Long retardation film, long optical film, long polarizing film, method for manufacturing long retardation film, and method for manufacturing long optical film

Abstract

To solve the problem in which: in a long polarizing film, burr may occur at the ends in a width direction of a transferred phase difference layer; the occurrence of burr leads to mixing of foreign substances in the long polarizing film and contamination of a manufacturing line with the foreign substance.SOLUTION: A long phase difference film including a longitudinal direction and a short direction includes a base material and a phase difference layer placed on the base material. The phase difference layer includes a first area, a pair of second areas, and a pair of third areas. The first area is located between the pair of second areas in the short direction. The pair of second areas are located between the pair of third areas in the short direction. the phase difference layer includes a cured product of a liquid crystal composition. The second area is non-oriented. The third area is horizontally oriented.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a long retardation film, a long optical film, a long polarizing film, a method for producing a long retardation film, and a method for producing a long optical film. [Background technology]

[0002] Retardation films and polarizing films are applied to display devices such as organic electroluminescence (EL) displays and liquid crystal displays. As disclosed in Patent Document 1, a retardation film can be produced by applying a polymerizable liquid crystal composition onto a substrate to form a coating film on the substrate and curing the coating film. A long retardation film can be produced by forming a long coating film on a long substrate and curing the coating film. A long polarizing film can be produced by using a long retardation film. The roll-to-roll production method is excellent in terms of production efficiency and production cost. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-184046 A Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, a long polarizing film is manufactured by transferring a retardation layer of a long retardation film to a long transfer film. In the long polarizing film manufactured in this manner, burrs may occur at the end of the transferred retardation layer in the width direction. When burrs occur, foreign matter is mixed into the long polarizing film, and the manufacturing line is contaminated by the foreign matter. The present disclosure aims to suppress the occurrence of burrs at the end of the retardation layer. [Means for solving the problem]

[0005] The long retardation film according to one embodiment of the present disclosure is A long retardation film including a longitudinal direction and a transverse direction, A substrate; A retardation layer overlapped with the base material, The retardation layer includes a first region, a pair of second regions, and a pair of third regions, the first region is located between the pair of second regions in the short-side direction, the pair of second regions are located between the pair of third regions in the short-side direction, The retardation layer includes a cured product of a liquid crystal composition, The second region is non-oriented, The third region is horizontally aligned.

[0006] The long optical film according to one embodiment of the present disclosure comprises: A long optical film including a longitudinal direction and a transverse direction, A substrate, a bonding layer, and a retardation layer are provided in this order. The retardation layer includes a first region and a pair of second regions, the first region is located between the pair of second regions in the short-side direction, The retardation layer includes a cured product of a liquid crystal composition, The second region is non-oriented.

[0007] In one embodiment of the present disclosure, the long polarizing film is A long polarizing film including a longitudinal direction and a transverse direction, a polarizing layer including a polarizer; A retardation layer overlapped with the polarizing layer, The retardation layer includes a first region and a pair of second regions, the first region is located between the pair of second regions in the short-side direction, The retardation layer includes a cured product of a liquid crystal composition, The second region is non-oriented.

[0008] A method for producing a long retardation film according to an embodiment of the present disclosure includes: A step of applying an alignment film-forming composition to a long substrate having a longitudinal direction and a transverse direction to form a first coating film; a step of irradiating a central region of the first coating film, excluding end regions in the short side direction, with polarized light to form an alignment film from the first coating film, the central region of which has an alignment regulating force; applying a liquid crystal composition to an intermediate including the substrate and the alignment film to form a second coating film; and curing the second coating film to form a retardation layer including a cured product of the liquid crystal composition. the retardation layer includes a first region facing the central region, a second region facing the edge region, and a third region facing the base material on the outer side of the alignment film in the short-side direction, The third region is horizontally aligned.

[0009] A method for producing a long optical film according to an embodiment of the present disclosure includes the steps of: A step of laminating a long retardation film according to an embodiment of the present disclosure onto a long transfer film including a bonding layer; and peeling off the base material from the long retardation film bonded to the bonding layer. Effect of the Invention

[0010] According to the present disclosure, it is possible to suppress the occurrence of burrs on the ends of the retardation layer. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram for explaining an embodiment, and is a vertical sectional view showing an example of a long retardation film. [Diagram 2] FIG. 2 is a plan view showing an example of the long retardation film of FIG. [Diagram 3] FIG. 3 is a perspective view showing an example of a long retardation film, a transferred film, a long optical film, and a long polarizing film. [Figure 4] FIG. 4 is a partially enlarged view of FIG. [Diagram 5] FIG. 5 is a diagram for explaining an example of a method for producing the long retardation film of FIG. [Figure 6] FIG. 6 is a diagram for explaining the manufacturing method of FIG. [Figure 7] FIG. 7 is a diagram for explaining the manufacturing method of FIG. [Figure 8] FIG. 8 is a diagram for explaining the manufacturing method of FIG. [Figure 9] FIG. 9 is a diagram for explaining the manufacturing method of FIG. [Figure 10] FIG. 10 is a diagram for explaining the manufacturing method of FIG. [Figure 11] FIG. 11 is a vertical cross-sectional view showing an example of a long optical film and a long polarizing film produced by using the long retardation film of FIG. [Figure 12] FIG. 12 is a longitudinal sectional view showing an example of a transfer film used in producing the long optical film and the long polarizing film of FIG. [Figure 13] FIG. 13 is a diagram illustrating an example of a method for producing the long optical film and the long polarizing film of FIG. [Figure 14] FIG. 14 is a diagram for explaining the manufacturing method of FIG. [Figure 15] FIG. 15 is a diagram for explaining the manufacturing method of FIG. [Figure 16] FIG. 16 is a diagram for explaining the manufacturing method of FIG. [Figure 17] FIG. 17 is a diagram showing an application example of an optical film and a polarizing film obtained from the long optical film and the long polarizing film of FIG. [Figure 18] FIG. 18 is a diagram showing another application example of the optical film and the polarizing film. [Figure 19] FIG. 19 is a cross-sectional view showing the long retardation film according to Example 1 together with a transfer film. [Figure 20] FIG. 20 is a cross-sectional view showing the long retardation film according to Comparative Example 1 together with the transfer film. [Figure 21]FIG. 21 is a cross-sectional view showing a long retardation film according to Comparative Example 2 together with a transfer film. [Figure 22] FIG. 22 is a photograph showing the long optical film according to Example 1. As shown in FIG. [Figure 23] FIG. 23 is a photograph showing a long optical film according to Comparative Example 1. As shown in FIG. [Figure 24] FIG. 24 is a photograph showing a long optical film according to Comparative Example 2. As shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] One embodiment of the present disclosure relates to the following [1] to

[35] .

[0013] [1] A long retardation film including a longitudinal direction and a transverse direction, A substrate; A retardation layer overlapped with the base material, The retardation layer includes a first region, a pair of second regions, and a pair of third regions, the first region is located between the pair of second regions in the short-side direction, the pair of second regions are located between the pair of third regions in the short-side direction, The retardation layer includes a cured product of a liquid crystal composition, The second region is non-oriented, The third region is a long retardation film having a horizontal alignment.

[0014] [2] The third region has a third slow axis, The long retardation film according to [1], wherein a third orientation angle between the third slow axis and the longitudinal direction is 40° or more and 140° or less.

[0015] [3] The first region has a first slow axis, The long retardation film according to [1] or [2], wherein a first orientation angle between the first slow axis and the longitudinal direction is 10° or more and 80° or less, or 100° or more and 170° or less.

[0016] [4] The long retardation film according to any one of [1] to [3], wherein the third region includes an end portion of the retardation layer in the short-side direction.

[0017] [5] The long retardation film according to any one of [1] to [4], wherein the first region includes a center of the retardation layer in the short-side direction.

[0018] [6] An alignment film is provided between the substrate and the first and second regions; The long retardation film according to any one of [1] to [5], wherein the third region is in contact with the base material.

[0019] [7] The long retardation film according to [6], wherein the alignment film includes a photo-alignment film.

[0020] [8] The long retardation film according to claim 1, wherein the substrate comprises a polyethylene film.

[0021] [9] The polyethylene film has a slow axis, The long retardation film according to [8], wherein an angle between the slow axis and the longitudinal direction of the polyethylene film is 40° or more and 140° or less.

[0022]

[10] The long retardation film according to any one of [1] to [9], wherein the length of the second region along the short side direction is 1 mm or more and 200 mm or less.

[0023]

[11] The long retardation film according to any one of [1] to

[10] , wherein the third region has a length along the short side direction of 0.5 mm or more and 50 mm or less.

[0024]

[12] The long retardation film according to any one of [1] to

[11] , wherein the length of the first region along the short side direction is six times or more the length of the second region along the short side direction.

[0025]

[13] An in-plane retardation Re(450) of the retardation layer in the first region at a wavelength of 450 nm is smaller than an in-plane retardation Re(550) of the retardation layer in the first region at a wavelength of 550 nm; the in-plane retardation Re(550) is smaller than the in-plane retardation Re(650) in the first region of the retardation layer at a wavelength of 650 nm; The long retardation film according to any one of [1] to

[12] , wherein the in-plane retardation Re(550) is 130 nm or more and 153 nm or less.

[0026]

[14] A long optical film having a longitudinal direction and a transverse direction, A substrate, a bonding layer, and a retardation layer are provided in this order. The retardation layer includes a first region and a pair of second regions, the first region is located between the pair of second regions in the short-side direction, The retardation layer includes a cured product of a liquid crystal composition, The second region is non-oriented.

[0027]

[15] A long polarizing film including a longitudinal direction and a transverse direction, a polarizing layer including a polarizer; A retardation layer overlapped with the polarizing layer, The retardation layer includes a first region and a pair of second regions, the first region is located between the pair of second regions in the short-side direction, The retardation layer includes a cured product of a liquid crystal composition, The second region is non-oriented.

[0028]

[16] The first region has a first slow axis, The long polarizing film of

[15] , wherein a first orientation angle between the first slow axis and the longitudinal direction is 10° or more and 80° or less, or 100° or more and 170° or less.

[0029]

[17] The long polarizing film according to

[15] or

[16] , wherein the second region includes an end portion of the retardation layer in the short-side direction.

[0030]

[18] The long polarizing film according to any one of

[15] to

[17] , wherein the first region includes a center of the retardation layer in the short-side direction.

[0031]

[19] The long polarizing film of any one of

[15] to

[18] , wherein the length of the second region along the short side direction is 1 mm or more and 100 mm or less.

[0032]

[20] The long polarizing film of any of

[15] to

[19] , wherein the length of the first region along the short side direction is at least 12 times the length of the second region along the short side direction.

[0033]

[21] An in-plane retardation Re(450) of the retardation layer in the first region at a wavelength of 450 nm is smaller than an in-plane retardation Re(550) of the retardation layer in the first region at a wavelength of 550 nm; the in-plane retardation Re(550) is smaller than the in-plane retardation Re(650) in the first region of the retardation layer at a wavelength of 650 nm; The long polarizing film according to any one of

[15] to

[20] , wherein the in-plane retardation Re(550) is 130 nm or more and 153 nm or less.

[0034]

[22] A step of applying an alignment film-forming composition to a long substrate having a longitudinal direction and a transverse direction to form a first coating film; a step of irradiating a central region of the first coating film, excluding end regions in the short side direction, with polarized light to form an alignment film from the first coating film, the central region of which has an alignment regulating force; applying a liquid crystal composition to an intermediate including the substrate and the alignment film to form a second coating film; and curing the second coating film to form a retardation layer including a cured product of the liquid crystal composition. the retardation layer includes a first region facing the central region, a second region facing the edge region, and a third region facing the base material on the outer side of the alignment film in the short-side direction, The method for producing a long retardation film, wherein the third region is horizontally aligned.

[0035]

[23] The third region has a third slow axis, The method for producing a long retardation film according to

[22] , wherein a third orientation angle between the third slow axis and the longitudinal direction is 40° or more and 140° or less.

[0036]

[24] The first region has a first slow axis, The method for producing a long retardation film according to

[22] or

[23] , wherein a first orientation angle between the first slow axis and the longitudinal direction is 10° or more and 80° or less, or 100° or more and 170° or less.

[0037]

[25] The method for producing a long retardation film according to any one of

[22] to

[24] , wherein the third region includes an end portion of the retardation layer in the short-side direction.

[0038]

[26] The method for producing a long retardation film according to any one of

[22] to

[25] , wherein the first region includes a center of the retardation layer in the short-side direction.

[0039]

[27] The substrate comprises a polyethylene film having a slow axis; The method for producing a long retardation film according to any one of

[22] to

[26] , wherein an angle between the slow axis and the longitudinal direction of the polyethylene film is 40° or more and 140° or less.

[0040]

[28] The method for producing a long retardation film according to any one of

[22] to

[27] , wherein the length of the second region along the short side direction is 1 mm or more and 200 mm or less.

[0041]

[29] The method for producing a long retardation film according to any one of

[22] to

[28] , wherein the third region has a length along the short side direction of 0.5 mm or more and 50 mm or less.

[0042]

[30] The method for producing a long retardation film according to any one of

[22] to

[29] , wherein the length of the first region along the short side direction is six times or more the length of the second region along the short side direction.

[0043]

[31] An in-plane retardation Re(450) of the retardation layer in the first region at a wavelength of 450 nm is smaller than an in-plane retardation Re(550) of the retardation layer in the first region at a wavelength of 550 nm; the in-plane retardation Re(550) is smaller than the in-plane retardation Re(650) in the first region of the retardation layer at a wavelength of 650 nm; The method for producing a long retardation film according to any one of

[22] to

[30] , wherein the in-plane retardation Re(550) is 130 nm or more and 153 nm or less.

[0044]

[32] A step of laminating a long retardation film according to any one of [1] to

[13] onto a long transfer film including a bonding layer; and peeling off the base material from the long retardation film bonded to the bonding layer.

[0045]

[33] The long optical film includes the first region and a part of the second region of the retardation layer, The method for producing a long optical film according to

[32] , wherein the third region of the retardation layer and a remainder other than the part of the second region remain on the base.

[0046]

[34] The method for producing a long optical film described in

[32] or

[33] , wherein, when the long retardation film is laminated on the transfer film, the second region faces an end of the bonding layer in the short side direction, and the third region is located outside the bonding layer in the short side direction and faces the substrate of the transfer film.

[0047]

[35] The method for producing a long optical film according to any one of

[32] to

[34] , wherein the film to be transferred comprises a polarizing layer including a polarizer.

[0048] Hereinafter, an embodiment of the present disclosure will be described in detail. In the drawings accompanying this specification, the scale and the aspect ratio are appropriately changed and exaggerated from those of the actual objects for the convenience of illustration and ease of understanding.

[0049] In this specification, terms such as "film", "sheet" and "plate" are not distinguished from each other based only on the difference in name. For example, a "retardation film" cannot be distinguished from a member called a retardation sheet or a retardation plate only on the difference in name. A "polarizing film" cannot be distinguished from a member called a polarizing sheet or a polarizing plate only on the difference in name.

[0050] "Film surface (sheet surface, plate surface)" refers to a surface that coincides with the planar direction of the target film-like (sheet-like, plate-like) member when the target film-like (sheet-like, plate-like) member is viewed overall and in a global perspective. The normal direction to the film-like (sheet-like, plate-like) member refers to the normal direction to the film surface (sheet surface, plate surface) of the film-like (sheet-like, plate-like) member.

[0051] In this specification, when multiple upper limit candidates and multiple lower limit candidates are given for a certain parameter, the numerical range of the parameter may be formed by combining any one of the upper limit candidates and any one of the lower limit candidates. As an example, consider the description "Parameter B may be A1 or more, A2 or more, or A3 or more. Parameter B may be A4 or less, A5 or less, or A6 or less." In this example, the numerical range of parameter B may be A1 or more and A4 or less, A1 or more and A5 or less, A1 or more and A6 or less, A2 or more and A4 or less, A2 or more and A5 or less, A2 or more and A6 or less, A3 or more and A4 or less, A3 or more and A5 or less, or A3 or more and A6 or less.

[0052] In order to clarify the relationship between directions between the drawings, some drawings show a common first direction D1, a second direction D2, and a third direction D3 by arrows with common symbols. The tip side of the arrow is the first side of each direction. The side opposite the tip of the arrow is the second side of each direction. An arrow pointing into the paper in a direction perpendicular to the paper surface of the drawing is shown by a symbol with an x ​​in a circle, as shown in Figure 1, for example. An arrow pointing out from the paper in a direction perpendicular to the paper surface of the drawing is shown by a symbol with a dot in a circle, as shown in Figure 2, for example.

[0053] 1 and 12 are hatched to show cross sections. Hatching is omitted in the other figures. Also, in Figures 8 to 11, 14, 16, and 19 to 21, hatching is used to show the alignment regulating force of the alignment film 30 and the alignment state of the retardation layer 40. The hatching in Figures 8 to 11, 14, 16, and 19 to 21 does not show cross sections.

[0054] <<Long Retardation Film 10>> 1 to 3 show an example of the long retardation film 10 according to the present embodiment. As shown in FIG. 1 and FIG. 2, the long retardation film 10 has a longitudinal direction and a transverse direction. The transverse direction may be perpendicular to the long retardation direction. In the drawings, the long direction of the long retardation film 10 is shown as the second direction D2. The transverse direction of the long retardation film 10 is shown as the first direction D1. The long retardation film 10 spreads in the first direction D1 and the second direction D2. The normal direction of the long retardation film 10 is shown as the third direction D3. The third direction D3 is the thickness direction of the long retardation film 10. The first direction D1 and the second direction D2 may be perpendicular to each other. The third direction D3 may be perpendicular to the first direction D1. The third direction D3 may be perpendicular to the second direction D2.

[0055] As shown in Fig. 3, the long retardation film 10 can be handled as a roll 10R wound around a winding core 12 with the winding axis RA as the center. This improves the handleability of the long retardation film 10. As described later, the long retardation film 10 can be manufactured by a roll-to-roll manufacturing method. The long retardation film 10 is excellent in terms of production efficiency and manufacturing cost.

[0056] As shown in FIG. 4, the long retardation film 10 according to the present embodiment includes a substrate 20 and a retardation layer 40 laminated on the substrate 20. The substrate 20 is long. The retardation layer 40 is long. The retardation layer 40 includes a first region 41, a pair of second regions 42, and a pair of third regions 43. The first region 41 is located between the pair of second regions 42 in the short side direction. The pair of second regions 42 are located between the pair of third regions 43 in the short side direction. The retardation layer 40 includes a cured product of a liquid crystal composition. The second region 42 is non-aligned. The third region 43 has horizontal alignment.

[0057] "Long" means that the object, such as a film, has a length of 5 m or more when unfolded, may have a length of 10 m or more, or may have a length of 100 m or more. The term "longitudinal direction" refers to the direction along the longest edge of an object such as a film when it is unfolded. The term "transverse direction" refers to the direction along which the object such as a film has the shortest length when it is unfolded.

[0058] As described later, the long retardation film 10 is laminated on a long transfer film 50 including a bonding layer 53, and then the substrate 20 is peeled off from the long retardation film 10 bonded to the bonding layer 53, thereby transferring the retardation layer 40P to the transfer film 50. At this time, the generation of burrs on the end E40P in the short direction of the retardation layer 40P transferred to the transfer film 50 can be suppressed.

[0059] In the illustrated example, the long retardation film 10 further includes an alignment film 30. The alignment film 30 is located between the substrate 20 and the retardation layer 40 in the third direction D3. The alignment film 30 is long. Hereinafter, each layer of the long retardation film 10 will be described with reference to the drawings.

[0060] <Retardation layer 40> The retardation layer 40 includes a cured product of a liquid crystal composition. The liquid crystal composition includes a liquid crystal compound. The liquid crystal composition may be a liquid crystal composition that undergoes a polymerization reaction, that is, a polymerizable liquid crystal composition. The liquid crystal composition may include a polymerizable liquid crystal compound. The retardation layer 40 may include a polymerizable liquid crystal compound. The retardation layer 40 can be obtained by forming a coating film by applying a liquid crystal composition, and then curing the liquid crystal composition. The orientation state of the liquid crystal compound in the coating film may be adjusted to horizontal orientation, vertical orientation, tilted orientation, twisted orientation, hybrid orientation, or the like. By adjusting the orientation of the liquid crystal compound in the coating film, the optical characteristics of each region in the retardation layer 40 can be controlled. The orientation of the liquid crystal compound in each region of the retardation layer 40 will be described later.

[0061] The polymerizable liquid crystal compound is not particularly limited. The polymerizable liquid crystal compound may be a polymerizable liquid crystal compound used to form a layer having birefringence. The polymerizable liquid crystal compound is appropriately selected according to the retardation value, wavelength dispersion, orientation, solubility, etc. desired for the retardation layer 40.

[0062] The polymerizable liquid crystal compound is a liquid crystal compound having a polymerizable group. The polymerizable liquid crystal compound contains a polymerizable functional group in the molecule. The polymerizable functional group allows the liquid crystal compound to be polymerized and fixed, so that the alignment stability is excellent and the change in retardation over time can be reduced. The polymerizable liquid crystal compound may be a monofunctional liquid crystal compound containing a single polymerizable functional group. The polymerizable liquid crystal compound may be a polyfunctional liquid crystal compound containing two or more polymerizable functional groups. By having two or more polymerizable functional groups, the three-dimensional alignment of the liquid crystal compound becomes more stable and the change in retardation over time can be further reduced. The polymerizable liquid crystal compound may be a polyfunctional liquid crystal compound containing three polymerizable functional groups. The polymerizable liquid crystal compound may be a polyfunctional liquid crystal compound containing two polymerizable functional groups. The polymerizable functional group may be polymerized by ionizing radiation such as ultraviolet light or an electron beam. The polymerizable functional group may be polymerized by the action of heat. The polymerizable liquid crystal compound may be a low molecular liquid crystal compound. The polymerizable liquid crystal compound may be a high molecular liquid crystal compound.

[0063] The polymerizable functional group may be a radically polymerizable functional group. An example of the radically polymerizable functional group is a functional group having at least one ethylenically unsaturated double bond capable of addition polymerization. Specific examples of the polymerizable functional group include a vinyl group with or without a substituent, an acrylate group (a general term including an acryloyl group, a methacryloyl group, an acryloyloxy group, and a methacryloyloxy group), and the like.

[0064] The polymerizable functional group may be a cationic polymerizable functional group. Specific examples of the polymerizable functional group include an alicyclic ether group (such as an epoxy group or an oxetanyl group), a cyclic acetal group, a cyclic lactone group, a cyclic imino ether group, a cyclic thioether group, a spiro orthoester group, and a vinyloxy group.

[0065] The polymerizable liquid crystal composition may contain a single polymerizable liquid crystal compound. The polymerizable liquid crystal composition may contain two or more polymerizable liquid crystal compounds. By combining two or more polymerizable liquid crystal compounds, the retardation value, wavelength dispersion, alignment, solubility, phase transition temperature, etc. can be adjusted.

[0066] The polymerizable liquid crystal composition may contain one or more materials such as a polymerizable compound having no liquid crystallinity, a photopolymerization initiator, a sensitizer, a leveling agent, an antioxidant, and a light stabilizer.

[0067] The wavelength dispersion of the retardation layer 40 may be reverse dispersion. Reverse dispersion means that the in-plane retardation Re increases from the short wavelength side to the long wavelength side. By making the wavelength dispersion of the retardation layer 40 reverse dispersion, the fluctuation of the in-plane retardation Re according to the wavelength can be suppressed, and the color expression is excellent. Examples of polymerizable liquid crystal compounds exhibiting reverse dispersion include those represented by general formula (1) in JP2019-73712A and those represented by general formula (II) in International Publication No. WO2017 / 043438.

[0068] The retardation layer 40 having reverse dispersion may have the following optical characteristics with respect to the in-plane retardation in the first region 41. Re(450) <Re(550) Re(550) <Re(650) Re(450) is the in-plane retardation in the first region 41 of the retardation layer 40 at a wavelength of 450 nm. Re(550) is the in-plane retardation in the first region 41 of the retardation layer 40 at a wavelength of 550 nm. Re(650) is the in-plane retardation in the first region 41 of the retardation layer 40 at a wavelength of 650 nm.

[0069] Re(450), Re(550), and Re(650) in the first region 41 of the retardation layer 40 are not particularly limited. In an example in which the first region 41 of the retardation layer 40 is a λ / 4 retardation layer, Re(450), Re(550), and Re(650) may be 90 nm or more, 100 nm or more, or 110 nm or more. In an example in which the first region 41 of the retardation layer 40 is a λ / 4 retardation layer, Re(450), Re(550), and Re(650) may be 180 nm or less, 160 nm or less, or 150 nm or less. In an example in which the first region 41 of the retardation layer 40 is a λ / 4 retardation layer, the in-plane retardation Re(550) may be 130 nm or more, 133 nm or more, or 136 nm or more. In an example in which the first region 41 of the retardation layer 40 is a λ / 4 retardation layer, the in-plane retardation Re(550) may be 153 nm or less, 150 nm or less, or 147 nm or less. By setting the in-plane retardation in the first region 41 of the retardation layer 40 in this manner, the first region 41 of the retardation layer 40 can be used as a circular polarizing plate in combination with a polarizer.

[0070] The thickness of the retardation layer 40 along the third direction D3 may be 0.1 μm or more, 0.5 μm or more, or 1.5 μm or more. The thickness of the retardation layer 40 may be 5.0 μm or less, 4.0 μm or less, or 3.0 μm or less. By setting the thickness of the retardation layer 40 in this manner, the above-mentioned in-plane retardation appropriate for a λ / 4 retardation layer can be imparted to the first region 41 of the retardation layer 40.

[0071] The thicknesses of the components constituting the retardation layer 40 and the long retardation film 10, and the thicknesses of the components constituting the transfer film 50 and the long optical film 55 described below are the average values ​​of measured values ​​at 20 points in images of the long retardation film 10, the transfer film 50, etc. observed by a scanning transmission electron microscope (STEM).

[0072] The in-plane phase difference is the average value of the measured values ​​at 16 points. The 16 measurement points are the centers of measurement when lines are drawn to divide the area inside the margin into 5 equal parts vertically and horizontally, with a margin of 1 cm from the outer edge of the measurement sample. When the measurement sample is rectangular, the measurement is performed with the 16 intersections of the lines dividing the area inside the margin into 5 equal parts vertically and horizontally, with a margin of 1 cm from the outer edge of the rectangle, as the center, and the in-plane phase difference of the measurement sample is determined by calculating the average value. When the measurement sample is a shape other than a rectangle, such as a circle, an ellipse, a triangle, or a pentagon, a square or rectangle with the maximum area inscribed in these shapes is specified, and 16 measurements are performed on the square or rectangle using the above method. The in-plane phase difference is measured using a product name "RETS-100" manufactured by Otsuka Electronics Co., Ltd.

[0073] The in-plane retardation Re is measured using the RETS-100 in accordance with the following steps (A1) to (A4). (A1) First, turn on the RETS-100 light source and leave it for 60 minutes or more to stabilize it. Then, select the rotating analyzer method and the θ mode. By selecting this θ mode, the stage becomes a tilting rotating stage. (A2) Next, enter the following measurement conditions into the RETS-100. (Measurement conditions) Retardation measurement range: Rotating analyzer method Measurement spot diameter: φ5mm Tilt angle range: 0° Measurement wavelength range: 400nm~800nm -Average refractive index of the layer to be measured (for example, N=1.617 for PET film) Thickness: Thickness measured separately by STEM (A3) Next, background data is obtained without placing a sample in the instrument, in a closed system, and every time the light source is turned on. (A4) After that, the sample is placed on the stage inside the device and measured.

[0074] When the object to be measured for in-plane retardation does not have a sufficient size due to a narrow width or the like, a measurement sample having a sufficient size is prepared under the same conditions as the object to be measured, and the in-plane retardation measured for this measurement sample is used as the in-plane retardation of the object to be measured.

[0075] <Base material 20> The substrate 20 supports the retardation layer 40. In the illustrated example, the substrate 20 also supports the alignment film 30. The substrate 20 may be transparent. Transparent means that the total light transmittance in accordance with JIS K7361-1:1997 is 50% or more, and may be 70% or more, 80% or more, or 90% or more. When the long retardation film 10 is manufactured by a roll-to-roll method, the substrate 20 may have flexibility that allows it to be wound into a roll.

[0076] Resin may be used as the material of the substrate 20. The substrate 20 made of resin has flexibility and is suitable for a roll-to-roll manufacturing method. Examples of materials for the substrate 20 include polyethylene terephthalate, polyurethane, polyimide, polyamide, polycarbonate, polyethylene naphthalate, polymethyl methacrylate, and polymethyl acrylate.

[0077] The biaxially stretched polyethylene film has high transparency and excellent mechanical properties. The biaxially stretched polyethylene film may have birefringence. As described later, the biaxially stretched polyethylene film can exert an orientation regulating force on the liquid crystal compound contained in the liquid crystal composition for forming the retardation layer 40. In many resin substrates such as polyethylene films, the stretching axis is the slow axis. In many resin substrates such as biaxially stretched polyethylene films, the stretching direction with the largest stretching ratio is the slow axis. The resin film is usually stretched in the longitudinal direction and the transverse direction perpendicular to the longitudinal direction. The stretching ratio in the transverse direction is larger than the stretching ratio in the longitudinal direction. The orientation angle θ20 of the slow axis of the biaxially stretched resin substrate 20 with respect to the longitudinal direction may be 40° or more, 50° or more, 60° or more, 70° or more, or 80° or more. The orientation angle θ20 may be 140° or less, 130° or less, 120° or less, 110° or less, or 100° or less. The orientation angle θ20 may be 90°. As shown in FIG. 4, the orientation angle is the magnitude of the angle between the slow axis and the longitudinal direction (second direction D2). The orientation angle is the magnitude of the angle that the slow axis makes in the counterclockwise direction with respect to the reference axis AS, which is an axis extending on one side in the longitudinal direction. The orientation angle is specified as an angle equal to or greater than 0° and less than 180°. In the example shown in FIG. 4, the reference axis AS faces the first side in the second direction D2.

[0078] The substrate 20 may contain one or more of a flame retardant, an antiblocking agent, an antioxidant, a light stabilizer, a tackifier, an antistatic agent, and the like in the binder resin made of the above-mentioned materials.

[0079] The thickness of the substrate 20 along the third direction D3 may be 10 μm or more, 25 μm or more, or 30 μm or more. The thickness of the substrate 20 may be 1000 μm or less, 200 μm or less, or 150 μm or less.

[0080] The surface of the substrate 20 facing the alignment film 30 and the retardation layer 40 may not be surface-treated. When the retardation layer 40 is transferred to the transfer film 50 as described later, the substrate 20 having the untreated surface can be easily peeled off from the long retardation film 10. The surface of the substrate 20 not facing the alignment film 30 and the retardation layer 40 may be surface-treated.

[0081] <Alignment film 30> As shown in Fig. 1 and Fig. 2, the long retardation film 10 includes an alignment film 30 between a substrate 20 and a retardation layer 40. The alignment film 30 has an alignment regulating force. The alignment film 30 adjusts the alignment of the retardation layer 40. The alignment film 30 aligns the liquid crystal compound contained in the retardation layer 40 in a certain direction.

[0082] The alignment film 30 exerts an alignment regulating force on the liquid crystal compound as described below. The alignment film may be a rubbed alignment film. The rubbed alignment film is imparted with an alignment regulating force by a rubbing treatment. The rubbed alignment film is obtained by applying an alignment film-forming composition onto the substrate 20 to form a coating film on the substrate 20, and then rubbing the coating film using a rubbing roll or the like. The alignment film 30 is more preferably a photo-aligned film. The photo-aligned film is imparted with an alignment regulating force by irradiating it with polarized light.

[0083] The material of the alignment film is not particularly limited as described above. The material of the alignment film may be a material used as a material of a rubbing alignment film or a material of a photo-alignment film. Examples of the material of the rubbing alignment film include polyvinyl alcohol resin, polyimide resin, polyamide resin, etc.

[0084] As the material of the photo-alignment film, a photo-alignment material that exhibits an alignment control force by irradiation with polarized light is more preferably used. The material of the photo-alignment film may be either a photodimerization type material or a photoisomerization type material. The photo-alignment film is obtained by applying the photo-alignment material onto the substrate 20 to form a coating film on the substrate 20, and curing the coating film by irradiating the coating film of the photo-alignment material with polarized light.

[0085] The thickness of the alignment film 30 along the third direction D3 may be 1 nm or more, or 60 nm or more. The thickness of the alignment film 30 may be 1000 nm or less, or 500 nm or less.

[0086] <Optical Properties of Retardation Layer 40> In the long retardation film 10 according to the present embodiment, the retardation layer 40 includes a first region 41, a pair of second regions 42, and a pair of third regions 43. The first region 41 is located between the pair of second regions 42 in the short side direction. The pair of second regions 42 are located between the pair of third regions 43 in the short side direction.

[0087] The first region 41 is cut out from the long retardation film 10 and used as a retardation film 10X (see FIG. 3). The first region 41 is given a desired retardation according to the application of the retardation film 10X. In the first region 41, the liquid crystal compound may be horizontally aligned. Horizontal alignment means that the liquid crystal compound is arranged along the sheet surface of the retardation layer 40. In the first region 41, the liquid crystal compound may be arranged to extend along one direction along a plane defined by the first direction D1 and the second direction D2. In this example, the first region 41 may have in-plane birefringence. The first region 41 may have a first slow axis A41 in the plane. The alignment of the liquid crystal compound in the first region 41 may be adjusted by an alignment restraining force applied to the alignment film 30.

[0088] The first orientation angle θ41 between the first slow axis A41 of the first region 41 and the longitudinal direction (second direction D2) may be, for example, 10° or more, 20° or more, or 30° or more. In this example, the first orientation angle θ41 may be 80° or less, 70° or less, or 60° or less.

[0089] As another example, the first orientation angle θ41 may be 100° or more, 110° or more, or 120° or more. In this other example, the first orientation angle θ41 may be 170° or less, 160° or less, or 150° or less.

[0090] In the example shown in FIG. 4, the first region 41 may be used as a λ / 4 retardation layer. The first region 41 of the retardation layer 40 may be laminated with a polarizing layer having a transmission axis in either the first direction D1 or the second direction D2 to form a circular polarizing plate. In this example, the first orientation angle θ41 between the first slow axis A41 of the first region 41 and the longitudinal direction (second direction D2) may be 35° or more, 40° or more, or 42° or more. In this example, the first orientation angle θ41 may be 55° or less, 50° or less, or 48° or less. In this example, the first orientation angle θ41 may be 45°.

[0091] In another example where the first region 41 is used as a λ / 4 retardation layer, the first orientation angle θ41 may be 125° or more, 130° or more, or 132° or more. In this other example, the first orientation angle θ41 may be 145° or less, 140° or less, or 138° or less. In this other example, the first orientation angle θ41 may be 135°.

[0092] As already explained, the orientation angle is the angle between the slow axis and the longitudinal direction (second direction D2). The orientation angle is the angle between the slow axis and the reference axis AS, which is an axis extending to one side in the longitudinal direction. The orientation angle is specified as an angle equal to or greater than 0° and less than 180°.

[0093] 4, in the second region 42, the orientation of the polymerizable liquid crystal compound contained in the cured product of the polymerizable liquid crystal composition is not regulated and is irregular. As one example, by forming the second region 42 on the alignment film 30 to which no alignment regulating force is applied, non-polarized light can be achieved in the second region 42. As another example, by forming the second region 42 on an optically isotropic substrate, for example, by forming the second region 42 on a substrate that is not stretched, non-aligned light can be achieved in the second region 42.

[0094] As shown in FIG. 4, the third region 43 has a third slow axis A43. In the third region 43, the liquid crystal compound may be horizontally aligned. As described above, horizontal alignment means that the liquid crystal compound is arranged along the sheet surface of the retardation layer 40. In the third region 43, the liquid crystal compound may be arranged to extend along one direction along the plane defined by the first direction D1 and the second direction D2. In this example, the third region 43 may have in-plane birefringence. The third region 43 may have a third slow axis A43 in the plane. The third orientation angle θ43 between the third slow axis A43 and the longitudinal direction (second direction D2) may be 40° or more, 50° or more, 60° or more, 70° or more, or 80° or more. The third orientation angle θ43 may be 140° or less, 130° or less, 120° or less, 110° or less, or 100° or less. The third orientation angle θ43 may be 90°.

[0095] The orientation of the liquid crystal compound in the third region 43 may be adjusted by an orientation restricting force imparted to the alignment film 30. The orientation of the liquid crystal compound in the third region 43 may be adjusted due to an orientation restricting force of the substrate 20 to which a slow axis has been imparted by stretching.

[0096] The retardation layer of the long retardation film can be transferred to a long transfer film and used. In the retardation layer of a conventional long retardation film, the liquid crystal compound was oriented in a fixed direction over the entire surface. When the retardation layer of a conventional long retardation film was transferred to a transfer film and the substrate was peeled off from the long retardation film in the longitudinal direction, burrs could be generated at the end of the retardation layer in the short direction (width direction). A retardation film with burrs attached thereto and a product such as an optical film manufactured using the retardation film cannot be used as a product. In addition, the generated burrs contaminate the manufacturing line in which the long retardation film is handled. If the manufacturing line is contaminated by burrs, burrs may also be attached to products manufactured on the manufacturing line thereafter. That is, the yield of products related to the long retardation film can be greatly reduced.

[0097] The inventors of the present disclosure have investigated the occurrence of burrs and found that the occurrence of burrs is affected by the relationship between the direction in which the substrate is peeled off from the long retardation film and the slow axis of the liquid crystal compound in the retardation layer.

[0098] First, as shown in FIG. 16, which will be referred to later, when the retardation layer is transferred to the transfer film, both end portions of the retardation layer are torn from the other portions and remain on the substrate. That is, only the center portion of the retardation layer is transferred to the transfer film. It was confirmed that when the retardation layer is torn, the retardation layer is easily torn along its slow axis. The orientation angle of the slow axis in the long retardation film is usually other than 0°, and is often 10° to 80° or 100° to 170°, for example, 45° or 135°. The retardation layer with an orientation angle of 45° or 135° was prone to burrs.

[0099] From this phenomenon, it is predicted that by reducing the orientation angle, the retardation layer can be stably torn along the longitudinal direction (second direction D2) which is the peeling direction of the base material. However, the orientation angle of the long retardation film is determined according to the use of the retardation film obtained from the long retardation film. It is also possible to give an orientation different from that of other regions only to the region where the retardation layer is torn, but this makes the manufacturing process complicated.

[0100] Based on such considerations, in this embodiment, the orientation of the liquid crystal compound in each of the regions 41, 42, and 43 of the retardation layer 40 is adjusted. In this embodiment, the second region 42 and the third region 43 are not intended to be cut out from the long retardation film 10 and used as the retardation film 10X. The second region 42 is a region intended to be torn in the retardation layer 40 when the substrate 20 is peeled off from the long retardation film 10. The third region 43 is a region intended to remain on the substrate 20 peeled off from the long retardation film 10.

[0101] First, in this embodiment, the retardation layer 40 is non-oriented in the second region 42. That is, there is no regularity in the arrangement of the liquid crystal compound. Therefore, in the second region 42, there is no direction in which the retardation layer 40 is likely to be torn. This allows the retardation layer 40 to be torn linearly in the second region 42 along the longitudinal direction (second direction D2) which is the peeling direction of the base material 20.

[0102] However, it was confirmed that the adhesion of the retardation layer was reduced in the non-oriented region. When the non-oriented region with reduced adhesion spread to the end of the retardation layer in the first direction D1, the retardation layer could not be torn stably. Specifically, when trying to tear the retardation layer, the retardation layer could not be torn linearly at the planned position. In addition, instead of tearing the retardation layer, the retardation layer was sometimes peeled off from the substrate in the entire area in the first direction D1. For example, when the retardation layer was transferred to the end area in the first direction D1 away from the substrate, burrs were generated due to cracks in the end area, as in the comparative example described later, and the manufacturing line was sometimes contaminated. When these phenomena occurred, the product could not be used as a product even if burrs were not generated due to poor tearing of the retardation layer.

[0103] On the other hand, in the present embodiment, the liquid crystal compound in the third region 43 of the retardation layer 40 is horizontally aligned. The third region 43 in which the liquid crystal compound is horizontally aligned has stronger adhesion to the substrate 20 than the non-aligned second region 42. Therefore, the adhesion of the third region 43 to adjacent layers is improved. This promotes tearing in the linear second region 42 along the peeling direction of the substrate 20 when the substrate 20 is peeled off from the long retardation film 10.

[0104] As a result, burrs generated at the end portion E40P in the short side direction (first direction D1) of the retardation layer 40P transferred to the transfer film 50 can be reduced.

[0105] From the viewpoint of reducing burrs generated at the end E40P of the transferred retardation layer 40P, it is effective to set the range of the third orientation angle θ43. When the slow axis A40 of the retardation layer 40 forms a large angle with respect to the direction in which the retardation layer 40 is torn, the retardation layer 40 has strong adhesion against tearing. From this point of view, the third orientation angle θ43 may be 40° or more and 140° or less. Furthermore, the third orientation angle θ43 may be 50° or more, 60° or more, 70° or more, or 80° or more. The third orientation angle θ43 may be 130° or less, 120° or less, 110° or less, or 100°. The third orientation angle θ43 may be 90°.

[0106] The first orientation angle θ41 with respect to the first slow axis A41 of the first region 41 is subject to restrictions according to the application of the long retardation film 10. The third orientation angle θ43 can be determined for the purpose of reducing the occurrence of burrs. It is effective to make the third orientation angle θ43 closer to 90° than the first orientation angle θ41. This can reduce burrs occurring at the end E40P in the short direction (first direction D1) of the retardation layer 40P transferred to the transfer film 50 when the first orientation angle θ41 is set to 10° or more and 80° or less, or 100° or more and 170° or less, or when the first orientation angle θ41 is set to 35° or more and 55° or less, or 125° or more and 145° or less.

[0107] As shown in FIG. 2 and FIG. 4, in the illustrated long retardation film 10, the first region 41 of the retardation layer 40 includes the center position in the short-side direction (first direction D1) of the long retardation film 10. The first region 41 of the retardation layer 40 includes the center position in the short-side direction (first direction D1) of the retardation layer 40. In addition, the third region 43 includes the end E40 of the retardation layer 40 in the short-side direction (first direction D1). Therefore, the area of ​​the first region 41 intended to be used as the retardation film 10X can be secured to be large. On the other hand, the area of ​​the third region 43 intended to remain on the substrate 20 can be reduced. As a result, the yield rate when manufacturing products from the long retardation film 10 can be sufficiently high.

[0108] In the illustrated example, the first region 41 and the second region 42 are adjacent to each other in the first direction D1. The second region 42 and the third region 43 are adjacent to each other in the first direction D1. Therefore, the yield rate when manufacturing products from the long retardation film 10 can be sufficiently high.

[0109] From the viewpoint of increasing the yield when manufacturing a product from a long retardation film and from the viewpoint of realizing stable transfer of the retardation layer 40, the dimensions of each of the regions 41, 42, 43 may be determined as follows. The length L42 (see FIG. 4) of the second region 42 along the short side direction (first direction D1) may be 1 mm or more, 5 mm or more, or 10 mm or more. The length L42 of the second region 42 along the short side direction (first direction D1) may be 200 mm or less, 100 mm or less, or 50 mm or less. The length L43 (see FIG. 4) of the third region 43 along the short side direction (first direction D1) may be 0.5 mm or more, 1 mm or more, or 1.5 mm or more. The length L43 of the third region 43 along the short side direction (first direction D1) may be 50 mm or less, 40 mm or less, or 30 mm or less. The length L41 (see FIG. 2) of the first region 41 along the short side direction (first direction D1) may be 6 times or more, 12 times or more, or 20 times or more than the length L42 (see FIG. 4) of the second region 42 along the short side direction (first direction D1). The length L41 (see FIG. 2) of the first region 41 along the short side direction (first direction D1) may be 250 times or less than the length L42 (see FIG. 4) of the second region 42 along the short side direction (first direction D1).

[0110] The illustrated long retardation film 10 includes an alignment film 30 located between the substrate 20 and the first region 41 and the second region 42 of the retardation layer 40. The first region 41 and the second region 42 are in contact with the alignment film 30. The alignment film 30 is not located between the third region 43 and the substrate 20 in the third direction D3. The third region 43 is in contact with the substrate 20. According to this example, the alignment of the liquid crystal compound in the first region 41 and the second region 42 can be adjusted by the alignment film 30. The alignment of the liquid crystal compound in the third region 43 can be adjusted by the substrate 20. For example, the alignment of the liquid crystal compound in the third region 43 can be controlled by the surface properties of the substrate 20, the substrate alignment angle θ20 with respect to the substrate slow axis A20 of the substrate 20, etc. That is, the alignment of the three regions 41, 42, and 43 of the retardation layer 40 can be controlled with a high degree of freedom.

[0111] In the illustrated example, the alignment film 30 includes a central region 31 and a pair of end regions 32 . The central region 31 faces the first region 41 of the retardation layer 40 in the third direction D3. The central region 31 includes the center of the long retardation film 10 in the short-side direction (first direction D1). The central region 31 includes the center of the alignment film 30 in the short-side direction (first direction D1). The central region 31 has an alignment regulating force. In the first region 41 of the retardation layer 40, the liquid crystal compound is aligned so as to extend along one direction corresponding to the alignment regulating force of the central region 31. Each end region 32 faces the second region 42 of the retardation layer 40 in the third direction D3. The end region 32 includes an end E30 in the short-side direction (first direction D1). The end region 32 does not have an alignment regulating force. In the second region 42 of the retardation layer 40, the liquid crystal compound is dispersed without regularity.

[0112] In this example, the alignment film 30 may be a photo-alignment film, which allows the alignment regulating force in each region of the alignment film 30 to be easily adjusted independently of other regions.

[0113] In this example, the substrate 20 may include a biaxially oriented polyethylene film. The substrate orientation angle θ20 with respect to the substrate slow axis A20 of the biaxially stretched polyethylene film is usually 40° or more and 140° or less. By forming the third region 43 of the retardation layer 40 on the biaxially stretched polyethylene film, the third orientation angle θ43 with respect to the third slow axis A43 of the third region 43 is 40° or more and 140° or less. That is, the third region 43 with extremely excellent adhesion to the substrate 20 can be easily formed.

[0114] The width W20 (see FIGS. 1 and 2) along the short side direction (first direction D1) of the substrate 20 may be 1000 mm or more, 1150 mm or more, or 1200 mm or more. The width W20 along the short side direction (first direction D1) of the substrate 20 may be 2000 mm or less, 1800 mm or less, or 1600 mm or less. The width W30 (see FIGS. 1 and 2) along the short side direction (first direction D1) of the alignment film 30 may be 950 mm or more, 1100 mm or more, or 1150 mm or more. The width W30 along the short side direction (first direction D1) of the alignment film 30 may be 1950 mm or less, 1750 mm or less, or 1550 mm or less. The width W40 (see FIG. 1 and FIG. 2) of the retardation layer 40 along the short side direction (first direction D1) may be 970 mm or more, 1120 mm or more, or 1170 mm or more. The width W40 of the retardation layer 40 along the short side direction (first direction D1) may be 1970 mm or less, 1770 mm or less, or 1570 mm or less. The width W40 of the retardation layer 40 along the short side direction (first direction D1) may be larger than the width W30 of the alignment film 30 along the short side direction (first direction D1). The length of the long retardation film 10 along the longitudinal direction (second direction D2) may be 5 m or more, 10 m or more, or 100 m or more. The length of the long retardation film 10 along the longitudinal direction (second direction D2) may be 10,000 m or less, 8,000 m or less, or 6,000 m or less.

[0115] <Method of Manufacturing Long Retardation Film 10> Next, a description will be given of an example of a method for producing the long retardation film 10. In the following description, the long retardation film 10 shown in Figs. 1 to 4 is produced by a roll-to-roll production method.

[0116] 5 shows an example of a manufacturing method of the long retardation film 10 and an example of a manufacturing apparatus 70 for the long retardation film 10. The manufacturing apparatus 70 includes a supply core 71 on which the long substrate 20 is wound, a recovery core 72 for recovering the manufactured long retardation film 10, and a transport roll 73 for guiding the substrate 20 and the long retardation film 10 from the supply core 71 to the recovery core 72. The manufacturing apparatus 70 includes a first supply device 76, a first drying device 77, and a first curing device 78 as devices for forming the alignment film 30 on the substrate 20. The manufacturing apparatus 70 includes a second supply device 81, a second drying device 82, and a second curing device 83 as devices for forming the retardation layer 40.

[0117] First, the substrate 20 wound around a supply core 71 is supplied. The substrate 20 transported by a transport roll 73 passes a position facing a first supply device 76. The first supply device 76 applies a composition 34 for forming an alignment film, which contains a photo-alignable material, to one surface of the substrate 20. As shown in FIG. 6, a first coating film 35 of the composition 34 for forming an alignment film is formed on one surface of the substrate 20.

[0118] The substrate 20 transported by the transport roll 73 passes through a position facing a first drying device 77. The first drying device 77 dries the first coating film 35 of the composition 34 for forming an alignment film. As an example, the first drying device 77 supplies a high-temperature and dry gas to the first coating film 35 of the composition 34 for forming an alignment film.

[0119] The substrate 20 transported by the transport roll 73 passes through a position facing the first curing device 78. The first curing device 78 has a configuration corresponding to the curing process of the first coating film 35 of the composition for forming an alignment film 34. As shown in FIG. 7, the first curing device 78 may include a first exposure device 78A and a mask 78B. In the illustrated example, the first exposure device 78A emits polarized light toward the first coating film 35 of the composition for forming an alignment film 34. The mask 78B includes a transmission region 78B1 and a light-shielding region 78B2. The polarized light emitted from the first exposure device 78A is transmitted through the transmission region 78B1. The polarized light emitted from the first exposure device 78A is shielded by the light-shielding region 78B2.

[0120] As shown in FIG. 7, the first coating film 35 of the composition 34 for forming an alignment film is irradiated with polarized light in a region facing the transmission region 78B1. By exposure to polarized light, the first coating film 35 is given an alignment regulating force according to the polarization. The exposed region of the first coating film 35 becomes the central region 31 of the alignment film 30. The first coating film 35 of the composition 34 for forming an alignment film is not irradiated with polarized light in a region facing the light-shielding region 78B2. The unexposed region of the first coating film 35 becomes the edge region 32 of the alignment film 30. The edge region 32 does not have an alignment regulating force.

[0121] 8, an intermediate 15 including the substrate 20 and the alignment film 30 is obtained. In the intermediate 15, the alignment film 30 includes a central region 31 and edge regions 32. The alignment film 30 has an alignment regulating force only in the central region 31.

[0122] Hatching is applied in Fig. 8, Fig. 9 to Fig. 11, Fig. 14, Fig. 16, and Fig. 19 to Fig. 21, which will be described later, according to the alignment regulating force of the alignment film 30 and the alignment state of the retardation layer 40. The hatching applied in Fig. 8 to Fig. 11, Fig. 14, Fig. 16, and Fig. 19 to Fig. 21 does not show a cross section. In Fig. 8 to Fig. 11, Fig. 14, Fig. 16, and Fig. 19 to Fig. 21, no pattern is applied to the region where the alignment regulating force of the alignment film 30 is not generated and the region where the liquid crystal compound in the retardation layer 40 does not have a regular alignment.

[0123] As shown in Fig. 5, the intermediate 15 is transported by transport rolls 73 and passes a position facing a second supplying device 81. The second supplying device 81 applies a liquid crystal composition 44 containing a liquid crystal compound onto one surface of the intermediate 15. As shown in Fig. 9, a second coating film 45 is formed on one surface of the substrate 20 and on the alignment film 30. The second coating film 45 is not cured, and the alignment of the liquid crystal compound in the second coating film 45 can be changed.

[0124] In the region of the second coating film 45 facing the central region 31 of the alignment film 30 in the third direction D3, the liquid crystal compound is aligned so as to extend in a certain direction by the alignment restricting force of the central region 31. A first region 41 of the retardation layer 40 is formed in a region of the second coating film 45 facing the central region 31 of the alignment film 30 in the third direction D3. In the manufacture of the long retardation film 10 shown in FIG. 4, the liquid crystal compound in the first region 41 is aligned so that the first orientation angle θ41 is 45°.

[0125] The edge region 32 of the alignment film 30 does not have an alignment restricting force. In the region of the second coating film 45 facing the edge region 32 of the alignment film 30 in the third direction D3, the alignment of the liquid crystal compound is not restricted by the alignment film 30. In the region facing the edge region 32, the alignment of the liquid crystal compound does not have regularity. The second region 42 of the retardation layer 40 is formed in the region of the second coating film 45 facing the edge region 32 of the alignment film 30 in the third direction D3. In the production of the long retardation film 10 shown in FIG. 4, the second region 42 is non-oriented.

[0126] As shown in FIG. 9, the second coating film 45 extends to the outside of the alignment film 30 in the short-side direction (first direction D1). The "outside" in the short-side direction means the opposite side to the center in the short-side direction. The "inside" in the short-side direction means the center side in the short-side direction. The end region of the second coating film 45 in the short-side direction (first direction D1) faces the substrate 20 in the third direction D3. The end region of the second coating film 45 in the short-side direction (first direction D1) is located on the substrate 20. In the end region of the second coating film 45 in the short-side direction (first direction D1), the liquid crystal compound receives an alignment regulating force from the substrate 20. A resin substrate usually exerts an alignment regulating force in the direction with the highest stretch ratio. A stretched resin substrate usually exerts an alignment regulating force in the direction parallel to its slow axis. A stretched polyester substrate exerts an alignment regulating force in the direction parallel to its slow axis. A third region 43 of the retardation layer 40 is formed in a region of the second coating film 45 that contacts the substrate 20 in the third direction D3. In the production of the long retardation film 10 shown in FIG. 4, the liquid crystal compound in the third region 43 may be aligned so that the third orientation angle θ43 is 40° or more and 140° or less.

[0127] The intermediate 15 transported by the transport roll 73 passes a position facing the second drying device 82. The second drying device 82 dries the second coating film 45 of the liquid crystal composition 44. As an example, the second drying device 82 supplies a high-temperature and dry gas to the second coating film 45 of the liquid crystal composition 44.

[0128] The intermediate 15 transported by the transport roll 73 passes through a position facing the second curing device 83. The second curing device 83 has a configuration corresponding to the curing process of the second coating film 45 of the liquid crystal composition 44. As shown in FIG. 10, the second curing device 83 may include an exposure device 83A. In the illustrated example, the exposure device 83A emits ionizing radiation toward the second coating film 45 of the liquid crystal composition 44. The second coating film 45 of the liquid crystal composition 44 is irradiated with ionizing radiation from the second curing device 83 and cured. During the curing process, the second coating film 45 is cured while the liquid crystal compound maintains its alignment. In the first region 41 and the third region 43 of the retardation layer 40, the liquid crystal compound is horizontally aligned. In the second region 42, the liquid crystal compound is irregularly aligned.

[0129] In this manner, the long retardation film 10 is manufactured. The manufactured long retardation film 10 includes a longitudinal direction and a transverse direction. The long retardation film 10 includes a substrate 20, an alignment film 30, and a retardation layer 40. Each of the substrate 20, the alignment film 30, and the retardation layer 40 includes a longitudinal direction parallel to the long direction of the long retardation film 10. Each of the substrate 20, the alignment film 30, and the retardation layer 40 includes a transverse direction parallel to the transverse direction of the long retardation film 10.

[0130] <<Long Optical Film 55 and Long Polarizing Film 60>> A long optical film 55 is manufactured using the long retardation film 10 described above. The long optical film 55 includes a long transferred film 50 and a long retardation layer 40P transferred from the long retardation film 10. Fig. 11 is a cross-sectional view showing an example of the long optical film 55. The long optical film 55 shown in Fig. 11 is produced by transferring the retardation layer 40P of the long retardation film 10 shown in Figs. 1 to 10 to the transferred film 50 shown in Fig. 12.

[0131] The transfer film 50 shown in Fig. 12 includes a long polarizing layer 52. The polarizing layer 52 transmits a polarized component that vibrates in a specific direction and blocks a polarized component that vibrates in a direction perpendicular to the specific direction. The long optical film 55 shown in Fig. 11 functions as a circular polarizer by combining the polarizing layer 52 and the first region 41 of the retardation layer 40P that functions as a λ / 4 retardation layer. That is, in this example, the long optical film 55 becomes a long polarizing film 60.

[0132] Strictly speaking, the long polarizing film 60 functions as a circular polarizing plate for light of a certain wavelength, and normally functions as an elliptical polarizing plate for light of other wavelengths. A polarizing plate that functions as a circular polarizing plate for light of a wavelength of 400 nm or more and 800 nm or less is called a circular polarizing plate.

[0133] The transfer film 50 and the long optical film 55 will be described in further detail with reference to the specific examples shown in FIG. 12 and FIG.

[0134] The transferred film 50 and the long optical film 55 are long and have a longitudinal direction and a transverse direction. Each layer that is a component of the transferred film 50 and the long optical film 55 is also long and has a longitudinal direction and a transverse direction. The longitudinal direction of the transferred film 50 is parallel to the longitudinal direction of the components of the transferred film 50. The transverse direction of the transferred film 50 is parallel to the transverse direction of the components of the transferred film 50. The longitudinal direction of the long optical film 55 is parallel to the longitudinal direction of the components of the long optical film 55. The transverse direction of the long optical film 55 is parallel to the transverse direction of the components of the long optical film 55.

[0135] The transfer film 50 includes a substrate 51 and a bonding layer 53. The transfer film 50 shown in FIG. 12 includes a substrate 51, a polarizing layer 52, and a bonding layer 53 in this order in the third direction D3. The substrate 51 of the transfer film 50 is not particularly limited. The substrate 51 of the transfer film 50 may be the same as the substrate 20 of the long retardation film 10 described above. From the viewpoint of being able to apply a roll-to-roll manufacturing method, the material of the substrate 51 may be a resin. Examples of the material of the substrate 51 include a polyester film, a polycarbonate film, a cycloolefin polymer film, a triacetyl cellulose film, and an acrylic film. The thickness of the substrate 51 along the third direction D3 can be set to the same range as the thickness of the substrate 20 of the long retardation film 10 along the third direction D3.

[0136] The bonding layer 53 is not particularly limited. The bonding layer 53 may include an adhesive material or an adhesive material. The material of the bonding layer 53 is not particularly limited. The material of the bonding layer 53 may be a PVA adhesive material or an acrylic adhesive material. The thickness of the bonding layer 53 along the third direction D3 may be 1 μm or more, 1.5 μm or more, or 2 μm or more. The thickness of the bonding layer 53 may be 200 μm or less, 160 μm or less, or 120 μm or less.

[0137] The polarizing layer 52 may include an absorptive polarizer. The absorptive polarizer has an absorption axis and a transmission axis. The absorptive polarizer transmits a linearly polarized component that vibrates in a direction parallel to the transmission axis, and absorbs a linearly polarized component that vibrates in a direction parallel to the absorption axis. The polarizing layer 52 may include a reflective polarizer. The reflective polarizer has a reflection axis and a transmission axis. The reflective polarizer transmits a linearly polarized component that vibrates in a direction parallel to the transmission axis, and reflects a linearly polarized component that vibrates in a direction parallel to the reflection axis.

[0138] The polarizer of the polarizing layer 52 may be a polyvinyl alcohol film, a polyvinyl formal film, a polyvinyl acetal film, or an ethylene-vinyl acetate copolymer-based saponified film dyed with iodine or the like and stretched. The polarizer of the polarizing layer 52 may be a coating type polarizer coated with a dichroic guest-host material. The polarizer of the polarizing layer 52 may be a multilayer thin film type polarizer. The thickness of the polarizing layer 52 along the third direction D3 may be 0.5 μm or more, 1 μm or more, or 2 μm or more. The thickness of the polarizing layer 52 may be 150 μm or less, 120 μm or less, or 80 μm or less.

[0139] An end E53 in the short-side direction (first direction D1) of the bonding layer 53 may face the second region 42 of the retardation layer 40 included in the long retardation film 10. This allows the retardation layer 40 to be torn in the second region 42 when the retardation layer 40 is transferred. The second region 42 is non-oriented. When the retardation layer 40 is torn in the second region 42, the influence of the retardation layer on the tearing direction can be reduced.

[0140] Since the end E53 of the bonding layer 53 faces the second region 42, the width of each layer along the short side direction (first direction D1) may be set as follows. The width W53 (see FIG. 12) along the short side direction (first direction D1) of the bonding layer 53 may be smaller than the width W40 along the short side direction (first direction D1) of the retardation layer 40 included in the long retardation film 10. The width W53 (see FIG. 12) along the short side direction (first direction D1) of the bonding layer 53 may be smaller than the total lengths L42, L41, L42 along the short side direction (first direction D1) of the first region 41 and the pair of second regions 42 of the retardation layer 40 included in the long retardation film 10. The width W53 (see FIG. 12) of the bonding layer 53 along the short side direction (first direction D1) may be larger than the length L41 of the first region 41 of the retardation layer 40 included in the long retardation film 10 along the short side direction (first direction D1).

[0141] The width W53 of the bonding layer 53 along the short side direction (first direction D1) may be 940 mm or more, 1090 mm or more, or 1140 mm or more. The width W53 of the bonding layer 53 along the short side direction (first direction D1) may be 1940 mm or less, 1740 mm or less, or 1540 mm or less.

[0142] A width W51 (see FIG. 12) along the short side direction (first direction D1) of the base material 51 may be larger than a width W53 along the short side direction (first direction D1) of the bonding layer 53. The width W51 along the short side direction (first direction D1) of the base material 51 may be set to be in the same range as the width W20 along the short side direction (first direction D1) of the base material 20.

[0143] The width W52 of the polarizing layer 52 along the short side direction (first direction D1) may be equal to or larger than the width W53 of the bonding layer 53 along the short side direction (first direction D1). The width W52 of the polarizing layer 52 along the short side direction (first direction D1) may be equal to or smaller than the width W51 of the base material 51 along the short side direction (first direction D1). By setting the width of the polarizing layer 52 in this manner, it is possible to suppress the variation in the thickness of the transferred film 50 in the region where the bonding layer 53 is provided. This allows the retardation layer 40P of the long retardation film 10 to be stably transferred to the transferred film 50.

[0144] The length of the transferred film 50 along the longitudinal direction (second direction D2) may be set to be in the same range as the length of the long retardation film 10 along the longitudinal direction (second direction D2).

[0145] As shown in FIG. 11, the long optical film 55 includes a transfer film 50 and a retardation layer 40P. The retardation layer 40P is a part of the retardation layer 40 included in the long retardation film 10. The retardation layer 40P of the long optical film 55 includes the first region 41 of the retardation layer 40 included in the long retardation film 10 and a part (first portion) 42A of each of the pair of second regions 42. The retardation layer 40P of the long optical film 55 does not include the remaining part (second portion) 42B other than the part 42A of each of the pair of second regions 42 of the retardation layer 40 included in the long retardation film 10 and the pair of third regions 43. As shown in FIG. 16 to be referred to later, the inner part in the short direction (first direction D1) of each second region 42 of the retardation layer 40 is transferred to the transfer film 50. The outer portions of each of the second regions 42 of the retardation layer 40 in the short-side direction (first direction D1) remain on the substrate 20 together with the third regions 43.

[0146] In the example shown in FIG. 11, the transfer film 50 includes a substrate 51, a polarizing layer 52, a bonding layer 53, a retardation layer 40P, and an alignment film 30P in this order in the third direction D3. The alignment film 30P is a part of the alignment film 30 included in the long retardation film 10. The alignment film 30P is a part of the alignment film 30 included in the long retardation film 10 that faces the retardation layer 40P in the third direction D3. The alignment film 30P of the transfer film 50 includes the central region 31 of the alignment film 30 included in the long retardation film 10 and a part (first part) 32A of each of a pair of end regions 32. The alignment film 30P of the transfer film 50 does not include a remaining part (second part) 32B other than the part 32A of each of a pair of end regions 32 of the alignment film 30 included in the long retardation film 10. An inner portion in the short side direction (first direction D1) of each end region 32 of the alignment film 30 is transferred to the transfer film 50. An outer portion in the short side direction (first direction D1) of each end region 32 of the alignment film 30 remains on the substrate 20.

[0147] The long optical film 55 shown in FIG. 12 functions as a long polarizing film 60. In this application, the retardation layer 40P functions as a λ / 4 retardation layer. The angle between the first slow axis A41 in the first region 41 of the retardation layer 40P and the transmission axis of the polarizing layer 52 may be 35° or more, 40° or more, or 42° or more. The angle between the first slow axis A41 of the retardation layer 40P and the transmission axis of the polarizing layer 52 may be 55° or less, 50° or less, or 48° or less. The angle between the first slow axis A41 of the retardation layer 40P and the transmission axis of the polarizing layer 52 may be 45°.

[0148] A description will be given of an example of a method for producing the long optical film 55. In the following description, a long polarizing film 60 shown in Fig. 11 is produced as an example of the long optical film 55 by a roll-to-roll production method.

[0149] FIG. 13 shows an example of a method for manufacturing the long optical film 55 and an example of a manufacturing apparatus 90 for the long optical film 55. The manufacturing apparatus 90 includes a first supply core 91, a second supply core 92, a first recovery core 93, a second recovery core 94, and a transport roll 95. The first supply core 91 unwinds the long retardation film 10. The long retardation film 10 may be manufactured in advance and wound around the first supply core 91. Instead of the illustrated example, the long retardation film 10 may be continuously manufactured and sent out to the transport roll 95. The second supply core 92 unwinds the long transfer film 50. The long transfer film 50 may be manufactured in advance and wound around the second supply core 92. Instead of the illustrated example, the long transfer film 50 may be continuously manufactured and sent out to the transport roll 95. The first recovery core 93 recovers the manufactured long optical film 55. The second recovery core 94 recovers the elongated substrate 20 . The transport rolls 95 include a first transport roll 95A and a second transport roll 95B.

[0150] First, the long retardation film 10 is supplied from the first supply core 91 toward the first transport roll 95A. In parallel with the supply of the long retardation film 10, the transfer film 50 is supplied from the second supply core 92 toward the first transport roll 95A. As shown in FIG. 14, the long retardation film 10 and the transfer film 50 are supplied between a pair of first transport rolls 95A. Between the pair of first transport rolls 95A, the long retardation film 10 and the transfer film 50 are laminated. The retardation layer 40 of the long retardation film 10 and the bonding layer 53 of the transfer film 50 are in contact with each other. The pair of first transport rolls 95A push the long retardation film 10 and the transfer film 50 toward each other. As a result, the retardation layer 40 is bonded to the bonding layer 53.

[0151] As shown in FIG. 14, both ends E53 of the bonding layer 53 face the second region 42 of the retardation layer 40 in the third direction D3. That is, the bonding layer 53 bonds to the first region 41 of the retardation layer 40 and the part 42A which is the inner part in the first direction D1 of the pair of second regions 42. The bonding layer 53 does not face the pair of third regions 43 of the retardation layer 40 and the remaining part 42B other than the part 42A which is the outer part in the first direction D1 of the pair of second regions 42 in the third direction D3. In a state where the long retardation film 10 is laminated on the transfer film 50, the third region 43 and the remaining part 42B of the second region 42 are located outside the bonding layer 53 in the short direction (first direction D1).

[0152] Next, as shown in Fig. 13, the laminated long retardation film 10 and the transferred film 50 are supplied toward a gap between the second transport rolls 95B. As shown in Fig. 13 and Fig. 15, after the long retardation film 10 passes between the pair of second transport rolls 95B, the substrate 20 is peeled off from the long retardation film 10. In the roll-to-roll manufacturing method, the substrate 20 is peeled off along the second direction D2, which is the longitudinal direction.

[0153] As shown in FIG. 16, the portion of the retardation layer 40 that was bonded to the bonding layer 53 is maintained as bonded to the bonding layer 53 as the retardation layer 40P and is transferred to the transfer film 50. The portion of the alignment film 30 that faces the retardation layer 40P in the third direction D3 is also transferred to the transfer film 50 as the alignment film 30P. As shown in FIG. 16, the retardation layer 40 is torn at a position in the second region 42 that faces the end E53 of the bonding layer 53 in the third direction D3. Similarly, the alignment film 30 is torn at a position in the end region 32 that faces the end E53 of the bonding layer 53 in the third direction D3.

[0154] That is, the first region 41 of the retardation layer 40 and a part 42A that is an inner part of the second region 42 in the first direction D1 are transferred to the transfer film 50 as the retardation layer 40P. The third region 43 of the retardation layer 40 and a remaining part 42B that is an outer part of the second region 42 in the first direction D1 remain in close contact with the substrate 20. The central region 31 of the alignment film 30 and a part 32A that is an inner part of the end region 32 in the first direction D1 are transferred to the transfer film 50 as the alignment film 30P. The remaining part 32B that is an outer part of the end region 32 in the first direction D1 of the alignment film 30 remains bonded to the substrate 20.

[0155] In this manner, the retardation layer 40P and the alignment film 30P are transferred from the long retardation film 10 to the transfer film 50, thereby continuously producing a long polarizing film 60. The produced long polarizing film 60 is collected in a first collecting core 93. The base material 20 peeled off from the alignment film 30P and the retardation layer 40P is collected in a second collecting core 94.

[0156] According to this embodiment, the second region 42 of the retardation layer 40 to be torn during transfer is non-oriented. In the second region 42, the liquid crystal compound is irregularly arranged. Therefore, the direction in which the retardation layer 40 is torn in the second region 42 is not easily affected by the orientation of the liquid crystal compound contained in the retardation layer 40. The retardation layer 40 can be torn in the second region 42 approximately along the longitudinal direction (second direction D2) in which the base material 20 is peeled off. In addition, in this embodiment, the liquid crystal compound in the third region 43 of the retardation layer 40 is horizontally oriented. Therefore, when the retardation layer 40 is torn in the longitudinal direction (second direction D2), the third region 43 can stably maintain adhesion to the base material 20. For these reasons, the retardation layer 40 is torn smoothly in the second region 42. As a result, it is possible to effectively suppress the occurrence of burrs at the end E40P in the short-side direction (first direction D1) of the retardation layer 40P.

[0157] In the illustrated example, the edge region 32 of the alignment film 30 is not provided with an alignment regulating force. That is, the edge region 32 does not have a directional configuration. Therefore, the alignment film 30 is torn in the edge region 32 smoothly along the peeling direction of the substrate 20. This also helps to prevent the generation of burrs.

[0158] In the above-mentioned specific example, the third region 43 has a third slow axis A43. The third orientation angle θ43 between the third slow axis A43 and the longitudinal direction may be 40° or more and 140° or less. According to such an example, the retardation layer 40 exhibits strong adhesion to the adjacent layers in the third region 43. Therefore, the retardation layer 40 is stably torn in the second region 42, and the occurrence of burrs in the end portion E40P in the short side direction (first direction D1) of the retardation layer 40P can be effectively suppressed.

[0159] From the viewpoint of reducing burrs generated at the end E40P of the transferred retardation layer 40P, the third orientation angle θ43 may be 40° or more, 50° or more, 60° or more, 70° or more, or 80° or more. The third orientation angle θ43 may be 140° or less, 130° or less, 120° or less, 110° or less, or 100° or less. The third orientation angle θ43 may be 90°.

[0160] From the viewpoint of increasing the yield of the optical film 55X and the polarizing film 60X and from the viewpoint of realizing stable transfer of the retardation layer 40, the length L42A (see FIG. 11) of the second region (part) 42A included in the retardation layer 40P along the short-side direction (first direction D1) may be determined as follows. The length L42A may be 1 mm or more, 2 mm or more, or 5 mm or more. The length L42A may be 100 mm or less, 50 mm or less, or 25 mm or less. From the same viewpoint, the length L32A (see FIG. 11) of the end region 32 (i.e., the part 32A) included in the alignment film 30P along the short-side direction (first direction D1) may be determined as follows. The length L32A may be 1 mm or more, 2 mm or more, or 5 mm or more. The length L32A may be 100 mm or less, 50 mm or less, or 25 mm or less. The length L41 along the short-side direction (first direction D1) of the first region 41 included in the retardation layer 40P may be 12 times or more, 24 times or more, or 40 times or more of the length L42A along the short-side direction (first direction D1) of the second region (part) 42A included in the retardation layer 40P. The length L41 may be 500 times or less of the length L42A.

[0161] The transfer film 50, the long optical film 55, and the long polarizing film 60 can be handled as the winding bodies 50R, 55R, and 60R wound around the winding core 12 with the winding axis RA as the center, as shown in FIG. 3, in the same manner as the above-mentioned long retardation film 10. This makes it easier to handle the long films 50, 55, and 60. The long films 50, 55, and 60 can be manufactured by a roll-to-roll manufacturing method. The long films 50, 55, and 60 are excellent in production efficiency and manufacturing cost. By cutting the long optical film 55 and the long polarizing film 60 to a desired size, individual optical films 55X and individual polarizing films 60X can be obtained. According to this example, the optical film 55X and the polarizing film 60X having various dimensions can be obtained from the long optical film 55 and the long polarizing film 60 according to needs. The optical film 55X and the polarizing film 60X having various dimensions can be provided in a timely manner.

[0162] The optical film 55X and the polarizing film 60X obtained from the long optical film 55 and the long polarizing film 60 may be applied to the display device 100. In the example shown in Fig. 17, the optical film 55X and the polarizing film 60X are arranged to be overlapped on a display element 101 serving as an image forming device. In this example, the optical film 55X and the polarizing film 60X have a reflection suppressing function that suppresses reflection of external light such as ambient light on the surface of the display device 100. The reflection suppressing function can improve the contrast of an image displayed by the display device 100.

[0163] Examples of the display element 101 include a liquid crystal display element, an organic EL display element, an inorganic EL display element, a plasma display element, an electronic paper display element, an LED display element (such as a micro LED), and a quantum dot. These display elements may have a touch panel function inside the display element.

[0164] In the specific example shown in FIG. 18, the display device 100 constitutes an organic EL display device. The display device 100 includes an organic EL display panel 103 and an optical film 55X (polarizing film 60X). The optical film 55X (polarizing film 60X) is overlaid on the image display surface of the organic EL display panel 103 and exhibits a reflection suppressing function. In this example, the optical film 55X includes a retardation layer 40P that functions as a λ / 4 retardation layer and a polarizing layer 52 that functions as a polarizer. The retardation layer 40P is located between the polarizing layer 52 and the organic EL display panel 103. EXAMPLES

[0165] The present disclosure will be described in more detail with reference to examples, but the present disclosure is not limited to the following examples.

[0166] <Long retardation film> As will be described below, the long retardation films according to Example 1, Comparative Example 1, and Comparative Example 2 were produced by a roll-to-roll process.

[0167] Example 1 By the manufacturing method described above with reference to FIGS. 5 to 10, the long retardation film shown in FIGS. 1 to 4 was manufactured by a roll-to-roll system.

[0168] The substrate was a PET film "Cosmoshine A4160 (thickness 100 μm, PET film (A))" manufactured by Toyobo Co., Ltd. The substrate was a biaxially stretched film and had in-plane birefringence. The stretch ratio in the short direction in the biaxial stretching was larger than the stretch ratio in the long direction.

[0169] A composition for forming an alignment film was applied to the untreated surface (non-primer surface) of the substrate to form a first coating film having a thickness of 300 nm. The composition for forming an alignment film contained a polycinnamate compound and a propylene glycol monomethyl ether solution (solid content 4.5%). The first coating film was dried by being held in an atmosphere of 100°C for 1 minute. The first coating film was exposed to polarized light to produce an alignment film. The polarized light exposure conditions were an irradiation wavelength of 310 nm and an irradiation dose of 20 mJ / cm2. 2 In this manner, an intermediate including the substrate and the alignment film was obtained.

[0170] As described with reference to FIG. 7, the first coating film was partially exposed using a mask. Only the central region of the first coating film was exposed to polarized light. The edge regions of the first coating film were not exposed to polarized light. The central region of the obtained alignment film was imparted with an alignment regulating force that resulted in an alignment angle of 45°. The edge regions of the obtained alignment film were not imparted with an alignment regulating force.

[0171] A polymerizable liquid crystal compound was synthesized with reference to the synthesis of compound 4 in Example 4 of JP5962760B. This polymerizable liquid crystal compound showed reverse wavelength dispersion. A polymerizable liquid crystal composition was prepared by adding 4 parts by mass of Irgacure 907 as an initiator and 0.3 parts by mass of Megafac F-477 manufactured by DIC Corporation as a surfactant to 100 parts by mass of the polymerizable liquid crystal compound. The polymerizable liquid crystal composition further contained toluene so that the solid content was 20%. A second coating film was formed by applying the polymerizable liquid crystal composition to the surface of the intermediate on which the alignment film was formed.

[0172] Next, the second coating film was dried by being held in an atmosphere of 120° C. for 1 minute. Thereafter, the second coating film was dried using a Fusion-UV device manufactured by Heraeus GmbH with an irradiation dose of 300 mJ / cm 2 2 The second coating film was irradiated with ultraviolet light in order to cure the second coating film 45 and form the retardation layer 40. In this manner, a long retardation film including the substrate, the alignment film, and the retardation layer was obtained.

[0173] As shown in FIG. 19, the retardation layer 40 included in the long retardation film 10 of Example 1 included a first region 41 facing the central region 31 of the alignment film 30 in the third direction D3, a pair of second regions 42 facing the end region 32 of the alignment film 30 in the third direction D3, and a pair of third regions 43 located on both sides of the alignment film 30 in the first direction D1 and facing the substrate 20 in the third direction D3. In the first region 41, the polymerizable liquid crystal compound was horizontally aligned at an orientation angle of 45°. In the second region 42, the polymerizable liquid crystal compound was non-aligned. In the third region 43, the polymerizable liquid crystal compound was horizontally aligned. The third orientation angle of the polymerizable liquid crystal compound in one of the pair of third regions 43 spaced apart in the first direction D1 was 60°. The third orientation angle of the polymerizable liquid crystal compound in the other third region 43 was 87°. The in-plane retardation Re in the first region was 140 nm. As described above, the in-plane retardation Re was measured using the product name "RETS-100" manufactured by Otsuka Electronics Co., Ltd.

[0174] The width L41 of the first region 41 in the short side direction (first direction D1) perpendicular to the longitudinal direction was 1250 mm. The width L42 of each second region 42 in the short side direction (first direction D1) perpendicular to the longitudinal direction was 30 mm. The width L43 of each third region 43 in the short side direction (first direction D1) perpendicular to the longitudinal direction was 5 mm.

[0175] Comparative Example 1 The manufacturing method of the long retardation film of Comparative Example 1 was different from the manufacturing method of the long retardation film of Example 1 only in that the entire region of the first coating film was exposed to polarized light. Therefore, in Comparative Example 1, the alignment film was given an alignment regulating force with an alignment angle of 45° in the entire region. In Comparative Example 1, the polymerizable liquid crystal compound was horizontally aligned at an alignment angle of 45° in the entire region of the retardation layer facing the alignment film.

[0176] As shown in FIG. 20, the retardation layer 140 included in the long retardation film 110 of Comparative Example 1 included a first region 141 facing the alignment film 130 in the third direction D3, and a pair of third regions 143 located on both sides of the alignment film 130 in the first direction D1 and facing the substrate 120 in the third direction D3. In the first region 141, the polymerizable liquid crystal compound was horizontally aligned at an orientation angle of 45°. In the third region 143, the polymerizable liquid crystal compound was horizontally aligned. The third orientation angle of the polymerizable liquid crystal compound in one of the pair of third regions 143 spaced apart in the first direction D1 was 60°. The third orientation angle of the polymerizable liquid crystal compound in the other third region 143 was 87°. The in-plane retardation Re in the first region was 140 nm. As described above, the in-plane retardation Re was measured using a product name "RETS-100" manufactured by Otsuka Electronics Co., Ltd.

[0177] The width L141 in the short side direction (first direction D1) perpendicular to the longitudinal direction of the first region 141 was 1310 mm. The width L143 in the short side direction (first direction D1) perpendicular to the longitudinal direction of each third region 143 was 5 mm. The retardation layer of the long retardation film according to Comparative Example 1 had a configuration in which the configuration of the first region 41 was applied to the region of the second region 42 of the retardation layer of the long retardation film according to Example 1.

[0178] Comparative Example 2 In Comparative Example 2, an intermediate including a substrate and an alignment film was produced in the same manner as in Example 1. The alignment film of the obtained intermediate included a central region having an alignment regulating force with an alignment angle of 45° and an end region having no alignment regulating force. However, in Comparative Example 2, the length of the end region of the alignment film in the first direction D1 was made longer than that in Example 1. A retardation layer was produced on the intermediate. The retardation layer was produced by the same production method as in Example 1. However, in Comparative Example 2, the width of the retardation layer along the second direction was made shorter than the width of the alignment film along the second direction. The retardation layer was located only in the region facing the alignment film in the third direction D3.

[0179] As shown in FIG. 21, in the long retardation film 210 of Comparative Example 2, the retardation layer 240 included a first region 241 facing the central region 231 of the alignment film 230 in the third direction D3, and a second region 242 facing the end region 232 of the alignment film 230 in the third direction D3. In the first region 241, the polymerizable liquid crystal compound was horizontally aligned at an alignment angle of 45°. In the second region 242, the polymerizable liquid crystal compound was unaligned. The in-plane retardation Re in the first region was 140 nm. As described above, the in-plane retardation Re was measured using a product name "RETS-100" manufactured by Otsuka Electronics Co., Ltd.

[0180] The width L241 in the short side direction (first direction D1) perpendicular to the longitudinal direction of the first region 241 was 1250 mm. The width L242 in the short side direction (first direction D1) perpendicular to the longitudinal direction of each second region 242 was 30 mm. The retardation layer of the long retardation film according to Comparative Example 2 had a configuration in which the configuration of the second region 42 was applied to the region of the third region 43 of the retardation layer of the long retardation film according to Example 1.

[0181] <Evaluation> 13 to 16, the long retardation films of Example 1, Comparative Example 1, and Comparative Example 2 were laminated on a long film to be transferred including a bonding layer, and then the substrate was peeled off from the long retardation film bonded to the bonding layer, to produce a long optical film by a roll-to-roll method. The length of the long retardation film and the transferred film along the second direction D2 was about 20 m, and a long optical film of about 20 m was produced.

[0182] (Transfer film) As shown in Figs. 19 to 21, the transfer film 50 included a substrate 51 and a bonding layer 53. The transfer film had the same configuration among Example 1, Comparative Example 1, and Comparative Example 2. Fujitac TD80UL (thickness 80 μm, TAC film (A)) manufactured by Fujifilm Corporation was used as the substrate of the transfer film. A bonding layer was laminated on this substrate to produce a long transfer film. The bonding layer was Panaclean PD-S1 (manufactured by Panac Corporation) (thickness 25 μm). The width W51 (see Fig. 12) of the transfer film along the short side direction (first direction D1) of the substrate was 1330 mm. The width W53 (see Fig. 12) of the transfer film along the short side direction (first direction D1) of the bonding layer was 1280 mm.

[0183] Example 1 As shown in FIG. 19, the long retardation film 10 of Example 1 was laminated with the transfer film 50. Both ends E53 in the first direction D1 of the bonding layer 53 of the transfer film 50 faced the second region 42 of the retardation layer 40 in the third direction D3. The substrate was peeled off from the long retardation film to transfer the retardation layer and the alignment film to the transfer film, thereby obtaining a long optical film. The retardation layer and the alignment film were torn at a position P1 in the second region in the first direction D1 facing the end E53 of the bonding layer. The portions of the retardation layer and the alignment film that were outside the torn position P1 in the first direction D1 remained on the substrate.

[0184] Comparative Example 1 As shown in FIG. 20, the long retardation film 110 of Comparative Example 1 was laminated with the transfer film 50. Both ends E53 in the first direction D1 of the bonding layer 53 of the transfer film 50 faced the first region 141 of the retardation layer 140 in the third direction D3. The substrate was peeled off from the long retardation film to transfer the retardation layer and the alignment film to the transfer film, thereby obtaining a long optical film. The retardation layer and the alignment film were torn at a position P2 in the first region in the first direction D1, and the portion on the outside in the first direction D1 remained on the substrate.

[0185] Comparative Example 2 As shown in FIG. 21, the long retardation film 210 of Comparative Example 2 was laminated with the transfer film 50. Both ends E53 in the first direction D1 of the bonding layer 53 of the transfer film 50 faced the second region 242 of the retardation layer 240 in the third direction D3. The substrate was peeled off from the long retardation film to transfer the retardation layer and the alignment film to the transfer film, thereby obtaining a long optical film. The retardation layer and the alignment film were torn at a position P3 in the second region in the first direction D1 in a part of the region along the longitudinal direction, and the part outside the position P3 in the first direction D1 remained on the substrate. The retardation layer and the alignment film were transferred to the transfer film 50 over the entire width of the second region along the first direction D1 without being torn at the position P3 facing the end E53 of the bonding layer 53 in the other wide region along the longitudinal direction.

[0186] (Evaluation Results) The occurrence of burrs on the ends of the retardation layers was confirmed for the long optical films produced as Example 1, Comparative Example 1, and Comparative Example 2. For Example 1, no burrs were observed. In Comparative Example 1 and Comparative Example 2, burrs were observed.

[0187] In Comparative Example 2, in a wide region along the longitudinal direction, the retardation layer and the alignment film were not torn at the position P3 in the second region in the first direction D1, and one of the second regions in the first direction D1 of the retardation layer was transferred to the transfer film over the entire width including its end. The alignment film was also transferred to the transfer film over the entire width including its end in a wide region along the longitudinal direction. As a result, in a part of the longitudinal direction of the long optical film obtained as Comparative Example 2, the second region of the retardation layer was present that extended outward in the first direction D1 beyond the bonding layer. The second region extending from the bonding layer was not bonded to the bonding layer. The second region extending from the bonding layer remained on the long optical film as a burr or a foreign object broken from the retardation layer. During the manufacture of the long optical film of Comparative Example 2, the part of the retardation layer that was not bonded to the bonding layer came into contact with the first region of the retardation layer, and part of the first region was damaged to the extent that it could not be handled as a product. Such a problem did not occur in Example 1 and Comparative Example 1.

[0188] Fig. 22 is a photograph showing an end portion in the first direction D1 of the retardation layer of the long optical film obtained as Example 1. Fig. 23 is a photograph showing an end portion in the first direction D1 of the retardation layer of the long optical film obtained as Comparative Example 1. Fig. 24 is an optical microscope photograph showing an end portion in the first direction D1 of the retardation layer of the long optical film obtained as Comparative Example 2. The magnification of the photographs shown in Figs. 22 to 24 is 2 times. In the photographs shown in Figs. 22 to 24, the retardation layer and the alignment film are transferred to the left region. [Explanation of symbols]

[0189] 10: long retardation film, 10R: roll, 10X: retardation film, 12: winding core, 15: intermediate, 20: substrate, 30: alignment film, 30P: alignment film, 31: central region, 32: end region, 35: first coating film, 40: retardation layer, 40P: retardation layer, 41: first region, 42: second region, 43: third region, 44: liquid crystal composition, 45: second coating film, 50: transfer film, 50R: roll, 52: polarizing layer, 53: bonding layer, 55: long optical film, 55R: roll, 55X: optical film, 60: long polarizing film, 60R: roll, 60X: polarizing film, 70: manufacturing device, 71: supply core, 72: recovery core, 73: transport roll , 76: first supply device, 77: first drying device, 78: first curing device, 78A: first exposure device, 78B: mask, 81: second supply device, 82: second drying device, 83: second curing device, 90: manufacturing device, 91: first supply core, 92: second supply core, 93: first recovery core, 94: second recovery core, 95: transport roll, 95A: first transport roll, 95B: second transport roll, 100: display device, 103: organic EL display panel, D1: first direction, D2: second direction, D3: third direction, A20: substrate slow axis, A41: first slow axis, A42: second slow axis, A43: third slow axis, θ41: first orientation angle, θ42: second orientation angle, θ43: third orientation angle

Claims

1. A long retardation film including a longitudinal direction and a transverse direction, A stretched substrate; A retardation layer overlapped with the base material, The retardation layer includes a first region, a pair of second regions, and a pair of third regions, The first region is located between the pair of second regions in the short-side direction, the pair of second regions are located between the pair of third regions in the short-side direction, The retardation layer includes a cured product of a liquid crystal composition, The second region is non-oriented, The third region is horizontally aligned.

2. the third region has a third slow axis, The long retardation film according to claim 1 , wherein a third orientation angle between the third slow axis and the longitudinal direction is 40° or more and 140° or less.

3. The first region has a first slow axis, 2 . The long retardation film according to claim 1 , wherein a first orientation angle between the first slow axis and the longitudinal direction is 10° to 80°, or 100° to 170°.

4. The long retardation film according to claim 1 , wherein the third region includes an end portion of the retardation layer in the short-side direction.

5. The long retardation film according to claim 1 , wherein the first region includes a center of the retardation layer in the short-side direction.

6. an alignment film located between the substrate, the first region, and the second region; The long retardation film according to claim 1 , wherein the third region is in contact with the base material.

7. The long retardation film according to claim 6 , wherein the alignment film includes a photo-alignment film.

8. The long retardation film according to claim 1 , wherein the substrate comprises a polyethylene terephthalate film.

9. The polyethylene terephthalate film has a slow axis, 9. The long retardation film according to claim 8, wherein an angle between the slow axis and the longitudinal direction of the polyethylene terephthalate film is 40° or more and 140° or less.

10. The long retardation film according to claim 1 , wherein the second region has a length in the short direction of at least 1 mm and at most 200 mm.

11. The long retardation film according to claim 1 , wherein a length of the third region along the short side direction is 0.5 mm or more and 50 mm or less.

12. The long retardation film according to claim 1 , wherein a length of the first region along the short side direction is six times or more a length of the second region along the short side direction.

13. An in-plane retardation Re(450) in the first region of the retardation layer at a wavelength of 450 nm is smaller than an in-plane retardation Re(550) in the first region of the retardation layer at a wavelength of 550 nm, The in-plane retardation Re(550) is smaller than the in-plane retardation Re(650) in the first region of the retardation layer at a wavelength of 650 nm, The long retardation film according to claim 1 , wherein the in-plane retardation Re(550) is 130 nm or more and 153 nm or less.

14. A step of applying an alignment film-forming composition to a long substrate having a longitudinal direction and a transverse direction to form a first coating film; a step of irradiating a central region of the first coating film, excluding end regions in the short side direction, with polarized light to form an alignment film from the first coating film, the central region of which has an alignment regulating force; applying a liquid crystal composition to an intermediate including the substrate and the alignment film to form a second coating film; and curing the second coating film to form a retardation layer including a cured product of the liquid crystal composition. The substrate is stretched, the retardation layer includes a first region facing the central region, a second region facing the end region, and a third region facing the base material on the outer side of the alignment film in the short-side direction, The method for producing a long retardation film, wherein the third region is horizontally aligned.

15. the third region has a third slow axis, The method for producing a long retardation film according to claim 14, wherein a third orientation angle between the third slow axis and the longitudinal direction is 40° or more and 140° or less.

16. The first region has a first slow axis, The method for producing a long retardation film according to claim 13, wherein a first orientation angle between the first slow axis and the longitudinal direction is 10° to 80°, or 100° to 170°.

17. The method for producing a long retardation film according to claim 14 , wherein the third region includes an end portion of the retardation layer in the short-side direction.

18. The method for producing a long retardation film according to claim 14 , wherein the first region includes a center of the retardation layer in the short-side direction.

19. The substrate includes a polyethylene terephthalate film having a slow axis, The method for producing a long retardation film according to claim 14, wherein an angle between the slow axis and the longitudinal direction of the polyethylene terephthalate film is 40° or more and 140° or less.

20. The method for producing a long retardation film according to claim 14 , wherein a length of the second region along the short side direction is 1 mm or more and 200 mm or less.

21. The method for producing a long retardation film according to claim 14, wherein a length of the third region along the short side direction is 0.5 mm or more and 50 mm or less.

22. The method for producing a long retardation film according to claim 14 , wherein a length of the first region along the short side direction is six times or more a length of the second region along the short side direction.

23. An in-plane retardation Re(450) in the first region of the retardation layer at a wavelength of 450 nm is smaller than an in-plane retardation Re(550) in the first region of the retardation layer at a wavelength of 550 nm, The in-plane retardation Re(550) is smaller than the in-plane retardation Re(650) in the first region of the retardation layer at a wavelength of 650 nm, The method for producing a long retardation film according to any one of claims 14 to 22, wherein the in-plane retardation Re(550) is 130 nm or more and 153 nm or less.

24. A step of laminating the long retardation film according to any one of claims 1 to 13 onto a long transfer film including a bonding layer; and peeling off the base material from the long retardation film bonded to the bonding layer.

25. The long optical film includes the first region and a part of the second region of the retardation layer, The method for producing a long optical film according to claim 24 , wherein the third region and a remainder other than the part of the second region of the retardation layer remain on the base material.

26. 25. The method for producing a long optical film according to claim 24, wherein, when the long retardation film is laminated on the transfer film, the second region faces an end of the bonding layer in the short side direction, and the third region is located outside the bonding layer in the short side direction and faces the substrate of the transfer film.

27. The method for producing a long optical film according to claim 24 , wherein the transferred film includes a polarizing layer including a polarizer.

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