Structure manufacturing method and structure

Abstract

To provide a structure manufacturing method which enables easy fabrication of a structure having no overflowed curable resin left on the periphery and a fine concavo-convex structure formed only on a desired portion of a substrate, and to provide such structure.SOLUTION: A structure manufacturing method is provided, comprising modification step of forming an unmodified portion 10 and a modified portion 20 on a surface of a substrate 101, coating step of coating the surface with a curable resin, a structure forming step of forming a fine concavo-convex structure on the curable resin coating the substrate 101, a curing step of curing the curable resin, and a removal step of removing the cured curable resin coating the unmodified portion 10.SELECTED DRAWING: Figure 1G

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a structure and a structure.

Background Art

[0002] Plastic lenses such as COP (Cyclo - Olefin Polymers) or COC (Cyclo - Olefin Copolymers) are widely used in lenses such as VR (Virtual Reality), AR (Augmented Reality), or camera modules. It is known that a high transmittance can be ensured by imparting a fine shape such as a moth - eye structure to the surface of a plastic lens such as COP or COC.

[0003] As a method for forming a fine structure, a nano - imprint method is known in which a curable resin applied on the surface of a substrate such as a plastic lens is pressed with a mold engraved with a fine pattern to transfer the fine pattern to the curable resin.

[0004] For example, in Patent Document 1, a transfer object in which a material to be molded (photo - curable resin) is provided on a substrate is placed on a stage, and a mold held via a spring portion is pressed against the transfer object using a roller to transfer a fine concavo - convex structure formed on the mold to the transfer object.

[0005] Also, Patent Document 2 discloses a method for transferring a fine concavo - convex structure to a photo - curable resin on the surface of a substrate. Specifically, this method includes the steps of first applying a photo - curable resin on a substrate so as to cover the surface of the substrate and protrude beyond the outer periphery of the substrate, then pre - curing only the photo - curable resin of the protruding portion, and then pressing against the photo - curable resin on the surface of the substrate through a mold having a fine concavo - convex structure.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-5085 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-213423 [Summary of the Invention] [Problems to be Solved by the Invention]

[0007] However, in the prior art described in Patent Document 1, when pressing against the object to be transferred using a roller, the molding material (photo-curable resin) may protrude to a portion on the substrate where the formation of the fine concavo-convex structure is not intended. If the photo-curable resin is uncured and liquid at the edge portion of the lens corresponding to the portion, the edge portion or the portion where the fine concavo-convex structure is formed inside the edge portion may be contaminated, and the characteristics as an optical element may be impaired. Further, in the prior art described in Patent Document 2, the addition of the pre-curing step increases the complexity of the process.

[0008] In the conventional method, in the case of 3D lenses or nanoimprinting on individual substrates, when the curable resin protruding from the portion where the formation of the fine concavo-convex structure is intended cures, the shape of the edge portion of the lens becomes larger than the predetermined design value, and there is a problem that it is difficult to function as an optical element. Therefore, there has been a need for a method for manufacturing a structure that can easily form a fine concavo-convex structure only on a desired portion of a substrate without the curable resin protruding to the surroundings.

[0009] An object of the present invention is to provide a method for manufacturing a structure in which a fine concavo-convex structure is formed only on a desired portion of a substrate, and the structure, in which the curable resin does not protrude to the surroundings easily. [Means for Solving the Problems]

[0010] That is, the gist configuration of the present invention is as follows. (1) A manufacturing method of a structure, comprising: a modification step of forming an unmodified portion and a modified portion on the surface of a substrate; a coating step of applying a curable resin to the surface; a structure formation step of forming a fine concavo-convex structure on the curable resin applied to the substrate; a curing step of curing the curable resin; and a removal step of removing the cured product of the curable resin applied to the unmodified portion.

[0011] (2) The modification step in the manufacturing method of the structure according to (1) above includes: a step of covering a first portion of the surface with a mask; a step of modifying a second portion of the surface that is not covered with the mask as the modified portion; and a step of removing the mask.

[0012] (3) The structure formation step in the manufacturing method of the structure according to (1) or (2) above is performed using a mold having an inverted shape of the fine concavo-convex structure.

[0013] (4) In the manufacturing method of the structure according to any one of (1) to (3) above, the water contact angle of the modified portion formed in the modification step is at least 40 degrees smaller than the water contact angle of the unmodified portion.

[0014] (5) The modification step in the manufacturing method of the structure according to (2) above is performed by a surface modification treatment selected from the group consisting of excimer treatment, silane coupling treatment, and primer treatment.

[0015] (6) The modification step in the manufacturing method of the structure according to any one of (1) to (5) above includes a material application step of forming the unmodified portion with a first material on a first portion of the surface and forming the modified portion with a second material different from the first material on a second portion of the surface different from the first portion.

[0016] (7) In the manufacturing method of the structure according to any one of (1) to (6) above, the substrate is formed of a cycloolefin resin.

[0017] A structure comprising a substrate having an unmodified portion and a modified portion on its surface, wherein a fine uneven structure layer made of a curable resin is disposed only on the modified portion of the substrate.

[0018] (9) The structure according to (8) above, wherein the water contact angle of the modified portion is at least 40 degrees smaller than the water contact angle of the unmodified portion.

[0019] (10) The structure according to (8) or (9) above, wherein the unmodified portion is formed of a first material on a first portion of the surface, and the modified portion is formed of a second material different from the first material on a second portion of the surface.

[0020] (11) The structure according to any one of (8) to (10) above, wherein the substrate is formed of a cycloolefin resin. [Effect of the Invention]

[0021] According to the present invention, it is possible to provide a method for manufacturing a structure in which a fine uneven structure is formed only on a desired portion of a substrate, and the structure, in which the curable resin does not protrude to the surroundings easily. [Brief Description of the Drawings]

[0022]

Figure 1A

Figure 1B

Figure 1C

Figure 1D

Figure 1E

Figure 1F

Figure 1G

Embodiments for Carrying Out the Invention

[0023] Hereinafter, the present invention will be described in detail based on embodiments.

[0024] (Method for Manufacturing a Structure) The method for manufacturing a structure of the present invention includes a modification step of forming an unmodified portion and a modified portion on the surface of a base material, a coating step of applying a curable resin to the surface, a structure forming step of forming a fine uneven structure in the curable resin applied to the base material, a curing step of curing the curable resin, and a removing step of removing the cured product of the curable resin applied to the unmodified portion.

[0025] In this specification, the "unmodified portion" refers to a portion of the surface of the base material that has not been subjected to surface modification treatment, or a portion formed of a first material on the surface of the base material. In this specification, the "modified portion" refers to a portion of the surface of the base material that has been subjected to surface modification treatment, or a portion formed of a second material different from the first material on the surface of the base material. In the relationship between the modified portion and the unmodified portion in this specification, the water droplet contact angle of the modified portion is, for example, 40 degrees or more smaller than the water droplet contact angle of the unmodified portion. In this specification, the surface modification treatment is a treatment selected from the group consisting of excimer treatment, silane coupling treatment, and primer treatment.

[0026] In this specification, the water droplet contact angle is measured by the θ / 2 method based on JIS R3257 "Test Method for Wettability of Substrate Glass Surface". Specifically, the angle formed by the boundary line between the water droplet and the water droplet contact object, and a straight line connecting one of the contact points of the water droplet and the water droplet contact object and the apex of the water droplet is measured by an optical reading device, and the obtained value is doubled.

[0027] In this specification, excimer treatment means irradiating a substrate with light (excimer light) having a wavelength of 150 nm to 200 nm. In this specification, silane coupling treatment means dropping or spraying a silane coupling agent onto a substrate. In this specification, primer treatment means applying a silane coupling material onto a substrate.

[0028] Hereinafter, a method for manufacturing a structure according to an embodiment of the present invention (hereinafter, may be referred to as "the manufacturing method of the present embodiment") will be described with reference to FIGS. 1A to 1G.

[0029] <Modification step> The modification step is a step of forming an unmodified portion 10 and a modified portion 20 on the surface of the substrate 101. The modification step preferably includes a step of covering with a mask, a step of modifying, and a step of removing the mask. According to this method, the modified portion 20 can be formed on an arbitrary portion of the surface of the substrate 101, and the fine concavo-convex structure layer 102 made of a curable resin can be disposed only on the modified portion 20 of the substrate 101. <<Step of covering with a mask>> The step of covering with a mask is a step of covering, with a mask, a portion of the surface of the substrate 101 where the formation of the fine concavo-convex structure layer 102 is not intended. In the manufacturing method of the present embodiment, as shown in FIG. 1A, the first portion 10a of the surface of the substrate 101 is covered with the mask 150. The first portion 10a corresponds to a portion where the formation of the fine concavo-convex structure layer 102 is not intended. Here, a portion of the substrate 101 that is not covered with the mask 150 is defined as the second portion 20a. The second portion 20a corresponds to a portion where the formation of the fine concavo-convex structure layer 102 is intended. <<Modifying step>> The modification step is a step of performing surface modification treatment on the second portion 20a not covered by the mask on the surface of the substrate 101 as a modified portion by a treatment selected from the group consisting of excimer treatment, silane coupling treatment, and primer treatment. In the manufacturing method of the present embodiment, as shown in FIG. 1B, excimer light is irradiated onto the upper surface of the substrate 101. At this time, since the excimer light does not pass through the mask 150, the first portion 10a covered by the mask 150 on the surface of the substrate 101 is not modified and corresponds to the unmodified portion 10. Surface modification treatment is performed only on the second portion 20a not covered by the mask 150, and the second portion 20a corresponds to the modified portion 20. <<Step of removing the mask>> The step of removing the mask 150 is a step of removing the mask 150 that covered the first portion 10a on the surface of the substrate 101. After removing the mask 150, the substrate 101 is in the state shown in FIG. 1C. In FIG. 1C, similar to FIG. 1B, the portion where the surface is modified is the modified portion 20, and the portion where the surface is not modified is the unmodified portion 10.

[0030] In the above modification step, it has been described that the surface modification treatment of the substrate 101 is performed by excimer treatment, but it is not limited thereto. Instead of or in addition to the surface modification treatment of the substrate 101, an unmodified portion 10 made of a first material may be formed on the first portion 10a of the surface of the substrate 101, and a modified portion 20 made of a second material different from the first material may be formed on the second portion 20a.

[0031] The water droplet contact angle of the modified portion 20 is preferably at least 40 degrees smaller than the water droplet contact angle of the unmodified portion 10, more preferably at least 50 degrees smaller, and even more preferably at least 60 degrees smaller. By performing surface modification treatment so that the water droplet contact angle of the modified portion 20 is at least 40 degrees smaller than the water droplet contact angle of the unmodified portion 10, the wettability of the curable resin described later with respect to the modified portion 20 is improved.

[0032] <Coating step> The coating process is a process of applying (potting) a curable resin onto the surface of the base material 101 that has undergone the modification process. In the manufacturing method of the present embodiment, as shown in FIG. 1D, a UV (Ultra-Violet) curable resin 160 is applied onto the base material 101. The UV curable resin 160 is not particularly limited, and examples thereof include a UV curable acrylic resin and a UV curable epoxy resin. Further, various additives such as a curing initiator may be added to the UV curable resin 160 as necessary.

[0033] <Structure formation process> The structure formation process is a process of forming a fine concavo-convex structure in the UV curable resin 160 applied to the base material 101 in the coating process. Specifically, a mold having a fine concavo-convex structure is placed on the base material 101 via the UV curable resin 160, and the UV curable resin 160 is pressed from above the mold. The fine concavo-convex structure formed in the mold preferably has an inverted shape of the fine concavo-convex structure to be formed on the base material 101. The mold having the fine concavo-convex structure is not particularly limited, and examples thereof include a thin film optical body on a carrier film or a mold. Further, the fine concavo-convex structure is not particularly limited, and examples thereof include a moth-eye structure, a microlens array structure, and a diffraction structure. In the manufacturing method of the present embodiment, as shown in FIG. 1E, a film mold 250 having a fine concavo-convex structure is placed on the base material 101 via the UV curable resin 160. Then, the UV curable resin 160 is pressed from above the film mold 250. Here, by adjusting the pressure and time during pressing, the thickness of the fine concavo-convex structure layer 102 described later that is finally obtained can be adjusted.

[0034] <Curing process> The curing step is a step of curing a curable resin that is pressed from above a mold in which a fine uneven structure is formed in the structure forming step. The method of curing the curable resin is preferably selected from any of UV curing, heat curing, or room temperature chemical reaction according to the properties of the curable resin. In the manufacturing method of the present embodiment, as shown in FIG. 1E, the UV curable resin 160 is cured by UV irradiation. After the UV curable resin 160 is cured, when the film mold 250 having the fine uneven structure is peeled off, as shown in FIG. 1F, a fine uneven structure layer 102 is formed on the base material 101.

[0035] <Removal step> The removal step is a step of removing the cured product of the curable resin applied to the non-modified portion 10. For example, the removal step is a step of removing the fine uneven structure layer 102 on the non-modified portion 10 among the fine uneven structure layers 102 formed on the base material 101. In the manufacturing method of the present embodiment, the fine uneven structure layer 102 formed on the non-modified portion 10 is removed to obtain the structure 100 shown in FIG. 1G. Due to the surface modification treatment in the modification step, the fine uneven structure layer 102 on the modified portion 20 is more difficult to peel off than the fine uneven structure layer 102 on the non-modified portion 10, so it is possible to peel off only the fine uneven structure layer 102 on the non-modified portion 10.

[0036] (Structure) The structure 100 of the present invention includes a base material 101 having a non-modified portion 10 and a modified portion 20 on the surface, and a fine uneven structure layer 102 made of the UV curable resin 160 is disposed only on the modified portion 20 of the base material 101. In the present invention, "disposed only on the modified portion" does not include a mode in which the UV curable resin 160 inadvertently protrudes to a location other than the modified portion 20 (specifically, the non-modified portion 10).

[0037] The structure 100 according to an embodiment of the present invention (hereinafter sometimes referred to as "the structure of the present embodiment") includes a base material 101 having a non-modified portion 10 and a modified portion 20 on the surface, and a fine uneven structure layer 102 made of the UV curable resin 160 disposed only on the modified portion 20 of the base material 101, as shown in FIG. 1G.

[0038] <Base material> The base material 101 used in this embodiment is preferably formed of a cycloolefin resin. The base material 101 used in this embodiment can be appropriately selected according to the purpose, and examples thereof include COP or COC. The base material 101 is preferably transparent. Further, the surface of the base material 101 may be coated. Here, "transparent" means that the transmittance of light having a wavelength belonging to the visible light band (approximately 360 nm to 830 nm) is high, for example, the transmittance of the light is 70% or more.

[0039] <Modified portion and unmodified portion> In this embodiment, the water contact angle of the modified portion 20 is preferably 40 degrees or more smaller than the water contact angle of the unmodified portion 10, more preferably 50 degrees or more smaller, and even more preferably 60 degrees or more smaller. The modified portion 20 and the unmodified portion 10 may be distinguished from each other by subjecting a part of the surface of the base material 101 to a surface modification treatment to form the modified portion 20. Alternatively, the modified portion 20 and the unmodified portion 10 may be distinguished from each other by forming the unmodified portion 10 of the first material on the first portion 10a of the surface of the base material 101 and forming the modified portion 20 of the second material different from the first material on the second portion 20a. For example, the first material may be a material different from the second material in the second portion 20a, such as fluorine or silicone.

[0040] <Microscopic uneven structure layer> In the microscopic uneven structure layer 102 of this embodiment, a fine uneven pattern (a convex portion that is convex in the thickness direction of the microscopic uneven structure and a concave portion that is concave in the thickness direction of the microscopic uneven structure) is formed. Thereby, the antireflection performance can be improved. The convex portions and the concave portions may be arranged periodically (for example, in a staggered grid pattern or a rectangular grid pattern), or may be arranged randomly. Further, the shapes of the convex portions and the concave portions are not particularly limited, and may be bullet-shaped, pyramid-shaped, columnar, needle-shaped, or the like. Note that the shape of the concave portion means the shape formed by the inner wall of the concave portion.

[0041] The thickness of the fine concavo-convex structure layer 102 at the boundary (points A and B in Fig. 1G) between the modified portion 20 and the unmodified portion 10 is preferably 1 μm or less, more preferably 0.5 μm or less, and even more preferably 0.1 μm or less.

[0042] Also, the depth (height of the convex portion) of the concave portion in the concavo-convex pattern of the fine concavo-convex structure layer 102 is not particularly limited, but is preferably 150 nm or more, more preferably 190 nm or more, and preferably 500 nm or less, more preferably 230 nm or less. On the other hand, the thickness of the portion of the fine concavo-convex structure layer 102 that is not the fine concavo-convex structure is preferably 250 nm or less. If the thickness of the portion of the fine concavo-convex structure layer 102 that is not the fine concavo-convex structure is 250 nm or less, the vibration (ripple) of the reflection spectrum due to multiple reflections between the substrate 101 and the fine concavo-convex structure layer 102 becomes smaller, and color unevenness or reflection deterioration can be further suppressed. From the same viewpoint, the thickness of the portion of the fine concavo-convex structure layer 102 that is not the fine concavo-convex structure is more preferably 200 nm or less, even more preferably 100 nm or less, and particularly preferably 50 nm or less. On the other hand, from the viewpoint of practicality, the thickness of the portion of the fine concavo-convex structure layer 102 that is not the fine differential concavo-convex structure can be 0.01 nm or more. Note that the thickness of the portion of the fine concavo-convex structure layer 102 that is not the fine concavo-convex structure refers to the distance in the stacking direction or film thickness direction between the surface where the fine concavo-convex structure layer 102 and the substrate 101 are in contact and the apex of the deepest concave portion of the formed fine concavo-convex structure.

[0043] The average period (pitch) of the concavo-convex pattern on the upper surface of the fine concavo-convex structure layer 102 is preferably equal to or less than the visible light wavelength (for example, 830 nm or less), more preferably 350 nm or less, even more preferably 280 nm or less, and more preferably 100 nm or more, even more preferably 150 nm or more. By setting the pitch of the concavo-convex pattern on the upper surface of the fine concavo-convex structure layer 102 to be equal to or less than the visible light wavelength, in other words, by making the upper surface of the fine concavo-convex structure layer 102 a so-called moth-eye structure, a further structure for antireflection performance can be achieved.

[0044] Here, the average period of the uneven pattern is the arithmetic mean of the distances between adjacent convex portions and between adjacent concave portions. Note that the uneven pattern and thickness of the fine uneven structure layer 102 can be observed by, for example, a scanning electron microscope (SEM) or a cross-sectional transmission electron microscope (cross-sectional TEM). Further, as a method for calculating the average period, for example, several combinations of adjacent convex portions and several combinations of adjacent concave portions are picked up, the distances between the convex portions and the distances between the concave portions constituting each combination are measured, and the measured values are averaged.

[0045] The fine uneven structure layer 102 used in the present embodiment is made of a curable resin. The curable resin is not particularly limited, and examples thereof include a UV curable resin 160. Examples of the UV curable resin 160 include a UV curable acrylic resin and a UV curable epoxy resin.

[0046] In the present embodiment, when the refractive indices of the base material 101 and the fine uneven structure layer 102 are n0 and n1, respectively, the absolute value of the refractive index difference between n0 and n1 is preferably within 0.2. By satisfying this condition, the vibration (ripple) of the reflection spectrum due to multiple reflections between the layers becomes small, color unevenness or reflection deterioration is suppressed, and a structure with high transmittance can be obtained.

Example

[0047] Next, the present invention will be described more specifically using examples and comparative examples, but the present invention is not limited to the following examples.

[0048] (Example 1) According to the manufacturing method of the present invention, a structure 100 having a base material 101 having an unmodified portion 10 and a modified portion 20 on the surface and a fine uneven structure layer 102 made of a UV curable resin 160 disposed only on the modified portion 20 of the base material 101 was produced by the method shown in FIGS. 1A to 1G.

[0049] Specifically, first, a base material 101 with a thickness of 3 mm composed of COC was prepared. When the portion on the surface of the base material 101 where the fine concavo-convex structure layer 102 was to be formed was defined as the second portion 20a and the other portion as the first portion 10a, the first portion 10a on the surface of the base material 101 was covered with a mask 150 (FIG. 1A). Next, excimer light was irradiated from above the base material 101, and excimer treatment was performed on the second portion 20a on the surface of the base material 101 (FIG. 1B). The mask 150 that had covered the first portion 10a on the surface of the base material 101 was removed. After removing the mask 150, the portion with the modified surface was defined as the modified portion 20, and the unmodified portion as the unmodified portion 10 (FIG. 1C). Next, a UV curable resin 160 was applied to the surface of the base material 101 (FIG. 1D). As the UV curable resin 160, a UV curable resin (SK1120 manufactured by DXC) was used. A film mold 250 with a moss-eye structure formed as a fine concavo-convex structure was laminated on the UV curable resin 160 and pressed at 0.1 MPa for 10 seconds. The fine concavo-convex structure of the film mold 250 used had a moss-eye structure with a pitch of 200 nm and a depth of the concave portion (height of the convex portion) of 200 nm. At this time, the film thickness of the UV curable resin 160 was 0.1 μm. UV irradiation was performed from above the film mold 250 to cure the UV curable resin 160 (FIG. 1E). The film mold 250 was peeled off, and the fine concavo-convex structure layer 102 was formed (FIG. 1F). Next, the fine concavo-convex structure layer 102 formed on the unmodified portion 10 was peeled off to obtain the structure 100 (FIG. 1G). Also, the refractive index n0 of the base material 101 was 1.52, and the refractive index n1 of the fine concavo-convex structure layer 102 was 1.52.

[0050] Here, the thickness of the fine concavo-convex structure layer 102 at the boundary between the modified portion 20 (the portion where the formation of the fine concavo-convex structure was intended) and the unmodified portion 10 (the portion where the formation of the fine concavo-convex structure was not intended) was about 0.1 μm. Also, the thickness of the portion of the fine concavo-convex structure layer 102 that was not the fine concavo-convex structure was about 0.1 μm.

[0051] Next, the water contact angle of the modified portion 20 (the portion intended to form the fine concavo-convex structure) of the structure 100, the water contact angle of the non-modified portion 10 (the portion not intended to form the fine concavo-convex structure), the difference in the water contact angle between the modified portion 20 and the non-modified portion 10, the peeling of the excess curing agent, and the protrusion to the edge portion were measured. The evaluation results are shown in Table 1. The water contact angles of the modified portion 20 and the non-modified portion 10 were measured before applying the UV curable resin 160 to the base material 101. Also, the peeling of the excess curing agent indicates the possibility of peeling of the fine concavo-convex structure layer 102 formed on the non-modified portion 10 (the portion not intended to form the fine concavo-convex structure). The protrusion to the edge portion indicates the presence or absence of the UV curable resin 160 on the non-modified portion 10 (the portion not intended to form the fine concavo-convex structure).

[0052] (Example 2) A structure 100 similar to that of Example 1 was fabricated, except that a film mold 250 with a carrier film of a thin film body having a fine concavo-convex structure with a thickness of 0.5 μm was used as a mold for forming the fine concavo-convex structure in the UV curable resin 160. The fine concavo-convex structure of the film mold 250 with the carrier film was a moth-eye structure with a pitch of 200 nm and a depth of the concave portion (height of the convex portion) of 200 nm. The film mold 250 having the above fine concavo-convex structure was laminated on the UV curable resin 160 and pressed at 0.1 MPa for 10 seconds. At this time, the thickness of the thinnest portion of the UV curable resin 160 was 0.1 μm. The UV curable resin 160 was cured by irradiating UV from above the film mold 250 to form a peelable fine concavo-convex structure layer 102. The thickness of the fine concavo-convex structure layer 102 at the boundary between the modified portion 20 (the portion intended to form the fine concavo-convex structure) and the non-modified portion 10 (the portion not intended to form the fine concavo-convex structure) was about 0.1 μm. Also, the thickness of the portion of the fine concavo-convex structure layer 102 that was not the fine concavo-convex structure was about 0.1 μm. In the same manner as in Example 1, the water contact angle of the modified portion 20, the water contact angle of the non-modified portion 10, the difference in the water contact angle between the modified portion 20 and the non-modified portion 10, the peeling of the excess curing agent, and the protrusion to the edge portion were evaluated. The results are shown in Table 1.

[0053] (Comparative Example 1) When performing the modification process, a structure 100 similar to that of Example 1 was fabricated, except that the parts where the formation of the fine uneven structure was not intended were not covered with a mask, and excimer treatment was performed to apply a surface modification treatment to the entire surface of the base material 101. The thickness of the fine uneven structure layer 102 at the boundary between the part where the formation of the fine uneven structure was intended and the part where the formation of the fine uneven structure was not intended was 2 μm. Also, the thickness of the part of the fine uneven structure layer 102 that was not the fine uneven structure was 2 μm. Similar to Example 1, the water droplet contact angle of the part where the formation of the fine uneven structure was intended, the water droplet contact angle of the part where the formation of the fine uneven structure was not intended, the difference between them, the peeling of the excess curing agent, and the overhang to the edge part were evaluated. The results are shown in Table 1. The water droplet contact angle of the part where the formation of the fine uneven structure was intended and the water droplet contact angle of the part where the formation of the fine uneven structure was not intended were measured before applying the UV curable resin 160 to the base material 101.

[0054] (Comparative Example 2) When performing the modification process, a structure 100 similar to that of Example 2 was fabricated, except that the parts where the formation of the fine uneven structure was not intended were not covered with a mask, and excimer treatment was performed to apply a surface modification treatment to the entire surface of the base material 101. The thickness of the fine uneven structure layer 102 at the boundary between the part where the formation of the fine uneven structure was intended and the part where the formation of the fine uneven structure was not intended was 2 μm. Also, the thickness of the part of the fine uneven structure layer 102 that was not the fine uneven structure was 2 μm. Similar to Example 1, the water droplet contact angle of the part where the formation of the fine uneven structure was intended, the water droplet contact angle of the part where the formation of the fine uneven structure was not intended, the difference between them, the peeling of the excess curing agent, and the overhang to the edge part were evaluated. The results are shown in Table 1. The water droplet contact angle of the part where the formation of the fine uneven structure was intended and the water droplet contact angle of the part where the formation of the fine uneven structure was not intended were measured before applying the UV curable resin 160 to the base material 101.

[0055] [Table 1]

[0056] From Table 1, it can be seen that for the structure 100 according to Example 1 and Example 2, the difference in the water droplet contact angle between the modified part 20 (the part where the formation of the fine concavo-convex structure is intended) and the non-modified part 10 (the part where the formation of the fine concavo-convex structure is not intended) is 40 degrees or more, the excess curing agent can be peeled off, and there is no overhang at the edge part. Furthermore, it can be seen that the thickness of the fine concavo-convex structure layer 102 at the boundary between the modified part 20 and the non-modified part 10 is 0.1 μm or less. On the other hand, for the structure 100 according to Comparative Example 1 and Comparative Example 2, since the difference in the water droplet contact angle between the part where the formation of the fine concavo-convex structure is intended and the part where the formation of the fine concavo-convex structure is not intended on the surface of the base material 101 is 0, the excess curing agent cannot be peeled off, and there is also an overhang at the edge part. Furthermore, it can be seen that the thickness of the fine concavo-convex structure layer 102 at the boundary between the part where the formation of the fine concavo-convex structure is intended and the part where the formation of the fine concavo-convex structure is not intended is 2 μm.

Industrial Applicability

[0057] According to the present invention, it is possible to provide an easily manufactured method for a structure in which a fine concavo-convex structure is formed only on a desired part of a base material without the curable resin protruding to the surroundings, and the structure itself. According to the present invention, since the fine concavo-convex structure can be formed without inhibiting the original shape of the base material on which the fine concavo-convex structure is formed, problems such as malfunctions when setting in a housing or misalignment of optical alignment can be suppressed. Furthermore, according to the present invention, since the curable resin protruding to the part where the formation of the fine concavo-convex structure layer 102 is not intended also cures, the excess part can be removed without contaminating the surroundings. Therefore, a high-quality process can be realized.

Explanation of Reference Numerals

[0058] 10 Non-modified part 20 Modified part 10a First part 20a Second part 100 Structure 101 Base material 102 Fine concavo-convex structure layer 150 Mask 160 UV curable resin 250 Film mold

Claims

1. A modification step of forming an unmodified portion and a modified portion on the surface of a substrate; A coating step of applying a curable resin to the surface; A structure forming step of forming a fine uneven structure on the curable resin applied to the substrate; A curing step of curing the curable resin; A removing step of removing the cured product of the curable resin applied to the unmodified portion, comprising: A method for manufacturing a structure.

2. The modification step includes: A step of covering a first portion of the surface with a mask; A step of modifying a second portion of the surface that is not covered with the mask as the modified portion; A step of removing the mask, The method for manufacturing a structure according to Claim 1.

3. The structure forming step is performed using a mold having an inverted shape of the fine uneven structure, The method for manufacturing a structure according to Claim 1.

4. The water droplet contact angle of the modified portion formed in the modification step is at least 40 degrees smaller than the water droplet contact angle of the unmodified portion, The method for manufacturing a structure according to Claim 1.

5. The modifying step is performed by a surface modification treatment selected from the group consisting of excimer treatment, silane coupling treatment, and primer treatment, The method for manufacturing a structure according to Claim 2.

6. The modification step includes a material application step of forming the unmodified portion of the first material on a first portion of the surface, and forming the modified portion of the second material different from the first material on a second portion of the surface different from the first portion, The method for manufacturing a structure according to Claim 1.

7. The substrate is formed of a cycloolefin resin, The method for manufacturing a structure according to Claim 1.

8. A substrate having an unmodified portion and a modified portion on the surface, A fine uneven structure layer composed of a curable resin is disposed only on the modified portion of the substrate, A structure.

9. The water droplet contact angle of the modified portion is at least 40 degrees smaller than the water droplet contact angle of the unmodified portion, The structure according to Claim 8.

10. The unmodified portion is formed of a first material on a first portion of the surface, The modified portion is formed of a second material different from the first material on a second portion of the surface, The structure according to Claim 8.

11. The substrate is formed of a cycloolefin resin, The structure according to Claim 8.

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