KR20220095556A - Glass laminate - Google Patents

Abstract

The present invention relates to a glass laminate body comprising a form in which a first glass plate, a copper thin film, a heating film, and a second glass plate are sequentially laminated, the heating film comprises a base layer and a heating coating layer laminated on one surface of the base layer, the heating coating layer comprises a nanowire having an average length of 10-40 nm and an average thickness of 50-300 nm, and the copper thin film conducts a current from a voltage application device. Therefore, the present invention is capable of enabling even the frost that occurs on a large area to be removed in a short time.

Description

Glass laminate {GLASS LAMINATE}

The present invention relates to a glass laminate that has a simple manufacturing process including a heating film, can reduce manufacturing cost, and is effective for defrosting.

In winter or on rainy days, frost occurs on the car glass due to the temperature difference between the outside and the inside of the car. In order to solve the frost generated on such automobile glass, a heating glass has been proposed. Conventional heating glass removes frost by attaching a heating film to the glass surface or forming a heating wire directly on the glass surface, and then applying electricity to both terminals of the heating wire to generate heat from the heating wire, thereby raising the temperature of the glass surface. In order to generate heat smoothly, conventional heating glass was manufactured through a process of manufacturing a heating layer by sputtering a transparent conductive material such as ITO (Indium Tin Oxide) or Ag thin film. In addition, as another method of manufacturing the heating layer, a fine pattern that is difficult to recognize with the naked eye was formed on the surface of the glass by a photolithography method or the like. In particular, in the case of the wiper area, a thin metal wire was connected in parallel to a bus bar applied in the plane, and a voltage was applied to the wire to remove the frost of the wiper area.

Specifically, Korean Patent Registration No. 1865441 (Patent Document 1) describes; a transmittance control layer provided on the substrate and including Ni; And a heating element comprising a conductive heating pattern provided on the transmittance control layer is disclosed. However, the conventional heating glass such as Patent Document 1 has a problem of high cost and low efficiency because its manufacturing process is complicated and raw materials are wasted. In particular, the heating glass, which obtains a heating effect using a wire, has a problem in that a micro-thin metal wire is disconnected and a problem in that it is difficult to remove the frost in a short time because the heat is generated in the shape of the wire.

Therefore, it is possible to reduce the manufacturing cost because the manufacturing process is simple and there is little waste of raw materials, and it prevents the problem of disconnection and long time for defrosting because it does not use a thin metal wire, so that it is possible to prevent the problem of long time to remove the frost. There is a need for research and development on a glass laminate that can be removed in a short time.

Korean Patent Registration No. 1865441 (published on April 4, 2016)

Therefore, the present invention can reduce the manufacturing cost because the manufacturing process is simple and the waste of raw materials is small, and it does not use a thin metal wire, so it prevents the problem of disconnection and the problem that takes a long time to remove the frost, so that it can be applied to a large area An object of the present invention is to provide a glass laminate that can be removed in a short time even in the generated frost.

The present invention includes a form in which a first glass plate, a copper thin film, a heating film, and a second glass plate are sequentially laminated,

The heating film includes a substrate layer and a heating coating layer laminated on one surface of the substrate layer,

The exothermic coating layer includes nanowires having an average length of 10 to 40 nm and an average thickness of 50 to 300 nm,

The copper thin film conducts an electric current from a voltage application device, and provides a glass laminate.

The glass laminate according to the present invention has a simple manufacturing process and less waste of raw materials, so it is possible to reduce manufacturing costs. It can be removed in a short time even on a large area.

1 is a schematic front view of a glass laminate according to an embodiment of the present invention applied to the windshield of an automobile.
2 and 3 are cross-sectional views AA′ of a glass laminate according to an embodiment of the present invention.
4 is a measurement result of the surface temperature change according to the voltage application time to the glass laminate of Example 1.

Hereinafter, the present invention will be described in detail.

In the present specification, when a part "includes" a certain component, this means that other components may be further included rather than excluding other components unless otherwise stated.

In addition, in this specification, when a member is said to be located "on" another member, this includes not only a case in which a member is in contact with another member but also a case in which another member is present between the two members.

The glass laminate according to the present invention includes a form in which a first glass plate, a copper thin film, a heating film, and a second glass plate are sequentially laminated.

1 to 3, the glass laminate of the present invention includes a form in which the first glass plate 100, the copper thin films 210 and 220, the heating film 300 and the second glass plate 400 are sequentially stacked. do.

For example, the glass laminate may be a windshield of an automobile.

1st glass plate and 2nd glass plate

The first glass plate and the second glass plate serve as a base substrate of the glass laminate.

In this case, as the first glass plate and the second glass plate, conventional glass such as soda-lime glass, low iron glass, green plate glass, or blue plate glass used for automobiles may be used.

As the first glass plate and the second glass plate, a glass having an appropriate thickness may be used according to the purpose of use. For example, as the first glass plate and the second glass plate, transparent glass having an average thickness of 0.5 to 10 mm, or 1 to 5 mm may be used independently of each other.

Specifically, the first glass plate may be a transparent glass that is installed to face the external environment of the vehicle and has an average thickness of 0.5 to 5 mm, or 1 to 3 mm. That is, the first glass plate may be an outer glass of a vehicle.

In addition, the second glass plate may be, specifically, a transparent glass that is installed to face the inner environment of the vehicle and has an average thickness of 0.5 to 5 mm, or 1 to 3 mm. That is, the second glass plate may be an inner glass of a vehicle.

copper thin film

The copper thin film serves as an electrode for allowing current to flow through the heating film due to voltage application.

The copper thin film conducts current from the voltage applying device. That is, the glass laminate according to the present invention does not include a separate contact medium between the voltage application device and the copper thin film, for example, a contact strip, a foil conductor, a conductive structure, and the like. Through this, the glass laminate of the present invention has the advantage of simplifying the manufacturing process by not arranging an additional electrode on the heating film. In addition, since a thin metal wire is not used, the problem of being disconnected and the problem of taking a long time to remove the frost are prevented, so that the frost generated over a large area can be removed in a short time.

In addition, the copper thin film may be laminated on a portion of one surface of the first glass plate. Referring to FIG. 2 , the copper thin films 210 and 220 may be formed on a portion of one surface of the heating film 300 . That is, the copper thin film may have a smaller total area than the heating film. Specifically, the copper thin film may have a narrower width than the heating film, and referring to FIG. 2 , the width C of the copper thin films 210 and 220 may be narrower than the width H of the heating film.

In this case, the width (C) of the copper thin film may be 8 to 15 mm, or 10 to 15 mm. When the width of the copper thin film is less than the above range, there is a problem in that overheating occurs in the copper thin film itself (aka hot spot phenomenon), or current movement from the copper thin film to the coating layer is not smoothly performed. There may be a problem in that the cost increases due to the size of the copper thin film.

The copper thin film may have an average thickness of 5 to 150 μm, or 50 to 100 μm. When the average thickness of the copper thin film is less than the above range, the copper thin film and the heating film are overheated and thus cannot be applied to automobile glass, and there is a problem that heat is transferred to the bonding film that bonds the inner and outer glass to generate air bubbles, When it exceeds the above range, the current movement to the heating film is not smooth, so that heat is generated in the copper thin film and there may be a problem that the heating film is not heated.

In addition, two copper thin films may be disposed to be spaced apart. 1 and 2, the glass laminate includes a form in which the first glass plate 100, the copper thin films 210, 220, the heating film 300 and the second glass plate 400 are sequentially stacked, The copper thin films 210 and 220 may be disposed to be spaced apart from each other. Specifically, the copper thin film may include an upper copper thin film 210 and a lower copper thin film 220 that are spaced apart from each other.

In this case, the average distance (D) between the two copper thin films may be 55 to 150 mm, or 80 to 120 mm. When D is less than the above range, that is, when the distance between the copper thin films is narrow, there is a problem that overheating occurs due to excessive current flow. Problems can arise that cause insufficient heat.

The two copper thin films arranged to be spaced apart may have the same length or different lengths. In this case, the length (L) of the copper thin film means the length of the copper thin film in the region where the heating film is laminated. For example, referring to FIG. 1 , the copper thin films 210 and 220 may have a length L of 700 to 1500 mm or 800 to 1000 mm. Specifically, the two copper thin films arranged to be spaced apart may each independently have a length of 700 to 1500 mm or 800 to 1000 mm.

In addition, the length (L) of the upper copper thin film and the average distance (D) between the upper copper thin film and the lower copper thin film may be 5 to 9: 1, or 7 to 8.5 : 1. In this case, the length of the upper copper thin film is L, and the average distance between the two copper thin films is D (see FIGS. 1 and 2 ). When the ratio of L and D is less than the above range, there is a problem that heat is not generated in the heating film due to insufficient current flow. This can be difficult.

Since the film resistance increases with the length of the current path, in order to obtain the maximum possible heat output, the average distance between the upper and lower copper thin films must be at least a certain distance (hereinafter, referred to as 'minimum distance'). In order to defrost the winter frozen wiper and the area around it, the minimum distance must be able to cover the area. In order to defrost a frozen wiper through the heat of the heating film, it is desirable to have an appropriate heat output, and in the case of an abnormal heat output, it may have a negative effect on the heating film and glass located in the wiper area. When the amount of power per area of the heating film is 700 to 1200 W/m ² , it is appropriate to defrost the wiper area frozen from the outside temperature in winter. In addition, the applied voltage of the vehicle is 12 to 48 V, and when the heat of 1300 W/m ² at 13.5 V is generated, the glass in the wiper area frozen at -20 ° C for about 3 hours can be defrosted to about 70 ° C within 20 minutes. .

fever film

The heating film includes a substrate layer and a heating coating layer laminated on one surface of the substrate layer.

Referring to FIG. 2 , the heating film 300 includes a substrate layer 320 and a heating coating layer 310 laminated on one surface of the substrate layer 320 . Specifically, the glass laminate may include a form in which the first glass plate 100, the copper thin films 210 and 220, the heat-generating coating layer 310, the base layer 320, and the second glass plate 400 are sequentially stacked. can

base layer

The base layer serves as a base material for the heating film and maintains its shape.

The base layer may be a plastic substrate or a film commonly used, for example, PET (polyethylene terephthalate), PI (poly imide), PEN (polyethylene naphthalate), PP (polypropylene), PC (polycarbonate), etc. can be heard

In addition, the base layer may have an average thickness of 50 to 500 μm, or 80 to 120 μm. When the average thickness of the base layer is less than the above range, there may be a problem that the shape is not maintained. When the average thickness of the base layer exceeds the above range, the ductility of the base layer is insufficient, so that the surface is wrinkled without bonding in the same shape according to the curvature of the glass, or an empty space around the heating film is generated as much as the thickness step As a result, a problem of causing air bubbles may occur.

The base layer may have a transmittance of 60 to 90%, or 75 to 95% for visible light having a wavelength of 400 to 700 nm. If the transmittance of the base layer with respect to visible light is less than the above range, there may be a problem in that it cannot be applied to automobile glass in which the driver's visible light must be secured.

thermal coating layer

The heating coating layer is heated by electric current and serves to remove the frost on the glass surface. The heat-generating coating layer for removing the frost from the glass surface is required to have excellent heat-generating properties and high flexibility at the same time. In addition, since automobile glass has a double-curve shape in which horizontal and vertical curvatures are formed, it is necessary that the heating coating layer is not restricted by shape and shape. Indium oxide (ITO) heating element, which is widely used as an existing transparent conductor, is difficult to use as a heating layer because it lacks flexibility due to the characteristic of oxide. there was. Accordingly, the present invention solves the above-described problems by applying the nanowires in the heating coating layer.

The nanowire used in the heating coating layer is a material having a linear structure having a diameter of nanometers (nm) in atoms. The heating coating layer of the heating film of the present invention has excellent conductivity by forming a three-dimensional conductive network by forming nanowires in contact with each other.

The heating coating layer may include nanowires having an average length of 10 to 40 nm or 25 to 35 nm. When the average length of the nanowires in the heating coating layer is less than the above range, it is difficult to form a network between the nanowires, and thus the conductivity is weak or disappears. In addition, when the average length of the nanowires exceeds the above range, the nanowire-shaped particles are each entangled like a skein of yarn, and uniform conductivity of the coated heating coating layer is formed, that is, uniform temperature heating is realized due to difficulties in manufacturing the heating coating layer or in the coating process. It becomes difficult, and there is a problem in that local overheating occurs when the heating coating layer prepared in this way is applied.

The nanowire may include a metal having excellent conductivity, for example, one or more metals selected from the group consisting of silver, gold, platinum, aluminum, and copper. Specifically, the nanowire may include silver (Ag), and more specifically, may include silver (Ag).

In addition, the heating coating layer may be prepared by spray coating, dip coating, or spin coating a coating layer composition including nanowires.

The heating coating layer may have a resistance of 5 to 25 Ω/□, or 8 to 20 Ω/□. When the resistance of the heating coating layer is less than the above range, film tearing due to overheating occurs, and when the resistance of the heating coating layer is above the above range, there may be a problem in that the defrosting effect is insufficient due to deterioration of the heating performance.

In addition, the heating coating layer may have an average thickness of 50 to 300 nm, or 150 to 200 nm. When the average thickness of the exothermic coating layer is less than the above range, the heat generating performance is insufficient, the defrosting effect is insufficient, the scratch strength is lowered, and when the average thickness of the exothermic coating layer is less than the above range, the hardness of the exothermic coating layer is insufficient and breakage may occur. .

The glass laminate may further include an adhesive layer, and specifically, a first glass plate, a first adhesive layer, a copper thin film, a second adhesive layer, a heating film, a third adhesive layer, and a second glass plate are sequentially laminated It may include a form that has been

Referring to FIG. 3 , the glass laminate according to the present invention includes a first glass plate 100 , a first adhesive layer 510 , copper thin films 210 and 220 , a second adhesive layer 520 , and a heating film 300 . , the third adhesive layer 530 and the second glass plate 400) may include a laminated form in order.

adhesive layer

Any material that has adhesive strength and becomes transparent after bonding may be used for the adhesive layer. For example, the adhesive layer may include polyvinylbutyral (PVB), ethylene vinyl acetate (EVA), polyurethane (PU), or the like.

The average thickness of the adhesive layer may be appropriately adjusted.

The glass laminate may be applied for defrosting in the wiper area of the windshield of an automobile. Referring to FIG. 1 , the glass laminate may be applied to a wiper area of a windshield of a vehicle and connected to a voltage applying device 10 .

In addition, the glass laminate may further include a pigment layer between the first glass plate and the copper thin film. Specifically, the glass laminate may further include a pigment layer between the first glass plate and the first adhesive layer.

In this case, the pigment layer may include a pigment that can be conventionally used for glass, for example, enamel or the like.

The glass laminate according to the present invention as described above has a simple manufacturing process and less waste of raw materials, so manufacturing costs can be reduced, and the problem of disconnection and defrost removal is a long time because it does not use a thin metal wire. By preventing problems, even frost on a large area can be removed in a short time.

Hereinafter, the present invention will be described in more detail through examples. However, these examples are only for helping the understanding of the present invention, and the scope of the present invention is not limited to these examples in any sense.

[Example]

Example 1. Preparation of Glass Laminate

A pigment layer is formed by coating enamel with an average thickness of 10 μm on the first glass plate (soda-lime glass, average thickness: 2.1 mm), and polyvinyl butyral (PVB, manufacturer: sekisui, product name: S-) on the pigment layer LEC) to form a first adhesive layer having an average thickness of 0.38 mm, and laminated two copper thin films having a thickness of 0.08 mm on the first adhesive layer at an interval of 120 mm. Thereafter, a second adhesive layer having an average thickness of 0.03 mm was formed with a methacrylate polymer on the copper thin film, and a heating film was laminated on the second adhesive layer. Thereafter, a third adhesive layer having an average thickness of 0.38 mm was formed on the heating film with polyvinyl butyral (PVB, manufacturer: sekisui, product name: S-LEC), and a second glass plate (soda lime glass, average thickness: 1.6 mm) to prepare a glass laminate. The heating film has a length of 920 mm and a width (H) of 140 mm, the upper copper thin film has a length (L) of 920 mm and a width (C) of 10 mm, and the lower copper thin film has a length (L′) of 920 nm and a width (C) ) was 10 mm.

At this time, the heating film was prepared by forming a heating coating layer having a thickness of 200 nm by forming a coating layer composition on a base layer having a thickness of 0.08 mm made of polyethylene terephthalate (PET, manufacturer: SK Chemicals, product name: Skyroll v7610). As the coating layer composition, an aqueous solution in which silver nanowires having an average length of 12 nm were dispersed at a concentration of 1.2 wt% was used. The base layer had a transmittance of 85% with respect to light having a wavelength of 550 nm, and the heat-generating coating layer had a resistance of 8Ω/□.

Examples 2 to 9 and Comparative Examples 1 to 6.

Glass in the same manner as in Example 1, except that the length and width of the copper thin film, the thickness of the base layer (PET layer), the length of the silver nanowire in the heating coating layer, and the thickness of the heating coating layer were adjusted as shown in Table 1. A laminate was prepared.

Length of the upper copper thin film
(mm)(L) Length of the lower copper thin film
(mm)(L') Interval between copper thin films (mm) (D) L/D thermal coating layer resistance
(Ω/□) Length of silver nanowire (nm) thickness
(nm) Example 1 920 920 120 7.7 8 12 200 Example 2 920 920 105 8.9 8 12 200 Example 3 920 920 180 5.1 8 12 200 Example 4 920 920 120 7.7 8 15 200 Example 5 920 920 120 7.7 8 20 200 Example 6 920 920 120 7.7 8 30 200 Example 7 920 920 120 7.7 8 40 200 Example 8 920 920 120 7.7 8 12 100 Example 9 920 920 120 7.7 8 12 300 Comparative Example 1 920 920 190 4.8 8 12 200 Comparative Example 2 920 920 100 9.2 8 12 200 Comparative Example 3 920 920 120 7.7 8 8 200 Comparative Example 4 920 920 120 7.7 8 45 200 Comparative Example 5 920 920 120 7.7 8 12 40 Comparative Example 6 920 920 120 7.7 8 12 500

Comparative Example 7.

A glass laminate was prepared in the same manner as in Example 1, except that silver paste (manufacturer: Nano New Material) was used instead of the copper thin film. At this time, the resistance of the heating coating layer was 20Ω/□.

Test Example: Evaluation of the thermal performance of a glass laminate

The heating performance of the glass laminates prepared in Examples and Comparative Examples was measured in the following manner, and the results are shown in Table 2 and FIG. 4 .

Specifically, water was sprayed on the glass laminate and left to stand at -30°C below zero to form frost. After applying a voltage of 13.5V and a current of 10.88A for 20 minutes, the maximum temperature of the glass laminate was measured. At this time, the temperature of the glass laminate was measured with a thermal imaging camera (FLIR T620), and the temperature measurement result of the glass laminate of Example 1 according to the current application time is shown in FIG. 4 .

Maximum temperature (℃) Example 1 68.3 Example 2 69.5 Example 3 65.1 Example 4 65.9 Example 5 66.8 Example 6 68.5 Example 7 69.7 Example 8 65.3 Example 9 69.8 Comparative Example 1 50.1 Comparative Example 2 72.5 Comparative Example 3 25.8 Comparative Example 4 82.0 Comparative Example 5 32.8 Comparative Example 6 130.5 Comparative Example 7 X

As shown in Table 2, the glass laminates of Examples were suitable for defrosting because the maximum temperature was appropriate at 65°C to 70°C.

On the other hand, in Comparative Example 1, the amount of heat generated was insufficient because the distance between the copper thin films was narrow compared to the length of the copper thin film.

In addition, in Comparative Example 3, the length of the nanowire was insufficient, and thus the amount of heat generated was insufficient, and in Comparative Example 4, it was confirmed that the nanowire was excessively heated because the length of the nanowire was long.

In Comparative Example 5, the heating value was insufficient because the thickness of the heating coating layer was insufficient, and in Comparative Example 6, it was confirmed that excessive heat was generated because the thickness of the heating coating layer was excessively thick.

In addition, in Comparative Example 7 using the silver paste, the temperature was excessively increased and the film was damaged, so that the temperature measurement was impossible.

Claims (4)

Including a form in which the first glass plate, the copper thin film, the heating film and the second glass plate are sequentially laminated,
The heating film includes a substrate layer and a heating coating layer laminated on one surface of the substrate layer,
The exothermic coating layer includes nanowires having an average length of 10 to 40 nm and an average thickness of 50 to 300 nm,
The copper thin film is a glass laminate that conducts an electric current from a voltage application device. The method according to claim 1,
The base layer has an average thickness of 50 to 500 μm, and a transmittance of 60 to 90% for visible light having a wavelength of 400 to 700 nm, a glass laminate. The method according to claim 1,
The copper thin film includes an upper copper thin film and a lower copper thin film disposed to be spaced apart,
The length of the upper copper thin film and the average distance between the upper copper thin film and the lower copper thin film is 5 to 9: 1, a glass laminate. The method according to claim 1,
A glass laminate comprising a form in which a first glass plate, a first adhesive layer, a copper thin film, a second adhesive layer, a heating film, a third adhesive layer, and a second glass plate are sequentially laminated.

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