Optical film

Abstract

The present invention aims to provide an optical film that makes it easy to recognize an area where a liquid crystal layer is formed. The optical film comprises a first liquid crystal layer. The first liquid crystal layer has a first end region including one end in the width direction and a first adjacent region adjacent to the first end region in the width direction, and the first end region and the first adjacent region satisfy at least one of the following relationships [a1] and [b1]. [a1] The reflectance of the first terminal region and the reflectance of the first adjacent region are different from each other. [b1] The transmittance of the first stage region and the transmittance of the first adjacent region are different from each other.

Description

Technology Field

[0001] The present invention relates to an optical film. Background Technology

[0002] In display devices such as organic EL display devices or liquid crystal display devices, a component including an optically anisotropic film, such as a polarizing film or a phase difference film, is used. As such an optically anisotropic film, it is known that a layer of a liquid crystal compound is formed on a substrate film. For example, Patent Document 1 describes a method for manufacturing a phase difference film using a liquid crystal compound, wherein a phase difference layer is formed by applying a composition containing a liquid crystal compound onto an alignment film formed on a transparent substrate. Prior art literature

[0003] [Patent Document 1] Japanese Patent Publication No. 2014-186248 The problem to be solved

[0004] When a phase difference layer is formed by applying a composition containing a liquid crystal compound onto a substrate layer, it is difficult to apply the composition to the entire surface of the substrate layer. Consequently, the phase difference layer may not be formed on the surface of the end portion of the substrate layer, leaving the substrate layer exposed. Since the substrate layer is typically colorless and transparent, it is particularly difficult to determine the location of the end portion of the phase difference layer formed on the substrate layer when the phase difference layer is colorless and transparent. Consequently, it is difficult to recognize the area where the phase difference layer is formed, making it difficult to properly recognize the effective range for use as a phase difference film, or the range for applying an adhesive or adhesive when, for example, another layer is laminated onto the phase difference layer formed on the substrate layer through an adhesive layer.

[0005] The present invention is made in consideration of the above-mentioned points and aims to provide an optical film that makes it easy to recognize the area where a liquid crystal layer is formed. means of solving the problem

[0006] The present invention provides an optical film as described below.

[0007] [1] An optical film comprising a first liquid crystal layer,

[0008] The first liquid crystal layer has a first end region including one end in the width direction and a first adjacent region adjacent to the first end region in the width direction.

[0009] The first terminal region and the first adjacent region are an optical film satisfying at least one of the following [a1] and [b1].

[0010] [a1] The reflectance of the first terminal region and the reflectance of the first adjacent region are different from each other.

[0011] [b1] The transmittance of the first terminal region and the transmittance of the first adjacent region are different from each other.

[0012] [2] The first terminal region and the first adjacent region are optical films described in [1] that satisfy at least one of the following [a2] and [b2].

[0013] [a2] The reflectance of the first terminal area is higher than the reflectance of the first adjacent area.

[0014] [b2] The transmittance of the first terminal region is lower than the transmittance of the first adjacent region.

[0015] [3] The first terminal region and the first adjacent region are optical films described in [1] or [2], in which at least one of the values ​​of haze, brightness, reflective color, color difference, and polarization degree is different.

[0016] [4] The first end region above is an optical film described in any one of [1] to [3], comprising both ends in the width direction of the first liquid crystal layer.

[0017] [5] The first adjacent region is an optical film described in any one of [1] to [4], which is the entire region other than the first terminal region in the first liquid crystal layer.

[0018] [6] An optical film described in any one of [1] to [5] further comprising a first substrate layer.

[0019] [7] Further including an adhesive layer and a resin film,

[0020] An optical film described in any one of [1] to [5] comprising the first liquid crystal layer, the adhesive layer, and the resin film in this order.

[0021] [8] Further including an adhesive layer and a resin film,

[0022] An optical film described in [6] comprising the first substrate layer, the first liquid crystal layer, the adhesive layer, and the resin film in this order.

[0023] [9] The resin film above is an optical film described in [7] or [8] that includes a polarizing layer.

[0024]

[10] The above resin film is an optical film described in any one of [7] to [9] that includes a second liquid crystal layer.

[0025]

[11] The second liquid crystal layer has a second end region including one end in the width direction and a second adjacent region adjacent to the second end region in the width direction,

[0026] The above second terminal region and the above second adjacent region are an optical film described in

[10] that satisfies at least one of the relationships [c1] and [d1] below.

[0027] [c1] The reflectance of the second stage region and the reflectance of the second adjacent region are different from each other.

[0028] [d1] The transmittance of the second stage region and the transmittance of the second adjacent region are different from each other.

[0029]

[12] The second terminal region and the second adjacent region are optical films described in

[11] that satisfy at least one of the following [c2] and [d2] relationships.

[0030] [c2] The reflectance of the second stage area is higher than the reflectance of the second adjacent area.

[0031] [d2] The transmittance of the second stage region is lower than the transmittance of the second adjacent region.

[0032]

[13] The resin film above further comprises a second substrate layer,

[0033] The second substrate layer is an optical film described in

[11] or

[12] that is provided on the opposite side from the adhesive layer side of the second liquid crystal layer. Effects of the invention

[0034] According to the present invention, an optical film that makes it easy to recognize an area where a liquid crystal layer is formed can be provided. Brief explanation of the drawing

[0035] FIG. 1(a) is a schematic plan view schematically showing an example of an optical film of the present invention, and FIG. 1(b) is a cross-sectional view taken along the line X-X' of FIG. 1(a). FIGS. 2(a) and FIGS. 2(b) are schematic cross-sectional views schematically illustrating other examples of the optical film of the present invention. FIG. 3 is a schematic cross-sectional view schematically showing another example of the optical film of the present invention. Specific details for implementing the invention

[0036] Hereinafter, preferred embodiments of the optical film of the present invention will be described with reference to the drawings. Furthermore, each embodiment and its variations described below may be combined arbitrarily. In addition, in each embodiment and its variations, the same reference numerals are used for components identical to those described in the preceding embodiment or its variations, and their descriptions are omitted.

[0037] [Embodiment 1]

[0038] (Optical film (10))

[0039] FIG. 1(a) is a schematic plan view schematically showing an example of an optical film of the present embodiment, and FIG. 1(b) is a cross-sectional view taken along the line X-X' of FIG. 1(a). In the drawings, W represents the width direction, and L represents a direction orthogonal to the width direction (W) (hereinafter referred to as the "orthogonal direction"). The optical film (10) of the present embodiment includes a first liquid crystal layer (12) on a first substrate layer (11) as shown in FIG. 1(a) and FIG. 1(b), and the first liquid crystal layer (12) has a first end region (12a) including both ends in the width direction (W), and a first adjacent region (12b) adjacent to the first end region (12a) in the width direction (W). The first end region (12a) is provided at each end in the width direction (W) of the first liquid crystal layer (12). The first section (12a) and the first adjacent section (12b) satisfy at least one of the following [a1] and [b1] relationships.

[0040] [a1] The reflectance of the first terminal region (12a) and the reflectance of the first adjacent region (12b) are different from each other.

[0041] [b1] The transmittance of the first terminal region (12a) and the transmittance of the first adjacent region (12b) are different from each other.

[0042] The first section (12a) and the first adjacent section (12b) may satisfy at least one of the following [a2] and [b2] relationships.

[0043] [a2] The reflectance of the first terminal region (12a) is higher than the reflectance of the first adjacent region (12b).

[0044] [b2] The transmittance of the first terminal region (12a) is lower than the transmittance of the first adjacent region (12b).

[0045] The optical film (10) may be a long-length film or a single-sheet film. If the optical film (10) is a long-length film, the width direction (W) may be a direction orthogonal to the length direction of the film (a direction parallel to the orthogonal direction (L) in FIG. 1(a)). In the optical film (10), in the cross-section of the width direction, as shown in FIG. 1(b), the first liquid crystal layer (12) has a shorter length in the width direction (W) than the first substrate layer (11), and the positions of both ends in the width direction (W) of the first liquid crystal layer (12) are located inward from the positions of both ends in the width direction (W) of the first substrate layer (11). Additionally, the positions of both ends in the width direction (W) of the first substrate layer (11) and the first liquid crystal layer (12) may be the same.

[0046] The first substrate layer (11) functions as a support layer that supports the first liquid crystal layer (12) formed thereon, and can be peelable with respect to the first liquid crystal layer (12). The first substrate layer (11) is preferably a film formed by an optically transparent (colorless transparent) resin. In this specification, "optically transparent" means having a transmittance of 90% or more for light rays with a wavelength of 380 to 780 nm and a haze of 2% or less.

[0047] The first liquid crystal layer (12) is a liquid crystal cured layer formed by applying a composition for forming a liquid crystal layer, such as a polymerizable liquid crystal compound, onto the first substrate layer (11) and solidifying (curing) the liquid crystal compound. By solidifying the liquid crystal compound in an oriented state, phase difference characteristics can be imparted to the optical film (10).

[0048] The first liquid crystal layer (12) has a first end region (12a) including both ends in the width direction (W) and a first adjacent region (12b) adjacent to the first end region (12a). In FIGS. 1(a) and FIGS. 1(b), the first end region (12a) is shown as a diagonal line going down to the right. In the optical film (10) shown in FIGS. 1(a) and FIGS. 1(b), the space between the two first end regions (12a) located at both ends of the first liquid crystal layer (12) is the first adjacent region (12b), and the entire area other than the first end region (12a) is the first adjacent region (12b). The first end region (12a) of the first liquid crystal layer (12) illustrated in FIG. 1(a) is formed in a band shape with a constant width continuously in an orthogonal direction (L) perpendicular to the width direction (W) at both ends of the first liquid crystal layer (12) in the width direction (W).

[0049] When the first terminal region (12a) and the first adjacent region (12b) are observed under the same measurement conditions, it is preferable that at least one of the relationships [a1] and [b1] is satisfied, or both relationships are satisfied. The relationship of [a1] may be the relationship of [a2] or the relationship of [a3] below. Additionally, the relationship of [b1] may be the relationship of [b2] or the relationship of [b3] below.

[0050] [a3] The reflectance of the first terminal area (12a) is lower than the reflectance of the first adjacent area (12b).

[0051] [b3] The transmittance of the first terminal region (12a) is higher than the transmittance of the first adjacent region (12b).

[0052] Additionally, as shown in FIG. 1(a) and FIG. 1(b), the optical film (10) has two first end regions (12a) at both ends of the first liquid crystal layer (12), but if each of these two first end regions (12a) and the first adjacent region (12b) satisfy at least one of the relationships [a1] and [b1], the transmittance and reflectance of the two first end regions (12a) may be the same or different. The reflectance and transmittance may be measured using a known method under the same measurement conditions for the first end region (12a) and the first adjacent region (12b), and it is preferable to measure them by an inspection device during a process such as transporting the optical film (10).

[0053] There are no particular restrictions on the light source used when measuring reflectance or transmittance, but a white light source such as natural light, fluorescent lamps, or white LEDs is preferred. The illuminance of the light source is preferably 1,000 LUX or higher, and particularly preferably 2,000 LUX or higher.

[0054] The reflectance may be any one of total reflection, diffuse reflectance, or specular reflectance. The reflectance may be measured, for example, in SCE (specular reflection removal) mode or SCI (specular reflection inclusion) mode. The difference in reflectance between the first stage area (12a) and the first adjacent area (12b) may be 0.1% or more, 0.15% or more, 0.2% or more, 0.25% or more, 0.3% or more, 0.4% or more, 0.5% or more, 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, preferably 4.0% or more, more preferably 5.0% or more, and even more preferably 10% or more. If the difference in reflectance is within the above-mentioned range, it is desirable because it can be measured by an inspection device during the return process of the optical film (10).

[0055] The transmittance may be any one of total light transmittance (Tt), diffuse transmittance (Td), or linear transmittance (Tp). The difference in transmittance between the first terminal region (12a) and the first adjacent region (12b) may be 0.5%, 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, preferably 4.0% or more, more preferably 5.0% or more, and even more preferably 10% or more. It is desirable that the difference in transmittance be within the above-mentioned range, as this allows for measurement by an inspection device during the transport process of the optical film (10).

[0056] As described above, by satisfying the relationship between at least one of [a1] and [b1] for the first end region (12a) and the first adjacent region (12b) of the first liquid crystal layer (12) in the optical film (10), it becomes easier to distinguish between the first end region (12a) and the first adjacent region (12b). For example, in the optical film (10), as shown in FIG. 1(b), there may be cases where the first liquid crystal layer (12) is not formed on the first substrate layer, such as at the end of the first substrate layer (11). In such an optical film (10), for example, when the first substrate layer and the first liquid crystal layer are optically transparent, it is particularly difficult to recognize the formation range of the first liquid crystal layer provided on the first substrate layer. However, as shown in the optical film (10) illustrated in FIG. 1(a) and FIG. 1(b), the relationship between the first terminal region (12a) and the first adjacent region (12b) is such that, for example, at least one of the relationship between [a2] and [b2] is easy to determine, and thus the formation range of the first liquid crystal layer (12) on the first substrate layer (11) becomes easy to recognize.

[0057] By this, for example, when a resin film is laminated through an adhesive layer on the first liquid crystal layer (12) of an optical film (10) as described below, the area where the first liquid crystal layer (12) is formed on the first substrate layer (11) can be recognized, so the area where the adhesive layer is formed can be appropriately set. In addition, even when the area where the first liquid crystal layer (12) is formed is cut from the optical film (10) for product manufacturing, etc., the area where the first liquid crystal layer (12) is formed can be recognized, so the slicing efficiency of the area where the first liquid crystal layer (12) is formed can be improved, and the unused portion (e.g., waste portion) removed from the optical film (10) can be reduced.

[0058] The reflectance in each region of the first liquid crystal layer (12) can be changed, for example, by adjusting the haze, brightness, or reflective color of the first liquid crystal layer (12). In order to make the reflectance of the first terminal region (12a) and the reflectance of the first adjacent region (12b) different by adjusting the haze, the haze of the first terminal region (12a) and the haze of the first adjacent region (12b) may be made different from each other. Brightness or reflective color (a * or b * In order to make the reflectance of the first terminal region (12a) and the reflectance of the first adjacent region (12b) different by adjusting the light incident on the first liquid crystal layer (12), for example, the light incident on the first liquid crystal layer (12) may be made to be relatively reflective in the first terminal region (12a) (e.g., colored white) and relatively difficult to reflect in the first adjacent region (12b) (e.g., not colored and made optically transparent), or the light incident on the first liquid crystal layer (12) may be made to be relatively difficult to reflect in the first terminal region (12a) (e.g., colored black) and relatively easy to reflect in the first adjacent region (12b) (e.g., not colored and made optically transparent).

[0059] The difference in haze between the first terminal area (12a) and the first adjacent area (12b) may be 1.0% or more, 2.0% or more, 3.0% or more, 4.0% or more, preferably 5.0% or more, and more preferably 10.0% or more. The difference in brightness between the first terminal area (12a) and the first adjacent area (12b) may be 3 or more, preferably 5 or more, and more preferably 10 or more. The difference in reflective color between the first terminal area (12a) and the first adjacent area (12b) is a * Regarding , it may be 0.5 or higher, preferably 1.0 or higher, and more preferably 1.5 or higher, and b * Regarding this, it may be 0.5 or higher, more preferably 1.0 or higher, and even more preferably 1.5 or higher. When the haze, brightness, and reflective color are within the above ranges, it is suitable because the first terminal area (12a) and the first adjacent area (12b) can be simply and easily distinguished.

[0060] Additionally, the transmittance in each region of the first liquid crystal layer (12) can be changed, for example, by adjusting the haze, color difference, or polarization degree of the first liquid crystal layer (12). To make the transmittance of the first region (12a) and the transmittance of the first adjacent region (12b) different by adjusting the haze, the haze of the first region (12a) and the haze of the first adjacent region (12b) can be made different from each other. To make the transmittance of the first region (12a) and the transmittance of the first adjacent region (12b) different by adjusting the color difference, for example, the light incident on the first liquid crystal layer (12) can be made to be relatively difficult to transmit in the first region (12a) (e.g., colored) and relatively easy to transmit in the first adjacent region (12b) (e.g., optically transparent). In order to make the transmittance of the first terminal region (12a) and the transmittance of the first adjacent region (12b) different by adjusting the degree of polarization, a method of making the degree of polarization in the first terminal region (12a) and the degree of polarization in the first adjacent region different can be used, for example, making the degree of polarization in the first terminal region (12a) higher than the degree of polarization in the first adjacent region.

[0061] The difference in haze between the first terminal area (12a) and the first adjacent area (12b) may be 0.5% or more, 1.0% or more, 2.0% or more, 3.0% or more, 4.0% or more, preferably 5.0% or more, and more preferably 10.0% or more. The color difference (ΔE) between the first terminal area (12a) and the first adjacent area (12b) *ab) may be 3 or more, may be 5 or more, preferably 7 or more, and more preferably 10 or more. The difference in polarization degree between the first terminal region (12a) and the first adjacent region (12b) may be 0.01% or more, may be 0.05% or more, preferably 0.1% or more, and more preferably 0.5% or more. When the haze, color difference, or polarization degree is within the above-mentioned range, the first terminal region (12a) and the first adjacent region (12b) can be distinguished simply and easily, making it suitable.

[0062] Since the first adjacent region (12b) of the first liquid crystal layer (12) is often used as a region having optical anisotropy, it is preferable that it be optically transparent, and since the first terminal region (12a) is often removed when processed into a product, it may be colored.

[0063] The width direction (W) length of the first section region (12a) is typically 50 mm or less, preferably 35 mm or less, more preferably 20 mm or less, and even more preferably 10 mm or less. The width direction (W) lengths of the two first sections region (12a) may be the same or different from each other. Since the first section region (12a) is a part that is removed when the optical film is manufactured into a product, it is desirable to make it as narrow a range as possible. The width direction (W) length of the first adjacent section region (12b) is not particularly limited, but, for example, it can be 700 mm or more.

[0064] (Method for manufacturing optical film (10))

[0065] The optical film (10) can be manufactured by, for example, applying a composition for forming a liquid crystal layer (12) to a first substrate layer (11) and solidifying (curing) a liquid crystal compound to form a first liquid crystal layer (12). At this time, it is preferable to solidify the liquid crystal compound while it is oriented. The composition for forming a liquid crystal layer may include a liquid crystal compound or a solvent, and it is preferable that the solvent be removed by drying or the like after application to the first substrate layer (11). As for the liquid crystal compound, it is preferable to use a polymerizable liquid crystal compound having a polymerizable group, and it is preferable to polymerize and cure the polymerizable liquid crystal compound after applying the composition for forming a liquid crystal layer to the first substrate layer (11).

[0066] In order to form a first terminal region (12a) or a first adjacent region (12b) in the first liquid crystal layer (12), it is preferable to perform a treatment to form these regions when forming the first liquid crystal layer (12) by applying a composition for forming a liquid crystal layer on the first substrate layer (11).

[0067] As described above, in order to make the reflectance of the first terminal region (12a) and the reflectance of the first adjacent region (12b) different in the first liquid crystal layer (12), [i] the haze of the first terminal region (12a) and the haze of the first adjacent region (12b) may be different, and [ii] the reflection state of light incident on the first liquid crystal layer (12) may be different in the first terminal region (12a) and the first adjacent region (12b).

[0068] Methods for differentiating the haze of the first stage region (12a) and the haze of the first adjacent region (12b) include: applying a liquid crystal layer forming composition on the first substrate layer (11) to form the first liquid crystal layer (12); dropping a solvent onto the liquid crystal layer forming composition applied to the area that becomes the first stage region (12a); imparting fine irregularities to the surface of the first stage region (12a) by blast processing the surface of the first liquid crystal layer (12) that becomes the first stage region (12a); adding fine particles to the liquid crystal layer forming composition applied to the area that becomes the first stage region (12a); adding an incompatible composition to the liquid crystal layer forming composition applied to the area that becomes the first stage region (12a); and adding high refractive index fine particles.

[0069] Methods for varying the reflection state of light incident on the first liquid crystal layer (12) in the first terminal region (12a) and the first adjacent region (12b) include making the light incident on the first liquid crystal layer (12) relatively reflective or difficult to reflect in the first terminal region (12a), and relatively difficult to reflect or easy to reflect in the first adjacent region (12b). Methods for making the light incident on the first liquid crystal layer (12) relatively reflective in the first terminal region (12a) and difficult to reflect in the first adjacent region (12b) include coloring the region that becomes the first terminal region (12a) with a color (e.g., white) that makes the light incident on the first liquid crystal layer (12) relatively reflective, and not coloring (making the first adjacent region (12b) optically transparent), and depositing a metal film in the region that becomes the first terminal region (12a). A method to make light incident on the first liquid crystal layer (12) difficult to reflect in the first terminal region (12a) and easy to reflect in the first adjacent region (12b) may be described by coloring the region that becomes the first terminal region (12a) with a color (e.g., black) that makes light incident on the first liquid crystal layer (12) relatively difficult to reflect, and not coloring the first adjacent region (12b) (making it optically transparent). Coloring in the first terminal region (12a) of the first liquid crystal layer (12) can be performed, for example, by applying or adding a pigment or dye to a liquid crystal layer forming composition applied to the region that becomes the first terminal region (12a) using an inkjet coating device or the like.

[0070] In addition, as described above, in order to make the transmittance of the first terminal region (12a) and the transmittance of the first adjacent region (12b) different in the first liquid crystal layer (12), [i] the haze of the first terminal region (12a) and the haze of the first adjacent region (12b) are different, [ii] the ease of light transmission incident on the first liquid crystal layer (12) is different in the first terminal region (12a) and the first adjacent region (12b), and [iii] the degree of polarization in the first terminal region (12a) and the degree of polarization in the first adjacent region are different.

[0071] A method for making the haze of the first section area (12a) and the haze of the first adjacent area (12b) different can be the method described above.

[0072] As a method of varying the ease of light transmission incident on the first liquid crystal layer (12) in the first terminal region (12a) and the first adjacent region (12b), for example, a method in which light incident on the first liquid crystal layer (12) is relatively difficult to transmit in the first terminal region (12a) and relatively easy to transmit in the first adjacent region (12b) may be cited. As such a method, the first terminal region (12a) may be colored with a color (e.g., white or black) through which light incident on the first liquid crystal layer (12) is relatively difficult to transmit, and the first adjacent region (12b) may not be colored (made optically transparent). Coloring in the first terminal region (12a) of the first liquid crystal layer (12) may be performed, for example, using an inkjet coating device as described above.

[0073] Methods for differentiating the degree of polarization in the first terminal region (12a) and the degree of polarization in the first adjacent region include different amounts of dichromatic pigment added to impart the degree of polarization in the first terminal region (12a) and the first adjacent region (12b), and different orientations of the dichromatic pigment in the first terminal region (12a) and the first adjacent region (12b). For example, methods include adding a dichromatic pigment to the first terminal region (12a) to orient it and impart a degree of polarization, and not adding a dichromatic pigment to the first adjacent region (12b) and not imparting a degree of polarization, and increasing the degree of orientation of the dichromatic pigment in the first terminal region (12a) to relatively increase the degree of polarization, and decreasing the degree of orientation of the dichromatic pigment in the first adjacent region to relatively decrease the degree of polarization.

[0074] Methods for adding a dichromatic pigment to the first stage region (12a) include, for example, using an inkjet coating device as described above, or adding a dichromatic pigment to a liquid crystal layer forming composition for forming the first liquid crystal layer (12). When using a liquid crystal forming composition containing a dichromatic pigment, it is preferable to apply the liquid crystal layer forming composition containing the dichromatic pigment to the region that increases polarization degree, or to apply the liquid crystal layer forming composition containing the dichromatic pigment at a higher concentration.

[0075] Additionally, as a method to increase the degree of orientation of the dichromatic pigment in the first stage region (12a), an orientation layer is provided between the first substrate layer (11) and the first liquid crystal layer (12), and the degree of orientation of the liquid crystal compound in the first stage region (12a) is increased by adjusting the orientation regulating force of the orientation layer. When a polymerizable liquid crystal compound is used as the liquid crystal compound, a method to increase the degree of orientation of the liquid crystal compound in the first stage region (12a) is provided by using a mask, etc., to perform polarized light irradiation on the first stage region (12a) and not to perform polarized light irradiation on the first adjacent region. In this case, it is preferable to add the dichromatic pigment to the composition for forming the liquid crystal layer applied on the first substrate layer (11). In addition, when using a liquid crystal compound in which the dichromatic pigment itself has liquid crystal properties or the dichromatic pigment itself has polymerizable functional groups, examples include the method of adjusting the degree of orientation by adjusting the shear stress during coating, as described in Japanese Patent Publication No. 2002-180052, and the method of adjusting the degree of orientation by adjusting the magnetic field or electric field.

[0076] (A variation of Embodiment 1)

[0077] Variations of the present embodiment will be described below, but the above-described embodiment and each of the following variations may be combined arbitrarily.

[0078] (Variation Example 1)

[0079] In the optical film (10) illustrated in FIG. 1(a) and FIG. 1(b), the case in which a first terminal region (12a) is formed at each end of the width direction (W) of the first liquid crystal layer (12) has been described as an example, but the first terminal region may be formed at either end of the width direction (W) of the first liquid crystal layer. In this case, the end of the width direction (W) of the first liquid crystal layer where the first terminal region is not formed may be a first adjacent region.

[0080] (Variation Example 2)

[0081] In the optical film (10) illustrated in FIG. 1(a) and FIG. 1(b), the case where the entire area other than the first terminal region (12a) of the first liquid crystal layer (12) is the first adjacent region has been described as an example, but this is not limited to cases where the first terminal region and the first adjacent region are adjacent in the width direction (W). For example, only the part adjacent to the first terminal region may be designated as the first adjacent region, and the area opposite to the first terminal region of the first adjacent region may be designated as the area other than these.

[0082] (Variation Example 3)

[0083] The optical film (10) illustrated in FIG. 1(a) and FIG. 1(b) has a first substrate layer (11), but may not have the first substrate layer (11). An optical film that does not have the first substrate layer can be obtained, for example, by peeling off the first substrate layer (11) from the optical film (10).

[0084] (Variation Example 4)

[0085] In the optical film (10) illustrated in FIG. 1(a) and FIG. 1(b), the first end region (12a) is described as being formed in a strip shape with a constant width in the orthogonal direction (L) which is orthogonal to the width direction (W), but this is not limited thereto. For example, the width of the first end region (12a) may not be constant in the orthogonal direction (L) and may vary. When the first end region (12a) is formed at each end of the width direction (W) of the first liquid crystal layer (12), the width of one first end region may be constant and the width of the other first end region may vary, or the widths of both first end regions may vary, and these variations may be the same or different.

[0086] (Variation Example 5)

[0087] In the optical film (10) illustrated in FIG. 1(a) and FIG. 1(b), the case in which the first end region (12a) is formed continuously in an orthogonal direction has been described as an example, but the first end region may be formed intermittently in an orthogonal direction (L). When the first end region is formed intermittently, it is preferable to form it with a gap such that the end of the first liquid crystal layer can be recognized.

[0088] (Variation Example 6)

[0089] The optical film (10) illustrated in FIG. 1(a) and FIG. 1(b) has been described as having a first liquid crystal layer (12) on a first substrate layer (11) as an example, but may also have a first alignment layer between the first substrate layer and the first liquid crystal layer. Additionally, the optical film may not have a first substrate layer, but may have a first liquid crystal layer and a first alignment layer. An optical film having a first alignment layer and not having a first substrate layer can be obtained, for example, by peeling off the first substrate layer from a laminate having a first substrate layer, a first alignment layer, and a first liquid crystal layer in this order. In this case, when peeling off the first substrate layer, it is preferable to adjust the adhesion force between each layer so that the first alignment layer remains on the first liquid crystal layer. Additionally, an optical film having neither a first substrate layer nor a first alignment layer can be obtained, for example, by peeling off the first substrate layer and the first alignment layer from the laminate. In this case, when peeling off the first substrate layer, it is preferable to adjust the adhesion between each layer so that the first orientation layer can be peeled off together with the first substrate layer. The adhesion between each layer can be adjusted by the components included in each layer or by surface treatment performed on the surface of each layer.

[0090] [Embodiment 2]

[0091] The optical film of this embodiment differs from Embodiment 1 in that it has an adhesive layer and a resin film on the opposite side from the first substrate layer of the first liquid crystal layer. Hereinafter, the same reference numerals are used for components identical to those described in the previous embodiment, and their descriptions are omitted.

[0092] (Optical film(50, 51))

[0093] FIGS. 2(a) and FIGS. 2(b) are schematic cross-sectional views illustrating an example of an optical film according to the present embodiment. In the drawings, W indicates the width direction. The optical film (50) according to the present embodiment has a first substrate layer (11), a first liquid crystal layer (12), an adhesive layer (30), and a resin film (20) in this order, as shown in FIG. 2(a). Additionally, the optical film (51) has a first substrate layer (11), a first liquid crystal layer (12), an adhesive layer (31), and a resin film (20) in this order, as shown in FIG. 2(b), and the length of the adhesive layer (31) in the width direction (W) is different from that of the optical film (50). The optical films (50, 51) may be long-length films or single-wafer films.

[0094] In the optical film (50) illustrated in FIG. 2(a), the adhesive layer (30) has a shorter width direction (W) length than the first liquid crystal layer (12) and the resin film (20) in its width direction cross-section, and the positions of both ends of the adhesive layer (30) in the width direction (W) are located inward from the positions of both ends of the first liquid crystal layer (12) and the resin film (20) in the width direction (W). The first liquid crystal layer (12) and the resin film (20) may have the same width direction (W) length or different width direction (W) lengths. Additionally, the positions of both ends of the adhesive layer (30), the first liquid crystal layer (12), and the resin film (20) in the width direction (W) may be the same. However, in order to make it difficult for the transport path to be contaminated by the adhesive layer (30) when transporting the optical film (50), it is preferable that the positions of both ends in the width direction (W) of the resin film (20) be the same as or further out than the positions of both ends in the width direction (W) of the adhesive layer (30). Additionally, the positions of both ends in the width direction (W) of the adhesive layer (30) may be the same as the positions of both ends in the width direction (W) of one of the first liquid crystal layer (12) and the resin film (20), and may be further inward than the positions of both ends in the width direction (W) of the other.

[0095] Meanwhile, in the optical film (51) illustrated in FIG. 2(b), in the cross-section in the width direction, the width direction (W) of the adhesive layer (31) is longer than the width direction (W) of the first liquid crystal layer (12) and shorter than the width direction (W) of the resin film (20), and the positions of both ends in the width direction (W) of the adhesive layer (31) are located further outward than the positions of both ends in the width direction (W) of the first liquid crystal layer (12) and further inward than the positions of both ends in the width direction (W) of the resin film (20). The adhesive layer (31) and the resin film (20) may have the same position at both ends in the width direction (W), but in order to prevent the conveying path from being contaminated by the adhesive layer (31) when conveying the optical film (51), it is preferable that the positions at both ends in the width direction (W) of the first substrate layer (11) and the resin film (20) be the same as or further outward from the positions at both ends in the width direction (W) of the adhesive layer (31). The first substrate layer (11) and the resin film (20) may have the same length in the width direction (W) or different lengths.

[0096] The first substrate layer (11) and the first liquid crystal layer (12) are as described in the previous embodiment. The adhesive layer (30) and the adhesive layer (31) are layers for bonding the first liquid crystal layer (12) and the resin film (20), and the adhesive layer (31) of the optical film (51) shown in FIG. 2(b) also directly bonds the first substrate layer (11) and the resin film (20) at both ends in the width direction (W). It is preferable that the adhesive layer (30) and the adhesive layer (31) are optically transparent. The resin film (20) can be, for example, an optical functional film such as a polarizing plate or a reflective film including a polarizing layer, or a separator that protects the adhesive layer (30, 31). If the resin film (20) is a separator, the lengths in the width direction (W) of the adhesive layer (30, 31) and the resin film (20) may be the same. If the resin film (20) is an optically functional film, it is desirable that it be optically transparent.

[0097] The first liquid crystal layer (12) of the optical film (50, 51) has a first terminal region (12a) and a first adjacent region (12b) as described in the previous embodiment, and when these two regions are observed under the same measurement conditions, they satisfy at least one of the relationships [a1] and [b1] described above. Therefore, in the optical film (50, 51), it becomes easy to distinguish the first terminal region (12a) and the first adjacent region (12b) of the first liquid crystal layer (12). For example, since it is easy to distinguish the first terminal region (12a) in the optical film (10) by having at least one of the relationships [a2] and [b2], it becomes easy to recognize the formation range of the first liquid crystal layer (12) in the optical film (50, 51). By this, when cutting out an area where the first liquid crystal layer (12) is formed from an optical film (50, 51) for product manufacturing, etc., the area where the first liquid crystal layer (12) is formed can be recognized, thereby improving the slicing efficiency of the area where the first liquid crystal layer (12) is formed, and reducing the unused portion (e.g., waste portion) that is removed from the optical film (50, 51).

[0098] Additionally, the optical film (50, 51) may be used by peeling off the first substrate layer (11). In this case, in the optical film (50) shown in FIG. 2(a), the positions of both ends in the width direction (W) of the adhesive layer (30) are located inward compared to the positions of both ends in the width direction (W) of the first liquid crystal layer (12), and since the first substrate layer (11) and the resin film (20) are not directly bonded through the adhesive layer (30), the first substrate layer (11) can be appropriately peeled off. Regarding this, in the optical film (51) illustrated in FIG. 2(b), the positions of both ends in the width direction (W) of the adhesive layer (31) are located further outward than the positions of both ends in the width direction (W) of the first liquid crystal layer (12), and since the first substrate layer (11) and the resin film (20) are directly bonded through the adhesive layer (31), it is difficult to properly peel off the first substrate layer (11), and if one attempts to peel off the first substrate layer (11) from the optical film (51), the first substrate layer (11) may break during peeling. Therefore, in the optical film (51), it is preferable to peel off the first substrate layer (11) after removing the area where the first substrate layer (11) and the resin film (20) are directly bonded by slitting, etc.

[0099] As described above, in the optical film (50, 51), for example, by making it easy to recognize the first end region (12a) of the first liquid crystal layer (12), while checking the first end region (12a) of the first liquid crystal layer (12), it is possible to check whether the first substrate layer (11) and the resin film (20) are directly bonded through the adhesive layer (30, 31) at both ends in the width direction (W) of the optical film (50, 51), which are outside the end portion in the width direction (W) of the first liquid crystal layer (12). By doing so, in the optical film (51) shown in FIG. 2(b), it can be determined that the first substrate layer (11) needs to be peeled off after removing both ends in the width direction (W) of the optical film (51), and thus, when peeling the first substrate layer (11) from the optical film, the first substrate layer (11) can be suppressed from breaking. In addition, in the optical film (50) shown in FIG. 2(a), since it can be determined that there is no need to slit both ends, the process of peeling off the first substrate layer (11) from the optical film can be simplified.

[0100] (Method for manufacturing optical film (50, 51))

[0101] The optical film (50, 51) can be manufactured, for example, using the optical film (10) illustrated in FIG. 1(a) and FIG. 1(b). In this case, the first liquid crystal layer (12) side of the optical film (10) and the resin film (20) are laminated through an adhesive composition layer for forming an adhesive layer (30, 31), and then, if necessary, the adhesive composition layer is cured to form the adhesive layer (30, 31), thereby obtaining the optical film (50, 51). The adhesive composition layer may be provided on the first liquid crystal layer (12) of the optical film (10), may be provided on the resin film (20), or may be provided on both of these.

[0102] In the optical film (10), the first end region (12a) and the first adjacent region (12b) of the first liquid crystal layer (12) can be identified because at least one of the reflectance and transmittance is different. This makes it easier to appropriately set the range of the adhesive composition layer for forming the adhesive layer (30, 31). Therefore, it is easy to manufacture an optical film (50) in which the positions of both ends in the width direction (W) of the adhesive layer (30) are located inward compared to the positions of both ends in the width direction (W) of the first liquid crystal layer (12), or to manufacture an optical film (51) in which the positions of both ends in the width direction (W) of the adhesive layer (31) are located outward compared to the positions of both ends in the width direction (W) of the first liquid crystal layer (12).

[0103] (A variation of Embodiment 2)

[0104] Variations of the present embodiment will be described below, but the above-described embodiment and each of the following variations may be combined arbitrarily.

[0105] (Variation Example 1)

[0106] The optical film (50, 51) illustrated in FIG. 2(a) and FIG. 2(b) has a first substrate layer (11), but may not have the first substrate layer (11). An optical film that does not have the first substrate layer (11) can be obtained, for example, by peeling off the first substrate layer (11) from the optical film (50, 51) as described above, and has a first liquid crystal layer, an adhesive layer, and a resin film in this order.

[0107] (Variation Example 2)

[0108] In the optical film (50, 51) illustrated in FIG. 2(a) and FIG. 2(b), although the case having a first substrate layer (11), a first liquid crystal layer (12), an adhesive layer (30), and a resin film (20) has been described as an example, a first alignment layer may be formed between the first substrate layer and the first liquid crystal layer. Additionally, the optical film may not have a first substrate layer, but may have a first alignment layer, a first liquid crystal layer, an adhesive layer, and a resin film in this order. Such an optical film can be obtained, for example, by peeling off the first substrate layer from a laminate having a first substrate layer, a first alignment layer, a first liquid crystal layer, an adhesive layer, and a resin film in this order. In this case, when peeling off the first substrate layer, it is preferable to adjust the adhesion force between each layer so that the first alignment layer remains on the first liquid crystal layer. In addition, an optical film having a first liquid crystal layer, an adhesive layer, and a resin film in this order may also be obtained, for example, by peeling off a first substrate layer and a first alignment layer from the laminate described above. In this case, when peeling off the first substrate layer, it is preferable to adjust the adhesion force between each layer so that the first alignment layer can be peeled off together with the first substrate layer. The adhesion force between each layer can be adjusted by the components included in each layer or by surface treatment performed on the surface of each layer.

[0109] (Variation Example 3)

[0110] In the optical films (50, 51) illustrated in FIG. 2(a) and FIG. 2(b), the case in which the positions of both ends in the width direction (W) of the adhesive layer (30) are inwardly or outwardly compared to the positions of both ends in the width direction (W) of the first liquid crystal layer (12) has been described as an example, but the position of one end in the width direction (W) of the adhesive layer (30) may be inwardly or outwardly compared to the position of one end in the width direction (W) of the first liquid crystal layer (12).

[0111] [Embodiment 3]

[0112] The optical film of the present embodiment differs from embodiment 2 in that it uses a film comprising a second substrate layer and a second liquid crystal layer as a resin film. Hereinafter, the same reference numerals are used for components identical to those described in the previous embodiment, and their descriptions are omitted.

[0113] (Optical film (60))

[0114] FIG. 3 is a schematic cross-sectional view schematically illustrating an example of an optical film of the present embodiment. In the drawing, W indicates the width direction. The optical film (60) of the present embodiment has, as shown in FIG. 3, a first substrate layer (11), a first liquid crystal layer (12), an adhesive layer (32), a second liquid crystal layer (22), and a second substrate layer (21) in this order. The second substrate layer (21) and the second liquid crystal layer (22) form a resin film, and in the optical film (60), the second substrate layer (21) is provided on the opposite side from the adhesive layer (32) of the second liquid crystal layer (22). The second liquid crystal layer (22) has a second end region (22a) including both ends in the width direction (W), and a second adjacent region (22b) adjacent to the second end region (22a) in the width direction (W). The second terminal region (22a) is provided at each end of the width direction (W) of the second liquid crystal layer (22). The second terminal region (22a) and the second adjacent region (22b) satisfy at least one of the following relationships [c1] and [d1].

[0115] [c1] The reflectance of the second terminal area (22a) and the reflectance of the second adjacent area (22b) are different from each other.

[0116] [d1] The transmittance of the second terminal region (22a) and the transmittance of the second adjacent region (22b) are different from each other.

[0117] The second section (22a) and the second adjacent section (22b) may satisfy at least one of the following [c2] and [d2] relationships.

[0118] [c2] The reflectance of the second terminal area (22a) is higher than the reflectance of the second adjacent area (22b).

[0119] [d2] The transmittance of the second terminal region (22a) is lower than the transmittance of the second adjacent region (22b).

[0120] The optical film (60) may be a long-length film or a single-sheet film. In the optical film (60) illustrated in FIG. 3, in the cross-section in the width direction, the second liquid crystal layer (22) has a shorter length in the width direction (W) than the second substrate layer (21), and the positions of both ends in the width direction (W) of the second liquid crystal layer (22) are located further inward than the positions of both ends in the width direction (W) of the second substrate layer (21). Additionally, the positions of both ends in the width direction (W) of the second substrate layer (21) and the second liquid crystal layer may be the same. In addition, in the optical film (60), the adhesive layer (32) has a shorter width direction (W) length than the first liquid crystal layer (12) and the second liquid crystal layer (22) in the cross-section in the width direction, and the positions of both ends of the adhesive layer (32) in the width direction (W) are located inward compared to the positions of both ends of the first liquid crystal layer (12) and the second liquid crystal layer (22) in the width direction (W). The first liquid crystal layer (12) and the second liquid crystal layer (22) may have the same width direction (W) lengths or different width direction (W) lengths. In addition, the positions of both ends of the adhesive layer (32) in the width direction (W) may be the same as the positions of both ends of the first liquid crystal layer (12) and the second liquid crystal layer (22) in the width direction (W), or they may be located outward compared to them. However, in order to make it difficult for the transport path to be contaminated by the adhesive layer (32) when transporting the optical film (60), it is preferable that the positions of both ends in the width direction (W) of the first substrate layer (11) and the second substrate layer (21) be the same as or further out than the positions of both ends in the width direction (W) of the adhesive layer (32).

[0121] The first substrate layer (11) and the first liquid crystal layer (12) are as described in the previous embodiment. The adhesive layer (32) is a layer for bonding the first liquid crystal layer (12) and the second liquid crystal layer (22). The adhesive layer (32) is preferably optically transparent. The second substrate layer (21) functions as a support layer that supports the second liquid crystal layer (22) formed thereon, and can be peelable from the second liquid crystal layer (22). The second substrate layer (21) is preferably a film formed by an optically transparent resin. The second liquid crystal layer (22) is a layer formed by applying a composition for forming a liquid crystal layer, such as a polymerizable liquid crystal compound, onto the second substrate layer (21), and solidifying (curing) the liquid crystal compound. By curing the liquid crystal compound in an oriented state, phase difference characteristics can be imparted to the optical film (60).

[0122] The second liquid crystal layer (22) has a second end region (22a) including both ends in the width direction (W) and a second adjacent region (22b) adjacent to the second end region (22a). In FIG. 3, the second end region (22a) is shown as a diagonal line going upward to the right. In the optical film (60) shown in FIG. 3, the space between the two second end regions (22a) located at both ends of the second liquid crystal layer (22) is the second adjacent region (22b), and the entire area excluding the second end region (22a) is the second adjacent region (22b). The second end region (22a) of the second liquid crystal layer (22) shown in FIG. 3 is formed in a band shape with a constant width continuously in an orthogonal direction perpendicular to the width direction (W) at both ends of the second liquid crystal layer (22) in the width direction (W).

[0123] When the second terminal region (22a) and the second adjacent region (22b) are observed under the same measurement conditions, it is preferable that at least one of the relationships [c1] and [d1] is satisfied, and it is also preferable that both relationships are satisfied. The relationship of [c1] may be the relationship of [c2] or the relationship of [c3] below. Additionally, the relationship of [d1] may be the relationship of [d2] or the relationship of [d3] below.

[0124] [c3] The reflectance of the second terminal area (22a) is lower than the reflectance of the second adjacent area (22b).

[0125] [d3] The transmittance of the second terminal region (22a) is higher than the transmittance of the second adjacent region (22b).

[0126] Additionally, the optical film (60) has two second terminal regions (22a) at both ends of the second liquid crystal layer (22) as shown in FIG. 3, but if each of these two second terminal regions (22a) and the second adjacent region (22b) satisfy at least one of the relationships [c1] and [d1], the transmittance and reflectance of the two second terminal regions (22a) may be the same or different from each other. The reflectance and transmittance may be measured using the method described in the previous embodiment. Also, the method for adjusting the reflectance or transmittance in each region of the second liquid crystal layer (22) may use the method described in the previous embodiment.

[0127] In the optical film (60), the first liquid crystal layer (12) has a first terminal region (12a) and a first adjacent region (12b) as described in the previous embodiment, and the second liquid crystal layer (22) has a second terminal region (22a) and a second adjacent region (22b), and these regions satisfy at least one of the above-mentioned [a1] and [b1] and at least one of [c1] and [d1]. Therefore, in the optical film (60), it becomes easy to distinguish the first terminal region (12a) and the first adjacent region (12b), and also easy to distinguish the second terminal region (22a) and the second adjacent region (22b). By this, when an adhesive layer is provided on the first liquid crystal layer (12) or the second liquid crystal layer (22), the area where the first liquid crystal layer (12) or the second liquid crystal layer is formed can be recognized, so the area where the adhesive layer is formed can be appropriately set. In addition, even when the area where the first liquid crystal layer (12) and the second liquid crystal layer (22) are formed is cut from the optical film (60) for product manufacturing, etc., the area where the first liquid crystal layer (12) and the second liquid crystal layer (22) are formed can be recognized, so the slicing efficiency of the area where the first liquid crystal layer (12) and the second liquid crystal layer (22) are formed can be improved, and the unused portion (e.g., waste portion) removed from the optical film (60) can be reduced.

[0128] Additionally, the optical film (60) may be used by peeling off the first substrate layer (11) and the second substrate layer (21). In this case, if the first substrate layer (11) and the second substrate layer (21) are directly bonded through the adhesive layer (32), it becomes difficult to peel off the first substrate layer (11) or the second substrate layer (21) well, as explained in the previous embodiment regarding the case of peeling off the first substrate layer (11). In the optical film (60), for example, by making it easy to recognize the first end region (12a) of the first liquid crystal layer (12) and the second end region (22a) of the second liquid crystal layer (22), while checking these first end region (12a) and second end region (22a), it is possible to check whether the first substrate layer (11) and the second substrate layer (21) are directly bonded through the adhesive layer (32) at both ends in the width direction (W) of the optical film (60), which are outside the ends in the width direction (W) of the first liquid crystal layer (12) and the second liquid crystal layer (22). By doing so, when peeling off the first substrate layer (11) or the second substrate layer (21) from the optical film (60), it is possible to determine whether it is necessary to remove both ends in the width direction (W) depending on the formation position of the adhesive layer (32) of the optical film (60). Therefore, when peeling off the first substrate layer (11) or the second substrate layer (21), the first substrate layer (11) or the second substrate layer (21) can be suppressed from breaking, and additionally, since a process for slitting both ends of the optical film can be provided as needed, the manufacturing process can be made more efficient.

[0129] Since the second adjacent region (22b) of the second liquid crystal layer (22) is often used as a region having optical anisotropy, it is preferable that it be optically transparent, and since the second terminal region (22a) is often removed when processed into a product, it may be colored.

[0130] The width direction (W) length of the second section region (22a) is typically 50 mm or less, preferably 35 mm or less, more preferably 20 mm or less, and even more preferably 10 mm or less. The width direction (W) lengths of the two second section regions (22a) may be the same or different from each other. Since the second section region (22a) is a part that is removed when the optical film is manufactured into a product, it is desirable to make it as narrow a range as possible. The width direction (W) length of the second adjacent region (22b) is not particularly limited, but, for example, can be 700 mm or more.

[0131] In the optical film (60), the first end region (12a) of the first liquid crystal layer (12) and the second end region (22a) of the second liquid crystal layer (22) may have the same reflectance or transmittance and may have different reflectance or transmittance, and the first adjacent region (12b) and the second adjacent region (22b) may have the same reflectance or transmittance and may have different reflectance or transmittance. Additionally, in the optical film (60), the first end region (12a) of the first liquid crystal layer (12) and the second end region (22a) of the second liquid crystal layer (22) may have the same length in the width direction (W) and may have different lengths, and the first adjacent region (12b) and the second adjacent region (22b) may have the same length in the width direction (W) and may have different lengths.

[0132] (Method for manufacturing optical film (60))

[0133] The optical film (60) can be manufactured using, for example, the optical film (10) shown in FIG. 1(a) and FIG. 1(b) and a film having a second liquid crystal layer (22) formed on a second substrate layer (21) (hereinafter referred to as the "second liquid crystal layer film"). In this case, the optical film (60) can be obtained by laminating the first liquid crystal layer (12) side of the optical film (10) and the second liquid crystal layer (22) side of the second liquid crystal layer film through an adhesive composition layer for forming an adhesive layer (32), and then forming the adhesive layer (32) by curing the adhesive composition layer as needed. The adhesive composition layer may be provided on the first liquid crystal layer (12) of the optical film (10), on the second liquid crystal layer (22) of the second liquid crystal layer film, or on both of these.

[0134] In the optical film (60), the first end region (12a) and the first adjacent region (12b) of the first liquid crystal layer (12) can be distinguished because their reflectance or transmittance is different. Similarly, the second end region (22a) and the second adjacent region (22b) of the second liquid crystal layer (22) can be distinguished because their reflectance or transmittance is different. Therefore, it is easy to form an adhesive composition layer for forming an adhesive layer (32) at a desired location.

[0135] (A variation of Embodiment 3)

[0136] Variations of the present embodiment will be described below, but the above-described embodiment and each of the following variations may be combined arbitrarily.

[0137] (Variation Example 1)

[0138] In the optical film (60) illustrated in FIG. 3, the second liquid crystal layer (22) has a second terminal region (22a) and a second adjacent region (22b) as an example, but the second liquid crystal layer (22) does not have to have a second terminal region (22a) and a second adjacent region (22b).

[0139] (Variation Example 2)

[0140] In the optical film (60) illustrated in FIG. 3, the case in which a second terminal region (22a) is formed at each end of the width direction (W) of the second liquid crystal layer (22) has been described as an example, but the second terminal region may be formed at either end of the width direction (W) of the second liquid crystal layer. In this case, the end of the width direction (W) of the second liquid crystal layer where the second terminal region is not formed may be a second adjacent region.

[0141] (Variation Example 3)

[0142] In the optical film (60) illustrated in FIG. 3, the case where the entire area other than the second terminal region (22a) of the second liquid crystal layer (22) is the second adjacent region has been described as an example, but this is not limited to cases where the second terminal region and the second adjacent region are adjacent in the width direction (W). For example, only the part adjacent to the second terminal region may be designated as the second adjacent region, and the area opposite to the second terminal region of the second adjacent region may be designated as the area other than these.

[0143] (Variation Example 4)

[0144] In the optical film (60) illustrated in FIG. 3, a first substrate layer (11) and a second substrate layer (21) are present, but it may not have one or both of these. An optical film that does not have the first substrate layer (11) or the second substrate layer (21) can be obtained, for example, by peeling off the first substrate layer (11) or the second substrate layer (21) from the optical film (60) as described above.

[0145] (Variation Example 5)

[0146] In the optical film (60) illustrated in FIG. 3, the second end region (22a) is described as being formed in a strip shape with a constant width in an orthogonal direction perpendicular to the width direction (W), but this is not limited thereto. For example, the width of the second end region (22a) may not be constant in the orthogonal direction and may vary. When the second end region (22a) is formed at each end of the width direction (W) of the second liquid crystal layer (22), the width of one second end region may be constant and the width of the other second end region may vary, or the widths of both second end regions may vary, and these variations may be the same or different.

[0147] (Variation Example 6)

[0148] In the optical film (60) illustrated in FIG. 3, the case where the second terminal region (22a) is formed continuously in an orthogonal direction has been described as an example, but the second terminal region may be formed intermittently in an orthogonal direction (L). When the second terminal region is formed intermittently, it is preferable to form it with enough spacing so that the end of the second liquid crystal layer can be recognized.

[0149] (Variation Example 7)

[0150] In the optical film (60) illustrated in FIG. 3, the case in which a second liquid crystal layer (22) is formed on a second substrate layer (21) has been described as an example, but a second alignment layer may be formed between the second substrate layer and the second liquid crystal layer. Additionally, the optical film may not have a second substrate layer and may have a second liquid crystal layer on the opposite side of the adhesive layer of the second liquid crystal layer. An optical film having a second alignment layer and not having a second substrate layer can be obtained, for example, by peeling off the second substrate layer from a laminate having a first substrate layer, a first alignment layer, a first liquid crystal layer, an adhesive layer, a second liquid crystal layer, a second alignment layer, and a second substrate layer in this order, and when peeling off the second substrate layer, it is preferable to adjust the adhesion force between each layer so that the second alignment layer remains on the second liquid crystal layer. In addition, an optical film that does not have a second substrate layer or a second orientation layer may be obtained, for example, by peeling off the second substrate layer and the second orientation layer from the laminate described above, and it is preferable to adjust the adhesion between each layer so that the second orientation layer can be peeled off together with the second substrate layer when peeling off the second substrate layer. The adhesion between each layer can be adjusted by the components included in each layer or by surface treatment performed on the surface of each layer.

[0151] (Variation Example 8)

[0152] In the optical film (60) illustrated in FIG. 3, the case in which the resin film has a second substrate layer and a second liquid crystal layer has been described as an example, but it is not limited thereto. For example, the second substrate layer is peeled off, and an optical functional film such as a polarizing layer is provided through another adhesive layer on the opposite side from the adhesive layer of the second liquid crystal layer, that is, having the second liquid crystal layer, another adhesive layer, and the optical functional film in this order may be used as the resin film, and the optical film may have the first substrate layer, the first alignment layer, the first liquid crystal layer, the adhesive layer, the second liquid crystal layer, another adhesive layer, and the optical functional film in this order.

[0153] Although embodiments and variations of the present invention have been described above, the present invention is not limited to these embodiments and variations, and, for example, may be implemented by combining the structures of each of the above-described embodiments and variations. Below, each common aspect of all embodiments and variations will be described in detail.

[0154] (Optical film)

[0155] An optical film can be used as a circular polarizer by making the first liquid crystal layer and the second liquid crystal layer into phase difference layers, such as a half-wave plate, a quarter-wave plate, a quarter-wave plate with inverse wavelength dispersion, or a positive C-plate, and by using a linear polarizer as a resin film or a part of the resin film. For example, if the optical film has a first liquid crystal layer, an adhesive layer, and a resin film in this order, and the resin film is a linear polarizer, a circular polarizer can be formed by making the first liquid crystal layer a quarter-wave plate. In addition, if the optical film has a first liquid crystal layer, an adhesive layer, and a resin film in this order, and the resin film has a second liquid crystal layer, another adhesive layer, and a linear polarizer in this order starting from the adhesive layer side, the first liquid crystal layer is made a quarter-wave plate and the second liquid crystal layer is made a half-wave plate; or the first liquid crystal layer is made a positive C-plate and the second liquid crystal layer is made a quarter-wave plate with inverse wavelength dispersion. A circularly polarized plate can be formed by making the first liquid crystal layer a quarter-wave plate with inverse wavelength dispersion and the second liquid crystal layer a positive C plate, etc.

[0156] (First substrate layer and second substrate layer)

[0157] The first substrate layer and the second substrate layer (hereinafter, both may be collectively referred to as the "substrate layer") are preferably films formed from a resin material. As the resin material, for example, a resin material having excellent transparency, mechanical strength, thermal stability, and elongation properties is used. Specifically, polyolefin resins such as polyethylene and polypropylene; cyclic polyolefin resins such as norbornene-based polymers; polyester resins such as polyethylene terephthalate and polyethylene naphthalate; (meth)acrylic acid resins such as (meth)acrylic acid and poly(meth)acrylate methyl; cellulose ester resins such as triacetylcellulose, diacetylcellulose, and cellulose acetate propionate; vinyl alcohol resins such as polyvinyl alcohol and polyvinyl acetate; polycarbonate resins; polystyrene resins; polyarylate resins; polysulfone resins; polyethersulfone resins; polyamide resins; and polyimide resins. Examples include polyetherketone resins; polyphenylene sulfide resins; polyphenylene oxide resins; and mixtures and copolymers thereof. Among these resins, it is preferable to use any one of cyclic polyolefin resins, polyester resins, cellulose ester resins, and (meth)acrylic acid resins, or a mixture thereof. Furthermore, the term "(meth)acrylic acid" means "at least one of acrylic acid and methacrylic acid."

[0158] The substrate layer may be a single layer composed of one type of resin or a mixture of two or more types, or it may have a multilayer structure of two or more layers. In the case of a multilayer structure, the resins forming each layer may be the same or different. If the substrate layer is a film formed from a resin material, any additive may be added to the substrate layer. Examples of additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, release agents, anti-coloring agents, flame retardants, nucleating agents, antistatic agents, pigments, and colorants.

[0159] The thickness of the substrate layer is not particularly limited, but generally, it is preferable to have a thickness of 1 to 300 μm for workability such as strength or handling, more preferable to have a thickness of 10 to 200 μm, and even more preferable to have a thickness of 30 to 120 μm.

[0160] (1st orientation layer and 2nd orientation layer)

[0161] A first alignment layer and a second alignment layer (hereinafter collectively referred to as an "alignment layer"), which may include an optical film, have an alignment regulating power that aligns a liquid crystal compound, such as a polymerizable liquid crystal compound, included in a liquid crystal layer (first liquid crystal layer or second liquid crystal layer) formed thereon in a desired direction. Examples of alignment layers include an alignment polymer layer formed of an alignment polymer, a photoalignment polymer layer formed of a photoalignment polymer, and a groove alignment layer having an uneven pattern or a plurality of grooves on the surface of the layer. The thickness of the alignment layer is typically 10 to 5000 nm, and is preferably 10 to 3000 nm.

[0162] An oriented polymer layer can be formed by applying a composition in which an oriented polymer is dissolved in a solvent to a substrate layer, removing the solvent, and performing a rubbing treatment as necessary. In this case, the orientation restrictive force in the oriented polymer layer formed from the oriented polymer can be arbitrarily adjusted according to the surface condition of the oriented polymer or the rubbing conditions.

[0163] A photooriented polymer layer can be formed by applying a composition comprising a solvent and a polymer or monomer having photoreactive groups to a substrate layer and irradiating it with polarized light. In this case, the orientation restrictive force in the photooriented polymer layer can be arbitrarily adjusted according to the polarized light irradiation conditions for the photooriented polymer.

[0164] The groove orientation layer can be formed by, for example, a method of forming an uneven pattern by performing exposure and development through an exposure mask having a pattern-shaped slit on the surface of a photosensitive polyimide film; a method of forming an uncured layer of an active energy beam curable resin on a plate-shaped disc having grooves on its surface and transferring this layer to a substrate layer to cure it; or a method of forming an uncured layer of an active energy beam curable resin on a substrate layer and forming and curing the unevenness by pressing a roll-shaped disc having unevenness onto this layer.

[0165] (First liquid crystal layer and second liquid crystal layer)

[0166] The first liquid crystal layer and the second liquid crystal layer (hereinafter, both may be collectively referred to as the "liquid crystal layer") may be formed using a liquid crystal compound, such as a known polymerizable liquid crystal compound. The type of liquid crystal compound is not particularly limited, and rod-shaped liquid crystal compounds, disc-shaped liquid crystal compounds, and mixtures thereof may be used. When using a liquid crystal compound, a composition for forming a liquid crystal layer, comprising a liquid crystal compound, a solvent, and various additives as needed, may be applied onto an alignment layer to form a film, and by solidifying (curing) this film, a liquid crystal layer, which is a liquid crystal cured layer, may be formed. Alternatively, a composition for forming a liquid crystal layer may be applied onto a substrate layer to form a film, and the liquid crystal layer may be formed by stretching this film together with the substrate layer. The liquid crystal layer may be a phase difference layer.

[0167] The composition for forming a liquid crystal layer may include, in addition to the liquid crystal compound and solvent described above, a polymerization initiator, a reactive additive, a leveling agent, a polymerization inhibitor, etc. The liquid crystal compound, solvent, polymerization initiator, reactive additive, leveling agent, polymerization inhibitor, etc., may appropriately utilize known materials.

[0168] (Resin film)

[0169] The resin film may be an optical functional film or a separator covering an adhesive layer. Examples of optical functional films include the second liquid crystal layer, a polarizing layer, a polarizing plate having a protective layer formed on at least one surface of the polarizing layer, a polarizing plate with a protective film attached having a protective film laminated on at least one surface of the polarizing plate, a reflective film, a semi-transparent reflective film, a brightness enhancement film, an optical compensation film, a film having an anti-glare function, a phase difference film, etc. It may have one of these, or it may have a multilayer structure having two or more. In addition, if the optical functional layer includes a liquid crystal layer, the liquid crystal layer may be a phase difference layer or a polarizing layer. In this specification, "polarizing layer" refers to a layer having the property of transmitting linearly polarized light having a vibration plane orthogonal to the absorption axis when unpolarized light is incident.

[0170] As a polarizing layer that may be included in an optical functional film, it may be a single-layer polyvinyl alcohol resin film in which a dichromatic pigment is adsorbed and oriented, or a laminated film of two or more layers having a polyvinyl alcohol resin layer in which a dichromatic pigment is adsorbed and oriented on a substrate film. In addition, the polarizing layer may be a cured film formed by oriented a dichromatic pigment in a liquid crystal compound and polymerizing the liquid crystal compound.

[0171] Examples of separators include films on which a release treatment, such as silicone treatment, is applied to the surface of the substrate film.

[0172] (Adhesive layer and other adhesive layers)

[0173] The adhesive layer and other adhesive layers (hereinafter simply referred to as "adhesive layer") may be formed by an adhesive, a pressure-sensitive adhesive, or a combination thereof, and are typically one layer, but may have two or more layers. When the adhesive layer includes two or more layers, each layer may be formed of the same material or may be formed of different materials.

[0174] As an adhesive, it may be formed by combining one or more types among, for example, water-based adhesives, active energy beam curing adhesives, and pressure-sensitive adhesives. Examples of water-based adhesives include an aqueous solution of a polyvinyl alcohol-based resin and a water-based two-component urethane-based emulsion adhesive. An active energy beam curing adhesive is an adhesive that cures by irradiating with active energy rays such as ultraviolet rays, and examples include those containing a polymerizable compound and a photopolymerization initiator, those containing a photoreactive resin, and those containing a binder resin and a photoreactive crosslinking agent. Examples of the polymerizable compound include photopolymerizable monomers such as photocurable epoxy monomers, photocurable acrylic monomers, and photocurable urethane monomers, or oligomers derived from these monomers. Examples of the photopolymerization initiator include a substance that generates active species such as neutral radicals, anionic radicals, and cationic radicals by irradiating with active energy rays such as ultraviolet rays.

[0175] Examples of adhesives include compositions in which (meth)acrylic resins, styrene resins, silicone resins, etc. are used as base polymers, and crosslinking agents such as isocyanate compounds, epoxy compounds, and aziridine compounds are added.

[0176] The adhesive layer is preferably formed using an active energy beam curable adhesive, and in particular, it is preferably formed using an adhesive comprising a UV-curable epoxy monomer and a photocationic polymerization initiator.

[0177] Surface treatments such as corona treatment, plasma treatment, and flame treatment may be performed on the surface of the layer on which the adhesive layer is formed, as needed. Explanation of the symbols

[0178] 10: Optical film 11: First layer of material 12: First liquid crystal layer 12a: First stage region 12b: First adjacent area 20: Resin Film 21: Second layer of material 22: Second liquid crystal layer 22a: Second stage area 22b: Second adjacent area 30~32: Adhesive layer

Claims

Claim 1 An optical film comprising a first liquid crystal layer, wherein the first liquid crystal layer has a first end region including one end in the width direction and a first adjacent region adjacent to the first end region in the width direction, and the first end region and the first adjacent region satisfy at least one of the following relationships [a1] and [b1]. [a1] The reflectance of the first end region and the reflectance of the first adjacent region are different from each other. [b1] The transmittance of the first end region and the transmittance of the first adjacent region are different from each other. Claim 2 In claim 1, the first terminal region and the first adjacent region are an optical film satisfying at least one of the following relationships [a2] and [b2]. [a2] The reflectance of the first terminal region is higher than the reflectance of the first adjacent region. [b2] The transmittance of the first terminal region is lower than the transmittance of the first adjacent region. Claim 3 In claim 1 or 2, the first terminal region and the first adjacent region are optical films in which at least one value among haze, brightness, reflective color, color difference, and polarization degree is different. Claim 4 In any one of claims 1 to 3, the first terminal region is an optical film comprising both ends in the width direction of the first liquid crystal layer. Claim 5 An optical film according to any one of claims 1 to 4, wherein the first adjacent region is the entire region other than the first terminal region in the first liquid crystal layer. Claim 6 An optical film comprising a first substrate layer in any one of claims 1 to 5. Claim 7 An optical film according to any one of claims 1 to 5, further comprising an adhesive layer and a resin film, wherein the first liquid crystal layer, the adhesive layer, and the resin film are included in this order. Claim 8 An optical film according to claim 6, further comprising an adhesive layer and a resin film, wherein the first substrate layer, the first liquid crystal layer, the adhesive layer and the resin film are included in this order. Claim 9 In claim 7 or 8, the resin film is an optical film comprising a polarizing layer. Claim 10 In any one of claims 7 to 9, the resin film is an optical film comprising a second liquid crystal layer. Claim 11 In claim 10, the second liquid crystal layer comprises a second end region including one end in the width direction and a second adjacent region adjacent to the second end region in the width direction, and the second end region and the second adjacent region are optical films satisfying at least one of the following [c1] and [d1]. [c1] The reflectance of the second end region and the reflectance of the second adjacent region are different from each other. [d1] The transmittance of the second end region and the transmittance of the second adjacent region are different from each other. Claim 12 In claim 11, the second terminal region and the second adjacent region are an optical film satisfying at least one of the following relationships [c2] and [d2]. [c2] The reflectance of the second terminal region is higher than the reflectance of the second adjacent region. [d2] The transmittance of the second terminal region is lower than the transmittance of the second adjacent region. Claim 13 In claim 11 or 12, the resin film further comprises a second substrate layer, and the second substrate layer is an optical film provided on the side opposite to the adhesive layer side of the second liquid crystal layer.

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