JP2016100326A - Conductive mesh, mesh sheet, and heating plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a conductive mesh used for a heating plate from being viewed and recognized, thereby, to prevent a failure such as reduction in transmittance of the heating plate or density unevenness caused by the conductive mesh being viewed and recognized.SOLUTION: A conductive mesh 50 includes conductive thin wires 51 that defines a number of opening regions 55. An average width of the conductive thin wires 51 is greater than or equal to 5 nm and less than or equal to 500 nm. An average interval between neighboring opening regions 55 is less than or equal to 1000 nm.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a conductive mesh, a mesh sheet having a conductive mesh, and a heating plate.

  2. Description of the Related Art Conventionally, as a defroster device used for a window glass such as a front window and a rear window of a vehicle, a heating plate in which a heating wire made of tungsten wire or the like is arranged on the entire window glass is known (for example, Patent Document 1 and Patent Document 2). See). In this prior art, a heating wire arranged on the entire heating plate is energized, and the heating plate is heated by resistance heating to remove fogging of the window glass forming the heating plate, or snow attached to the window glass. The ice can be melted and the occupant's view can be secured.

JP 2013-173402 A JP-A-8-72674

  While the heating wire provided on such a heat generating plate is formed using an opaque metal material, it is desired that the heating wire is sufficiently invisible from the viewpoint of securing the occupant's field of view. The In particular, when the heating wire is visually recognized, the transmittance of the heat generating plate is lowered, and uneven density can occur. There has been a problem in that adequate reduction of the occupant's field of view is hindered by the reduction in transmittance and the occurrence of shading.

  The present invention has been made in view of the above points, and an object thereof is to provide a conductive mesh effectively prevented from being visually recognized, a mesh sheet having the conductive mesh, and a heat generating plate. And

The conductive mesh according to the present invention is:
Having conductive thin wires defining a number of open areas;
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
The average interval between adjacent opening regions is 1000 nm or less.

The mesh sheet according to the present invention is:
The conductive mesh described above;
And a base material that supports the conductive mesh.

The mesh sheet according to the present invention is:
An uneven structure layer having an uneven surface formed by minute protrusions;
A conductive mesh formed by conductive thin wires extending along the bottom of the concave and convex surfaces of the concave and convex structure layer and between the microprotrusions, and
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
The average interval between adjacent microprotrusions is 1000 nm or less.

The heating plate according to the present invention is:
A pair of glass plates;
A conductive mesh disposed between the pair of glass plates;
A bonding layer disposed between each glass plate and the conductive mesh and bonding the glass plate and the conductive mesh; and
The conductive mesh has conductive thin wires that define a large number of open areas;
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
The average interval between adjacent opening regions is 1000 nm or less.

The heating plate according to the present invention is:
A pair of glass plates;
A mesh sheet disposed between the pair of glass plates;
A bonding layer disposed between each glass plate and the mesh sheet and bonding the glass plate and the mesh sheet; and
The mesh sheet has a base material and a conductive mesh provided on the base material,
The conductive mesh has conductive thin wires that define a large number of open areas;
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
The average interval between adjacent opening regions is 1000 nm or less.

The heating plate according to the present invention is:
A pair of glass plates;
A mesh sheet disposed between the pair of glass plates;
A bonding layer disposed between each glass plate and the mesh sheet and bonding the glass plate and the mesh sheet; and
The mesh sheet is formed by a concavo-convex structure layer having a concavo-convex surface formed by fine protrusions, and a conductive thin wire extending along a valley bottom portion between the microprotrusions of the concavo-convex surface of the concavo-convex structure layer. A conductive mesh,
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
The average interval between adjacent microprotrusions is 1000 nm or less.

  ADVANTAGE OF THE INVENTION According to this invention, it can prevent effectively that the electroconductive mesh used for a heat generating plate is visually recognized. Thereby, the malfunction resulting from visually recognizing a conductive mesh, for example, the fall of the transmittance | permeability of a heat generating plate, and generation | occurrence | production of the shading unevenness can be prevented effectively.

FIG. 1 is a diagram for explaining an embodiment according to the present invention, and is a perspective view schematically showing a vehicle provided with a heat generating plate. In particular, FIG. 1 schematically shows an automobile provided with a front window made of a heat generating plate as an example of a vehicle. FIG. 2 is a view of the heat generating plate as viewed from the normal direction of the plate surface. 3 is a cross-sectional view of the heat generating plate of FIG. FIG. 4 is a plan view illustrating an example of a conductive mesh pattern included in the heat generating plate. FIG. 5 is a cross-sectional view along the normal direction of a mesh sheet having a conductive mesh. FIG. 6 is a perspective view showing an uneven structure layer of the mesh sheet of FIG. FIG. 7 is a plan photograph showing an example of the uneven surface of the uneven structure layer. FIG. 8 is a plan photograph showing an example of the uneven surface of the uneven structure layer. FIG. 9 is a plan photograph showing an example of the uneven surface of the uneven structure layer. FIG. 10 is a graph showing the results of investigating the distribution of the spacing between adjacent microprotrusions on the uneven surface of the uneven structure layer of FIGS. FIG. 11 is a graph showing the results of investigating the height distribution of the fine protrusions on the uneven surface of the uneven structure layer of FIGS. FIG. 12 is a diagram for explaining an example of a method for manufacturing the concavo-convex structure layer. FIG. 13 is a perspective view showing a roll plate used in the manufacturing method of FIG. FIG. 14 is a view for explaining a method of manufacturing the roll plate of FIG. FIG. 15 is a cross-sectional view showing still another example of the uneven surface of the uneven structure layer. FIG. 16 is a diagram for explaining an example of a method of manufacturing a heat generating plate. FIG. 17 is a diagram for explaining an example of a method for manufacturing a heat generating plate. FIG. 18 is a diagram for explaining an example of a method of manufacturing a heat generating plate. FIG. 19 is a diagram for explaining a modification of the method for manufacturing the heat generating plate. FIG. 20 is a diagram for explaining a modification of the method for manufacturing the heat generating plate. FIG. 21 is a diagram for explaining a modification of the method for manufacturing the heat generating plate. FIG. 22 is a diagram for explaining a modification of the method for manufacturing the heat generating plate. FIG. 23 is a diagram for explaining a modification of the method for manufacturing the heat generating plate.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product.

  In the present specification, the terms “plate”, “sheet”, and “film” are not distinguished from each other only based on the difference in names. For example, “mesh sheet” is a concept that includes a member that can be called a plate or a film. Therefore, “mesh sheet” is a member called “mesh plate (substrate)” or “mesh film”. It cannot be distinguished only by the difference.

  In addition, “sheet surface (plate surface, film surface)” means a target sheet-like member (plate-like) when the target sheet-like (plate-like, film-like) member is viewed as a whole and globally. It refers to the surface that coincides with the plane direction of the member or film-like member.

  Furthermore, as used in this specification, the shape and geometric conditions and the degree thereof are specified. For example, terms such as “parallel”, “orthogonal”, “identical”, length and angle values, etc. Without being bound by meaning, it should be interpreted including the extent to which similar functions can be expected.

  1 to 23 are diagrams for explaining an embodiment according to the present invention. Of these, FIG. 1 is a diagram schematically showing an automobile equipped with a heat generating plate, FIG. 2 is a view of the heat generating plate viewed from the normal direction of the plate surface, and FIG. 3 is a heat generating of FIG. It is a cross-sectional view of a board.

  As shown in FIG. 1, an automobile 1 as an example of a vehicle has window glasses such as a front window, a rear window, and a side window. Here, an example in which the front window 5 is configured by the heat generating plate 10 will be described. The automobile 1 has a power source 7 such as a battery.

  FIG. 2 shows the heat generating plate 10 viewed from the normal direction of the plate surface. Moreover, the cross-sectional view corresponding to the III-III line of the heat generating plate 10 of FIG. 2 is shown in FIG. The heat generating plate 10 includes a pair of curved glass plates 11 and 12, a mesh sheet 20 disposed between the pair of curved glass plates 11 and 12, and a joint for joining the glass plates 11 and 12 and the mesh sheet 20. Layers 13 and 14. In the example shown in FIGS. 1 and 2, the heat generating plate 10 is curved, but in FIGS. 3, 18, 22, and 23, the heat generating plate 10 is used for simplification of illustration and easy understanding. The plate 10 and the glass plates 11 and 12 are illustrated in a flat plate shape.

  The mesh sheet 20 connects the base material 30, the conductive mesh 40 formed on the base material 30, the wiring part 15 for energizing the conductive mesh 40, and the conductive mesh 40 and the wiring part 15. And a connecting portion 16.

  In the example shown in FIGS. 2 and 3, the conductive mesh 40 is energized from the power source 7 such as a battery through the wiring portion 15 and the connection portion 16, and the conductive mesh 40 is heated by resistance heating. The heat generated in the conductive mesh 40 is transmitted to the glass plates 11 and 12 through the bonding layers 13 and 14, and the glass plates 11 and 12 are warmed. Thereby, the cloudiness by the dew condensation adhering to the glass plates 11 and 12 can be removed. Moreover, when snow and ice adhere to the glass plates 11 and 12, this snow and ice can be melted. Therefore, a passenger | crew's visual field is ensured favorable.

  For example, in order to produce the heating plate 10, the glass plate 11, the bonding layer 13, the mesh sheet 20, the bonding layer 14, and the glass plate 12 are superposed in this order, and heated / pressurized, whereby the glass plate 11, mesh The sheet 20 and the glass plate 12 are joined by the joining layers 13 and 14.

  In particular, when the glass plates 11 and 12 are used for a front window of an automobile, it is preferable to use a glass plate having a high visible light transmittance so as not to obstruct the view of the passenger. Examples of the material of the glass plates 11 and 12 include soda lime glass and blue plate glass. The glass plates 11 and 12 preferably have a transmittance in the visible light region of 90% or more. Here, the visible light transmittance of the glass plates 11 and 12 is measured within a measurement wavelength range of 380 nm to 780 nm using a spectrophotometer (“UV-3100PC” manufactured by Shimadzu Corporation, JIS K 0115 compliant product). Is specified as an average value of transmittance at each wavelength. The visible light transmittance may be lowered by coloring a part or the whole of the glass plates 11 and 12. In this case, it is possible to block direct sunlight and to make it difficult to visually recognize the inside of the vehicle from outside the vehicle.

  Moreover, it is preferable that the glass plates 11 and 12 have a thickness of 1 mm or more and 5 mm or less. With such a thickness, the glass plates 11 and 12 excellent in strength and optical characteristics can be obtained.

  The glass plates 11 and 12 and the mesh sheet 20 are bonded via bonding layers 13 and 14, respectively. As the bonding layers 13 and 14, layers made of materials having various adhesiveness or tackiness can be used. The bonding layers 13 and 14 preferably have a high visible light transmittance. As a typical joining layer, the layer which consists of polyvinyl butyral (PVB) can be illustrated. The thickness of the bonding layers 13 and 14 is preferably 0.15 mm or more and 0.7 mm or less, respectively.

  The heating plate 10 is not limited to the illustrated example, and may be provided with other functional layers expected to exhibit a specific function. Further, one functional layer may exhibit two or more functions. For example, at least the glass plates 11 and 12 of the heat generating plate 10, the bonding layers 13 and 14, and the base material 30 of the mesh sheet 20 to be described later You may make it provide a function to one. Examples of functions that can be imparted to the heating plate 10 include an antireflection (AR) function, a hard coat (HC) function having scratch resistance, an infrared shielding (reflection) function, an ultraviolet shielding (reflection) function, and a polarization function. An antifouling function and the like can be exemplified.

  Next, the mesh sheet 20 will be described. In the example shown in FIG. 3, the mesh sheet 20 includes a sheet-like base material 30, a concavo-convex structure layer 40 provided on the base material 30, and a conductive material provided on the concavo-convex surface 41 of the concavo-convex structure layer 40. A conductive mesh 50, a wiring portion 15 for energizing the conductive mesh 50, and a connection portion 16 for connecting the conductive mesh 50 and the wiring portion 15. The mesh sheet 20 has substantially the same planar dimensions as the glass plates 11 and 12 and may be arranged over the entire heat generating plate 10 or only in a part of the heat generating plate 10 such as a front portion of a driver's seat. May be.

  In the example shown in FIG. 3, the base material 30 functions as a base material that supports the uneven structure layer 40 and the conductive mesh 50. The base material 30 is an electrically insulating substrate that is transparent in general terms that transmits a wavelength in the visible light wavelength band (380 nm to 780 nm). The base material 30 is not an essential component in the mesh sheet 20 and may be omitted.

  The resin contained in the base material 30 may be any resin as long as it transmits visible light, but a thermoplastic resin can be preferably used. Examples of the thermoplastic resin include acrylic resins such as polymethyl methacrylate, polyester resins such as polyvinyl chloride, polyethylene terephthalate, and amorphous polyethylene terephthalate (A-PET), polyolefin resins such as polyethylene resin and polypropylene, triacetyl cellulose ( Cellulose resins such as cellulose triacetate), polystyrene, polycarbonate resin, AS resin, and the like. In particular, acrylic resin and polyvinyl chloride are preferable because they are excellent in etching resistance, weather resistance, and light resistance.

  Moreover, it is preferable that the base material 30 has a thickness of 0.03 mm or more and 0.15 mm or less in consideration of the retainability of the conductive mesh 50, light transmittance, and the like.

  The conductive mesh 50 will be described with reference to FIGS. 4 and 5. FIG. 4 is a plan view showing an example of an arrangement pattern of the conductive mesh 50. FIG. 5 is a cross-sectional view along the normal direction of the mesh sheet 20 having the conductive mesh 50.

  As shown in FIG. 4, the conductive mesh 50 is a mesh-like material that defines a large number of open regions 55. As shown in FIGS. 4 and 5, the conductive mesh 50 includes a conductive thin wire 51 that defines an opening region 55, such as gold, silver, copper, platinum, aluminum, chromium, molybdenum, nickel, titanium, palladium, It is composed of one or more of indium, tungsten and alloys thereof. The conductive thin wire 51 is formed by a line portion 52 extending in a curved line shape or a straight line shape. In the example shown in FIGS. 3 and 5, the conductive mesh 50 is formed on the concavo-convex surface 41 of the concavo-convex structure layer 40 provided on the base material 30, and is a mesh sheet together with the base material 30 and the concavo-convex structure layer 40. 20 is formed.

  In the example shown in FIGS. 3 and 5, the conductive mesh 50 is formed on the concavo-convex structure layer 40 provided on the substrate 30. The uneven structure layer 40 has an uneven surface 41 formed by minute protrusions 42. Then, the conductive thin wires 51 forming the conductive mesh 50 extend along the valley bottom portion 44 between the minute protrusions 42 in the uneven surface 41 of the uneven structure layer 40. Therefore, the mesh sheet 20 shown in FIGS. 3 and 5 includes the uneven surface 21 corresponding to the unevenness of the uneven surface 41 of the uneven structure layer 40. The irregularities on the irregular surface 21 of the mesh sheet 20 are formed by the minute projections 22 formed corresponding to the minute projections 42 forming the irregular surface 41 of the irregular structure layer 40. The mesh sheet 20 can exhibit a function caused by the unevenness of the uneven surface 21, for example, an antireflection function described later, a diffusion function, and the like.

  In the conductive mesh 50 having visible light permeability, it is preferable that the conductive fine wire 51 is difficult to be visually recognized. In addition, the sheet resistance of the conductive mesh 50 is preferably in an appropriate range so that the heat generation function expected of the conductive mesh 50 can be sufficiently exhibited. In the conductive mesh 50 according to the present invention, the average line width of the conductive thin wires 51 is 5 nm or more and 500 nm or less, and the average interval between adjacent opening regions 55 is 50 nm or more and 1000 nm or less. Here, the interval between the opening regions 55 is an arrangement interval between two opening regions 55 adjacent to each other via one line portion 52, and can be, for example, a linear distance between the centers of gravity of the opening regions 55. Further, the thickness of the conductive fine wire 51 of the conductive mesh 50 is preferably 10 nm or more, and more preferably 100 nm or more, from the viewpoint of ensuring conductivity.

  Each dimension of the conductive mesh 50 such as the line width of the conductive thin wire 51 and the interval between two adjacent opening regions 55 needs to be specified by examining the entire region of the conductive mesh 50 and calculating the average value. Actually, one section having an area expected to reflect the overall tendency of the object to be investigated (the line width of the conductive thin wire 51, the interval between two adjacent open regions 55, etc.) The number can be determined by examining the number considered to be appropriate in consideration of the degree of variation of the object to be investigated. The values specified in this way can be treated as the average value of the line width of the conductive thin wires 51 and the average value of the interval between two adjacent opening regions 55, respectively. For example, in the conductive mesh 50 manufactured by the manufacturing method described below with the value described immediately before as a target, an average is calculated by measuring 30 points included in a 30 mm × 30 mm region with an electron microscope. Thus, the line width of the connection element 20, the size of the opening region 55, and the like can be specified.

  A general conductive mesh is a method of forming a metal film on a substrate by, for example, vapor deposition, sputtering, foil transfer, coating, etc., and etching the metal film using a desired photoresist pattern as a mask. , A method of exposing and developing a conductive photosensitive agent (for example, an emulsion in which silver halide grains are diffused) in a desired pattern, or a conductive ink (for example, conductive ink in which conductive metal particles are dispersed) It can form on a base material by methods, such as the method of printing with a desired pattern on a base material. However, the conductive mesh 50 in which the average value of the line width of the conductive thin wire 51 and the average value of the interval between two adjacent opening regions 55 are set in the above-described fine range is not obtained by these conventionally known methods. It is difficult to produce.

As shown in FIG. 5, the conductive thin wire 51 provided on the valley bottom 44 of the concavo-convex structure layer 40 first forms the concavo-convex structure layer 40 on the substrate 30. As an example, the concavo-convex structure layer 40 can be produced by shaping an ionizing radiation curable resin as described in detail later.
As another example, the concavo-convex structure layer 40 can also be produced by spreading beads on the resin composition so that the top of the resin composition is exposed from the resin composition, and then curing the resin composition.

  Thereafter, as shown by a dotted line in FIG. 5, a metal thin film 58 is formed on the uneven surface 41 of the uneven structure layer 40. A method for forming the metal thin film 58 is not particularly limited, and examples thereof include gas phase methods (dry processes) such as sputtering, ion plating, vacuum deposition, and CVD. Thereafter, a part of the metal thin film 58 is removed by etching, polishing, or the like that erodes only the metal thin film 58 without eroding the concavo-convex structure layer 40. At this time, by etching or polishing, the metal thin film 58 can be removed from a portion located on the top 43 of the uneven surface 41 of the uneven structure layer 40. Then, by adjusting the removal amount of the metal thin film 58, it is possible to obtain the conductive thin wire 51 made of metal remaining only in the valley bottom portion 44 of the concavo-convex structure layer 40.

  Instead of forming the metal thin film 58 by film formation and removing part of the metal thin film 58, an appropriate amount of a composition containing metal particles is applied onto the uneven surface 41 of the uneven structure layer 40 and further cured to thereby form the uneven surface 41. The conductive thin wire 51 can also be formed on the bottom of the valley 44. Alternatively, by applying a composition containing metal particles onto the concavo-convex surface 41 of the concavo-convex structure layer 40, further curing, and further removing the cured metal-containing composition by etching or polishing as described above, The conductive thin wire 51 can also be formed on the valley bottom 44 of the surface 41. Further, the coating amount of the composition containing metal particles on the uneven surface 41 may be adjusted by scraping and removing the composition applied to the uneven surface 41 of the uneven structure layer 40.

  As described above, according to the conductive mesh 50 in which the average line width of the conductive thin wires 51 is 5 nm or more and 500 nm or less and the average interval between adjacent opening regions 55 is 1000 nm or less, generally, the human eyes It becomes difficult to resolve the conductive mesh 50. That is, the conductive mesh 50 described here can be effectively avoided from being visually recognized. Thereby, the permeability | transmittance of the electroconductive mesh 50 and the mesh sheet | seat 20 can be improved effectively. In addition, the occurrence of shading unevenness due to the visual recognition of the conductive mesh 50 can be effectively prevented. The shading unevenness is considered to be a phenomenon in which the transmittance is locally reduced due to the nonuniformity of the density distribution of the conductive thin wires 51 and the nonuniformity of the line width of the conductive thin wires 51 in the pattern of the conductive mesh. ing. According to the conductive mesh 50 described above, since the average line width of the conductive thin wires 51 is thinned to 500 nm or less, the line portion 52 of the conductive thin wires 51 is sufficiently invisible, and the shading unevenness is visually recognized. It becomes difficult to be done.

Next, the uneven structure layer 40 will be described. As described above, in the example shown in FIGS. 3 and 5, the conductive mesh 50 is formed by the conductive thin wires 51 extending through the valley bottom portions 44 between the minute protrusions 42 in the uneven surface 41 of the uneven structure layer 40. Is formed. Therefore, the mesh sheet 20 shown in FIG. 5 includes the uneven surface 21 corresponding to the unevenness of the uneven surface 41 of the uneven structure layer 40. The irregularities on the irregular surface 21 of the mesh sheet 20 are formed by the minute projections 22 formed corresponding to the minute projections 42 forming the irregular surface 41 of the irregular structure layer 40. The minute protrusions 42 of the concavo-convex structure layer 40 are arranged at an average interval d _AVG of 1000 nm or less. That is, the uneven structure layer 40 is formed as a so-called moth-eye structure, and as a result, the uneven surface 21 of the mesh sheet 20 can exhibit an excellent antireflection function. Hereinafter, such an uneven structure layer 40 will be described in detail.

The concavo-convex structure layer 40 has a concavo-convex surface 41 formed by minute protrusions 42 arranged at an average interval d _AVG of 1000 nm or less. Here, the “minute” of the minute protrusions 42 means that the minute protrusions 42 are minute enough to be arranged with an average interval d _AVG of 1000 nm or less. As described above, the conductive thin wire 51 of the conductive mesh 50 extends through the valley bottom 44 of the concavo-convex surface 41 of the concavo-convex structure layer 40. Accordingly, each of the opening regions 55 defined in the conductive thin wire 51 of the conductive mesh 50 is provided corresponding to one minute protrusion 42. Therefore, the average of the interval between the two adjacent opening regions 55 described above can be the same as the average of the arrangement interval of the protrusions of the minute protrusions 42. For this reason, in the example shown by FIGS. 3-5, the average space | interval by which the microprotrusion 22 which makes the uneven surface 21 formed in the final mesh sheet | seat 20 is also arrange | positioned also becomes a space | interval of 1000 nm or less.

  The thickness T of the concavo-convex structure layer 40 is not particularly limited, but can be 10 to 300 μm as an example. In this case, the thickness T of the concavo-convex structure layer 40 forms the concavo-convex surface 41 of the concavo-convex structure layer 40 from the interface on the substrate 30 side of the concavo-convex structure layer 40 as shown in FIGS. The height along the normal direction nd to the film surface of the conductive mesh 50 up to the top 43 of the fine protrusion 42 is meant.

  The concavo-convex structure layer 40 can be a layer containing a resin, and can be a layer made of a cured product of a resin composition. The resin composition used for forming the concavo-convex structure layer 40 includes at least a resin and, if necessary, other components such as a polymerization initiator.

The uneven surface 41 of the uneven structure layer 40 will be described. In FIG. 6, the uneven surface 41 of the uneven structure layer 40 is shown. The concavo-convex surface 41 is formed by minute protrusions 42 arranged at an average interval d _AVG of 1000 nm or less. Preferably, the maximum distance d _MAX between the minute protrusions 42 forming the uneven surface 41 of the uneven structure layer 40 is 1000 nm or less. For this reason, it can be effectively avoided that the conductive thin wire 51 extending through the valley bottom portion 44 between the minute protrusions 42 in the uneven surface 41 of the uneven structure layer 40 is visually recognized.

From the viewpoint of expecting an antireflection function due to the uneven surface 41, the minute protrusions 42 formed on the uneven structure layer 40 have a visible light whose average distance d _AVG between adjacent minute protrusions 42 prevents reflection. More preferably, they are arranged close to each other so as to be equal to or shorter than the shortest wavelength Λ _min of the wavelength band (d _AVG ≦ Λ _min ). More preferably, they are closely arranged so that the maximum interval d _MAX between adjacent microprojections 42 is equal to or less than Λ _min (d _MAX ≦ Λ _min ). As described above, the shortest wavelength Λ _min of the visible light wavelength band is set to 380 nm in the environment where the conductive mesh 50 is used and there is light in various wavelength bands without particular limitation. In addition, the arrangement interval d of the minute protrusions 42 can be set to 100 to 300 nm in consideration of variations in the arrangement interval d. Further, the adjacent minute protrusions 42 corresponding to the distance d are so-called adjacent minute protrusions 42, which are in contact with the valley bottom portion 44 of the minute protrusion which is the base portion on the base material 30 side. In the mesh sheet 20, as described above, the arrangement interval d of the microprojections 42 is the arrangement interval of the microprojections 22 of the mesh sheet 20 and also corresponds to the interval of the opening regions 55 of the conductive mesh 50. The adjacent minute protrusions 42 can also be said to be two minute protrusions 42 that are partitioned by one line portion 52 of the conductive mesh 50.

The minute protrusions 42 are defined in more detail as follows. The anti-reflection function by the so-called moth-eye structure is intended to prevent reflection by continuously changing the effective refractive index at the interface between the moth-eye structure and the adjacent medium in the thickness direction. It is necessary to satisfy certain conditions for the protrusions. With respect to the spacing of the projections of the moth-eye structure, which is one of these conditions, for example, as disclosed in Japanese Patent Application Laid-Open No. 50-70040, Japanese Patent No. 4632589, etc., the minute projections are regularly arranged at a constant period. If there is, the interval d between adjacent minute protrusions is the protrusion arrangement period P (d = P). As a result, when the longest wavelength in the visible light band is λ _MAX and the shortest wavelength is λ _min , the minimum necessary condition that can provide an antireflection effect at the longest wavelength in the visible light band is Λ _min = λ _MAX . Therefore, P ≦ λ _MAX , and the necessary and sufficient condition that can exhibit the antireflection effect for all wavelengths in the visible light band is Λ _min = λ _min , and therefore P ≦ λ _min .

Note that the wavelengths λ _MAX and λ _min may _vary somewhat depending on observation conditions, light intensity (luminance), individual differences, and the like, but are typically λ _MAX = 780 nm and λ _min = 380 nm. The A preferable condition that can more reliably exhibit an antireflection effect for all wavelengths in the visible light band is d ≦ 300 nm, and a more preferable condition is d ≦ 200 nm. Note that the lower limit of the period d is usually d ≧ 50 nm, preferably d ≧ 100 nm, for reasons such as the appearance of an antireflection effect and the securing of isotropy (low angle dependency) of the reflectance. On the other hand, the height H of the protrusion is set to H ≧ 0.2 × λ _MAX = 156 nm (assuming λ _MAX = 780 nm) from the viewpoint of exhibiting a sufficient antireflection effect.

  On the other hand, when the minute protrusions 42 are irregularly arranged, the distance d between the adjacent minute protrusions 42 varies. More specifically, as shown in FIG. 7, when the microprojections 42 are not regularly arranged at a constant period in a plan view as viewed from the normal direction to the front surface or the back surface of the base material 30, the following is performed. Calculated.

  (1) That is, first, an in-plane arrangement of projections (planar shape of projection arrangement) is detected using an atomic force microscope (AFM) or a scanning electron microscope (SEM). FIG. 7 is an enlarged photograph actually obtained by an atomic force microscope.

  (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. In addition, as a method for obtaining a maximum point, a method for obtaining a local maximum point by sequentially comparing a planar view shape with an enlarged photograph of a corresponding cross-sectional shape, a method for obtaining a local maximum point by image processing of a planar view enlarged photograph, and a method obtained from an AFM. Various methods such as analysis of height data of the microprojections can be applied. FIG. 8 is a diagram showing the detection result of the local maximum point by processing the in-plane distribution data of the height corresponding to the enlarged photograph shown in FIG. 7 (the AFM image grayscale data in FIG. 7 is also roughly corresponding). 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. It is a net-like figure consisting of a collection of triangles. Each triangle is called a Delaunay triangle, and a side of each triangle (a line segment connecting adjacent generating points) is called a Delaunay line. FIG. 9 is a diagram in which the Delaunay diagram (represented by white line segments) obtained from FIG. 8 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 line segment length of each Delaunay line, that is, the frequency distribution of the distance between adjacent maximum points (hereinafter referred to as the distance between adjacent protrusions) is obtained. FIG. 10 is a histogram of the frequency distribution created from the Delaunay diagram of FIG. If there is a groove-like recess or the like at the top 43 of the microprojection 42, or if the top 43 is split into a plurality of peaks, there is a recess at the top of such projection from the obtained frequency distribution. The data resulting from the fine structure and the fine structure in which the top 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.

  Specifically, in the fine structure in which the concave portion exists in the top portion 43 of the microprojection 42 and the fine structure related to the multimodal microprojection 42 in which the top portion 43 is divided into a plurality of peaks, such a fine structure is used. From the numerical range in the case of the single-peaked microprotrusion 42 that is not provided, the distance between adjacent maximum points is clearly greatly 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-peaked microprojections are selected from an enlarged photograph of the microprojections (group) as shown in FIG. The value of is sampled and the value clearly deviates from the numerical range obtained by sampling (usually data whose value is ½ or less of the average distance between adjacent maximum points obtained by sampling) To detect the frequency distribution. In the example of FIG. 10, data with a distance between adjacent maximal points of 56 nm or less (the leftmost small mountain indicated by arrow A) is excluded. FIG. 10 shows a frequency distribution before performing such exclusion processing. Incidentally, such exclusion processing may be executed by setting the above-described maximum point detection filter.

(5) The average value (average interval) d _AVG and the standard deviation σ are obtained from the frequency distribution of the distance d between adjacent protrusions thus obtained. Here, when the frequency distribution obtained in this manner 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. Thereby, the maximum value d _{MAX of the} distance between adjacent protrusions is set to d _MAX = d _AVG + 2σ, and in this example, d _MAX = 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. 11 is a diagram showing a histogram of the frequency distribution of the protrusion height H with the protrusion root position obtained in this way as a reference (height 0). The average value _HAVG of the protrusion height and the standard deviation σ are obtained from the frequency distribution based on the histogram. Here, in the example of FIG. 11, the average value H _AVG = 178 nm and the standard deviation σ = 30 nm. Thus in this example, the height of the projections is an average value _H AVG = 178 nm. In the histogram of the projection height H shown in FIG. 11, in the case of a multi-peak microprojection, the plurality of data are mixed for one projection by having a plurality of apexes. Therefore, in this case, the frequency distribution is obtained by adopting, as the projection height of the microprojection, the top portion having the highest height from among the plurality of apexes belonging to the same microprojection.

  Note that the reference position for measuring the height of the protrusion described above is based on the valley bottom 44 between the adjacent minute protrusions as a reference for the height of zero. However, when the height of the valley bottom 44 varies depending on the location (for example, as shown in FIG. 15, when the height of the valley bottom 44 has undulation at a period larger than the distance between adjacent protrusions of the minute protrusions, etc. (1) First, the average value of the height of each valley bottom 44 measured from the front surface or the back surface of the substrate 30 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 surface or the back surface of the substrate 30 is considered as a reference surface. (3) Then, the height of each microprotrusion from the reference surface is calculated by setting the reference surface to a height of 0 again.

When the height of the valley bottom 44 between the adjacent minute protrusions 42 varies depending on the location, for example, as shown in FIG. 15, the envelope surface connecting the valley bottoms between the minute protrusions has the longest wavelength λ _{MAX in the} visible light band. In some cases, the above period D (that is, D> λ _MAX ) undulates. The periodic undulation is only in one direction (for example, the X direction) on a plane (XY plane in FIG. 15) parallel to the front and back surfaces of the base material 30 and at a constant height in a direction (for example, the Y direction) perpendicular thereto. Alternatively, the two directions (X direction and Y direction) in a plane (XY plane in FIG. 15) parallel to the front and back surfaces of the base material 30 may have undulations. The concave and convex surface 46 that undulates with a period D satisfying D> λ _MAX is superimposed on a microprojection group consisting of a large number of microprojections, thereby scattering the reflected light remaining without being completely prevented from being reflected by the microprojection group, It is further difficult to visually recognize the shiodome reflected light, in particular, the specular reflected light, so that the transmission visibility of the conductive mesh 50 can be further improved.

When the period D of the concavo-convex surface 46 is not constant over the entire surface and has a distribution, the frequency distribution of the distance between the convex portions is obtained for the concavo-convex surface, and the average value is D _AVG and the standard deviation is Σ. When
D _min = D _AVG -2Σ
Is designed as an alternative to the period D with the minimum distance between adjacent protrusions defined as That is, the conditions that can sufficiently exhibit the scattering effect of the reflected light of the microprojections are as follows:
D _min > λ _MAX
It is. Usually, D or D _min can be 200 μm or less.

In the case where the protrusions are irregularly arranged, the average value d _{AVG of the} distances between adjacent protrusions and the average value (average height) _HAVG of the heights of the protrusions thus obtained are regularly arranged. It has been found that satisfying the above-mentioned conditions in some cases is effective to some extent from the viewpoint of imparting an effective antireflection function to the uneven structure layer 40. Specifically, the condition of the distance between the microprotrusions that exhibits the antireflection effect is d _AVG ≦ Λ _min . Since the minimum necessary condition that can exhibit the antireflection effect at the longest wavelength in the visible light band is Λ _min = λ _MAX , d _AVG ≦ λ _MAX is satisfied, and antireflection is performed for all wavelengths in the visible light band. The necessary and sufficient condition that can produce the effect is Λ _min = λ _min , and therefore d _AVG ≦ λ _min . A preferable condition that can effectively exhibit the antireflection effect for all wavelengths in the visible light band is d _AVG ≦ 300 nm, and a more preferable condition is d _AVG ≦ 200 nm. Further, for reasons such as ensuring the manifestation of the antireflection effect, d _AVG ≧ 50 nm is usually satisfied, and d _AVG ≧ 100 nm is preferable. Such a condition is a condition relating to the interval between the opening regions 55 for making the conductive mesh 50 invisible, that is, the average of the interval between the two adjacent opening regions 55 or the minute protrusions 42 is 50 nm or more and 1000 nm or less. Satisfy the conditions.

Further, the height of the protrusion is set to H _AVG ≧ 0.2 × λ _MAX = 156 nm (assuming λ _MAX = 780 nm) in order to exhibit a sufficient antireflection effect. From the viewpoint of enabling an excellent antireflection function to be exhibited even in the mesh sheet 20 on which the conductive mesh 50 is formed, the conductive mesh is set so that the protrusion height of the fine protrusions 22 of the mesh sheet 20 is 156 nm or more. In consideration of the thickness of the 50 conductive thin wires 51, it is preferable to determine the projection height of the microprojections 42 of the concavo-convex structure layer 40.

7 to 11, d _MAX = 234 nm ≦ λ _MAX = 780 nm, which satisfies the condition of d _MAX ≦ λ _MAX , and the uneven structure layer 40 and the mesh sheet 20 have a sufficient antireflection effect. I know you get. In addition, since the shortest wavelength λ _{min in the} visible light band is 380 nm, the concavo-convex structure layer 40 and the mesh sheet 20 may also satisfy the sufficient condition d _MAX ≦ λ _{min for} exhibiting the antireflection effect in the entire visible light wavelength band. Recognize. When the average protrusion the height _H AVG = 178 nm Also, the average projection height _{H AVG ≧ 0.2 × λ MAX =} 156nm becomes (as the longest wavelength lambda _MAX = 780 nm in the visible light wavelength band), the conductive mesh 50 It can be seen that the conditions regarding the height of the protrusions for realizing a sufficient antireflection effect are also satisfied. Note since the standard deviation sigma = 30 _nm, since the relationship between the _{H AVG -σ = 148nm <0.2 ×} λ MAX = 156nm is satisfied, statistically, more than 50% of the total microprojection 42, 84 % Or less satisfies the condition related to the height of the protrusion (178 nm or more).

  Next, a method for manufacturing the uneven structure layer 40 will be described. FIG. 12 is a diagram illustrating an example of a method for manufacturing the concavo-convex structure layer 40. In the illustrated manufacturing method, in the resin supplying step, an uncured and liquid ultraviolet curable resin that forms the concavo-convex structure layer 40 is applied to the base material 30 in the form of a strip film by the die 92. In addition, about application | coating of ultraviolet curable resin, not only the case by the die | dye 92 but various methods are applicable. Subsequently, the substrate 30 is pressed against the peripheral side surface of a roll plate (mold) 93 which is a mold for forming the concavo-convex structure layer by the pressing roller 94, and thereby the liquid acrylate is uncured on the substrate 30. The ultraviolet curable resin is brought into close contact, and the ultraviolet curable resin is sufficiently filled in the concave portions having fine irregularities formed on the peripheral side surface of the roll plate 93. In this state, the ultraviolet curable resin is cured by irradiation with ultraviolet rays, and thereby the concavo-convex structure layer 40 having the fine protrusions 42 on the surface of the substrate 30 is produced. Next, the base material 30 is peeled from the roll plate 93 using the peeling roller 95 integrally with the concavo-convex structure layer 40 made of a cured ultraviolet curable resin. Thereafter, as described above, the conductive mesh 50 is formed using the unevenness of the uneven surface 41 of the uneven structure layer 40. Thereby, the electroconductive mesh 50 is obtained.

  FIG. 13 is a perspective view showing the configuration of the roll plate 93. The roll plate 93 has a fine concavo-convex shape for shaping the concavo-convex surface 41 of the concavo-convex structure layer 40 on the peripheral side surface of the base material, which is a cylindrical metal material, by repeating anodizing treatment and etching treatment. The For this reason, a columnar or cylindrical member in which a high-purity aluminum layer is provided on at least a peripheral side surface is used as the base material. As an example, 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. Instead of the stainless steel pipe, a pipe material such as copper or aluminum may be applied. In the roll plate 93, fine holes are formed densely on the peripheral side surface of the base material by repeating the anodizing treatment and the etching treatment, and the fine holes are dug, and the diameter of the roll plate 93 increases as it approaches the opening. The concavo-convex shape is produced by gradually increasing the diameter of the fine holes. As a result, the roll plate 93 is densely formed with fine holes whose diameter gradually decreases in the depth direction, and the concavo-convex structure layer 40 has a diameter gradually corresponding to the fine holes as it approaches the top 43. As a result, a concavo-convex surface 41 made up of a large number of small protrusions 42 is produced. At that time, the roll plate 93 capable of shaping the uneven surface 41 described above by appropriately adjusting various conditions such as the purity (impurity amount), crystal grain size, anodizing treatment and / or etching treatment of the aluminum layer. Can be produced.

  FIG. 14 is a diagram showing a method for manufacturing the roll plate 93. In this manufacturing method, first, the peripheral side surface of the base material is made into a super-mirror surface by an electrolytic composite polishing method that combines an electrolytic elution action and a rubbing action by abrasive grains (electropolishing). Subsequently, aluminum is sputtered on the peripheral side surface of the base material to produce a high-purity aluminum layer. Next, the base material is processed by alternately repeating the anodic oxidation steps A1,..., AN, and the etching steps E1,.

  In this manufacturing method, in the anodic oxidation steps A1,..., AN, a fine hole is formed on the peripheral side surface of the base material by the anodic oxidation method, and the produced fine hole is further dug. Here, in the anodic oxidation step, various methods applied to the anodic oxidation of aluminum 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 can be formed in a shape corresponding to the shape of the fine protrusions 42 to be produced by managing the liquid temperature, the applied voltage, the time for anodization, and the like. it can.

In the subsequent etching process E1,..., EN, the mold is immersed in an etching solution, the hole diameter of the fine hole produced and dug in the anodizing process A1,. These fine holes are shaped so that the hole diameter becomes smaller and smoother.
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. As a result, in this manufacturing process, the anodizing process and the etching process are alternately performed a plurality of times, so that fine holes for forming are formed on the peripheral side surface of the base material.

  The roll plate 93 for producing the concavo-convex structure layer 40 described with reference to FIG. 15, that is, the concavo-convex structure layer 40 in which the height of the valley between the adjacent minute protrusions 42 varies depending on the location, Can be manufactured in this way. That is, in the manufacturing process of the roll plate 93, a concavo-convex shape corresponding to the concavo-convex shape of the concavo-convex surface 46 is formed on the surface of a cylindrical (or columnar) 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. Thereafter, an aluminum layer having a surface shape corresponding to the uneven surface is subjected to anodizing treatment and etching treatment in the same manner as described above to form an uneven surface 41 including minute protrusions 42. 93 is obtained.

  By using the roll plate 93 produced in this way, the concavo-convex structure layer 40 can be produced. As described above, by using the fine uneven surface 41 of the uneven structure layer 40, the conductive mesh 50 in which the line width of the conductive thin wire 51 is narrow and the interval between the opening regions 55 is narrow can be easily manufactured. It becomes possible. The conductive mesh 50 thus manufactured can be effectively avoided from being visually recognized due to the narrow width of the conductive thin wire 51 and the narrowness of the interval between the opening regions 55.

  Next, an example of a method for manufacturing the heat generating plate 10 will be described with reference to FIGS. 3 and 16 to 18. 16-18 is sectional drawing which shows an example of the manufacturing method of the heat generating plate 10 in order.

First, the base material 30 is prepared. The base material 30 is an electrically insulating base material that is transparent and is generally referred to as transmitting a wavelength in a visible light wavelength band (380 nm to 780 nm). Next, the concavo-convex structure layer 40 having the concavo-convex surface 41 formed by the fine protrusions 42 is formed on the substrate 30. FIG. 16 shows a structure in which the concavo-convex structure layer 40 is formed on the substrate 30. The concavo-convex surface 41 of the concavo-convex structure layer 40 is formed by minute protrusions 42 arranged at an average interval d _AVG of 1000 nm or less. As an example, the concavo-convex structure layer 40 is manufactured by shaping an ionizing radiation curable resin using the above-described roll plate 93 in which fine holes are densely formed as described with reference to FIG. obtain. In addition, the uneven | corrugated structure layer 40 can also be produced not only using the above-mentioned method demonstrated with reference to FIG. 12 but using another nanoimprint technique, and the top part is exposed from a resin composition on a resin composition. The concavo-convex structure layer 40 can also be produced by spreading beads as described above and then curing the resin composition.

  Next, as shown in FIG. 17, the conductive thin wire 51 forming the conductive mesh 50 is formed on the valley bottom 44 of the concavo-convex structure layer 40 to produce the mesh sheet 20. As an example, as described with reference to FIG. 5, the metal thin film 58 is formed on the uneven surface 41 of the uneven structure layer 40, and thereafter, the etching that erodes only the metal thin film 58 without eroding the uneven structure layer 40. A part of the metal thin film 58 is removed by polishing, polishing, or the like, and the conductive thin wire 51 made of metal remaining only in the valley bottom 44 of the concavo-convex structure layer 40 can be produced. In addition to the above-described method described with reference to FIG. 5, an appropriate amount of a composition containing metal particles is applied onto the concavo-convex surface 41 of the concavo-convex structure layer 40 and further cured, whereby the valley bottom of the concavo-convex surface 41 is obtained. The conductive thin wire 51 can also be formed on the portion 44. Alternatively, by applying a composition containing metal particles onto the concavo-convex surface 41 of the concavo-convex structure layer 40, further curing, and further removing the cured metal-containing composition by etching or polishing as described above, The conductive thin wire 51 can also be formed on the valley bottom 44 of the surface 41.

As described above, the concavo-convex surface 41 of the concavo-convex structure layer 40 is formed by the minute protrusions 42 arranged at an average interval d _AVG of 1000 nm or less. Therefore, the conductive thin wires 51 forming the conductive mesh 50 formed on the valley bottom portion 44 of the concavo-convex structure layer 40 define a large number of opening regions 55 respectively corresponding to the large number of minute protrusions 42. For this reason, the average interval between two adjacent opening regions 55 is the same as the average d _AVG of the arrangement interval of the microprojections 42. That is, the average interval between two adjacent opening regions 55 is 1000 nm or less. Therefore, the average interval at which the minute protrusions 22 forming the uneven surface 21 formed on the final mesh sheet 20 are arranged is also an interval of 1000 nm or less.

  Thereafter, the glass plate 11, the bonding layer 13, the mesh sheet 20, the bonding layer 14, and the glass plate 12 are superposed in this order, and heated and pressurized. In the example shown in FIG. 18, the bonding layer 13 is temporarily bonded to the glass plate 11 and the bonding layer 14 is temporarily bonded to the glass plate 12. Next, the glass plate 11, the mesh sheet 20, and the bonding layer to which the bonding layer 13 is temporarily bonded so that the side on which the bonding layers 13 and 14 of the glass plates 11 and 12 are temporarily bonded faces the mesh sheet 20, respectively. The glass plate 12 to which 14 is temporarily bonded is superposed in this order, and heated and pressurized. Thereby, the glass plate 11, the mesh sheet | seat 20, and the glass plate 12 are joined via the joining layers 13 and 14, and the heat generating plate 10 shown in FIG. 3 is manufactured.

  The heat generating plate 10 shown in FIG. 3 includes a pair of glass plates 11 and 12, a conductive mesh 50 disposed between the pair of glass plates 11 and 12, and the glass plates 11 and 12 and the conductive mesh 50. And the bonding layers 13 and 14 for bonding the glass plates 11 and 12 and the conductive mesh 50 to each other, and the conductive mesh 50 includes a conductive thin wire 51 that defines a large number of opening regions 55. The average line width of the conductive thin wires 51 is 5 nm or more and 500 nm or less, and the average interval between adjacent opening regions 55 is 1000 nm or less. According to such a conductive mesh 50 and the heat generating plate 10, it is difficult to resolve the conductive mesh 50 with human eyes. That is, the conductive mesh 50 can be effectively avoided from being visually recognized. Thereby, the permeability | transmittance of the electroconductive mesh 50 can be improved effectively. In addition, the occurrence of shading unevenness due to the visual recognition of the conductive mesh 50 can be effectively prevented.

  3 includes a pair of glass plates 11 and 12, a mesh sheet 20 disposed between the pair of glass plates 11 and 12, and the glass plates 11 and 12 and the mesh sheet 20 respectively. And the bonding layers 13 and 14 for bonding the glass plates 11 and 12 and the mesh sheet 20 to each other. The mesh sheet 20 has a base material 30 and a conductive material provided on the base material 30. The conductive mesh 50 has conductive fine wires 51 that define a large number of opening regions 55, and the average line width of the conductive fine wires 51 is 5 nm or more and 500 nm or less, and adjacent to each other. The average interval between the opening regions 55 is 1000 nm or less. According to such a mesh sheet 20 and the heat generating plate 10, since the mesh sheet 20 having the base material 30 and the conductive mesh 50 provided on the base material 30 is included, Handling becomes easy. In particular, the mesh sheet 20 can be produced by a so-called roll-to-roll method in which the base material 30 is supplied from a roll-shaped roll and the produced mesh sheet 20 is wound up. Therefore, it becomes possible to improve manufacturing efficiency and reduce manufacturing cost.

  Furthermore, the heat generating plate 10 shown in FIG. 3 includes a pair of glass plates 11 and 12, a mesh sheet 20 disposed between the pair of glass plates 11 and 12, and the glass plates 11 and 12 and the mesh sheet 20 respectively. And the joining layers 13 and 14 for joining the glass plates 11 and 12 and the mesh sheet 20, and the mesh sheet 20 has a concavo-convex structure layer having a concavo-convex surface 41 formed by the fine protrusions 42. 40 and a conductive mesh 50 formed by a conductive thin wire 51 extending along a valley bottom 44 between the fine protrusions 42 of the concave-convex surface 41 of the concave-convex structure layer 40. The average line width is not less than 5 nm and not more than 500 nm, and the average interval between adjacent minute protrusions is not more than 1000 nm. According to the mesh sheet 20 and the heat generating plate 10 as described above, the average value of the distance between the two adjacent opening regions of the conductive mesh 50 is the same as the average value of the distance between the adjacent minute protrusions 42 of the concavo-convex structure layer 40. obtain. Therefore, it is possible to easily produce the conductive mesh 50 in which the average line width of the conductive thin wires 51 is 5 nm or more and 500 nm or less, and the average interval between adjacent opening regions is 1000 nm or less. Further, according to the mesh sheet 20 and the heat generating plate 10 as described above, the reflection at the interface between the bonding layer 13 and the uneven structure layer 40 is suppressed by including the uneven structure layer 40 having a so-called moth-eye structure. Therefore, the transmittance of the mesh sheet 20 and the heat generating plate 10 can be effectively improved.

  Next, with reference to FIGS. 19-23, the modification of the manufacturing method of the heat generating plate 10 is demonstrated. 19-23 is sectional drawing which shows the modification of the manufacturing method of the heat generating plate 10 in order.

  First, the 1st intermediate body 120 shown in FIG. 19 is produced. The first intermediate 120 has a sheet-like base material 130, an uneven structure layer 140 provided on the base material 130, and a conductive mesh 150 provided on the uneven surface 141 of the uneven structure layer 140. doing. The base material 130 functions as a base material that supports the uneven structure layer 140 and the conductive mesh 150. In addition, the base material 130 is not an essential component in the first intermediate 120 and may be omitted.

  The concavo-convex structure layer 140 has a concavo-convex surface 141 formed by a large number of microprojections 142 arranged at an average interval of 1000 nm or less. Then, the conductive thin wires 151 forming the conductive mesh 150 extend along the valley bottom portion 144 between the minute protrusions 142 in the concavo-convex surface 141 of the concavo-convex structure layer 140. Accordingly, the first intermediate 120 shown in FIG. 19 includes the uneven surface 121 corresponding to the unevenness of the uneven surface 141 of the uneven structure layer 140. The unevenness of the uneven surface 121 of the first intermediate 120 is formed by the microprojections 122 formed corresponding to the microprojections 142 forming the uneven surface 141 of the uneven structure layer 140. Further, the conductive fine wires 151 forming the conductive mesh 150 formed on the valley bottom portion 144 of the concavo-convex structure layer 140 define a large number of opening regions 155 corresponding to the large number of microprojections 142, respectively. Therefore, the average of the interval between the two adjacent opening regions 155 is the same as the average of the arrangement interval of the microprojections 142. That is, the average interval between two adjacent opening regions 155 is 1000 nm or less. The average line width of the conductive thin wires 151 is not less than 5 nm and not more than 500 nm.

  Such a first intermediate 120 can be produced by the same method using the same material as that of the mesh sheet 20 described above. However, the base material 130 and the concavo-convex structure layer 140 may be made of a material that does not have optical transparency.

  Next, as illustrated in FIG. 20, an uncured and liquid resin that forms a bonding layer 113 described later is applied on the uneven surface 121 of the first intermediate body 120. As a result, the resin enters the fine irregularities of the irregular surface 121 of the first intermediate 120. In this state, the resin is temporarily cured by heating, irradiation with ionizing radiation, or the like, so that a resin layer 165 that forms the bonding layer 113 is formed. The uncured resin that forms the bonding layer 113 is not limited to the above-described liquid resin, and a sheet-like (plate-like, film-like) uncured resin may be used on the uneven surface 121 of the first intermediate body 120. The sheet-shaped resin may be pressed against the first intermediate body 120 so that the resin enters the fine unevenness of the uneven surface 121 of the first intermediate body 120. Thereafter, the sheet-like uncured resin may be temporarily cured.

  Then, the 2nd intermediate body 160 shown in FIG. 21 is obtained by removing the base material 130 and the uneven structure layer 140. FIG. For example, when an adhesion lowering layer such as a release layer is formed on the uneven surface 141 of the uneven structure layer 140 and the conductive mesh 150 and the resin layer 165 are formed on the adhesion lowering layer, the substrate 130 and the unevenness are formed. The structure layer 140 can be peeled off and removed by the adhesion lowering layer. In addition, the substrate 130 and the uneven structure layer 140 may be dissolved and removed.

  The second intermediate 160 has a resin layer 165 that forms a bonding layer 113 described later and a conductive thin wire 151 that forms the conductive mesh 150. In the illustrated example, the second intermediate 160 has an uneven surface 161 that is complementary to the uneven surface 141 of the uneven structure layer 140. That is, the concavo-convex surface 161 has a large number of minute recesses 162 that are complementary to the minute protrusions 142 corresponding to the number of minute protrusions 142 of the concavo-convex surface 141 of the uneven structure layer 140. Therefore, the average arrangement interval of the minute recesses 162 is the same as the average arrangement interval of the minute protrusions 142 of the concavo-convex structure layer 140. That is, the average of the arrangement interval of the minute recesses 162 is 1000 nm or less. The uneven surface 161 has a ridge line portion 164 that is complementary to the valley bottom portion 144 corresponding to the valley bottom portion 144 of the uneven surface 141 of the uneven structure layer 140. Then, conductive thin lines 151 forming the conductive mesh 150 are formed on the ridge line portions 164 of the uneven surface 161. In addition, the conductive fine wires 151 forming the conductive mesh 150 and formed on the ridge line portions 164 of the second intermediate body 160 define a large number of opening regions 155 corresponding to the large number of minute recesses 162, respectively.

  Thereafter, the glass plate 111, the second intermediate body 160, the bonding layer 114, and the glass plate 112 are superposed in this order, and heated and pressurized. At this time, the resin layer 165 of the second intermediate body 160 functions as a bonding layer 113 for bonding the glass plate 111 and the conductive mesh 150. In the example shown in FIG. 22, the bonding layer 114 is temporarily bonded to the glass plate 112. Next, the uneven surface 161 of the second intermediate body 160 faces the glass plate 112 to which the bonding layer 114 is temporarily bonded, and the side of the glass plate 112 to which the bonding layer 114 is temporarily bonded is the second intermediate body 160. The glass plate 111, the second intermediate 160, and the glass plate 112 on which the bonding layer 114 is temporarily bonded are overlapped in this order so as to face each other, and heated and pressurized. Thereby, the glass plate 111, the conductive mesh 150, and the glass plate 112 are joined through the joining layer 113 (resin layer 165) and the joining layer 114, and the heat generating plate 110 shown in FIG. 23 is manufactured.

  The heat generating plate 110 shown in FIG. 23 includes a pair of glass plates 111 and 112, a conductive mesh 150 disposed between the pair of glass plates 111 and 112, and the glass plates 111 and 112 and the conductive mesh 150. And the bonding layers 113 and 114 for bonding the glass plates 111 and 112 and the conductive mesh 150 to each other, and the conductive mesh 150 includes a conductive thin wire 151 that defines a large number of opening regions 155. The average line width of the conductive thin wires 151 is 5 nm or more and 500 nm or less, and the average interval between adjacent opening regions 155 is 1000 nm or less. According to such a conductive mesh 150 and the heat generating plate 110, it is difficult to resolve the conductive mesh 150 with human eyes. That is, the conductive mesh 150 can be effectively avoided from being visually recognized. Thereby, the permeability | transmittance of the electroconductive mesh 150 can be improved effectively. In addition, the occurrence of shading unevenness due to the visual recognition of the conductive mesh 150 can be effectively prevented. In addition, since the heat generating plate 110 shown in FIG. 23 does not have a base material or an uneven structure layer that supports the conductive mesh 150, the thickness of the entire heat generating plate 110 can be effectively reduced.

  Note that various modifications can be made to the above-described embodiment.

  For example, the conductive mesh 50 of the mesh sheet 20 may be provided not on the glass plate 11 side surface of the substrate 30 but on the glass plate 12 side surface. Moreover, you may provide in the both surfaces of the glass plate 11 side and the glass plate 12 side of the base material 30. FIG.

  The heat generating plates 10 and 110 may be used for a rear window, a side window, or a sunroof of the automobile 1. Moreover, you may use for windows of vehicles other than a motor vehicle, such as a railway, an aircraft, a ship, and a spacecraft.

  Furthermore, the heat generating plates 10 and 110 can be used not only for vehicles but also for locations that divide indoors and outdoors, such as windows in buildings, stores, and houses.

  In addition, although the some modification with respect to embodiment mentioned above was demonstrated above, naturally, it is also possible to apply combining several modifications suitably.

DESCRIPTION OF SYMBOLS 1 Automobile 5 Front window 7 Power supply 10 Heat generating plate 11 Glass plate 12 Glass plate 13 Joining layer 14 Joining layer 15 Connection part 16 Wiring part 20 Mesh sheet 21 Uneven surface 22 Minute protrusion 30 Base material 40 Uneven structure layer 41 Uneven surface 42 Minute protrusion 43 Top 44 Valley bottom 46 Uneven surface 50 Conductive mesh 51 Conductive thin wire 52 Line portion 55 Open area 58 Metal thin film 92 Die 93 Roll plate 94 Pressing roller 95 Peeling roller 110 Heating plate 111 Glass plate 112 Glass plate 113 Bonding layer 114 Bonding Layer 120 First intermediate body 121 Uneven surface 122 Microprojection 130 Base material 140 Uneven structure layer 141 Uneven surface 142 Microprojection 144 Valley bottom 150 Conductive mesh 151 Conductive fine wire 155 Opening area 160 Second intermediate 161 Uneven surface 162 Microrecess 164 Ridge part 165 Resin layer

Claims (6)

A conductive mesh used for a heating plate that generates heat when a voltage is applied,
The conductive mesh has conductive thin wires that define a large number of open areas;
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
The conductive mesh whose average of the space | interval of an adjacent opening area | region is 1000 nm or less. A mesh sheet used for a heating plate that generates heat when a voltage is applied,
The conductive mesh according to claim 1;
A mesh sheet comprising: a base material that supports the conductive mesh. A mesh sheet used for a heating plate that generates heat when a voltage is applied,
The mesh sheet is
An uneven structure layer having an uneven surface formed by minute protrusions;
A conductive mesh formed by conductive thin wires extending along the bottom of the concave and convex surfaces of the concave and convex structure layer and between the microprotrusions, and
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
The mesh sheet whose average of the space | interval of adjacent microprotrusion is 1000 nm or less. A heating plate that generates heat when a voltage is applied,
A pair of glass plates;
A conductive mesh disposed between the pair of glass plates;
A bonding layer disposed between each glass plate and the conductive mesh and bonding the glass plate and the conductive mesh; and
The conductive mesh has conductive thin wires that define a large number of open areas;
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
A heat generating plate having an average interval between adjacent opening regions of 1000 nm or less. A heating plate that generates heat when a voltage is applied,
A pair of glass plates;
A mesh sheet disposed between the pair of glass plates;
A bonding layer disposed between each glass plate and the mesh sheet and bonding the glass plate and the mesh sheet; and
The mesh sheet has a base material and a conductive mesh provided on the base material,
The conductive mesh has conductive thin wires that define a large number of open areas;
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
A heat generating plate having an average interval between adjacent opening regions of 1000 nm or less. A heating plate that generates heat when a voltage is applied,
A pair of glass plates;
A mesh sheet disposed between the pair of glass plates;
A bonding layer disposed between each glass plate and the mesh sheet and bonding the glass plate and the mesh sheet; and
The mesh sheet is formed by a concavo-convex structure layer having a concavo-convex surface formed by fine protrusions, and a conductive thin wire extending along a valley bottom portion between the microprotrusions of the concavo-convex surface of the concavo-convex structure layer. A conductive mesh,
The average line width of the conductive thin wires is 5 nm or more and 500 nm or less,
A heat generating plate having an average interval between adjacent minute protrusions of 1000 nm or less.