JP6516143B2 - Vehicle with heat generating plate, conductive pattern sheet and heat generating plate - Google Patents

Description

  The present invention relates to a heat generating plate, a conductive pattern sheet, and a vehicle provided with the heat generating plate.

  Heretofore, as a defroster apparatus used for window glass of a front window or a rear window of a vehicle, one in which a heating wire made of tungsten wire is disposed over the entire window glass is known (see, for example, patent documents 1 and 2) ). In this prior art, the heating wire disposed throughout the window glass is energized, and the resistance heating causes the window glass to rise in temperature to remove fogging of the window glass or melt snow or ice adhering to the window glass. Or, evaporation of water droplets can ensure the visibility of the occupant.

JP, 2013-173402, A Japanese Patent Application Laid-Open No. 8-72674

  As mentioned above, in the prior art defroster apparatus, a tungsten wire is used as the heating wire. In this case, in order to prevent the electrical resistance of the heating wire from becoming too high due to the high electrical resistivity of tungsten, the cross-sectional area of the heating wire is increased. Therefore, the heating wire using a tungsten wire is easily viewed by the observer. The fact that the heating wire is viewed by an observer such as a driver deteriorates the visibility of the observer through the window glass.

  The present invention has been made in consideration of these points, and it is an object of the present invention to improve the invisibility of heating wire of a defroster apparatus.

The heating plate according to the present invention is
A pair of glass plates,
A conductive pattern disposed between the pair of glass plates and including a conductive thin wire;
A bonding layer disposed between the conductive pattern and at least one of the pair of glass plates;
The conductive thin line is
In a cross section orthogonal to the extending direction of the conductive thin line, a middle portion along the normal direction of the heat generating plate has a narrow portion,
It has a first wide portion having a larger width than the narrow portion on one side of the pair of glass plates of the narrow portion along the normal direction of the heat generating plate,
A second wide portion having a larger width than the narrow portion is provided on the other side of the pair of glass plates of the narrow portion along the normal direction of the heat generating plate.

In the heat generating plate according to the present invention, the minimum width of the narrow portion of the conductive thin line is W _min (μm), the maximum width of the first wide portion is W _amax (μm), and the second wide portion The relationship between the following (a) and (b) may be satisfied, where W _bmax (μm) is the maximum width of
W _amax −W _min ≦ 10 (a)
W _bmax −W _min ≦ 10 (b)

In the heat generating plate according to the present invention, when the maximum width of the first wide portion of the conductive thin line is W _amax (μm) and the maximum width of the second wide portion is W _bmax (μm), The relationship of (c) may be satisfied.
W _amax ≦ W _bmax (c)

In the heat generating plate according to the present invention, when the maximum width of the first wide portion of the conductive thin line is W _amax (μm) and the maximum width of the second wide portion is W _bmax (μm), The relationship of (d) may be satisfied.
| W _amax −W _bmax | = 0 (d)

  In the heat generating plate according to the present invention, the conductive pattern may be formed by patterning a conductive layer by etching.

  In the heat generating plate according to the present invention, the conductive pattern has a pattern defining a plurality of opening areas, and the conductive pattern extends between two branch points to define a plurality of opening areas. It may include a connection element.

  In the heating plate according to the present invention, in the conductive pattern, an average of the number of the connection elements extending from one branch point may be more than 3.0 and less than 4.0.

  In the heat generating plate according to the present invention, the conductive pattern includes open regions respectively surrounded by four, five, six and seven connecting elements, and the open regions included in the conductive pattern Among them, the open area surrounded by the six connection elements may be the largest.

  In the heat generating plate according to the present invention, at least a part of the plurality of connection elements may have a curved or broken line shape as viewed from the normal direction of the plate surface of the heat generating plate.

The conductive pattern sheet according to the present invention is
A substrate,
And a conductive pattern provided on the substrate and including a conductive thin wire,
The conductive thin line is
In a cross section orthogonal to the extending direction of the conductive thin line, a middle portion along the normal direction of the conductive pattern sheet has a narrow portion,
It has a first wide portion having a larger width than the narrow portion on the base side of the narrow portion along the normal direction of the conductive pattern sheet,
A second wide portion having a larger width than the narrow portion is provided on the side of the narrow portion opposite to the base along the normal direction of the conductive pattern sheet.

  A vehicle according to the present invention comprises the heat generating plate described above.

  According to the present invention, the invisibility of the conductive pattern of the defroster device can be improved.

FIG. 1 is a view 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 equipped with 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. FIG. 3 is a cross-sectional view of the heat generating plate of FIG. FIG. 4 is a plan view showing an example of the pattern shape of the conductive pattern of the heat generating plate. FIG. 5 is a plan view showing another example of the pattern shape of the conductive pattern of the heat generating plate. FIG. 6 is a diagram showing a part of the conductive pattern of FIG. 5 in an enlarged manner. FIG. 7 is a cross-sectional view showing the cross-sectional shape of the conductive thin wire of the conductive pattern. FIG. 8 is a view for explaining an example of a method of manufacturing a heat generating plate. FIG. 9 is a figure for demonstrating an example of the manufacturing method of a heat-generating plate. FIG. 10 is a diagram for explaining an example of a method of manufacturing a heat generating plate. FIG. 11 is a figure for demonstrating an example of the manufacturing method of a heat-generating plate. FIG. 12 is a figure for demonstrating an example of the manufacturing method of a heat-generating plate. FIG. 13 is a figure for demonstrating an example of the manufacturing method of a heat-generating plate. FIG. 14 is a figure for demonstrating an example of the manufacturing method of a heat-generating plate. FIG. 15 is a figure for demonstrating the modification of the manufacturing method of a heat-generating plate. FIG. 16 is a figure for demonstrating the modification of the manufacturing method of a heat-generating plate. FIG. 17 is a view for explaining a modification of the method of manufacturing the heat generating plate. FIG. 18 is a view for explaining a modified example of the method of manufacturing the heat generating plate. FIG. 19 is a figure for demonstrating the modification of the manufacturing method of a heat-generating plate. FIG. 20 is a view for explaining another modified example of the method of manufacturing the heat generating plate. FIG. 21 is a figure for demonstrating the other modification of the manufacturing method of a 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 easy illustration and understanding, the scale, the dimensional ratio in the vertical and horizontal directions, etc. are appropriately changed from those of the actual one and exaggerated.

  In the present specification, the terms "plate", "sheet" and "film" are not distinguished from one another based only on the difference in designation. For example, "conductive pattern sheet" is a concept including a member that may be called a plate or a film, and thus "conductive pattern sheet" is a "conductive pattern plate (substrate)" or "conductive pattern". It can not be distinguished only by the difference of a name and the member called film.

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

  In the present specification, the term "joining" includes not only "main joining" which completely completes joining, but also so-called "temporary joining" for temporarily fixing before "main joining".

  In addition, as used herein, the terms such as “parallel”, “orthogonal”, “identical”, values of length and angle, etc., which specify the shape and geometrical conditions and their degree, etc. Without being bound by the meaning, it shall be interpreted including the extent to which the same function can be expected.

  1 to 20 are views for explaining an embodiment according to the present invention. Among these, FIG. 1 is a view schematically showing an automobile provided with a heat generating plate, FIG. 2 is a view of the heat generating plate as viewed from the normal direction of the plate surface, and 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 glass such as a front window, a rear window, and a side window. Here, an example in which the front window 5 is constituted by the heat generating plate 10 is exemplified. In addition, the automobile 1 has a power source 7 such as a battery.

  FIG. 2 shows the heat generating plate 10 as viewed in 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. In the example shown in FIG. 3, the heat generating plate 10 is electrically conductive between the pair of glass plates 11 and 12, the conductive pattern sheet 20 disposed between the pair of glass plates 11 and 12, and the glass plates 11 and 12. And bonding layers 13 and 14 for bonding to the base pattern sheet 20. In the example shown in FIGS. 1 and 2, the heat generating plate 10 is curved, but in FIGS. 3 and 13 to 20, the heat generating plate 10 and the heat generating plate 10 are illustrated in order to simplify the illustration and facilitate the understanding. The glass plates 11 and 12 are illustrated in flat form.

  The conductive pattern sheet 20 is for conducting electricity to the sheet-like base material 30, the holding layer 31 laminated on the base material 30, the conductive pattern 40 formed on the holding layer 31, and the conductive pattern 40. And a connecting portion 16 (also referred to as a bus bar or a bus bar electrode) for connecting the conductive pattern 40 and the wiring portion 15.

  In the example shown in FIGS. 2 and 3, the conductive pattern 40 is energized from the power source 7 such as a battery via the wiring portion 15 and the connection portion 16 made of copper wire or the like, and the conductive pattern 40 is heated by resistance heating. Let The heat generated by the conductive pattern 40 is transmitted to the glass plates 11 and 12 through the bonding layers 13 and 14 to warm the glass plates 11 and 12. As a result, it is possible to remove the fogging due to condensation adhering to the glass plates 11 and 12. Moreover, when snow or ice adheres to the glass plates 11 and 12, the snow and ice can be melted. Therefore, the visibility of the occupant is well secured. In addition, although illustration is abbreviate | omitted, a switch is normally inserted between the power supply 7 and the connection part (bus-bar) 16 of the conductive pattern 40 in the wiring part 15 (serially connected). Then, only when the heating plate 10 needs to be heated, the switch is closed to energize the conductive pattern 40.

  In particular, when the glass plates 11 and 12 are used for a front window of a car, it is preferable to use a glass plate having a high visible light transmittance so as not to obstruct the view of the occupant. Examples of materials of such glass plates 11 and 12 include soda lime glass (blue sheet glass), borosilicate glass (white sheet glass), quartz glass, soda glass, potassium glass and the like. The glass plates 11 and 12 preferably have a transmittance of 90% or more in the visible light region. Here, the visible light transmittance of the glass plates 11 and 12 is measured in the range of a measurement wavelength of 380 nm to 780 nm using a spectrophotometer ("UV-3100PC" manufactured by Shimadzu Corporation, a product conforming to JIS K 0115). It is specified as the average value of the transmittance at each wavelength. The visible light transmittance may be lowered by coloring the glass plates 11 and 12 partially or entirely. In this case, it is possible to block the direct sunlight and to make it difficult to visually identify the inside of the vehicle from the outside.

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

  The glass plates 11 and 12 and the conductive pattern sheet 20 are bonded via bonding layers 13 and 14, respectively. As such bonding layers 13 and 14, layers made of materials having various adhesiveness or adhesiveness can be used. In addition, it is preferable that the bonding layers 13 and 14 have high visible light transmittance. As a typical bonding layer, a layer made of polyvinyl butyral (PVB) can be exemplified. The thickness of each of the bonding layers 13 and 14 is preferably 0.15 mm or more and 0.7 mm or less.

  In addition, 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. Also, one functional layer may exhibit two or more functions, and, for example, the glass plates 11 and 12 of the heat generating plate 10, the bonding layers 13 and 14, and the base material of the conductive pattern sheet 20 described later. A function may be given to at least one of the thirty. Examples of functions that can be imparted to the heat generating plate 10 include an antireflection (AR) function, a hard coat (HC) function having scratch resistance, an infrared ray shielding (reflection) function, an ultraviolet ray shielding (reflection) function, and a polarization function. , Antifouling function, etc. can be exemplified.

  Next, the conductive pattern sheet 20 will be described. The conductive pattern sheet 20 is for conducting electricity to the sheet-like base material 30, the holding layer 31 laminated on the base material 30, the conductive pattern 40 formed on the holding layer 31, and the conductive pattern 40. And a connection portion 16 for connecting the conductive pattern 40 and the wiring portion 15. The conductive pattern sheet 20 may have a plane dimension substantially the same as that of the glass plates 11 and 12 and may be disposed over the entire heating plate 10, or may be a part of the heating plate 10 such as a front portion of a driver's seat. It may be arranged only.

  The sheet-like substrate 30 functions as a substrate for supporting the holding layer 31 and the conductive pattern 40. The substrate 30 is an electrically insulating substrate which is generally transparent and transmits a wavelength (380 nm to 780 nm) in the visible light wavelength band. In the example shown in FIGS. 2, 4 and 5, the base material 30 has substantially the same dimensions as the glass plates 11 and 12 and has a substantially trapezoidal planar shape.

  Any resin may be used as the resin contained in the base material 30 as long as it transmits visible light and can appropriately support the holding layer 31 and the conductive pattern 40. Preferably, a thermoplastic resin can be used. . Examples of the thermoplastic resin include acrylic resins such as polymethyl methacrylate, polyester resins such as polyvinyl chloride, polyethylene terephthalate (PET), amorphous polyethylene terephthalate (A-PET), polyethylene naphthalate (PEN), polyethylene, polypropylene And polyolefin resins such as polymethylpentene and cyclic polyolefin, cellulose resins such as triacetyl cellulose (cellulose triacetate), polystyrene, polycarbonate resin, AS resin and the like. Among them, acrylic resin and polyvinyl chloride are preferable because they are excellent in etching resistance, weather resistance and light resistance.

  Further, in consideration of the retentivity of the conductive pattern 40, the light transmittance, and the like, the base material 30 preferably has a thickness of 0.03 mm or more and 0.3 mm or less.

  The holding layer 31 has a function of improving the bonding between the base 30 and the conductive pattern 40 and holding the conductive pattern 40. The holding layer 31 can be formed, for example, by laminating a transparent electrically insulating resin sheet on the substrate 30, or can be formed by applying a resin material on the substrate 30. As such a holding layer 31, for example, polyvinyl butyral (PVB), a two-component curable urethane adhesive, a two-component curable epoxy adhesive, or the like can be used. Further, as described later, when the substrate 30 is peeled off after the conductive pattern sheet 20 is bonded (temporarily bonded) to the glass plate 11 through the bonding layer 13, the holding layer 31 is made to include the peeling layer. It is also good. In addition, the thickness of the holding layer 31 can be set to 1 μm or more and 100 μm or less in consideration of light transmittance, bonding property of the base 30 and the conductive pattern 40, and the like. Preferably, the thickness of the holding layer 31 can be 1 μm or more and 15 μm or less.

  The conductive pattern 40 will be described with reference to FIGS. 4 to 6. FIGS. 4 and 5 are both plan views of the conductive pattern sheet 20 as viewed from the normal direction of the sheet surface. FIG. 6 is an enlarged view of a part of the conductive pattern 40 of FIG.

  The conductive pattern 40 is energized from a power source 7 such as a battery via the wiring portion 15 and the connection portion 16 and generates heat due to resistance heating. Then, the heat is transmitted to the glass plates 11 and 12 through the bonding layers 13 and 14 to warm the glass plates 11 and 12.

  An example of the pattern shape of the conductive pattern 40 is shown in FIG. In the example shown in FIG. 4, a plurality of conductive thin wires 50 connecting the pair of connection portions 16 is provided. In the illustrated example, the plurality of conductive thin wires 50 extend from one connecting portion 16 to the other connecting portion 16 respectively in a wavy pattern. The plurality of conductive thin wires 50 are arranged apart from each other in a direction that is not parallel to the extending direction of the conductive thin wires 50. In particular, the plurality of conductive thin wires 50 are arranged in a direction orthogonal to the extending direction of the conductive thin wires 50. Each of the conductive thin wires 50 may extend between the pair of connection portions 16 in a linear, polygonal or sinusoidal pattern, in addition to the wavy pattern.

  5 and 6 show other examples of the pattern shape of the conductive pattern 40. FIG. In the example shown in FIGS. 5 and 6, the conductive thin wires 50 of the conductive pattern 40 are arranged in a mesh-like pattern that defines a large number of open regions 42. The conductive pattern 40 includes a plurality of connection elements 43 extending between the two branch points 41 and defining an open area 42. That is, the conductive thin wires 50 of the conductive pattern 40 are configured as a collection of a large number of connection elements 43 forming the branch points 41 at both ends.

  In the example shown in FIGS. 5 and 6, the large number of open areas 42 of the conductive pattern 40 are arranged in a shape and pitch in which the arrangement of unit cells does not have repetitive regularity (periodic regularity). Particularly, in the illustrated example, a large number of open regions 42 correspond to each Voronoi region in the Voronoi diagram generated from random two-dimensional distributed birth points distributed within certain upper and lower limits between adjacent birth point distances. It is arranged as follows. In other words, each connection element 43 of the conductive pattern 40 coincides with each boundary of the Voronoi region in the specific Voronoi diagram. Further, each branch point 41 of the conductive pattern 40 matches the Voronoi point in the Voronoi diagram. In addition, since this Voronoi diagram is obtained by a known method as disclosed in, for example, JP 2012-178556 A, JP 2013-238029 A etc., the detailed description of the method of creating the Voronoi diagram is as follows. The description is omitted.

  When the conductive pattern has a large number of open areas arranged in a shape and a pitch having repetitive regularity (periodic regularity) such as a square lattice arrangement or a honeycomb arrangement, the repetition rule of the arrangement of the large number of open areas Due to sex, light spots may be visible. For example, when light from the headlight of an oncoming car is incident on the front window of a car, light is incident on the heat generating board from the side opposite to the viewer, for example, when the light enters the front window of the car. This phenomenon is observed when the light is dispersed in the pattern of the above-mentioned light, and in particular, when a large number of open areas of the conductive pattern are arranged in a repetitively regular shape and pitch, the light tends to be noticeable . Then, the fact that the light source is viewed by an observer such as a driver deteriorates the visibility of the observer through the heating plate. On the other hand, as shown in FIGS. 5 and 6, according to the conductive pattern 40 having a large number of open areas 42 arranged in a shape and pitch not having repetitive regularity (periodic regularity), heat generation is achieved. The generation of light on the plate 10 can be effectively suppressed.

  In the thirty conductive patterns 40 shown in FIGS. 5 and 6, the average number of connection elements 43 extending from one branch point 41 is greater than 3.0 and less than 4.0. Thus, when the average of the number of connection elements 43 extending from one branch point 41 is greater than 3.0 and less than 4.0, it is possible to obtain a pattern in which regularity is broken from the honeycomb arrangement. When the average of the number of connection elements 43 extending from one branch point 41 is greater than 3.0 and less than 4.0, the arrangement of the opening areas 42 is disordered to make the opening areas 42 repeat regularity (period As a result, it is possible to stably prevent the direction in which the components are arranged side by side from being present, and as a result, it is possible to more effectively suppress the generation of light in the heating plate 10. At the same time, since the arrangement of the connection elements 43 is based on the honeycomb arrangement, the connection elements 43 are uniformly dispersed, and as a result, it is possible to effectively suppress the heat generation unevenness.

  In addition, the average of the number of connection elements 43 extending from one branch point 41 is strictly determined by examining the number of connection elements 43 extending for all the branch points 41 included in the conductive pattern 40. However, in practice, the connection extending out from one branch point 41 taking into consideration the size of the open area 42 per one area defined by the conductive thin line 50, etc. Within a section having an area expected to reflect the overall tendency of the number of elements 43, for a number of branch points 41 considered to be appropriate considering the degree of variation in the number of objects to be investigated: The number of connection elements 43 extending from each branch point 41 is examined to calculate an average value thereof, and the calculated value is an average value of the number of connection elements 43 extending from one branch point 41 for the conductive pattern 40. Treat as Unishi may be. For example, the average value calculated by counting the number of connection elements 43 extending from the 100 branch points 41 included in the 300 mm × 300 mm region of the conductive pattern 40 using an optical microscope or an electron microscope is the conductive value. It can be treated as an average value of the number of connection elements 43 extending from one branch point 41 for the sex pattern 40.

  In the conductive pattern 40 shown in FIGS. 5 and 6, the conductive pattern 40 includes open regions 42 surrounded by four, five, six and seven connecting elements 43, respectively, and conductive Among the open areas 42 included in the sex pattern 40, the open area 42 surrounded by the six connection elements 43 is the largest. That is, more open areas 42 surrounded by six connecting elements 43 are included in the conductive pattern 40 as compared to the open areas 42 surrounded by another number of connecting elements 43. There is.

  In such a conductive pattern 40, the arrangement of the opening areas 42 is an arrangement in which the regularity of the shape and arrangement of each opening area is broken, in other words, a honeycomb arrangement in which regular hexagons of the same shape are regularly arranged. The shape and arrangement of each opening area can be randomized in reference to the honeycomb arrangement. As a result, it is possible to suppress the occurrence of apparent coarseness and density in the arrangement of the opening regions 42, and it is possible to distribute a large number of the opening regions 42 with a substantially uniform density, that is, a substantially uniform distribution. As a result, heat generation unevenness can be effectively suppressed. In addition, it is stably possible to completely disorder the arrangement of the opening areas 42, that is, to prevent the direction in which the opening areas 42 are regularly arranged. Therefore, the generation of light in the heat-generating plate 10 can be further effectively suppressed.

  Note that the number of connection elements 43 surrounding one opening area 42 is strictly the number of connection elements 43 surrounding the opening area 42 for all the opening areas 42 included in the conductive pattern 40. However, practically, the total number of connection elements 43 surrounding one open area 42 is taken into consideration, taking into consideration the size of the open area 42 per one defined by the conductive thin line 50, etc. Surrounding each open area 42 for an open area 42 which is considered to be appropriate in consideration of the degree of variation in the number of objects to be examined in one section having an area expected to reflect the general tendency The number of connection elements 43 may be determined, and the number of opening areas 42 for each number of connection elements 43 surrounding the periphery may be integrated. For example, the number of connection elements 43 surrounding each of the 100 opening areas 42 included in the 300 mm × 300 mm area of the conductive pattern 40 is counted using an optical microscope or an electron microscope, and About the said electroconductive pattern 40 using the value which integrated the number of the opening area | regions 42 for every number. It can be determined how many open areas 42 surrounded by the number of connection elements 43 are the largest.

  In addition, as a material for forming such a conductive pattern 40, for example, metals such as gold, silver, copper, platinum, aluminum, chromium, molybdenum, nickel, titanium, palladium, indium, tungsten, and nickel, and nickel -One or more alloys of two or more metals selected from alloys of these exemplified metals such as chromium alloy, brass, bronze and the like can be exemplified.

  Next, the cross-sectional shape of the conductive thin wire 50 of the conductive pattern 40 will be described with reference to FIG. FIG. 7 is an enlarged view of a cross section of the conductive pattern sheet 20 corresponding to the line AA in FIG. 4 and FIG. 5.

  In the example shown in FIG. 7, the conductive pattern sheet 20 includes a sheet-like base 30, a holding layer 31 stacked on the base 30, and a conductive pattern 40 formed on the holding layer 31. have. The conductive thin wire 50 is opposed to the base end face 50b and the base end face 50b forming the surface on the base 30 side in a cross section (hereinafter also referred to as a main cutting surface) orthogonal to the extending direction (longitudinal direction) of the conductive thin wire 50 And the side surfaces 50c and 50d connecting the distal end surface 50a and the proximal end surface 50b. In the present embodiment, the distal end surface 50a of the conductive thin wire 50 forms a first surface finally facing one of the pair of glass plates 11 and 12 of the heat generating plate 10, and the proximal end surface of the conductive thin wire 50 A second surface 50 b finally faces the other of the pair of glass plates 11 and 12 of the heat generating plate 10.

In the example shown in FIG. 7, the first surface (tip surface) 50 a and the second surface (base end surface) 50 b of the conductive thin wire 50 are parallel to each other. One side surface 50 c of the conductive thin wire 50 is parallel to the sheet surface (plate surface of the heat generating plate 10) of the conductive pattern sheet 20 on the first surface (tip surface) 50 a and orthogonal to the extending direction of the conductive thin wire 50. End A along one direction (hereinafter also referred to as the width direction of the conductive thin wire 50) and end B along the width direction of the conductive thin wire 50 in the second surface (base end face) 50b When, and has a shape which is concave inward from the straight line L ₁ connecting the (other side surface 50d side). Similarly, the other side surface 50d of the conductive thin wire 50 is the end C of the other side along the width direction of the conductive thin wire 50 in the first surface (tip end surface) 50a and the second surface (base end surface) 50b. and the end D of the other side along the width direction of the electroconductive thin line 50, the straight line L ₂ connecting the has a shape which is concave inward (one side face 50c side). As a result, the conductive thin line 50 has a generally hourglass shape as a whole on the main cut surface.

  More specifically, one side surface 50c of the conductive thin wire 50 is first inclined toward the other side surface 50d from the second surface (base end surface) 50b side toward the first surface (tip surface) 50a side. , And then slope away from the other side 50d. In addition, the other side surface 50d of the conductive thin wire 50 is first inclined toward the one side surface 50c from the second surface (base end surface) 50b side toward the first surface (tip surface) 50a side, and then, It inclines away from one side 50c.

In the example shown in FIG. 7, the conductive thin line 50 has a width having the minimum width W _min at the intermediate portion 51 along the normal direction of the sheet surface of the conductive pattern sheet 20 (plate surface of the heat generating plate 10). A narrow portion 55 is formed. The width of the conductive thin line 50 changes so as to increase from the middle portion 51 to the first surface (tip surface) 50 a side. Thus, a first wide portion 56 having a width larger than the narrow portion 55 is formed on the intermediate portion 51 to the first surface (tip surface) 50 a side. In the illustrated example, in the area 52 near the first surface (tip surface) side along the normal direction of the sheet surface (plate surface of the heat generating plate 10) of the conductive pattern sheet 20, the first wide portion 56 is It has a large _Wamax . In particular, in the illustrated example, the maximum width W _amax of the first wide portion 56 matches the width of the conductive thin wire 50 on the first surface (tip surface) 50 a. In addition, the width of the conductive thin line 50 changes so as to increase from the middle portion 51 toward the second surface (base end surface) 50 b. Thus, a second wide portion 57 having a width larger than the narrow portion 55 is formed on the intermediate portion 51 to the first surface (tip surface) 50 a side. In the illustrated example, the second wide portion 57 is the furthest in the area 53 near the second surface (base end surface) along the normal direction of the sheet surface (plate surface of the heat generating plate 10) of the conductive pattern sheet 20 _Has significant W _bmax . Particularly in the illustrated example, the maximum width W _bmax of the second wide portion 57 matches the width of the conductive thin wire 50 on the second surface (base end surface) 50 b.

  Here, “the first surface (tip surface) side vicinity region 52” of the conductive thin wire 50 refers to the sheet surface of the conductive pattern sheet 20 on the first surface (tip surface) 50 a side of the conductive thin wire 50 It refers to a region having a thickness corresponding to 20 to 50% of the height (thickness) H along the normal direction of the plate surface of the heat-generating plate 10. Further, “the second surface (base end face) side vicinity region 53” of the conductive thin wire 50 means the sheet surface (heat generation of the conductive pattern sheet 20 on the second face (base end face) 50b side of the conductive thin wire 50). It refers to a region having a thickness corresponding to 20 to 50% of the height (thickness) H along the normal direction of the plate surface of the plate 10. Furthermore, the “intermediate portion 51” of the conductive thin wire 50 is the first surface (tip) along the normal direction of the sheet surface (plate surface of the heat generating plate 10) of the conductive thin film 50. It refers to an intermediate region sandwiched between the surface near region 52 and the second surface (base end face) side near region 53.

In the conductive pattern 40 having such a configuration, the minimum width W _min of the conductive thin wire 50 can be set to 4 μm or more and 10 μm or less. Further, the maximum width W _amax of the first wide portion 56 of the conductive thin wire 50 can be 5 μm or more and 15 μm or less. The maximum width W _bmax of the second wide portion 57 of the conductive thin wire 50 can be 5 μm to 15 μm. The height H of the conductive fine wire 50, that is, the height H along the normal direction of the sheet surface of the conductive pattern sheet 20 (plate surface of the heat generating plate 10) can be 2 μm or more and 17 μm or less. Furthermore, the cross-sectional area of the conductive thin wire 50 can be 7 μm ² or more and 150 μm ² or less. According to the conductive pattern 40 having the conductive thin line 50 of such a size, the conductive thin line 50 is sufficiently thin, so that the conductive pattern 40 can be effectively made invisible and sufficient. Conductivity can be secured.

In the example shown in FIGS. 3 and 7, the maximum width W _bmax of the second wide portion 57 of the conductive thin wire 50 is larger than the maximum width W _amax of the first wide portion 56 of the conductive thin wire 50. It is getting bigger. That is, the maximum width Wbmax of the second wide portion 57 of the conductive thin wire 50 (the width of the second surface (base end face) 50 b of the conductive thin wire 50) _{Wbmax forms} the maximum width W of the conductive thin wire 50.

In the heat generating plate incorporating the conductive pattern sheet 20 shown in FIG. 7 and the conductive pattern 40 shown in FIG. 7, that is, the heat generating plate 10 shown in FIG. Assuming that the minimum width of 55 is W _min (μm), the maximum width of the first wide part 56 is W _amax (μm), and the maximum width of the second wide part 57 is W _bmax (μm) The relationship between (a) and (b) is satisfied.
W _amax −W _min ≦ 10 (a)
W _bmax −W _min ≦ 10 (b)

  According to the conductive pattern sheet 20 and the heating plate 10 satisfying the relationship of (a) and (b), a cross-sectional area sufficient for obtaining appropriate conductivity while reducing the maximum width W of the conductive thin wire 50 It is possible to secure As a result, it is possible to obtain appropriate conductivity of the conductive pattern 40 while effectively making the conductive pattern 40 invisible.

The conductive pattern sheet 20 shown in FIG. 7 and the heating plate 10 shown in FIG. 3 satisfy the following relationship (c).
W _amax ≦ W _bmax (c)

  According to the conductive pattern sheet 20 and the heat generating plate 10 satisfying the relationship of (c), the conductive pattern 40 can be reliably embedded in the bonding layer 13, and air bubbles are formed at the interface between the conductive pattern 40 and the bonding layer 13. Can be suppressed. Further, the contact area between the conductive pattern 40 and the holding layer 31 can be sufficiently secured, and the adhesion strength between the conductive pattern 40 and the holding layer 31 can be improved.

Furthermore, the conductive pattern sheet 20 shown in FIG. 7 and the heating plate 10 shown in FIG. 3 satisfy the following relationship (d).
| W _amax −W _bmax | = 0 (d)

  According to the conductive pattern sheet 20 and the heating plate 10 satisfying the relationship of (d), a sufficient cross-sectional area is obtained to obtain appropriate conductivity while the maximum width W of the conductive thin wire 50 is further reduced. It becomes possible. As a result, it is possible to obtain appropriate conductivity of the conductive pattern 40 while making the conductive pattern 40 more effectively invisible.

The minimum width W _{min of} the conductive thin wire 50, the maximum width W _amax of the first wide part 56 of the conductive thin wire 50, the maximum width W _bmax of the second wide part 57 of the conductive thin wire 50, the conductive thin wire 50 In terms of each dimension H of the conductive wire 50 and the cross-sectional area of the conductive thin wire 50, practically, in consideration of the size and the like of the opening region 42 per one defined by the conductive thin wire 50, etc. In a section having an area expected to reflect the overall tendency of each dimension and cross-sectional area, it is considered appropriate to take into account the degree of variation in the dimensions and cross-sectional area of the object to be investigated. The dimensions and the cross-sectional area of the conductive thin wire 50 (connection element 43) may be measured. For example, the conductive pattern 40 has dimensions and a cross-sectional area measured using an optical microscope or an electron microscope for 100 places of the conductive thin wire 50 (connection element 43) included in the 300 mm × 300 mm region of the conductive pattern 40. Can be treated as the dimensions and cross-sectional area of the conductive thin wire 50 (connection element 43).

  By the way, in the example shown by FIG. 3 and FIG. 7, the electroconductive thin wire 50 which makes the electroconductive pattern 40 is the electroconductive metal layer 47 and the base 30 opposite side of the electroconductive metal layer 47 (the glass plate 11 side) ) And the first dark layer 48 forming the first surface (tip surface) 50a of the conductive thin wire 50, and the base 30 side (the glass plate 12 side) of the conductive metal layer 47, the conductive thin wire And a second dark layer 49 forming the 50 second surface (base end surface) 50b.

  In the dark color layers 48 and 49, for example, a part of the material forming the conductive metal layer 47 is subjected to a darkening treatment (blackening treatment) to form a metal oxide or metal sulfide in a part forming the conductive metal layer 47. It can be provided by forming a film made of a substance. The conductive metal layer 47 and the dark color layers 48 and 49 have different etching rates, and the dark color layers 48 and 49 cause the conductive metal layer 47 and the dark color layers 48 and 49 to be etched using a photolithography technique described later. The etching rate of the conductive metal layer 47 can be appropriately adjusted. In addition, since the dark color layers 48 and 49 formed by the darkening process (blackening process) have roughened surfaces, the adhesion between the conductive pattern 40 and the bonding layer 13 and the conductive pattern are obtained. The effect of improving the adhesion between the support 40 and the holding layer 31 or the bonding layer 14 can also be exhibited.

  Next, an example of a method of manufacturing the heat generating plate 10 will be described with reference to FIGS. 8-14 is sectional drawing which shows an example of the manufacturing method of the heat-emitting plate 10 in order.

  First, a metal foil 61 is prepared, and on one surface of the metal foil 61, a second dark film 63 which will later form a second dark layer 49 of the conductive thin wire 50 is formed. The metal foil 61 later forms the conductive metal layer 47 of the conductive thin wire 50. As the metal foil 61, for example, metals such as gold, silver, copper, platinum, aluminum, chromium, molybdenum, nickel, titanium, palladium, indium and the like, and metals such as nickel-chromium alloy, brass and the like are exemplified. An alloy foil of two or more selected metals can be used. Moreover, the thickness of the metal foil 61 can be set to 1 μm or more and 15 μm or less. The second dark film 63 is, for example, a film formed of a metal oxide or a metal sulfide on a part of the metal foil 61 by applying a darkening treatment (blackening treatment) to a part of the material forming the metal foil 61 Can be provided.

  Further, the base material 30 is prepared, and the holding layer 31 is formed on one side of the base material 30. As the substrate 30, for example, a thermoplastic resin that transmits visible light can be used. As this thermoplastic resin, for example, acrylic resin such as polymethyl methacrylate, polyester resin such as polyvinyl chloride, polyethylene terephthalate, amorphous polyethylene terephthalate (A-PET), polyethylene resin, polyolefin resin such as polypropylene, triacetyl cellulose ( And cellulose resins such as cellulose triacetate), polystyrene, polycarbonate resin, AS resin and the like. Among them, acrylic resin and polyvinyl chloride are preferable because they are excellent in etching resistance, weather resistance and light resistance. As the holding layer 31, for example, polyvinyl butyral (PVB), a two-component curable urethane adhesive, a two-component curable epoxy adhesive, or the like can be used. The holding layer 31 can be formed, for example, by laminating a sheet-like material on the substrate 30, or can be formed by applying a flowable material on the substrate 30.

  Next, as shown in FIG. 8, the second dark film 63 and the holding layer 31 face each other on the metal foil 61 on which the second dark film 63 is formed and the base 30 on which the holding layer 31 is formed. Stack as you do. At this time, the surface of the second dark-colored film 63 in contact with the holding layer 31 is roughened by the darkening treatment (blackening treatment), so the resin material constituting the holding layer 31 is the second dark-colored film 63. Penetration on the surface of the surface. Therefore, the second dark film 63 and the holding layer 31 are firmly joined by the so-called anchor effect. Thereby, the metal foil 61 and the base material 30 are firmly joined. And the laminated body by which the base material 30, the holding layer 31, the 2nd dark-colored film 63, and the metal foil 61 were laminated | stacked in this order as is shown by FIG. 9 is obtained.

  Next, as shown in FIG. 10, the first dark layer 48 of the conductive thin wire 50 is to be formed on the surface of the metal foil 61 opposite to the second dark film 63. Form a dark film 62 of The first dark film 62 is, for example, a film formed of a metal oxide or a metal sulfide on a part of the metal foil 61 by applying a darkening treatment (blackening treatment) to a part of the material forming the metal foil 61 Can be provided.

  Next, as shown in FIG. 11, a resist pattern 65 is provided on the first dark film 62. The resist pattern 65 is a pattern corresponding to the pattern of the conductive pattern 40 to be formed. In the method described here, the resist pattern 65 is provided only on the place where the conductive pattern 40 is finally formed. The resist pattern 65 can be formed by patterning using a known photolithography technique.

  Next, as shown in FIG. 12, using the resist pattern 65 as a mask, the metal foil 61 including the first dark film 62 and the second dark film 63 is etched. By this etching, the metal foil 61 including the first dark film 62 and the second dark film 63 is patterned in substantially the same pattern as the resist pattern 65. As a result, the conductive metal layer 47, the first dark color layer 48, and the second dark color layer 49 which are to form the conductive thin line 50 are formed from the patterned metal foil 61. As the corrosive solution used for the etching process, known corrosive solutions can be appropriately selected and used according to the materials of the metal foil 61 and the dark films 62 and 63. For example, when the metal foil 61 is copper and the dark films 62 and 63 are copper (II) oxide (CuO), an aqueous ferric chloride solution can be used.

Here, as compared with the conductive metal layer 47 generally made of a metal material, the dark layers 48 and 49 made of an oxide or sulfide of the metal material are less likely to be corroded by etching. For this reason, sideward erosion due to side etching proceeds more in the conductive metal layer 47 than in the dark layers 48 and 49. Also in the conductive metal layer 47, sideward erosion by the side etching is more likely to occur in the area separated from the dark layers 48, 49 than in the area near the dark layers 48, 49. For this reason, the conductive pattern sheet 20 (narrow portion 55) is provided in the middle portion 51 along the normal direction of the conductive pattern sheet 20 (heat generating plate 10) by the selection of the etching solution and the adjustment of the etching time. The first wide portion 56 having a width larger than the narrow portion 55 is provided on the side (the glass plate 11 side) opposite to the base 30 of the narrow portion 55 along the normal direction of the heating plate 10) A second wide portion 57 having a width larger than the narrow portion 55 is provided on the base 30 side (the glass plate 12 side) of the narrow portion 55 along the normal direction of the conductive pattern sheet 20, ie, substantially A conductive thin wire 50 having an hourglass (hourglass) cross-sectional shape can be produced. Similarly, the minimum width W _{min of} the conductive thin wire 50 of the conductive thin wire 50, the maximum width W _amax of the first wide portion 56 of the conductive thin wire 50, and the conductive thin wire by the selection of the etching solution and the adjustment of the etching time. The maximum width W _bmax of the 50 second wide portions 57 and the cross-sectional area of the conductive thin wire 50 can be made as desired.

  Thereafter, the resist pattern 62 is removed to produce a conductive pattern sheet 20 shown in FIG.

  Finally, the glass plate 11, the bonding layer 13, the conductive pattern sheet 20, the bonding layer 14, and the glass plate 12 are stacked in this order and heated and pressed. In the example shown in FIG. 14, first, 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 and the conductive pattern sheet to which the bonding layer 13 is temporarily bonded so that the sides of the glass plates 11 and 12 to which the bonding layers 13 and 14 are temporarily bonded face the conductive pattern sheet 20, respectively. 20, the glass plate 12 to which the bonding layer 14 has been temporarily bonded is stacked in this order and heated and pressed. Thereby, the glass plate 11, the conductive pattern sheet 20, and the glass plate 12 are joined via the bonding layers 13 and 14, and the heat generating plate 10 shown in FIG. 3 is manufactured.

  The conductive pattern sheet 20 according to the present embodiment described above includes the base material 30 and the conductive pattern 40 provided on the base material 30 and including the conductive thin line 50. In a cross section orthogonal to the extending direction of the conductive thin wire 50, the middle portion 51 along the normal direction of the conductive pattern sheet 20 has a narrow portion 55, and along the normal direction of the conductive pattern sheet 20 A first wide portion 56 having a width larger than the narrow portion 55 is provided on the opposite side of the narrow portion 55 to the base material 30, and the narrow portion 55 is provided along the normal direction of the conductive pattern sheet 20. A second wide portion 57 having a width larger than the narrow portion 55 is provided on the base 30 side.

  Further, the heat generating plate 10 of the present embodiment described above is disposed between the pair of glass plates 11 and 12 and the pair of glass plates 11 and 12 and includes the conductive pattern 40 including the conductive thin line 50; A conductive thin line 50 is provided with bonding layers 13 and 14 disposed between the conductive pattern 40 and at least one of the pair of glass plates 11 and 12, and the conductive thin line 50 has a cross section orthogonal to the extending direction of the conductive thin line 50. In the middle portion 51 along the normal direction of the heat generating plate 10, the narrow portion 55 is provided, and one side of the pair of glass plates 11 and 12 of the narrow portion 55 along the normal direction of the heat generating plate 10. , The first wide portion 56 having a width larger than the narrow portion 55, and along the normal direction of the heat generating plate 10, on the other side of the pair of glass plates 11, 12 of the narrow portion 55, A second wide portion 57 having a width larger than the narrow portion 55 is provided.

  According to such a conductive pattern sheet 20 and the heat generating plate 10, it is possible to secure a cross-sectional area sufficient for obtaining appropriate conductivity while reducing the maximum width W of the conductive thin wire 50. As a result, it is possible to obtain appropriate conductivity of the conductive pattern 40 while effectively making the conductive pattern 40 invisible.

  Note that various modifications can be made to the embodiment described above. Hereinafter, modifications will be described with reference to the drawings as appropriate. In the following description and the drawings used in the following description, with respect to parts that can be configured in the same manner as the embodiment described above, the same reference numerals as those used for the corresponding parts in the above embodiment are used. Duplicate descriptions will be omitted.

  A modification of the method of manufacturing the heat-generating plate 10 will be described with reference to FIGS. FIG. 15 to FIG. 19 are cross-sectional views showing a modification of the method of manufacturing the heat-generating plate 10 in order.

  First, the conductive pattern sheet 20 is produced. The conductive pattern sheet 20 can be manufactured by the method described in the example of the method of manufacturing the heat generating plate 10 described above.

  Next, the glass plate 11, the bonding layer 13, and the conductive pattern sheet 20 are stacked in this order and heated and pressed. In the example shown in FIG. 15, first, the bonding layer 13 is temporarily bonded to the glass plate 11. Next, the side of the glass plate 11 to which the bonding layer 13 is temporarily bonded faces the conductive pattern sheet 20, and the glass plate 11 to which the bonding layer 13 is temporarily bonded is made conductive. It piles up from the side of pattern 40, and heats and pressurizes. Thereby, as shown in FIG. 16, the glass plate 11 and the conductive pattern sheet 20 are bonded (temporary bonding or main bonding) through the bonding layer 13.

  Next, as shown in FIG. 17, the base 30 of the conductive pattern sheet 20 is removed. For example, when the holding layer 31 is formed to include a peeling layer, the substrate 30 of the conductive pattern sheet 20 can be peeled from the conductive pattern 40 and the bonding layer 13 using the peeling layer.

  As the release layer, for example, an interface release type release layer, an interlayer release type release layer, an aggregation release type release layer, or the like can be used. As the interfacial peeling type peeling layer, a peeling layer having relatively low adhesion to the conductive pattern 40 and the bonding layer 13 as compared to adhesion to the base material 30 can be suitably used. As such a layer, a silicone resin layer, a fluorine resin layer, a polyolefin resin layer, etc. may be mentioned. Moreover, compared with the adhesiveness with the conductive pattern 40 and the joining layer 13, the adhesiveness with the base material 30 can also use a peeling layer relatively low. The delamination type peeling layer includes a film of a plurality of layers, and the peeling between the plurality of layers is relatively lower than the adhesion with the conductive pattern 40 and the bonding layer 13 or the substrate 30. Layers can be illustrated. As an aggregation peeling type peeling layer, the peeling layer which disperse | distributed the filler as a dispersed phase in the base resin as a continuous phase can be illustrated.

  When an interfacial release type release layer having a layer having relatively lower adhesion to the conductive pattern 40 and the bonding layer 13 as compared to the adhesion to the substrate 30 is used as the release layer, the release layer and the conductive layer are electrically conductive. A peeling phenomenon occurs between the conductivity pattern 40 and the bonding layer 13. In this case, the peeling layer can be prevented from remaining on the conductive pattern 40 and the bonding layer 13 side. That is, the substrate 30 is removed together with the release layer. When the substrate 30 and the release layer are removed in this manner, the bonding layer 13 is exposed in the opening area 43 of the conductive pattern 40.

  On the other hand, when an interfacial peeling type peeling layer having a relatively low adhesion to the base 30 as compared to the adhesion to the conductive pattern 40 and the bonding layer 13 is used as the peeling layer, peeling is performed. Peeling occurs between the layer and the substrate 30. An interlayer peeling type peeling film having a plurality of layers as a peeling layer and having relatively low adhesion between the plurality of layers as compared with the adhesion between the conductive pattern 40 and the bonding layer 13 and the substrate 30. When a layer is used, a peeling phenomenon occurs between the plurality of layers. In the case of using a cohesive peeling type peeling layer in which a filler as a dispersed phase is dispersed in a base resin as a continuous phase as a peeling layer, a peeling phenomenon due to cohesive failure in the peeling layer occurs.

  Finally, the glass plate 11, the bonding layer 13, the conductive pattern 40, the bonding layer 14, and the glass plate 12 are stacked in this order and heated and pressed. In the example shown in FIG. 18, first, the bonding layer 14 is temporarily bonded to the glass plate 12. Next, the glass plate 11, the conductive pattern 40, the bonding layer 13, and the bonding layer 14 are formed so that the side to which the bonding layer 14 of the glass plate 12 is temporarily bonded faces the conductive pattern 40 and the bonding layer 13. The bonded glass plates 12 are stacked in this order and heated and pressed. Thereby, the glass plate 11, the conductive pattern 40, and the glass plate 12 are bonded (mainly bonded) via the bonding layers 13 and 14, and the heat generating plate 10 shown in FIG. 19 is manufactured.

  According to the heat generating plate 10 shown in FIG. 19, the heat generating plate 10 can be configured not to include the base material 30. Thereby, the thickness of the heat-generating plate 10 whole can be made small. In addition, the number of interfaces in the heating plate 10 can be reduced. Therefore, it is possible to suppress the decrease in optical characteristics, that is, the decrease in visibility.

  Next, with reference to FIG. 20 and FIG. 21, another modified example of the method of manufacturing the heat generating plate 10 will be described. FIG. 20 and FIG. 21 are cross sectional views sequentially showing another modified example of the method of manufacturing the heat generating plate 10. As shown in FIG.

  First, the glass plate 11 and the conductive pattern sheet 20 are bonded (temporarily bonded) through the bonding layer 13 in the same steps as the modification of the method of manufacturing the heat generating plate 10 described above, and from here The substrate 30 is removed. That is, one obtained by laminating the glass plate 11, the conductive pattern 40, and the bonding layer 13 described with reference to FIG. 17 in the modification of the method of manufacturing the heating plate 10 described above is obtained.

  Next, as shown in FIG. 20, the glass plate 11, the bonding layer 13, the conductive pattern 40, and the glass plate 12 are stacked in this order and heated and pressed. Thereby, the glass plate 11 and the conductive pattern 40 are bonded (mainly bonded) via the bonding layer 13, and the glass plate 11 and the glass plate 12 are bonded (mainly bonded) via the bonding layer 13. . Then, the heating plate 10 shown in FIG. 21 is manufactured.

  According to the heat generating plate 10 shown in FIG. 21, the heat generating plate 10 can be configured not to include the base material 30 and the bonding layer 14. Thereby, the thickness of the entire heat generating plate 10 can be further reduced. In addition, the number of interfaces in the heating plate 10 can be further reduced. Therefore, it is possible to more effectively suppress the decrease in optical characteristics, that is, the decrease in visibility. In addition, since the conductive pattern 40 and the glass plate 12 are in contact with each other, the heating efficiency of the glass plate 12 by the conductive pattern 40 can be increased.

  In the embodiment described above, the plurality of connection elements 43 included in the conductive pattern 40 are in a linear shape (linear portion) when viewed from the normal direction of the plate surface of the heat generating plate 10, respectively. Alternatively, at least a part of the plurality of connection elements 43 may have a shape other than a straight line, for example, a curved line or a broken line when viewed from the normal direction of the plate surface of the heat generating plate 10. Specifically, it may have a shape such as an arc shape, a parabolic shape, a wavy shape, a zigzag shape, a combination of a curve and a straight line, or the like. In particular, connection elements 43 connecting between two branch points 41 as a straight line are less than 20% of the plurality of connection elements 43, ie, 80% or more of the plurality of connection elements 43. It is preferable that is have a shape other than a straight line (linear portion).

  According to the conductive pattern 40 including the connecting element 43 having a shape other than such a straight line (straight line portion), light incident on the side surface of the connecting element 43 having a curved shape, a broken line shape or the like is Diffusely reflect. Thereby, light (such as light of headlights of oncoming vehicles, sunlight, etc.) incident on a side surface of the connection element 43 from a certain direction is reflected on the side surface in a certain direction corresponding to the incident direction. Be suppressed. Therefore, it can be suppressed that the reflected light is viewed by an observer such as a driver and the conductive pattern 40 having the connection element 43 is viewed by the observer. As a result, it is possible to suppress the deterioration of the visibility of the observer through the window glass due to the visual recognition of the conductive pattern 40.

  Also, in the embodiment described above, the conductive pattern 40 is determined based on the Voronoi diagram, that is, a large number of open areas 42 are arranged in a shape and pitch that does not have repetitive regularity (periodic regularity). Although it has a pattern, the conductive pattern 40 is not limited to such a pattern, and the conductive pattern 40 is a pattern in which open areas of the same shape such as triangle, quadrangle, hexagon, etc. are regularly arranged, open areas of different shapes Various patterns may be used, such as a pattern in which are regularly arranged.

  The heat generating plate 10 may be used for a rear window, a side window or a sunroof of the car 1. In addition, transparent parts of windows or doors of vehicles such as railway vehicles, aircraft, ships, spacecraft, etc., other than cars, windows or doors of buildings, windows or doors of storage or storage facilities such as refrigerators, display boxes, cabinets, etc. You may use for a part.

  Furthermore, the heat-generating plate 10 can also be used in places other than vehicles, in particular, parts that partition indoors and outdoors, for example, transparent parts of windows or doors of buildings, stores, houses, etc.

  Although some modifications to the above-described embodiment have been described above, it is of course possible to apply a plurality of modifications in combination as appropriate.

Reference Signs List 1 automobile 5 front window 7 power supply 10 heat generation plate 11 glass plate 12 glass plate 13 bonding layer 14 bonding layer 15 wiring portion 16 connection portion 20 conductive pattern sheet 30 base 31 holding layer 40 conductive pattern 41 branch point 42 opening area 43 Connecting element 47 conductive metal layer 48 first dark layer 49 second dark layer 50 conductive fine wire 50 a first surface (tip surface)
50b second surface (base end surface)
50c side surface 50d side surface 51 middle portion 55 narrow portion 56 first wide portion 57 second wide portion 61 metal foil 62 first dark film 63 second dark film 65 resist pattern

Claims (11)

A heating plate that generates heat when a voltage is applied.
A first glass plate,
A second glass plate,
A conductive pattern disposed between the first glass plate and the second glass plate and including a conductive thin wire;
A first bonding layer disposed between the conductive pattern and the first glass plate and bonding the conductive pattern to the first glass plate;
And a second bonding layer disposed between the conductive pattern and the second glass plate and bonding the conductive pattern to the second glass plate.
The conductive thin line is
In a cross section orthogonal to the extending direction of the conductive thin line, a middle portion along the normal direction of the heat generating plate has a narrow portion,
It has a first wide portion having a larger width than the narrow portion on the first glass plate side of the narrow portion along the normal direction of the heat generating plate,
A heat generating plate having a second wide portion having a width larger than that of the narrow portion on the second glass plate side of the narrow portion along the normal direction of the heat generating plate. A heating plate that generates heat when a voltage is applied.
A first glass plate,
A second glass plate,
A conductive pattern disposed between the first glass plate and the second glass plate and including a conductive thin wire;
A bonding layer for bonding the conductive pattern and the first glass plate, and bonding the first glass plate and the second glass plate.
The conductive thin line is
In a cross section orthogonal to the extending direction of the conductive thin line, a middle portion along the normal direction of the heat generating plate has a narrow portion,
It has a first wide portion having a larger width than the narrow portion on the first glass plate side of the narrow portion along the normal direction of the heat generating plate,
A heat generating plate having a second wide portion having a width larger than that of the narrow portion on the second glass plate side of the narrow portion along the normal direction of the heat generating plate. The minimum width of the narrow portion of the conductive thin line is W _min (μm), the maximum width of the first wide portion is W _amax (μm), and the maximum width of the second wide portion is W _bmax ( The heat generating plate according to claim 1 or 2, which satisfies the following relationship (a) and (b) when .mu.m).
W _amax −W _min ≦ 10 (a)
W _bmax −W _min ≦ 10 (b) _Assuming that the maximum width of the first wide portion of the conductive thin line is W _amax (μm) and the maximum width of the second wide portion is W _bmax (μm), the following relationship (c) is obtained: The heat generating plate according to any one of claims 1 to 3, which satisfies the condition.
W _amax ≦ W _bmax (c) _Assuming that the maximum width of the first wide portion of the conductive thin line is W _amax (μm) and the maximum width of the second wide portion is W _bmax (μm), the following relationship (d) is obtained: The heat generating plate according to any one of claims 1 to 4, which satisfies the condition.
| W _amax −W _bmax | = 0 (d)   The heat generating plate according to any one of claims 1 to 5, wherein the conductive pattern is formed by patterning a conductive layer by etching. The conductive pattern has a pattern that defines a plurality of open areas,
The heat generating plate according to any one of claims 1 to 6, wherein the conductive pattern includes a plurality of connection elements extending between two branch points to define the opening area.   The heat generating plate according to any one of claims 1 to 7, wherein an average of the number of the connection elements extending from one branch point in the conductive pattern is greater than 3.0 and less than 4.0. The conductive pattern includes open areas respectively surrounded by four, five, six and seven connecting elements,
The heat generating plate according to any one of claims 1 to 8, wherein among the open areas included in the conductive pattern, the open area surrounded by six connection elements is the largest.   The heat generating plate according to any one of claims 1 to 9, wherein at least a part of the plurality of connection elements has a curved or broken line shape as viewed in the normal direction of the plate surface of the heat generating plate.   The vehicle provided with the heat generating plate as described in any one of Claims 1-10.

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