TW202404815A - Optical laminate - Google Patents

Abstract

An object of the present invention is to provide an optical laminate having a liquid crystal polarizer and a liquid crystal retardation layer formed using a polymerizable liquid crystal compound realizes excellent wet heat durability. The optical laminate comprises a protective layer, a liquid crystal polarizer, a first bonding layer, a first liquid crystal retardation layer, a second bonding layer, a second liquid crystal retardation layer, and a third bonding layer in this order. The liquid crystal polarizer comprises a cured product layer of a first liquid crystal composition containing a dichroic dye and a polymerizable liquid crystal compound. The first bonding layer is a cured product layer of an active energy ray curable composition. Each of the first liquid crystal retardation layer and the second liquid crystal retardation layer comprises a cured product layer of a second liquid crystal composition containing a polymerizable liquid crystal compound. The glass transition temperatures of the second bonding layer and the third bonding layer are both 25 DEG C or lower.

Description

optical laminate

The present invention relates to an optical laminate.

As an organic EL display device, a flexible display device in which a display screen can be bent or rolled is known. In order to suppress external light reflection, a circularly polarizing plate in which a polarizing element and a phase difference element are laminated can be used in an organic EL display device. Circular polarizing plates applied to flexible display devices are required to reduce the degradation of optical characteristics at bends and to be less likely to cause cracks due to bending (for example, Patent Document 1, etc.).

[Prior technical literature]

[Patent Document]

[Patent Document 1] International Publication No. 2016/158300

When the circular polarizing plate is made thinner, the thickness of the organic EL display device can be reduced, and the bendability of the organic EL display device can be easily improved. Therefore, as the polarizing element constituting the circular polarizing plate For components and retardation elements, there are cases where the circular polarizing plate is thinned by using a liquid crystal polarizer and a liquid crystal retardation layer formed by replacing the resin film with a liquid crystal compound. However, when a circularly polarizing plate equipped with a liquid crystal polarizer and a liquid crystal retardation layer is exposed to a hot and humid environment, island-like unevenness (shading) may be recognized in the circularly polarizing plate.

An object of the present invention is to achieve excellent heat and moisture resistance in an optical laminate including a liquid crystal polarizer and a liquid crystal retardation layer formed using a polymerizable liquid crystal compound.

The present invention provides the following optical laminate.

[1] An optical laminate including a protective layer, a liquid crystal polarizer, a first bonding layer, a first liquid crystal retardation layer, a second bonding layer, a second liquid crystal retardation layer, and a third bonding layer in this order layer, where,

The aforementioned liquid crystal polarizing element includes a cured material layer of a first liquid crystal composition, and the cured material layer of the first liquid crystal composition contains a dichroic dye and a polymerizable liquid crystal compound,

The first liquid crystal retardation layer and the second liquid crystal retardation layer both include a hardened material layer of a second liquid crystal composition containing a polymerizable liquid crystal compound,

The aforementioned first bonding layer is a hardened material layer of an active energy ray curable composition,

The glass transition temperatures of the aforementioned second bonding layer and the aforementioned third bonding layer are both 25°C or lower.

[2] The optical laminate according to [1], wherein the first bonding layer is a cured layer of a radically polymerizable adhesive composition.

[3] The optical laminate according to [1] or [2], wherein the thicknesses of the protective layer, the liquid crystal polarizer, the first liquid crystal retardation layer, and the second liquid crystal retardation layer are all unspecified. up to 20.0μm.

[4] The optical laminate according to any one of [1] to [3], wherein the surface from the surface of the protective layer opposite to the side of the liquid crystal polarizer to the surface of the third bonding layer When the distance between the surface of the second liquid crystal retardation layer and the opposite side is D1 [μm],

The total thickness D2 [μm] of the second bonding layer and the third bonding layer is 40% or more and 70% or less of D1.

[5] The optical laminate according to any one of [1] to [4] further includes an overcoat layer (second layer) that covers the surface of the liquid crystal polarizer on the side of the first bonding layer. protective layer).

According to the present invention, it is possible to provide an optical laminate that includes a liquid crystal polarizer and a liquid crystal retardation layer formed using a polymerizable liquid crystal compound and has excellent moisture and heat resistance.

1: Optical laminated body

10:Polarizing plate

11:Protective layer

15:LCD polarizer

18: Covering layer (second protective layer)

21: 1st liquid crystal phase difference layer

22: 2nd liquid crystal phase difference layer

31: 1st laminating layer

32: 2nd laminating layer

33: The third laminating layer

38:Separation membrane

50:Support part

51:Substrate

52:Frame

53: Rotating table

54:Piston

55:Clamp frame

60: Rotary tool

500:Test piece

501,502: Fixture

B: Grinding the blade

R: rotation axis

W: laminated material

FIG. 1 is a cross-sectional view schematically showing an example of an optical laminate according to an embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating the bending test method of the embodiment.

FIG. 3 is a schematic cross-sectional view schematically showing the end surface processing device used in the embodiment.

Hereinafter, preferred embodiments of the optical laminate will be described with reference to the drawings.

(Optical laminated body)

FIG. 1 is a cross-sectional view schematically showing an example of an optical laminate according to an embodiment of the present invention. As shown in FIG. 1 , the optical laminated body 1 includes a protective layer 11 , a liquid crystal polarizer 15 , a first bonding layer 31 , a first liquid crystal retardation layer 21 , a second bonding layer 32 , and a second liquid crystal retardation layer in this order. layer 22 and the third bonding layer 33. The optical laminated body 1 may further include a coating layer (second protective layer) 18 that covers the surface of the liquid crystal polarizer 15 on the first bonding layer 31 side. In the optical laminate 1, when the coating layer 18 is not included, the protective layer 11 and the liquid crystal polarizer 15 constitute the polarizing plate 10. When the coating layer 18 is included, the protective layer 11, the liquid crystal polarizer 15, and the coating layer 18 constitute the polarizer. Plate 10. The polarizing plate has the function of absorbing the polarized light components parallel to the absorption axis and transmitting the polarized light components orthogonal to the absorption axis. On the side of the third bonding layer 33 included in the optical laminated body 1 opposite to the second liquid crystal retardation layer 22 side, a release film 38 releasable from the third bonding layer 33 may be attached. The optical laminate 1 and the separation film 38 constitute an optical laminate with a separation film.

In the optical laminated body 1, it is preferable that the first bonding layer 31 is in direct contact with the polarizing plate 10 and the first liquid crystal phase difference layer 21, and the second bonding layer 32 is in direct contact with the first liquid crystal phase difference layer 21 and the second liquid crystal phase difference layer 21. The difference layer 22 is in direct contact with the third bonding layer 33 and the second liquid crystal retardation layer 22 in direct contact with each other. The first bonding layer 31 may be directly connected to the liquid crystal polarizer 15 constituting the polarizing plate 10 , or may be directly connected to the covering layer 18 constituting the polarizing plate 10 . In the polarizing plate 10, it is preferable that the protective layer 11 and the liquid crystal polarizer 15 are in direct contact, and the liquid crystal polarizer 15 and the covering layer 18 are in direct contact.

The protective layer 11 can constitute the outermost surface of the viewing side of the optical laminate 1 and can cover and protect the surface of the liquid crystal polarizer 15 . The surface of the protective layer 11 opposite to the side of the liquid crystal polarizer 15 is usually a surface exposed to the atmosphere, and the surface of the protective layer 11 is covered with a peelable surface protection film; or, Used to adhere to the surface covered by a pressure sensitive adhesive layer with a thickness of more than 50 μm on the front panel. Change In other words, the protective layer 11 is composed of layers existing in the range from the surface of the liquid crystal polarizer 15 on the protective layer 11 side to the above-mentioned surface of the protective layer 11 .

The protective layer 11 may have a single-layer structure or a multi-layer structure. The protective layer 11 preferably includes a resin layer. The protective layer 11 may also include, for example, part or all of a first base material layer (described later) coated with a first liquid crystal composition (described later) for forming the liquid crystal polarizer 15 . The details of the protective layer 11 will be described later.

The liquid crystal polarizer 15 includes a hardened material layer of a first liquid crystal composition containing a dichroic dye and a polymerizable liquid crystal compound. Since the liquid crystal polarizer 15 is the hardened material layer of the first liquid crystal composition, compared with a polarizer in which a dichroic pigment is adsorbed and aligned on a polyvinyl alcohol-based resin film, the thickness of the liquid crystal polarizer 15 can be reduced, so it can be used. The optical laminated body 1 is made thinner. The liquid crystal polarizer 15 may have a single-layer structure composed only of the above-mentioned hardened material layer, or may have a multi-layered structure containing, in addition to the above-mentioned hardened material layer, the first liquid crystal composition. The first alignment film is aligned with a polymerizable liquid crystal compound (described later). The details of the liquid crystal polarizer 15 will be described later.

Both the first liquid crystal retardation layer 21 and the second liquid crystal retardation layer 22 include a hardened material layer of a second liquid crystal composition containing a polymerizable liquid crystal compound. Since the first liquid crystal retardation layer 21 and the second liquid crystal retardation layer 22 are the hardened material layers of the second liquid crystal composition, compared with the retardation layer using a resin film, the first liquid crystal retardation layer 21 and the second liquid crystal retardation layer 22 can be reduced. 2 thickness of the liquid crystal retardation layer 22, the optical laminate 1 can be made thin. The first liquid crystal retardation layer 21 and the second liquid crystal retardation layer 22 may have a single-layer structure composed only of the above-mentioned hardened material layer, or may have a multi-layer structure in which, in addition to the above-mentioned hardened material layer, It also contains a second alignment film for aligning the polymerizable liquid crystal compound. The first liquid crystal phase difference layer 21 and the second liquid crystal phase difference layer 22 may include The hardened material layers formed of the same second liquid crystal composition may also include hardened material layers of different second liquid crystal compositions.

The first bonding layer 31 is a hardened material layer of an active energy ray curable composition. In the optical laminated body 1, the liquid crystal polarizer 15 is a cured material layer of the first liquid crystal composition, and the first liquid crystal retardation layer 21 and the second liquid crystal retardation layer 22 are cured material layers of the second liquid crystal composition. Therefore, the thicknesses of the liquid crystal polarizer 15, the first liquid crystal retardation layer 21, and the second liquid crystal retardation layer 22 can be reduced, and the optical laminated body 1 can be made thinner.

Since the first bonding layer 31 is a hardened material layer of the active energy ray curable composition, when the optical laminate 1 is exposed to a hot and humid environment, the transmittance of the transmitted light parallel to the transmission axis direction can be suppressed from decreasing. , it is possible to suppress the recognition of island-like unevenness (shading) in the optical laminate 1 . The reason for this is presumed as follows. Compared with the lamination layer with a glass transition temperature of 25°C or lower (hereinafter also referred to as the "adhesive layer"), the cured material layer of the active energy ray curable composition has a higher cross-linking density. Therefore, when compared with the adhesive layer, the cured layer of the active energy ray curable composition can easily suppress the dichroic dye contained in the liquid crystal polarizer 15 from diffusing to the first liquid crystal retardation layer present in the liquid crystal polarizer 15 The layer on the 21 side can suppress the disorder of the alignment of the dichroic dye in the optical laminate 1. As described above, the optical laminate 1 in which the first bonding layer 31 is a cured layer of an active energy ray curable composition can suppress the above-mentioned decrease in transmittance when exposed to a hot and humid environment. This can suppress the recognition of sea-island unevenness (shading) in the optical laminated body 1 and provide the optical laminated body 1 excellent in moisture and heat resistance.

By using the hardened material layer of the active energy ray curable composition as the first bonding layer 31, compared with using an adhesive layer, the optical laminate 1 is less likely to have scratches when it is subjected to external force. In particular, when the thickness of the protective layer 11 of the optical laminate 1 is small (for example For example, 15 μm or less), in order to prevent scratches from easily occurring on the optical laminate 1, it is preferable that the first bonding layer 31 is a hardened material layer of an active energy ray curable composition.

The active energy ray curable composition used to form the first bonding layer 31 is preferably a radical polymerizable adhesive composition. That is, the first bonding layer 31 is preferably a hardened material layer of a radically polymerizable adhesive composition. The radically polymerizable adhesive composition forms a cross-linked structure through a hardening reaction and the hardness rises quickly, so a hardened material layer with sufficient hardness can be formed immediately after irradiation of active energy rays. In contrast, the cationically polymerizable adhesive composition undergoes a curing reaction slowly, so uncured components remain immediately after active energy ray irradiation. Compared with the cured layer of the radically polymerizable adhesive composition, it is difficult to obtain. A hardened material layer with sufficient hardness tends to be obtained immediately after irradiation of active energy rays. Therefore, compared with the hardened material layer of the cationic polymerizable adhesive composition, the hardened material layer of the radical polymerizable adhesive composition is considered to be less likely to deform when subjected to external force immediately after hardening, and is less likely to be optically laminated. There are traces of foreign body bites remaining on body 1.

The optical laminated body 1 is usually made into a long body, so the layer bonded by the first bonding layer 31 is also a long body. When such a long body is conveyed using a laminating roller and a conveying roller, the contact with these rollers may cause foreign matter bite marks to be produced in the optical layered body 1 obtained. As described above, when the first bonding layer 31 is a cured layer of a radically polymerizable adhesive composition, sufficient hardness can be obtained even immediately after curing, so that it is less likely to deform when receiving force from the outside, and can suppress deformation. The optical laminate 1 has traces of foreign matter being bitten into it.

On the other hand, when the first bonding layer 31 is a hardened material layer of a cationic adhesive composition, it is easy to come into contact with the bonding roller or the conveying roller in a state where the curing reaction does not fully proceed. Therefore, compared with the case where the first bonding layer 31 is a cured layer of a radically polymerizable adhesive composition, shape, it is easy for foreign matter to bite into the optical laminate 1. The details of the first bonding layer 31 will be described later.

It is preferable that the second bonding layer 32 and the third bonding layer 33 have a glass transition temperature (hereinafter also referred to as "Tg") of 25°C or less. A bonding layer with a Tg of 25°C or lower may refer to a so-called adhesive layer formed using an adhesive composition (pressure-sensitive adhesive). The third bonding layer 33 can be a bonding layer for bonding the optical laminated body 1 to the display element of the display device. When the Tg of the third bonding layer 33 is 25° C. or less, the separation film 38 may be bonded on the side of the third bonding layer 33 of the optical laminate 1 opposite to the second liquid crystal retardation layer 22 side.

As shown in FIG. 1 , the distance from the surface of the protective layer 11 on the opposite side to the liquid crystal polarizer 15 side to the surface of the third bonding layer 33 on the opposite side to the second liquid crystal retardation layer 22 side is defined as When D1 [μm], Tg in the first bonding layer 31, the second bonding layer 32, and the third bonding layer 33 is the total thickness Dt [μm] of the layers (adhesive layer) with a temperature of 25°C or lower, The distance D1 is preferably not less than 40% and not more than 70%, more preferably not less than 40% and not more than 67%, it can be not less than 45% and not more than 65%, or it can be not less than 50% and not more than 65%. In the optical laminate 1, among the first bonding layer 31, the second bonding layer 32, and the third bonding layer 33, the layer (adhesive layer) whose Tg is 25° C. or lower is the second bonding layer 32 and The third bonding layer 33. Therefore, the total thickness Dt is equal to the total thickness D2 [μm] of the thickness of the second bonding layer 32 and the thickness of the third bonding layer 33 . At this time, the total thickness D2 is preferably not less than 40% and not more than 70% of the distance D1, more preferably not less than 40% and not more than 67%, and may be not less than 45% and not more than 65%, or may be not less than 50% and not more than 65%. .

The optical laminated body 1 is easily bent due to the above-mentioned thinning, and therefore can be suitably used in a flexible display device in which the display screen can be bent or rolled. When the optical laminated body 1 is applied to a flexible display device and bent, and the total thickness D2 is smaller than the above range, due to the As the third bonding layer 33 expands and contracts, the third bonding layer 33 becomes easily broken. On the other hand, when the total thickness D2 of the second bonding layer 32 and the third bonding layer 33 is greater than the above range, during the polishing process of the optical laminated body 1, the first liquid crystal retardation layer 21 and/or the second liquid crystal The retardation layer 22 becomes prone to cracks. When the optical laminate 1 is subjected to a processing impact, the second bonding layer 32 and the third bonding layer 33 whose Tg is 25° C. or lower tend to be more easily deformed as their total thickness increases. When the second bonding layer 32 and the third bonding layer 33 are greatly deformed, the deformation of the first liquid crystal phase difference layer 21 and/or the second liquid crystal phase difference layer 22 is caused accordingly. Therefore, it is considered that the first liquid crystal phase difference layer 21 is deformed. The difference layer 21 and/or the second liquid crystal phase difference layer 22 become prone to cracks. The details of the second bonding layer 32 and the third bonding layer 33 will be described later.

In the optical laminated body 1 , the thicknesses of the protective layer 11 , the liquid crystal polarizer 15 , the first liquid crystal retardation layer 21 , and the second liquid crystal retardation layer 22 are preferably less than 20.0 μm. The thicknesses of the protective layer 11 , the liquid crystal polarizer 15 , the first liquid crystal retardation layer 21 , and the second liquid crystal retardation layer 22 only need to be less than 20.0 μm, and each independently is preferably 15.0 μm or less, more preferably 10.0 μm or less, more preferably 5.0 μm or less, still more preferably less than 5.0 μm, particularly preferably 4.5 μm or less, most preferably 4.0 μm or less, 3.5 μm or less, or 3.0 μm or less. The thicknesses of the protective layer 11 , the liquid crystal polarizer 15 , the first liquid crystal retardation layer 21 , and the second liquid crystal retardation layer 22 are each independently usually 0.01 μm or more, and may be 0.1 μm or more. When the thickness of each of the above layers is within the above range, it becomes easy to suppress uneven reflection hue at the bent portion when the optical laminate 1 is repeatedly bent.

As long as the thickness of the protective layer 11 is within the above range, it is preferably 0.1 μm or more and less than 20.0 μm, more preferably 0.1 μm or more and 10.0 μm or less, and still more preferably 0.1 μm or more. It is less than 5.0 μm, more preferably not less than 0.1 μm and not more than 4.5 μm, and most preferably not less than 0.1 μm and not more than 4.0 μm.

The thickness of the liquid crystal polarizer 15 only needs to be within the above range, but it is preferably 0.1 μm or more and 10.0 μm or less, more preferably 0.3 μm or more and 5.0 μm or less, and still more preferably 0.5 μm or more and 3.0 μm or less.

The thickness of the first liquid crystal retardation layer 21 and the second liquid crystal retardation layer 22 only needs to be within the above range, but each independently preferably is, for example, 0.1 μm or more and 10.0 μm or less, more preferably 0.3 μm or more and 5.0 μm or less. More preferably, it is 0.3 μm or more and 3.0 μm or less.

The optical laminated body 1 may be a circular polarizing plate. In this case, the optical laminated body 1 may be used as an anti-reflection film.

(Method for manufacturing optical laminate)

The optical laminated body 1 can be laminated with a protective layer 11, a liquid crystal polarizer 15, a first bonding layer 31, a first liquid crystal retardation layer 21, a second bonding layer 32, a second liquid crystal retardation layer 22, and a third bonding layer. Manufactured by combining layers 33. The order in which the layers are stacked is not particularly limited. For example, [i] on the laminate in which the protective layer 11 and the liquid crystal polarizing element 15 are laminated, the first liquid crystal retardation layer 21 and the second liquid crystal retardation layer 22 can be laminated with the second bonding layer 32 interposed therebetween. The laminated body (retardation body) is laminated with the first bonding layer 31 interposed and then the third bonding layer 33 is laminated thereon; [ii] The protective layer 11 and the liquid crystal polarizing element 15 may be laminated on the laminated body, with the third bonding layer 33 interposed therebetween. After the first liquid crystal retardation layer 21 is laminated on the first bonding layer 31, the second liquid crystal retardation layer 22 is laminated via the second bonding layer 32, and the third bonding layer 33 is further laminated.

(display device)

The optical laminate 1 system can be applied to a display device. The display device includes an optical laminated body 1 and a display element. The optical laminated body 1 is arranged on the viewing side of the display element. The optical laminated body 1 can be bonded to a display element using the third bonding layer 33 .

The display device is not particularly limited, and examples thereof include display devices such as organic electroluminescence (organic EL) display devices, inorganic electroluminescence (inorganic EL) display devices, liquid crystal display devices, and electroluminescence display devices. When the optical laminate 1 is a circular polarizing plate, it can be suitably used as an anti-reflection film for an organic EL display device. The optical laminate 1 can be suitably used in a flexible display device in which the display screen can be bent or rolled.

The display device can be used as portable devices such as smartphones and tablets; televisions, digital photo frames, electronic signage, measuring instruments or instruments, office equipment, medical equipment, computer equipment, etc.

Hereinafter, details of each member constituting the optical laminated body and members used for manufacturing each layer will be described.

(Polarizing plate)

The polarizing plate is a film containing a liquid crystal polarizer and exerting the optical function of the liquid crystal polarizer. The polarizing plate may be a liquid crystal polarizer alone, a laminated body directly laminated with a protective layer, or a laminated body in which a protective layer, a liquid crystal polarizer, and a covering layer (second protective layer) are directly laminated.

The polarizing properties of polarizing plates can be measured using a spectrophotometer. For example, a spectrophotometer equipped with a polarizing element can be used to measure the transmittance (T1) in the transmission axis direction (alignment vertical direction) in the range of visible light wavelengths from 380 nm to 780 nm using the double-beam method. And the penetration rate (T2) in the absorption axis direction (alignment direction). The polarization performance in the visible light range is calculated by using the following formulas (Formula 1) and (Formula 2) to calculate the monomer transmittance and polarization degree at each wavelength, and then use JIS The visual sensitivity correction of Z 8701's 2-degree field of view (C light source) can be calculated by the visual sensitivity correction single unit transmittance (Ty) and the visual sensitivity correction polarization (Py). Similarly, from the measured transmittance, the chromaticity a* and b* in the L*a*b* (CIE) color system are calculated using the metachromatic function of the C light source, thereby obtaining the polarizing plate monomer. The hue (single hue), the hue of polarizing plates arranged in parallel (parallel hue), and the hue of polarizing plates arranged orthogonally (orthogonal hue). The closer the a* and b* system values are to 0, the more neutral the hue can be judged to be.

Monomer penetration rate [%]=(T1+T2)/2 (Formula 1)

Polarization degree [%]=〔(T1-T2)/(T1+T2)〕×100 (Formula 2)

The visual sensitivity corrected polarization degree Py of the polarizing plate is usually more than 80%, preferably more than 90%, more preferably more than 95%, still more preferably more than 98%, particularly preferably more than 99%, if it is more than 99.9%, Suitable for use in liquid crystal display devices. Increasing the visual sensitivity of the polarizing plate and correcting the polarization degree Py are beneficial in improving the anti-reflection function of the optical laminate. When the visual sensitivity corrected polarization degree Py is less than 80%, it may be difficult to exert a sufficient anti-reflective function when using the optical laminate as an anti-reflective film.

The greater the visual sensitivity correction monomer transmittance Ty of the polarizer, the greater the clarity of white display. However, from the relationship between (Formula 1) and (Formula 2) above, it can be seen that when the monomer transmittance is too large, There is a problem of reduced polarization. Therefore, the visual sensitivity correction unit transmittance Ty is preferably 30% or more and 60% or less, more preferably 35% or more and 55% or less, still more preferably 40% or more and 50% or less, and still more preferably 40% or more Below 45%. When the sensitivity correction unit transmittance Ty is excessively high, the sensitivity correction polarization degree Py becomes too small, and it may be difficult to exert a sufficient anti-reflection function when the optical laminate is used as an anti-reflection film.

The polarizing plate system [i] can be obtained by directly forming a liquid crystal polarizer on a first base material layer as described later and using the first base material layer as a protective layer; [ii] can have a resin film as the first The base material layer and the surface treatment layer formed on it, and after forming the liquid crystal polarizer on the surface treatment layer, the resin film contained in the first base material layer is removed by peeling off, and the surface treatment layer is used as a protective layer. obtain. Alternatively, [iii] the first base material layer used when forming the liquid crystal polarizer may be peeled off and removed, and a protective layer may be laminated on the liquid crystal polarizer. When the polarizing plate has a coating layer, the coating layer only needs to be formed on the liquid crystal polarizer on the first base material layer.

(Liquid crystal polarizer)

The liquid crystal polarizing element is a film that has an absorption axis and a transmission axis orthogonal to the absorption axis in a plane, absorbs polarized light components parallel to the absorption axis, and transmits polarized light components parallel to the transmission axis. The liquid crystal polarizer is a layer (hardened material layer) composed of a polymer containing a polymerizable liquid crystal compound containing a dichroic dye alone, or a film composed of two layers of this layer and an alignment film. In a liquid crystal polarizer, dichroic pigments are aligned in one direction in the plane. The liquid crystal polarizer can be formed from a first liquid crystal composition containing a polymerizable liquid crystal compound and a dichroic pigment by uniaxially aligning the dichroic pigment and the polymerizable liquid crystal compound. A layer (hardened material layer) composed of a polymer of a polymerizable liquid crystal compound. That is, the liquid crystal polarizer can exhibit a polarizing function by anisotropically absorbing light due to the dichroic pigment contained in the polymer of the polymerizable liquid crystal compound.

The liquid crystal polarization of the hardened material layer including the first liquid crystal composition is characterized by the fact that the hue can be arbitrarily controlled, that the thickness can be greatly reduced, and that there is almost no stretch relaxation due to heat and is non-shrinkable. The system may be suitable for use in flexible display devices, for example.

The liquid crystal polarizer only needs the ratio of the absorbance A1(λ) in the alignment direction of light with wavelength λ [nm] to the absorbance A2(λ) in the vertical direction within the alignment plane (dichroic ratio; A1(λ)/A2(λ) )) is preferably 7 or more, more preferably 20 or more, and still more preferably 40 or more. The larger this value is, the more it can be said to be a liquid crystal polarizer with excellent absorption selectivity. Although it depends on the type of dichroic dye, in the case of a hardened material layer hardened in a nematic liquid crystal phase, the above ratio is about 5 to 10.

By including two or more dichroic dyes with different absorption wavelengths, liquid crystal polarizers can be produced with various hues, and can be made into liquid crystal polarizers with absorption in the entire visible light range. By becoming a liquid crystal polarizer with such absorption characteristics, it can be applied to various applications.

The liquid crystal polarizer can be formed according to the requirements by coating the first liquid crystal composition on the first base material layer on which the first alignment film is formed, and aligning the dichroic pigment contained in the first liquid crystal composition. . In addition to the hardened material layer, the liquid crystal polarizer may also include a first alignment film. The first base material layer can be used directly as a protective layer, or the resin film contained in the first base material layer can be used as a protective layer. Alternatively, the resin film can be peeled off and the resin film contained in the first base material layer can be used as a protective layer. The surface treatment layer is used as a protective layer. The first alignment film can be peeled off and removed together with the resin film. The peeling and removal of the resin film and the first alignment film can be performed after the liquid crystal polarizer and the first liquid crystal retardation layer or the second liquid crystal retardation layer are laminated.

(First liquid crystal composition)

The first liquid crystal composition is a composition for forming a liquid crystal polarizer. In addition to the dichroic dye and the polymerizable liquid crystal compound, it may also contain a solvent, a leveling agent, a polymerization initiator, a sensitizer, a polymerization inhibitor, a crosslinking agent, Joint agents, adhesive agents, and reactive additives, etc.] additives. From the viewpoint of processability, the first liquid crystal composition preferably contains a solvent and a leveling agent.

The polymerizable liquid crystal compound is a compound that has at least one polymerizable group in the molecule and has liquid crystal properties. The polymerizable group means a group that participates in the polymerization reaction, and a photopolymerizable group is preferred. Here, the photopolymerizable group means a group that can participate in the polymerization reaction by active radicals or acids generated from the photopolymerization initiator described below. Examples of polymerizable groups include vinyl, vinyloxy, 1-chlorovinyl, isopropenyl, 4-vinylphenyl, acryloxy, methacryloxy, oxirane, and oxygen. cyclobutanyl etc. Among them, acryloyloxy, methacryloxy, vinyloxy, ethylene oxide and oxetanyl groups are preferred, and methacryloxy and acryloyloxy are more preferred. . The liquid crystal system may be a thermotropic liquid crystal or a liquid crystal. However, when mixed with a dichroic pigment described below, thermotropic liquid crystal is preferred. The polymerizable liquid crystal compound may be a monomer or a polymer that has been polymerized to a dimer or higher.

When the polymerizable liquid crystal compound contained in the first liquid crystal composition is a thermotropic liquid crystal, it may be a thermotropic liquid crystal compound showing a nematic liquid crystal phase or a thermotropic liquid crystal compound showing a smectic liquid crystal phase. . From the viewpoint of obtaining a liquid crystal polarizer (hardened material layer) with a large dichroic ratio, the liquid crystal state displayed by the polymerizable liquid crystal compound is preferably a smectic phase. From the viewpoint of high performance, if High-order smectic phases are better. Among them, smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic I phase, smectic J phase are formed. A higher-order smectic liquid crystal compound of phase, smectic K phase or smectic L phase is more preferred to form a higher-order smectic liquid crystal compound of smectic B phase, smectic F phase or smectic I phase. Liquid crystal compounds are even better. When the liquid crystal phase formed by the polymerizable liquid crystal compound is a higher-order smectic phase, a liquid crystal polarizer (cured material layer) with high polarization performance can be produced. In addition, a liquid crystal polarizer (hardened material layer) with such high polarization performance can obtain black peaks derived from a higher-order structure such as a hexagonal phase or a crystal phase in X-ray diffraction measurement. The black peaks originate from the periodic structure of the molecular alignment. Peaks, layers whose period intervals are from 3 to 6Å can be obtained. From the viewpoint of obtaining higher polarization characteristics, the cured material layer contained in the liquid crystal polarizer is preferably a polymer containing a polymerizable liquid crystal compound that is aligned in a smectic phase state. By.

The polymerizable liquid crystal compound contained in the first liquid crystal composition may be used individually by one type or in combination of two or more types. Relative to the solid content of the first liquid crystal composition, the content of the polymerizable liquid crystal compound in the first liquid crystal composition is preferably not less than 40 mass % and not more than 99.9 mass %, more preferably not less than 60 mass % and not more than 99 mass %, and more preferably Preferably, it is 70 mass % or more and 99 mass % or less. When the content of the polymerizable liquid crystal compound is within the above range, the alignment of the polymerizable liquid crystal compound tends to become high. In addition, in this specification, the solid content means the total amount of components excluding the solvent from the first liquid crystal composition.

色素、花青色素、萘色素、偶氮色素及蒽醌色素等，其中，以偶氮色素為較佳。偶氮色素可列舉：單偶氮色素、雙偶氮色素、參偶氮色素、肆偶氮色素及二苯乙烯(stilbene)偶氮色素等，較佳為雙偶氮色素及參偶氮色素。二色性色素係可單獨，亦可組合，但為了在可見光全區域獲得吸收，以組合2種類以上之二色性色素為較佳，以組合3種類以上之二色性色素為更佳。 The so-called dichroic pigment refers to a pigment that has different absorbance in the long axis direction of the molecule and a different absorbance in the short axis direction. The dichroic pigment preferably has the property of absorbing visible light, and more preferably has an absorption maximum wavelength (λmax) in the range of 380 to 680 nm. Examples of such dichroic pigments include acridine pigments,

Pigments, cyanine pigments, naphthalene pigments, azo pigments, anthraquinone pigments, etc., among which azo pigments are preferred. Examples of azo dyes include monoazo dyes, disazo dyes, ginsenozoic dyes, quaternary azo dyes, and stilbene azo dyes. Preferred are disazo dyes and ginsenozoic dyes. The dichroic dyes may be used alone or in combination. However, in order to obtain absorption in the entire visible light range, a combination of two or more types of dichroic dyes is preferred, and a combination of three or more types of dichroic pigments is more preferred.

Examples of azo dyes include compounds represented by formula (Da).

T ¹ -A ¹ (-N=NA ² ) _p -N=NA ³ -T ² (Da)

[In formula (Da),

A ¹ , A ² , and A ³ independently represent 1,4-phenylene group which may have a substituent, naphthalene-1,4-diyl which may have a substituent, and phenyl benzoate which may have a substituent. group, a 4,4'-stilbenylene group which may have a substituent, or a divalent heterocyclic group which may have a substituent,

T ¹ and T ² represent electron attracting groups or electron releasing groups, and are located substantially at 180° with respect to the azo bonding plane.

p represents an integer from 0 to 4. When p is 2 or more, the respective A ² systems may be the same or different from each other.

In the visible light region, the absorption range is displayed, and the -N=N- bond can be replaced by -C=C-, -COO-, -NHCO-, -N=CH- bond]

From the viewpoint of obtaining good light absorption characteristics, the content of the dichroic dye contained in the first liquid crystal composition (the total amount when plural types are included) is usually 1 to 100 parts by mass of the polymerizable liquid crystal compound. 60 parts by mass or less, preferably 1 to 40 parts by mass or less, more preferably 1 to 20 parts by mass. When the content of the dichroic dye is less than this range, light absorption becomes insufficient and sufficient polarization performance cannot be obtained. When it is more than this range, alignment of liquid crystal molecules may be hindered.

The first liquid crystal composition may contain a solvent. Since the polymerizable liquid crystal compound usually has a high viscosity, it becomes easy to apply by becoming the first liquid crystal composition dissolved in the solvent. As a result, it is often easy to form the hardened material layer of the liquid crystal polarizer. The solvent is preferably one that can completely dissolve the polymerizable liquid crystal compound, and is also preferably a solvent that is inert to the polymerization reaction of the polymerizable liquid crystal compound.

Solvent systems include: alcohol solvents such as methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether and propylene glycol monomethyl ether; ethyl acetate, butyl acetate Ester solvents such as ester, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate and ethyl lactate; acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2 - Ketone solvents such as heptanone and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; aromatic hydrocarbon solvents such as toluene and xylene; nitrile solvents such as acetonitrile; tetrahydrofuran and dimethoxyethane Ether solvents such as alkane; chlorine-containing solvents such as chloroform and chlorobenzene; dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazole Amide solvents such as ketinone and other amide solvents. These solvents can be used alone or in combination of two or more.

The content of the solvent is preferably 50 to 98% by mass relative to the total amount of the first liquid crystal composition. In other words, the solid content in the first liquid crystal composition is preferably 2 to 50 mass%, and more preferably 5 to 30 mass%.

The first liquid crystal composition may also contain a leveling agent. The so-called leveling agent is an additive that adjusts the fluidity of the composition and has the function of making the film obtained by applying the composition flatter. Examples of leveling agents include: organically modified polysiloxane oil-based, polyacrylate-based, and perfluoroalkyl-based leveling agents. Among them, polyacrylate leveling agents and perfluoroalkyl leveling agents are preferred.

When the first liquid crystal composition contains a leveling agent, it is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound.

The first liquid crystal composition may contain a polymerization initiator. The polymerization initiator is a compound that can initiate a polymerization reaction of a polymerizable liquid crystal compound or the like. From the viewpoint of being independent of the phase state of the thermotropic liquid crystal, the polymerization initiator is preferably a photopolymerization initiator that generates active radicals by the action of light.

The photopolymerization initiator only needs to be a compound that can initiate the polymerization reaction of the polymerizable liquid crystal compound, and a known photopolymerization initiator can be used. Specifically, photopolymerization initiators that generate active radicals or acids by the action of light can be cited. Among them, photopolymerization initiators that generate active radicals or acids by the action of light Free radical photopolymerization initiators are preferred. The photopolymerization initiator can be used alone or in combination of two or more.

系化合物、三

系化合物等。產生酸之光聚合起始劑係可使用錪鹽及鋶鹽等。從在低溫之反應效率優異的觀點而言，以自己開裂型之光聚合起始劑為較佳，尤其是，以乙醯苯系化合物、羥基乙醯苯系化合物、α-胺基乙醯苯系化合物、肟酯系化合物為較佳。 The photopolymerization initiator can be a well-known photopolymerization initiator. For example, the photopolymerization initiator that generates active free radicals can use self-cleaving benzoin compounds, acetobenzene compounds, and hydroxyacetyl compounds. Benzene compounds, α-aminoacetobenzene compounds, oxime ester compounds, phosphine oxide compounds, azo compounds, etc., dehydrogenated benzophenone compounds and alkylphenone compounds can be used Compounds, benzoin ether compounds, benzyl ketal compounds, dibenzosuberone compounds, anthraquinone compounds, xanthone compounds, thioxanthone compounds, halogenated acetylbenzene compounds, dialkoxyacetylbenzene compounds, halogenated bisimidazole compounds, trihalogenated compounds

Department of compounds, three

compounds, etc. Examples of photopolymerization initiators that generate acid include iodonium salts, sulfonium salts, and the like. From the viewpoint of excellent reaction efficiency at low temperatures, self-cleavage type photopolymerization initiators are preferred, and in particular, acetobenzene-based compounds, hydroxyacetobenzene-based compounds, and α-aminoacetobenzene-based compounds are preferred. compounds and oxime ester compounds are preferred.

The content of the polymerization initiator in the first liquid crystal composition can be appropriately adjusted according to the type and amount of the polymerizable liquid crystal compound, but is usually 0.1 to 30 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound. , preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass. When the content of the polymerization initiator is within the above range, polymerization can be performed without disturbing the alignment of the polymerizable liquid crystal compound.

The first liquid crystal composition may contain a sensitizer. The sensitizer is preferably a photosensitizer. When the first liquid crystal composition contains a sensitizer, the polymerization reaction of the polymerizable liquid crystal compound contained in the first liquid crystal composition can be further accelerated. The usage amount of the sensitizer is preferably 0.1 to 30 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound.

From the viewpoint of stably advancing the polymerization reaction, the first liquid crystal composition may contain a polymerization inhibitor. The degree of progress of the polymerization reaction of the polymerizable liquid crystal compound can be controlled by the polymerization inhibitor. When the first liquid crystal composition contains a polymerization inhibitor, the content of the polymerization inhibitor is preferably 0.1 to 30 parts by mass relative to 100 parts by mass of the polymerizable liquid crystal compound.

(protective layer)

The protective layer has the function of protecting the surface of the liquid crystal polarizer. The liquid crystal polarizer and the protective layer are directly laminated on each other. Here, the so-called "directly laminated" includes the following aspects: the state in which the protective layer is laminated on the liquid crystal polarizer due to its own adhesion; and the state in which the first alignment film is formed on the protective layer as needed. The first liquid crystal composition for forming the hardened material layer of the liquid crystal polarizer is applied, and the first liquid crystal composition is cured, thereby laminating a protective layer on the liquid crystal polarizer. In order to improve the adhesion with the liquid crystal polarizer, the protective layer may also be subjected to surface activation treatment (for example, corona treatment, etc.), or a thin layer such as an undercoat layer (also called an easy-adhesion layer) may be formed.

The protective layer may be the first base material layer used to form the liquid crystal polarizer, or may include a part of the first base material layer. The protective layer system may have a single-layer structure or a multi-layer structure. The protective layer preferably includes a resin layer. The resin layer can be a resin film and/or a surface treatment layer.

As the resin film, for example, a film excellent in transparency, mechanical strength, thermal stability, moisture barrier properties, isotropy, stretchability, etc. can be used. The resin film may be a thermoplastic resin film. Specific examples of the resin constituting such a resin film include cellulose-based resins such as cellulose triacetate; polyester-based resins such as polyethylene terephthalate and polyethylene naphthalate; polyether resins; Resin; polystyrene-based resin; polycarbonate-based resin; polyamide-based resins such as nylon and aromatic polyamide; polyimide-based resin; chain polyethylene, polypropylene, and ethylene/propylene copolymers, etc. Olefin-based resin; cyclic polyolefin-based resin with a ring system or a norzene structure (also known as norzene-based resin); polymethyl (meth)acrylic resins such as methyl acrylate; polyarylate resins; polystyrene resins; polyvinyl alcohol resins, and mixtures thereof. Resin films of such materials can be easily obtained from the market. The above-mentioned resin may be a (meth)acrylic, urethane, (meth)acrylic urethane, epoxy, polysilicone, or other thermosetting resin or ultraviolet curing resin. . In this specification, "(meth)acrylic acid" means at least one of acrylic acid and methacrylic acid. The same expression is used for (meth)acryl, etc.

Chain polyolefin resins are polyethylene resins (polyethylene resins that are homopolymers of ethylene, or copolymers based on ethylene), polypropylene resins (polypropylene resins that are homopolymers of propylene, or polypropylene resins) In addition to the homopolymers of chain olefins that are the main copolymers), there are also copolymers composed of two or more types of chain olefins.

Cyclic polyolefin resin is a general term for resins polymerized using cyclic olefins as polymerization units. Specific examples of cyclic polyolefin-based resins include ring-opening (co)polymers of cyclic olefins, addition polymers of cyclic olefins, and copolymers of cyclic olefins and chain olefins such as ethylene and propylene ( Representative ones are random copolymers), graft polymers modified with unsaturated carboxylic acids or derivatives thereof, and hydrogenated products thereof. Among them, it is preferable to use a nordesene-based resin using a nordesene-based monomer such as nordesene-based monomer or a polycyclic nordesene-based monomer as a cyclic olefin.

Polyester resins are generally resins with ester bonds in the main chain, and are polycondensates of polycarboxylic acids or their derivatives and polyols. Examples include terephthalic acid, isophthalic acid, dimethyl terephthalate, dimethyl naphthalene dicarboxylate, and the like. Divalent glycols can be used as the polyhydric alcohol, and examples thereof include ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol.

Cellulose ester resin is an ester of cellulose and fatty acid. Specific examples of cellulose ester resins include cellulose triacetate, cellulose diacetate, cellulose tripropionate, and cellulose dipropionate. Copolymers having a plurality of types of polymerized units constituting these cellulose ester resins, or copolymers having a part of the hydroxyl group modified with other substituents, may also be cited. Among these, cellulose triacetate (cellulose triacetate) is particularly preferred.

(Meth)acrylic resin is a resin containing a compound having a (meth)acrylyl group as a main constituent monomer. Specific examples of (meth)acrylic resins include, for example: poly(meth)acrylate such as polymethyl methacrylate; methyl methacrylate-(meth)acrylic acid copolymer; methyl methacrylate- (meth)acrylate copolymer; methyl methacrylate-acrylate-(meth)acrylic acid copolymer; methyl (meth)acrylate-styrene copolymer (MS resin, etc.); with methyl methacrylate Copolymers with alicyclic hydrocarbon-based compounds (for example, methyl methacrylate-cyclohexyl methacrylate copolymer, methyl methacrylate-norzhenyl acrylate copolymer, etc.).

Polycarbonate resin is composed of a polymer in which monomer units are bonded via carbonate groups. The polycarbonate-based resin may be, for example, a resin in which the polymer skeleton is modified, which is called modified polycarbonate, or a copolymerized polycarbonate. Details of the polycarbonate resin are described in Japanese Patent Application Laid-Open No. 2012-31370, for example.

The protective layer can be produced by stretching the above-mentioned resin film (thermoplastic resin film). Examples of the stretching treatment system include uniaxial stretching or biaxial stretching. Examples of the stretching direction include the machine movement direction (MD) of the unstretched film, the direction orthogonal thereto (TD), the direction obliquely intersecting the machine movement direction (MD), and the like.

The protective layer is disposed closer to the recognition side than the liquid crystal polarizer. In order to impart desired surface optical properties or other characteristics, it may also include a resin film and a surface treatment layer provided on the surface of the resin film. Alternatively, the protective layer may not contain a resin film and may include a surface treatment layer as a resin layer. When the protective layer does not contain a resin film and contains a surface treatment layer, for example, the protective layer as the surface treatment layer can be laminated on the liquid crystal polarizer as follows. First, a release treatment is performed to form a release layer on the surface on the side where the surface treatment layer of the resin film is formed by coating a release agent or the like, and preparation is made for forming the surface treatment layer on the release layer. Surface treatment film. Next, the surface treatment film is laminated on the liquid crystal polarizer, the laminate of the liquid crystal polarizer and the first liquid crystal phase difference layer, or the laminate of the liquid crystal polarizer, the first liquid crystal phase difference layer and the second liquid crystal phase difference layer, Peel off the resin film. Thereby, an optical laminated body which does not contain a resin film and contains a surface treatment layer as a protective layer can be obtained.

Examples of surface treatment layers include: hard coating layer, anti-glare layer, anti-reflective layer, anti-static layer, anti-fouling layer, anti-adhesion layer, etc. The surface treatment layer can be formed by coating the surface of the resin film or by forming a release layer on the resin film. When the protective layer includes a resin film, it can also be formed by modifying the surface of the resin film.

The method of forming the surface treatment layer is not particularly limited, and a known method can be used. The surface treatment layer can be formed on one side of the resin film or on both sides.

The hard coating layer has the function of improving the surface hardness of the protective layer and is provided for the purpose of preventing surface scratches. By forming a hard coating layer on the resin film, the hardness and scratch resistance of the protective layer can be improved. The hard coating is preferably a pencil hardness test stipulated in JIS K 5600-5-4: 1999 "General test methods for coatings - Part 5: Mechanical properties of coating films - Section 4: Scratch hardness (Pencil method)" (Place an optical film with a hard coating layer on a glass plate and measure it) It shows a value of H or harder than H.

For the purpose of adjusting the refractive index, increasing the bending elastic coefficient, stabilizing the volume shrinkage, and further improving heat resistance, antistatic properties, anti-glare properties, etc., the hard coat layer may contain various fillers as desired. In addition, the hard coat layer may also contain additives such as antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, leveling agents, and defoaming agents.

(Coating layer)

The polarizing plate may have a coating layer (second protective layer) that covers the surface of the liquid crystal polarizer on the first liquid crystal retardation layer side. The coating layer can be formed by coating the surface of the liquid crystal polarizer with a material (composition) constituting the coating layer, such as a photocurable resin or a water-soluble polymer, and drying or hardening the coating layer. Examples of the photocurable resin include: (meth)acrylic resin, urethane resin, (meth)acrylic urethane resin, epoxy resin, silicone resin, and the like. Examples of water-soluble polymers include poly(meth)acrylamide-based polymers; polyvinyl alcohol, ethylene-vinyl alcohol copolymers, ethylene-vinyl acetate copolymers, (meth)acrylic acid or its anhydride-ethylene Vinyl alcohol polymers such as alcohol copolymers; carboxyvinyl ester polymers; polyvinylpyrrolidone; starch; sodium alginate; polyethylene oxide polymers, etc.

The thickness of the coating layer is usually 0.1 μm or more and 10.0 μm or less, preferably 5.0 μm or less, more preferably 3.0 μm or less. When the thickness of the coating layer is 10 μm or more, the uneven reflection hue of the curved portion becomes easily noticeable in the bending test. When the thickness is less than 0.1 μm, the function of preventing the diffusion of pigments in high temperature environments is easily impaired.

(The first liquid crystal phase difference layer and the second liquid crystal phase difference layer)

The first liquid crystal retardation layer and the second liquid crystal retardation layer are films showing retardation in the plane or in the thickness direction, and are layers (hardened material layers) composed of polymers of polymerizable liquid crystal compounds, or the layers are A film composed of two layers of alignment film. The first liquid crystal retardation layer and the second liquid crystal retardation layer are hardened material layers including a second liquid crystal composition containing a polymerizable liquid crystal compound. The first liquid crystal retardation layer and/or the second liquid crystal retardation layer may each include a second alignment film. The second liquid crystal composition used to form the first liquid crystal retardation layer 21 and the second liquid crystal composition used to form the second liquid crystal retardation layer 22 may be the same as each other or different from each other.

The first liquid crystal retardation layer and the second liquid crystal retardation layer are usually formed by coating the second liquid crystal composition on the second alignment film formed on the second base material layer, and adding the second liquid crystal composition contained in the second liquid crystal retardation layer to the second liquid crystal retardation layer. A polymerizable liquid crystal compound is polymerized and formed. The first liquid crystal retardation layer and the second liquid crystal retardation layer usually include layers in which a polymerizable liquid crystal compound is hardened in an aligned state. In order to generate an in-plane retardation, the polymerizable liquid crystal compound is positioned relative to the second substrate layer. In order to align in the horizontal direction, a hardened material layer in which the polymerizable group of the polymerizable liquid crystal compound is polymerized is required. At this time, when the polymerizable liquid crystal compound is a rod-shaped liquid crystal compound, the liquid crystal retardation layer can be a positive A plate. When the polymerizable liquid crystal compound is a disk-shaped liquid crystal compound, the liquid crystal retardation layer can be a negative A plate.

In order to achieve a high degree of anti-reflection function of the optical laminate, it is necessary that the combination of the first liquid crystal retardation layer and the second liquid crystal retardation layer has a λ/4 plate function (that is, a retardation function of π2) in the entire visible light range. Can. Furthermore, it is preferable that the first liquid crystal retardation layer or the second liquid crystal retardation layer contained in the optical laminate is a reverse wavelength dispersion λ/4 layer. It is also preferable to combine two or more types of liquid crystal retardation layers with different alignments as the first liquid crystal retardation layer and the second liquid crystal retardation layer. Examples of combinations of two or more types of liquid crystal retardation layers include: having a positive wavelength A liquid crystal retardation layer (hereinafter, also referred to as "λ/2 layer") with a dispersive λ/2 plate function (that is, a phase difference function of π) and a λ/4 plate function with positive wavelength dispersion (also referred to as a "λ/2 layer") That is, a combination of a liquid crystal retardation layer (hereinafter also referred to as "λ/4 layer") with a retardation function of π2). Alternatively, from the viewpoint of compensating the anti-reflection function in the oblique direction, one of the first liquid crystal retardation layer and the second liquid crystal retardation layer is a layer having anisotropy in the thickness direction (positive C plate ), the other can be a reverse wavelength dispersion λ/4 layer. In addition, the first liquid crystal retardation layer and the second liquid crystal retardation layer may each form a tilt alignment state or a cholesteric alignment state.

When the combination of the first liquid crystal retardation layer and the second liquid crystal retardation layer is adjusted to have the function of a λ/4 plate in the entire visible light range, the phases of the first liquid crystal retardation layer and the second liquid crystal retardation layer are included. Among the difference bodies, Re (λ) of the in-plane phase difference for light with wavelength λ [nm] preferably satisfies the optical characteristics shown in the following equation (1), and more preferably satisfies the following equations (2) and ( 3) Optical properties shown. A retardation system is a laminated film in which a plurality of retardation plates are laminated, and a laminated film that exhibits a phase difference in the plane or in the thickness direction based on the laminated plurality of retardation plates. The retardation plate is a film including a first liquid crystal retardation layer or a second liquid crystal retardation layer, and exhibits an optical function as the first liquid crystal retardation layer or the second liquid crystal retardation layer.

100nm<Re(550)<160nm (1)

Re(450)/Re(550)≦1.0 (2)

1.00≦Re(650)/Re(550) (3)

[In formulas (1) to (3),

Re(450) represents the in-plane phase difference value of the retardation body for light with a wavelength of 450 nm,

Re(550) represents the in-plane phase difference value of the retardation body for light with a wavelength of 550 nm,

Re(650) represents the in-plane phase difference value of the phase difference body for light with a wavelength of 650nm]

When "Re(450)/Re(550)" in the above formula (2) exceeds 1.0, the light leakage on the short wavelength side of the optical laminated body including the retardation body becomes large. "Re(450)/Re(550)" is preferably 0.7 or more and 1.0 or less, more preferably 0.80 or more and 0.95 or less, still more preferably 0.80 or more and 0.92 or less, particularly preferably 0.82 or more and 0.88 or less. The value of "Re(450)/Re(550)" can be determined by adjusting the mixing ratio of the polymerizable liquid crystal compound in the second liquid crystal composition or the lamination angle of the first liquid crystal retardation layer and the second liquid crystal retardation layer. Or adjust the phase difference value arbitrarily.

The in-plane phase difference values of the first liquid crystal phase difference layer and the second liquid crystal phase difference layer can be adjusted respectively by the thickness of the two liquid crystal phase difference layers. The in-plane retardation value can be determined by the following equation (4). Therefore, in order to obtain the desired in-plane retardation value (Re(λ)), only Δn(λ) and the film thickness d can be adjusted. The thickness of the first liquid crystal retardation layer and the second liquid crystal retardation layer is preferably 0.5 μm or more and 5 μm or less, and more preferably 1 μm or more and 3 μm or less. The thickness of the first liquid crystal retardation layer and the second liquid crystal retardation layer can be measured by an interference type film thickness meter, a laser microscope, or a stylus type film thickness meter respectively. In addition, Δn (λ) depends on the molecular structure of the polymerizable liquid crystal compound described below.

Re(λ)=d×△n(λ) (4)

[In formula (4),

Re(λ) represents the in-plane retardation value of the liquid crystal retardation layer at wavelength λ [nm],

d represents the thickness of the liquid crystal retardation layer,

△n(λ) represents the birefringence at wavelength λ[nm]]

When a combination of a λ/2 layer with positive wavelength dispersion and a λ/4 layer with positive wavelength dispersion is used as a retardation body adjusted to have the function of a λ/4 plate in the entire visible light range, only The layers having optical properties represented by the following formulas (1), formula (6), and formula (7), and the layers having optical properties represented by the following formulas (5) to (7) are specified in a specific manner. Just combine the slow axis relationships.

100nm<Re(550)<160nm (1)

200nm<Re(550)<320nm (5)

Re(450)/Re(550)≧1.00 (6)

1.00≧Re(650)/Re(550) (7)

[In formulas (1) and (5) to (7),

Re(450) represents the in-plane phase difference value of the retardation body for light with a wavelength of 450 nm,

Re(550) represents the in-plane phase difference value of the retardation body for light with a wavelength of 550 nm,

Re(650) represents the in-plane phase difference value of the phase difference body for light with a wavelength of 650nm]

Examples of methods for combining the λ/2 layer and the λ/4 layer include known methods described in Japanese Patent Application Laid-Open No. 2015-163935 or WO2013/137464. From the viewpoint of viewing angle compensation, it is preferable to use a λ/2 layer formed of a second liquid crystal composition containing a disk-shaped polymerizable liquid crystal compound, and a second layer formed of a rod-shaped polymerizable liquid crystal compound. λ/4 layer formed by liquid crystal composition.

The positive C plate is not particularly limited as long as it has anisotropy in the thickness direction. However, when tilt alignment or cholesteric alignment is not performed, the positive C plate has optical characteristics represented by the following formula (8).

nx≒ny<nz (8)

[In formula (8),

nx represents the principal refractive index of the wavelength λ [nm] in the plane of the positive C plate.

ny represents the refractive index of the positive C plate at the wavelength λ [nm] in the same plane as nx and in the direction orthogonal to nx.

nz(λ) represents the refractive index at wavelength λ [nm] in the thickness direction of the positive C plate.

When nx≒ny, nx can be set to the refractive index in any direction within the plane of the positive C plate]

The phase difference value Rth (550) of the positive C plate in the thickness direction at a wavelength of 550nm is usually in the range of -170nm or more and -10nm or less, preferably -150nm or more -20nm or less, and more preferably -100nm or more -40nm. Scope. As long as the phase difference value in the thickness direction is within this range, the anti-reflection properties from the oblique direction can be further improved.

The positive C plate is preferably formed of a second liquid crystal composition containing a rod-shaped polymerizable liquid crystal compound.

In addition to the above-mentioned structures, the first liquid crystal retardation layer and the second liquid crystal retardation layer can be used without particular limitation as long as they have a structure that also achieves an anti-reflection function with respect to tilt alignment or cholesteric alignment. Examples of this structure include well-known structures described in WO2021/060378, WO2021/132616, and WO2021/132624.

(Second liquid crystal composition)

The second liquid crystal composition is a composition for forming the first liquid crystal retardation layer and a composition for forming the second liquid crystal retardation layer. The second liquid crystal composition contains a polymerizable liquid crystal compound and may further contain additives such as a solvent, a leveling agent, a polymerization initiator, a sensitizer, a polymerization inhibitor, a cross-linking agent, an adhesive agent, and a reactive additive. From the viewpoint of processability, the second liquid crystal composition preferably contains a solvent and a leveling agent. Examples of the additives include those described in the first liquid crystal composition, and the content of the additives in the second liquid crystal composition may be within the range described in the first liquid crystal composition.

The polymerizable liquid crystal compound contained in the second liquid crystal composition means a liquid crystal compound having at least one polymerizable group in the molecule, especially a photopolymerizable group. As the polymerizable liquid crystal compound, for example, a polymerizable liquid crystal compound conventionally known in the field of retardation films can be used. The liquid crystal system may be a thermotropic liquid crystal or a liquid crystal, but in terms of controlling the dense film thickness, the thermotropic liquid crystal is preferred. The phase order structure in thermotropic liquid crystals can be nematic liquid crystals or smectic liquid crystals. It can be rod-shaped liquid crystal or disc-shaped liquid crystal. The polymerizable liquid crystal compound can be used alone or in combination of two or more types.

In order to obtain a λ/4 layer with reverse wavelength dispersion, the polymerizable liquid crystal compound used preferably contains birefringence in a direction perpendicular to the long axis direction of the molecule from the viewpoint of expressing reverse wavelength dispersion. T-shaped or H-shaped liquid crystals with a mesogen structure. From the perspective of achieving stronger dispersion, T-shaped liquid crystals are more preferred. Specific examples of T-shaped liquid crystal structures include the following: Compounds represented by formula (I).

[In formula (I),

Ar represents a bivalent aromatic group which may have a substituent. The divalent aromatic group preferably contains at least one of a nitrogen atom, an oxygen atom, and a sulfur atom. When the divalent group Ar contains two or more aromatic groups, the two or more aromatic groups may be bonded to each other through a single bond or a divalent bonding group such as -CO-O-, -O-.

G ¹ and G ² each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group. Here, the hydrogen atom contained in the divalent aromatic group or the divalent alicyclic hydrocarbon group may be a halogen atom, an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, or a fluoroalkyl group having 1 to 4 carbon atoms. The alkoxy group, cyano group or nitro group of 1 to 4 is substituted, and the carbon atoms constituting the divalent aromatic group or the divalent alicyclic hydrocarbon group can be substituted by oxygen atoms, sulfur atoms or nitrogen atoms.

L ¹ , L ² , B ¹ and B ² are independently single bonds or bivalent linking groups.

k and l independently represent integers from 0 to 3, and satisfy the relationship of 1≦k+l. Here, when 2≦k+1, B ¹ and B ² and G ¹ and G ² may be the same as each other or may be different.

E ¹ and E ² each independently represent an alkanediyl group having 1 to 17 carbon atoms. Here, the hydrogen atom contained in the alkanediyl group may be substituted by a halogen atom. The -CH ₂ - contained in the alkanediyl group Systems may be substituted by -O-, -S-, -COO-, and when there are plural -O-, -S-, -COO-, the systems are not adjacent to each other.

P ¹ and P ² independently represent a polymerizable group or a hydrogen atom, and at least one of them is a polymerizable group]

G ¹ and G ² are each independently preferably a 1,4-phenylenediyl group substituted by at least one substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms. , a 1,4-cyclohexanediyl substituted by at least one substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms, more preferably 1,4-cyclohexanediyl substituted by a methyl group, 4-phenylenediyl, unsubstituted 1,4-phenylenediyl, or unsubstituted 1,4-trans-cyclohexanediyl, particularly preferably unsubstituted 1,4-phenylenediyl base diyl, or unsubstituted 1,4-trans-cyclohexanediyl.

Furthermore, it is preferable that at least one of G ¹ and G ² present in plural is a divalent alicyclic hydrocarbon group, and more preferably, at least one of G ¹ and G ² bonded to L ¹ or L ² It is a bivalent alicyclic hydrocarbon group.

L ¹ and L ² are each independently preferably a single bond, an alkylene group having 1 to 4 carbon atoms, -O-, -S-, -R ^a1 OR ^a2 -, -R ^a3 COOR ^a4 -, -R ^a5 OCOR ^a6 -, R ^a7 OC=OOR ^a8 -, -N=N-, -CR ^c =CR ^d -, or C≡C-. Here, R ^a1 to R ^a8 each independently represent a single bond or an alkylene group having 1 to 4 carbon atoms, and R ^c and R ^d represent an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. L ¹ and L ² are each independently more preferably a single bond, -O ^Ra2-1 -, -CH ₂ -, -CH ₂ CH ₂ -, -COOR ^a4-1 -, or OCOR ^a6-1 -. Here, R ^a2-1 , R ^a4-1 , and R ^a6-1 each independently represent any one of a single bond, -CH ₂ -, and -CH ₂ CH ₂ -. L ¹ and L ² are each independently more preferably a single bond, -O-, -CH ₂ CH ₂ -, -COO-, -COOCH ₂ CH ₂ -, or OCO-.

B ¹ and B ² are each independently preferably a single bond, an alkylene group with 1 to 4 carbon atoms, -O-, -S-, -R ^a9 OR ^a10 -, -R ^a11 COOR ^a12 -, -R ^a13 OCOR ^a14 -, or R ^a15 OC=OOR ^a16 -. Here, R ^a9 to R ^a16 each independently represent a single bond or an alkylene group having 1 to 4 carbon atoms. B ¹ and B ² are each independently more preferably a single bond, -OR ^a10-1 -, -CH ₂ -, -CH ₂ CH ₂ -, -COOR ^a12-1 -, or OCOR ^a14-1 -. Here, R ^a10-1 , R ^a12-1 , and R ^a14-1 each independently represent any one of a single bond, -CH ₂ -, and -CH ₂ CH ₂ -. B ¹ and B ² are each independently more preferably a single bond, -O-, -CH ₂ CH ₂ -, -COO-, -COOCH ₂ CH ₂ -, -OCO-, or OCOCH ₂ CH ₂ -.

From the perspective of showing reverse wavelength dispersion, k and l are preferably in the range of 2≦k+l≦6, k+l=4 is better, and k=2 and l=2 are even better. . Since the structure becomes symmetrical when k=2 and l=2, it is preferable.

E ¹ and E ² are each independently preferably an alkanediyl group having 1 to 17 carbon atoms, and more preferably an alkanediyl group having 4 to 12 carbon atoms.

Examples of the polymerizable group represented by P ¹ or P ² include epoxy group, vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloxy group, and methacryl group. Cyloxy group, oxirane group, and oxetanyl group, etc. Among them, acryloyloxy group, methacryloxy group, vinyloxy group, oxirane group and oxetanyl group are preferred, and acryloyloxy group is more preferred.

環、嘧啶環、三唑環、三

環、吡咯啉環、咪唑環、吡唑環、噻唑環、苯并噻唑環、噻吩并噻唑環、噁唑環、苯并噁唑環、及啡啉環等。其中，以具有噻唑環、苯并噻唑環、或苯并呋喃環為較佳，以具有苯并噻唑基為再更佳。又，在Ar含有氮原子時，該氮原子係以具有π電子為較佳。 Ar preferably has at least one selected from the group consisting of an aromatic hydrocarbon ring which may have a substituent, an aromatic heterocyclic ring which may have a substituent, and an electron withdrawing group. Examples of the aromatic hydrocarbon ring include benzene ring, naphthalene ring, anthracene ring, etc., with benzene ring and naphthalene ring being preferred. Examples of the aromatic heterocyclic ring include: furan ring, benzofuran ring, pyrrole ring, indole ring, thiophene ring, benzothiophene ring, pyridine ring, pyridine ring,

ring, pyrimidine ring, triazole ring, tri

ring, pyrroline ring, imidazole ring, pyrazole ring, thiazole ring, benzothiazole ring, thienothiazole ring, oxazole ring, benzoxazole ring, and phenanthroline ring, etc. Among them, those having a thiazole ring, a benzothiazole ring, or a benzofuran ring are preferred, and those having a benzothiazolyl group are even more preferred. Moreover, when Ar contains a nitrogen atom, it is preferable that the nitrogen atom has π electrons.

In formula (I), the total number Nπ of π electrons contained in the divalent aromatic group represented by Ar is preferably 8 or more, more preferably 10 or more, still more preferably 14 or more, and particularly preferably 16 above. Moreover, it is preferably 30 or less, more preferably 26 or less, and still more preferably 24 or less.

Preferable examples of the aromatic group represented by Ar include the following groups.

[In formula (Ar-1) to formula (Ar-23),

＊The symbol system indicates the connecting part,

Z ⁰ , Z ¹ and Z ² each independently represent a hydrogen atom, a halogen atom, an alkyl group with 1 to 12 carbon atoms, a cyano group, a nitro group, an alkyl sulfinyl group with 1 to 12 carbon atoms, and a carbon number of 1 Alkylsulfonyl group to 12, carboxyl group, fluoroalkyl group with 1 to 12 carbon atoms, alkoxy group with 1 to 6 carbon atoms, alkylthio group with 1 to 12 carbon atoms, N- Alkylamino group, N,N-dialkylamino group having 2 to 12 carbon atoms, N-alkylamine sulfonyl group having 1 to 12 carbon atoms or N,N-dialkylamine group having 2 to 12 carbon atoms Sulfonyl group.

Q ¹ and Q ² represent independently -CR ^2' R ^3' -, -S-, -NH-, -NR ^2' -, -CO- or O-, and R ^2' and R ^3' represent independently Ground represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

J ¹ and J ² each independently represent a carbon atom or a nitrogen atom.

Y ¹ , Y ² and Y ³ each independently represent an aromatic hydrocarbon group or an aromatic heterocyclic group which may be substituted.

W ¹ and W ² each independently represent a hydrogen atom, a cyano group, a methyl group or a halogen atom.

m represents an integer from 0 to 6]

Examples of the aromatic hydrocarbon groups in Y ¹ , Y ² and Y ³ include: phenyl, naphthyl, anthracenyl, phenanthrenyl, biphenyl and other aromatic hydrocarbon groups with 6 to 20 carbon atoms, with phenyl and naphthyl being the Preferably, phenyl is more preferred. Examples of aromatic heterocyclic groups include: furyl group, pyrrolyl group, thienyl group, pyridyl group, thiazolyl group, benzothiazolyl group, etc. C4 to 20 carbon atoms containing at least one heteroatom such as nitrogen atom, oxygen atom, sulfur atom, etc. As the aromatic heterocyclic group, furyl, thienyl, pyridyl, thiazolyl and benzothiazolyl are preferred.

Y ¹ , Y ² and Y ³ may each independently be a substituted polycyclic aromatic hydrocarbon group or a polycyclic aromatic heterocyclic group. The polycyclic aromatic hydrocarbon group refers to a condensed polycyclic aromatic hydrocarbon group or a group derived from a collection of aromatic rings. The polycyclic aromatic heterocyclic group refers to a condensed polycyclic aromatic heterocyclic group or a group derived from a collection of aromatic rings.

Z ⁰ , Z ¹ and Z ² are each independently preferably a hydrogen atom, a halogen atom, an alkyl group with 1 to 12 carbon atoms, a cyano group, a nitro group, an alkoxy group with 1 to 12 carbon atoms. Z ⁰ is A hydrogen atom, an alkyl group having 1 to 12 carbon atoms, and a cyano group are more preferably used. Z ¹ and Z ² are a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, and a cyano group.

Q ¹ and Q ² are preferably -NH-, -S-, -NR ^2' -, -O-, and R ^2' is preferably a hydrogen atom. Among them, -S-, -O- and -NH- are particularly preferred.

Among the compounds represented by formulas (Ar-1) to (Ar-23), from the viewpoint of molecular stability, the compounds represented by formulas (Ar-6) and formula (Ar-7) are Better.

環、嘧啶環、吲哚環、喹啉環、異喹啉環、嘌呤環、吡咯烷環等。該芳香族雜環基係可具有取代基。又，Y¹係可為與此進行鍵結之氮原子及Z⁰一起成為前述之可經取代的多環系芳香族烴基或多環系芳香族雜環基。可列舉例如：苯并呋喃環、苯并噻吩環、苯并噁唑環等。 In the compounds represented by formulas (Ar-16) to (Ar-23), Y ¹ can form an aromatic heterocyclic group together with the bonded nitrogen atom and Z ⁰ . Examples of the aromatic heterocyclic group include those mentioned above as aromatic heterocyclic rings that Ar may have. Examples thereof include: pyrrole ring, imidazole ring, pyrroline ring, pyridine ring, pyridine ring, etc.

ring, pyrimidine ring, indole ring, quinoline ring, isoquinoline ring, purine ring, pyrrolidine ring, etc. The aromatic heterocyclic group may have a substituent. In addition, Y ¹ may be a polycyclic aromatic hydrocarbon group or a polycyclic aromatic heterocyclic group which may be substituted together with the nitrogen atom and Z ⁰ bonded thereto. Examples thereof include benzofuran ring, benzothiophene ring, benzoxazole ring, and the like.

Among the polymerizable liquid crystal compounds, compounds having a maximum absorption wavelength of 300 to 400 nm are preferred. It is advantageous in terms of long-term stability of the second liquid crystal composition, and can improve the alignment and film thickness of the hardened material layer of the second liquid crystal composition contained in the first liquid crystal retardation layer and the second liquid crystal retardation layer. the uniformity. In addition, the maximum absorption wavelength of the polymerizable liquid crystal compound can be measured using a UV-visible spectrophotometer in a solvent. The solvent is a solvent capable of dissolving the polymerizable liquid crystal compound, and examples thereof include chloroform.

Examples of the disk-shaped polymerizable liquid crystal compound include compounds containing a group represented by formula (W) (hereinafter, also referred to as "polymerizable liquid crystal compound (W)").

[In the formula (W), R ⁴⁰ represents the following formulas (W-1) to (W-5)]

[In formulas (W-1) to (W-5),

X ⁴⁰ and Z ⁴⁰ each independently represent an alkyldiyl group having 1 to 12 carbon atoms. The hydrogen atom contained in the alkyldiyl group may be substituted by an alkoxy group having 1 to 5 carbon atoms. The alkoxy group is The hydrogen atoms contained can be replaced by halogen atoms. In addition, -CH ₂ - constituting the alkanediyl group may be substituted with -O- or -CO-.

The m2 system represents an integer]

Examples of the rod-shaped polymerizable liquid crystal compound include compounds represented by formula (II), formula (III), formula (IV), formula (V), formula (VI), or formula (VII).

P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-B16-E12-B17-P12 (II)

P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-A14-F11 (III)

P11-B11-E11-B12-A11-B13-A12-B14-A13-B15-E12-B17-P12 (IV)

P11-B11-E11-B12-A11-B13-A12-B14-A13-F11 (V)

P11-B11-E11-B12-A11-B13-A12-B14-E12-B17-P12 (VI)

P11-B11-E11-B12-A11-B13-A12-F11 (VII)

[In formulas (II) to (VII),

A11 to A14 each independently represent a divalent alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group. The hydrogen atom contained in the divalent alicyclic hydrocarbon group and the divalent aromatic hydrocarbon group may be a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group or a nitro group. Substitution, the hydrogen atoms contained in the alkyl group having 1 to 6 carbon atoms and the alkoxy group having 1 to 6 carbon atoms may be substituted by fluorine atoms.

B11 and B17 respectively independently represent -O-, -S-, -CO-O-, -O-CO-, -O-CO-O-, -CO-NR ¹⁶ -, -NR ¹⁶ -CO-, -CO-, -CS-, or single bond. R ¹⁶ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

B12 to B16 represent independently -C≡C-, -CH=CH-, -CH ₂ -CH ₂ -, -O-, -S-, -C(=O)-, -C(=O) -O-, -OC(=O)-, -OC(=O)-O-, -CH=N-, -N=CH-, -N=N-, -C(=O)-NR ¹⁶ - , -NR ¹⁶ -C(=O)-, -OCH ₂ -, -OCF ₂ -, -CH ₂ O-, -CF ₂ O-, -CH=CH-C(=O)-O-, -OC (=O)-CH=CH- or single bond.

E11 and E12 each independently represent an alkyldiyl group having 1 to 12 carbon atoms. The hydrogen atom contained in the alkyldiyl group may be substituted by an alkoxy group having 1 to 5 carbon atoms. The hydrogen atom contained in the alkoxy group The atomic system may be replaced by halogen atoms. In addition, -CH ₂ - constituting the alkanediyl group may be substituted with -O- or -CO-.

F11 represents a hydrogen atom, an alkyl group with 1 to 13 carbon atoms, an alkoxy group with 1 to 13 carbon atoms, a cyano group, a nitro group, a trifluoromethyl group, a dimethylamino group, a hydroxyl group, a hydroxymethyl group, or a formyl group. group, sulfo group (-SO ₃ H), carboxyl group, alkoxycarbonyl group with 1 to 10 carbon atoms or halogen atom, and -CH ₂ - constituting the alkyl group and alkoxy group may be substituted with -O-.

P11 and P12 each independently represent a polymerizable group]

The content of the polymerizable liquid crystal compound in the second liquid crystal composition is, for example, 70 to 99.5 parts by mass, preferably 80 to 99 parts by mass relative to 100 parts by mass of the solid content of the second liquid crystal composition. As long as the content of the polymerizable liquid crystal compound is within the above range, it is advantageous from the viewpoint of the alignment of the obtained cured material layer (liquid crystal cured film). In addition, in this specification, the solid content of the second liquid crystal composition means all the components of the second liquid crystal composition excluding volatile components such as organic solvents.

(1st base material layer, 2nd base material layer)

Examples of the first base material layer coated with the first liquid crystal composition and the second base material layer coated with the second liquid crystal composition include glass base materials and film base materials. The film base material is preferred because it can be continuous. In terms of manufacturing a liquid crystal polarizer or a first liquid crystal retardation layer and a second liquid crystal retardation layer, a long roll-shaped film is better. The first liquid crystal composition and the second liquid crystal composition can be respectively coated on the alignment film formed by the first base material layer and the second base material layer.

Examples of the resin constituting the film base material include: olefin resins such as polyethylene and polypropylene; cyclic olefin resins having a cyclic or norzene structure; polyvinyl alcohol; polyethylene terephthalate, polynaphthalene Polyester resins such as ethylene diformate; poly(meth)acrylic resins; cellulose ester resins such as cellulose triacetate, cellulose diacetate and cellulose acetate propionate; polyester resins Amine resin; polycarbonate; polystyrene; polyether styrene; polyetherketone; polyphenylene sulfide; polyphenylene oxide, etc.

As the film base material, a commercially available cellulose ester resin base material can be used. Examples of such cellulose ester resin base materials include "FUJITAC Film" (manufactured by Fujifilm Co., Ltd.); "KC8UX2M", "KC8UY" and "KC4UY" (above, manufactured by KONICA MINOLTA OPTO Co., Ltd.), etc.

As the cyclic olefin resin constituting the film base material, commercially available cyclic olefin-based resins can also be used. Examples of such cyclic olefin-based resins include "Topas" (registered trademark) (manufactured by Ticona Corporation), "ARTON" (registered trademark) (manufactured by JSR Co., Ltd.), and "ZENOR (ZEONOR)" (registered trademark) ), "ZEONEX (ZEONEX)" (registered trademark) (the above, manufactured by Japan ZEON Co., Ltd.) and "APEL" (registered trademark) (manufactured by Mitsui Chemicals Co., Ltd.).

When using the whole or a part of the first base material layer as a protective layer, the first base material layer preferably has the material and layer structure described for the above protective layer. When using part of the first base material layer as a protective layer, for example, a release layer is formed on the surface of the film base material, and a liquid crystal polarizer is formed on the film base material, and then the film base material can be peeled off and removed.

In terms of quality that is practically operable, the first base material layer and the second base material layer are preferably thin. However, if they are too thin, the strength will decrease and the processability will tend to deteriorate. From this point of view, the thicknesses of the first base material layer and the second base material layer are independently usually 5 μm to 300 μm, preferably 10 μm to 200 μm, and more preferably 10 to 50 μm. The liquid crystal polarizer (hardened material layer of the first liquid crystal composition) is transferred by peeling off the first base material layer, and the first liquid crystal retardation layer and the second liquid crystal retardation layer are transferred by peeling off the second base material layer, Therefore, the optical laminate can be thinned.

(1st alignment film, 2nd alignment film)

The first alignment film and the second alignment film have an alignment regulating force that causes the polymerizable liquid crystal compound to align the liquid crystal in a desired direction.

The first alignment film and the second alignment film facilitate liquid crystal alignment of the polymerizable liquid crystal compound. The states of liquid crystal alignment such as horizontal alignment, vertical alignment, hybrid alignment, and tilt alignment vary depending on the properties of the first alignment film, the second alignment film, and the polymerizable liquid crystal compound, and their combinations can be selected arbitrarily. For example, if the first alignment film and/or the second alignment film is a material that exhibits horizontal alignment as an alignment regulating force, the polymerizable liquid crystal compound can form a horizontal alignment or a mixed alignment. If it is a material that exhibits vertical alignment, the polymerizable liquid crystal compound can Liquid crystal compounds can form vertical alignment or tilt alignment. Expressions such as horizontal and vertical represent the direction of the long axis of the aligned polymerizable liquid crystal compound when the planes of the liquid crystal polarizer, the first liquid crystal retardation layer and the second liquid crystal retardation layer are used as a reference. For example, vertical alignment means having the long axis of the polymerizable liquid crystal compound aligned in a direction perpendicular to the plane of the liquid crystal polarizer, the first liquid crystal retardation layer, or the second liquid crystal retardation layer. The so-called vertical here means 90°±20° with respect to the plane of the liquid crystal polarizer, the first liquid crystal retardation layer or the second liquid crystal retardation layer.

When the alignment film is formed of an alignment polymer, the alignment regulation force can be arbitrarily adjusted according to the surface state or friction conditions. When the alignment film is formed of a photo-alignment polymer, it can be arbitrarily adjusted according to polarized light irradiation conditions. In addition, liquid crystal alignment can also be controlled by selecting physical properties such as surface tension or liquid crystallinity of the polymerizable liquid crystal compound.

When the first alignment film and the second alignment film are formed between the film base material or the glass base material and the hardened material layer of the first liquid crystal composition or the second liquid crystal composition, it is preferable that they are insoluble in the first liquid crystal composition or the second liquid crystal composition. The solvent contained in the second liquid crystal composition is used for solvent removal or alignment polymerization. The liquid crystal compound has heat resistance during heat treatment. The first alignment film and the second alignment film can independently include alignment films composed of alignment polymers, photo alignment films, groove alignment films, stretched films that stretch in the alignment direction, etc., and are suitable for When using a long roll-shaped film, the photo-alignment film is better because the alignment direction can be easily controlled.

The thicknesses of the first alignment film and the second alignment film are independently usually in the range of 10 nm to 5000 nm, preferably in the range of 10 nm to 1000 nm, and more preferably in the range of 30 to 300 nm.

Examples of the alignment polymer used in the friction alignment film include polyamides or gelatins having amide bonds in the molecule, polyimides having amide imine bonds in the molecule, and polyamides of their hydrolysates. Acid, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyglyoxal, polyethyleneimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid and polyacrylate esters, etc. Among them, polyvinyl alcohol is preferred. These alignment polymers can be used alone or in combination of two or more types.

An example of a rubbing method is to apply an oriented polymer composition to a base material and perform annealing to form a film of the oriented polymer on the surface of the film base material or glass base material. A method of bringing the film into contact with a friction roller that rolls up a friction cloth and rotates it.

The photoalignment film is composed of polymers, oligomers or monomers with photoreactive groups. The photoalignment film obtains alignment regulation force by irradiating polarized light. In terms of the point where the direction of the alignment regulating force can be arbitrarily controlled by selecting the polarization direction of the polarized light for irradiation, a photo-alignment film is more preferable.

The so-called photoreactive group refers to a group that generates liquid crystal alignment ability by irradiating light. Specifically, such as alignment induction or anisotropy reaction of molecules produced by irradiation of light, dimers Chemical reaction, photo-crosslinking reaction, or photodecomposition reaction generates photoreactors that become the origin of liquid crystal alignment ability. Among the photoreactive groups, those that cause a dimerization reaction or a photocrosslinking reaction are preferred because of their excellent alignment properties. The photoreactive group that can produce the above reaction is preferably an unsaturated bond, especially one with a double bond, and more preferably one with a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond ( It is at least one group of the group consisting of C=N bond), nitrogen-nitrogen double bond (N=N bond), and carbon-oxygen double bond (C=O bond).

Examples of the photoreactive group having a C=C bond include vinyl, polyalkenyl, distyryl, 4-(2-styrene)pyridyl (stilbazole), and 4-(2-styrene)pyridinium. base, chalcone base and cinnamon base, etc. Chalcone groups and cinnamyl groups are preferred from the viewpoint of easy control of reactivity or alignment control ability during photoalignment. Examples of the photoreactive group having a C=N bond include groups having structures such as aromatic Schiff bases and aromatic hydrazones. Photoreactive groups with N=N bonds include: azophenyl group, azonaphthyl group, aromatic heterocyclic azo group, disazo group, formazan group, etc., or oxyazo group Benzene as the basic structure. Photoreactive groups with C=O bonds include: benzophenone group, coumarin group, anthraquinone group, maleimide group, etc. These groups may also have substituents such as alkyl, alkoxy, aryl, allyloxy, cyano, alkoxycarbonyl, hydroxyl, sulfonate, and halogenated alkyl groups.

In the irradiation of polarized light, the polarized light may be directly irradiated from the film surface, or the polarized light may be irradiated from the side of the film substrate or glass substrate to allow the polarized light to penetrate. In addition, it is particularly preferred that the polarized light is substantially parallel light. The wavelength of the polarized light for irradiation is a wavelength region in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb light energy. Specifically, UV (ultraviolet light) having a wavelength in the range of 250 to 400 nm is particularly preferred.

(1st laminating layer, adhesive layer)

The first bonding layer is a hardened material layer of the active energy ray curable composition and is called a so-called adhesive layer. The adhesive layer can be formed using an adhesive composition.

Examples of the adhesive composition include aqueous adhesive compositions and active energy ray curable compositions cured by heating or irradiation with active energy rays such as ultraviolet rays, visible light, electron beams, and X-rays. Examples of the water-based adhesive composition include those in which polyvinyl alcohol-based resin or urethane resin as the main component is dissolved in water, and polyvinyl alcohol-based resin or urethane resin as the main component is dispersed in Made of water. The water-based adhesive composition may further include hardening components or cross-linking agents such as polyhydric aldehydes, melamine compounds, zirconium oxide compounds, zinc compounds, glyoxal compounds, and water-soluble epoxy resins.

The adhesive composition is preferably an active energy ray curable composition containing a curable (polymerizable) compound as a main component and cured by irradiation of active energy rays. Examples of active energy ray curable compositions include: a cationically polymerizable adhesive composition containing a cationically polymerizable compound as a curable compound; a radically polymerizable adhesive composition containing a radically polymerizable compound as a curable compound; Mixed adhesive compositions using both a cationically polymerizable compound and a radically polymerizable compound as a curable compound.

The cationic polymerizable compound is a compound or oligomer that undergoes a cationic polymerization reaction and hardens by irradiation or heating with active energy rays such as ultraviolet light, visible light, electron rays, X-rays, etc. Specific examples include epoxy compounds and oxygen heterocycles. Butane compounds, vinyl compounds, etc.

Examples of the epoxy compound include alicyclic epoxy compounds such as 3,4-epoxycyclohexanecarboxylic acid 3,4-epoxycyclohexylmethyl ester (having one or more alicyclic ring bonds in the molecule) Compounds with bonded epoxy groups); aromatic epoxy compounds such as bisphenol A's diepoxypropyl ether (compounds with aromatic rings and epoxy groups in the molecule); 2-ethylhexylepoxypropyl Ether, 1,4-butanediol diglycidyl ether Aliphatic epoxy compounds (compounds with at least one ethylene oxide ring bonded to an aliphatic carbon atom in the molecule), etc.

Examples of the oxetane compound include 3-ethyl-3-{[(3-ethyloxetan-3-yl)methoxy]methyl}oxetane and the like. Compounds with more than one oxetane ring.

The cationically polymerizable adhesive composition preferably contains a cationic polymerization initiator. The cationic polymerization initiator may be a thermal cationic polymerization initiator or a photocationic polymerization initiator. Examples of the cationic polymerization initiator include aromatic diazonium salts such as hexafluoroantimonate diazobenzene salt; aromatic iodonium salts such as diphenylsulfonium 4 (pentafluorophenyl) borate; triphenylsulfonium hexanate. Aromatic sulfonium salts such as fluorophosphates; iron-aromatic hydrocarbon complexes such as xylene-cyclopentadienyl iron(II) hexafluoroantimonate ester, etc. The content of the cationic polymerization initiator is usually 0.1 to 10 parts by mass relative to 100 parts by mass of the cationically polymerizable compound. The cationic polymerization initiator system may contain two or more types.

Examples of the cationically polymerizable adhesive composition include the cationically polymerizable compositions described in Japanese Patent Application Laid-Open No. 2016-126345 and Japanese Patent Application Laid-Open No. 2021-113969.

The radically polymerizable compound is a compound or oligomer that undergoes a radical polymerization reaction and hardens by irradiation or heating with active energy rays such as ultraviolet light, visible light, electron rays, X-rays, etc. Specific examples include those having an ethylenically unsaturated bond. compound. Examples of the compound having an ethylenically unsaturated bond include (meth)acrylic compounds having one or more (meth)acrylyl groups in the molecule, vinyl compounds having one or more vinyl groups in the molecule, and the like.

Examples of the (meth)acrylic compound include (meth)acrylate monomers having at least one (meth)acryloxy group in the molecule, (meth)acrylamide monomers, and combinations of two or more types thereof. (Meth)acrylyl group-containing compounds such as (meth)acrylic acid oligomers having at least two (meth)acrylyl groups in the molecule obtained by reacting functional group-containing compounds.

The radical polymerizable adhesive composition preferably contains a radical polymerization initiator. The radical polymerization initiator may be a thermal radical polymerization initiator or a photo-radical polymerization initiator. Examples of free radical polymerization initiators include acetobenzene-based initiators such as acetobenzene and 3-methylacetobenzene; benzophenone, 4-chlorobenzophenone, and 4,4'-diamino Benzophenone-based initiators such as benzophenone; benzoin ether-based initiators such as benzoin propyl ether and benzoin ethyl ether; thioxanthrene such as 4-isopropylthiaxanthone Ketone starters; xanthone, quinone, etc. The content of the radical polymerization initiator is usually 0.1 to 10 parts by mass relative to 100 parts by mass of the radically polymerizable compound. The radical polymerization initiator may contain two or more types.

Examples of the radically polymerizable adhesive composition include the radically polymerizable compositions described in Japanese Patent Application Publication No. 2016-126345, Japanese Patent Application Publication No. 2016-153474, and International Publication No. 2017/183335.

The composition of the active energy ray curable adhesive can contain ion trapping agents, antioxidants, chain moving agents, tackifiers, thermoplastic resins, fillers, flow regulators, plasticizers, defoaming agents, anti-oxidants, etc. Additives such as electrostatic agents, leveling agents, solvents, etc.

The adhesive composition can be coated on the bonding surface of at least one of the two layers bonded by the first bonding layer or the adhesive layer, and the two layers can be separated through the coating layer of the adhesive composition. After overlapping and laminating by pressing from above and below using a laminating roller or the like, the coating layer is dried, and the coating layer is irradiated with active energy rays and hardened, or heated and hardened.

Before forming the coating layer of the adhesive composition, at least one of the bonding surfaces of the above two layers may be subjected to saponification treatment, corona treatment, plasma treatment, primer treatment, anchor coating treatment, etc. Then process.

In forming the coating layer of the adhesive composition, various coating methods such as die slot coater, notch wheel coater, gravure coater, wire bar coater, and blade coater can be used.

The light irradiation intensity when irradiating active energy rays is not particularly limited as long as it is determined according to each composition of the active energy ray curable adhesive composition, but it is preferably 10 mW/cm ² or more and 1,000 mW/cm ² or less. . In addition, the irradiation intensity is preferably the intensity in the wavelength region effective for activation of the photocationic polymerization initiator or the photoradical polymerization initiator. When irradiating with such light irradiation intensity once or multiple times, the cumulative light amount is preferably 10 mJ/cm ² or more, more preferably 100 mJ/cm 2 or ^more and 1,000 mJ/cm ² or less.

The light source used for polymerization and hardening of the active energy ray curable adhesive composition is not particularly limited, but examples thereof include: low-pressure mercury lamp, medium-pressure mercury lamp, high-pressure mercury lamp, ultra-high-pressure mercury lamp, xenon lamp, halogen lamp, chemical lamp, Black light lamp, microwave excited mercury lamp, metal halide lamp.

The thickness of the adhesive layer formed from the water-based adhesive composition may be, for example, 5 μm or less, preferably 1 μm or less, more preferably 0.5 μm or less, and may be 0.01 μm or more, preferably 0.05 μm or more.

The thickness of the hardened material layer (adhesive layer) formed of the active energy ray curable adhesive composition may be, for example, 10 μm or less, preferably 5 μm or less, more preferably 3 μm or less, and may be 0.1 μm or more. It is preferably 0.5 μm or more, and more preferably 1 μm or more.

(2nd laminating layer, 3rd laminating layer)

The second bonding layer and the third bonding layer are bonding layers whose glass transition temperature Tg is 25°C or lower. The bonding layer with a Tg of 25° C. or lower can be formed using an adhesive composition, for example. The Tg of the lamination layer can be measured by a differential scanning calorimeter (DSC).

The adhesive composition is not particularly limited, and conventionally known adhesive compositions with excellent optical transparency can be used. For example, (meth)acrylic resins, urethane resins, polysiloxane resins, Adhesive composition of base polymer such as polyvinyl ether resin. Moreover, it may be an active energy ray hardening type adhesive composition, a thermosetting type adhesive composition, etc. Among these, an adhesive composition using an acrylic resin as a base polymer which is excellent in transparency, adhesion, re-peelability, weather resistance, heat resistance, etc. is suitable.

The adhesive composition system may further include cross-linking agents, silane compounds, antistatic agents, etc.

The (meth)acrylic resin contained in the adhesive composition is a structural unit derived from an alkyl (meth)acrylate represented by the following formula (VIII) (hereinafter, also referred to as "structural unit (VIII)") ) is a polymer (hereinafter also referred to as "(meth)acrylate polymer") as a main component (for example, containing 50 parts by mass or more with respect to 100 parts by mass of the structural unit of the (meth)acrylic resin). Better.

[In formula (VIII),

R ¹⁰ represents a hydrogen atom or a methyl group,

R ²⁰ represents an alkyl group having 1 to 20 carbon atoms. The alkyl group can have any structure of linear, branched or cyclic. The hydrogen atom of the alkyl group can be an alkoxy group having 1 to 10 carbon atoms. base substitution]

Examples of the (meth)acrylate represented by formula (VIII) include: (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (meth)acrylic acid n-propyl ester, (meth)acrylic acid ethyl ester Isopropyl acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-pentyl (meth)acrylate ester, n-hexyl (meth)acrylate, isohexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate , 2-ethylhexyl (meth)acrylate, n- and isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, (meth)acrylic acid n-dodecyl ester, cyclohexyl (meth)acrylate, isozyl (meth)acrylate, stearyl (meth)acrylate, tert-butyl (meth)acrylate, etc. Specific examples of the alkoxy-group-containing alkyl acrylate include 2-methoxyethyl (meth)acrylate, epoxymethyl (meth)acrylate, and the like. Among them, those containing n-butyl (meth)acrylate or 2-ethylhexyl (meth)acrylate are preferred, and those containing n-butyl (meth)acrylate are particularly preferred.

The (meth)acrylate polymer system may contain structural units derived from monomers other than structural unit (VIII). The number of structural units derived from other monomers may be one type or two or more types. Examples of other monomers that the (meth)acrylate polymer may include include monomers having polar functional groups, monomers having aromatic groups, and acrylamide-based monomers.

Examples of the monosystem having a polar functional group include (meth)acrylate having a polar functional group. Examples of polar functional groups include: hydroxyl group; carboxyl group; substituted amino group or unsubstituted amino group substituted with an alkyl group having 1 to 6 carbon atoms; heterocyclic groups such as epoxy group, etc.

The content of structural units derived from monomers having polar functional groups in the (meth)acrylate polymer is preferably 10 parts by mass or less relative to 100 parts by mass of all structural units of the (meth)acrylate polymer. More preferably, it is not less than 0.5 parts by mass and not more than 10 parts by mass, and still more preferably not less than 1 part by mass and not more than 5 parts by mass.

A single system with an aromatic group can have one (meth)acrylyl group and one or more aromatic rings (for example, benzene ring, naphthalene ring, etc.) in the molecule, and examples include phenyl group and phenoxyethyl group. , or benzyl (meth)acrylate.

The content of the structural units derived from the monomer having an aromatic group in the (meth)acrylate polymer is preferably 4 parts by mass or more 20 Parts by mass or less, more preferably 4 parts by mass or more and 15 parts by mass or less.

Examples of acrylamide-based monosystems include: N-(methoxymethyl)acrylamide, N-(ethoxymethyl)acrylamide, N-(propoxymethyl)acrylamide, N -(Butoxymethyl)acrylamide, N-(2-methylpropoxymethyl)acrylamide, etc.

Furthermore, structural units derived from monomers other than structural unit (VIII) may include structural units derived from styrene-based monomers, structural units derived from vinyl-based monomers, and structural units derived from monomers having plural numbers in the molecule. The structural unit of a (meth)acrylyl monomer, etc.

The weight average molecular weight (hereinafter, also referred to simply as "Mw") of the (meth)acrylic resin is preferably 500,000 to 2.5 million. When the weight average molecular weight is more than 500,000, the durability of the adhesive layer in high temperature and high humidity environments can be improved. When the weight average molecular weight is 2.5 million or less, the workability when applying the coating liquid containing the adhesive composition becomes good. The molecular weight distribution (Mw/Mn) expressed as the ratio of the weight average molecular weight (Mw) and the number average molecular weight (hereinafter, also referred to as "Mn") is usually 2 to 10. The so-called "weight average molecular weight" and "number average molecular weight" in this specification are polystyrene-converted values measured by gel permeation chromatography (GPC).

When (meth)acrylic resin is dissolved in ethyl acetate and becomes a solution with a concentration of 20% by mass, the viscosity at 25°C is preferably 20 Pa‧s or less, and more preferably 0.1 to 15Pa‧s. good. When the viscosity of the (meth)acrylic resin at 25°C is within the above range, the durability of the optical laminate including the adhesive layer formed of the above resin is improved, and it is helpful for reworkability. The above viscosity system can be measured by a Brookfield viscometer.

The glass transition temperature (Tg) of the (meth)acrylic resin is, for example, -60 to 20°C, preferably -50 to 15°C, more preferably -45 to 10°C, still more preferably -40 to 0°C . In addition, the glass transition temperature can be measured with a differential scanning calorimeter (DSC).

The (meth)acrylic resin system may contain two or more kinds of (meth)acrylate polymers. Examples of such (meth)acrylate polymers include those containing the structural unit (VIII) derived from the aforementioned (meth)acrylate as a main component, and having a weight average molecular weight in the range of, for example, 50,000 to 300,000. A relatively low molecular weight (meth)acrylate polymer.

(Meth)acrylic resins can generally be produced by known polymerization methods such as solution polymerization, block polymerization, suspension polymerization, and emulsion polymerization. In the production of (meth)acrylic resin, polymerization is usually performed in the presence of a polymerization initiator. The usage amount of the polymerization initiator is usually 0.001 to 5 parts by mass relative to a total of 100 parts by mass of all monomers constituting the (meth)acrylic resin.

The adhesive composition preferably contains a cross-linking agent. The cross-linking agent can include commonly used cross-linking agents (for example, isocyanate compounds, epoxy compounds, aziridine compounds, metal chelate compounds, peroxides, etc.). In particular, from the operating time of the adhesive composition, From the viewpoints of cross-linking speed, durability of the polarizing plate, etc., isocyanate-based compounds are preferred. For example, the proportion of the crosslinking agent is 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass relative to 100 parts by mass of the (meth)acrylic resin.

The adhesive composition may further contain a silane compound. The content of the silane compound in the adhesive composition is usually 0.01 to 10 parts by mass relative to 100 parts by mass of the (meth)acrylic resin.

The adhesive composition may further include an antistatic agent. Examples of the antistatic agent include known ones, and ionic antistatic agents are suitable. In view of the excellent stability of the antistatic properties over time of the adhesive composition, an ionic antistatic agent that is solid at room temperature is preferred. The content of the antistatic agent is preferably 0.01 to 20 parts by mass, more preferably 1 to 7 parts by mass relative to 100 parts by mass of the (meth)acrylic resin.

The thickness of the adhesive layer is usually 0.1 to 30 μm, preferably 3 to 30 μm, and more preferably 5 to 25 μm.

The storage elastic coefficient of the adhesive layer at a temperature of 25°C is preferably 1.0×10 ⁴ Pa to 1.0×10 ⁶ Pa, more preferably 1.0×10 ⁴ Pa to 1.0×10 ⁵ Pa. The storage elastic coefficient can be obtained by dynamic viscoelasticity measurement.

The latent variable ΔCr of the adhesive layer at a temperature of 70°C is, for example, 65 μm or less, and may be 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less, 30 μm or less, 25 μm or less, 20 μm or less, and further may be 15 μm or less. The lower limit of the latent variable ΔCr is, for example, 0.5 μm. If the latent variable is in such a range, similar to the case of storing the elastic coefficient, it is possible to suppress glue shortage, glue contamination, and cutting failure when cutting the optical laminated body. In addition, the creep value can be measured, for example, according to the following procedure: Apply a load of 500 gf vertically downward to an adhesive layer attached to a stainless steel test plate with a joint surface of 20 mm in length x 20 mm in width. The test plate is fixed. At each time point 100 seconds and 3600 seconds after the load is applied, the latent variable (offset) of the adhesive layer relative to the test plate is measured and set to Cr ₁₀₀ and Cr ₃₆₀₀ respectively. From the measured Cr ₁₀₀ and Cr ₃₆₀₀ , the latent variable ΔCr can be obtained by the formula ΔCr=Cr ₃₆₀₀ -Cr ₁₀₀ .

(separation membrane)

The release film is peelable from the third bonding layer for bonding the optical laminate to the display element, and covers and protects the surface of the third bonding layer. When the release film is peeled off from the third bonding layer of the optical laminate with a release film, the release film can be peeled off while maintaining the shape of the third bonding layer. The separation membrane is preferably one that has a base film and a release treatment layer. Examples of the base film include a film formed of a resin. Examples of the resin include film base materials used for the first base material layer and the second base material layer. The release treatment layer only needs to be a known release treatment layer, and examples thereof include a layer formed by coating a base film with a release agent such as a fluorine compound or a polysiloxy compound.

[Example]

Hereinafter, the present invention will be explained more specifically by showing examples, but the present invention is not limited to these examples. "%" and "parts" in the examples and comparative examples mean "mass %" and "mass parts" unless otherwise specified.

[Measurement of thickness]

Unless otherwise specified, the thickness of each layer is measured using a laser microscope (LEXT, manufactured by OLYMPUS Co., Ltd.) or a digital micrometer (DIGITAL MICROMETER) manufactured by NIKON Co., Ltd. "MH" -15M".

[Production of polarizing plate (1) with base material layer]

(Preparation of the first liquid crystal composition)

The following components were mixed and stirred at a temperature of 80° C. for 1 hour to obtain a first liquid crystal composition. The polymerizable liquid crystal compounds (X1) and (X2) have structures shown below. Dichroic pigment (DP1) (DP3) is an azo dye described in the Example of Japanese Patent Application Laid-Open No. 2013-101328, and has the structure shown below.

Polymerizable liquid crystal compound (X1): 75 parts

Polymerizable liquid crystal compound (X2): 25 parts

Dichroic pigment (DP1): 2.5 parts

Dichroic pigment (DP2): 2.5 parts

Dichroic pigment (DP3): 2.5 parts

Polymerization initiator [2-dimethylamino-2-phenylmethyl-1-(4-morpholinylphenyl)butan-1-one (IRGACURE (registered trademark) 369; manufactured by BASF JAPAN] : 6 servings

Leveling agent [polyacrylate compound (BYK-361N; BYK-Chemie Co., Ltd.)]: 1.2 parts

Solvent [o-xylene]: 250 parts

‧Polymerizable liquid crystal compound (X1):

‧Polymerizable liquid crystal compound (X2):

‧Dichroic pigment (DP1):

‧Dichroic pigment (DP2):

‧Dichroic pigment (DP3):

(Preparation of composition (1) for forming photo-alignment film)

The following components described in Japanese Patent Application Laid-Open No. 2013-033249 were mixed, and the resulting mixture was stirred at 80° C. for 1 hour to obtain a photo alignment film forming composition (1).

‧Photo-alignment polymer with the following structure: 2 parts

‧Solvent [o-xylene]: 98 parts

(Preparation of water-soluble polymer aqueous solution)

According to the following synthesis scheme, a water-soluble polymer composed of the following structural units is obtained.

20 g of polyvinyl alcohol (manufactured by Wako Pure Chemical Industries, Ltd.) with a molecular weight of 1,000, 0.55 mg of N,N-dimethyl-4-aminopyridine as a nucleophile, and triethyl were added to 400 g of dimethylsulfoxide. 4.6 g of base amine was dissolved, and the temperature was raised to 60°C while stirring. Thereafter, a solution in which 10.5 g of methacrylic anhydride was dissolved in 50 g of dimethylsulfoxide was added dropwise over 1 hour. The mixture was heated and stirred at 60° C. for 14 hours to react. After cooling the obtained reaction solution to room temperature, 481 g of methanol was added to the reaction solution and stirred to mix completely, thereby adjusting so that the ratio (mass) of the reaction solution to methanol became 1:1. By slowly adding 1500 mL of acetone to this solution, the water-soluble polymer was crystallized by crystallization. The solution containing the obtained white crystals was filtered, washed thoroughly with acetone, and then vacuum-dried to obtain 20.2 g of a water-soluble polymer. The obtained water-soluble polymer was dissolved in water to prepare a 3 mass% water-soluble polymer aqueous solution.

(Preparation of composition for forming HC layer)

The following components were mixed and stirred at a temperature of 50° C. for 4 hours to obtain a composition for forming a hard coat (HC) layer.

‧Acrylate monomer with the following structure: 70 parts

‧Urethane acrylate resin [EBECRYL4858 (manufactured by DAICEL-ALLNEX Co., Ltd.)]: 30 parts

‧Polymerization initiator [Omnirad907 (manufactured by IGM Resins B.V)]: 3 parts

‧Solvent [methyl ethyl ketone]: 10 parts

(Production of polarizing plate (1) with base material layer)

Roll-shaped release polyethylene terephthalate (PET) film with a film width of 800 mm ("FF-50" manufactured by UNITIKA Co., Ltd., single-sided release-treated PET film (thickness of support substrate: 50 μm)) On the release treatment surface, the HC layer-forming composition obtained above was continuously coated with a slit die coater, and dried at a temperature of 100°C for 2 minutes to form an HC layer (protective layer) with a thickness of 2.00 μm. . Thereby, a film in which an HC layer is laminated on the release-treated surface of a single-sided release-treated PET film can be obtained as the first base material layer (1).

After plasma treatment is applied to the HC layer of the first base material layer (1), the above-prepared photo alignment film forming composition (1) is coated using a slit die coater, and is separated on one side. The coating layer is formed in the 600mm width range of the central part of the mold-processed PET film. Next, the solvent was removed by conveying in a ventilated drying oven set at a temperature of 100° C. for 2 minutes, and the coating layer on the HC layer was dried. Thereafter, the dried coating layer was irradiated with polarized UV light in a direction 90° relative to the length direction of the single-sided release-treated PET film at an intensity of 20 mJ/cm ² (based on 313 nm). This imparts alignment regulation force, and a photo-alignment film (1) is formed on the HC layer. The thickness of the photo-alignment film (1) is about 50nm.

On the photo alignment film (1) formed on the first base material layer (1), the first liquid crystal composition prepared above is coated using a slit die coater, and on the first base material layer (1) 1) The coating layer is formed within the width of 600mm in the central part. Next, the solvent was removed by conveying in a ventilated drying oven set at a temperature of 110° C. for 2 minutes, and the coating layer on the first base material layer (1) was dried. Thereafter, a high-pressure mercury lamp is used to irradiate ultraviolet light at 1000 mJ/cm ² (based on 365 nm) to harden the polymerizable liquid crystal compound contained in the dried coating layer, thereby forming a hardened material layer of the first liquid crystal composition. A liquid crystal polarizing element (1) with a base material layer in which a photo alignment film (1) and a hardened material layer (combined into a liquid crystal polarizing element) are sequentially formed on the first base material layer (1) is obtained. The liquid crystal polarizer (1) with a base material layer has an absorption axis in a direction of 90° with respect to the longitudinal direction. The thickness of the hardened material layer is 3 μm.

Then, after plasma treatment is applied to the liquid crystal polarizer side of the liquid crystal polarizer (1) with the base material layer, the water-soluble polymer aqueous solution prepared above is continuously coated using a slit die coater. , and dried at a temperature of 100° C. for 2 minutes to form a coating layer (second protective layer) with a thickness of 2 μm. In this way, a strip-shaped strip including the first base material layer (1) (single-sided release-treated PET film/HC layer)/liquid crystal polarizer (photo alignment film (1)/hardened material layer)/coating layer is obtained in this order. Polarizing plate with base material layer (1).

The obtained polarizing plate (1) with a base material layer was cut into a square of 40 mm×40 mm. After bonding the coating layer side to an alkali-free glass plate (manufactured by CORNING Co., Ltd., trade name "Eagle-XG") using an acrylic adhesive (manufactured by Lintec Co., Ltd., trade name "P-3132") with a thickness of 25 μm, The single-sided release-treated PET film was peeled off to obtain a test body.

Using a spectrophotometer (UV-3150 manufactured by Shimadzu Corporation) equipped with a folding clip with a polarizing element, the obtained test specimen was measured in the wavelength range of 380 to 680 nm in 2 nm steps by the double-beam method. The monomer penetration rate in the penetration axis direction (T1) and the monomer penetration rate in the absorption axis direction (T2). Using the following formulas (Formula 1) and (Formula 2), calculate the single transmittance and polarization degree at each wavelength, and then correct the visual sensitivity by using the 2-degree field of view (C light source) of JIS Z 8701 to calculate the visual sensitivity. Corrected monomer transmittance (Ty) and visual sensitivity corrected polarization (Py).

Monomer penetration rate [%]=(T1+T2)/2 (Formula 1)

Polarization degree [%]=〔(T1-T2)/(T1+T2)〕×100 (Formula 2)

As a result, the visual sensitivity-corrected single-unit transmittance (Ty) of the test object was 42%, and the visual sensitivity-corrected polarization degree (Py) was 97%, confirming that these values are useful as a polarizing plate. Furthermore, at a temperature of 100 After heating the test body for 120 hours at ℃, when calculating the visual sensitivity corrected monomer transmittance (Ty) and visual sensitivity corrected polarization (Py) according to the above procedure, the visual sensitivity corrected monomer transmittance of the test system after heating ( Ty) is also 42%, the visual sensitivity corrected polarization (Py) is also 97%, and no reduction in optical performance is observed.

[Production of polarizing plate (2) with base material layer]

The polarizing plate with base material layer was produced by following the production procedure of polarizing plate with base material layer (1) except that the thickness of the HC layer (protective layer) formed on the single-sided release-treated PET film was changed to 3.95 μm. (2).

[Production of polarizing plate (3) with base material layer]

Except that the thickness of the HC layer (protective layer) formed on the single-sided release-treated PET film was changed to 4.95 μm, the polarizing plate with base material layer (1) was produced using the same production process as the polarizing plate with base material layer (1). 3).

[Preparation of the first liquid crystal retardation layer (1)]

(Preparation of alignment film forming composition (1))

Water was added to commercially available polyvinyl alcohol (polyvinyl alcohol 1000 fully saponified type, manufactured by Wako Pure Chemical Industries, Ltd.) and heated at a temperature of 100° C. for 1 hour to obtain an alignment film forming composition (1).

(Preparation of the second liquid crystal composition (1))

The polymerizable liquid crystal compound (X3) and the polymerizable liquid crystal compound (X4) shown below are mixed, and the leveling agent, photopolymerization initiator, and ionic compound shown below are added thereto, and then the following are added The mixture was obtained with the solvent shown. The mixture was stirred at a temperature of 80° C. for 1 hour, thereby preparing a second liquid crystal composition (1). The polymerizable liquid crystal compounds (X3) and (X4) are based on Japanese Patent Application Laid-Open It was prepared according to the method described in the Publication No. 2010-244038 and has the structure shown below. The ionic compound has the structure shown below.

Polymerizable liquid crystal compound (X3): 80 parts

Polymerizable liquid crystal compound (X4): 20 parts

Leveling agent [MEGAFACE F-556 (manufactured by DIC Corporation)]: 0.1 part

Photopolymerization initiator [Omnirad907 (manufactured by IGM Resin B.V.)]: 2.5 parts

Ionic compounds: 0.1 parts

Solvent [cyclopentanone]: 650 parts

‧Polymerizable liquid crystal compound (X3):

‧Polymerizable liquid crystal compound (X4):

‧Ionic compounds:

(Preparation of the first liquid crystal retardation layer (1) with base material layer)

A cycloolefin polymer (COP) film (ZF14, manufactured by Japan ZEON Co., Ltd.) cut into a rectangular shape was subjected to corona treatment using a corona treatment device (AGF-B10; manufactured by Kasuga Electric Co., Ltd.), and then coated The alignment film forming composition (1) is heated and dried to form an alignment film with a thickness of 100 nm. The surface of the obtained alignment film was rubbed at an angle of 75° from the longitudinal direction of the COP film, and the second liquid crystal composition (1) was applied thereon with a rod coater. The obtained coating film was dried at a temperature of 120° C. for 2 minutes, and then the exposure amount was 1000 mJ/ under a nitrogen environment at a temperature of 80° C. using a high-pressure mercury lamp ("UNICURE VB-15201BY-A" manufactured by USHIO Electric Co., Ltd.). cm ² (based on 365 nm) of ultraviolet light is irradiated to the dry film to form a hardened material layer of the polymeric liquid crystal compound ( 1-1). Thereby, the first liquid crystal retardation with the base material layer composed of the second base material layer (COP film)/first liquid crystal retardation layer (1) (alignment film/hardened material layer (1-1)) is obtained layer(1).

When the thickness of the obtained hardened material layer (1-1) was measured with a laser microscope, the thickness was 2 μm. The in-plane retardation value of the first liquid crystal retardation layer (1) was measured using KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd. As a result, the in-plane phase difference value at a wavelength of 550 nm is Re (550) = 270 nm. In addition, the retardation value of the COP film at a wavelength of 550 nm is approximately 0, so the COP film does not affect the optical properties of the first liquid crystal retardation layer (1). The alignment angle is -15° relative to the length direction of the COP film.

[Preparation of the second liquid crystal phase difference layer (1)]

(Preparation of the second liquid crystal composition (2))

The second liquid crystal composition was prepared by mixing the polymerizable liquid crystal compound (X5) shown below, a leveling agent, and a photopolymerization initiator, and then mixing the solvent shown below, and stirring at a temperature of 80° C. for 1 hour. Object(2). The polymerizable liquid crystal compound (X5) has a structure shown below.

Polymerizable liquid crystal compound (X5) [Paliocolor LC242 (manufactured by BASF JAPAN Co., Ltd.)]: 100 parts

Leveling agent [BYK-361N (manufactured by BYK-Chemie Co., Ltd.)]: 0.1 part

Photopolymerization initiator [Omnirad907 (manufactured by IGM Resin B.V.)]: 2.5 parts

Solvent [propylene glycol 1-monomethyl ether 2-acetate (PGME)]: 400 parts

‧Polymerizable liquid crystal compound (X5):

(Preparation of the second liquid crystal retardation layer (1) with base material layer)

A rectangular triacetate cellulose (TAC) film (KC4UY manufactured by KONICA MINOLTA Co., Ltd.) was cut out, the alignment film forming composition (1) was applied, and an alignment film with a thickness of 100 nm was formed after heating and drying. The surface of the obtained alignment film was rubbed at an angle of 15° from the longitudinal direction of the TAC film, and the second liquid crystal composition (2) was applied thereon with a rod coater. The obtained coating film was dried at a temperature of 100° C. for 1 minute, and then cooled to room temperature to obtain a dry film. Then, using a high-pressure mercury lamp ("UNICURE VB-15201BY-A" manufactured by USHIO Electric Co., Ltd.), the dry film is irradiated with ultraviolet light with an exposure dose of 1000mJ/cm ² (365nm standard) in a nitrogen environment, thereby forming a polymerizable film. A cured layer (2-1) of a polymerizable liquid crystal compound in which the optical axis of the liquid crystal compound is aligned in a horizontal direction with respect to the TAC film surface. Thereby, a base composed of the second base material layer (TAC film)/second liquid crystal retardation layer (1) (alignment film/cured material layer (2-1)) (horizontal alignment liquid crystal cured film)) is obtained. The second liquid crystal retardation layer (1) of the material layer.

When the thickness of the obtained hardened material layer (2-1) was measured with a laser microscope, the thickness was 1 μm. The in-plane retardation value of the second liquid crystal retardation layer (1) was measured using KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd. As a result, the in-plane phase difference value at a wavelength of 550 nm is Re (550) = 140 nm. In addition, the retardation value of the TAC film at a wavelength of 550 nm is approximately 0, so the TAC film does not affect the optical properties of the second liquid crystal retardation layer (1). The alignment angle is 75° relative to the length direction of the TAC film.

[Preparation of the first liquid crystal phase difference layer (2)]

(Preparation of composition (2) for forming photo-alignment film)

2 parts of a photo-alignment material having the structure shown below and 98 parts of cyclopentanone (solvent) were mixed and stirred at a temperature of 80° C. for 1 hour to obtain a photo-alignment film forming composition (2). The photo-alignment material having the following structure (weight average molecular weight: 50,000, m:n=50:50) was synthesized according to the method described in Japanese Patent Application Laid-Open No. 2021-196514.

Photoalignment materials:

(Preparation of the second liquid crystal composition (3))

The following polymerizable liquid crystal compound (X6), polymerizable liquid crystal compound (X7), leveling agent and photopolymerization initiator were mixed, and N-methyl- was mixed so that the solid content concentration became 13%. 2-pyrrolidinone (NMP), and stirred at a temperature of 80° C. for 1 hour, thereby preparing a second liquid crystal composition (3). The polymerizable liquid crystal compound (X6) and the polymerizable liquid crystal compound (X7) have structures shown below. The polymerizable liquid crystal compound (X6) is prepared in the same manner as the method described in Japanese Patent Application Laid-Open No. 2019-003177. The polymerizable liquid crystal compound (X7) is prepared in the same manner as described in Japanese Patent Application Laid-Open No. 2009-173893.

Polymerizable liquid crystal compound (X6): 90 parts

Polymerizable liquid crystal compound (X7): 10 parts

Leveling agent [BYK-361N (manufactured by BM Chemie Co., Ltd.)]: 0.1 part

Photopolymerization initiator [IRGACURE OXE-03 (manufactured by BASF JAPAN Co., Ltd.)]: 3 parts

‧Polymerizable liquid crystal compound (X6):

‧Polymerizable liquid crystal compound (X7):

1 mg of the polymerizable liquid crystal compound (X6) was dissolved in 10 Ml of chloroform to obtain a solution. The obtained solution was placed in a measurement cell with an optical path length of 1 cm as a measurement sample, and the measurement sample was mounted on a UV-visible spectrophotometer ("UV-2450" manufactured by Shimadzu Corporation) to measure the absorption. spectrum. When the wavelength at which the maximum absorption is obtained is read from the obtained absorption spectrum, the maximum absorption wavelength λmax in the wavelength range of 300 to 400 nm is 356 nm.

(Preparation of the first liquid crystal retardation layer (2) with base material layer)

The photo alignment film forming composition (2) was applied to a biaxially stretched polyethylene terephthalate (PET) film (DIAFOIL, manufactured by Mitsubishi Plastics Co., Ltd.) using a rod coater. The obtained coating layer was dried at a temperature of 120° C. for 2 minutes, and then cooled to room temperature to dry the coating layer. Thereafter, the dried coating layer was irradiated with 100 mJ (313 nm reference) of polarized ultraviolet light using a UV irradiation device (SPOT CURE SP-9; manufactured by USHIO Electric Co., Ltd.) to obtain a photo-alignment film. (2). The thickness of the optical alignment film (2) measured using an ellipsometer M-220 manufactured by JASCO Corporation was 100 nm.

The second liquid crystal composition (3) prepared above is coated on the photo alignment film (2) on the PET film using a rod coater to form a coating layer. The coating layer was heated and dried at a temperature of 120° C. for 2 minutes, and then cooled to room temperature. The dried coating layer was irradiated with ultraviolet light with an exposure dose of 500 mJ/cm ² (365 nm standard) using a high-pressure mercury lamp ("UNICURE VB-15201BY-A" manufactured by USHIO Electric Co., Ltd.) in a nitrogen environment. A cured material layer (1-2) of the second liquid crystal composition (3) is formed in which the polymerizable liquid crystal compound is cured in a state in which the polymerizable liquid crystal compound is aligned in the horizontal direction with respect to the plane of the PET film. The thickness of the hardened material layer (1-2) was measured to be 2 μm using a laser microscope LEXT OLS4100 manufactured by OLYMPUS Co., Ltd. Thereby, the first base material layer-attached layer composed of the second base material layer (PET film)/first liquid crystal retardation layer (2) (photo alignment film (2)/cured material layer (1-2)) is obtained. 1. Liquid crystal retardation layer (2).

Corona treatment was applied to the side of the first liquid crystal retardation layer (2) with the base material layer, and the side with the base material layer was attached through a 25 μm pressure-sensitive adhesive made by LINTEC Corporation. The first liquid crystal retardation layer (2) was bonded to glass, and the PET film was peeled and removed to obtain a test body. The in-plane phase difference value of this test object was measured using KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd. The in-plane phase difference values for light with wavelengths of 450nm, 550nm, and 650nm are determined from the measurement results of the in-plane phase difference values for light with wavelengths of 448.2nm, 498.6nm, 548.4nm, 587.3nm, 628.7nm, and 748.6nm. The obtained Cauchy dispersion formula is calculated. As a result, the in-plane phase difference values are Re (450) = 122 nm, Re (550) = 140 nm, and Re (650) = 144 nm. The relationship between the in-plane phase difference values at each wavelength is as follows.

Re(450)/Re(550)=0.87

Re(650)/Re(550)=1.03

[In the formula, Re(450) represents the in-plane phase difference value for light with a wavelength of 450 nm, Re(550) represents the in-plane phase difference value for the light with a wavelength of 550 nm, and Re(650) represents the in-plane phase difference value for the light with a wavelength of 650 nm. In-plane phase difference value of light]

[Preparation of the second liquid crystal retardation layer (2)]

(Preparation of composition for vertical alignment film formation)

Mix 2-phenoxyethyl acrylate, tetrahydrofuranmethyl acrylate, dipenterythritol triacrylate and bis(2-vinyloxyethyl) ether in a ratio of 1:1:4:5, and further LUCIRIN TPO as a polymerization initiator was added at a proportion of 4% to prepare a composition for forming a vertical alignment film.

(Preparation of the second liquid crystal composition (4))

The second liquid crystal composition (4) is prepared by preparing a photopolymerizable nematic liquid crystal compound (RMM28B manufactured by MERCK Corporation) and a solvent so that the solid content becomes 1 to 1.5 g. The solvent is made by mixing methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), and cyclohexanone (CHN) in a mass ratio (MEK: MIBK: CHN) of 35:30:35. of mixed solvents.

(Preparation of the second liquid crystal retardation layer (2) with base material layer)

Roll-shaped release polyethylene terephthalate (PET) film with a film width of 800 mm ("FF-50" manufactured by UNITIKA Co., Ltd., single-sided release-treated PET film (thickness of support substrate: 50 μm)) After subjecting the surface opposite to the release-treated surface to corona treatment, use a slit die coater to apply the composition for forming the vertical alignment film obtained above so that the thickness after hardening becomes 3 μm. things. The coating film is irradiated with ultraviolet light of 200mJ/ ^cm2 to form a vertical alignment film on the single-sided release-treated PET film.

On the vertical alignment film on the single-sided release-treated PET film, use a slit die coater to apply the second liquid crystal composition (4) prepared above so that the thickness after hardening becomes 1 μm. . The drying temperature was set to 75° C. and the drying time was set to 120 seconds. After drying the coating layer, ultraviolet (UV) was irradiated to polymerize the polymerizable liquid crystal compound to form a cured material layer (2-2). Thereby, a base material layer-attached film composed of the second base material layer (single-sided release-treated PET film)/the second liquid crystal retardation layer (2) (vertical alignment film/cured material layer (2-2)) is obtained. The second liquid crystal retardation layer (2). The second liquid crystal retardation layer (2) is a positive C plate.

[Preparation of active energy ray curable composition (1) (cationically polymerizable adhesive composition)]

The components shown below are mixed and then defoamed to prepare an active energy ray curable composition (1). In addition, the photocationic polymerization initiator is prepared as a 50% propylene carbonate solution, and its parts are expressed in solid parts.

‧Cationic polymerizable compound (1) [3-ethyl-3{[(3-ethyloxetan-3-yl)methoxy]methyl}oxetane (trade name: OXT- 221. East Asia Synthetic Co., Ltd.)]: 60.0 shares

‧Cationic polymerizable compound (2) [3,4-epoxycyclohexanecarboxylic acid 3',4'-epoxycyclohexylmethyl ester (trade name: CEL2021P, manufactured by DAICEL Co., Ltd.)]: 32.5 share

‧Cationically polymerizable compound (3) [1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol (Trade name: EHPE3150, manufactured by DAICEL Co., Ltd.)]: 7.5 servings

‧Photocationic polymerization initiator [CPI-100P (manufactured by SUNAPRO Co., Ltd., 50% by mass solution)]: 2.3 parts

‧Photosensitizer [9,10-dibutoxyanthracene]: 1.0 parts

‧Photosensitizing additive [1,4-diethoxynaphthalene]: 1.0 parts

[Preparation of active energy ray curable composition (2) (radically polymerizable adhesive composition)]

The components shown below were mixed to prepare an active energy ray curable composition (2).

‧N,N-dimethylacrylamide [manufactured by KJ CHEMICALS Co., Ltd.]: 65 parts

‧Dicyclopentenyl acrylate [Hitachi Chemical Industry Co., Ltd.]: 15 parts

‧Ultraviolet curable urethane acrylate resin [trade name: UV-3700B, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., viscosity: 30,000 to 60,000mPa‧s/60℃, molecular weight (Mw): 38,000, oligomer Number of functional groups: 2, glass transition temperature Tg: -6℃]: 20 parts

‧Photoradical polymerization initiator [Omnirad 819 (2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylpropan-1-one), BASF JAPAN Co., Ltd.] :3 copies

[Preparation of adhesive layer (1)]

In a reaction vessel equipped with a mixer, a thermometer, a reflux cooler, a dropping device and a nitrogen introduction pipe, fill 95.0 parts of n-butyl acrylate, 4.0 parts of acrylic acid, 1.0 part of 2-hydroxyethyl acrylate, and 200 parts of ethyl acetate. and 0.08 parts of 2,2'-azobisisobutyronitrile, and replace the air in the above reaction vessel with nitrogen. The reaction solution was heated to 60° C. while stirring in a nitrogen environment. After reacting for 6 hours, the reaction solution was cooled to room temperature.

When the weight average molecular weight of a part of the obtained solution was measured, it was confirmed that 1.8 million (meth)acrylate polymers were produced. The weight average molecular weight (Mw) of the (meth)acrylic resin is a polystyrene-equivalent weight average molecular weight measured using gel permeation chromatography (GPC) under the following conditions.

[Measurement conditions]

‧GPC measuring device: Made by TOSOH Co., Ltd., HLC-8020

‧GPC column (passed in the following order): Made by TOSOH Co., Ltd.

TSK guard column HXL-H

TSK gel GMHXL(×2)

TSK gel G2000HXL

‧Measurement solvent: tetrahydrofuran

‧Measurement temperature: 40℃

100 parts of the (meth)acrylate polymer obtained in the above step (solid content conversion value; the same below) and trimethylolpropane-modified toluene diisocyanate (manufactured by TOSOH Co., Ltd.) as an isocyanate-based cross-linking agent were mixed. , trade name "CORONATE (registered trademark) L") 1.5 parts, 0.30 parts of 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name "KBM403") as a silane coupling agent , 7.5 parts of ethoxylated isocyanate triacrylate (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.: product name "A-9300") as an ultraviolet curable compound, and 2-methyl as a photopolymerization initiator 0.5 part of methyl-1-(4-methylthiophenyl)-2-morpholinylpropan-1-one (BASF: IRGACURE (registered trademark) 907), stir thoroughly and dilute with ethyl acetate, Thereby, a coating solution of the adhesive composition (1) is obtained.

On the release treatment surface (peel layer) of the separation membrane (LINTEC Co., Ltd.: SP-PLR382190), use a thin coater to achieve a thickness of 5 μm after drying (using a digital micrometer produced by NIKON Co., Ltd. "MH-15M" method), after applying the coating solution of the adhesive composition (1), drying it for 1 minute at a temperature of 100°C, the surface of the separation membrane with the dried coating layer is On the opposite side, another separation membrane (manufactured by LINTEC Co., Ltd.: SP-PLR381031) is attached. The coating layer was irradiated with ultraviolet rays (irradiation intensity 500 mW/cm ² , cumulative light amount 500 mJ/cm ² ) through the release sheet using an ultraviolet irradiation device with a conveyor belt (manufactured by FUSION UV SYSTEMS, D BULB was used as the lamp system) to form adhesion. The adhesive layer (1) is obtained to obtain an adhesive layer (1) with separation membranes on both sides.

When measuring the water vapor penetration of the adhesive layer (1) using a water vapor penetration measuring machine ("Lyssy-L80-5000" manufactured by Lyssy Corporation) at a temperature of 40°C and a relative humidity of 90%, the water vapor penetration Vapor penetration is 7600g/(m ² ‧24h).

When the storage elastic coefficient G’ of the adhesive layer (1) was measured, it was 125,000 Pa at a temperature of 25°C. The storage elastic coefficient G' is measured by laminating a plurality of adhesive layers (1) with a thickness of 0.2 mm (measured with a digital micrometer "MH-15M" manufactured by NIKON Co., Ltd.), and then laminating a layer of 8 mm in diameter. The punched cylinder was used as a measurement sample, and the measurement sample was measured according to JIS K7244-6 using a viscoelasticity measuring device (MCR300 manufactured by Physica Corporation) by the torsional shear method under the following conditions.

[Measurement conditions]

Normal force FN: 1N

Deformation γ: 1%

Frequency: 1Hz

Temperature: 25℃

When measuring the glass transition temperature of the adhesive layer (1) according to the following procedure, the glass transition temperature is below 25°C. First, take 5 mg of the adhesive layer (1), place it in an aluminum squeeze lid type container, press it and seal it tightly, and prepare a sample for measurement. In the differential scanning calorimeter (DSC) ["EXSTAR-6000 DSC6220" sold by SII NANOTECHNOLOGY Co., Ltd. Install a container containing the above-mentioned measurement sample, and while expelling nitrogen, cool down from 20°C to -60°C. After reaching -60°C, keep it for 1 minute, then raise the temperature from -60°C to 150°C at a heating rate of 10°C/min. ℃, and immediately cool down to 20℃ after reaching 150℃. Next, the DSC curve when the temperature is raised from -60°C to 150°C is used to determine the intermediate point glass transition temperature specified in JIS K 7121-1987 "Measurement method of transition temperature of plastics", and use this as the adhesive layer to be measured ( 1) glass transition temperature.

[Preparation of adhesive layers (2) to (4)]

In a reaction vessel equipped with a mixer, a thermometer, a reflux cooler, a dropping device and a nitrogen introduction pipe, fill 97.0 parts of n-butyl acrylate, 1.0 part of acrylic acid, 0.5 part of 2-hydroxyethyl acrylate, and 200 parts of ethyl acetate. and 0.08 parts of 2,2'-azobisisobutyronitrile, and replace the air in the above reaction vessel with nitrogen. The reaction solution was heated to 60° C. while stirring in a nitrogen atmosphere, and after reacting for 6 hours, the reaction solution was cooled to room temperature. After measuring the weight average molecular weight of a part of the obtained solution according to the above procedure, it was confirmed that 1.8 million (meth)acrylate polymers were produced.

100 parts of the (meth)acrylate polymer obtained in the above step (solid content conversion value; the same below) and trimethylolpropane-modified toluene diisocyanate (manufactured by TOSOH Co., Ltd.) as an isocyanate-based cross-linking agent were mixed. , trade name "CORONATE (registered trademark) L") 0.30 parts, 0.30 parts of 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name "KBM403") as a silane coupling agent , stir thoroughly and dilute with ethyl acetate to obtain a coating solution of the adhesive composition (2).

On the release surface (peeling layer) of the separation membrane (manufactured by LINTEC Co., Ltd.: SP-PLR382190), use a thin coater to apply a thin coater to the thickness after drying to 15 μm (adhesive layer (2)) and 25 μm (adhesive layer). agent layer (3)), and 35μm (adhesive layer (4)) (the thickness is based on (measured with a digital micrometer "MH-15M" manufactured by NIKON Co., Ltd.), after applying the coating solution of the adhesive composition (2), dry it at a temperature of 100°C for 1 minute, and then dry it after bonding. The surface of the separation membrane of the coating layer is the opposite side, and another separation membrane (manufactured by LINTEC Co., Ltd.: SP-PLR381031) is attached to obtain adhesive layers (2) to (4) with separation membranes on both sides.

When the storage elastic coefficient G’ of the adhesive layers (2) to (4) was measured according to the above procedure, they were all 25500Pa at a temperature of 25°C. Moreover, when the glass transition temperatures of the adhesive layers (2) to (4) were measured according to the above procedure, the glass transition temperatures were all 25°C or less.

[Example 1]

(Preparation of retardation laminated body (1) with base material layer)

The first liquid crystal retardation layer side (1) of the first liquid crystal retardation layer (1) with a base material layer obtained above, and the second liquid crystal phase of the second liquid crystal retardation layer (1) with a base material layer Corona treatment is applied to the difference layer (1) side respectively. The adhesive layer (1) obtained by peeling off the separation film of the adhesive layer (1) with separation films attached to both sides is bonded to the corona-treated surfaces through the adhesive layer (1) to obtain the phase of the base material layer. Difference laminated body (1) (phase difference body (1)). The retardation laminated body with a base material layer (1) has a second base material layer (COP film)/first liquid crystal retardation layer (1) (alignment film/cured material layer (1-1))/second layer The layer structure of the combined layer (adhesive layer (1))/second liquid crystal retardation layer (1) (hardened material layer (2-1)/alignment film)/second base material layer (TAC film).

(Preparation of optical laminate (1) with separation film)

From the long polarizing plate with a base material layer (1) obtained above, the polarizing plate with a base material layer (1) is cut out so that the length direction of the strip becomes the long side, and the polarizing plate with the base material layer (1) is cut out. The coating layer side of the polarizing plate (1) is corona treated. Then, the second base material layer (COP film) on the first liquid crystal retardation layer (1) side of the retardation laminate with base material layer (c1) obtained above is peeled off, and the peeled surface is subjected to corona treatment. The alignment film is also peeled off together with the peeling off of the second base material layer. The corona-treated surfaces are bonded together through the active energy ray curable composition (1) prepared above so that their long sides overlap each other. Then, ultraviolet rays are irradiated from the side of the polarizing plate (1) with the base material layer so that the accumulated light amount of UVA becomes about 350 mJ/cm ² (measurement value obtained with a measuring device: UV Power PuckII manufactured by FusionUV Corporation) to activate the The energy ray curable composition (1) is hardened to form the first bonding layer which is a hardened material layer. The thickness of the first bonding layer is 2 μm.

After that, the second base material layer (TAC film) of the second liquid crystal retardation layer (1) with the base material layer is peeled off and exposed, and the adhesive layer (2) with the release film attached on both sides is bonded and peeled off. The adhesive layer (2) exposed by the separation film is peeled off from the single-sided release-treated PET film on the side of the polarizing plate (1) with the base material layer, to obtain an optical laminate (1) with a separation film. The alignment film is also peeled off together with the peeling off of the second base material layer. The optical laminated body (1) with a release film has a protective layer (HC layer)/liquid crystal polarizer (photo alignment film (1)/cured material layer)/covering layer/first bonding layer (active energy ray curable composition) Hardened material layer of object (1))/1st liquid crystal retardation layer (1) (hardened material layer (1-1))/2nd laminating layer (adhesive layer (1))/2nd liquid crystal retardation layer The layer structure of (1) (hardened material layer (2-1))/third bonding layer (adhesive layer (2))/separation membrane.

[Example 2]

In addition to laminating the polarizing plate (1) with a base material layer and the retardation laminate (1) with a base material layer via the active energy ray curable composition (2), in order to make the active energy ray curable composition (2) Hardening was performed in the same manner as in Example 1, except that ultraviolet rays were irradiated so that the cumulative amount of UVB light became approximately 250 mJ/cm ² (measurement value obtained with a measuring device: UV Power PuckII manufactured by FusionUV Corporation). An optical laminated body (2) with a separation film was obtained.

[Example 3]

(Preparation of phase difference laminate (3) with base material layer)

The first liquid crystal retardation layer side (2) of the first liquid crystal retardation layer (2) with a base material layer obtained above, and the second liquid crystal phase of the second liquid crystal retardation layer (2) with a base material layer Corona treatment is applied to the difference layer (2) side respectively. On the corona-treated surface, the adhesive layer (1) obtained by peeling off the adhesive layer (1) with the separation film on both sides is bonded together to obtain a phase difference laminate (3) with a base material layer. Difference body (3)). The retardation laminated body (3) with a base material layer has a second base material layer (PET film)/first liquid crystal retardation layer (2) (photo alignment film (2)/hardened material layer (1-2)) / 2nd laminating layer (adhesive layer (1)) / 2nd liquid crystal retardation layer (2) (hardened material layer (2-2) / vertical alignment film) / 2nd base material layer (single-sided release treatment) PET film) layer structure.

(Preparation of optical laminate (3) with separation film)

Corona treatment is performed on the coating layer side of the polarizing plate (1) with a base material layer obtained above. Then, the second base material layer (PET film) on the first liquid crystal retardation layer (2) side of the retardation laminate with base material layer (3) obtained above is peeled off, and the peeled surface is subjected to corona treatment. During the peeling of the second base material layer, the PET film is peeled off, but the photo-alignment film (2) is not peeled off and remains on the cured material layer (1-2). The corona-treated surfaces are bonded together via the active energy ray curable composition (2) prepared above. Then, ultraviolet rays are irradiated from the side of the polarizing plate (1) with the base material layer so that the accumulated light amount of UVA becomes about 250 mJ/cm ² (measurement value obtained with a measuring device: UV Power PuckII manufactured by FusionUV Corporation) to activate the The energy ray curable composition (2) is hardened to form the first bonding layer which is a hardened material layer. The thickness of the first bonding layer is 2 μm.

After that, on the exposed surface of the second liquid crystal retardation layer (2) with the base layer attached by peeling off the second base layer (single-sided release treated PET film), an adhesive layer (2) with release films attached from both sides is bonded. 2) Peel off the adhesive layer (2) exposed by one of the separation films, and peel off the single side of the polarizing plate (1) with the base material layer The PET film is subjected to release treatment to obtain an optical laminated body (3) with a release film. By peeling off the second base material layer, the single-sided release-treated PET film is peeled off, and the vertical alignment film is not aligned and remains on the hardened material layer (2-2). The optical laminated body (3) with a release film has a protective layer (HC layer)/liquid crystal polarizer (photo alignment film (1)/cured material layer)/covering layer/first bonding layer (active energy ray curable composition) Hardened material layer of object (2))/first liquid crystal retardation layer (2) (photo alignment film (2)/hardened material layer (1-2))/second laminating layer (adhesive layer (1)) /Layer structure of the second liquid crystal retardation layer (2) (hardened material layer (2-2)/vertical alignment film)/third laminating layer (adhesive layer (2))/separation film.

[Examples 4 to 6]

Except for using those shown in Tables 2 and 3 as the polarizing plate with a base material layer and the third lamination layer, the same procedure as in Example 3 was carried out to obtain optical laminates (4) to (4) with a separation film. 6).

[Example 7]

Except using what is shown in Table 3 as the third bonding layer, the same procedure as in Example 2 was carried out to obtain an optical laminated body (7) with a release film.

[Comparative example 1]

(Preparation of adhesive composition)

After mixing the components shown below, the mixture is defoamed to prepare a cationically polymerizable adhesive composition. The cationic polymerization initiator is prepared as a 50 mass% propyl carbonate solution, and its solid content is shown.

‧1,6-Hexanediol Diglycidyl Ether (EX-212L, manufactured by NAGASE CHEMTEX Co., Ltd.): 25 parts

‧4-hydroxybutyl vinyl ether: 10 parts

‧Bisphenol F epoxy resin (EXA-830CRP, manufactured by DIC Co., Ltd.): 65 parts

‧Cationic polymerization initiator (CPI-100P, manufactured by SUNAPRO Co., Ltd., 50 mass% solution): 3 parts

(Preparation of retardation laminated body (c1) with base material layer)

The first liquid crystal retardation layer (2) with a base material layer and the second liquid crystal retardation layer (2) with a base material layer obtained above are placed on the first liquid crystal retardation layer side (2) side and the second liquid crystal retardation layer side (2) respectively. The liquid crystal retardation layer (2) is laminated via the active energy ray curable composition (1) prepared above so that the liquid crystal retardation layer (2) side becomes the bonding surface. Then, ultraviolet rays are irradiated from the side of the second liquid crystal retardation layer (2) with the base material layer to harden the active energy ray curable composition (1) to form a second bonding layer with a thickness of 2 μm, thereby obtaining the base material layer. phase difference layered body (c1) (phase difference body (c1)). The retardation laminated body with a base material layer (c1) has a second base material layer (PET film)/first liquid crystal retardation layer (2) (photo alignment film (2)/cured material layer (1-2)) /Second bonding layer (cured material layer of active energy ray curable composition (1))/Second liquid crystal retardation layer (2) (cured material layer (2-2)/vertical alignment film)/Second base The layer structure of the material layer (single-sided release treated PET film).

(Preparation of optical laminate (c1) with separation film)

Corona treatment is performed on the coating layer side of the polarizing plate (1) with a base material layer obtained above. Then, the second base material layer (PET film) on the first liquid crystal retardation layer (2) side of the retardation laminate with base material layer (c1) obtained above was peeled off, and corona treatment was performed on the peeling surface. During the peeling of the second base material layer, the PET film is peeled off, but the photo-alignment film (2) is not peeled off and remains on the cured material layer (1-2). The corona-treated surfaces are bonded to each other through the adhesive layer (1) obtained by peeling off the release film of the adhesive layer (1) with release films attached to both surfaces, and a laminated structure (c1) is obtained.

A cycloolefin polymer (COP) film (ZF14, manufactured by Japan ZEON Co., Ltd.) with a thickness of 13.00 μm, and the single side of the polarizing plate (1) side with the base layer of the laminated structure (c1) obtained above were Release treatment: The exposed surface of the PET film is peeled off and subjected to corona treatment. The corona-treated surfaces were bonded together through the adhesive composition prepared above, and an ultraviolet irradiation device (SPOT CURE SP-7, manufactured by USHIO Electric Co., Ltd.) was used to irradiate with an exposure dose of 500 mJ/cm ² (365 nm standard). UV rays form an adhesive layer with a thickness of 2.00μm. The ultraviolet rays are irradiated from the COP film side. After that, on the surface of the second liquid crystal retardation layer (2) with the base material layer peeled off and exposed, a separation film separated from one of the adhesive layers (2) with separation films attached on both sides is bonded. The exposed adhesive layer (2) is used to obtain an optical laminate (c1) with a separation film. By peeling off the second base material layer, the single-sided release-treated PET film is peeled off, and the vertical alignment film is not aligned and remains on the hardened material layer (2-2). The optical laminated body (c1) with a release film has a protective layer (COP film/adhesive layer/HC layer)/liquid crystal polarizer (photo alignment film (1)/hardened material layer)/covering layer/first bonding layer (Adhesive layer (1))/1st liquid crystal retardation layer (2) (photo alignment film (2)/hardened material layer (1-2))/2nd laminating layer (active energy ray curable composition ( 1) hardened material layer)/second liquid crystal retardation layer (2) (hardened material layer (2-2)/vertical alignment film)/third laminating layer (adhesive layer (2))/separation film layer structure.

[Comparative example 2]

In addition to using a triacetyl cellulose (TAC) film (KC2CT, manufactured by KONICA MINOLTA Co., Ltd.) with a thickness of 20.00 μm in place of the COP film, and peeling the TAC film and the single-sided release-treated PET film from the laminated structure (c1), The exposed surfaces were bonded and ultraviolet rays were irradiated from the TAC film side, and the optical laminated body with a separation film (c2) was obtained according to the manufacturing procedure of the optical laminated body with a separation film (c2) in Comparative Example 1.

[Comparative example 3]

From the long polarizing plate with a base material layer (1) obtained above, cut out the long polarizing plate (1) with a base material layer in such a way that the length direction of the strip becomes the long side. (1) Corona treatment is performed on the coating side. Then, the retardation laminated body with the base material layer obtained by the procedure of Example 1 was used. (1) The second base material layer (COP film) on the side of the first liquid crystal retardation layer (1) is peeled off, and the peeled surface is subjected to corona treatment. The alignment film is also peeled off together with the peeling off of the second base material layer. The adhesive layer (1) obtained by peeling off the separation film of the adhesive layer (1) with the separation film attached to both sides is pasted across the adhesive layer (1) so that the corona-treated surfaces overlap each other with their long sides. combine.

After that, the second base material layer (TAC film) of the second liquid crystal retardation layer (1) with the base material layer is peeled off and the exposed surface is bonded to the adhesive layer (3) with the release film attached on both sides, and one of them is peeled off. The adhesive layer (3) exposed by the separation film is peeled off the single-sided release-processed PET film on the side of the polarizing plate (1) with the base material layer, and an optical laminate (c3) with a separation film is obtained. The alignment film is also peeled off together with the peeling off of the second base material layer. The optical laminate with a release film (c3) has a protective layer (HC layer)/liquid crystal polarizer (photo alignment film (1)/hardened material layer)/covering layer/first bonding layer (adhesive layer (1) )/1st liquid crystal retardation layer (1) (hardened material layer (1-1))/2nd laminating layer (adhesive layer (1))/2nd liquid crystal retardation layer (1) (hardened material layer ( 2-1))/The third laminating layer (adhesive layer (3))/layer structure of the separation membrane.

[Comparative Example 4]

The coating layer side of the polarizing plate (1) with a base material layer obtained above is subjected to corona treatment. Then, the second base material layer (PET film) on the first liquid crystal retardation layer (2) side of the retardation laminate with base material layer (3) obtained by the procedure of Example 3 was peeled off, and the peeled surface was Corona treatment. During the peeling of the second base material layer, the PET film is peeled off, but the photo-alignment film (2) is not peeled off and remains on the cured material layer (1-2). The above-mentioned corona-treated surfaces are bonded to each other through the adhesive layer (1) obtained by peeling off the adhesive layer (1) with the release film attached on both sides.

After that, on the exposed surface of the second liquid crystal retardation layer (2) with the base layer attached by peeling off the second base layer (single-sided release treated PET film), an adhesive layer (2) with release films attached from both sides is bonded. 3) Peel off the adhesive layer (3) exposed by one of the separation films, and peel off the single side of the polarizing plate (1) with the base material layer The PET film was subjected to release treatment to obtain an optical laminated body with a release film (c4). By peeling off the second base material layer, the single-sided release-treated PET film is peeled off, and the vertical alignment film is not aligned and remains on the hardened material layer (2-2). The optical laminated body with a release film (c4) has a protective layer (HC layer)/liquid crystal polarizer (optical alignment film (1)/hardened material layer)/covering layer/first bonding layer (adhesive layer (1) )/1st liquid crystal retardation layer (2) (photo alignment film (2)/hardened material layer (1-2))/2nd laminating layer (adhesive layer (1))/2nd liquid crystal retardation layer ( 2) The layer structure of (hardened material layer (2-2)/vertical alignment film)/third laminating layer (adhesive layer (3))/separation film.

[Comparative example 5]

The first liquid crystal retardation layer (2) with a base material layer and the second liquid crystal retardation layer (2) with a base material layer obtained above are placed on the first liquid crystal retardation layer side (2) side and the second liquid crystal retardation layer side (2) respectively. 2 The liquid crystal retardation layer (2) is laminated via the active energy ray curable composition (2) so that the side becomes the bonding surface. Then, ultraviolet rays are irradiated from the side of the second liquid crystal retardation layer (2) of the layer with a base material to harden the active energy ray curable composition (2) to form a second bonding layer with a thickness of 2 μm, thereby obtaining a layer with a base material. Phase difference laminate of layers (c5).

It was the same as Comparative Example 4, except that the retardation laminated body with a base material layer (c5) was used instead of the retardation laminated body with a base material layer (3), and the one shown in Table 5 was used as the third bonding layer. This was performed to obtain an optical laminate (c5) with a separation film.

[Comparative Example 6]

Except that the laminated structure (c1) produced by the procedure of Comparative Example 1 was used instead of the retardation laminated body (3) with the base material layer, and the ones shown in Table 5 were used as the third bonding layer, the rest were the same as those for comparison. The same procedure was carried out as in Example 4, and an optical laminated body (c6) with a separation film was obtained.

[Calculation of the ratio of the thickness of the adhesive layer (Dt/D1)]

Let the distance from the surface of the protective layer on the opposite side to the liquid crystal polarizer side to the surface of the third bonding layer on the opposite side to the second liquid crystal retardation layer be D1 (Figure 1). Let the total thickness of the layer (adhesive layer) with a Tg of 25°C or less among the laminating layer, the second bonding layer, and the third bonding layer be Dt, and calculate the thickness ratio [%] (=Dt/D1×100 ). When the cured material layer of the active energy ray curable composition (1) and the cured material layer of the active energy ray curable composition (2) were measured according to the above procedure, both exceeded 25°C. In the embodiment, the total thickness Dt is the total thickness D2 of the thickness of the second bonding layer and the thickness of the third bonding layer. The results are shown in Tables 2 to 5.

[Damp heat test]

The optical laminate with a release film obtained above was cut into a size of 30 mm × 30 mm, and the third bonding layer exposed by peeling off the release film was bonded with alkali-free glass (EAGLE XG (registered trademark) manufactured by CORNING Co., Ltd., thickness 0.7mm) as the test sample. The test sample was set up in a spectrophotometer (V7100 manufactured by Japan Spectroscopic Co., Ltd.) with the protective layer side becoming the incident surface, and the visual sensitivity-corrected transmittance of the transmitted light in the direction parallel to the transmission axis of the liquid crystal polarizer was measured. This is the initial visual sensitivity correction transmittance Ty _p 0.

Next, a moist heat test was performed in which the test sample was placed in an oven set at a temperature of 65°C and a relative humidity of 90% and left to stand for 500 hours, and the test sample was taken out from the oven. After that, the test sample is allowed to stand for 6 hours in an environment with a temperature of 25°C and a relative humidity of 55%. The same procedure as above is performed on the test sample to measure the transmission axis parallel to the liquid crystal polarizer. The visual sensitivity corrected transmittance of the transmitted light in the direction is used as the visual sensitivity corrected transmittance Ty _p 1 after the heat and humidity test. Calculate the difference ΔTy _p (=Ty _p 1-Ty _p 0) between the visual sensitivity corrected transmittance Ty _p 1 after the damp heat test and the initial visual sensitivity corrected transmittance Ty _p 0, and evaluate based on the following standards.

A: The difference △Ty _p is more than 0% and less than 1%.

B: The difference △Ty _p is more than 1% and less than 3%.

C: The difference △Ty _p is more than 3%.

[Scratch test]

Using the optical laminate with a release film obtained above, one hour after forming the second bonding layer, and 30 minutes after forming the first bonding layer between the polarizing plate and the first liquid crystal retardation layer, the above-mentioned impact resistance was Prepare test specimens according to the procedures described in the sex test. A load of 5N was applied to the surface of the optical laminated body side of the test sample (the surface of the protective layer side) with a scratch-type hardness tester (manufactured by Erichsen, Germany, model 318, ball diameter 0.75mm) while maintaining the load. One side moves on the above surface at a speed of 1cm/s. After that, under the illumination and reflection conditions of the fluorescent lamp shown in Table 1, observe the protective layer side of the optical laminate of the test sample from the front direction and the oblique direction. Depending on whether scratches are recognized, proceed as follows: The benchmarks shown in Table 1 are evaluated. The results are shown in Tables 2 to 5. In addition, the following evaluations A to D are within the allowable range for actual use.

[Table 1]

[Flexibility test (1): Evaluation of reflective hue]

From the optical laminate with a separation film obtained above, use a super cutter to cut out a small rectangular test piece with a long side of 110 mm and a short side of 10 mm so that the absorption axis of the liquid crystal polarizer becomes parallel to the long side.

As shown in Figure 2(a), in a bending testing machine having two individually movable clamps 501 and 502, the test piece 500 is bent so that the protective layer side of the test piece 500 becomes inside and the bending axis is parallel to the short side. 500 is in a bent state, and the ends of the long sides of the test piece 500 are respectively fixed to the clamps 501 and 502 with adhesive tapes, and the positions of the clamps 501 and 502 are adjusted so that the distance L between the clamps 501 and 502 becomes 70 mm. Thereafter, as shown in FIG. 2(b) , the jig 501 is moved in the direction of arrow A so that the distance L becomes 4.0 mm (bending radius 2R) to further bend the test piece 500 , and then the jig 501 is moved in the direction of arrow A. A series of movements in the direction of B to return the distance L to 70mm is counted as one time. In an environment with a temperature of 25°C and a relative humidity of 55%, the above movements are continuously repeated 100,000 times. The moving speed of the clamp 501 is 1.32m/second, and the time required to repeat the above action of changing the interval L 100,000 times is 27.8 hours. After repeating the above operation 100,000 times, take out the test piece 500 from the bending tester, release the bend of the test piece 500, peel off the separation film to expose the third bonding layer, and bond the PET film with an aluminum vapor deposition film ( The surface of the aluminum vapor-deposited film (manufactured by TORAY Film Processing Co., Ltd., trade name "#50 DMS (X42)") is made into a bonded body. Check the front view from the protective layer side of the bonded body to see if there is any uneven reflection hue along the bending axis, and evaluate based on the following criteria. The results are shown in Tables 2 to 5.

A: Uneven reflection hue is not recognized.

B: The uneven reflection hue is not noticeable, but is recognized.

C: The uneven reflection hue is obvious.

[Flexibility test (2): Evaluation of peeling of the third bonding layer]

From the optical laminate with a separation film obtained above, use a super cutter to cut out rectangular pieces with a long side of 110 mm and a short side of 10 mm so that the absorption axis of the liquid crystal polarizer becomes parallel to the long side. The separation film was peeled off from the small piece to expose the third bonding layer, and an aluminum vapor-deposited PET film (trade name "#50 DMS (X42)" manufactured by TORAY Film Processing Co., Ltd.) with an aluminum vapor-deposited film was bonded to the exposed surface. The face side serves as a test piece.

In addition to using this test piece, the bending testing machine used in the bending test (1) was used, and the action of changing the interval L was repeated 100,000 times under the conditions described in the bending test (1). After repeating the above operation 100,000 times, release the bending of the test piece taken out from the bending testing machine, and confirm whether the third bonding layer has peeled off from the front of the protective layer side of the test piece, and evaluate based on the following standards. When the third bonding layer peels off, the peeling occurs from the end of the test piece, so the size of the peeling is defined as from the end of the test piece where peeling occurs to the side opposite to the end of the peeled test piece. the shortest distance. The results are shown in Tables 2 to 5.

A: Peeling of the third bonding layer was not confirmed.

B: Peeling of the third bonding layer with a size less than 100 μm was confirmed.

C: Peeling of the third bonding layer with a size of 100 μm or more was confirmed.

[Processability test]

A surface protective film is attached to the surface of the protective layer side of the optical laminate with a release film obtained above, and this is cut into a rectangular shape such that the absorption axis of the liquid crystal polarizer becomes +45° with respect to the long side, and is used for processing. Sample. The surface protective film is a film that is releasably attached to the protective layer and can be peeled off while maintaining the shape of the optical laminate to which the release film is attached.

In the processability test, the end surface processing device was used for polishing processing, and whether cracks occurred in the first liquid crystal retardation layer and the second liquid crystal retardation layer on the polished end surface was observed. The end surface processing device will be described based on FIG. 3 . Fig. 3 is a schematic cross-sectional view schematically showing the end face processing device. In the end surface processing device, the laminate W of the sample for processing can be polished by a device provided with the support part 50 and the two rotating tools 60 . The support part 50 is used for fixing, etc., in such a manner that the laminated object W is pressed from above and below so that the laminated object W itself does not move during the polishing process and the overlapped processing sample does not shift. By. The rotary tool 60 is used for grinding the end surface of the laminated material W, and can be rotated around the rotation axis R. The support part 50 may be provided with: a flat base plate (a moving means for the laminated object W) 51; a door-shaped frame 52 disposed on the base plate 51; and a rotary device disposed on the base plate 51 and capable of rotating around a central axis. Table 53; a piston (Cylinder) 54 located in a position opposite to the rotating table 53 in the frame 52 and capable of moving up and down. The laminated object W is clamped and fixed via the clamping frame 55 by the rotating table 53 and the piston 54 . On both sides of the base plate 51, two rotating tools 60 are arranged facing each other. The rotary tool 60 is movable in the direction of the rotation axis R according to the size of the laminated object W, and the substrate 51 is movable so as to pass between the two rotary tools 60 . During the grinding process, the laminated product W is fixed to the support part 50 and the position of the rotating tool 60 in the direction of the rotation axis is appropriately adjusted. Then, while the rotating tool 60 is rotated around the rotation axis R, the laminated product W moves the substrate 51 between the opposing rotating tools 60 . Thereby, it is possible to perform a grinding process in which the rotating tool 60 is moved relative to the laminated object W in a direction parallel to the end surface of the laminated object W and orthogonal to the laminating direction. The grinding blade provided is in contact with the exposed end surfaces facing each other of the laminate W to grind these end surfaces.

Using the end surface processing device shown in Figure 3 and the grinding conditions shown below, the sample for processing was ground into a rectangle of 120 mm × 50 mm (planar view).

Number of laminated samples for processing when performing grinding processing: 100 pieces

The clamping pressure of the laminate W for grinding by extrusion from both sides: 0.1MPa

Relative movement speed between the laminated object W and the rotating tool 60: 3500mm/min

Rotary speed of rotary tool 60: 5400rpm

Conveying pitch (the value calculated by dividing the relative movement speed by the rotational speed of the rotating tool 60 and the number of times the grinding blade contacts the end face when the rotating tool 60 performs one rotation): 0.32mm

Grinding blade entry direction: The end surface of the processing sample is directed from the separation membrane side to the surface protection film side and the grinding blade entry direction

From the processing sample after the polishing process, a PET film with an aluminum vapor deposition film (trade name "#50 DMS (X42)" manufactured by TORAY Film Processing Co., Ltd.) was bonded to the third bonding layer exposed by peeling off the separation film. Aluminum is deposited on the film side to form a bonded body. Using an optical microscope VHX-1000 (manufactured by Keyence Corporation) from the protective layer side of the bonded body, evaluation was performed based on the following standards. The size of the crack is set as the diameter of a true circle inscribed in the crack when viewed from above on the protective layer. The results are shown in Tables 2 to 5.

A: No cracks were observed.

B: Cracks with a size of less than 200 μm were observed.

C: Cracks with a size of 200 μm or more are observed.

[Table 2]

[table 3]

[Table 4]

[table 5]

1: Optical laminated body

10:Polarizing plate

11:Protective layer

15:LCD polarizer

18: Covering layer (second protective layer)

21: 1st liquid crystal phase difference layer

22: Second liquid crystal phase difference layer

31: 1st laminating layer

32: 2nd laminating layer

33: The third laminating layer

38:Separation membrane

Claims (5)

An optical laminate including a protective layer, a liquid crystal polarizer, a first bonding layer, a first liquid crystal retardation layer, a second bonding layer, a second liquid crystal retardation layer, and a third bonding layer in this order, wherein , The liquid crystal polarizing element includes a cured material layer of a first liquid crystal composition, and the cured material layer of the first liquid crystal composition contains a dichroic dye and a polymerizable liquid crystal compound, The first liquid crystal retardation layer and the second liquid crystal retardation layer both include a hardened material layer of a second liquid crystal composition containing a polymerizable liquid crystal compound, The aforementioned first bonding layer is a hardened material layer of an active energy ray curable composition, The glass transition temperatures of the aforementioned second bonding layer and the aforementioned third bonding layer are both 25°C or lower. The optical laminate according to claim 1, wherein the first bonding layer is a hardened material layer of a radically polymerizable adhesive composition. The optical laminate according to claim 1 or 2, wherein the thickness of the protective layer, the liquid crystal polarizer, the first liquid crystal retardation layer, and the second liquid crystal retardation layer is less than 20.0 μm. The optical laminated body according to claim 1 or 2, wherein the distance from the surface of the protective layer on the opposite side to the liquid crystal polarizer side to the side of the third bonding layer on the side of the second liquid crystal retardation layer is When the distance from the opposite surface is D1 [μm], The total thickness D2 [μm] of the second bonding layer and the third bonding layer is 40% or more and 70% or less of D1. The optical laminate according to claim 1 or 2 further includes a coating layer that covers the surface of the liquid crystal polarizer on the first bonding layer side.

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