JP2019135723A - Heating plate, conductive pattern sheet and intermediate member - Google Patents

Abstract

To improve the degree of freedom of the pattern design of a conductive pattern forming a heating wire, and prevent the occurrence of the disconnection or the like when used in a curved heating plate.SOLUTION: A heating plate 10 includes: a pair of glass plates 11, 12; a conductive pattern sheet 20 which is arranged between the pair of glass plates 11, 12; and bonding layers 13, 14, 19 which are arranged between each glass plate 11, 12 and the conductive pattern sheet 20 and bonds the glass plates 11, 12 and the conductive pattern sheet 20. The conductive pattern sheet 20 includes: a sheet-like base material 30; and a conductive pattern 40 provided on the base material 30. The conductive pattern 40 includes a conductive thin line 41 formed of a conductive paste 50.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a heat generating plate having a conductive pattern sheet, a conductive pattern sheet, and an intermediate member having a conductive pattern sheet.

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

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

  In a conventional defroster device, a bonding layer and a heating wire are sandwiched between a pair of glass plates and heat-pressed to form a heating plate. For example, a heating wire made of a tungsten wire or the like manufactured in a separate process is disposed on one glass plate, and the one glass plate and the other glass plate are bonded to each other through a bonding layer, and are thermocompression bonded. However, in the method of arranging heating wires manufactured in a separate process, the arrangement pattern of heating wires is limited to simple shapes such as straight lines and wavy lines, and it is difficult to arrange them in a complicated shape.

  Moreover, many window glasses, such as a front window and a rear window of a vehicle, are curved in order to reduce air resistance and improve design. When a defroster device having a heating wire is provided on the curved window glass, it is necessary to sandwich the heating wire between a pair of curved glass plates to form a heating plate. In this case, the heating wire is also bent along the curved shape of the pair of glass plates. When the heating wire formed in the planar pattern is to be bent, the heating wire is partially stretched, and a large stress is generated at that portion. As a result, the heated heating wire is cracked or disconnected, and as a result, the defroster device may cause problems such as being unable to completely remove the fog.

  The present invention has been made in consideration of the above points, and an object thereof is to improve the degree of freedom in pattern design of a conductive pattern forming a heating wire. Moreover, it aims at preventing generation | occurrence | production of the disconnection etc. at the time of using for the curved heat generating plate.

The heating plate according to the present invention is:
A pair of glass plates;
A conductive pattern sheet disposed between the pair of glass plates;
A bonding layer disposed between each glass plate and the conductive pattern sheet and bonding the glass plate and the conductive pattern sheet; and
The conductive pattern sheet has a sheet-like base material and a conductive pattern provided on the base material,
The conductive pattern includes a conductive fine wire made of a conductive paste.

  In the heat generating plate according to the present invention, in the cross section orthogonal to the longitudinal direction of the conductive thin wire, the width of the conductive thin wire is from the base end portion connected to the base material to the distal end portion farthest from the base material. , It may become thinner gradually.

The conductive pattern sheet according to the present invention is:
A sheet-like substrate;
A conductive pattern provided on the substrate,
The conductive pattern includes a conductive fine wire made of a conductive paste.

The intermediate member according to the present invention is
The conductive pattern sheet described above;
A planarization layer provided on the conductive pattern sheet;
And a thermoplastic resin sheet layer laminated on the conductive pattern sheet from the side on which the flattening layer is provided.

  In the intermediate member according to the present invention, the planarizing layer may at least partially fill a region between two adjacent conductive thin wires forming the conductive pattern.

  ADVANTAGE OF THE INVENTION According to this invention, the freedom degree of the pattern design of the electroconductive pattern which makes a heating wire can be improved. Furthermore, it is possible to prevent the occurrence of disconnection or the like when used for a curved heat generating plate.

FIG. 1 is a diagram for explaining an embodiment according to the present invention, and is a perspective view schematically showing a vehicle provided with a heat generating plate. In particular, FIG. 1 schematically shows an automobile provided with a front window made of a heat generating plate as an example of a vehicle. FIG. 2 is a view of the heat generating plate as viewed from the normal direction of the plate surface. 3 is a cross-sectional view of the heat generating plate of FIG. FIG. 4 is a diagram showing a state before each member constituting the heat generating plate of FIG. 3 is stacked. FIG. 5 is a plan view of the conductive pattern sheet as viewed from the normal direction of the sheet surface, and is a plan view showing an example of the conductive pattern. FIG. 6 is a plan view of the conductive pattern sheet as viewed from the normal direction of the sheet surface, and is a plan view illustrating another example of the conductive pattern. FIG. 7 is a cross-sectional view corresponding to the line VII-VII in FIG. 5, and is a diagram illustrating an example of a cross-sectional shape of the conductive thin wire. FIG. 8 is a diagram for explaining an example of a method for producing a conductive pattern sheet. FIG. 9 is a diagram for explaining an example of a method of manufacturing a heat generating plate. FIG. 10 is a diagram for explaining an example of a method for manufacturing a heat generating plate. FIG. 11 is a diagram for explaining an example of a method of manufacturing a heat generating plate. FIG. 12 is a diagram for explaining a modification of the method for manufacturing the heat generating plate. FIG. 13 is a diagram for explaining a modification of the method for manufacturing the heat generating plate. FIG. 14 is a diagram for explaining a modification of the method for manufacturing the heat generating plate. FIG. 15 is a diagram for explaining a modification of the method for manufacturing the heat generating plate.

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

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

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

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

  1 to 15 are diagrams for explaining an embodiment according to the present invention. Of these, FIG. 1 is a diagram schematically showing an automobile equipped with a heat generating plate, FIG. 2 is a view of the heat generating plate viewed from the normal direction of the plate surface, and FIG. 3 is a heat generating of FIG. FIG. 4 is a cross-sectional view of the plate, and FIG. 4 is a view showing a state before each member constituting the heat generating plate of FIG. 3 is stacked.

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

  FIG. 2 shows the heat generating plate 10 viewed from the normal direction of the plate surface. Moreover, the cross-sectional view corresponding to the III-III line of the heat generating plate 10 of FIG. 2 is shown in FIG. The heating plate 10 includes a pair of curved glass plates 11 and 12, a conductive pattern sheet 20 disposed between the pair of curved glass plates 11 and 12, the glass plates 11 and 12, and the conductive pattern sheet 20. And bonding layers 13 and 14 for bonding. In the example shown in FIGS. 1 and 2, the heat generating plate 10 is curved, but in FIGS. 3, 11, 14, and 15, the heat generating plate 10 is generated for the sake of simplification and easy understanding. The plate 10 and the glass plates 11 and 12 are illustrated in a flat plate shape.

  The conductive pattern sheet 20 includes a sheet-like base material 30, a conductive pattern 40 formed on the base material 30, a wiring part 15 for energizing the conductive pattern 40, a conductive pattern 40 and a wiring part. 15 and a connecting portion 16 for connecting the terminal 15 to the terminal 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, and the conductive pattern 40 is heated by resistance heating. The heat generated in the conductive pattern 40 is transmitted to the glass plates 11 and 12 through the bonding layers 13 and 14, and the glass plates 11 and 12 are warmed. Thereby, the cloudiness by the dew condensation adhering to the glass plates 11 and 12 can be removed. Moreover, when snow and ice adhere to the glass plates 11 and 12, this snow and ice can be melted. Therefore, a passenger | crew's visual field is ensured favorable.

  As an example, in order to produce the heat generating plate 10, as shown in FIG. 4, a curved glass plate 11, a bonding layer 13, a conductive pattern sheet 20, a bonding layer 14, and a curved glass plate 12 are stacked in this order. By heating and pressurizing, the curved glass plate 11, the conductive pattern sheet 20, and the curved glass plate 12 are joined by the joining layers 13 and 14.

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

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

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

  The heating plate 10 is not limited to the illustrated example, and may be provided with other functional layers expected to exhibit a specific function. Further, one functional layer may exhibit two or more functions. For example, glass plates 11 and 12 of the heating plate 10, bonding layers 13 and 14, and a base material 30 of the conductive pattern sheet 20 described later. A function may be imparted to at least one of the flattening layer 18 and the thermoplastic resin sheet layer 19 described later. Examples of functions that can be imparted to the heating plate 10 include an antireflection (AR) function, a hard coat (HC) function having scratch resistance, an infrared shielding (reflection) function, an ultraviolet shielding (reflection) function, and a polarization function. An antifouling function and the like can be exemplified.

  Next, the conductive pattern sheet 20 will be described. The conductive pattern sheet 20 includes a sheet-like base material 30, a conductive pattern 40 provided on the base material 30, a wiring part 15 for energizing the conductive pattern 40, a conductive pattern 40 and a wiring part. 15 and a connecting portion 16 for connecting the terminal 15 to the terminal 15. The conductive pattern sheet 20 has substantially the same planar dimensions as the glass plates 11 and 12 and may be disposed over the entire heat generating plate 10, or on a part of the heat generating plate 10 such as the front portion of the driver's seat. May be arranged only.

  The sheet-like base material 30 functions as a base material that supports the conductive pattern 40. The base material 30 is an electrically insulating substrate that is transparent in general terms that transmits a wavelength in the visible light wavelength band (380 nm to 780 nm).

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

  Moreover, it is preferable that the base material 30 has a thickness of 0.03 mm or more and 0.15 mm or less in consideration of retainability of the conductive pattern 40, light transmittance, and the like.

  The conductive pattern 40 will be described with reference to FIGS. 5 and 6. 5 and 6 are plan views of the conductive pattern sheet 20 as viewed from the normal direction of the sheet surface. FIG. 5 is a diagram illustrating an example of an arrangement pattern of the conductive pattern 40. FIG. 6 is a diagram illustrating another example of the arrangement pattern of the conductive pattern 40.

  The conductive pattern 40 is energized from the power source 7 such as a battery through the wiring portion 15 and the connection portion 16 and generates heat by resistance heating. And when this heat | fever is transmitted to the glass plates 11 and 12 through the joining layers 13 and 14, the glass plates 11 and 12 are warmed.

  In the example shown in FIG. 5, the conductive pattern 40 is arranged in a mesh pattern in which the conductive thin wires 41 define a large number of openings 43. The conductive pattern 40 includes a plurality of connecting elements 44 extending between the two branch points 42 and defining an opening 43. That is, the conductive thin wires 41 of the conductive pattern 40 are configured as a collection of a large number of connection elements 44 that form branch points 42 at both ends. In particular, in the illustrated example, at the branch point 42, the three connection elements 44 are connected at an equal angle, so that a large number of honeycomb-shaped openings 43 of the same shape surrounded by the six connection elements 44 are defined. Yes.

  In the illustrated example, the conductive pattern 40 has a mesh pattern in which honeycomb-shaped openings 43 having the same shape are regularly arranged. However, the conductive pattern 40 is not limited to such a mesh pattern, and may be a triangle, a rectangle, or the like. Mesh pattern in which irregularly shaped openings 43 are irregularly arranged, such as a mesh pattern in which openings 43 of the same shape are regularly arranged, a mesh pattern in which irregularly shaped openings 43 are regularly arranged, and a Voronoi mesh Various mesh patterns such as patterns can be used.

  Furthermore, the pattern of the conductive pattern 40 is not limited to a mesh pattern. The conductive pattern 40 shown in FIG. 6 has a plurality of conductive thin wires 41 that connect the pair of connecting portions 16. In the illustrated example, each of the plurality of conductive thin wires 41 extends from one connection portion 16 to the other connection portion 16 in a wavy line pattern. The plurality of conductive thin wires 41 are arranged away from each other in a direction non-parallel to the extending direction of the conductive thin wires 41. In particular, the plurality of conductive thin wires 41 are arranged in a direction orthogonal to the extending direction of the conductive thin wires 41. Thereby, a gap 45 is formed between two adjacent conductive thin wires 41. Each thin conductive wire 41 may extend between the pair of connecting portions 16 in a pattern such as a straight line, a broken line, or a sine wave in addition to the wavy line pattern.

  Such conductive thin wires 41 of the conductive pattern 40 are formed of a conductive paste 50 including a conductive powder 51 and a binder resin 52, as shown in FIG.

  As the binder resin 52 of the conductive paste 50, any of a thermosetting resin, an ionizing radiation curable resin, and a thermoplastic resin can be used. On the other hand, as the conductive powder 51 of the conductive paste 50, metal powder such as gold, silver, copper, platinum, aluminum, chromium, molybdenum, nickel, titanium, palladium, indium, tungsten and alloys thereof, the surface is gold, Preferred examples include resin coated with metal such as silver, copper, platinum, aluminum, chromium, molybdenum, nickel, titanium, palladium, indium, tungsten and alloys thereof, or powder of non-metallic inorganic material, graphite powder, carbon black powder, etc. be able to. Further, the shape of the conductive powder 51 can be selected from various shapes such as a spherical shape, a spheroid shape, a polyhedron shape, a scale shape, a disk shape, and a fiber shape. The conductive paste 50 may include conductive powder 51 made of a plurality of materials and conductive powder 51 made of a plurality of shapes.

  The particle size of the conductive powder 51 in the conductive paste 50 can be 0.5 μm or more and 5 μm or less in terms of average particle size. This average particle diameter is an arithmetic average value of the diameter of the conductive powder 51 taken by optical microscopy or transmission electron microscopy, and is defined in the annex of JIS Z 8901: 2006 (test powder and test particles). The arithmetic average particle diameter measured by the method described above. Moreover, although content of the electroconductive powder 51 in the electroconductive paste 50 is arbitrarily selected according to the electroconductivity of the electroconductive powder 51 and the form of the powder, for example, the solid content of the electroconductive paste 50 is 100 parts by weight. Among these, the conductive powder 51 can be contained in the range of 50 parts by weight or more and 98 parts by weight or less.

  The conductive powder formed of metal or the conductive powder coated with metal contained in the conductive paste 50 exhibits a relatively high reflectance. Then, when light is reflected by the conductive thin wire 41 of the conductive pattern 40 formed by the conductive paste 50 including the conductive powder formed of metal or the conductive powder coated with metal, the light is reflected. Light may be visible and may obstruct the occupant's field of view. Further, when the conductive pattern 40 is visually recognized from the outside, the designability may be deteriorated. Therefore, a dark color material may be included in the conductive paste 50. As the dark material, a pigment or dye such as black, graphite powder, carbon black powder, or the like can be used. From the viewpoint of ensuring the conductivity of the conductive paste 50, it is preferable to use conductive graphite powder or carbon black powder.

  According to the conductive pattern 40 formed of the conductive paste 50 as described above, the conductive pattern 40 can be formed using a known printing technique such as intaglio printing described later. Therefore, the degree of freedom in pattern design of the conductive pattern can be improved. Further, since the conductive pattern 40 formed of the conductive paste 50 has flexibility, the conductive pattern 40 is sandwiched between a pair of curved glass plates, and thereby the conductive pattern 40 is partially stretched. However, it is possible to effectively prevent the conductive pattern 40 from being cracked or disconnected. Furthermore, since the conductive pattern 40 formed of the conductive paste 50 has a higher resistance than a conductive wire made of only metal, the thin conductive wire 41 forming the conductive pattern 40 is difficult to manufacture. The conductive pattern 40 can sufficiently generate heat without being.

  FIG. 7 is a cross-sectional view corresponding to the line VII-VII in FIG. 5, and is a diagram illustrating an example of a cross-sectional shape of the conductive thin wire 41. A plurality of conductive thin wires 41 forming the conductive pattern 40 are formed on the sheet-like substrate 30. In the illustrated example, the conductive thin wire 41 has a base end portion 41 b connected to the base material 30 and a tip end portion 41 a farthest from the base material 30. 7 along the sheet surface of the base material 30 in a cross section (hereinafter, also simply referred to as “main cut surface”) perpendicular to the extending direction (longitudinal direction) of the conductive thin wire 41. The width of the conductive thin wire 41 gradually becomes thinner as the distance from the substrate 30 increases. In other words, on the main cut surface, the width of the conductive thin wire 41 is gradually narrowed from the base end portion 41b toward the tip end portion 41a. The term “gradually narrowing” here means that the width of the conductive thin wire 41 as shown in FIG. 7 keeps changing so that the width gradually decreases from the base end portion 41b toward the tip end portion 41a. This includes not only the case where the width does not change in a part of the region but also the case where the width becomes thick. That is, when the main cut surface of the conductive thin wire 41 is viewed as a whole and globally, the width of the conductive thin wire 41 in the main cut surface changes so as to become narrower from the base end portion 41b toward the tip end portion 41a. What is doing is included in the “gradually narrowing” here.

  According to the conductive thin wire 41 having such a cross-sectional shape, the glass plate 11, the bonding layer 13, and the conductive pattern sheet 20 are laminated in this order, and the glass plate 11 and the conductive pattern sheet 20 are interposed via the bonding layer 13. Thus, it is possible to reliably embed the conductive thin wires 41 in the bonding layer 13 and to effectively prevent bubbles from remaining at the interface between the conductive pattern sheet 20 and the bonding layer 13.

  The width W of the base end portion 41b of the conductive thin wire 41 in the main cut surface, that is, the width W along the sheet surface of the base material 30 is 5 μm or more and 20 μm or less, and the height H of the conductive thin wire 41 in the main cut surface is That is, the height H along the normal direction to the sheet surface of the substrate 30 is preferably 5 μm or more and 20 μm or less. According to the conductive thin wire 41 having such dimensions, since the conductive thin wire 41 is sufficiently thinned, the conductive pattern 40 can be effectively invisible.

  The conductive pattern sheet 20 having the conductive pattern 40 (conductive thin wire 41) formed of the above-described conductive paste 50 can be produced by using, for example, an intaglio printing technique. With reference to FIG. 8, an example of a manufacturing method of the conductive pattern sheet 20 using the intaglio printing technique will be described.

  As shown in FIG. 8, a conductive pattern forming apparatus 60 includes a plate (so-called intaglio plate) 61 having a plate surface 62 in which concave portions 63 are formed in a pattern corresponding to the conductive pattern 40 (conductive thin wire 41) to be formed. And a nip roll 64 that presses the substrate 30 toward the plate surface 62 of the plate 61, a transport roll 65 that conveys the substrate 30 peeled from the plate 61, and the conductive paste 50 is supplied to the plate surface 62 of the plate 61. A pickup roll 66 and a doctor blade 68 for scraping off the excess conductive paste 50 adhering to the plate surface 62 are provided. In the example shown in FIG. 8, the plate 61 is formed as a roll-shaped plate having a plate surface 62 formed on the outer peripheral surface thereof. Further, at least a part of the outer peripheral surface of the pick-up roll 66 is disposed in a container 67 for storing the conductive paste 50 and is immersed in the conductive paste 50.

  By using such a conductive pattern forming apparatus 60, the step of forming the conductive pattern 40 is a step of filling a conductive paste 50 that forms the conductive pattern 40 in the concave portion 63 of the plate 61. A step of pressing the substrate 30 against the plate surface 62 of the plate 61 to bring the substrate 30 into close contact with the conductive paste 50 filled in the recess 63; and a plate surface 62 of the plate 61 together with the substrate 30 and the conductive paste 50. And releasing the mold.

  Hereinafter, each step will be described. First, the base material 30 is prepared. As shown in FIG. 8, the prepared base material 30 is then transported to the conductive pattern forming apparatus 60. At this time, a primer layer may be formed on the surface of the substrate 30 that faces the plate surface 62. According to the base material 30 on which such a primer layer is formed, the adhesion between the base material 30 and the conductive paste 50 can be effectively improved.

  In parallel with the preparation process of the base material 30, the conductive paste 50 that forms the conductive pattern 40 is filled in the concave portions 63 formed on the plate surface 62 of the roll-shaped plate 61. In the method shown in FIG. 8, when the pickup roll 66 rotates, the fluid conductive paste 50 contained in the container 67 adheres to the outer peripheral surface of the pickup roll 66. The conductive paste 50 attached to the outer peripheral surface of the pickup roll 66 is then transferred to the plate surface 62 of the roll-shaped plate 61 that faces the outer peripheral surface of the pickup roll 66. A doctor blade 68 is disposed on the downstream side of the pickup roll 66 along the movement path of the printing plate 62. The doctor blade 68 scrapes away the conductive paste 50 other than the concave portion 63 of the plate surface 62 so that the conductive paste 50 exists only in the concave portion 63 on the plate surface 62. As described above, as the binder resin 52 of the conductive paste 50, a resin such as a thermosetting resin, an ionizing radiation curable resin, or a thermoplastic resin can be used, and the resin has a fluidity rather than a cured state. Is supplied to the plate surface 62 of the plate 61.

  Next, the base material 30 described above is fed between the plate 61 and the nip roll 64 so as to face the plate surface 62 filled with the conductive paste 50 only in the concave portion 63. The base material 30 is pressed toward the plate surface 62 of the plate 61 by the nip roll 64. When the primer layer is formed on the surface facing the plate surface 62 of the base material 30, the primer layer of the base material 30 is pressed toward the plate surface 62 of the plate 61.

Thereafter, the base material 30 is kept in contact with the plate surface 62 of the plate 61, and as the plate 61 rotates,
It moves with the plate surface 62. When the primer layer is formed on the surface facing the plate surface 62 of the substrate 30, the primer layer can be cured by heating, irradiation with ionizing radiation, or the like during this movement.

  Next, the base material 30 is peeled from the plate surface 62 of the plate 61 on the downstream side along the movement path of the plate surface 62 of the plate 61. At this time, the conductive paste 50 is extracted from the recess 63 together with the base material 30.

  Thereafter, the conductive paste 50 on the substrate 30 is cured by a curing device (not shown). As described above, the conductive pattern sheet 20 having the conductive pattern 40 (conductive thin wire 41) formed of the conductive paste 50 is produced.

  According to the method for manufacturing the conductive pattern sheet 20 using intaglio printing as described above, the shape of the concave portion 63 formed on the plate surface 62 of the plate 61 is changed to a pattern corresponding to the conductive pattern 40 to be formed. By doing so, the conductive pattern 40 can be formed with high accuracy. Therefore, the degree of freedom in pattern design of the conductive pattern can be improved. Further, the conductive pattern sheet 20 is produced by a so-called roll-to-roll method in which the substrate 30 is supplied from the roll-shaped winding body to the conductive pattern forming apparatus 60 and the produced conductive pattern sheet 20 is wound up. be able to. Therefore, it is possible to improve manufacturing efficiency and reduce manufacturing costs.

  Further, in the conductive pattern sheet 20 obtained through such a process, the conductive fine wire 41 having the cross-sectional shape shown in FIG. A conductive thin wire 41 whose width gradually decreases from the base end portion 41 b toward the tip end portion 41 a on the cut surface can be formed on the substrate 30.

  Next, an example of a method for manufacturing the heat generating plate 10 will be described with reference to FIGS. 3 and 9 to 11. 9-11 is sectional drawing which shows an example of the manufacturing method of the heat generating plate 10 in order.

  First, as shown in FIG. 9, a base material 30 is prepared. The base material 30 is an electrically insulating base material that is transparent and is generally referred to as transmitting a wavelength in a visible light wavelength band (380 nm to 780 nm).

  Next, as shown in FIG. 10, the conductive pattern 40 (conductive thin wire 41) is formed on the base material 30 with the conductive paste 50, thereby producing the conductive pattern sheet 20. The conductive pattern 40 can be formed by intaglio printing using the conductive pattern forming apparatus 60 described above with reference to FIG. The conductive pattern 40 is not limited to the intaglio printing described above, and may be formed using other known printing methods such as screen printing.

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

  Next, with reference to FIG. 9, FIG. 10 and FIGS. 12-15, the modification of the manufacturing method of the heat generating plate 10 is demonstrated. 12-15 is sectional drawing which shows the modification of the manufacturing method of 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 with reference to FIGS. 9 and 10 in an example of the method for manufacturing the heating plate 10 described above.

  Next, as shown in FIG. 12, a planarization layer 18 is formed. The planarization layer 18 planarizes the irregularities formed by the conductive pattern 40 side surface 30a of the substrate 30 on the conductive pattern 40 side and the conductive thin wires 41 forming the conductive pattern 40, and the thermoplasticity described later. In the step of forming the resin sheet layer 19, it has a function of preventing bubbles from remaining between the thermoplastic resin sheet layer 19 and the conductive pattern sheet 20. For example, the planarizing layer 18 is formed by arranging a resin having fluidity on the surface of the conductive pattern sheet 20 on the side where the conductive pattern 40 is formed, so that two adjacent conductive layers forming the conductive pattern 40 are formed. The region between the thin fine wires 41 (the opening 43 or the gap 45 in the example shown in FIGS. 5 and 6) is filled so as to at least partially fill. This filled resin forms the planarization layer 18. After the planarization layer 18 is filled, it may be dried, cured, or temporarily cured by heating, irradiation with ionizing radiation, or the like.

  In particular, the region between the two adjacent conductive thin wires 41 forming the conductive pattern 40 is completely filled with the resin forming the flattening layer 18, and the thickness of the flattening layer 18 and the height H of the conductive thin wire 41 are measured. Can be made equal. In other words, the upper surface (surface opposite to the base material 30) of the planarizing layer 18 and the tip end portion 41a of the conductive thin wire 41 can be flush with each other. In addition, the thickness of the planarizing layer 18 may be larger than the height H of the conductive thin wire 41 without being limited thereto. That is, the resin may cover the upper part of the conductive thin wire 41 and the upper surface of the resin may be flattened to form the flattened layer 18. Furthermore, the thickness of the planarizing layer 18 may be smaller than the height H of the conductive thin wires 41. That is, the planarization layer 18 may be formed so as to partially fill a region between two adjacent conductive thin wires 41 forming the conductive pattern 40. Even with the planarization layer 18 having a thickness smaller than the height H of the conductive thin wire 41, the difference in height between the upper surface of the planarization layer 18 and the tip portion 41a of the conductive thin wire 41 is the flattening layer. 18 is smaller than the difference in height between the surface 30a of the base material 30 and the tip end portion 41a of the conductive thin wire 41 before the 18 is formed. Therefore, the remaining of air bubbles between the thermoplastic resin sheet layer 19 and the conductive pattern sheet 20 can be suppressed.

  As the resin for forming such a planarization layer 18, various resin materials having visible light permeability can be used. As a typical material, polyvinyl butyral (PVB) can be exemplified.

  Next, as shown in FIG. 13, the conductive pattern sheet 20 and the conductive pattern sheet are laminated by laminating a thermoplastic resin sheet on the conductive pattern sheet 20 from the side where the planarization layer 18 is provided. An intermediate member 70 having a flattening layer 18 provided on 20 and a thermoplastic resin sheet layer 19 laminated on the conductive pattern sheet 20 from the side on which the flattening layer 18 is provided is produced.

  Thereafter, the glass plate 11, the intermediate member 70, the bonding layer 14, and the glass plate 12 are superposed in this order, and heated and pressurized. In the example shown in FIG. 14, the bonding layer 14 is temporarily bonded to the glass plate 12. Next, the glass plate 11 is opposed to the thermoplastic resin sheet layer 19 of the intermediate member 70, and the side on which the bonding layer 14 of the glass plate 12 is temporarily bonded is opposed to the base material 30 of the intermediate member 70. 11, the intermediate member 70, and the glass plate 12 to which the bonding layer 14 is temporarily bonded are superposed in this order, and heated and pressurized. At this time, the thermoplastic resin sheet layer 19 functions as a bonding layer 13 for bonding the glass plate 11 and the conductive pattern sheet 20. Further, when the intermediate member 70 includes the planarizing layer 18 that is not completely cured, the planarizing layer 18 can also function as the bonding layer 13 that bonds the glass plate 11 and the conductive pattern sheet 20. Thus, the heat generating plate 10 shown in FIG. 15 is manufactured.

  As described above, the heating plate 10 in the present embodiment includes 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 the bonding layers 13 and 14 for bonding the glass plates 11 and 12 and the conductive pattern sheet 20 to each other, and the conductive pattern sheet 20 is a sheet-like substrate. 30 and a conductive pattern 40 provided on the substrate 30, and the conductive pattern 40 includes a conductive thin wire 41 made of a conductive paste 50. In addition, the conductive pattern sheet 20 in the present embodiment includes a sheet-like base material 30 and a conductive pattern 40 provided on the base material 30, and the conductive pattern 40 is formed from the conductive paste 50. Conductive thin wire 41 is included. According to the heat generating plate 10 and the conductive pattern sheet 20 as described above, the conductive pattern 40 can be formed using a known printing technique such as the intaglio printing described above. Therefore, the degree of freedom in pattern design of the conductive pattern can be improved. Further, since the conductive pattern 40 formed of the conductive paste 50 has flexibility, the conductive pattern 40 is sandwiched between a pair of curved glass plates, and thereby the conductive pattern 40 is partially stretched. However, it is possible to effectively prevent the conductive pattern 40 from being cracked or disconnected. Furthermore, since the conductive pattern 40 formed of the conductive paste 50 has a higher resistance than a conductive wire made of only metal, the thin conductive wire 41 forming the conductive pattern 40 is difficult to manufacture. The conductive pattern 40 can sufficiently generate heat without being.

  In addition, in the heat generating plate 10 in the present embodiment, in the cross section orthogonal to the longitudinal direction of the conductive thin wire 41, the width of the conductive thin wire 41 is the largest from the base material 30 from the base end portion 41 b connected to the base material 30. The taper gradually becomes thinner toward the distal end portion 41a. According to the heating plate 10 including the conductive thin wire 41 having such a cross-sectional shape, the glass plate 11, the bonding layer 13, and the conductive pattern sheet 20 are laminated in this order, and the glass plate 11 and the conductive pattern sheet 20 are laminated. When bonding via the bonding layer 13, the conductive thin wires 41 can be reliably embedded in the bonding layer 13, and effectively prevent bubbles from remaining at the interface between the conductive pattern sheet 20 and the bonding layer 13. can do.

  Moreover, the intermediate member 70 in this Embodiment is conductive from the conductive pattern sheet 20 described above, the planarization layer 18 provided on the conductive pattern sheet 20, and the side on which the planarization layer 18 is provided. And a thermoplastic resin sheet layer 19 laminated on the pattern sheet 20. Further, in the intermediate member 70 in the present embodiment, the planarization layer 18 at least partially fills the region between the two adjacent conductive thin wires 41 forming the conductive pattern 40. According to such an intermediate member, the unevenness formed by the surface 30a of the base material 30 on the side of the conductive pattern 40 and the conductive fine wire 41 forming the conductive pattern 40 in the conductive pattern sheet 20 is flattened, In the step of forming the plastic resin sheet layer 19, it is possible to effectively prevent bubbles from remaining between the thermoplastic resin sheet layer 19 and the conductive pattern sheet 20.

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

  For example, the conductive pattern 40 of the conductive pattern sheet 20 may be provided on the surface on the glass plate 12 side, not on the surface on the glass plate 11 side of the substrate 30. Moreover, you may provide in the both surfaces of the glass plate 11 side and the glass plate 12 side of the base material 30. FIG.

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

  Furthermore, the heat generating plate 10 can be used not only for a vehicle but also for a part that divides a room and an outdoor area, such as a building, a store, a house window, and the like.

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

DESCRIPTION OF SYMBOLS 1 Car 5 Front window 7 Power supply 10 Heat generating plate 11 Glass plate 12 Glass plate 13 Joining layer 14 Joining layer 15 Connecting part 16 Wiring part 18 Flattening layer 19 Thermoplastic resin sheet layer 20 Conductive pattern sheet 30 Base material 40 Conductive pattern 41 Conductive thin wire 42 Branch point 43 Opening 45 Gap 50 Conductive paste 51 Conductive powder 52 Binder resin 60 Conductive pattern forming device 61 Plate 62 Plate surface 63 Recess 64 Nip roll 65 Transport roll 66 Pickup roll 67 Container 68 Doctor blade 70 Intermediate member

Claims (1)

A heating plate that generates heat when a voltage is applied,
A pair of glass plates;
A conductive pattern sheet disposed between the pair of glass plates;
A bonding layer disposed between each glass plate and the conductive pattern sheet and bonding the glass plate and the conductive pattern sheet; and
The conductive pattern sheet has a sheet-like base material and a conductive pattern provided on the base material,
The conductive pattern is a heat generating plate including a conductive thin wire made of a conductive paste.

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