickness of each layer may be same or different.

As the pressure-sensitive adhesive (adhesive), any one classified into an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, a rubber pressure-sensitive adhesive, a silicone pressure-sensitive adhesive, or the like may be used depending on the main polymer. In addition to the main agent polymer, the pressure-sensitive adhesive may contain a crosslinking agent, a silane compound, an ionic compound, a crosslinking catalyst, an antioxidant, a tackifier, a plasticizer, a dye, a pigment, an inorganic filler, and the like. An adhesive bond layer (adhesive layer) is formed by dissolving and disperse | distributing each component which comprises the said adhesive in a solvent, obtaining an adhesive composition, and apply | coating this adhesive composition on a base material, and drying. The pressure-sensitive adhesive layer may be directly formed, or may be transferred to what is formed on the substrate separately. In order to cover the adhesive surface before adhesion, it is also preferable to use a release film.

In the case of using the pressure-sensitive adhesive (adhesive), the thickness of the adhesive layer (adhesive layer) may be 0.1 µm to 500 µm, preferably 1 µm to 300 µm. When using more than one layer of the said adhesive, the thickness of each layer may be same or different.

Even in the optical display device 100 having the above-described configuration, the reflected light is suppressed from being colored, so that good image display is possible.

As mentioned above, although the example of suitable embodiment which concerns on this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this example. Various shapes, combinations, and the like of the respective structural members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the spirit of the present invention.

EXAMPLE

Although an Example demonstrates this invention below, this invention is not limited to these Examples.

(Example 1)

In the Example, the total integrated value and the reflection color were measured about the sample produced respectively by the following method.

<1. Measurement of Total Integration Value>

(Production of phase difference layer)

(Production of reverse wavelength dispersion liquid crystal)

5 mass parts (mass average molecular weight: 30000) of the photo-alignment material represented by following formula (11), and 95 mass parts of cyclopentanone which are solvents were mixed, and the obtained mixture was stirred at 80 degreeC for 1 hour, and the composition for orientation film formation was obtained. .

Moreover, the mixture which mixed the polymeric liquid crystal compound A represented by following formula (12) and the polymeric liquid crystal compound B represented by following formula (13) by the mass ratio of 90:10 was prepared.

The polymeric liquid crystal compound A was manufactured by the method of Unexamined-Japanese-Patent No. 2010-31223. In addition, polymeric liquid crystal compound B was manufactured according to the method of Unexamined-Japanese-Patent No. 2009-173893.

[Polymerizable Liquid Crystal Compound A]

[Polymerizable Liquid Crystal Compound B]

1.0 mass part of leveling agents (DIC Corporation make, brand name "F-556") and the polymerization initiator 2-dimethylamino-2-benzyl-1- (4-morpholinophenyl) butane-1 which are obtained to the obtained mixture. 6 parts by mass of -ON (BASF Japan Co., Ltd. make, brand name "Irgacure® 369 (Irg369)") was added.

Furthermore, the composition for liquid crystal cured film formation was obtained by adding N-methyl- 2-pyrrolidone (NMP) so that solid content concentration might be 13 mass%, and stirring at 80 degreeC for 1 hour.

As a base material, the 50 micrometer-thick cycloolefin type film (made by Nippon Zeon Co., Ltd., brand name "ZF-14-50") was prepared.

After performing a corona treatment to a base material, the composition for aligning film formation was apply | coated to the surface which performed the corona treatment with a bar coater, it dried for 1 minute at 80 degreeC, and a polarizing UV irradiation apparatus (made by Ushio Denki Co., Ltd., brand name "SPOT CURE" SP-9 "), the polarized light UV exposure was performed by the accumulated light quantity in wavelength 313nm: 100mJ / cm <2>, the axial angle of 45 degree, and the orientation film was formed.

Next, the composition for liquid crystal cured film formation was apply | coated to the oriented film using the bar coater, and it dried at 120 degreeC for 1 minute.

Then, the ultraviolet-ray was irradiated to the coating film of the composition for liquid crystal cured film formation using the high pressure mercury lamp (made by Ushio Denki Co., Ltd., brand name: "Unicure VB-15201 BY-A"). The irradiation conditions of ultraviolet-ray were 500 mJ / cm <2> of accumulated light amounts in wavelength 365nm in nitrogen atmosphere.

Thereby, the liquid crystal cured film was formed and the laminated body by which the base material, the orientation film, and the liquid crystal cured film were laminated | stacked was obtained. The laminated body of an orientation film and a liquid crystal cured film corresponds to the "phase difference layer" in this invention.

The laminated body produced by the said method was bonded to glass through the adhesive layer. The surface which contact | connected the adhesive layer was made into the liquid crystal cured film. The cycloolefin type film which is a base material was peeled from the laminated body, and the sample for retardation value measurement was obtained.

The in-plane phase difference value Re ((lambda)) of the obtained retardation layer was measured with the measuring device (Ojige Seiki Co., Ltd. make, brand name "KOBRA-WPR").

The result of having measured the phase difference value Re ((lambda)) in each wavelength was Re (450) = 121 nm, Re (550) = 142 nm, and Re (650) = 146 nm. Re (450) / Re (550) = 0.85 and Re (650) / Re (550) = 1.03.

FIG. 2 is a graph showing the ratio of the phase difference of light of different wavelengths to the phase difference of light having a wavelength of 550 nm in the obtained phase difference layer. In FIG. 2, the horizontal axis represents wavelength (unit: nm), and the vertical axis represents ratio (unit: dimensionless) of the phase difference of the light of another wavelength with respect to the phase difference of the light of wavelength 550nm. In addition, the line shown by code | symbol S1 in a figure is a line which shows the phase difference of the phase difference layer of the abnormal state which converts the light of any wavelength into ideal circular polarization. Such a line is called "ideal curve".

(Preparation of the pressure-sensitive adhesive composition in which color is mixed)

(Preparation of acrylic resin)

In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer, and a stirrer, 81.8 parts by mass of ethyl acetate as a solvent, 70.4 parts by mass of butyl acrylate, 20.0 parts by mass of methyl acrylate, 8.0 parts by mass of 2-phenoxyethyl acrylate, and acrylic acid 2 -A mixed solution of 1.0 parts by mass of hydroxyethyl and 0.6 parts by mass of acrylic acid was added.

The inside of the reaction vessel was replaced with a nitrogen atmosphere, and the internal temperature of the reaction vessel was raised to 55 ° C. Separately, a solution prepared by dissolving 0.14 parts by mass of azobisisobutyronitrile as a polymerization initiator in 10 parts by mass of ethyl acetate was prepared, and the total amount of the polymerization initiator solution was added to a reaction vessel having an internal temperature of 55 ° C. It maintained at this temperature for 1 hour after initiator addition.

Subsequently, ethyl acetate was continuously added to the reaction vessel at an addition rate of 17.3 parts by mass while maintaining the internal temperature at 54 to 56 ° C. The addition of ethyl acetate was stopped when the concentration of the polymer obtained was 35% by mass.

After warming at 54-56 degreeC from the start of addition of ethyl acetate to 12 hours, ethyl acetate was added and it adjusted so that the polymer concentration might be 20 mass%, and the target acrylic resin was obtained.

(Synthesis of color)

The compound represented by following formula (14) was made into the inside of a 100 mL 4-necked flask equipped with the Dimroth cooling tube and the thermometer in nitrogen atmosphere, and referring the synthesis example of Unexamined-Japanese-Patent No. 2017-120430. Hereinafter, compound (14)) was synthesized.

2.0 g of powder of the obtained compound (14), 1.2 g of triethylene glycol monomethyl ether (made by Tokyo Kasei Kogyo Co., Ltd.), N, N-dimethyl-4-aminopyridine (made by Tokyo Kasei Kogyo Co., Ltd.) ) 20 mg and 8 g of chloroform were placed in a reaction vessel, stirred with a magnetic stirrer, and cooled to an internal temperature of 0 ° C. in an ice bath.

A solution obtained by dissolving 1.4 g of 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride (manufactured by Tokyo Chemical Industry Co., Ltd.) in 2.0 g of chloroform was prepared. The prepared solution was dripped over 2 hours using the dropping funnel in the said reaction container hold | maintained at 0 degreeC of internal temperature. After completion of dropwise addition, the mixture was kept at 0 ° C for 6 hours.

After the reaction was completed, chloroform was removed using an evaporator. The obtained oily substance was dissolved in ethyl acetate, the liquid was separated and washed with 10% dilute sulfuric acid, and then the ethyl acetate solution was separated and washed with pure water until the aqueous layer pH was> 6.

The organic layer after washing | cleaning was dried with forget-me-not, and after removing a forget-me-not, the ethyl acetate was removed by the evaporator, and the pigment | dye represented by following formula (15) (following compound (15)) was obtained.

(Preparation of the pressure-sensitive adhesive composition in which color is mixed)

0.5 mass part crosslinking agent (made by Tosoh Corporation, brand name "colonate") with respect to 100 mass parts of solid content of synthesize | combined acrylic resin, 0.5 mass part 3-glycidoxy propyl trimethoxysilane (Shin-Etsu Chemical Co., Ltd.) Shiki Corporation make, brand name "KBM-403"), and 3.5 mass parts of compound (15) were mix | blended. Moreover, 2-butanone was added so that solid content concentration might be 14 mass%.

The obtained composition was stirred and mixed for 30 minutes at 300 rpm using the stirrer (the Yamato Chemical Co., Ltd. make, brand name "Three one motor"), and the adhesive composition which mix | blended the pigment | dye (compound (15)) was prepared.

(Production of the pressure-sensitive adhesive sheet containing the color)

On the surface of the release process of the polyethylene terephthalate film (Lintec Co., Ltd. make, brand name "SP-PLR382050") to which the mold release process was performed, the above-mentioned adhesive is dried using an applicator so that the thickness of the adhesive layer may be 20 micrometers. Applied. It dried at 100 degreeC for 1 minute, and produced the adhesive sheet which mix | blended the pigment | dye.

One surface of the obtained pressure sensitive adhesive sheet is bonded to an alkali-free glass (manufactured by Corning Corporation, brand name "Eagle XG"), and a cycloolefin-based film (Nippon Xeon Co., Ltd. product) of 23 µm thickness is formed on the other surface of the pressure sensitive adhesive sheet, Trade name "ZF-14-23"). Next, the transmittance | permeability of 390 nm, 410 nm, and 430 nm of the obtained laminated body was measured using the spectrophotometer ("V7100" by the Nippon Bunko Corporation) with an integrating sphere.

About the obtained laminated body, the transmittance | permeability which removed the influence of interface reflection was as follows.

T (390) ≤0.001%

T (410) ≤0.8%

T (430) ≤83.0%

[Production of Laminate with Double-sided Adhesive Layer]

The adhesive sheet mentioned above was bonded on the liquid crystal cured film in the laminated body in which the base material, the orientation film, and the liquid crystal cured film were laminated | stacked.

Subsequently, after peeling off the cycloolefin type film which is a base material, the acrylic adhesive (Rintec Co., Ltd. make, brand name "P-3132") whose thickness is 25 micrometers is bonded to the exposed orientation film, and the laminated body which has a double-sided adhesive layer. Got.

The laminated body which has a double-sided adhesive layer had the laminated constitution of the adhesive layer which mix | blended a pigment | dye, a liquid crystal cured film, an orientation film, and an adhesive layer.

[Measurement of transmittance]

Through an adhesive layer, the laminated body which has a double-sided adhesive layer was bonded to the alkali free glass [The Corning company brand name "Eagle XG"]. Next, the polyethylene terephthalate film (release sheet) on the adhesive layer which mix | blended the pigment | dye was peeled off, and it was set as the sample for transmittance measurement.

The transmittance | permeability of each wavelength was measured for every 2 nm using the ultraviolet visible near-infrared spectrophotometer (The Nippon Bunko Corporation make, brand name "V-7100"). The transmittance | permeability of the sample was measured over the wavelength range of 380 nm-450 nm, and each transmittance was integrated. The integrated value (total integrated value) of the transmittance of the sample was 2770.

<2. Measurement of Reflective Color>

(Production of polarizer)

The polyvinyl alcohol film (average degree of polymerization of about 2400 and saponification degree of 99.9 mol% or more) was uniaxially stretched by about 5 times by dry stretching, and immersed in pure water at 60 ° C. for 1 minute while maintaining a tension state. Then, it was immersed for 60 second in 28 degreeC aqueous solution whose mass ratio of iodine / potassium iodide / water is 0.05 / 5/100.

Subsequently, it immersed for 300 second in 72 degreeC aqueous solution whose mass ratio of potassium iodide / boric acid / water is 8.5 / 8.5 / 100.

Subsequently, after wash | cleaning for 20 second with the pure water of 26 degreeC, it dried at 65 degreeC and obtained the polarizer of thickness 12micrometer.

The produced polarizer had iodine adsorbed to the polyvinyl alcohol film.

(Preparation of Water-based Adhesive)

3 parts by mass of carboxyl group-modified polyvinyl alcohol (manufactured by Co., Ltd., product name "KL-318") is dissolved with respect to 100 parts of water, and the polyamide epoxy clock additive (Daoka Kagaku Kogyo Co., Ltd.) which is a water-soluble epoxy resin in the obtained aqueous solution. 1.5 mass parts of make, brand name "Sumirez resin 650 (30)" and 30% of solid content concentration) were added, and the water-based adhesive agent was prepared.

(Production of polarizing plate)

The above-mentioned water-based adhesive agent was apply | coated to one surface of the obtained polarizer, and the norbornene-type resin film (The Nippon Seishi KK make, brand name "COP25ST-HC", hereafter HC-COP) which had a hard-coat layer was bonded together. .

The used HC-COP is a film in which the hard-coat resin which is 3 micrometers in thickness was formed in the stretched film which consists of cycloolefin resin of thickness 25 micrometers.

The above-mentioned water-based adhesive agent is apply | coated to the other surface of a polarizer, the triacetyl cellulose-type resin film (Fuji Film Co., Ltd. make, brand name "ZRG20SL", hereinafter, TAC) is bonded together, and a polarizing plate is produced. did.

The visibility correction monolith transmittance of the obtained polarizing plate was 45%.

(Production of circularly polarizing plate)

On the triacetyl cellulose-type resin protective film of a polarizing plate, the laminated body which has a double-sided adhesive layer was bonded together through the above-mentioned adhesive sheet, and the circular polarizing plate was produced.

[Measurement of Reflective Colors]

The circularly polarizing plate was bonded to the display surface of OLED display element (The Samsung Electronics Co., Ltd. make, brand name "Galaxy-Tab S8.4") through the adhesive layer. In the non-lighting state, the reflection color b * was measured using a spectrophotometer (manufactured by Konica Minolta Co., Ltd., product name "CM-2600d").

[Visually evaluate the appearance]

The appearance of the sample produced by the measurement of the reflection color was visually confirmed and observed. Evaluation criteria are as follows. The sample evaluated by "(circle)" and "(circle)" was made into good products, and the sample evaluated by "x" was judged as defective goods.

(Evaluation standard)

◎: black

○: slightly blue but black

×: blue

(Example 2)

At the time of preparation of an adhesive composition, the laminated body and circularly-polarizing plate which have a double-sided adhesive layer were produced like Example 1 except having made the addition amount of the compound (15) into 2.5 mass parts. The transmittance | permeability of the adhesive layer measured by the method similar to Example 1 was as follows.

T (390) ≤0.001%

T (410) ≤3.2%

T (430) ≤86.9%

(Example 3)

At the time of preparation of an adhesive composition, the laminated circular polarizing plate which has a double-sided adhesive layer was produced like Example 1 except having made the addition amount of the compound (15) into 1.0 mass part. The transmittance | permeability of the adhesive layer measured by the method similar to Example 1 was as follows.

T (390) ≤0.01%

T (410) ≤3.2%

T (430) ≤95.0%

(Example 4)

At the time of preparation of an adhesive composition, the laminated circular polarizing plate which has a double-sided adhesive layer was produced like Example 1 except having made the addition amount of the compound (15) into 0.02 mass part. The transmittance | permeability of the adhesive layer measured by the method similar to Example 1 was as follows.

T (390) ≤81.9%

T (410) ≤97.2%

T (430) ≤99.0%

(Example 5)

At the time of preparation of an adhesive composition, the laminated circular polarizing plate which has a double-sided adhesive layer was produced like Example 1 except having made the addition amount of the compound (15) into 0.035 mass part. The used acrylic adhesive did not contain the pigment | dye (compound (15)). The transmittance | permeability of the adhesive layer measured by the method similar to Example 1 was as follows.

T (390) ≤70.5%

T (410) ≤95.2%

T (430) ≤98.0%

(Comparative Example 1)

A laminated circular polarizing plate having a double-sided pressure-sensitive adhesive layer was produced in the same manner as in Example 1 except that the light-selective absorbent pressure-sensitive adhesive sheet was changed to an acrylic pressure-sensitive adhesive having a thickness of 5 μm (manufactured by Lintec Corporation, trade name "# L2"). did.

One side of the used 5 micrometer-thick acrylic adhesive (Lintec Co., Ltd. brand name "# L2") was bonded to the alkali-free glass (The Corning company make, brand name "Eagle XG") adhesive, and the other of the acrylic adhesive 23 micrometers thick cycloolefin type film (made by Nippon Zeon Co., Ltd., brand name "ZF-14-23") was bonded to the surface. The transmittance | permeability of 390 nm, 410 nm, and 430 nm of the obtained laminated body was measured in the same manner as in Example using the spectrophotometer provided with an integrating sphere. The transmittance | permeability of an acrylic adhesive was as follows.

T (390) ≤99.9%

T (410) ≤99.9%

T (430) ≤99.9%

The evaluation results are shown in Table 1.

As a result of the evaluation, it was found that each of the circularly polarizing plates of Examples 1 to 5 had a reflection color b * of close to 0 and reduced blue color as compared with the circularly polarizing plate of Comparative Example 1.

As mentioned above, it turned out that this invention is useful.

2: polarizer layer, 3: retardation layer, 7: light absorbing layer, 8: pressure-sensitive adhesive layer, 10: optical display device, 20: optical display panel

Claims (6)

A polarizer layer,
Phase difference layer,
Equipped with a light absorption layer,
The said phase difference layer satisfies following formula (1) and formula (2), when making in-plane phase difference value with respect to the light of wavelength (lambda) nm to Re ((lambda)),
The light absorbing layer has a base layer and a pigment dispersed in the base layer,
The dye has a maximum absorption wavelength in the wavelength band of 390 to 430 nm,
The circularly polarizing plate whose total value of the integrated value of the transmittance | permeability of the said retardation layer in the wavelength band of wavelength 380-450 nm, and the integrated value of the transmittance | permeability of the said light absorption layer in the wavelength band of wavelength 380-450 nm is 5000 or less:
0.80 <Re (450) / Re (550) <1.00... (One)
1.00 <Re (650) / Re (550) <1.30... (2). The circularly polarizing plate of claim 1, wherein the base layer is an adhesive layer or an adhesive layer. The circularly polarizing plate according to claim 1 or 2, wherein the transmittance T (λ) of the light absorption layer with respect to light having a wavelength of λnm satisfies the following formulas (i) to (iii):
T (390) &lt; 85%. (i)
T (410) ≤ 98%. (ii)
T (430) ≤ 99%. (iii). Optical display panel,
An optical display device having the circularly polarizing plate according to any one of claims 1 to 3 bonded to a display surface of the optical display panel. The polarizing plate according to claim 4, wherein the polarizer layer is disposed so that the polarizer layer is opposite to the optical display panel with respect to the phase difference layer.
An optical display device comprising a front plate on the polarizer layer side of the circular polarizing plate. The optical display device according to claim 5, further comprising a touch sensor between the display surface and the circular polarizing plate.

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