JP2014139667A - Transparent body and fitting - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a transparent body which enables the inside and the outside with the transparent body sandwiched therebetween to be more clearly observed, improves visibility of the transparent body without largely impairing a function of improving daylighting, and can prevent collision and the like, and to achieve a fitting including the transparent body.SOLUTION: A transparent body has a formation region 4 of anti-reflective minute projections, and a non-formation region 5 of the anti-reflective minute projections, on at least one surface 2s of a transparent base material 2. In the formation region of the anti-reflective minute projections, the minute projections are arranged in close contact with each other, and a space between the adjacent minute projections is a shortest wavelength of a wavelength band of electromagnetic waves preventing reflection, or less. The transparent body is used for observation or daylighting of at least the other surface 2r from one surface 2s.

Description

  The invention of the present application is a transparent body for preventing reflection by arranging a large number of minute protrusions closely at intervals of not more than the shortest wavelength of the electromagnetic wave wavelength band for preventing reflection, in particular, window glass, glass door, show window, showcase, etc. The present invention relates to a transparent body that is used in the above and a joinery using the transparent body.

  In recent years, the use of a transparent body that prevents reflection by increasing the number of minute projections closely spaced at an interval equal to or shorter than the shortest wavelength in the wavelength band of electromagnetic waves for preventing reflection has been increasing.

  A method of closely arranging a large number of microprotrusions on the surface to prevent reflection uses a so-called moth-eye structure, and the refractive index for incident light is continuously measured in the thickness direction of the substrate. By changing this, the discontinuous surface of the refractive index disappears to prevent reflection.

  As described in Patent Document 1, the appearance of such a transparent body is old, but at that time, the process for producing a large number of microprojections was costly and difficult to apply to a large area. That is, if the description of patent document 1 is demonstrated, a photoresist pattern etc. will be apply | coated to the surface with respect to optical components, such as a lens which should reduce surface reflection, and it will expose, develop, etc. This is a method of forming fine irregularities directly on the surface of the optical component for each product by producing and corroding the glass substrate with the pattern. However, with this method, the work efficiency is poor and the productivity (mass productivity) required for industrial products cannot be obtained. Therefore, its use has been limited to fields with a relatively small area and high added value, such as optical equipment.

  As described in Patent Document 2, the production cost was reduced by using a plate produced by utilizing anodization of aluminum.

Further, as described in Patent Document 3, for the fine unevenness, the minimum wavelength in the vacuum in the wavelength band of visible light is λ _MIN , and the period at the most convex portion of the fine unevenness is P _MAX . Sometimes, the cross-sectional area occupancy ratio of the material portion of the base material in the cross-section when it is assumed that P _MAX ≦ λ _MIN and the fine unevenness is cut along a plane orthogonal to the unevenness direction. , The unevenness that gradually increases gradually from the most convex part of the fine unevenness to the most concave part, and the above-mentioned fine unevenness has a peak-side shape having the most convex part and a valley having the most concave part. Compared to the shape on the side, the configuration having a sharper shape improves the light transmittance and the like.

Japanese Patent Laid-Open No. 50-70040 Special Table 2003-531962 Japanese Patent No. 4197100

  Thus, by reducing the manufacturing cost, such a transparent body 1 is made of, for example, glass or acrylic resin (acrylic glass) used for a glass window, a glass door, a glass wall (surface), a show window, a show case, or the like. Applications for transparent bodies are expanding. When observing the inside and outside of a transparent body, the so-called reflection is small, and it is possible to observe more clearly without being aware of the presence of the transparent body, or to improve the daylighting. Is possible.

  However, in these applications, improved transparency and reduced reflectivity significantly reduce the visibility of these transparent bodies themselves, so birds, animals, or humans collide with transparent bodies without noticing the presence of transparent bodies. However, there is a risk of injury due to damage as a result of the collision. As countermeasures, conventionally, the presence of a transparent body is visually recognized by laminating characters, symbols, figures, etc. made of colored ink, colored film, or metal plate on a part of the surface of a transparent body (window glass, etc.). Was also done. However, these characters have the disadvantage that they impede visibility and impair aesthetics.

  In addition, when used on window glass, etc. for the purpose of improving daylighting, it is possible to observe the interior clearly from the outdoors, especially during the daytime. Produces no side effects.

  The present invention has been made in view of such a situation, and makes it possible to observe the inside and outside of the transparent body more clearly, and greatly impairs the function and appearance for improving the daylighting. It is an object of the present invention to realize a joinery that includes the transparent body and the transparent body that can improve the visibility of the transparent body and prevent collision and the like. In addition, it allows you to observe the inside and outside of the transparent body more clearly, and without damaging the function of improving daylighting, etc. It is an object to realize a joinery configured to include the transparent body considered and the transparent body.

  In view of the above situation, earnest research and development is proceeding, and claim 1 of the present invention claims that at least one surface 2s of the transparent substrate 2 has antireflection microprojection formation region 4 and antireflection microprojection non-reflection. The transparent body 1 having the formation region 5, wherein the antireflection microprojection formation region 4 has the microprojections 3 arranged in close contact with each other, and the interval between the adjacent microprojections 3 is an electromagnetic wave for preventing reflection. It is a transparent body characterized by being less than or equal to the shortest wavelength of the wavelength band.

  In addition, according to the second aspect of the present invention, a transparent region having the antireflection microprojection formation region 4 and the antireflection microprojection non-formation region 5 is formed on both surfaces 2s and 2r of the transparent substrate 2, respectively. The antireflection microprojection formation region 4 formed on one surface of the body 1 and the antireflection microprojection formation region 4 formed on the other surface are in the normal direction of the transparent substrate 2 The transparent body 1 according to claim 1, wherein:

  In addition, according to claim 3 of the present invention, at least a part of the microprojections 3 are microprojections 3b, 3c,... Having a plurality of apexes. This is a transparent body 1.

  In addition, a fourth aspect of the present invention is a joinery comprising the transparent body according to any one of the first to third aspects.

  According to the first aspect of the present invention, the antireflection microprojection formation region 4 and the antireflection microprojection non-formation region 5 are formed, so that there is almost no reflection (reflection). The projection formation region 4 and the antireflection microprojection non-formation region 5 having reflection (reflection) are simultaneously seen by the eyes. Therefore, by improving the visibility of the transparent body 1 itself, attention is drawn and it becomes easy to be aware of the presence of the transparent body 1, and it is possible to prevent a person from colliding with the transparent body 1. Moreover, the visibility (perspective property) or aesthetic appearance is not impaired.

  In addition, when applied to a partition of a living space, a window or the like, an antireflection micro-projection formation region 4 is provided in an area where lighting is important (for example, above the human eye), and an area that is not desired to be looked at (for example, the human eye) By making the neighborhood height) the non-reflective microprojection forming area 5, the area that you don't want to look into is reflected like a conventional window, making it difficult to see the inside and protecting lighting and privacy It is possible to achieve both.

  Furthermore, by providing the structural requirement according to claim 2, the difference in light reflectance between the antireflection microprojection formation region 4 and the antireflection microprojection non-formation region 5 becomes larger. The visibility of the transparent body 1 is greatly improved. Therefore, it is easy to call attention, and collisions can be avoided more reliably. Moreover, the designability can also be improved.

  Furthermore, by providing the constituent elements according to claim 3, microprojections 3 b, 3 c having a plurality of vertices per projection having excellent mechanical strength as compared with microprojections 3 a having one vertex per projection,... By providing an external force, it is possible to prevent the microprojections 3 from being damaged as compared with the case of only the microprojections 3a having one apex per projection, thereby preventing the antireflection function. It is possible to reduce local deterioration of the image and further reduce the appearance defects. Also, even if the microprojection 3 is damaged, the area of the damaged portion can be reduced, which can also reduce local deterioration of the antireflection function and further reduce the occurrence of appearance defects.

  Furthermore, by providing the structural requirements described in claim 4, it is possible to achieve both transparency (lighting property) and antireflection function, transparency improvement of the transparent body 1 (prevention of collision) and maintenance of privacy, and design. It can be a joinery with excellent properties.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram (plan view) which shows the transparent body of the 1st form which is one Embodiment of this invention. It is sectional drawing which follows the XX line of FIG. It is a schematic diagram (plan view) which shows the transparent body of the 2nd form which is one Embodiment of this invention. It is sectional drawing which follows the YY line of FIG. It is a schematic diagram of the glass door (joint) which is one Embodiment of this invention. It is a schematic diagram of the showcase which is one Embodiment of this invention. It is a schematic diagram of the aluminum sash window which is one Embodiment of this invention. It is a figure where it uses for description of an adjacent protrusion. It is a figure where it uses for description of the maximum point. It is a figure which shows a Delaunay figure. It is a frequency distribution diagram used for the measurement of the distance between adjacent protrusions. It is a frequency distribution diagram used for description of minute height. It is a figure with which it uses for description of a microprotrusion. It is a photograph of a microprotrusion. It is a conceptual sectional view showing the form in which the envelope surface of the valley bottom of the microprojection exhibits an uneven surface (waviness). It is a figure which shows the example of frequency distribution of the height h of the microprotrusion formed in the formation area of a transparent body. It is a figure which shows the preparation process of a roll plate. It is a schematic diagram which shows the micropore produced by the anodic oxidation process and etching process in the manufacturing process of the shaping mold. It is a figure which shows the frequency distribution of the height h of the microprotrusion formed in the formation area of the transparent body of an Example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present invention.

  First, FIG. 1 to FIG. 4 illustrate two forms of the transparent body 1 according to this embodiment. The transparent body 1 is made of a transparent substrate 2 and has an antireflection microprotrusion 3 (hereinafter simply referred to as “microprotrusion” or “protrusion”) on one surface 2s thereof. In this case, an antireflection microprojection formation region 4 (hereinafter simply referred to as “formation region 4”) and an antireflection microprojection composed of “microprojection group” or “projection group”. A non-formation region 5 (hereinafter simply referred to as “non-formation region 5”) is formed. The transparent body 1 is typically used as a translucent member such as a glass plate in a window glass, a glass door, a show window, a show case, or the like.

  In the present invention, the transparent body 1 is the formation of antireflection microprotrusions on at least a part of the surface of a solid transparent substrate 2 that transmits light, particularly light having a wavelength in the visible light region (380 nm or more and 780 nm or less). The region 4 is formed.

  As shown in FIG. 1 and FIG. 2, non-formation is achieved by providing both the antireflection small projection formation region 4 and the antireflection microprojection non-formation region 5 on one surface 2 s of the transparent substrate 2. In the region 5, reflection of sunlight and electric light and reflection of scenery occur, and the formation region 4 becomes the transparent body 1 in which these reflection and reflection hardly occur.

  From the viewpoint of improving the visibility of the transparent body 1 or preventing the collision, the difference in reflection and reflection is recognized and the presence of the transparent body 1 is recognized. Therefore, in order to improve the visibility of the presence of the transparent body 1 or prevent collision, the boundary area between the antireflection microprojection formation region 4 and the antireflection microprojection non-formation region 5 is: It is preferable that it is formed at a position that is conspicuous visually.

  In the present invention, the microprotrusions 3 are closely arranged, and the interval between the adjacent microprotrusions 3 is a region where the microprojections are formed, which is equal to or less than the shortest wavelength of the wavelength band of the electromagnetic wave to prevent reflection. The formation region 4 has a very low reflectance of usually 1% or less, and in many cases 0.1% or less. Further, since the reflection hardly occurs, the boundary with the non-formation region 5 can be recognized more clearly. .

  From the viewpoint of improving the visibility of the transparent body 1 or preventing collision, for example, the antireflection microprojection formation region 4 and the antireflection microprojection non-formation region 5 are formed only on one surface 2s. In some cases, the visibility from the formed surface is higher, and the visibility is higher when viewed from a brighter side (irradiated with light). Further, as shown in FIGS. 3 and 4, the antireflection microprojection formation region 4 and the antireflection microprojection non-formation region are formed on both the one surface 2 s and the other surface 2 r of the transparent substrate 2, respectively. 5 is formed so that the formation region 4 formed on one surface and the formation region 4 formed on the other surface coincide with each other in the normal direction of the transparent substrate 2. The formation region 4 does not cause reflection or reflection that occurs on both surfaces of the transparent base material 2, so the presence is weakened, but the difference from the non-formation region 5 becomes more clear, so that the visibility is further improved. Can be improved.

  Further, the boundary between the antireflection microprojection formation region 4 and the antireflection microprojection non-formation region 5 is more conspicuous if it is a complex shape than a simple band, and enters the line of sight rather than being uniformly present throughout. It is more effective to concentrate on easy-to-use parts. Anti-collision design on human eyes or children's eyes (Hitgata (doll) warning figure or “caution” or “danger” logo) or clear pattern (cross line, wavy line) It is effective to arrange it in Although it is transparent, it can be easily perceived as something is present, and collision can be effectively avoided. If you want to focus on design, you can use a store logo, anagram, trademark, or pattern.

  In the case of a window or the like for observing a night view or a landscape, if the formation of the antireflection microprojection formation region 4 and the antireflection microprojection non-formation region 5 is limited to the indoor side, the interior of the window It becomes a window having both easy observation and visibility, and the interface on the outdoor side of the transparent body 1 is reflected and reflected, making it difficult to observe the room from the outside. Of course, the visibility is also improved.

  In the case of an application in which the room from the outside may be visible, an antireflection microprojection formation region 4 and an antireflection microprojection non-formation region 5 are formed on both surfaces 2s and 2r of the transparent substrate 2, respectively. The formation region 4 formed on one surface 2s and the formation region 4 formed on the other surface 2r are provided so as to coincide with each other in the normal direction of the transparent substrate 2 (FIG. 3, 4), it is possible to realize a window that is easy to observe from the inside and from the outside and has a better visibility.

  In any case, even if the room is bright, there are no reflections or reflections on the windows, so you can enjoy the outdoors and the night view comfortably. In particular, when viewing a night view, it is not necessary to darken the room, and it is possible to view the night view comfortably while having a meal under bright lighting. However, the illumination light is several percent on the surface of the non-reflective microprojection formation region 5 (in the case of a glass plate having a refractive index of about 1.5, 4% on one surface with respect to the incident light from the normal direction). Since both surfaces are reflected (approx. 8% in total) and the indoor scene is reflected, the presence of the window can be visually recognized and collision with the window or door can be prevented.

In the case of an application that achieves both improved daylighting and privacy protection, the portion of the transparent substrate 2 that is easily peeped or the portion that is not desired to be peeped is designated as the non-reflective microprojection non-formation region 5 and importance is placed on daylighting. This can be realized by forming both regions as the antireflection minute projection forming region 4 in a part.
For example, when the transparent body 1 is applied to a window glass or the like, a portion having a height of 80 cm to 180 cm in the vertical direction from the outside ground that is easy for a person to peep is used as the non-reflective microprojection formation region 5 for comparison. This can be realized by forming a portion having a height of 80 cm or less in the vertical direction from the outside ground, which is difficult to look into, or a portion higher than 180 cm, as the formation region 4 of the antireflection microprotrusions. (Fig. 7)

<Transparent substrate>
Various materials can be used for the transparent substrate 2 used in the invention of the present application, but it is necessary to be a material that transmits at least part of light in the visible light wavelength range (380 nm to 780 nm). Preferably, the present invention can be effectively applied to any material having a high transmittance over the entire wavelength in the visible light region. In addition, when used in daylighting applications, it is possible to expect an increase in room temperature as well as brightness as long as the material has transmittance even for light having a wavelength in the infrared region. In the case of an application using ultraviolet rays such as a window of a room for sunbathing, a greenhouse or an agricultural greenhouse, a material having transparency also in the ultraviolet region is selected. In applications such as a show window, a showcase, or a window for viewing scenery, it is preferable that the transmittance is as high as possible in the entire wavelength range of the visible light region, because it is possible to appreciate without a sense of incongruity.

  Here, examples of the material of the transparent substrate 2 include cellulose resins such as TAC (Triacetyl cellulose), acrylic resins such as PMMA (polymethyl methacrylate), and polyesters such as PET (Polyethylene terephthalate). In addition to various transparent resin films such as plastic resins, polyolefin resins such as PP (Poly (propene)), vinyl resins such as PVC (Polyvinyl chloride), PC (Polycarbonate), etc., for example, soda glass, potassium glass, lead glass Various transparent inorganic materials such as glass such as PLZT, ceramics such as PLZT, quartz, and meteorite can be applied.

<Micro projection>
In the present invention, the minute protrusions 3 formed on the transparent substrate 2 have an interval d between adjacent minute protrusions 3 as shown in FIG. 2, which is equal to or less than the shortest wavelength Λmin of the wavelength band of electromagnetic waves to prevent reflection (d ≦ (Λmin) are closely arranged. In this embodiment, since the formation of the microprojections 3 is mainly aimed at improving the observation through the transparent body 1 and the daylighting property, this shortest wavelength is in the visible light region taking into account individual differences and visual conditions. The shortest wavelength (380 nm) is set, and the interval d is set to 100 to 300 nm in consideration of variation. The adjacent minute protrusions 3 related to the distance d are so-called adjacent minute protrusions 3, and are protrusions that are in contact with the hem (or heel) portion of the minute protrusion 3 that is the base portion on the transparent substrate 2 side. . In the transparent body 1, the microprojections 3 are closely arranged so that when a virtual line segment is created so as to sequentially follow the valleys between the microprojections 3, the polygons surrounding each microprojection 3 in a plan view. A mesh-like pattern formed by connecting a large number of shape regions is produced. The adjacent minute protrusions 3 related to the distance d are protrusions that share a part of the line segments constituting the mesh pattern.

  The minute protrusion 3 is defined in more detail as follows. In the antireflection by the moth-eye structure, the effective refractive index at the interface between the surface of the transparent body 1 and the medium adjacent thereto is continuously changed in the thickness direction to prevent the reflection. It is necessary to satisfy certain conditions. Among these conditions, important ones are the protrusion interval d and the protrusion height H. With respect to this one protrusion interval d, when the minute protrusions 3 are regularly arranged at a constant period as disclosed in, for example, Japanese Patent Application Laid-Open No. 50-70040, Japanese Patent No. 4632589, etc., adjacent minute protrusions The interval d of 3 is the protrusion arrangement period P (d = P). As a result, when the longest wavelength in the visible light band is λmax, the shortest wavelength in the visible light region is λmin, and the shortest wavelength in the wavelength band of light to be anti-reflected is Λmin, antireflection is performed at the longest wavelength in the visible light band. Since the minimum necessary condition that can produce the effect is Λmin = λmax, P (= d) ≦ λmax, and it is necessary to exhibit the antireflection effect for all wavelengths in the visible light band (λmin ≦ λ ≦ λmax). A sufficient condition is Λmin = λmin, and therefore P (= d) ≦ λmin.

  The wavelengths λmax and λmin may have some width depending on observation conditions, light intensity (luminance), individual differences, and the like, but are typically λmax = 780 nm and λmin = 380 nm. Preferable conditions for more reliably exhibiting the antireflection effect for all wavelengths in the visible light band are P (= d) ≦ 300 nm, and more preferable conditions are P ≦ 200 nm. Note that the lower limit value of the period P is normally set to P ≧ 50 nm, preferably P ≧ 100 nm, for reasons such as the expression of the antireflection effect and the securing of isotropicity (low angle dependency) of the reflectance. Further, in order to reduce white turbidity when viewed from an oblique direction (a direction of 45 degrees or more from the normal direction of the transparent substrate), P ≧ 150 nm is preferable, and P ≧ 200 nm is more preferable. On the other hand, the height H of the protrusion is set to H ≧ 0.2 × λmax = 156 nm (assuming λmax = 780 nm) from the viewpoint of exhibiting a sufficient antireflection effect.

  However, when the microprotrusions 3 are irregularly arranged as in the present embodiment, the distance d between the adjacent microprotrusions 3 varies. More specifically, as shown in FIG. 8, when viewed from the normal direction of the front surface or the back surface of the transparent substrate 2, when the microprojections 3 are not regularly arranged at a constant period, Depending on the repetition period P, the distance d between adjacent protrusions cannot be defined, and even the concept of adjacent protrusions may cause doubt. In addition, when a predetermined number of distances between the microprojections 4 are simply measured and the maximum value is adopted as the maximum interprotrusion distance, an abnormal value that does not reflect the actual interprotrusion distance due to scratches, foreign matter, etc. is adopted. There is also a risk of doing. Therefore, in such a case, it is calculated as follows.

  (1) That is, first, an in-plane arrangement of projections (plane of projection arrangement) using an atomic force microscope (referred to as AFM) or a scanning electron microscope (referred to as SEM). Visual shape) is detected. FIG. 8 is an enlarged photograph in which the height information of the microprojections 3 actually obtained by an atomic force microscope is converted into image data for the microprojections 3 in the transparent body 1 of the present embodiment. In addition, the transparent body 1 of this embodiment which has the microprotrusions 3 on the surface as shown in FIG. 8 is 0.05 with respect to visible light in a wavelength range of 380 to 780 nm incident from the normal direction of the transparent substrate 2. Has a reflectance of ˜0.1%.

  (2) Subsequently, the maximum point of the height of each protrusion (hereinafter simply referred to as the maximum point) is detected from the obtained in-plane arrangement. The maximum point means a point where the height is larger (maximum value) than any point around the vicinity. The maximum point corresponds to the apex of the minute protrusion 3. In addition, as a method for obtaining the local maximum point, a method for obtaining the local maximum point by sequentially comparing the planar view shape and the enlarged photograph of the corresponding cross-sectional shape, and the local maximum point by image processing of the planar view enlarged photograph obtained by imaging the height data. Various methods such as a method for obtaining, and direct analysis of the height data of the microprojections 3 obtained from the AFM can be applied. FIG. 9 is a diagram illustrating a detection result of a local maximum point by processing data related to in-plane distribution data of height corresponding to an enlarged photograph obtained by imaging the height data illustrated in FIG. In this figure, each point indicated by a black dot is a maximum point of each protrusion. In this process, the height data is processed in advance by a low-pass filter having a Gaussian characteristic of 4.5 × 4.5 pixels, thereby preventing erroneous detection of the maximum point due to noise. Further, a maximum point was obtained in units of 1 nm (= 1 pixel) by sequentially scanning a filter for detecting a maximum value of 8 pixels × 8 pixels.

  (3) Next, a Delaunay diagram with the detected maximum point as a generating point is created. Here, Delaunay diagram is obtained by dividing the Voronoi region adjacent to the Voronoi region when the Voronoi division is performed with each local maximum as the generating point, and connecting the adjacent generating points with line segments. This is a net-like figure made up of triangular aggregates. Each triangle is called a Delaunay triangle, and each triangle side (line segment connecting adjacent generating points) is called a Delaunay line. FIG. 10 is a diagram in which the Delaunay diagram (represented by white line segments) obtained from FIG. 9 is superimposed on the original image of FIG. The Delaunay diagram has a dual relationship with the Voronoi diagram. Voronoi division means that a plane is divided by a net-like figure composed of a set of closed polygons defined by vertical bisectors of line segments (Droney lines) connecting between adjacent generating points. A network figure obtained by Voronoi division is a Voronoi diagram, and each closed region is a Voronoi region.

(4) Next, the frequency distribution of the length of each Delaunay line, that is, the distance between adjacent maximum points, is regarded as the distance between adjacent protrusions, and the distance (hereinafter referred to as the distance between adjacent protrusions). Find the frequency distribution of. FIG. 11 is a histogram of the frequency distribution created from the Delaunay diagram of FIG. As shown in FIG. 8 and FIG. 13, when there is a groove-like recess at the top of the projection, or the top is split into a plurality of peaks, the top of such a projection is obtained from the obtained frequency distribution. The data resulting from the fine structure in which the concave portion is present and the fine structure in which the top portion is split into a plurality of peaks are removed, and only the data of the projection body itself is selected to create a frequency distribution.
In addition, the microprotrusion in which the top part is divided into a plurality of peaks and has a plurality of vertices per protrusion is referred to as a multimodal microprotrusion. A microprojection having only one vertex per projection (having only one peak) is referred to as a monomodal microprojection.

  Specifically, in the fine structure in which the concave portion is present at the top of the protrusion, or the fine structure related to the multimodal microprotrusions 3b, 3c,. From the numerical range in the case of the unimodal microprotrusions 3a that are not provided, the distance between adjacent local maximum points is clearly different. Thus, by removing the corresponding data using this feature, only the data of the projection body itself is selected and the frequency distribution is detected. More specifically, for example, about 5 to 20 adjacent single-peak microprojections 3a are selected from an enlarged photograph of the microprojections (group) in plan view as shown in FIG. Sampling the distance value, and a value that clearly deviates from the numerical range obtained by sampling (usually the value for the average distance between adjacent maximum points obtained by sampling only single-peak microprojections) Is excluded, and the frequency distribution is detected. In the example of FIG. 11, data having a distance between adjacent maximum points of 56 nm or less (the leftmost small mountain indicated by the arrow A) is excluded. FIG. 11 shows a frequency distribution before such exclusion processing is performed. Incidentally, such exclusion processing may be executed by setting the above-described maximum point detection filter.

(5) The average value d _AVG and the standard deviation σ are obtained from the frequency distribution of the distance d between adjacent protrusions thus obtained. When the frequency distribution obtained in this way is regarded as a normal distribution and the average value d _AVG and the standard deviation σ are obtained, the average value d _AVG = 158 nm and the standard deviation σ = 38 nm are obtained in the example of FIG. Thus, the maximum value of the distance d between adjacent protrusions is set to dmax = d _AVG + 2σ, and in this example, dmax = 234 nm.

The same method is applied to define the height of the protrusion. In this case, a relative height difference of each local maximum point position from a specific reference position is acquired from the local maximum point obtained by the above (2), and is histogrammed. FIG. 12 is a diagram showing a histogram of the frequency distribution of the protrusion height H with the protrusion root position thus obtained as a reference (height 0). The average protrusion height H _AVG and standard deviation σ are obtained from the frequency distribution based on this histogram. Here, in the example of FIG. 12, the average protrusion height H _AVG = 178 nm and the standard deviation σ = 30 nm. Accordingly, in this example, the height of the protrusion is the average protrusion height H _AVG = 178 nm. In the histogram of the protrusion height H shown in FIG. 12, in the case of the multi-peak microprotrusions 3b, 3c,... The protrusion height data will be mixed. Therefore, in this case, the frequency distribution is obtained by adopting the vertex having the highest height from among the plurality of vertices belonging to the same microprotrusion as the protuberance. In addition, when the minute protrusions having the same collar portion have a plurality of vertices and the heights of all the vertices are the same, the height of the minute protrusion is defined as the common protrusion height.

In addition, the reference position when measuring the height of the projection described above is based on the valley bottom (minimum point of height) between the adjacent minute projections 3 as a reference of height 0. However, when the height of the valley bottom itself varies depending on the location (for example, as described later with reference to FIG. 15, the height of the valley bottom has undulation with a period larger than the distance between adjacent projections of the microprojections 3). When the fluctuation range of the height of the valley bottom is sufficiently smaller than the height of each protrusion, specifically, the standard deviation in the height distribution of the valley bottom obtained by sampling 5 to 20 minute protrusions. Is σ, and the average value of the height h from the adjacent valley bottom of each microprojection 3 is h _AVG .
4σ ≦ 0.1h _AVG
In the case of (1), the height of the microprojection is calculated as follows (1) to (3). (1) First, an average value of the heights of the valley bottoms measured from the front surface or the back surface of the transparent substrate 2 is calculated within an area sufficient for the average value to converge. (2) Next, a plane having the average height and parallel to the front or back surface of the transparent substrate 2 is considered as a reference plane. (3) Then, the height of each microprotrusion from the reference surface is calculated by setting the reference surface to a height of 0 again.

In addition, as in the modification shown in FIG. 15, when the fluctuation range of the height of the valley bottom is sufficiently larger than the height of each protrusion, specifically, when the standard deviation σ of the height distribution of the valley bottom is used,
4σ> 0.1h _AVG
In the case of (1), the height of the microprojection is calculated as follows (1) to (3). In this case, the protrusion height is calculated as follows. (1) The envelope surface 16 which connects the position of each valley bottom, that is, the minimum point of each height, is obtained. (2) Next, the height of the minute projection is calculated by setting the height of the envelope surface 16 immediately below the center of each projection to height = 0.

When the protrusions are irregularly arranged, the maximum value dmax = d _AVG + 2σ of the distance between adjacent protrusions thus obtained and the average protrusion height H _AVG described above in the case where the protrusions are regularly arranged. It was found necessary to satisfy the conditions. Specifically, the condition of the distance between the microprotrusions that exhibits the antireflection effect is dmax ≦ Λmin. The minimum necessary condition that can exhibit the antireflection effect at the longest wavelength in the visible light band is Λmin = λmax, and therefore dmax ≦ λmax, and the antireflection effect can be obtained for all wavelengths in the visible light band. The necessary and sufficient condition is Λmin = λmin, and therefore dmax ≦ λmin. A preferable condition that can more reliably exhibit the antireflection effect for all wavelengths in the visible light band is dmax ≦ 300 nm, and a more preferable condition is dmax ≦ 200 nm. Also, dmax ≧ 50 nm is usually satisfied and dmax ≧ 100 nm is preferable because of the antireflection effect and ensuring the isotropic (low angle dependency) of the reflectance. The height of the protrusion is set to H _AVG ≧ 0.2 × λmax = 156 nm (assuming λmax = 780 nm) in order to exhibit a sufficient antireflection effect.

8 to 12, dmax = 234 nm ≦ λmax = 780 nm, and it can be seen that the antireflection effect can be sufficiently achieved by satisfying the condition of dmax ≦ λmax. In addition, since the shortest wavelength λmin in the visible light band is 380 nm, it can be seen that the sufficient condition dmax ≦ λmin for exhibiting the antireflection effect in all visible light wavelength bands is also satisfied. Further, since the average protrusion height H _AVG = 178 nm, the average protrusion height H _AVG ≧ 0.2 × λmax = 156 nm (assuming the longest wavelength λmax = 780 nm of the visible light wavelength band), and a sufficient antireflection effect is realized. It can be seen that the conditions regarding the height of the protrusions to satisfy are also satisfied. Since the standard deviation σ = 30 nm, the relational expression H _AVG −σ = 148 nm <0.2 × λmax = 156 nm is established, and therefore, statistically, 50% or more and 84% or less of all the protrusions. It can be seen that the condition of the height of the protrusion (178 nm or more) is satisfied. From the observation results by AFM and SEM and the analysis result of the height distribution of the microprojections, the multi-peak microprojections 3b, 3c,... Are microprojections having a height higher than the microprojections having a relatively low height. It tends to occur more.

  As in this embodiment, when the monomodal microprotrusions 3a and the multimodal microprotrusions 3b, 3c,... Are mixed, the monomodal microprotrusions 3a having different aspect ratios are mixed. Similarly, a low reflectance can be secured in a wide wavelength band.

  That is, when producing micropores by anodic oxidation, the pitch and depth of the micropores are proportional. Thus, a mold for molding is produced by repeating the anodizing treatment and the etching treatment, and is produced when the microprojections 3 are produced on the transparent substrate 2 by the molding process using the mold for molding. The monomodal microprotrusions 3a are held substantially constant in aspect ratio, which is the ratio between the width and height of the base portion.

  The antireflection function of the formation region 4 of the transparent body 1 depends not only on the interval between the minute protrusions but also on the aspect ratio. When the aspect ratio is constant, for example, a sufficiently small reflectance can be secured in the visible light region. However, in the ultraviolet region, the reflectance increases compared to the visible light region and the antireflection function is insufficient. If the pitch of the minute protrusions is further reduced so that a sufficient antireflection function can be ensured in the ultraviolet region, the antireflection function is lowered in the infrared region.

  However, in the multimodal microprotrusions 3b, 3c,..., It is possible to ensure an antireflection function by reducing the interval between adjacent protrusions. A low reflectance can be secured in a wide wavelength band. In the case where a sufficiently small reflectance is ensured in a wide wavelength band centered on the visible light region, the multi-protrusion is small in the minute protrusions due to the distance between adjacent protrusions of 480 to 660 nm corresponding to the wavelength 480 to 660 nm in the visible light region. It is desirable to mix the microprotrusions 3b, 3c,... And the single-peak microprotrusions 3a.

Here, the multimodal microprotrusions 3b, 3c,... Formed in the formation region 4 of the transparent body 1 improve the antireflection function for the incident light in the visible light region and the scratch resistance of the microprotrusions. In order to achieve this, it must be formed so as to satisfy the following conditions. FIG. 16 is a diagram illustrating an example of the frequency distribution of the height h of the fine protrusions formed in the formation region 4 of the transparent body 1. As shown in FIG. 16, the average value of the height in the frequency distribution of the height h of the microprojections is m, the standard deviation is σ, the region of h <m−σ is the low altitude region of the microprojections, and m− When the region of σ ≦ h ≦ m + σ is a medium altitude region and the region of m + σ <h is a high altitude region, the number Nm of the multimodal microprojections 3b, 3c,. The ratio with the total number Nt of microprojections in the whole needs to satisfy the following relationships (a) and (b).
(A) Nm / Nt in the middle altitude region> Nm / Nt in the low altitude region
(B) Nm / Nt in middle altitude region> Nm / Nt in high altitude region

<Formation area of antireflection micro-projections>
In the present invention, the antireflective microprojection formation region 4 is a region where the antireflective microprojection 3 is formed as described above, and is a part of the surface 2s of the transparent substrate or the total area of 2s and 2r. Thus, it is formed in a region where priority is given to transparency, daylighting, reflection prevention, and reflection prevention. The present formation region 4 alone has high effects such as transparency, daylighting, reflection prevention, and reflection prevention, but is disadvantageous in terms of the visibility of the transparent body 1, privacy protection, and peep prevention effects.

  The antireflection microprojection formation region 4 may be formed integrally with the transparent substrate 2 by shaping the microprojections 3 on the surface 2s or 2s and 2r of the transparent substrate 2, or the transparent substrate 2 A layer (receiving layer 14) formed by forming the fine protrusions 3 on the surface of the material 2 may be directly laminated. Moreover, you may form by bonding the base base material in which the anti-reflective microprotrusion 3 was formed, and the transparent base material 2 together.

<Non-formation area of microprojections>
In the present invention, the microprojection non-formation region 5 is a region in which the microprojection 3 is not formed. From the viewpoint of transparency, daylighting property, antireflection property, daylighting property, and antireflection effect, the antireflection microprojection region is used. The formation region 4 is inferior to the formation region 4 of the anti-reflective microprojections in terms of the effect of protecting privacy and preventing peeping. Can be improved.

  In the present invention, the non-reflective micro-projection non-formation region 5 is a region where the micro-projections 3 are not formed, but as a result, the micro-projections are not formed. That is, the antireflection microprotrusions 3 may be provided once adjacent to each other on the entire surface, and the microprojections 3 that are desired to be the antireflection microprotrusions non-formation region 5 may be peeled, removed, or destroyed. The surface of the microprojections 3 may be smoothed by covering the microprojections 3 with a material having a refractive index close to that of the microprojections 3. In particular, after forming the antireflective microprotrusions 3 on the entire surface of the transparent body 1, the ultraviolet curable resin used for forming the microprotrusions 3 by screen printing is filled and applied in a place where the microprotrusions non-formation regions 5 are to be formed. Even if the pattern is complicated or fine, it can be efficiently created.

  Alternatively, it is formed by forming the antireflection microprojections 3 only on the surface 2 s on the transparent substrate 2, or only on the portions other than the antireflection microprojection non-formation regions 5 of 2 s and 2 r, or antireflection The base substrate on which the fine protrusions 3 are formed in advance may be affixed except for the non-formation region 5 of the minute protrusions. These methods are easy to use in privacy protection applications in which a microprojection formation region 4 and a microprotrusion non-formation region 5 are formed in a relatively large area.

  Alternatively, by forming the anti-reflective micro-projections 3 on the entire surface of the transparent body 1 and then melting or burning the micro-projections 3 with leather, even a complicated or fine pattern can be efficiently created. It becomes.

<Manufacturing method of antireflection microprotrusions>
In the manufacturing method of the antireflection microprotrusion 3 having the shape as described above, a photoresist or the like is applied to the surface on which the antireflection microprotrusion 3 is formed, and the planar shape of the microprotrusion 3 is formed. A pattern is directly exposed on the surface of the optical component by producing a resist pattern by exposing and developing the pattern, and corroding the glass substrate with the pattern. Various methods have been proposed, such as those described in Japanese Patent No. 50-70040.

  In the present invention, although not particularly limited, anodization and etching are performed on an aluminum plate from the viewpoint that it can be produced by mixing single-peak microprojections 3a and multi-peak microprojections 3b, 3c,. A method for forming a mold for shaping is suitable.

  Hereinafter, typical embodiments of the manufacturing method of the present invention will be described. In this manufacturing process, in the resin supplying process, an uncured and liquid ultraviolet curable resin that forms a microprojection-shaped receiving layer is applied to a base substrate in the form of a strip-shaped film by a die. In addition, about application | coating of ultraviolet curable resin, not only the case of using a die | dye but various methods are applicable. Subsequently, in this manufacturing process, the base substrate is pressed and pressed against the peripheral side surface of the roll plate, which is a mold for molding the fine protrusions 3, by the pressing roller. The acrylate-based ultraviolet curable resin is brought into close contact, and the fine concavo-convex recesses formed on the peripheral side surface of the roll plate are sufficiently filled with the ultraviolet curable resin. In this state, in this manufacturing process, the ultraviolet curable resin is cured by irradiation with ultraviolet rays, thereby producing a group of minute protrusions on the surface of the base substrate. In this manufacturing process, the base substrate is subsequently peeled off from the roll plate integrally with the cured ultraviolet curable resin via a peeling roller. In the manufacturing process, an adhesive layer or the like is formed on the surface of the base substrate opposite to the surface on which the microprojections are formed, and then cut into a desired shape and size and bonded to the transparent substrate 2. The transparent body 1 is produced. Thus, the transparent body 1 can be efficiently mass-produced by sequentially molding the fine shape produced on the peripheral side surface of the roll plate, which is a mold for molding, on a long base substrate made of a roll material. it can.

  The roll plate has a fine uneven shape in which a large number of small holes are arranged on the peripheral side surface of the base material, which is a cylindrical metal material, by repeating anodizing treatment and etching treatment. As such, it is molded into the substrate. For this reason, a columnar or cylindrical member in which a high-purity aluminum layer is provided at least on the peripheral side surface is used as the base material. More specifically, in this embodiment, a hollow stainless steel pipe is applied to the base material, and a high-purity aluminum layer is provided directly or via various intermediate layers. The purity of aluminum is 99.0% or higher, and usually 99.9% or higher. In addition, it may replace with a stainless steel pipe and may apply pipe materials, such as copper and aluminum. By repeating the anodizing treatment and the etching treatment, the roll plate has fine holes formed densely on the peripheral side surface of the base material, and the fine holes are dug and the diameter of the roll plate becomes larger as it approaches the opening. The concavo-convex shape is produced by gradually increasing the hole diameter of the fine holes. As a result, the roll plate has densely formed micropores whose pore diameter gradually decreases in the depth direction, and the transparent body 1 has a large number of gradually decreasing diameters as it approaches the top corresponding to the micropores. A minute uneven shape is produced by the minute protrusion 3. At that time, by appropriately adjusting various conditions such as the purity (impurity amount), crystal grain size, anodizing treatment and / or etching treatment of the aluminum layer, the shape of the fine protrusion unique to the present invention is obtained.

[Anodic oxidation treatment, etching treatment]
FIG. 17 is a diagram showing a roll plate manufacturing process. In this manufacturing process, the peripheral side surface of the base material is made into a super mirror surface by an electrolytic composite polishing method that combines electrolytic elution action and abrasion action by abrasive grains (electrolytic polishing). In the subsequent step, aluminum is sputtered on the peripheral side surface of the base material to produce a high-purity aluminum layer (aluminum layer forming step). In the subsequent process, the process of anodizing, that is, the process of anodizing A1,..., AN, the process of performing etching, that is, the etching process E1,. A roll plate is produced. Note that the number N (integer of 2 or more) of the anodizing step and the etching step is usually 2 to 7.

  In this manufacturing process, in the anodic oxidation steps A1,..., AN, fine holes are produced on the peripheral side surface of the base material by an anodic oxidation method, and the produced fine holes are further dug. Here, in the anodizing step A1,..., AN, various methods applied to aluminum anodizing can be widely applied, for example, when a carbon rod, a stainless steel plate, or the like is used for the negative electrode. Further, as the solution, various neutral and acid solutions can be used. More specifically, for example, a sulfuric acid aqueous solution, an oxalic acid aqueous solution, a phosphoric acid aqueous solution and the like can be used. In this manufacturing process A1,..., AN, the fine holes are formed into shapes corresponding to the target depth and the shape of the fine protrusions, respectively, by managing the liquid temperature, bath concentration, applied voltage, time for anodic oxidation, etc. To do.

  In the subsequent etching process E1,..., EN, the mold is immersed in an etching solution, and the diameter of the fine holes produced and dug in the previous anodic oxidation process A1,. These fine holes are formed so that the hole diameter becomes smoother and gradually smaller. As the etching solution, various etching solutions that are applied to this type of treatment can be widely applied. More specifically, for example, a sulfuric acid aqueous solution, an oxalic acid aqueous solution, a phosphoric acid aqueous solution, or the like can be used. By using the same solution as the solution used for the anodizing treatment without applying a voltage, the solution can be used also as an etching solution. As a result, in this manufacturing process, the anodizing process and the etching process are alternately performed a plurality of times, thereby forming micropores for shaping on the peripheral side surface of the base material.

[Formation process of micropores forming microprotrusions]
Next, a method for forming the multimodal microprotrusions 3b, 3c,... And forming fine holes in which the height distribution of the microprotrusions is controlled will be described. As described above, the fine holes formed in the shaping mold (roll plate) are formed by alternately repeating the anodizing treatment and the etching treatment, and the applied voltage in the repeated anodizing treatment is varied. As a result, the depth of the fine holes (the height distribution of the fine protrusions) can be controlled. Here, since the applied voltage in the anodizing treatment and the interval (pitch) between the formed fine holes are in a proportional relationship, each step A1,..., AN in the repetition of the anodizing treatment and the etching treatment. If the applied voltage of the anodic oxidation treatment is varied every time, it is possible to control the ratio by mixing micropores having different digging times in the depth direction. Or it is set as the fluctuation voltage which added the alternating voltage to the direct-current voltage. For example, the applied voltage can be anodized in each step as a voltage between 15 and 35V.

  In addition, in the case where the applied voltage in the anodic oxidation process is varied in this way, a plurality of micro holes are created on the bottom surface of the micro hole having a large thickness to form a micro hole related to the multimodal micro protrusion. Can do. The height distribution of the multimodal microprotrusions can be controlled by controlling the height of the thick micropores.

FIG. 18 is a schematic diagram for explaining the control of such a height distribution, and is a diagram showing fine holes produced by an anodizing step and an etching step in a molding die manufacturing process.
As described above, the relationship between the applied voltage in the anodic oxidation process and the pitch of the fine holes is proportional, but in practice, the pitch of the fine holes varies depending on the grain boundaries of aluminum used for the treatment. However, in FIG. 18, it is assumed that the micropores are formed in a regular arrangement, assuming that this variation does not exist. In FIGS. 18A to 18E, the left diagram shows an enlarged view of the surface of the roll plate, and the right diagram shows an aa cross-sectional view in the left diagram.

(First step)
As shown in FIG. 18 (a), first, after applying the voltage V1 to the aluminum layer on the surface of the shaping mold and performing the anodic oxidation step A1, the etching step E1 is carried out to form the fine holes f1. Form. Here, the anodic oxidation step A1 is to create a trigger for the anodic oxidation treatment that follows the flat surface of aluminum. In this case, the etching process may be omitted as appropriate.

(Second Step) Next, after applying the voltage V2 (V2> V1) higher than the voltage V1 to execute the anodic oxidation step A2, the etching step E2 is executed. As a result, in the anodizing step A2, as shown in FIG. 18B, among the fine holes f1 formed in the previous anodizing step A1, the fine holes f1 having an interval corresponding to the anodizing step A2 are further dug down. . In the present embodiment, the applied voltage V2 is set to V2 = 3 × V1, and the process of digging every two fine holes f1 formed in the previous anodizing process A1 is performed by the anodizing process A2. Therefore, every two large and deeply drilled fine holes f2 are formed on the surface of the mold for molding, and the surface of the roll plate is in a state where the fine holes f1 and f2 are mixed. .

(Third step)
Subsequently, after applying the voltage V3 (V3> V2) higher than the voltage V2 to execute the anodic oxidation step A3, the etching step E3 is executed. In this step, fine holes with different pitches are produced. Specifically, when the voltage to be applied is gradually increased from the voltage V2 to the voltage V3 and the increase in the applied voltage is executed discretely (stepwise), the height distribution of the microprojections (depth distribution of the micropores) ) Can be produced discretely, and when the applied voltage is continuously increased, the height distribution of the microprotrusions can be set to a normal distribution. Therefore, in the present embodiment, the applied voltage V3 is set to V3 = 4 × V1, and the application time of the applied voltage in the anodizing step A3 and the processing time of the etching step are compared with those in the first step and the second step described above. By setting the length too long, as shown in FIG. 18 (c), the fine holes f1 formed in the first anodizing step A1 are dug wide and deep so as to be combined into one, The bottom surfaces of the fine holes f3 collected into one are formed substantially flat (flat microhole forming step). Here, “substantially flat” means not only a state in which the bottom surface of the fine hole is flat but also a state in which the bottom surface is curved with a large curvature radius.

(Fourth process)
Subsequently, after applying the voltage V4 (V4> V3) higher than the voltage V3 to execute the anodic oxidation step A4, the etching step E4 is executed. In this step, micropores are created with a pitch based on the target interprotrusion spacing. Also in this anodizing step A4, the applied voltage is gradually increased from the voltage V3 to the voltage V4. In the present embodiment, the applied voltage V4 is set to V4 = 8 × V1, and as a result, a part of the fine hole f3 dug in the third step is further dug up. As a result, FIG. As shown to d), it becomes the micropore f4, and this micropore f4 forms the high monomodal microprotrusion 3a.

(Fifth step)
Subsequently, after changing the applied voltage to the voltage V1 in the first step and performing the anodic oxidation step A5, the etching step E5 is performed. In this process, the fine holes f1, f2, and f3 have the same number of holes at the bottom, and the number of holes in the hole shape remains unchanged. However, the fine holes formed in the anodizing process A3 are not changed. As shown in FIG. 18 (e), a plurality of fine holes are formed on the bottom surface of the fine hole f3 which is the hole f3 and is not affected by the anodic oxidation step A4 of the fourth step. Fine holes f5 corresponding to the fine protrusions 3b, 3c,... Are formed (micro-hole protrusion fine hole forming step). Here, by adjusting the magnitude of the voltage V1 to be applied, the number of micropores formed in the bottom surface of the micropore f5 can be increased or decreased, and the interval between the micropores can be adjusted.

  As described above, the microholes f1, f2, and f4 that form microprojections having different heights and the microholes f5 that form multimodal microprojections 3b, 3c,... It is formed. Here, in this series of steps, the fine holes f1 and f2 having different depths produced in the first step and the second step are dug in the third step to form a substantially flat fine hole f3 on the bottom surface. In the fourth step, the minute hole f3 is dug to produce the minute hole f4 related to the single-peaked minute projection 3a. In the fifth step, the bottom surface of the minute hole f3 is processed. The micropore f5 which concerns on the multimodal microprotrusion 3b, 3c, ... is produced. Here, by controlling the application time, the processing time, the processing time of the etching process, etc. of the anodizing process according to the first to fourth processes, the depth of the micropores produced in each process is controlled. Thus, the height distribution of the microprojections and the height distribution of the multimodal microprojections 3b, 3c,... Can be controlled. In addition, the above-mentioned 1st process-5th process can abbreviate | omit the number as needed, can repeat, or can integrate a process.

Next, an example of the antireflective microprotrusions 3 manufactured on the transparent body 1 by the molding die manufactured by the above-described method will be described.
〔Example〕
FIG. 19 is a diagram showing a frequency distribution of the height h of the antireflection microprotrusion 3 formed in the antireflection microprotrusion forming region 4 of the transparent body 1 of the present embodiment. The mold for manufacturing the microprojections 3 of the present embodiment is obtained by continuously changing the applied voltage of the anodizing process in the second step, the third step, and the fourth step. In the fourth step, the voltage is reduced from the applied voltage in the third step. In the formation region 4 manufactured by the mold for molding, the height distribution of the microprojections shows a normal distribution, and in a relatively narrow range centering on the normal of the surface on which the microprojections are formed, A good antireflection function can be ensured. Also, at this time, in such a height distribution, the multimodal microprojections (two and three vertices are indicated by two peaks and three peaks, respectively) also have a normal distribution in which the average values of the heights are almost the same. Thus, the scratch resistance function and the optical property improvement function of the multimodal microprotrusions 3b, 3c,... Can be efficiently exhibited.

In the formation region 4 of the example manufactured by the above-described method, as shown in FIG. 19, the average value of the heights of the microprojections is m = 145.7 nm, and the standard deviation is σ = 22.1 nm. .
Here, in the frequency distribution of the height h of the microprotrusions, the low altitude region is h <m−σ = 123.6 nm, and the middle altitude region is m−σ = 13.6 nm ≦ h ≦ m + σ = 167.8 nm. Thus, the high altitude region is h> m + σ = 167.8 nm.
The total number Nt of microprojections in the entire frequency distribution is 263. Further, since the number Nm of multi-modal microprotrusions in the middle altitude region is 23, Nm / Nt in the middle altitude region is 0.087. Since the number Nm of the multimodal microprotrusions in the low altitude region is two, Nm / Nt in the low altitude region is 0.008. Since the number Nm of multimodal microprojections in the high altitude region is 5, the Nm / Nt in the high altitude region is 0.019.

Therefore, the formation region 4 of this example has the above-described relationship (a) and (b), that is,
(A) Nm / Nt in the middle altitude region = 0.087> Nm / Nt = 0.008 in the low altitude region
(B) Nm / Nt = 0.087 in the medium altitude region> Nm / Nt = 0.19 in the high altitude region
Satisfied.

As described above, in the formation region 4 of the example, the ratio (Nm / Nt) between the number of multi-peak microprojections (Nm) in the medium altitude region and the total number of microprojections (Nt) in the frequency distribution is low Since the multimodal microprotrusions are formed so as to be larger than the ratio of the high altitude region, the reflectance for incident light in the visible light region can be effectively reduced, and the formation region 4 of the transparent body 1 can be reduced. It is possible to increase the bandwidth of the antireflection function.
In addition, the formation region 4 has an average value of almost the same height for the multi-peak microprojections (two and three vertices are indicated by two peaks and three peaks, respectively) in such a height distribution. Since the frequency distribution of the height H can be a matched normal distribution, the viewing angle characteristic is limited as compared with the case where the frequency distribution of the height H is closer to the uniform distribution than the normal distribution or has a plurality of maximum values of the frequency distribution, A sufficiently low reflectivity and a low haze are realized in the front direction where the angle with respect to the normal of the formation region 4 is 70 to 75 degrees or less, and the emissivity is obtained in the side direction where the angle with respect to the normal exceeds 70 to 75 degrees. It is possible to obtain a viewing angle characteristic in which prevention and haze rise. Due to such a limitation of viewing angle characteristics, it is observed as a part that does not cause good reflection or reflection with reduced external light reflection in the direction of the observer in fittings in the presence of external light. It is possible to expect the effect of being recognized as a part that is easily reflected and reflected visually due to an increase in reflectance and haze. In addition, the scratch resistance of the multimodal microprotrusions can be improved efficiently.
That is, with the above-described configuration, the formation region 4 has a small ratio of multi-peak microprojections distributed in microprojections having a high height (180 nm or more) and a large ratio of single-peak microprojections 3a. Even if another object comes into frictional contact with the microprotrusions, the high unimodal microprotrusions 3a come into contact first, and the multimodal microprotrusions 3b, 3c, which mainly improve the antireflection function.・ It is possible to suppress contact with.

  The characteristics of these multimodal microprotrusions 3b, 3c,... Are that of the multimodal microprotrusions 3b, 3c,. This is a unique feature and cannot be obtained by the multi-modal microprotrusions caused by the resin filling failure disclosed in Japanese Patent Application Laid-Open No. 2012-037670. That is, the multi-peak microprotrusions due to poor filling of the resin are produced by not sufficiently filling the micropores that are originally produced as the single-peak microprotrusions 3a. Therefore, it is difficult to sufficiently improve the scratch resistance, and it is also difficult to improve the optical characteristics as described above.

  Further, the multi-peak microprotrusions due to poor filling have a drawback that the reproducibility is poor, and this makes it impossible to mass-produce a uniform product. On the other hand, the multi-peak microprotrusions 3b, 3c according to this embodiment. ,... Can ensure high reproducibility by a so-called mold. Further, as described in detail for the above-described embodiment, the height distribution of the multimodal microprotrusions 3b, 3c,... It is difficult to control.

13 is a cross-sectional view (FIG. 13 (a)), a perspective view (FIG. 13 (b)), and a plan view (FIG. c)). Note that FIG. 13 is a diagram schematically showing for easy understanding, and FIG. 13A is a diagram showing a cross section by a broken line connecting the vertices of continuous microprotrusions. In FIGS. 13B and 13C, the XY direction is in the in-plane direction of the substrate 2, that is, one surface 2s of the transparent substrate 2, the other surface 2r, or a virtual plane parallel thereto. The Z direction is a direction perpendicular to the in-plane direction (XY plane or a direction parallel to the XY plane), that is, the height direction of the microprojections 3. In the transparent body 1, many microprotrusions 3 are gradually cut in a cross-sectional area (a plane perpendicular to the height direction (a plane parallel to the XY plane in FIG. 13)) toward the apex away from the transparent substrate 2. The cross-sectional area) is reduced, and one vertex is produced. However, in some cases, as if a plurality of microprotrusions 3 were combined, a groove g was formed at the tip, and the apex was two (3b), and the apex was three (3c) In addition, there are those having four or more vertices (FIG. 14C). The shape of the unimodal microprotrusions 3a can be approximated by a round shape at the top, such as a paraboloid of revolution, or a sharp shape at the apex, such as a cone. On the other hand, the shape of the multi-peak microprojections 3b, 3c,. The The shape of the multi-peak microprotrusions 3b, 3c,... Or the longitudinal cross-sectional shape when cutting along a virtual cut surface including a plurality of peaks and including the height direction (Z-axis direction in FIG. 13) is maximal. The shape is approximated by an algebraic curve Z = a ₂ X ² + a ₄ X ⁴ +... + A _2N X ^2N +. Here, N is a natural number.

The multi-peak microprotrusions 3b, 3c,... Having a plurality of such vertices are near the vertices even if the distance between the vertices correlated with the antireflection function is the same as that of the single-peak microprotrusions 3a. The thickness of the hem portion with respect to the dimension is relatively thick. Thus, it can be said that the multimodal microprotrusions 3b, 3c,... Exhibit the same antireflection performance as compared with the single-peak microprotrusions 3a, and have excellent mechanical strength. Thereby, when the multimodal microprotrusions 3b, 3c,... Having a plurality of vertices are present, the transparent body 1 is considered to have improved scratch resistance as compared with the case of using only the single-peak microprotrusions 3a. . Furthermore, when an external force is applied to the transparent body 1 specifically, since the external force is distributed and received at more vertices than when only the single-peaked microprojection 3a is received, the external force applied to each vertex is reduced. Thus, it is possible to make the microprotrusions less likely to be damaged, thereby reducing local deterioration of the antireflection function, and further reducing the appearance defects. Even if the microprojection 3 is damaged, the area of the damaged portion can be reduced. Moreover, multimodal microprojections 3b, 3c, many ..., highest peak height (foot height of the highest peaks belonging to the same microprojections) is to produce an average projection height H _AVG or more microprojections , Each ridge portion first receives external force and is sacrificially damaged, so that the body portion lower than the ridges of the microprojections and the microprojections with a lower height than the multimodal microprojections 3b, 3c,. Prevent wear and tear. This also reduces local deterioration of the antireflection function and further reduces the occurrence of appearance defects.

  The measurement results according to FIGS. 8 to 12 described above are the measurement results of the transparent body 1 according to this embodiment, and in the frequency distribution shown in d of FIG. 11, the distance d between adjacent protrusions (value on the horizontal axis). There are two types of local maximum values: short-range maximum values of 20 nm and 40 nm and long-range maximum values of 120 nm and 164 nm. Among these maximum values, the maximum value of the long distance corresponds to the arrangement of the microprojection bodies (the part from the middle to the heel below the top part), while the maximum value of the short distance exists in the vicinity of the top part. Corresponds to the apex (peak) of. Thereby, the presence of the multimodal microprotrusions 3b, 3c,... Can also be seen from the frequency distribution of the distance between the maximum points.

  Needless to say, the multimodal microprotrusions 3b, 3c,... Can improve the scratch resistance due to their presence, but if they do not exist sufficiently, the effect of improving the scratch resistance cannot be fully exhibited. . From such a viewpoint, in the present invention, the ratio of the number of the multimodal microprotrusions 3b, 3c,. In particular, in order to sufficiently exhibit the effect of improving the scratch resistance due to the multimodal microprotrusions 3b, 3c,..., The ratio of the multimodal microprotrusions 3b, 3c,. % Or more. Further, when the ratio of the multimodal microprotrusions 3b, 3c,... Increases to some extent, the effect of the multimodal microprotrusions is saturated and stable production of such microprotrusions becomes difficult. Considering this point, the upper limit of the ratio of the multimodal microprotrusions is preferably 90% or less, more preferably 80% or less.

  Further, when the transparent body 1 having such a microprojection group (3, 3a, 3b, 3c,...) Including the multimodal microprojections 3b, 3c,. It was found that the lengths were different (see FIGS. 12 and 13A). Here, as described above, the height of each microprotrusion is the height of the peak (highest peak) having the highest height at the top of a specific microprotrusion 3 sharing the ridge (base) portion. Say. In the case of a single-peak microprojection 3a such as the microprojection 3 in FIG. 13A, the height of the only peak (maximum point) at the top is the projection height of the microprojection. Further, in the case of a multi-peak microprojection such as the microprojections 3b and 3c in FIG. 13A, the height of the microprojections 3 is the highest peak among the plurality of peaks sharing the ridge at the top. The height. Further, when the heights of all the peaks are the same, the height of the minute protrusion 3 is set to a height common to all the peaks. In this way, when the heights of the microprojections 3 are variously different, for example, even when the shape of the microprojections 3 having a high height is damaged due to contact with an object, the shape of the microprojections 3 having a low height is reduced. Will be maintained. Also by this, in the transparent body 1, local deterioration of the antireflection function can be reduced, and the occurrence of poor appearance can be reduced, and as a result, the scratch resistance can be improved.

  Further, when dust adheres between the microprojections on the surface of the transparent body 1 and the object, when the article slides relative to the transparent body 1, the dust functions as an abrasive to form microprojections ( Group) wear and damage are promoted. In this case, if there is a height difference between the microprotrusions constituting the microprotrusion group, the dust strongly contacts the microprotrusions with a high height, and this sacrifices damage. On the other hand, the contact with the microprojections having a low height is weakened, the damage is reduced, and the antireflection performance is maintained by the microprojections having a low height remaining without being damaged or slightly damaged.

  In addition to this, the microprotrusion group having a distribution (height difference) in the height of each microprotrusion 3 has a broad antireflection performance, and has a multi-wavelength light such as white light or a wideband spectrum. It is advantageous for realizing low reflectivity in the entire spectral band for the light possessed. This is because the wavelength band in which good antireflection performance can be exhibited by such a microprojection group depends not only on the distance d between adjacent projections but also on the projection height.

  In this case, only the high microprojections 3 among the many microprojections 3 come into contact with the surface of various members arranged to face the transparent body 1, for example. Thereby, compared with the case where it uses only the microprotrusions with the same height, the slipping can be remarkably improved, and the handling of the transparent body 1 in the manufacturing process can be facilitated. From the viewpoint of improving the slip as described above, the variation needs to be 10 nm or more when defined by the standard deviation σ. However, when the variation is larger than 50 nm, a feeling of surface roughness due to the variation can be felt. Therefore, the height variation is preferably 10 nm or more and 50 nm or less.

    In addition, when the multimodal microprotrusions 3b, 3c,... Are mixed in this way, the antireflection performance can be improved as compared with the case of using only the single-peak microprotrusions 3a. That is, the multimodal microprotrusions 3b, 3c, etc. as shown in FIG. 8, FIG. 13 and FIG. 14, etc., even when the distance between adjacent protrusions is the same or when the protrusion height is the same, Compared with the unimodal microprotrusions 3a, the light reflectance is further reduced. The reason for this is that the multi-modal microprotrusions 3b, 3c, etc. have a higher rate of change in the effective refractive index in the vicinity of the apex than the single-peak microprotrusions 3a having the same shape below the top (the middle and the heel). This is because it becomes smaller.

That is, in FIG. 13, assuming that z = 0 is set to height H = 0, and it is assumed that the minute protrusions 3a, 3b, etc. are cut at a virtual cutting plane Z = z orthogonal to the height direction (Z-axis direction). The effective refractive index n _ef obtained as an average value of the refractive indexes of the minute protrusions on the surface Z = z and the surrounding medium (usually air) is the refraction of the surrounding medium (here, air) on the cut surface Z = z. The refractive index of the constituent material of n _A = 1, the minute protrusions 3a, 3b,..., N _M > 1, and the total value of the sectional area of the surrounding medium (air) is S _A (z), the minute protrusion 3a. When the total value of the cross-sectional areas of 3b,... Is S _M (z),
n _ef (z) = 1 × S _A (z) / (S _A (z) + S _M (z)) + n _M × S _M (z) / (S _A (z) + S _M (z)) (Formula 1 )
It is represented by This is because the refractive index n _A of the peripheral medium and the refractive index n _M of the constituent material of the microprojections are respectively the total sectional area S _A (z) of the peripheral medium and the total value S _M (z) of the total sectional area of the microprojections. Proportionally distributed value.

Here, when considered on the basis of the monomodal microprotrusions 3a, the multimodal microprotrusions 3b, 3c,... Are split into a plurality of peaks near the top. Therefore, in the virtual cutting plane Z = z that cuts the vicinity of the top, the multimodal microprotrusions 3b, 3c,... Have a relatively lower refractive index than the single-peak microprotrusions 3a,. The ratio of the total cross-sectional area S _A (z) of the medium is further increased as compared with the ratio of the total cross-sectional area S _M (z) of the microprojections having a relatively high refractive index.

As a result, the effective refractive index n _ef (z) at the virtual cut surface Z = z is more peripheral in the multimodal microprotrusions 3b, 3c,. It is close to the refractive index n _{A of the} medium. The difference between the refractive index of the effective refractive index and the surrounding medium multimodal microprotrusions in the plane Z = z | and _multi, the effective refractive index of the unimodal microprojection _{3a | n ef (z) -n} A (z) If the difference from the refractive index of the surrounding medium is | n _ef (z) −n _A (z) | _mono ,
| N _ef (z) −n _A (z) | _multi <| n _ef (z) −n _A (z) | _mono (Formula 2)
It becomes. If n _A (z) = 1,
| N _ef (z) -1 | _multi <| n _ef (z) -1 | _mono (Formula 2A)
It becomes.

  As a result, in the vicinity of the top, a microprojection group including multi-peak microprojections 3b, 3c,... (Including a peripheral medium between the microprojections) is a microprojection group composed of only the single-peak microprojections 3a. In comparison, the difference between the effective refractive index and the refractive index of the surrounding medium (air), more specifically, the rate of change of the refractive index per unit distance in the height direction of the microprojections is further reduced. As a result, it is possible to further increase the continuity of the refractive index in the height direction.

In addition, for the microprojection main body portion, the crease area of the virtual cut surface at the height Z = z of each microprojection is a decreasing function of z (the projection becomes tapered as the distance from the transparent substrate 2 increases). Since the total ridge area SM (z) of the microprotrusions also becomes a decreasing function of z, the change in the effective refractive index n _ef (z) in the height z direction continuously decreases. It is preferable in view of the antireflection effect.

In general, when light is incident on an interface between an adjacent medium having a refractive index n _{0 and} a medium having a refractive index n ₁ , the reflectance R of the light at the interface is set as an incident angle = 0.
R = (n ₁ −n ₀ ) ² / (n ₁ + n ₀ ) ² (Formula 3)
It becomes. From this equation, the smaller the refractive index difference n ₁ −n ₀ of the medium on both sides of the interface, the lower the light reflectivity R at the interface, and when (n ₁ −n ₀ ) approaches 0, R also approaches 0. It will be.

  From (Formula 2), (Formula 2A), and (Formula 3), for the microprojection group including the multimodal microprotrusions 3b, 3c,. The light reflectance is reduced as compared with the projection group consisting only of the projections 3a.

  In the case of the present embodiment having the minute projections shown in FIGS. 8 to 12, the visible light reflectance is incident from the normal direction of the surfaces of the transparent body 1 and the transparent substrate 2 (Z (axis) direction in FIG. 13). It is 0.05 to 0.08% of range with respect to light.

  In addition, when a microprojection group consisting of only single-peak microprojections 3a is used, the distance between adjacent microprojections and the distance between adjacent microprojections are the same, so that the adjacent microprotrusions come into contact with each other and are integrally combined. (So-called sticking) easily occurs. When sticking occurs, the substantial distance d between adjacent protrusions increases by the number of minute protrusions integrated together.

  For example, when four microprojections with d = 200 nm are stuck, the size of the stuck and integrated projection is substantially d = 4 × 200 nm = 800 nm> the longest wavelength in the visible light band (780 nm). The antireflection effect is locally impaired.

On the other hand, in the case of a microprojection group consisting of multimodal microprojections 3b, 3c,..., The distance between adjacent projections d ^PEAK between the peaks near the top is the distance between adjacent projections of the microprojection main body from the heel to the middle. It becomes smaller than d _BASE (d ^PEAK <d _BASE ), and is usually about d ^PEAK = d _BASE / 4 to d _BASE / 2. Therefore, sufficient antireflection performance can be obtained by setting the distance d ^PEAK << λ _MIN between adjacent protrusions between the peaks. However, the ratio of the height of the ridges to the width of the ridge is small in each ridge of the multimodal microprojections 3b, 3c,..., And the height of the apex to the width of the ridge of the single-peak microprojections 3a The ratio (also referred to as aspect ratio) is about 1/2 to 1/10. Therefore, for the same external force, the peaks of the multimodal microprotrusions 3b, 3c,... Are less likely to deform than the single-peak microprotrusions 3a. Moreover, the main body itself of the multimodal microprotrusions 3b, 3c,... Has a greater distance between adjacent protrusions and a higher strength than the ridges. Therefore, in the end, the microprojection group composed of the multimodal microprotrusions 3b, 3c,... Easily achieves both stickiness and low reflectance compared to the projection group composed of the single-peak microprojections 3a. Can be made.

  In addition, even if it is other uses for antireflection of visible light, or under a visible light environment, the antireflection material depends on the assumed antireflection wavelength depending on the environmental conditions where the antireflection material is installed and used. By forming a moth-eye structure and having a height distribution, as described above, even when using materials that are more resistant to abrasion than conventional products and have low hardness due to process requirements, etc., prevent sticking to each other In addition, it is possible to produce an antireflection material having both optically required performance. For example, when it is desired to obtain antireflection performance in the ultraviolet region around 380 nm, the height of the moth eye can be about 50 nm. Similarly, in the infrared region around 700 nm, about 150 nm or more, and 400 nm in consideration of practical use. Is possible. As described above, it is possible to find manufacturing conditions that saturate the height of the arrangement pitch of the moth-eye, and to effectively control the reflectance of the moth-eye. In addition, the top structure of the moth-eye can be improved from the conventional single peak to achieve both height and reflectivity, and it is difficult to cause physical sticking and can effectively reduce reflectivity. Yes.

  By the way, in the roll plate used for the production of such microprojections, by repeating the anodizing treatment and the etching treatment alternately, the micropores are dug while expanding the pore diameter, so that the micropores used for forming the microprojections are formed. Produced. The multimodal microprotrusions 3b, 3c,... Are created by micropores having a concave portion corresponding to the top of the structure, and such micropores were made very close to each other. It is considered that the fine holes are integrally formed by etching. Thereby, in order to mix the multimodal microprotrusions 3b, 3c,... And the monomodal microprotrusions 3a, it can be realized by greatly varying the interval between the micropores produced by anodization, This can be realized by increasing the variation in the anodizing treatment.

  In addition, the variation in the height of the fine holes is caused by the variation in the depth of the fine holes produced in the roll plate, and such a variation in the depth of the fine holes is also caused by the variation in the anodizing process. It can be said.

Accordingly, in this embodiment, the conditions in the anodizing process are set so that the variation is large, the single-peak microprojections and the single-peak microprojections 3a are mixed, and the height of the microprojections 3 varies. A transparent body 1 is produced.

  Here, the applied voltage (formation voltage) in the anodic oxidation treatment and the interval between the micropores are in a proportional relationship, and the variation increases when the applied voltage deviates from a certain range. As a result, using an aqueous solution of sulfuric acid, oxalic acid, and phosphoric acid having a concentration of 0.01M to 0.03M, a voltage of 15V (first step) to 35V (second step: about 2.3 times that of the first step) ) To produce a roll plate for producing transparent body 1 in which multi-peak microprojections 3b, 3c,... And monomodal microprojections 3a are mixed and the heights of the microprojections vary. Can do. If the applied voltage fluctuates, the variation in the spacing between the micropores increases, so that even if the applied voltage is intentionally varied, for example, when an applied voltage is generated using an alternating current power source biased by a direct current power source. Good. The anodizing treatment may be performed using a power source having a large voltage fluctuation rate.

  FIG. 14 is a photograph showing a multi-peak microprojection having a plurality of vertices. FIG. 14A is obtained by AFM, and FIGS. 14B and 14C are obtained by SEM. In FIG. 14 (a), a groove g and a microprojection having three vertices and a groove g and a microprojection having two vertices can be seen, and in FIG. 14 (b), the groove g and four vertices are present. A microprotrusion and a microprotrusion having a groove g and two vertices can be seen, and in FIG. 14C, a microprotrusion having a groove g and three vertices, a microprotrusion having a groove g and two vertices can be seen. be able to. In FIG. 14, an oxalic acid aqueous solution having a water temperature of 20 ° C. and a concentration of 0.02 M is applied, and an anodic oxidation treatment is performed for 120 seconds with an applied voltage of 35V. In the etching process, an anodic oxidation solution was applied to the first step, and an aqueous phosphoric acid solution having a water temperature of 20 ° C. and a concentration of 1.0 M was applied to the second step. The number of times of anodizing treatment and etching treatment is 3 (~ 5) times.

  According to the above configuration, the multi-peak microprotrusions 3b, 3c having a plurality of vertices and the single-peak microprotrusion 3a having one vertices are mixed, so that the scratch resistance is improved as compared with the conventional case. Can be improved.

  Furthermore, the slipperiness can be improved by giving a distribution to the heights of the microprotrusions.

  [Other Embodiments] The specific configuration suitable for the implementation of the present invention has been described in detail above. However, the present invention has various modifications to the configuration of the above-described embodiment without departing from the spirit of the present invention. Further, it can be combined with the conventional configuration.

  That is, in the above-described embodiment, the case where the number of repetitions of the anodizing treatment and the etching treatment is set to 3 (~ 5) times has been described, but the present invention is not limited to this, and the number of repetitions is set to other times. In addition, the present invention can be widely applied to the case where the process is repeated a plurality of times and the final process is anodizing.

  In the above-described embodiment, the case where an acrylate-based ultraviolet curable resin is applied to the shaping resin constituting the microprojection receiving layer has been described. However, the present invention is not limited to this, and the epoxy-based, polyester-based, etc. Various UV curable resins, acrylate-based, epoxy-based, polyester-based and other electron beam-curable resins, urethane-based, epoxy-based and polysiloxane-based thermosetting resins, and various curing forms The present invention can also be widely applied to the case of using a resin for a resin, and further, for example, can be widely applied to a case where a thermoplastic resin such as polyolefin or polycarbonate that has been heated and melted is pressed to form.

  Further, in the above-described embodiment, the microprojection group is formed on the receiving layer 14 of the laminate formed by stacking the receiving layer (ultraviolet curable resin layer) 14 on one surface of the transparent substrate 2 as shown in FIG. The transparent body 1 is formed by shaping and curing the receiving layer 14. The layer structure is a two-layer laminate. However, the present invention is not limited to such a form. Although the transparent body 1 of the present invention is not shown in the figure, a minute projection group (3, 3a, 3b, 3c,...) Is directly applied on one surface of the transparent substrate 2 without interposing another layer. It may be a single layer configuration. Alternatively, one or more intermediate layers (layers that improve substrate surface performance such as adhesion between layers, coating suitability, surface smoothness, etc. on one surface of the transparent substrate 2 are also called a primer layer, an anchor layer, etc. 3), the receiving layer 14 may be formed through the surface of the receiving layer, and a microprojection group may be formed on the surface of the receiving layer.

  Further, among the above-described embodiments, in the embodiment as illustrated in FIG. 2, the microprojection group is formed only on one surface 2 s of the transparent substrate 2 (directly or via another layer). The present invention is not limited to such a form. As shown in FIG. 4, a configuration in which microprojections are formed on both surfaces of the one surface 2 s and the other surface 2 r of the transparent substrate 2 (directly or via other layers) may be employed.

  Further, in the above-described embodiment, as shown in FIG. 13A, the surface connecting the valley bottoms (minimum points of height) between the adjacent minute protrusions is a flat surface having a constant height. However, as shown in FIG. 15, the envelope surface 16 connecting the valley bottoms between the microprotrusions 3 undulates with a period D (that is, D> λmax) equal to or longer than the longest wavelength λmax in the visible light band. It is good also as a structure. Further, the periodic undulation is only in one direction (for example, the X direction) on the XY plane (see FIGS. 13 and 15) parallel to the front and back surfaces of the transparent substrate 2 and in a direction (for example, the Y direction) perpendicular thereto. The height may be constant, or the two directions (X direction and Y direction) on the XY plane may have undulations. An uneven surface (corresponding to the envelope surface 16 at the bottom of each microprojection in the microprojection group) that undulates with a period D satisfying D> λmax is superimposed on the microprojection group composed of a large number of microprojections. Therefore, it is possible to scatter the reflected light remaining without being completely prevented from being reflected, and to make it more difficult to visually recognize the reflected light, particularly the specular reflected light, thereby further improving the antireflection effect.

In addition, when the period D of the envelope surface 16 of the valley surface portion of the uneven surface or the microprojection group has a non-constant distribution over the entire surface, the frequency distribution of the distance between the protrusions is obtained for the uneven surface 16, and the average It is designed as a substitute for the period D with a minimum inter-protrusion distance defined as D _MIN = D _AVG −2Σ, where D _{AVG is} the value and Σ is the standard deviation. That is, the condition that can sufficiently exhibit the scattering effect of the reflected light of the microprojections is D _MIN > λmax. Usually, D or D _MIN is 1 to 200 μm, preferably 10 to 100 μm.

  Further, the height difference between the top and bottom of the uneven surface 16 is about 0.5 to 10 [mu] m, preferably 1 to 5 [mu] m in terms of the 10-point average roughness Rz defined in JIS B0601 (1994). If it is difficult to fit an appropriate envelope surface such that the bottoms of all the microprojections 3 of the microprojection group, that is, all the minimum points are located on the same uneven surface, an appropriate method such as a least square method is used. By the data processing, the envelope surface is formed by the uneven surface having the minimum sum of the distances from the valley bottom (that is, the minimum point) in the entire region in question.

An example of a specific manufacturing method for forming a concavo-convex microprojection group having an uneven surface where the shape of the envelope surface 16 connecting the valley bottoms of each microprojection is D (or D _MIN )> λmax is as follows. It is. That is, in the roll plate manufacturing process, a concavo-convex shape corresponding to the concavo-convex shape of the envelope surface 16 is formed on the surface of a cylindrical (or columnar) shaped base material by sandblasting or mat (matte) plating. Next, an appropriate intermediate layer is formed directly or if necessary on the uneven surface, and then an aluminum layer is laminated. After that, the aluminum layer formed with a surface shape corresponding to the uneven surface is subjected to anodizing treatment and etching treatment in the same manner as in the above-described embodiment to include minute protrusions (3, 3a, 3b, 3c). A projection group is formed.

  Moreover, in the above-mentioned embodiment, although the case where the transparent body 1 by a film shape was produced by the shaping process using a roll plate was described, this invention is not restricted to this, The transparent base material 2 which concerns on the shape of the transparent body 1 Depending on the shape of the mold, for example, when the transparent body 1 is created by processing a flat plate or a single wafer using a mold for molding with a specific curved surface shape, the process related to the molding process, the mold is the transparent body 1 It can change suitably according to the shape of the transparent base material 2 which concerns on the shape of this.

<Application to joinery>
The transparent body 1 in the present invention is a surface (room) of a transparent base material 2 (window glass or the like) that constitutes so-called fittings such as windows, doors, partitions, and wall surfaces of buildings such as houses, stores, offices, schools, and hospitals. It is possible to improve the visibility of the outside world or the daylighting efficiency by arranging it on the inner side, the outdoor side, or both sides thereof. Moreover, it can arrange | position as a transparent sheet | seat of a greenhouse, an agricultural greenhouse, or a transparent board (window material), and can improve the sunlight lighting efficiency.

  In particular, for windows in residential spaces of buildings, by providing the antireflection micro-projection formation region 4 only on the part of the residential space where you want to enjoy outdoor scenery (part of the total area of the window). In the daytime, the outside is bright, and most of the outside surface of the transparent body 1 forming the window is reflected in the same manner as the conventional window glass, so it is difficult to observe the living space from the outside. From there, you can observe landscapes without reflection. Therefore, it is possible to achieve both the appreciation of the scenery from the living space and the privacy protection of the living space.

  FIG. 5 illustrates an example in which the transparent body 1 of the present invention is applied to the glass door 21. In the glass door 21 of FIG. 5, the door body is mainly made of glass (transparent body 1) in which an antireflection microprojection formation region 4 and an antireflection microprojection non-formation region 5 are formed. 22 and the hinge 23 for door attachment are attached, and it is set as the structure without a wrinkle around. The transparent body 1 used for the door is made of glass as the transparent base material 2 and is intermittently non-existent at the height of the eyes of the child (about 80 cm from the ground) and the height of the line of sight of the adult (about 150 cm from the ground). The formation region 5 is provided in a cross-shaped pattern so that the positions thereof are aligned inside and outside, and the other portion is the formation region 4.

  By using such a door, the inside of the store is excellent in daylighting and is bright, and from the outside, the inside of the store can be seen well, so that the customer can easily enter. In addition, since the anti-reflective micro-projection non-formation region 5 is provided at the height of the line of sight, the customer who wants to enter the store recognizes the position of the door by reflection and reflection of the non-formation region 5. Can avoid collision with the glass door.

  FIG. 7 shows an example in which the transparent body 1 of the present invention is applied to an aluminum sash window 51. The aluminum sash window 51 in FIG. 7 is an aluminum sash window 51 configured of the transparent body 1 whose periphery is fixed by a flange 52. On the both sides of the outdoor surface (one surface 2s) and the indoor surface (the other surface 2r) of the aluminum sash window 51, the height of the child's eye of the transparent body 1 of the window glass portion (about about the ground) From the height of 80 cm) to the adult's line of sight (about 150 cm from the ground) is the non-reflective area 5 of the anti-reflective microprojections. The outer side above (about 150 cm from the ground) is an antireflection microprojection formation region 4, and the inner side is a full-surface antireflection microprojection formation region 4.

  Therefore, the outside can be observed well over the entire surface from the relatively dark indoor side during the daytime. On the other hand, from the relatively bright outdoor side, the height of the line of sight is the non-reflective microprojection formation region 5, which prevents the inside from being looked into by reflection or reflection. Furthermore, since both sides of the child's eye height (about 80 cm from the ground) and the adult's line of sight height (about 150 cm from the ground) are the antireflective microprojection formation regions 4, Compared to an aluminum sash window, it can take in external light and brighten the room.

  Furthermore, the transparent body 1 in the present invention can be used for a show window of a store, a product display box, a display window of a museum exhibit, a display box, or the like. The antireflection microprojection formation region 4 and the antireflection microprojection non-formation region 5 are the surface (external side) of the transparent substrate 2 such as a glass plate, or the front and back surfaces (product or display) as shown in FIG. It may be arranged on both sides of the object side. In particular, it is preferable to provide the formation region 4 on the front surface and the formation region 4 formed on the back surface. In this case, the formation region 4 can improve the visibility of products and artworks by preventing light reflection on the surface of the glass plate, and the non-formation region 5 can improve the visibility of the glass plate (transparent body 1). Visibility can be improved and customers and spectators can be prevented from colliding. Further, the design of the formation region 4 and the non-formation region 5 can produce a high-quality design.

  FIG. 6 shows an example in which the present invention is applied to a showcase 41 (product display box). In the showcase 41 of FIG. 6, a glass plate in which a film having antireflection microprotrusions formed on both surfaces is pasted on the four vertical surfaces, and the antireflection microprotrusion forming region 4 is formed on both front and back surfaces. . Further, the non-reflective microprojections 5 having a small circular shape in plan view are arranged on the upper surface so as to be edged for the purpose of avoiding the collision of the observer, and the antireflective microprotrusions are arranged at other portions. The glass (transparent body 1) provided with the formation region 4 is provided.

  The observer can observe as if the exhibits are left on the far side, because the glass on the side and top surface hardly reflects or reflects. Since the non-formation area 5 shines and becomes conspicuous by the reflection of the illumination, the non-formation area 5 of the antireflection minute protrusion on the upper surface is surely recognized and collision is avoided. However, even when observed nearby, there is no reflection or reflection in areas other than the non-formation area 5, and of course, the non-formation area 5 is also as transparent as a normal glass plate, so Can be observed.

  In addition, the bottom, feet, and the stage on which the display is placed are made of glass provided with the formation region 4 of the anti-reflective micro-projections, so that the design is excellent as if the display is displayed in the air, and It is possible to provide an excellent showcase 41 that allows the observer to avoid collision.

  In the figure, since a showcase looking into from above is assumed, the non-reflective microprojection non-formation region 5 is provided only on the upper glass, but a tall showcase or a long showcase viewed from the side, etc. In this case, if necessary, the non-reflective anti-projection region 5 may be provided on the side surface, the height of the line of sight, or the like.

  The transparent body of the present invention and the joinery using the transparent body are excellent in transparency and daylighting, and have excellent anti-collision and privacy protection while having excellent anti-reflection and anti-reflection effects. It can be used for show windows, show cases, joinery and the like. In addition, the transparent body 1 of the present invention can be used for windows and doors of vehicles such as automobiles, railway vehicles, ships, and aircraft.

DESCRIPTION OF SYMBOLS 1 Transparent body 2 Transparent base material 2s One surface 2r The other surface 3 (Antireflection) Microprotrusion 3a Monomodal microprotrusion 3b Multimodal microprotrusion 3c Multimodal microprotrusion 4 (Antireflection microprotrusion) Forming region 5 Non-forming region (of anti-reflective microprojections) 14 UV curable resin layer, receiving layer 16 Enveloping surface 21 Glass door 22 Handle 23 Hinge 41 Showcase 51 Aluminum sash window 52 框 g Groove

Claims (4)

  A transparent body having an antireflective microprojection forming region and an antireflective microprojection non-forming region on at least one surface of the transparent substrate, wherein the antireflective microprojection forming region A transparent body in which protrusions are closely arranged, and an interval between adjacent minute protrusions is equal to or shorter than a shortest wavelength of an electromagnetic wave wavelength band for preventing reflection.   The antireflective microprotrusions formed on one surface of the transparent base material are transparent bodies each having a formation region of the antireflective microprotrusions and a non-formation region of the antireflective microprotrusions on both surfaces of the transparent substrate. 2. The transparent body according to claim 1, wherein the formation region of the antireflective microprojections formed on the other surface coincides with the normal direction of the transparent substrate.   The transparent body according to claim 1, wherein at least a part of the microprojections is a microprojection having a plurality of vertices.   A joinery comprising the transparent body according to any one of claims 1 to 3.