JP7033264B2 - Seats with conductors, heating plates and vehicles - Google Patents

Description

The present invention relates to a heat-generating plate having a conductive sheet having a heat-generating conductor, a heat-generating plate having a pair of substrates and a sheet with a conductor arranged between the pair of substrates, and a vehicle having the heat-generating plate.

Conventionally, a transparent heat generating plate having a heat generating conductor has been widely used. The heating plate is used, for example, in a defroster (defrosting device) used for a window glass of a vehicle. The heat-generating plate generates heat by resistance heating when the heat-generating conductors used therein are energized (see, for example, Patent Document 1, Patent Document 2, and Patent Document 3). The heat-generating plate applied to the window glass of a vehicle removes the fogging of the window glass by raising the temperature of the heat-generating conductor, melts the snow and ice adhering to the window glass, or removes water droplets adhering to the window glass. By evaporating it, the visibility of the occupants can be secured.

Japanese Unexamined Patent Publication No. 2013-173402 Japanese Unexamined Patent Publication No. 8-72674 Japanese Unexamined Patent Publication No. 2016-85889

In the field of view through the conventional transparent heating plate, there may be a problem that flicker is visually recognized. Flickering is a phenomenon in which bright and shining fine linear or dot-like light is visually recognized. As a result of diligent studies by the present inventors, it was found that flicker occurs when light such as sunlight is incident on the heat generating plate from the outside and the light is reflected by the heat generating conductor of the heat generating plate. In particular, the conductor constituting the conventional heat generating conductor as in Patent Document 3 has a rectangular or trapezoidal cross-sectional shape. In this case, as shown in FIG. 12, the light incident on the heating plate from the outside is reflected in the same direction. The light reflected in the same direction is visually recognized and flickers, for example, when the heating plate is used as the front window of the vehicle, it obstructs the view of the occupants of the vehicle, especially the driver. That is, the visibility deteriorates in the view through the heat generating plate.

The present invention has been made in consideration of such a point, and an object of the present invention is to make the reflection by the conductor constituting the heat generating conductor inconspicuous in the sheet with a conductor and to secure a good field of view. do.

The sheet with a conductor of the present invention is
A heat-generating conductor that generates heat when a voltage is applied,
A base film that supports the heat-generating conductor is provided.
The heat-generating conductor has a linear conductor and has a linear conductor.
The contour line of the linear conductor in the cross section orthogonal to the longitudinal direction of the linear conductor is the base film from the top farthest from the base film along the normal direction of the base film. Includes an outwardly convex curved portion between at least one bottom that is closest to the substrate film along the normal direction of.

In the sheet with a conductor of the present invention, the contour line may extend outward from the straight line connecting the top and the bottom.

In the sheet with a conductor of the present invention, the inclination angle of the tangent line at the portion having a convex curve toward the outside of the contour line with respect to the film surface of the base film is 45 ° or more. May include.

In the sheet with a conductor of the present invention, the length of the portion having a convex curve toward the outside of the contour line is other than the portion having a convex curve toward the outside of the contour line. It may be longer than the length of the portion.

In the sheet with a conductor of the present invention, the contour line may consist only of one or more outwardly convex curves between the top and the at least one bottom.

In the sheet with a conductor of the present invention, the curved portion of the contour line may be a curved portion having a radius of curvature of 2 μm or more and 20 μm or less.

In the sheet with a conductor of the present invention, the linear conductor may contain copper.

The heating plate of the present invention is
A pair of boards and
The above-mentioned sheet with a conductor is provided between the pair of substrates.

The vehicle of the present invention includes the heating plate described above.

According to the present invention, in a sheet with a conductor, the light reflected by the linear conductor constituting the heat generating conductor can be made inconspicuous, and a good field of view can be ensured.

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 equipped with a front window composed of a heating plate as an example of a vehicle. FIG. 2 is a view showing the heat generating plate from the normal direction of the plate surface. FIG. 3 is a cross-sectional view of the heating plate in lines III-III of FIG. FIG. 4 is a plan view showing a sheet with a conductor from the normal direction of the sheet surface, and is a plan view showing an example of a heat generating conductor. FIG. 5 is a cross-sectional photograph showing an example of a linear conductor according to an embodiment of the present invention. FIG. 6 is a cross-sectional photograph showing a conventional linear conductor. FIG. 7 is a diagram for explaining an example of a method for manufacturing a heat generating plate. FIG. 8 is a diagram for explaining an example of a method for manufacturing a heat generating plate. FIG. 9 is a diagram for explaining an example of a method for manufacturing a heat generating plate. FIG. 10 is a diagram for explaining the operation of the heat generating plate of FIG. FIG. 11 is a diagram for explaining the operation of the conventional heating plate. FIG. 12 is a diagram for explaining the operation of the conventional heating plate. FIG. 13 is a diagram for explaining the operation of the heat generating plate of FIG. FIG. 14 is a diagram for explaining the operation of the conventional heating plate. FIG. 15 is a diagram for explaining the operation of the conventional heating plate.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, the scale and the aspect ratios are appropriately changed and exaggerated from those of the actual product for the convenience of illustration and comprehension.

In addition, in this specification, the terms "board", "sheet", and "film" are not distinguished from each other based only on the difference in names. For example, "sheet with conductor" is a concept including members that can be called a plate or film, and therefore, "sheet with conductor" is "plate with conductor (board)" or "with conductor". It cannot be distinguished only by the difference in the name from the member called "film".

Further, the "sheet surface (plate surface, film surface)" is a target sheet-like member (plate-like) when the target sheet-like (plate-like, film-like) member is viewed as a whole and in a broad sense. A surface that coincides with the plane direction of a member (member, film-like member).

In addition, the terms such as "parallel", "orthogonal", and "identical" and the values of length and angle, etc., which specify the shape and geometric conditions and their degrees as used in the present specification, are strictly referred to. Without being bound by the meaning, we will interpret it including the range where similar functions can be expected.

1 to 15 are diagrams for explaining one embodiment according to the present invention. Of these, FIG. 1 is a diagram schematically showing an automobile provided with a heating plate, FIG. 2 is a view of the heating plate viewed from the normal direction of the plate surface, and FIG. 3 is a view of FIG. 2III. It is sectional drawing of the heating plate along the line III.

As shown in FIG. 1, an automobile 1 as an example of a vehicle has windowpanes such as a front window, a rear window, and a side window. Here, it is illustrated that the front window 5 is composed of a heating plate 10. Further, the automobile 1 has a power source 7 such as a battery.

FIG. 2 shows the heating plate 10 viewed from the normal direction of the plate surface. Further, FIG. 3 shows a cross-sectional view of the heating plate 10 of FIG. 2 corresponding to lines III-III. In the example shown in FIG. 3, the heating plate 10 is a pair of substrates 11 and 12, a sheet 20 with a conductor arranged between the pair of substrates 11 and 12, and the substrates 11 and 12 and a sheet with a conductor. It has bonding layers 13 and 14 for joining 20 and. In the examples shown in FIGS. 1 and 2, the heating plate 10 is curved, but in the other figures, the heating plate 10 and the substrates 11 and 12 are used for simplification of the illustration and facilitation of understanding. It is illustrated in a flat plate shape.

Further, as is well shown in FIG. 2, the heat generating plate 10 has a wiring portion 15 for energizing the heat generating conductor 30. In the illustrated example, the heating conductor 30 of the sheet 20 with a conductor is energized from the wiring portion 15 by a power source 7 such as a battery, and the heat generating conductor 30 is heated by resistance heating. The heat generated by the heat generating conductor 30 is transferred to the substrates 11 and 12, and the substrates 11 and 12 are heated. This makes it possible to remove fogging due to dew condensation adhering to the substrates 11 and 12. Further, when snow or ice is attached to the substrates 11 and 12, the snow or ice can be melted. Therefore, the visibility of the occupants is ensured well. Although not shown, a switch is usually inserted (connected in series) between the power supply 7 and the bus bar 25 connected to the heat generating conductor 30. Then, the switch is closed and the heating conductor 30 is energized only when the heating plate 10 needs to be heated.

Hereinafter, each component of the heat generating plate 10, that is, the substrates 11 and 12, the bonding layers 13 and 14, and the sheet 20 with a conductor will be described.

First, the substrates 11 and 12 will be described. When the substrates 11 and 12 are used for the front window of an automobile as in the example shown in FIG. 1, it is preferable to use the substrates 11 and 12 having a high visible light transmittance so as not to obstruct the view of the occupant. Examples of the materials of the substrates 11 and 12 include soda lime glass and blue plate glass. The visible light transmittance of the substrates 11 and 12 is preferably 90% or more. Here, the visible light transmittances of the substrates 11 and 12 were measured in the measurement wavelength range of 380 nm to 780 nm using a spectrophotometer (“UV-3100PC” manufactured by Shimadzu Corporation, JIS K 0115 compliant product). It is specified as the average value of the transmittance at each wavelength. The visible light transmittance of this part may be lowered by coloring a part or the whole of the substrates 11 and 12. In this case, it is possible to block the direct sunlight and make it difficult to see the inside of the vehicle from the outside of the vehicle.

Further, the substrates 11 and 12 preferably have a thickness of 1 mm or more and 5 mm or less. With such a thickness, the substrates 11 and 12 having excellent strength and optical characteristics can be obtained. The pair of substrates 11 and 12 may be made of the same material and configured in the same manner, or may be different from each other in at least one of the materials and the composition.

Next, the bonding layers 13 and 14 will be described. One bonding layer 13 is arranged between the one substrate 11 and the sheet 20 with a conductor, and the one substrate 11 and the sheet 20 with a conductor are bonded to each other. The other bonding layer 14 is arranged between the other substrate 12 and the sheet 20 with a conductor, and the other substrate 12 and the sheet 20 with a conductor are bonded to each other.

As such bonding layers 13 and 14, layers made of materials having various adhesiveness or adhesiveness can be used. Further, it is preferable to use the bonding layers 13 and 14 having a high visible light transmittance. As a typical bonding layer, a layer made of polyvinyl butyral (PVB) can be exemplified. The thicknesses of the bonding layers 13 and 14 are preferably 0.15 mm or more and 1 mm or less, respectively. The pair of bonding layers 13, 14 may be made of the same material and configured in the same manner, or may be different from each other in at least one of the materials and the composition.

The heat generating 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, the substrates 11 and 12 of the heat generating plate 10, the bonding layers 13 and 14, and the base film of the sheet 20 with a conductor described later will be described. At least one of 21 may be provided with some function. As an example, the functions that can be imparted to the heat generating plate 10 include an antireflection (AR) function, a scratch resistant hard coat (HC) function, an infrared shielding (reflection) function, an ultraviolet shielding (reflection) function, and antifouling. Functions and the like can be exemplified.

Next, the sheet 20 with a conductor will be described. The sheet 20 with a conductor generates heat provided on a base film 21, a primer layer 22 provided on one of the base films 21, a pair of bus bars 25, and a surface facing the primer layer 22. It has a conductor 30 for use. In the present embodiment, the sheet 20 with a conductor has substantially the same plane dimensions as the substrates 11 and 12, and is arranged over the entire heating plate 10, but the front portion of the driver's seat in the example of FIG. Etc., it may be arranged only in a part of the heat generating plate 10. Hereinafter, each component of the sheet 20 with a conductor will be described.

The base film 21 functions as a base material that supports the heat generating conductor 30. The base film 21 is a so-called transparent electrically insulating film that transmits a wavelength in the visible light wavelength band (380 nm to 780 nm). The base film 21 may be made of any material as long as it can transmit visible light and can appropriately support the heat generating conductor 30, and may be, for example, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polystyrene, or annular material. Polyolefin and the like can be mentioned. Further, the base film 21 preferably has a thickness of 0.03 mm or more and 0.20 mm or less in consideration of light transmission, appropriate supportability of the heat generating conductor 30, and the like.

In addition, "transparent" means having transparency to the extent that one side of the base film can be seen through the base film, for example, 30. It means that it has a visible light transmittance of% or more, more preferably 70% or more. The visible light transmittance is the average transmittance at each wavelength when measured using a spectrophotometer (“UV-3100PC” manufactured by Shimadzu Corporation, JIS K0115 compliant product) within the measurement wavelength range of 380 nm to 780 nm. Specified as a value.

The primer layer 22 is a layer for improving the adhesion of the heat generating conductor 30 described later on the base film 21. That is, it is desirable that the primer layer 22 has high adhesiveness to both the base film 21 and the heat generating conductor 30. Further, the primer layer 22 is transparent like the base film 21. Examples of the material of the primer layer 22 include thermoplastic resins such as acrylic resin, polyester resin, and polyolefin resin, and ionized radiation curable resins such as radical polymerizable monomer, radical polymerizable prepolymer, and cationically polymerizable prepolymer. ..

The bus bar 25 is electrically connected to the corresponding wiring portion 15. The voltage of the power supply 7 connected to the wiring portion 15 is applied between the pair of bus bars 25.

Next, the heat generating conductor 30 will be described with reference to FIG. FIG. 4 is a plan view of the sheet 20 with a conductor as viewed from the normal direction of the sheet surface.

The heat generating conductors 30 are arranged between the pair of bus bars 25, and are electrically connected to each other so as to connect the pair of bus bars 25. The heat generating conductor 30 is formed of linear conductors 31 arranged in a predetermined pattern. When a voltage is applied to the heat generating conductor 30 via the wiring portion 15 and the bus bar 25, the heat generating conductor 30 generates heat due to resistance heating. Then, this heat is transferred to the substrates 11 and 12 via the bonding layers 13 and 14, so that the substrates 11 and 12 are warmed.

The heat generating conductor 30 can be arranged in various patterns. As an example, in the example shown in FIG. 4, the heat generating conductor 30 is formed by arranging the linear conductor 31 in a mesh-like pattern defining a large number of openings 33. The heat generating conductor 30 includes a plurality of connecting elements 34 extending between the two branch points 32 to define the opening 33. That is, the linear conductor 31 of the heat generating conductor 30 is configured as a collection of a plurality of connecting elements 34 forming branch points 32 at both ends.

Alternatively, as another example, the heat generating conductor 30 may be formed by being arranged in a striped pattern having a plurality of linear conductors 31 connecting the pair of bus bars 25. More specifically, a plurality of linear conductors 31 extend from one bus bar 25 to the other bus bar 25, and from each other in a direction non-parallel to the extending direction of the linear conductor 31. They may be arranged apart from each other.

Materials for forming such a heat-generating conductor 30 (linear conductor 31) and bus bar 25 include, for example, gold, silver, copper, platinum, aluminum, chromium, molybdenum, nickel, titanium, palladium, and indium. , A metal such as tungsten, and one or more alloys containing one or more of these metals can be exemplified. In particular, it is preferable to contain copper, which is inexpensive and has good electrical conductivity. The heat-generating conductor 30 and the bus bar 25 may be formed of the same material, or may be formed of different materials.

In the example shown in FIG. 3, the linear conductor 31 has a semi-elliptical cross section as a whole. The width W of the linear conductor 31, that is, the length of the linear conductor 31 along the plate surface of the heating plate 10 (in the illustrated example, the linear conductor 31 along the plate surface of the heating plate 10). The length of the bottom portion 31a2) is preferably 2 μm or more and 20 μm or less. Further, the height (thickness) H, that is, the length from the top portion 31a1 to the bottom portion 31a2 of the linear conductor 31 along the normal direction to the plate surface of the heating plate 10 shall be 1 μm or more and 60 μm or less. Is preferable. According to the linear conductor 31 having such dimensions, since the linear conductor 31 is sufficiently thinned, the heat generating conductor 30 can be effectively invisible.

Further, the heat generating conductor 30 can be formed by using an opaque metal material as described above. On the other hand, the ratio of the region on the base film 21 not covered by the heat generating conductor 30, that is, the aperture ratio is as high as 70% or more and 99% or less. Further, the line width of the linear conductor 31 is about 2 μm or more and 20 μm or less. Therefore, the region where the heat generating conductor 30 is provided is transparently grasped as a whole, and the presence of the heat generating conductor 30 does not impair the transparency of the heat generating plate 10.

As described above, from the viewpoint of ensuring the transparency of the heat generating plate 10 or the visibility through the heat generating plate 10, the linear conductor 31 of the heat generating conductor 30 is a base material so as to increase the aperture ratio. It is formed on the film 21. As a result, as shown in FIG. 3, the bonding layer 13 and the base film 21 of the sheet 20 with the conductor form a region between the opening 33 of the linear conductor 31, that is, the adjacent linear conductors 31. Are in contact through. That is, the heat generating conductor 30 is embedded in the bonding layer 13.

Here, the contour line 31a of the linear conductor 31 in a cross section orthogonal to the longitudinal direction of the linear conductor 31 will be described. As shown in FIG. 3, the contour line 31a of the linear conductor 31 has an elliptical arc shape. That is, a portion having a convex curve toward the outside is included between the top portion 31a1 of the linear conductor 31 and at least one bottom portion 31a2. The top portion 31a1 of the linear conductor 31 means a portion farthest from the base film 21 along the normal direction of the base film 21. Further, the bottom portion 31a2 of the linear conductor 31 means a portion closest to the base film 21 along the normal direction of the base film 21. Further, an outwardly convex curve does not simply mean that it protrudes outward, but that it is mathematically convex. That is, an outwardly convex curve is a linear conductor 31 in which a straight line connecting arbitrary two points in the curve is separated from the curve between the two points. It means that it is located inside, in other words, any part of the curve is located between both ends of the part and outside the straight line connecting both ends of the part.

FIG. 5 is a photograph of a cross section of the linear conductor 31 according to the embodiment of the present invention. As is clear from FIG. 5, the contour line 31a of the linear conductor 31 includes an outwardly convex curved portion between the top portion 31a1 and the bottom portion 31a2 on at least one side. There is. In FIG. 5, the surface of the linear conductor 31 is plated with, for example, copper to form a plating layer 35. In this case, the contour line 31a of the linear conductor 31 means the contour line of the plating layer 35. On the other hand, the conventional linear conductor 131 is formed so that the cross-sectional shape is rectangular or trapezoidal. That is, the contour line 131a is formed so as to be composed of only straight lines. Alternatively, in the conventional linear conductor 31 manufactured by etching, as is clear from the cross-sectional photograph of FIG. 6, the contour line 131a of the linear conductor 131 is inward due to the etching in the manufacturing process. It is formed as a concave curve that is recessed.

Further, the contour line 31a of the linear conductor 31 shown in FIG. 5 is formed by an outwardly convex curve as a whole. Therefore, the contour line 31a of the linear conductor 31 shown in FIG. 5 extends outward from the straight line connecting the top portion 31a1 and the bottom portion 31a2. That is, the contour line 31a projects outward between the top portion 31a1 and the bottom portion 31a2.

It should be noted that the outwardly convex curve included in the contour line 31a can exert a useful effect such as making flicker inconspicuous, as will be described later. From the viewpoint of sufficiently ensuring this effect, it is effective that the portion of the contour line 31a that becomes a convex curve toward the outside is configured as follows. First, it is preferable to include a portion where the inclination angle of the tangent line in the portion of the contour line 31a having a convex curve toward the outside with respect to the film surface of the base film 21 is 45 ° or more. Further, the length of the portion of the contour line 31a that is convex toward the outside is the length of the other portion, that is, the length of the portion that is convex toward the outside of the contour line 31a. It is preferably longer than the length of the portion other than the portion. Further, between the top portion 31a1 and at least one bottom portion 31a2, the contour line 31a ideally consists of only a portion that is curved outward. In this case, the portion having a convex curve toward the outside may be one or a plurality. Further, it is preferable that the curved portion of the contour line 31a has a radius of curvature of 2 μm or more and 20 μm or less.

Here, a method of specifying the cross-sectional shape of the linear conductor 31 and a method of measuring the dimensions will be described. As for the cross-sectional shape of the linear conductor 31, the cross-sectional shape of the linear conductor 31 may be observed with a microscope, and the shape and dimensions may be measured based on the microscopic observation image. As the microscope, for example, a scanning electron microscope can be used. The cross section of the linear conductor 31 can be obtained by, for example, processing using a microtome or focused ion beam (FIB) processing.

The photograph of the cross section of the linear conductor 31 in FIG. 5 is an image of the cross section obtained by processing using a microtome. As a specific procedure, first, the sheet 20 with a conductor is cut out to a size of 5 mm × 10 mm with a trimming razor, and then embedded in a resin. Next, a trimming razor is used to expose the cross section of the sheet 20 with a conductor. The resulting cross section is then trimmed using an ultramicrotome. In this trimming, in order to reduce the mechanical distortion of the cross-sectional shape, the material is cut with a microtome about 1 mm in the direction perpendicular to the cross-sectional direction together with the embedded resin. At this time, cutting is performed while adjusting the angle so that a cross section perpendicular to the extending direction of the linear conductor 31 can be obtained, and a desired cut surface is obtained.

On the other hand, the photograph of the cross section of the linear conductor 131 in FIG. 6 is an image of the cross section obtained by the focused ion beam (FIB) processing. Specifically, a sheet with a conductor is cut out by a trimming razor to have a thickness of 5 mm × 10 mm, and then fixed to a sample table using Ag paste. Then, in order to obtain continuity between the cut-out sheet with a conductor and the sample table, carbon vapor deposition is performed, and further Pt sputtering is performed, and then the sheet is introduced into an apparatus for FIB processing. In the apparatus for performing FIB processing, etching processing is performed with a Ga ion beam in order to obtain a predetermined cross section. However, since the Ga ion beam is slightly scattered around the part to be processed, the etching process is performed after forming a tungsten depot film in order to prevent the surface around the part to be processed from being etched. conduct. Next, by focused ion beam (FIB) processing, the cross section of the linear conductor 131 perpendicular to the extending direction of the linear conductor 131 in the sheet with the conductor is exposed. For FIB processing, a processing device FB-2100 manufactured by Hitachi High-Technology Co., Ltd. was used. As the processing conditions, the extraction voltage was 8.2 kV, the emission current was 3.2 μA, and the acceleration voltage was 40 kV. It also has a condenser lens and has an aperture of 150. The final finishing width was 20 μm.

The cross sections of the exposed linear conductor 31 and the linear conductor 131 were observed and imaged as images by a scanning electron microscope (SEM). As the SEM, S-4800 TYPE2 manufactured by Hitachi High-Technology Co., Ltd. was used. As observation conditions, the acceleration voltage was 3.0 kV, the emission current was 10 μA, and the working distance was 15 mm. Further, the detector was set to Mix, which is a mode for obtaining information on both the upper detector and the lower detector. In the case of processing using a microtome, the cross section can be observed from the front. Therefore, the shape and dimensions of the cross section can be specified based on the photograph taken from the front direction. On the other hand, in the case of FIB processing, the cross section cannot be observed from the front due to its characteristics, and the observation is performed from an inclined direction. Therefore, the shape of the linear conductor 31 in the photograph taken is compressed in the vertical direction from the actual cross-sectional shape. Therefore, when measuring the dimensions from this photograph, it is necessary to stretch the image in the vertical direction at a ratio according to the shooting direction. For example, in the case of the obtained cross-sectional photograph, an image taken from a direction inclined by 45 ° in the upward direction (direction toward the side where the heat-generating conductor 30 is provided) of the sheet 20 with a conductor from the front direction of the cross-section. It is necessary to specify the shape and dimensions of the cross section, assuming that the actual cross-sectional shape is an image stretched √2 times in the vertical direction. In the cross-sectional image shown in FIG. 6, the dimensions excluding the above-mentioned film formation are measured. Further, in FIGS. 5 and 6, the observation of the cross section is performed at a magnification of 5000 to 8000 times.

Next, an example of a method for manufacturing the heat generating conductor 30 and the heat generating plate 10 will be described with reference to FIGS. 7 to 9. 7 to 9 are cross-sectional views showing an example of a method for manufacturing the heating plate 10 in order.

First, the primer layer 22 is provided on the base film 21. The primer layer 22 is formed by applying the resin composition forming the primer layer to the base film 21. Alternatively, when the primer layer 22 is a film of a thermoplastic resin composition that is solid at room temperature, the primer layer 22 may be provided by being laminated on the base film 21.

Further, the composition of the above-mentioned conductor forming the linear conductor 31 is injected into the mold plate 60 in which the concave portions 61 having a mesh-like or striped pattern are formed. The pattern of the recess 61 is a pattern corresponding to the arrangement pattern of the heat generating conductor 30. Further, the mold 61a of the recess 61 has a shape corresponding to the linear conductor 31. That is, in the cross section shown in FIG. 7, the contour line defining the concave portion 61 of the mold 61a includes a curve convex toward the inside of the concave portion 61 (curve convex toward the mold plate 60). Therefore, the contour line 31a of the linear conductor 31 manufactured by the plate 60 includes the above-mentioned outwardly convex curve in its cross section.

Then, as shown in FIG. 7, the primer layer 22 is brought into close contact with the mold plate 60. The primer layer 22 adheres to the heat generating conductor 30 due to its adhesiveness. That is, the base film 21 holds the heat generating conductor 30 via the primer layer 22. Then, the primer layer 22 is cured by a curing means corresponding to the resin composition of the primer layer 22, and the template 60 is removed to produce the sheet 20 with a conductor shown in FIG.

Although not shown, the linear conductor 31 may be plated to provide the plating layer 35. Examples of the metal to be plated include copper, silver, gold, nickel and the like, but inexpensive and highly conductive copper is preferable. The contour line 31a of the linear conductor 31 changes due to the plating, but since the plating is performed uniformly, the radius of curvature becomes large, but the curve remains convex outward.

Finally, as shown in FIG. 9, the bonding layer 13 and the substrate 11 are laminated from the side of the heat-generating conductor 30 of the conductor-attached sheet 20, and the conductor-attached sheet 20 and the substrate 11 are formed by, for example, heating and pressurizing. To join. Similarly, the bonding layer 14 and the substrate 12 are laminated from the side of the base film 21, and the sheet 20 with the conductor and the substrate 12 are bonded. As a result, the heat generating plate 10 shown in FIG. 3 is manufactured.

Next, with reference to FIGS. 10 to 15, while comparing the action of the heat-generating conductor 30 on the heat-generating plate 10 of the embodiment of the present invention with the action of the heat-generating conductor 130 on the conventional heat-generating plate 110. explain. In FIGS. 10 to 15, the configuration of the heating plate is appropriately omitted or exaggerated.

The heating plate can be applied to and used in the front window 5 of the automobile 1 as shown in FIG. Therefore, FIGS. 10 to 15 show an embodiment in which the heating plate is used with the normal direction of the heating plate tilted from the vertical direction. In FIGS. 10 to 12, the heat-generating conductor on the base film is arranged on the inner side of the automobile. On the other hand, in FIGS. 13 to 15, the heat generating conductor on the base film is arranged on the outer side of the automobile.

In the conventional heating plate 110 shown in FIGS. 11, 12, 14 and 15, the light L11, L12, L14, L15 from the outside such as sunlight is on the surface of the linear conductor 131, that is, the contour line 131a. Be reflected. In the linear conductor 131 having an inwardly recessed concave contour line 131a as shown in FIG. 6, when the heat generating conductor 130 on the base film is arranged on the inner side of the automobile, As shown in FIG. 11, the light L11 from the outside is collected (condensed) at a certain position by being reflected by the linear conductor 131. Further, even when the heat generating conductor 130 on the base film is arranged on the outer side of the automobile, as shown in FIG. 14, the light L14 from the outside is reflected by the linear conductor 131. , Will be collected at a certain position (condensed). Even in the case of the linear conductor 131 in which the contour line 131a is a straight line, when the heat generating conductor 130 on the base film is arranged on the inner side of the automobile, as shown in FIG. 12, the light L12 from the outside is emitted. When the heat-generating conductor 130 on the substrate film is reflected in the same direction by the linear conductor 131 and is arranged on the outer side of the automobile, as shown in FIG. 15, the light L15 from the outside is a line. It is reflected in the same direction by the shape conductor 131. Therefore, in any case, the reflected light of the light from the outside can be strongly observed in the field of view through the heat generating plate 110. That is, due to the light from the outside, flicker is visually recognized in the field of view through the heat generating plate 110, and the visibility is deteriorated.

On the other hand, in the heat generating plate 10 of the present embodiment shown in FIGS. 10 and 13, the light L10 and L13 from the outside have a convex curve toward the surface of the linear conductor 31, that is, outward. It is reflected by the contour line 31a including the portion. When the heat generating conductor 30 on the base film is arranged on the inner side of the automobile, as shown in FIG. 10, the light L10 from the outside is the outer side of the contour line 31a of the linear conductor 31. When it is reflected at the part that is curved toward, it is diffused without being collected at any position. Further, when the heat generating conductor 30 on the base film is arranged on the outer side of the automobile, as shown in FIG. 13, the light L13 from the outside is among the contour lines 31a of the linear conductor 31. When it is reflected at the part that is convex toward the outside, it is diffused without being collected at any position. In either case, the reflected light is diffused in the field of view through the heat generating plate 10, so that it is difficult to observe. As a result, flicker is not visually recognized in the view through the heat generating plate 10, and the visibility can be kept good. In particular, when the contour line 31a is located between the top portion 31a1 and the bottom portion 31a2 outside the straight line connecting the top portion 31a1 and the bottom portion 31a2, it is reflected at an arbitrary position of the linear conductor 31. It is possible to make it difficult for the reflected light to be visually recognized. This makes it possible to make the flicker less noticeable more effectively.

Further, as is clear from FIGS. 10 and 13, the above-mentioned effect of diffusing the reflected light is mainly exerted on the portion of the linear conductor 31 that corresponds to the side of the light source side. Therefore, since the portion of the contour line 31a having a convex curve toward the outside is provided in the portion corresponding to the side, the effect of diffusing the reflected light and not causing flicker is more effectively achieved. be able to. Specifically, by including the portion where the inclination angle of the tangent line in the portion of the contour line 31a that is convex toward the outside with respect to the film surface of the base film 21 is 45 ° or more. , The above-mentioned effect can be obtained at the portion corresponding to the side of the linear conductor 31. Further, when the inclination angle of the tangent line in the portion of the contour line 31a that is convex toward the outside with respect to the film surface of the base film 21 is only less than 45 °, the cross-sectional area of the linear conductor 31 Is significantly reduced, so that the resistance of the linear conductor 31 becomes too large, and there is a possibility that appropriate heat generation cannot be performed.

Further, from the viewpoint of diffusing the reflected light and making the flicker invisible, even if the contour line 31a has a part other than the portion having a convex curve toward the outside, it is outside the contour line 31a. It is preferable that the length of the portion having a convex curve toward the outside is longer than the length of the other portion, that is, the length of the portion other than the portion having a convex curve toward the outside of the contour line 31a. .. Furthermore, the contour line 31a has no portion other than a portion that is curved outward, that is, between the top portion 31a1 and at least one bottom portion 31a2, the contour line 31a is one or more. It is more preferable that it consists only of a portion having a convex curve toward the outside.

Further, when the radius of curvature of the contour line 31a is 2 μm or more and 20 μm or less as in the present embodiment, the radius of curvature is sufficiently small, so that light from the outside can be reliably diffusely reflected.

It should be noted that the above-mentioned action can be naturally performed even if the normal direction of the heating plate is not tilted from the vertical direction.

As described above, the conductor-equipped sheet 20 of the present embodiment includes the heat-generating conductor 30 that generates heat when a voltage is applied, and the base film 21 that supports the heat-generating conductor 30. The heat-generating conductor 30 has a linear conductor 31, and the contour line 31a of the linear conductor in a cross section orthogonal to the longitudinal direction of the linear conductor 31 is in the normal direction of the base film 21. Outwardly convex from the top 31a1 closest along the substrate film 21 to at least one bottom 31a2 closest to the substrate film 21 along the normal direction of the substrate film 21. Includes curved parts. According to such a sheet 20 with a conductor, light from the outside can be reflected and diffused at a portion of the linear conductor 31 having an outwardly convex curve. Therefore, even if the light incident from the outside is reflected by the heat generating conductor 30 of the sheet 20 with a conductor, the reflected light is bright and difficult to be observed, and the flicker can be made inconspicuous. That is, the light reflected by the linear conductor 31 constituting the heat-generating conductor 30 is made inconspicuous, and the visibility of the occupants of the vehicle, especially the driver, through the seat 20 with the conductor is ensured well. Can be done.

Further, in the sheet 20 with a conductor of the present embodiment, the contour line 31a extends outward from the straight line connecting the top portion 31a1 and the bottom portion 31a2. According to such a sheet with a conductor 20, in the cross section of the linear conductor 31, it is possible to exert the effect of diffusing the reflected light as a whole of the linear conductor 31 to prevent flicker. Therefore, it is possible to better secure the visibility of the occupant of the vehicle or the like, particularly the driver, through the seat 20 with the conductor.

Further, in the sheet 20 with a conductor of the present embodiment, the inclination angle of the tangent line at the portion of the contour line 31a having a convex curve toward the outside with respect to the film surface of the base film 21 is 45 ° or more. Including the part that is. According to such a sheet with a conductor 20, it is possible to obtain the effect of diffusing the reflected light and preventing flicker at the portion corresponding to the side of the linear conductor 31. Therefore, it is possible to better secure the visibility of the occupant of the vehicle or the like, particularly the driver, through the seat 20 with the conductor.

Further, in the sheet 20 with a conductor of the present embodiment, the length of the portion having a convex curve toward the outside of the contour line 31a becomes a convex curve toward the outside of the contour line 31a. It is longer than the length of the part other than the part where it is. According to such a sheet 20 with a conductor, the effect of diffusing the reflected light can be more strongly exerted than the action of condensing the light. Therefore, it is possible to better secure the visibility of the occupant of the vehicle or the like, particularly the driver, through the seat 20 with the conductor.

Further, in the sheet 20 with a conductor of the present embodiment, the contour line 31a consists of only one or more outwardly convex curves between the top portion 31a1 and at least one bottom portion 31a2. According to such a sheet 20 with a conductor, the effect of diffusing the reflected light can be exerted in the entire range of the contour line 31a of the linear conductor 31. Therefore, it is possible to better secure the visibility of the occupant of the vehicle or the like, particularly the driver, through the seat 20 with the conductor.

Further, in the sheet 20 with a conductor of the present embodiment, the curved portion of the contour line 31a is a curve having a radius of curvature of 2 μm or more and 20 μm or less. With such a heat-generating conductor 30, it is possible to reliably achieve the above-mentioned effect of diffuse-reflecting light from the outside.

It is possible to make various changes to the above-described embodiment.

In the above-described embodiment, the heating plate 10 includes the conductor-attached sheet 20 having the base film 21, but the heat generating plate 10 is formed by peeling off the base film 21 in the manufacturing process. The base film 21 may not be contained therein. In this case, the entire heat generating plate 10 can be made thinner and lighter. Further, the heat generated from the heat generating conductor 30 can be quickly transferred to the entire heat generating plate 10.

In the above-described embodiment, an example in which the heat generating plate 10 is formed in a curved surface is shown, but the present invention is not limited to this example, and the heat generating plate 10 may be formed in a flat plate shape.

The heating plate 10 may be used for the rear window, the side window, or the sunroof of the automobile 1. Further, it may be used for a transparent portion of a window or a door of a vehicle such as a railroad vehicle, an aircraft, a ship, or a spacecraft other than an automobile.

Further, the heating plate 10 is used not only for vehicles but also for places that separate indoors and outdoors, such as buildings, stores, transparent parts of windows or doors of houses, windows or doors of buildings, refrigerators, display boxes, cupboards, and the like. It can also be used for the transparent part of windows or doors of storage or storage equipment.

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

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

As an example, as shown in FIGS. 10 and 13, a portion where the contour line of the linear conductor 31 is a convex curve toward the outside in a cross section orthogonal to the longitudinal direction of the linear conductor 31. A heat generating plate 10 including a sheet 20 with a conductor including the above was prepared. In each aspect of FIGS. 10 and 13, the maximum inclination angles of the tangent to the film surface of the base film 21 at the portion having a convex curve toward the outside of the contour line are set to 60 °, 45 °, and 30 respectively. We prepared an example with °.

In each embodiment, in order to specify the maximum inclination angle of the tangent base film 21 with respect to the film surface in the portion of the linear conductor 31 having a convex curve toward the outside in the cross section. The substrates 11 and 12 and the bonding layers 13 and 14 were peeled off from the heat generating plate 10, and the sheet 20 with a conductor was processed using the above-mentioned microtome or FIB processing to expose the cross section. Then, the cross section was observed as an image by SEM and imaged. From the captured image, the maximum inclination angle of the tangent line in the portion having a convex curve toward the outside of the contour line was identified.

As a comparative example, as shown in FIGS. 11 and 14, the contour line of the linear conductor 131 is recessed inward with respect to the base film 21 in a cross section orthogonal to the longitudinal direction of the linear conductor 131. A heating plate 10 including a sheet 20 with a conductor having a curved shape, and a heating plate 10 having a sheet 20 with a conductor whose contour line of the linear conductor 131 is straight as shown in FIGS. 12 and 15. I prepared.

As described above, in the embodiment of FIGS. 10 to 12, when the heat generating plate 10 is applied to the front window 5 of the automobile 1, the heat generating conductor 30 on the base film 21 is arranged inside the automobile. In the embodiment shown in FIGS. 13 to 15, when the heat generating plate 10 is applied to the front window 5 of the automobile 1, the heat generating conductor 30 on the base film 21 is attached to the outside of the automobile. It is a mode assuming that it is arranged.

For the above-mentioned Examples and Comparative Examples, the flicker when observing the heat generating plate 10 was evaluated. The evaluation results are shown in Table 1 below. For the evaluation of flicker, when the heat generating plate 10 is visually observed, A is attached to the case where the flicker is not confirmed even if it is carefully observed, and when the flicker is observed carefully, the flicker is confirmed, but the visibility is obstructed. B was given to the cases that did not become, and C was given to the cases where the flicker was clearly observed and the visibility was obstructed.

As can be understood from the results of the flicker evaluation in Table 1, the flicker is clearly observed in the heating plate 10 provided with the conductor-equipped sheet 20 in the embodiments of FIGS. 11, 12, 14, and 15, and the flicker is clearly observed to obstruct the view. On the other hand, in the heat generating plate 10 provided with the conductor-equipped sheet 20 according to the embodiments shown in FIGS. 10 and 13, the flicker did not obstruct the view. That is, it is possible to secure a good view through the heat generating plate 10. In particular, when the maximum inclination angle of the tangent line in the convex curved portion is 45 ° or more, it is understood that flicker is not confirmed and the field of view through the heating plate 10 can be secured extremely well. Will be done.

1 Automobile 5 Front window 7 Power supply 10 Heat-generating plate 11 Substrate 12 Board 13 Bonding layer 14 Bonding layer 15 Wiring part 20 Sheet with conductor 21 Base film 22 Primer layer 25 Bus bar 30 Heat-generating conductor 31 Linear conductor 31a Contour line 32 Branch point 33 Opening 34 Connection element 35 Plating layer

Claims (9)

A heat-generating conductor that generates heat when a voltage is applied,
A base film that supports the heat-generating conductor is provided.
The heat-generating conductor has a linear conductor and has a linear conductor.
The surface of the linear conductor is plated with copper and is plated with copper.
The contour line of the linear conductor in the cross section orthogonal to the longitudinal direction of the linear conductor is the base film from the top farthest from the base film along the normal direction of the base film. Includes an outwardly convex curved portion between at least one bottom that is closest to the substrate film along the normal direction of.
The aperture ratio, which is the ratio of the region on the base film not covered by the heat generating conductor, is 70% or more and 99% or less.
A sheet with a conductor having a line width of 2 μm or more and 20 μm or less . The sheet with a conductor according to claim 1, wherein the contour line extends outward from a straight line connecting the top and the bottom. 2. The described sheet with a conductor. Claim 1 that the length of the portion having a convex curve toward the outside of the contour line is longer than the length of the portion other than the portion having a convex curve toward the outside of the contour line. The sheet with a conductor according to any one of 3 to 3. The sheet with a conductor according to any one of claims 1 to 3, wherein the contour line comprises only one or more outwardly convex curves between the top and the at least one bottom. .. The sheet with a conductor according to any one of claims 1 to 5, wherein the curved portion of the contour line is a curve having a radius of curvature of 2 μm or more and 20 μm or less. The sheet with a conductor according to any one of claims 1 to 6, wherein the linear conductor contains copper. A pair of boards and
A heat generating plate comprising the sheet with a conductor according to any one of claims 1 to 7 between the pair of substrates. A vehicle comprising the heating plate according to claim 8.

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