KR20200006229A - Heating film and method for manufacturing thereof - Google Patents

Abstract

A heating film according to one embodiment of the present application comprises a first adhesive film; a metal foil pattern disposed on the first adhesive film; and a resin layer in contact with at least part of a side of the metal foil pattern that is not in contact with the first adhesive film, wherein a refractive index of the resin layer is 1.45 to 1.49.

Description

Heat film and its manufacturing method {HEATING FILM AND METHOD FOR MANUFACTURING THEREOF}

The present application relates to a heat generating film and a method of manufacturing the same.

If there is a difference between the outside temperature and the inside temperature of the vehicle, moisture or frost is generated on the vehicle glass. In order to solve this, a heating glass may be used. The heat generating glass utilizes the concept of attaching a hot wire sheet to the glass surface or forming a hot wire directly on the glass surface, and applying heat to both terminals of the hot wire to generate heat from the hot wire, thereby raising the temperature of the glass surface.

In particular, there are the following methods as a method adopted to give a heat generating function while excellent optical performance to the windshield of the vehicle.

First, a transparent conductive thin film may be formed on the entire glass surface. The transparent conductive thin film may be formed by using a transparent conductive oxide film such as ITO or by forming a thin metal layer, and then increasing transparency by using a transparent insulating film above and below the metal layer. Using this method has the advantage of forming an optically excellent conductive film, but has a disadvantage in that it is not possible to implement a proper heat generation at a low voltage due to the relatively high resistance value.

Second, while using a metal pattern or wire (wire), it is possible to use a method of increasing the transmittance by maximizing the area without the metal pattern or wire. Typical products using this method are heating glass made by inserting tungsten wire into PVB film used for automobile windshield bonding. In the case of this method, the tungsten wire used has a diameter of 18 µm or more, so that a sufficient level of conductivity can be obtained at a low voltage. However, due to the relatively thick tungsten wire, the tungsten wire is visually visible. There are disadvantages.

Third, the metal pattern may be formed on the PET film through a printing process, or the metal pattern may be formed on the PET film through photolithography and etching. After inserting the PET film formed with the metal pattern between two sheets of PVB film, it is possible to make a heat generating product having a heat generating function through a glass bonding process.

Republic of Korea Patent Publication No. 10-2014-0140741

Herein, a heat generating film and a method of manufacturing the same are described.

One embodiment of the present application,

First adhesive film;

A metal foil pattern provided on the first adhesive film; And

A resin layer having a refractive index of 1.45 to 1.49 provided in contact with at least a portion of the surface not in contact with the first adhesive film of the metal foil pattern.

It provides a heating film comprising a.

In addition, another embodiment of the present application,

Forming a metal foil film on the first adhesive film;

Patterning the metal foil film to form a metal foil pattern;

Coating and drying the resin layer composition on a release film to form a resin layer;

Laminating the resin layer and the metal foil pattern

It provides a method for producing a heating film comprising a.

In addition, another embodiment of the present application,

First resin sheet; A resin layer having a refractive index of 1.45 to 1.49; And a heating film sequentially comprising a metal foil pattern,

A first glass provided on one surface of the heating film, and

It includes a second glass provided on the other side of the heating film,

The resin layer provides a heating glass for automobile that is provided in contact with at least a portion of the surface of the metal foil pattern.

In addition, another embodiment of the present application,

Second plastic substrate;

A first release layer provided on the second plastic substrate and having a release force of 5 gf / in to 70 gf / in; And

A resin layer provided on the first release layer, having a thickness of 3 μm to 50 μm and a refractive index of 1.45 to 1.49.

It provides a laminate for producing automobile heating glass comprising a.

According to the exemplary embodiment of the present application, the deposition process may be omitted by using a metal foil film without forming a metal pattern by an expensive deposition process as in the related art, and thus a heating film is manufactured at a low cost by reducing the fabric price. can do.

In addition, according to the exemplary embodiment of the present application, since the heatable metal foil pattern is directly supported on the roll-shaped PVB film instead of the PET film, the laminated glass based on the metal foil pattern without the PET film may be manufactured, thereby It may be advantageous for bonding with glass having a large curvature. In addition, it is possible to prevent the view distortion phenomenon caused by the difference in refractive index between the PET film and PVB, which is a conventional problem.

In addition, the heating glass for automobiles according to the exemplary embodiment of the present application uses a resin having the same refractive index as the interlayer of the laminated glass as the adhesion layer, so that even if the roughness of the metal foil film is high, the glass laminate After the haze is reduced can improve the optical properties.

1 to 4 are views schematically showing a heating film according to an exemplary embodiment of the present application.
5 to 7 are views schematically showing a heating glass for an automobile according to an exemplary embodiment of the present application, respectively.

Hereinafter, the present invention will be described in more detail.

Among the methods employed to provide excellent heat performance and excellent optical performance to the windshield, in the case of forming a metal layer on PET and then etching, if the thickness of the metal becomes thick, the seed layer is deposited and then plated. It should be formed by such a method, but the disadvantage is that the price is very high. In addition, most windshields are at least 1m and 1.4m high and wide, respectively. In addition, many of the cars have a height and width of more than 1.2m and 1.5m, respectively, and some of the larger models are more than 1.4m in height. In order to secure the driver's field of view, only an area of 1m × 1.2m is sufficient to generate heat. However, due to the size of the windshield, it is necessary to prepare, pattern or etch a fabric having a metal layer with a larger area than necessary. In addition, PET films that can be applied to special purposes, such as windshields, are more expensive than ordinary films. Therefore, when PET, which is actually applicable to windshields, is used from the metal patterning process, cost increase and yield drop may occur.

In addition, the metal layer in contact with the PET surface is a metal layer formed of a seed layer and a sputter of the thin film, which is smooth and shiny due to the low roughness of the surface. The unique reflectivity allows the pattern to be easily recognized.

When the metal foil is bonded with PET and an adhesive and then patterned, the fabric cost may be lowered. However, in this case, in order to secure the etching stability, the adhesive force must be excellent. Therefore, when the adhesive is completely cured, roughness corresponding to the surface roughness peculiar to the metal foil is formed on the surface of the adhesive, so that the haze of the film and the laminated glass. Has the disadvantage of increasing. In addition, since there is a difference in refractive index between PET and PVB, of course, when the laminated glass is made, each layer may be distorted due to the difference in refractive index. On the other hand, since PVB is a thermoplastic resin and PET has crystallinity and deformation characteristics due to heat are very different, bonding properties are not good when glass having a large curvature is used when bonding at high temperatures. As such, other layers in addition to the essential PET and metal may be added to complicate the structure and affect the properties of the final laminated glass.

Automotive glass companies usually prefer products with heating elements embedded on PVB films rather than separately supplying heating film and PVB film, and glass makers prefer to manufacture heating glass only by installing PVB and assembling bus bars. Prefer In this case, it is preferable to produce the product in the form of a roll in which the heating element is supported on the PVB. In order to be able to produce a rolled product in which a heating element is supported on a PVB film, roll lamination must be stable in a short time of at least 5 minutes.

After forming a metal foil pattern on the pressure-sensitive adhesive film has also been tried to transfer to the PVB sheet through a thermal lamination process. However, most of the known methods are to transfer the metal foil pattern on the pressure-sensitive adhesive film to the PVB sheet by pressing for a long time at high heat and pressure. For example, since it proceeds under conditions such as bonding under vacuum for at least 100 minutes at a temperature of 100 ° C. or more in a vacuum bonding machine, it is not easy to produce a product in which a metal foil pattern is supported on PVB in roll form. In addition, under such conditions of long-term high temperature and high pressure, the surface roughness inherent to the automotive PVB film is damaged, and thus, the air trapped inside is difficult to escape during the manufacturing of the laminated glass, thereby degrading the properties of the laminated glass.

In addition, after forming a PVB coating layer on the copper foil, the PVB coating surface is attached to the first protective film and patterned to form a metal foil pattern layer, and then the second protective film is laminated on the metal foil pattern layer, on the PVB coating layer It was proposed to produce, in roll form, a product in which a heating element is supported on a PVB sheet by using a product in which the formed metal foil pattern layers are each protected by the first and second protective films. However, in this case, it is difficult to precisely control the adhesion between the first protective film and the second protective film, and the processability varies greatly depending on the adhesion of the first protective film and the second protective film to the PVB coating layer / metal foil pattern layer. There was this. In addition, when the surface of the copper foil is shiny, if the PVB is coated on the shiny surface, the wet process essential for patterning was not smooth due to insufficient adhesion with the substrate, and the surface of the copper foil coating the PVB was matted through nodule treatment. Had to have a temper. In this case, when forming a metal foil pattern through copper foil etching after resist patterning, a copper residual film is easy to exist by a lower nodule, and in order to further etch the part, the material and process margin were narrow. If one surface has a matte surface by nodule treatment and the other surface is notodized, a copper foil having a shiny surface is used, and the patterning process is performed using a dry film photoresist (DFR). It should be coated with PVB and laminating the DFR on the shiny surface. DFR is usually difficult to process because the adhesion property on the shiny surface is weaker than the adhesion property on the matt surface.

Therefore, the present application is excellent in the heat generation characteristics at low voltage, and to provide a heat generating film integrated with the laminated film used in the laminated glass process for automobiles. In addition, the present application can be processed in the form of a roll film without a PET film, to provide a heating film and a heating glass for automobile including the metal foil pattern embedded in PVB.

Heat generating film according to an embodiment of the present application, the first adhesive film; A metal foil pattern provided on the first adhesive film; And a resin layer provided in contact with at least a portion of the surface not in contact with the first adhesive film of the metal foil pattern and having a refractive index of 1.45 to 1.49.

In one embodiment of the present application, the first adhesive film includes a first plastic substrate and a first adhesive layer provided on the first plastic substrate, and the first adhesive layer is provided in contact with the metal foil pattern. Can be.

The first plastic substrate is preferably a film having a light transmittance of 80% or more, such as polyethylene terephthalate (PET), cyclic olefin polymer (COP), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC), acetyl celluloid, and the like. In particular, the first plastic substrate is more preferably PET. The thickness of the first plastic substrate may be 50 μm to 125 μm, but is not limited thereto.

The first adhesive layer may include at least one of a silicon-based polymer and an acrylic polymer.

The peel strength of the first adhesive film may be 10gf / 25mm to 300gf / 25mm, and may be 15gf / 25mm to 100gf / 25mm. In the present application, the peel strength of the first pressure-sensitive adhesive film can be measured by the ASTM D3330 evaluation method.

When the peel strength of the first adhesive film is less than 10 gf / 25 mm, it may be difficult to stably support the metal foil when a process such as photolithography, development, metal etching, etc., is performed in a large roll-to-roll (R2R) area. In addition, when the peel strength of the first pressure-sensitive adhesive film exceeds 300gf / 25mm, it may be difficult to properly remove the first pressure-sensitive adhesive film at low tension without damaging other layers of the film.

In one embodiment of the present application, the metal foil pattern is provided on the first adhesive film.

The height of the metal foil pattern may be 2 μm to 15 μm, and the metal foil pattern may include an aluminum foil pattern or a copper foil pattern. At this time, the height of the metal foil pattern can be measured by a micrometer or a thickness gauge.

The metal foil pattern may be manufactured from a metal foil including at least one surface of a matt surface having a relatively high ten point average roughness Rz. At this time, the mat surface of the metal foil may be in contact with the first adhesive film.

In the present application, the reflectance of the metal foil at a wavelength of 380 nm to 780 nm measured on a mat surface having a relatively high ten point average roughness Rz may be 67% or less, 50% or less, or 30% or less. In addition, the metal foil pattern may include an aluminum foil pattern or copper foil pattern having an average reflectance of 15% or less at a wavelength of 380 nm to 780 nm.

The reflectance can be measured by equipment such as UV-3600 or Solidspec-3700 manufactured by Shimadzu, Japan.

The line width of the metal foil pattern may be 4 μm to 20 μm, and the sheet resistance may be 0.05 ohm / sq to 0.5 ohm / sq. In addition, based on the entire upper area of the first pressure-sensitive adhesive film, the upper area ratio of the first pressure-sensitive adhesive film provided with the metal foil pattern may be 20% or less, 10% or less, 1% to 20% , 1% to 10%. In addition, the total length of the lines of the metal foil pattern included in the area of 25cm ² may be 2m to 11m.

In one embodiment of the present application, the resin layer is provided in contact with at least a portion of the surface that is not in contact with the first adhesive film of the metal foil pattern, characterized in that the refractive index is 1.45 to 1.49. As for the refractive index of the said resin layer, it is more preferable that it is 1.47-1.48.

In the present application, the refractive index of the resin layer is a prism coupler (Prism Coupler (Couple equipment example-2010 / M of Metricon Corporation), an ellipsometer ((equipment example-UVISEL of Horriba Scientific), Abbe Refractometer (Equipment) Example-It can be measured by Kruss AR4). For example, using a prism coupler, the refractive index may be calculated by measuring a change in the amount of light reflected from the coating layer. More specifically, on the glass or other substrate having a known refractive index, the material to be measured for refractive index is coated by a method such as spin coating to a thickness of several μm, and then the coated sample is contacted with a prism. Subsequently, when the laser is incident on the prism, most of the total reflection occurs, but when a specific angle of incidence and a condition are satisfied, an evanescent field is generated at the interface and light is coupled. When the coupling occurs to measure the angle at which the intensity of light detected by the detector decreases rapidly, the prism coupler can automatically calculate the refractive index of the coating layer from the light polarization mode related parameters and the refractive indexes of the prism and the substrate.

In general, windshields are manufactured by inserting a laminated film between two sheets of glass and laminating them at high temperature and high pressure. In this case, polyvinyl butyral (PVB), ethyl vinyl acetate (EVA), etc. are mainly used as the bonding film, and the refractive index of these materials is 1.45 to 1.49, and most of them are 1.47 to 1.48. Since the haze can be reduced if the refractive index of the resin layer / laminated film is the same or there is little difference after the glass lamination, it is preferable to adjust the refractive index of the resin layer to 1.45 to 1.49. If the refractive index of the resin layer is largely different from the refractive index of the laminated film, light passes through the glass and has high haze due to internal scattering, which is more severe when the unevenness of the resin layer is large.

In addition, the resin layer may include at least one of polyvinyl butyral (PVB), ethylene vinyl acetate (EVA) and an acrylate polymer. In particular, it is more preferable that the resin layer contains polyvinyl butyral (PVB).

The glass transition temperature (Tg) of the resin layer may be 25 ℃ to 80 ℃, may be 25 ℃ to 60 ℃. When the glass transition temperature of the resin layer is less than 25 ° C, it is difficult to stably store the produced exothermic film at room temperature. In addition, when the exothermic film is laminated with the laminated film and the glass to be bonded at high temperature / high pressure, when the glass transition temperature of the resin layer is low, the fluidity is further increased, and the metal foil pattern is deformed to be more susceptible to tensile or disconnection. When the glass transition temperature of the said resin layer exceeds 80 degreeC, lamination by a lower base material and heat mentioned later is difficult.

The resin layer may be provided on at least some of the surfaces not in contact with the first adhesive film of the metal foil pattern, and may be provided on the entire surface not in contact with the first adhesive film of the metal foil pattern. In addition, at least a part of the resin layer may be provided in contact with the first adhesive film. In addition, the metal foil pattern may be embedded in the resin layer. As described above, in the exemplary embodiment of the present application, the resin layer may be provided only on a surface not in contact with the first adhesive film of the metal foil pattern to surround the surface of the metal foil pattern, and the resin layer Silver may be provided on the entirety of the first adhesive film and the metal foil pattern.

The thickness of the resin layer on the metal foil pattern, or the thickness of the resin layer on the first pressure-sensitive adhesive film may be independently 3 μm to 50 μm. More specifically, the resin layer may have a thickness of 3 μm to 50 μm, 3 μm to 30 μm, and 10 μm to 25 μm. When the thickness of the said resin layer exceeds 50 micrometers, the resin layer material is wasted unnecessary, and solvent drying is difficult and it is difficult to manufacture stably. In addition, after manufacturing the heating film, when the laminated film and glass on both sides of the heating film laminated at high temperature / high pressure when the metal foil pattern is deformed may be tensile or disconnection.

In one embodiment of the present application, the resin layer may be provided in conformal contact (conformal contact) on at least a portion of the surface that is not in contact with the first adhesive film of the metal foil pattern. In the present application, the conformal contact means that the resin layer is in contact with at least a portion of the surface that is not in contact with the first adhesive film of the metal foil pattern without voids. That is, according to the exemplary embodiment of the present application, the resin layer may completely cover the surface irregularities due to the surface roughness of the metal foil pattern without voids.

In one embodiment of the present application, a release film may be further included on the metal foil pattern and the resin layer.

The release film may include a second plastic substrate and a first release layer provided on the second plastic substrate, and the first release layer may be provided in contact with the resin layer.

The second plastic substrate is preferably a film having a light transmittance of 80% or more, such as polyethylene terephthalate (PET), cyclic olefin polymer (COP), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC), acetyl celluloid, and the like. In particular, the second plastic base material is more preferably PET.

The first release layer may include a silicone-based, melamine-based or norbornene-based polymer, or a mixture thereof.

The release force of the release film is not particularly limited as long as the coating of the composition for the resin layer on the release film is easy, and the resin layer coated on the release film by the thermal lamination process can then be transferred onto the metal foil pattern. More specifically, the release force of the release film evaluated by the peel force measured based on the TESA7475 tape may be 5gf / in to 70gf / in.

In addition, for smooth running or release property, the second plastic substrate or the first release layer may include fine protrusions.

The heating film according to the exemplary embodiment of the present application may further include a first resin sheet on the metal foil pattern and the resin layer. In addition, the heat generating film according to the exemplary embodiment of the present application, the metal foil pattern and the resin layer further comprises a first resin sheet, the metal foil pattern and the resin layer is provided embedded in the first resin sheet. Can be.

The heating film including the first resin sheet may be manufactured by removing the release film from the heating film including the release film and laminating the first resin sheet on the metal foil pattern and the resin layer.

The first resin sheet may not be adhered to the adherend itself, but may be a substrate to which adhesion may be imparted after thermal lamination with the adherend at a temperature of 40 ° C. to 120 ° C. More specifically, the first resin sheet may include a thermoplastic resin, and the thermoplastic resin may include one or more of polyvinyl butyral (PVB) and ethyl vinyl acetate (EVA). In addition, the first resin sheet may have a thickness of 100 μm to 800 μm, 100 μm to 400 μm, 400 μm to 800 μm, and 300 μm to 500 μm.

In an exemplary embodiment of the present application, the difference in refractive index between the resin layer and the first resin sheet may be 0.03 or less and zero or more.

In an exemplary embodiment of the present application, the resin layer means a layer formed by coating a composition for forming a resin layer, and the resin sheet means using a film form. In addition, as described above, the resin layer has a thickness of 3 μm to 50 μm, and the resin sheet has a thickness of 100 μm to 800 μm, and the like, and the resin layer and the resin sheet may be distinguished from each other.

In one embodiment of the present application, at least a portion of the metal foil pattern may further include a blackening layer. In addition, a blackening layer pattern may be further included in at least a portion between the metal foil pattern and the resin layer. At least a portion between the metal foil pattern and the resin layer may be a surface not in contact with the first adhesive film of the metal foil pattern, and more specifically, may be an upper surface and a side surface of the metal foil pattern. The blackening layer pattern may include one or more materials such as chromium series, selenium series, copper sulfide series, copper oxide series, copper nitride series, copper sulfide series, aluminum oxynitride series, and copper oxynitride series. The blackening layer pattern is formed by wet coating the above-described material on at least a part of the surface not in contact with the first adhesive film of the metal foil pattern, or a material such as aluminum oxynitride-based or copper oxynitride-based 30nm to It can be formed by sputtering process at 70nm.

The heating film according to the exemplary embodiment of the present application is schematically shown in FIGS. 1 to 4.

1, the heating film according to the exemplary embodiment of the present application has a structure in which the first adhesive film 10, the metal foil pattern 20, the resin layer 30, and the release film 40 are sequentially stacked. Can be.

In addition, as shown in Figure 2, the heating film according to an embodiment of the present application, the first adhesive film 10, the metal foil pattern 20, the resin layer 30 and the first resin sheet 50 are sequentially laminated It can have a structure.

In addition, as shown in FIG. 3, the heating film according to the exemplary embodiment of the present application may have a structure in which the metal foil pattern 20, the resin layer 30, and the first resin sheet 50 are sequentially stacked.

In addition, as shown in Figure 4, the heating film according to an embodiment of the present application has a structure in which the metal foil pattern 20, the resin layer 30 and the first resin sheet 50 are sequentially stacked, the metal foil pattern 20 may be embedded in the resin layer 30.

In addition, the method of manufacturing a heating film according to an embodiment of the present application, forming a metal foil film on the first adhesive film; Patterning the metal foil film to form a metal foil pattern; Coating and drying the resin layer composition on a release film to form a resin layer; And laminating the resin layer and the metal foil pattern.

In an exemplary embodiment of the present application, the contents of the metal foil film, the resin layer, the first adhesive film, the release film, and the like are the same as described above.

In an exemplary embodiment of the present application, the first adhesive film includes a first transparent substrate and a first adhesive layer provided on the first transparent substrate, and the first adhesive layer is provided to contact the metal foil film. You can.

In an exemplary embodiment of the present application, when the thickness of the metal foil film is 5 μm or less, the carrier layer may be introduced to the back of the metal foil film for ease of handling. The carrier layer may be a copper foil or an aluminum foil.

In an exemplary embodiment of the present application, the forming of the metal foil pattern by patterning the metal foil film may use a conventional resist patterning process known in the art. That is, after forming a resist pattern on the metal foil film, the metal foil pattern may be formed through an etching process.

The method of manufacturing a heating film according to an exemplary embodiment of the present application includes coating and drying a resin layer composition on a release film to form a resin layer. Coating the resin layer composition on the release film may use a comma coating, gravure coating, slot die coating and the like.

The method of manufacturing a heating film according to an exemplary embodiment of the present application includes laminating the resin layer and the metal foil pattern. More specifically, the laminating, the coating and dried resin layer surface and the metal foil pattern surface may be performed by a roll-to-roll thermal lamination process at a temperature of 40 ℃ to 120 ℃, the second release on the resin layer The film may be further formed, and the resin layer surface and the metal foil pattern surface may be performed by a roll-to-roll thermal lamination process at a temperature of 40 ° C. to 120 ° C. while removing the second release film. At this time, the second release film is to protect the resin layer, it is preferable that the release force of the release film directly coated with the composition for the resin layer is greater than the release force of the second release film.

The resin layer composition may include the aforementioned resin layer material and a solvent capable of dissolving it. The solvent is not particularly limited as long as it is a solvent capable of dissolving the resin layer material. For example, methanol, ethanol, isopropanol, methyl ethyl ketone, NMP, cellosolve material, a mixture thereof, and the like can be used.

Method of manufacturing a heating film according to an embodiment of the present application, after the step of laminating the resin layer and the metal foil pattern, removing the release film; Laminating a first resin sheet on the resin layer; And it may further comprise the step of removing the first adhesive film.

The laminating the first resin sheet on the resin layer may be performed by a roll-to-roll thermal lamination process at a temperature of 40 ° C. to 120 ° C. After the roll-to-roll thermal lamination process, the first resin sheet is in contact with the surface portion, the side portion, and the resin layer of the metal foil pattern, and the pores as much as possible by surface roughness due to the surface roughness of the metal foil pattern and the resin layer. It is desirable to have a conformal contact that covers the entire body without void. In addition, the first resin sheet may be provided in contact with the first adhesive film.

Removing the first adhesive film may be performed by a process of removing the first adhesive film after UV or heat irradiation.

In addition, the vehicle heating glass according to an embodiment of the present application, the first resin sheet; A resin layer having a refractive index of 1.45 to 1.49; And a heat generating film sequentially comprising a metal foil pattern, a first glass provided on one side of the heat generating film, and a second glass provided on the other side of the heat generating film, wherein the resin layer comprises the metal foil pattern It is provided in contact with at least a part of the surface.

In an exemplary embodiment of the present application, the first glass and the second glass are not particularly limited, and glass known in the art may be applied.

In an exemplary embodiment of the present application, the metal foil pattern and the resin layer may be provided embedded in the first resin sheet.

In an exemplary embodiment of the present application, a second resin sheet may be further included on at least one of a surface between the heating film and the first glass and a surface between the heating film and the second glass.

The second resin sheet may not be adhered to the adherend itself, but may be a substrate to which adhesiveness may be given after thermal lamination with the adherend at a temperature of 40 ° C. to 120 ° C. More specifically, the first resin sheet may include a thermoplastic resin, and the thermoplastic resin may include one or more of polyvinyl butyral (PVB) and ethyl vinyl acetate (EVA). In addition, the second resin sheet may have a thickness of 100 μm to 800 μm, 100 μm to 400 μm, 400 μm to 800 μm, and 300 μm to 500 μm. In addition, the first resin sheet and the second resin sheet may include the same material, or may include different materials.

In one embodiment of the present application, the haze of the heating glass for automobiles may be 0.3% to 2%.

According to an exemplary embodiment of the present application, it may further include a pair of opposing busbars for applying electricity to the metal foil pattern.

According to an exemplary embodiment of the present application, a black pattern may be provided to conceal the bus bar. For example, the black pattern may be printed using a paste containing cobalt oxide. At this time, screen printing is suitable for screen printing, the thickness can be set to 10㎛ to 100㎛. The metal pattern and the bus bar may be formed before or after the black pattern is formed, respectively.

Automotive heating glass according to an embodiment of the present application may be connected to a power source for heat generation, wherein the heat generation amount is preferably 100W to 1,000W, preferably 200W to 700W per m ² . Automotive heating glass according to an embodiment of the present application is excellent in heat generating performance of the heating element even at low voltage, for example, 30V or less, preferably 20V or less.

Automotive heating glass according to an exemplary embodiment of the present application is schematically shown in Figures 5 to 7 below.

5, the automotive heating glass according to the exemplary embodiment of the present application may include a first glass 70, a second resin sheet 60, a metal foil pattern 20, a resin layer 30, and a first resin sheet. 50 and the second glass 80 may have a stacked structure sequentially. In this case, the metal foil pattern 20 may further include a pair of bus bars 90. In addition, the thicknesses of the first resin sheet 50 and the second resin sheet 60 may be independently 100 μm to 400 μm.

In addition, as shown in Figure 6, the automotive heating glass according to an embodiment of the present application is the first glass 70, the second resin sheet 60, the first resin sheet 50, the resin layer 30, The metal foil pattern 20 and the second glass 80 may be sequentially stacked. In this case, the metal foil pattern 20 may further include a pair of bus bars 90. In addition, the thicknesses of the first resin sheet 50 and the second resin sheet 60 may be independently 100 μm to 400 μm.

In addition, as shown in Figure 7, the automotive heating glass according to an embodiment of the present application is the first glass 70, the first resin sheet 50, the resin layer 30, the metal foil pattern 20 and the second The glass 80 may have a stacked structure sequentially. In this case, the metal foil pattern may further include a pair of bus bars 90. In addition, the thickness of the first resin sheet 50 may be 400㎛ to 800㎛.

In FIGS. 5 to 7, since the glass is left at a high temperature and pressure for a long time, the space separated from the glass by the thickness of the metal foil pattern and the bus bar may be filled by the resin layer and the first resin sheet. Since the layer and the first resin sheet may all have the same refractive index, it may be difficult to distinguish the two after appearance of glass bonding. In addition, since the resin layers, the first resin sheet and the second resin sheet may all have the same refractive index, it may be difficult to distinguish the three after appearance of glass bonding.

In addition, the laminate for manufacturing a car heating glass according to an embodiment of the present application, the second plastic substrate; A first release layer provided on the second plastic substrate and having a release force of 5 gf / in to 70 gf / in; And a resin layer provided on the first release layer, having a thickness of 3 μm to 50 μm and a refractive index of 1.45 to 1.49.

According to the exemplary embodiment of the present application, the deposition process may be omitted by using a metal foil film without forming a metal pattern by an expensive deposition process as in the related art, and thus a heating film is manufactured at a low cost by reducing the fabric price. can do.

In addition, according to the exemplary embodiment of the present application, since the heatable metal foil pattern is directly supported on the roll-shaped PVB film instead of the PET film, the laminated glass based on the metal foil pattern without the PET film may be manufactured, thereby It may be advantageous for bonding with glass having a large curvature. In addition, it is possible to prevent the view distortion phenomenon caused by the difference in refractive index between the PET film and PVB, which is a conventional problem.

In addition, the heating glass for automobiles according to the exemplary embodiment of the present application uses a resin having the same refractive index as the interlayer of the laminated glass as the adhesion layer, so that even if the roughness of the metal foil film is high, the glass laminate After the haze is reduced can improve the optical properties.

Hereinafter, the exemplary embodiments described in the present specification will be described through examples. However, the scope of the embodiments is not intended to be limited by the following embodiments.

< Example >

< Example  1>

A coating liquid having a composition of 12 parts by weight of PVB sheet having a refractive index of 1.47 and a glass transition temperature (Tg) of 32 ° C., 44 parts by weight of ethanol, and 44 parts by weight of methyl ethyl ketone, was prepared in a release film having a thickness of 50 μm and a release force of 60 gf / in. After coating on the release layer and dried for 5 minutes at 120 ℃, to form a PVB coating layer of 23㎛ thickness.

Separately, a substrate was prepared by laminating a first adhesive film having a PET / adhesive layer structure having a peel strength of 60 gf / 25 mm measured by an evaluation method of ASTM D3330 on a matt surface of a copper foil of 12 μm in thickness. At this time, the surface roughness (Rz) of the matt surface of the 8 μm copper foil was 1.63 to 2.54 μm, and the first adhesive film used was a 7 μm thick silicon-based first adhesive layer coated on a 75 μm thick PET. Thereafter, the surface of the copper foil was washed / washed / dried with 0.5 wt% sulfuric acid, and a dry film resist (DFR) having a thickness of 15 μm was laminated at 110 ° C. on the copper foil surface. Thereafter, the first pressure-sensitive adhesive film / metal foil pattern layer film was prepared through a photolithography → development → etching → peeling process. At this time, 0.2 wt% aqueous solution of potassium carbonate was used, 20 wt% aqueous solution of iron chloride was used, and 2% aqueous solution of sodium hydroxide was used for the etching solution, and blackening solution was prepared by dissolving a selenium compound in an acidic aqueous solution based on phosphoric acid. The liquid was used. At this time, the line width of the copper foil pattern was 15 to 23 µm.

Thereafter, the first adhesive is formed by laminating a PVB coating layer surface of the release film / PVB coating layer film and a metal foil pattern surface of the first adhesive film / metal foil pattern layer film at a speed of 0.7 m / min at a temperature of 80 ° C. A film / metal foil pattern layer / PVB coating layer / release film product was produced. The release film was then removed from the PVB coating layer through a delamination process. Thereafter, the PVB coating layer surface of the first adhesive film / metal foil pattern layer / PVB coating layer film from which the release film was removed and the first PVB film having a thickness of 380 µm were attached by roll lamination on a rubber roll set at a temperature of 80 ° C. A structure of the first adhesive film / metal foil pattern layer / PVB coating layer / first PVB film was prepared.

Thereafter, after removing the first adhesive film from the structure, the first PVB film surface of (1) having the first adhesive film removed on the first glass is laminated so as to be in contact with the second glass surface, the first adhesive After removing the film, the first and second bus bars made of copper foil having a width of 1 cm and a thickness of 50 µm were mounted on both ends of the upper surface where the pattern surface of the metal foil pattern film was exposed. The second PVB film was laminated thereon, and the first glass was laminated thereon, followed by vacuum lamination at 120 ° C. for 20 minutes to prepare a exothermic laminated glass in which a copper pattern was embedded between PVBs. The sheet resistance of the exothermic laminated glass thus produced was 0.22 ohm / sq.

< Comparative example  1>

A first adhesive film having a peel strength of 173 gf / 25 mm was laminated on a matt surface having a surface roughness (Rz) value of 1.5 μm in 3 μm copper foil. At this time, the 3 micrometer copper foil used the product which the shiny surface was supported by the 18-micrometer-thick carrier copper foil, and removed the carrier copper foil before forming a pattern on a shiny surface. Then, a copper foil pattern layer was formed on the first pressure-sensitive adhesive film through copper foil surface pretreatment → resist pattern formation → etching → peeling process. Subsequently, the first PVB sheet was directly laminated with the first adhesive film / metal foil pattern layer film at a temperature of 80 ° C. to 120 ° C. without the release film / PVB coating layer formation and the transfer step of the PVB coating layer. Although the thickness was low as 3 μm, the adhesion of the first PVB sheet and the metal foil pattern layer was not good, and thus the first PVB sheet could not be roll-rolled (R2R) thermally laminated or the first adhesive film could not be removed smoothly. This was the same even when the peel strength of the first adhesive film was lowered to 30 gf / in.

According to the exemplary embodiment of the present application, the deposition process may be omitted by using a metal foil film without forming a metal pattern by an expensive deposition process as in the related art, and thus a heating film is manufactured at a low cost by reducing the fabric price. can do.

In addition, according to the exemplary embodiment of the present application, since the heatable metal foil pattern is directly supported on the roll-shaped PVB film instead of the PET film, the laminated glass based on the metal foil pattern without the PET film may be manufactured, thereby It may be advantageous for bonding with glass having a large curvature. In addition, it is possible to prevent the view distortion phenomenon caused by the difference in refractive index between the PET film and PVB, which is a conventional problem.

In addition, the heating glass for automobiles according to the exemplary embodiment of the present application uses a resin having the same refractive index as the interlayer of the laminated glass as the adhesion layer, so that even if the roughness of the metal foil film is high, the glass laminate After the haze is reduced can improve the optical properties.

10: first adhesive film
20: metal foil pattern
30: resin layer
40: release film
50: first resin sheet
60: second resin sheet
70: first glass
80: second glass
90: busbar

Claims (26)

First adhesive film;
A metal foil pattern provided on the first adhesive film; And
A resin layer having a refractive index of 1.45 to 1.49 provided in contact with at least a portion of the surface not in contact with the first adhesive film of the metal foil pattern.
Heating film comprising a. The exothermic film of claim 1, wherein the resin layer is provided on an entire surface of the metal foil pattern that is not in contact with the first adhesive film. The heating film of claim 1, wherein at least a part of the resin layer is provided in contact with the first adhesive film. The heating film of claim 3, wherein the metal foil pattern is embedded in the resin layer. The method according to claim 3, wherein the thickness of the resin layer on the metal foil pattern, or the thickness of the resin layer on the first pressure-sensitive adhesive film is 3 to 50㎛ each independently. The method according to claim 1, wherein the first adhesive film comprises a first plastic substrate and a first adhesive layer provided on the first plastic substrate,
The first adhesive layer is a heating film provided in contact with the metal foil pattern. The method according to claim 6, wherein the first adhesive layer is a heat generating film containing at least one of a silicone-based polymer and an acrylic polymer. The method according to claim 1, wherein the peel strength of the first pressure-sensitive adhesive film is a heat film 10gf / 25mm to 300gf / 25mm. The method of claim 1, wherein the metal foil pattern has a line height of 2㎛ to 15㎛,
The sheet resistance of the metal foil pattern is 0.05 ohm / sq to 0.5 ohm / sq exothermic film. The method of claim 1, wherein the metal foil pattern is a heating film comprising an aluminum foil pattern or a copper foil pattern. The method of claim 1, wherein the resin layer comprises at least one of polyvinyl butyral (PVB), ethyl vinyl acetate (EVA) and an acrylate polymer,
Glass transition temperature (Tg) of the resin layer is 25 ℃ to 80 ℃ exothermic film. The exothermic film of claim 1, further comprising a release film on the metal foil pattern and the resin layer. The method according to claim 12, wherein the release film comprises a second plastic substrate and a first release layer provided on the second plastic substrate,
The first release layer is a heating film provided in contact with the resin layer. The exothermic film of claim 1, further comprising a first resin sheet on the metal foil pattern and the resin layer. The exothermic film of claim 14, wherein the metal foil pattern and the resin layer are embedded in the first resin sheet. The method according to claim 14, wherein the first resin sheet comprises at least one of polyvinyl butyral (PVB) and ethyl vinyl acetate (EVA),
The thickness of the first resin sheet is a heating film that is 100㎛ to 800㎛. The exothermic film of claim 1, further comprising a blackening layer on at least a portion of the metal foil pattern. Forming a metal foil film on the first adhesive film;
Patterning the metal foil film to form a metal foil pattern;
Coating and drying the resin layer composition on a release film to form a resin layer;
Laminating the resin layer and the metal foil pattern
Method for producing a heating film comprising a. The method of claim 18, wherein the laminating the resin layer and the metal foil pattern is performed by a roll-to-roll thermal lamination process at a temperature of 40 ° C to 120 ° C. The method of claim 18, after laminating the resin layer and the metal foil pattern,
Removing the release film;
Laminating a first resin sheet on the resin layer; And
Method of producing a heating film further comprising the step of removing the first adhesive film. The method of claim 20, wherein the laminating the first resin sheet on the resin layer is performed by a roll-to-roll thermal lamination process at a temperature of 40 ° C to 120 ° C. First resin sheet; A resin layer having a refractive index of 1.45 to 1.49; And a heating film sequentially comprising a metal foil pattern,
A first glass provided on one surface of the heating film, and
It includes a second glass provided on the other side of the heating film,
The resin layer is a heating glass for automobile that is provided in contact with at least a portion of the surface of the metal foil pattern. The heating glass of claim 22, wherein the metal foil pattern and the resin layer are embedded in the first resin sheet. The heating glass of claim 22, further comprising a second resin sheet on at least one of a surface between the heating film and the first glass and a surface between the heating film and the second glass. The method of claim 24, wherein the second resin sheet comprises at least one of polyvinyl butyral (PVB) and ethyl vinyl acetate (EVA),
The second resin sheet has a thickness of 100㎛ to 400㎛ automotive heating glass. Second plastic substrate;
A first release layer provided on the second plastic substrate and having a release force of 5 gf / in to 70 gf / in; And
A resin layer provided on the first release layer, having a thickness of 3 μm to 50 μm and a refractive index of 1.45 to 1.49.
Laminate for manufacturing automobile heating glass comprising a.

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