JP6686799B2 - Vehicle glass device and method for manufacturing heating electrode sheet used in the device - Google Patents

Description

  The present invention relates to a glass device for vehicles such as automobiles, and more particularly to a glass device for vehicles that has a good visibility and is easy to manufacture, and a method for manufacturing a heating electrode sheet used in the glass device for vehicles.

BACKGROUND ART Conventionally, a technique has been developed in which a heating conductor made of a metal such as a nichrome wire is embedded in a windshield of an automobile and stretched over the windshield to remove frost adhering to the windshield (see, for example, Patent Document 1).
Further, the present applicant has proposed a glass device for vehicles, which has particularly good visibility and is easy to manufacture, as a glass device for vehicles such as automobiles (see Patent Document 2).

Japanese Utility Model Publication No. 64-28309 JP, 2005-20723, A

In the windshield (Patent Document 1) described above, the heating conductor containing the nichrome wire is installed between the glass parts (between the two glass substrates serving as the laminated glass). The work of manufacturing is not easy, and it is difficult to obtain a sufficient field of view with such a windshield.
Further, also in the vehicle glass device described in Patent Document 2, there is a case where fluctuation due to a light beam occurs, or there is a case where haze of an opening portion is increased and light transmittance is diminished, so that a better visibility is obtained. Was required.

  The present invention has been made in consideration of such a point, and an object thereof is to provide a glass device for a vehicle that has a good visibility and can quickly remove frost, and can be easily manufactured. To do.

The present invention has been made in view of the above objects, and provides an invention including the following [1] to [9].
[1] A vehicle glass device including a pair of glass substrates and an intermediate film and a heating electrode sheet interposed between the glass substrates,
The heating electrode sheet includes a transparent base material sheet and a patterned conductor having a patterned region made of metal filaments having a plurality of openings,
A glass device for vehicles, characterized in that the surface exposed in the opening has a center line average roughness (Ra) measured according to JIS B0601 (1994) of 0.05 μm or more and 0.5 μm or less.
[2] The patterned conductor has a pair of bus bar electrodes which are located outside the patterned region and do not include an opening, and each bus bar electrode functions as a connection terminal through which a current flows. Vehicle glass equipment.
[3] The vehicle glass device according to [1] or [2], wherein a blackening layer is formed on at least the front surface and the back surface of the metal wire in the patterned region by a blackening treatment.
[4] The vehicle glass device according to any one of [1] to [3], wherein a blackening layer is formed on the inner surface of each opening of the metal wire in the patterned region by a blackening treatment.
[5] The vehicle glass device according to any one of [1] to [4], wherein the metal filament is a copper filament and the transparent substrate sheet is a polyethylene terephthalate sheet.
[6] The vehicle glass device according to any one of [1] to [5], wherein the intermediate film between the glass substrate and the glass substrate is a transparent resin intermediate film containing a transparent resin that exhibits adhesiveness when heated and melted. .
[7] The vehicle glass device according to [6], wherein the transparent resin interlayer film is any one selected from polyvinyl butyral, polyurethane, and ethylene-vinyl acetate copolymer.
[8] The vehicle glass device according to [7], wherein the transparent resin intermediate film is polyvinyl butyral.
[9] A method of manufacturing a heating electrode sheet, which is interposed between a pair of glass substrates of a vehicle glass device via an intermediate film, the manufacturing method comprising:
(1) A step of forming a metal layer on one surface of the transparent substrate sheet via a conductive layer by a vacuum process, (2) Forming a patterned region and an opening in the formed metal layer by photolithography. Including steps,
The surface exposed in the opening is prepared so that the center line average roughness (Ra) measured by JIS B0601 (1994) satisfies 0.05 μm or more and 0.5 μm or less. Method for producing a heating electrode sheet used in a glass device for a vehicle.

  According to the present invention, it is possible to provide a glass device for a vehicle, which has a high light transmittance, a good visibility, and is easy to manufacture, and a method for manufacturing a heating electrode sheet used in the glass device for a vehicle.

The side sectional view for explaining one embodiment of the glass device for vehicles according to the present invention. It is explanatory drawing of a structure of one Example of the heating electrode sheet used for the glass device for vehicles of this invention. It is a top view for explaining the patterned conductor of the present invention. It is explanatory drawing of the structure of one Example of the laminated glass used for the glass device for vehicles of this invention of this invention.

  An embodiment of the present invention will be described below with reference to the drawings. In addition, in the drawings attached to the present specification, for convenience of illustration and understanding, the scale, the vertical and horizontal dimension ratios, etc. are appropriately changed and exaggerated from the actual ones.

  In the present specification, the terms “plate”, “sheet”, and “film” are not distinguished from each other based only on the difference in designation. For example, the "sheet" is a concept including members that can be called plates and films, and therefore, the "heating electrode sheet 10" is called a member called "conductive mesh plate" or "conductive mesh film". Can not be distinguished only in the difference of.

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

<< Vehicle glass device >>
An embodiment of a glass device for vehicles according to the present invention will be described below with reference to the drawings.

  The vehicle glass device 200 is composed of a windshield of an automobile, a rear glass of an automobile, a side glass of an automobile, a side glass of a ship, etc., and is mainly used in cold regions, and can easily remove adhered frost, snow, etc., and Has a good field of view.

As shown in FIG. 1, such a vehicle glass device 200 includes a pair of glass substrates 20, 20, an intermediate film 30 interposed between the pair of glass substrates 20, 20, and a heating electrode sheet 10. The heating electrode sheet 10 is composed of a transparent base material sheet 1 and a patterned area 4, and a patterned area 4 composed of a metal filament 2 and an opening 3 are formed on one surface of the transparent base material sheet 1. . The opening 3 has a center line average roughness (Ra) of 0.05 μm or more and 0.5 μm or less on the surface exposed in the opening 3 as measured according to JIS B0601 (1994).
The heating electrode sheet 10 is sandwiched between the glass substrates 20 and 20 with the intermediate films 30 and 30 interposed therebetween.

Of these, the glass substrate 20 is a normal glass substrate used for a windshield of an automobile or the like.
The glass substrate 20 may have a thickness of 500 μm to 10000 μm (1 cm). As the transparent material used for the glass substrate 20, for example, glass such as soda glass and potassium glass, transparent ceramics such as PLZT, and a transparent stone plate such as quartz and fluorite can be used. Although the glass substrate 20 is shown as a flat plate in FIG. 1, it is not limited to a flat plate in fact, and may be a curved plate curved with an appropriate curvature according to the target vehicle and its window.
The heating electrode sheet 10 has a patterned conductor portion 4 including a plurality of openings 3 defined by conductive metal filaments, and the transparent base material sheet 1 supporting the heating electrode sheet 10.

  Further, the heating electrode sheet 10 can have a pair of bus bar electrodes 4B located outside the patterned conductor 4. The opening 3 is not included in each bus bar electrode 4B.

  The patterned conductor 4 of the heating electrode sheet 10 has the patterned conductor 4 based on the metal filaments 2 that define the plurality of openings 3 (see FIGS. 2 and 3).

  Further, the heating electrode sheet 10 has a strip shape, and accordingly, the patterned conductor 4 and the transparent base material sheet 1 forming the heating electrode sheet 10 can also have a strip shape. In the strip-shaped patterned conductor 4, the patterned region extends in a strip shape at the center thereof, and a pair of bus bar electrodes 4B is formed at a pair of both ends of the patterned conductor 4. The plurality of heating electrode sheets 10 thus formed in a strip shape are interposed between the pair of glass substrates 20, 20 (not shown).

  Further, as shown in FIG. 1, the pair of bus bar electrodes 4B of each heating electrode sheet 10 protrudes outward from the pair of glass substrates 20, 20 and function as connection terminals for passing a current through the patterned conductor 4. To do.

  That is, in each of the heating electrode sheets 10 of the vehicle glass device 200, the DC power source 6 is externally connected to the pair of bus bar electrodes 4B functioning as connection terminals, so that the pattern conductor 4 of each heating electrode sheet 10 is connected. An electric current can be passed. As a result, each heating electrode sheet 10 generates heat due to the Joule heat, and frost, ice, snow, or the like adhering to the outer surface of the vehicle glass device 200 is melted or evaporated, and this is easily removed, which is excellent. The visibility can be secured.

  An example in which one heating electrode sheet 10 that covers the entire surface of the glass substrate is interposed between the pair of glass substrates 20 and 20 has been shown, but the present invention is not limited to this, and a glass between the pair of glass substrates 20 and 20 A plurality of single heating electrode sheets 10 having a smaller area than the substrate 20 may be interposed to cover the entire surface of the glass substrate.

<< Patterned conductor and heating electrode sheet >>
Next, the patterned conductor and the heating electrode sheet will be described in more detail. The patterned conductor 4 is a mesh-shaped material that defines a large number of openings 3. As shown in FIGS. 1 to 3, the patterned conductor 4 includes a large number of conductive metal strips 2 that extend between the two branch points 40 and define the openings 3. In particular, in the illustrated example, the patterned conductor 4 is configured as a group of a large number of metal filaments 2 forming branch points 40 at both ends. Then, at the branch point 40, the openings 3 are defined by connecting the metal filaments 2. In other words, one opening 3 is defined by being surrounded and divided by the metal wire 2.
Further, the metal filaments 2 surrounding one opening 3 serve as a unit lattice that constitutes a lattice.

  The patterned conductor 4 has electrical conductivity, exhibits some function related to electrical conductivity, and has visible light transmission through the opening 3. As shown in FIGS. 1 and 2, the patterned conductor 4 is formed on the transparent base material sheet 1 and forms the heating electrode sheet 10 together with the transparent base material sheet 1.

Here, a method of manufacturing the heating electrode sheet used in the vehicle glass device of the present invention will be described.
The method for producing a heating electrode sheet of the present invention includes (1) a step of forming a metal layer on one surface of a transparent base material sheet through a conductive treatment by a vacuum process, and (2) photolithography on the formed metal layer. Center line average roughness (Ra) measured by the method according to JIS B0601 (1994), including a step of forming a patterned region and an opening by a method of 0.05 μm or more and 0.5 μm or less. It is characterized in that it is prepared so as to satisfy.
Details of the manufacturing method will be appropriately described in the following description of embodiments of the configuration of the heating electrode sheet.

(Transparent substrate sheet)
The transparent substrate sheet is a layer for reinforcing the patterned conductor having weak mechanical strength. Therefore, as long as it has mechanical strength and light transmittance, the heat resistance and the like may be appropriately taken into consideration, and a material suitable for the application may be selected and used. Specific examples of the transparent substrate sheet include, for example, a resin plate, a resin sheet (or a film, the same applies hereinafter) and the like.

  Examples of the transparent resin used as a resin plate, a resin sheet or the like include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, terephthalic acid-isophthalic acid-ethylene glycol copolymer, terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer. Polyester resin such as nylon, polyamide resin such as nylon 6, polypropylene, polyolefin resin such as polymethylpentene, acrylic resin such as polymethylmethacrylate, polystyrene, styrene resin such as styrene-acrylonitrile copolymer, triacetyl Examples thereof include cellulose-based resins such as cellulose, imide-based resins, polycarbonate resins and the like.

These resins are used alone or as a mixed resin of a plurality of types (including a polymer alloy), and as a layer, they are used as a single layer or a laminate of two or more layers. In the case of a resin sheet, a uniaxially stretched or biaxially stretched stretched sheet is more preferable in terms of mechanical strength.
Further, additives such as an ultraviolet absorber, a filler, a plasticizer and an antistatic agent may be appropriately added to these resins, if necessary.

  The thickness of the transparent base material sheet may be determined according to the application, and is not particularly limited. When it is made of a transparent resin, it is usually about 12 to 1000 μm, but preferably 50 to 500 μm. Within these thickness ranges, the mechanical strength is sufficient, there is no warp, slack, breakage, etc., it is easy to supply and process in a strip shape without increasing the cost due to excessive performance, and the heating electrode sheet. The overall thickness can be reduced.

Further, in order to continuously manufacture the heating electrode sheet and improve the productivity, the transparent base material sheet is a laminated glass, and is laminated at a stage until it is cut into a predetermined shape in order to be laminated between a pair of glasses. It is preferable to handle in the form of a continuous strip-shaped sheet.
In this respect, a resin sheet is a preferable material for the transparent substrate sheet, but among the resin sheets, a polyester resin sheet such as polyethylene terephthalate or polyethylene naphthalate is particularly preferable because of its transparency, heat resistance and cost. The biaxially stretched polyethylene terephthalate sheet is most preferable in view of the above. The higher the transparency of the transparent base material, the better, but preferably the light transparency with which the visible light transmittance is 85% or more.

  The transparent substrate sheet 1 has a corona discharge treatment, a plasma treatment, an ozone treatment, a flame treatment, a primer (also referred to as an anchor coat, an adhesion promoter, and an easy adhesive) coating treatment and a pretreatment on the conductive treatment surface prior to the conduction treatment. Easy adhesion treatment such as heat treatment, dust removal treatment, vapor deposition treatment and alkali treatment may be performed. When the transparent substrate sheet is a resin film, additives such as a filler, a plasticizer and an antistatic agent may be added if necessary.

(Conductive treatment)
Conductive treatment is performed on the transparent substrate sheet 1 before forming a metal layer by metal electrolytic plating or the like. As a method of conducting the conductive treatment, a thin film of a known conductive material may be formed. The conductive material is, for example, a metal such as gold, silver, copper, iron, nickel, chromium, or an alloy containing at least one of these metals. Further, a transparent metal oxide such as tin oxide, ITO or ATO may be used. The conductive treatment may be a single layer or multiple layers, and these materials are formed as a conductive treated layer (not shown) by a known method such as a vacuum vapor deposition method, a sputtering method or an electroless plating method. The thickness of the conductive treatment layer may be an extremely thin layer of about 0.001 to 1 μm, as long as the required conductivity can be obtained during metal layer formation (plating or the like).

(Metal layer)
For example, a metal plating layer 21 is formed as a metal layer 2 on the surface of the conductive treatment layer to obtain a metal plating transparent base material sheet. As the material of the metal plating layer 21, for example, a metal having sufficient conductivity such as gold, silver, copper, iron, nickel, chromium, or the like, or an alloy containing one or more of these metals can be applied. . The metal plating layer 21 may be a single layer or a multi-layer, and copper or copper alloy is preferable from the viewpoint of ease of electrolytic plating and conductivity. Further, when a blackening layer and / or a chromate (treatment) layer is provided, copper or a copper alloy is preferable in terms of adhesion and the like. The thickness of the metal plating layer 21 is about 1 to 100 μm, preferably 5 to 15 μm. If the thickness is less than this, the mesh processing by the photolithography method will be easy, but the electrical resistance value of the metal will increase and there is a danger of disconnection, etc. Above this, the desired high-definition mesh shape cannot be obtained. As a result, the aperture ratio is substantially lowered, the light transmittance is lowered, the viewing angle is also lowered, and the visibility of the visual field is lowered.
Further, when forming the conductive treatment layer, a metal layer having a required thickness may be directly formed by a sputtering method or a vacuum deposition method. In this case, the thickness of the metal layer is about 0.5 to 5 μm, preferably 0.7 to 3 μm.

<Patterned conductor>
In the patterned conductor 4 having visible light transparency, the metal filaments 2 are hard to be visually recognized. On the other hand, the surface resistance of the patterned conductor 4 is a value suitable for heat generation so that the function expected due to the conductivity of the patterned conductor 4 can be sufficiently exerted. In the case of being used as a heating electrode sheet of a vehicle glass device, from the viewpoint that the patterned conductor 4 effectively exhibits the expected function, and the patterned conductor 4 has sufficient transparency, The patterned conductor 4 can be designed as follows. First, the line width of the metal filament 2 can be 30 μm or less, preferably 15 μm or less, more preferably 10 μm or less. The lower limit of the line width can be set to, for example, 1 μm or more, preferably 3 μm or more in order to avoid disconnection. In addition, the size of one opening 3 defined by the patterned conductor 4 formed using an opaque material can be set to 50 to 2000 μm. Here, the size of one opening 3 is an average of the maximum width and the minimum width of the opening 3 in plan view.

  The dimensions of the patterned conductor 4 such as the line width of the metal wire 2 and the size of the opening 3 do not need to be specified by examining the entire area of the patterned conductor 4 and calculating the average value thereof. , Practically, an object to be calculated in consideration of the size of each opening 3 defined by the metal wire 2 (the line width of the metal wire 2 and the size of the opening 3 etc. ) By calculating the average value by examining the number that is considered to be appropriate within a section having an area that is expected to reflect the overall tendency of Just specify. For example, in the patterned conductor 4 manufactured by the manufacturing method described later with the above design value as a target, 30 points included in a region of 30 mm × 30 mm are measured by an electron microscope to calculate an average. The line width of the metal wire 2 and the size of the opening 3 can be specified.

As the pattern of the patterned conductor constituting the heating electrode sheet of the present invention, among the following, the desired visible light transmittance, the invisibility of the metal filament, the degree of suppression of the light beam, etc. are taken into consideration. Select and adopt.
(1) As shown in FIG. 3, the metal filaments 3 have a lattice (mesh) shape in a plan view, and the unit lattice shape of the lattice is a triangle such as an equilateral triangle, an isosceles triangle, or a right triangle; a square or a rectangle. , Squares such as rhombus, parallelogram, trapezoid; hexagons such as regular hexagon, octagon, dodecagon, or n-gon such as decagon; geometric figures such as circles, ellipses, and stars. It is also possible to have a single repeating array of the unit lattices or a repeating array of a combination of two or more kinds of unit lattices. From the viewpoint of visible light transmittance, it is advantageous that, with the same line width, the larger the number of regular n-sided polygons, the higher the aperture ratio and the higher the visible light transmittance.
(2) As disclosed in Japanese Patent Laid-Open No. 2013-238029 and the like, each unit cell is formed of a mesh shape (Voronoi figure) in which a plane is Voronoi-divided based on generating points that are randomly distributed in the plane, and the shape and area of each unit lattice. Are different from each other in all or most of them, and each unit cell is irregularly arranged without having a constant array period in a specific direction.
(3) Extend a plurality of metal filaments having a straight-line shape or a waveform curve shape such as a sine wave in a plan view at predetermined intervals such that the extending directions of the filaments are parallel or substantially parallel to each other. A pattern of parallel straight line groups or parallel curved line groups that are arranged in a direction intersecting (for example, orthogonal to) the present direction. In order to reduce the generation of light rays, it is preferable to use parallel curve groups. In order to mitigate the influence of the decrease in heat generation due to the breakage of the metal wire, as disclosed in Japanese Patent Laid-Open No. 2011-210487, a metal forming parallel line groups adjacent to each other in the arrangement direction is used. It is preferable that a metal wire for connection that electrically connects the wires is provided (a so-called amida-like shape). The extending direction of the connecting metal filaments is the direction intersecting with the metal filaments forming the parallel wire group (for example, the direction orthogonal to the extending direction of the metal filaments forming the parallel wire group), and the parallel mutually adjacent The number of connecting metal wires to be provided between the metal wires forming the wire group depends on the size of the vehicle glass device, the required heat generation amount and the visible light transmittance, and during the manufacturing process and usage environment. Although it is set as appropriate in consideration of the frequency of disconnection, in the case of a front window of a general passenger car, it can be usually set to about 1 to 10 pieces.

Next, the step of forming the patterned conductor 4 on the transparent substrate sheet 1 by the photolithography method will be described.
First, a resist layer is provided on the metal layer on the transparent base material sheet 1 prepared as described above (not shown) to form a mesh pattern, and after removing the metal layer of the portion not covered with the resist layer by etching, The patterned conductor 4 having the mesh-shaped metal filaments 2 is formed by a so-called photolithography method for removing the resist layer.
According to this method, the existing equipment can be used, and many of these manufacturing steps are continuously performed, so that the quality is good, the production efficiency is high, the yield is good, and the production is inexpensive.

(masking)
First, the surface of the metal layer laminated on the transparent substrate sheet 1 is patterned by photolithography. In this step as well, it is preferable to process a roll-shaped laminated body that is continuously wound in a belt shape (referred to as winding processing or roll-to-roll processing). While the laminated body is continuously or intermittently transported, masking, etching, and resist stripping are performed in a stretched state without slack.

First, for masking, for example, a photosensitive resist is applied onto a metal layer that forms a mesh-shaped region as a pattern, dried, and then contact-exposed with a predetermined pattern plate (photomask), water-developed, and hardened. Treat and bake.
In addition, both a negative type and a positive type of the photosensitive resist can be used. When the photosensitive resist is a negative type, the mesh pattern of the pattern plate is a positive (positive image) with a transparent line portion. When the photosensitive resist is a positive type, the mesh pattern of the pattern plate is a negative with a transparent opening (negative image). The exposure pattern is a desired pattern for the heating electrode sheet, and as shown in FIG. 1, is composed of the patterned conductor 4 in the mesh region and the bus bar electrode 4B having no opening outside the mesh region. .

  In the winding process, the resist is applied by continuously or intermittently transporting a continuous strip-shaped laminate (a laminate of the transparent base material sheet 1 and the metal layer) to the metal layer surface forming the mesh-shaped region to the casein. A resist such as PVA, gelatin or the like is applied by a method such as dipping (immersion), curtain coating, or flowing over. Further, the resist may be a dry film resist instead of coating, and workability can be improved. In casein resist, baking is performed at 200 to 300 ° C., but it is preferable to keep the temperature as low as possible in order to prevent warpage of the laminate.

(etching)
Etching is performed after masking. As the etching solution used for the etching, a solution of ferric chloride or cupric chloride, which can be easily circulated when etching is continuously performed, is preferable. Further, the etching is basically the same process as equipment for manufacturing a shadow mask for a cathode ray tube of a color TV for etching a strip-shaped continuous steel material, particularly a thin plate having a thickness of 20 to 80 μm. That is, the existing manufacturing equipment for the shadow mask can be used, and continuous production can be performed consistently from masking to etching, which is extremely efficient. After etching, washing may be performed with water, resist removal with an alkaline solution, washing, and then drying. Since the transparent substrate is exposed on the surface of the mesh opening formed in this way, the mesh opening has good transparency.

  By the way, as shown in the sectional view of FIG. 2 (B), on the front surface and the back surface of the patterned conductor 4, on the metal wire 2 defining the opening 3, blackening is performed as shown in FIG. 2 (B). The layers 50a and 50b may be formed. In this case, after conducting the conductive treatment on the transparent base material sheet, it is subjected to the blackening treatment before laminating the metal layer, and the metal layer surface after the metal layer formation is subjected to the blackening treatment is used. By forming the patterned conductor 4 on the metal layer by etching, an electrode pattern having the blackened layers 50a and 50b on the front surface and the back surface of the patterned conductor 4 can be obtained.

  The blackened layers 50a and 50b formed on the patterned conductor 4 have an antireflection function and a function of improving the adhesiveness with an adjacent layer.

  Further, as shown in the sectional view of FIG. 2B, the inner surface of the opening 3 of the patterned conductor 4 may be blackened to form the blackened layer 50c.

<< laminated glass process >>
<Interlayer film>
The heating electrode sheet 10 obtained as described above has the intermediate films 30 and 30 interposed between the heating electrode sheet 10 and the pair of glass substrates 20 and 20 to adhere to the upper and lower sides thereof. The intermediate film 30 can be a transparent resin intermediate film selected from transparent resins that exhibit adhesiveness when heated and melted.
The transparent resin intermediate film that can be used in the present invention may be any selected from polyvinyl butyral, polyurethane, and ethylene-vinyl acetate copolymer. Among these, polyvinyl butyral is particularly preferable from the viewpoint that it has excellent penetration resistance against falling balls of laminated glass and has a track record of being used in many commercially available laminated glasses.

<< Operation of this Embodiment >>
Next, the operation of the present embodiment having such a configuration will be described.

  First, a plurality of heating electrode sheets 10 having the above-described patterned conductor 4 and the transparent base material sheet 1 supporting the patterned conductor 4 are prepared.

  Next, a plurality of heating electrode sheets 10 are interposed between the pair of glass substrates 20 and 20, and the pair of glass substrates 20 and 20 is provided with a transparent resin intermediate film 30 selected from transparent resins exhibiting adhesiveness by heating and melting. It is melted and solidified and fixed by adhesion. In this way, the vehicle glass device 200 can be easily manufactured. In this case, the pair of bus bar electrodes 4B of each heating electrode sheet 10 projects outward from the pair of glass substrates 20, 20.

  Next, the pair of bus bar electrodes 4B of the heating electrode sheet 10 projecting outward from the pair of glass substrates 20, 20 and the external DC power source 6 are connected. In this case, an electric current can be passed through the patterned conductors 4 of each heating electrode sheet 10, whereby the patterned conductors 4 generate heat and frost or snow adhered to the outer surface of the vehicle glass 200. Etc. can be removed.

  In addition, since each patterned conductor 4 has sufficient visible light transparency, even when the vehicle glass device 200 is used as a windshield of an automobile, the windshield is excellent in light transparency and has less light bleeding. As a result, a sufficiently excellent field of view can be obtained.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
<Preparation of heating electrode sheet>
(1) Production of Heating Electrode Sheet 1 The heating electrode sheet 10 shown in FIG. 2 was produced as follows. As the transparent substrate sheet 1, a continuous strip-shaped PET film A4300 (trade name of biaxially stretched polyethylene terephthalate film manufactured by Toyobo Co., Ltd.) having a thickness of 100 μm was prepared. A copper layer (conductive treatment layer) having a thickness of 0.5 μm was provided on one surface of the transparent substrate by a vacuum vapor deposition method to form a conductive treatment layer. A copper layer (metal plating layer) having a thickness of 10 μm was provided on the surface of the conductive treatment layer by electrolytic plating to form a metal plating layer, and a conductive material layer including the conductive treatment layer and the metal plating layer was formed on the transparent substrate. Thus, a copper-plated transparent base material sheet (metal-plated transparent base material sheet) was prepared. A mesh pattern was formed on the copper layer surface of the copper-plated transparent substrate by photolithography.
For the formation of the mesh pattern by the photolithography method, a production line for a color TV shadow mask, which performs masking to etching in a continuous strip shape, was diverted. First, a negative photosensitive resist of casein was applied over the entire surface of the conductive material layer by a pouring method. The film was conveyed to the next station, and contact exposure was performed using a pattern plate having a negative pattern (opening has a light-shielding property, and a line part has a light-transmitting property) having the following shape. While being transported through the stations one after another, water development was performed to leave a resist only in the exposed portion (corresponding to the opening portion), a film was hardened, and further baked at 100 ° C.
As for the shape of the pattern plate, the mesh portion has a square shape in plan view with an opening portion having a line width of 22 μm, a line interval (pitch) of 300 μm, and a bus bar electrode with no opening portion having a width of 5 mm formed on both ends in the longitudinal direction. (Not shown).
Further, it is conveyed to the next station, and by using a ferric chloride solution of 40 ° C and 40 ° Baume as an etching solution, it is sprayed by a spray method to corrode and remove only the conductive material layer in the non-resist portion, and the opening portion is formed. Was formed. Washing with water, peeling off the resist, washing, drying at 100 ° C., and cutting into desired dimensions, a heating electrode sheet was produced while successively transporting the stations. Hereinafter, this heating electrode sheet will be referred to as "heating electrode sheet 1".

(2) Manufacture of heating electrode sheet 2 In the manufacturing process of the above heating electrode sheet 1, a copper layer (conductive treatment layer) having a thickness of 0.5 μm provided on one surface of a transparent substrate by a vacuum deposition method A blackening layer made of copper-cobalt alloy particles having an average particle diameter of 0.3 μm was formed by the Dick electrodeposition method. The copper-plated transparent substrate sheet (metal-plated transparent substrate sheet) thus obtained was prepared. A heating electrode sheet 2 was produced by forming a mesh pattern on the copper layer surface of the copper-plated transparent substrate sheet with a blackening layer by a photolithography method in the same manner as the heating electrode sheet 1.

(3) Production of heating electrode sheet 3 Electrolytic metal foil having a thickness of 10 μm, in which a blackening layer made of copper-cobalt alloy particles having an average particle diameter of 0.3 μm and an anticorrosion layer made of a chromate (treatment) layer are added on one side. Using this, a chromate (treatment) layer surface of the copper-cobalt alloy particles and a PET film A4300 (trade name of biaxially stretched polyethylene terephthalate film manufactured by Toyobo Co., Ltd.) having a layer thickness of 100 μm are two-component curing type. After laminating with a polyurethane adhesive by a dry laminating method, it was aged at 56 ° C. for 4 days. As the adhesive, Takelac A-310, which is a polyol as a main agent, and A-10 (which is a trade name manufactured by Takeda Pharmaceutical Co., Ltd.), which is an isocyanate, are used as a curing agent, and the coating amount is 7 μm in a thickness after drying. did. The heating electrode sheet 3 was prepared in the same manner as the heating electrode sheet 1 for forming the mesh pattern by the photolithography method.

With respect to the obtained heating electrode sheets 1 to 3, the opening surface roughness, the reflectance, and the opening haze were evaluated using the following measuring methods.
(1) Surface roughness of opening (Ra)
It was measured based on JISB0601-1994 using a surface roughness measuring device (SE-3400) manufactured by Kosaka Laboratory Ltd. When measuring the opening surface roughness, in the state having the patterned conductor layer, the required measurement length cannot be obtained, so the measurement is performed in the state where the patterned conductor layer is removed as follows. It was
For each heating electrode sheet, one sample having a size of 20 cm × 20 cm was subjected to etching treatment with a ferric chloride solution to remove the patterned conductor layer, and then measured at arbitrary 5 points, and an average value thereof was obtained. Was defined as the surface roughness (Ra) of each opening.

(2) Reflectance (Y value)
Using a spectrocolorimeter (CM-3600d) manufactured by Konica Minolta Co., Ltd., total reflection (Y value) was measured in a D65 light source and a 10 ° visual field.
The metal layer portion of the bus bar electrode of the sample of each heating electrode sheet was measured at three locations, and the average value thereof was used as the reflectance.
Reflectivity less than 10 ・ ・ ・ ○
The reflectance exceeds 10 ... ×
When it is “◯”, the visibility of the visual field does not decrease, and good visibility is exhibited.

(3) Aperture Haze Measured with a haze meter (HM-150) manufactured by Murakami Color Research Laboratory. When measuring the opening haze, the measurement area required could not be obtained in the state where the patterned conductor layer was provided. Therefore, the measurement was performed in the state where the patterned conductor layer was removed as follows.
For each of the heating electrode sheets 1 to 3, one sample having a size of 20 cm × 20 cm was subjected to an etching treatment with a ferric chloride solution to remove the metal pattern layer, and then measured at arbitrary 5 points, and the average value thereof was measured. The haze of the opening.
Haze 10 or less
Haze exceeds 10 ... ×
When it is “◯”, the visibility of the visual field does not decrease, and good visibility is exhibited.

  Table 1 shows the evaluation results of the heating electrode sheets 1 to 3 by the above measuring method.

<Production of laminated glass>
It relates to Example 1 (using the heating electrode sheet 1), Example 2 (using the heating electrode sheet 2), and Comparative Example 1 (using the heating electrode sheet 3) described below using the above heating electrode sheet. A laminated glass was actually manufactured. As shown in FIG. 1, the laminated glass includes a first glass plate 20, a first intermediate film 30, a heating electrode sheet 10, a second intermediate film 30 bonding layer, and a second glass plate 20. I included it in order. In each laminated glass, the same first and second glass plates and the same first and second bonding layers were used. Specifically, as the first and second glass plates, curved blue plate glass plates having a length of 100 mm, a width of 100 mm and a thickness of 2 mm were used. A layer made of polyvinyl butyral (PVB) having a length of 100 mm, a width of 100 mm, and a thickness of 0.4 mm was used as the first and second intermediate films (bonding layers).

(Evaluation)
The distance between the halogen lamp (power of 100 W) as a light source and the laminated glass of Examples 1 and 2 and Comparative Example 1 was set to 5 m, and a distance of 60 cm from the laminated glass to the opposite side of the halogen lamp was observed. It was The laminated glass is installed in a posture in which the upper side is inclined to the observer side by 40 °, assuming the windshield of an automobile, and the distances of 40 cm and 60 cm are measured at the center of the inclined laminated glass. is there. Further, the 20 cm area of the portion directly hit by the light source was covered with black paper, and white turbid light generated in the peripheral portion was observed.

  As a result, white turbid light was not observed in the laminated glass of Examples 1 and 2. Next, in the laminated glass of Comparative Example 1, white turbid light was observed in the same evaluation as above, and the visibility of the visual field was poor.

  From the above, the center line average roughness (Ra) measured by the surface of the opening of the heating electrode sheet according to JIS B0601 (1994) is 0.05 μm or more and 0.5 μm or less. It was confirmed that there was no occurrence of the phenomenon and the visibility of the visual field was excellent.

  INDUSTRIAL APPLICABILITY The vehicle glass device of the present invention can be used as a vehicle glass device that has a sufficiently excellent field of view and can quickly remove frost, snow, and the like.

1 Transparent Base Material Sheet 2 Metal Wire 2'Metal Layer 3 Opening 4 Patterned Conductor (Mesh Area)
4B Bus bar electrode 6 DC power supply 10 Heating electrode sheet 20 Glass substrate 21 Plating layer 30 Intermediate film 40 Branch points 50a, 50b, 50c Blackening layer (rust prevention layer)
100 laminated glass 200 vehicle glass equipment

Claims (9)

In a vehicle glass device comprising a pair of glass substrates and an intermediate film and a heating electrode sheet interposed between the glass substrates,
The heating electrode sheet includes a transparent base material sheet and a patterned conductor having a patterned region made of metal filaments having a plurality of openings,
A glass device for vehicles, characterized in that the surface exposed in the opening has a center line average roughness (Ra) measured according to JIS B0601 (1994) of not less than 0.05 μm and not more than 0.5 μm.   The vehicle according to claim 1, wherein the patterned conductor has a pair of bus bar electrodes that are located outside the patterned region and do not include an opening, and each bus bar electrode functions as a connection terminal through which a current flows. Glass equipment.   The vehicle glass device according to claim 1, wherein a blackening layer is formed on at least a front surface and a back surface of the metal filament in the patterned region by a blackening treatment.   The vehicle glass device according to any one of claims 1 to 3, wherein a blackening layer is formed on the inner surface of each opening of the metal filament in the patterned region by a blackening treatment.   The vehicle glass device according to claim 1, wherein the metal filament is a copper filament and the transparent substrate sheet is a polyethylene terephthalate sheet.   The vehicle glass device according to any one of claims 1 to 5, wherein the intermediate film is a transparent resin intermediate film containing a transparent resin that exhibits tackiness when heated and melted.   The vehicle glass device according to claim 6, wherein the transparent resin intermediate film is any one selected from polyvinyl butyral, polyurethane, and ethylene-vinyl acetate copolymer.   The vehicle glass device according to claim 7, wherein the transparent resin intermediate film is polyvinyl butyral. A method of manufacturing a heating electrode sheet interposed between a pair of glass substrates of a vehicle glass device via an intermediate film,
The manufacturing method is
(1) A step of forming a metal layer on one surface of the transparent substrate sheet through a conductive treatment by a vacuum process,
(2) a step of forming a patterned region and an opening in the formed metal layer by photolithography,
The surface exposed in the opening is prepared so that the center line average roughness (Ra) measured by JIS B0601 (1994) satisfies 0.05 μm or more and 0.5 μm or less. Method for producing a heating electrode sheet used in a glass device for a vehicle.