JPH05343723A - Sealing method for planar element - Google Patents

Abstract

PURPOSE:Not to deteriorate an element due to a heat at adhering when a metallic foil is adhered to a substrate with thermoplastic resin to protect the element formed in a center of the substrate from an outside. CONSTITUTION:A metallic foil 3 in the peripheral part of a substrate where an element is not formed is instantly heated and simultaneously pressurized by using a high frequency induction heat by coils having a specific shape, and thermoplastic resin 12 is melted between the substrate in the peripheral part and the metallic foil 3 and is gradually cooled to stiffen resin, whereby the element is sealed from an outside without heat-deteriorating the element in a center of the substrate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device such as a solar cell or the like formed in a plane on a support substrate, and a circuit formed on a support substrate such as a hot carpet in a plane form, which is hermetically sealed from outside. It is related to the technology.

[0002]

2. Description of the Related Art In recent years, with the rapid spread of the use of solar cells, it is desired to improve the performance of the solar cells and reduce the cost.

Conventionally, as a method for producing a low-cost solar cell, a solar cell element is formed by placing an aluminum foil having a backside of a thermoplastic resin adhered on the solar cell element formed on a glass substrate. There is a method in which only the peripheral part of the glass substrate is thermocompression-bonded with a heating body, the thermoplastic resin is melted, and then the resin is cured by slow cooling to bond the peripheral part of the glass substrate to the aluminum foil (special feature). (Kaisho 63-179).

A conventional device for sealing a planar element such as a solar cell element will be described below with reference to the drawings. FIG. 5 shows an example of a conventional planar element sealing device. In the figure, 10 is a solar cell element, 6 is a glass substrate formed on a glass substrate, 3 is a back surface protective film made of aluminum foil, and 1 is a back surface protective film.
Reference numeral 2 is an insulating resin layer made of a thermoplastic resin. Reference numeral 14 is a heating body which incorporates a sheath heater 15, and 16 is a pressurizing body, which is attached in close contact with the heating body 14.

FIG. 6 is a top view of the pressing body 16, and in order to prevent the solar cell element 10 from being deteriorated by being directly heated and pressed, the peripheral portion of the glass substrate 6 on which the solar cell element 10 is not formed. Only the heat and pressure is applied.

When the solar cell element is sealed, the heating element 14 is heated by 15 sheath heaters, and this heat 17
To the metal foil 3 on the insulating resin layer 12 by the air cylinder 18 to melt the insulating resin layer 12 in the peripheral margin 11 of the glass substrate 6. After that, the pressure body 17 is raised by an air cylinder 18 and the insulating resin layer 12 is gradually cooled to be cured, and the metal foil 3 and the glass substrate 6 are adhered to each other to seal the solar cell element 10. To do.

[0007]

However, in the above-mentioned sealing device, since the glass substrate has a large heat capacity, it takes a long time to melt the insulating resin layer. Therefore, the solar cell element in the center of the substrate also needs to be melted. The heat may be transferred and the performance of the solar cell element may be degraded. Also, due to the heat capacity of the pressurizing body itself, there is a large energy loss to keep the heating body at a certain temperature or more at all times, and further, when the lead wire is pulled out from the solar cell element to the outside of the glass substrate, There has been a problem that the shape of the pressing body has to be changed according to the shape such as the thickness.

[0008]

In order to solve the above-mentioned problems, the present invention is to seal a planar element formed at the center of a supporting substrate with a metal foil, and to seal it between the supporting substrate and the metal foil. A thin film of thermoplastic resin is placed, and by heating the metal foil only on the peripheral part of the supporting substrate by high-frequency induction heating, the thin film of the thermoplastic resin corresponding to this part is melted and then slowly cooled and cured. By doing so, the supporting substrate and the metal foil are bonded to each other.

[0009]

As described above, according to the present invention, it is not necessary to take into consideration the heat capacity of the glass substrate or the pressurizing body because only an arbitrary portion of the metal foil, which is the surface to be heated, is instantaneously heated. Since the metal foil in the peripheral portion of the glass substrate is heated only at the moment when the power is turned on, the influence of heat transfer to the solar cell element in the center of the substrate can be reduced.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

The principle of the high frequency induction heating method used in the present invention is shown in FIG. When a high frequency current is supplied to the heating coil winding 1, a magnetic flux 2 is generated around the winding 1, an eddy current 4 is generated in a metal foil 3 on the winding, and the metal foil 3 is heated by Joule heat thereof. .. In order to locally and instantly raise the temperature of the metal foil, it suffices to dispose the heating coil winding only just below the target portion and pass a large high-frequency current.

FIG. 2 shows a heating winding shape for instantly raising the temperature of the metal foil at the peripheral portion and the corner portion of the glass substrate used in the present invention. In order to instantaneously heat only the metal foil 3 in the peripheral portion of the glass substrate 6, the number of turns of the winding 1 is increased in the vertical direction of the metal foil 3 and the magnetic flux 2 is increased, so that a large eddy current 4 is generated only in the peripheral portion. At the corners of the glass substrate 6, the winding 1 is formed into a small loop shape, and a ferrite core, which is a ferromagnetic material, is inserted into the smaller loop to further increase the magnetic flux 2 and to increase the eddy current. Increased by 4.

FIG. 3 is a top view of a heating jig for high frequency induction heating for sealing a solar cell element formed at the center of a glass substrate, which is used in the embodiment of the present invention. 1 in the figure
Is a heating coil winding, and in the present invention, a litz wire made of a thin element wire is used, and is wound plural times in the vertical direction with respect to FIG. At the four corners of the glass substrate and at the portion where the lead wire was pulled out from the solar cell element, the litz wire was wound into a loop, and the ferrite core 7 was inserted inside the loop. Reference numeral 8 denotes a resin thick plate for fixing the heating coil winding.

FIG. 4 is a schematic side view of an apparatus for sealing a solar cell element formed at the center of a glass substrate using the heating jig. In the figure, 9 is the heating jig shown in FIG. 3, in which cooling water is flowing. 10 is a solar cell element,
6 is a glass substrate, 11 is a peripheral margin of the glass substrate, 12
Is a thermoplastic insulating resin layer, 3 is a back surface protective film of a metal foil made of aluminum, 13 is a pressure device, and 5 is a high frequency power source.

To seal the solar cell element formed in the center on the glass substrate using the sealing device of FIG. 4, first, apply a pressure of 4 kg / cm ² or more with the pressure device of 13. hand,
The glass substrate 6, the insulating resin layer 12, and the back surface protective film 3 of the metal foil are stacked and pressure-bonded to the heating jig 9, and then the high frequency power source 5 is operated to heat the metal foil 3 by the heating jig 9 to form the glass substrate. 6, a thermoplastic insulating resin layer 12 immediately below the peripheral margin portion 11
And then the high frequency power source 5 is stopped, the insulating resin layer 12 is cured by the cooling water flowing in the heating jig 9, and then the pressure device is stopped to seal the solar cell element. Took out.

[0016]

As described above, according to the present invention, when the planar element formed at the center of the supporting substrate is sealed with the metal foil, the thin film of the thermoplastic resin is placed between the supporting substrate and the metal foil. By heating the metal foil only on the peripheral portion of the supporting substrate by high frequency induction heating, the thin film of the thermoplastic resin is melted, and then gradually cooled to be cured, whereby the supporting substrate and the metal foil are separated from each other. By bonding,
Since the metal foil can be heated directly, it is not necessary to consider the heat capacity of the supporting substrate, and it is possible to seal in a short time and with a small amount of heat. Also, the number of turns of the heating coil winding around the supporting substrate is perpendicular to the supporting substrate. By increasing the number of elements, the temperature of the metal foil in the peripheral portion of the substrate can be raised faster, and heat transfer to the element portion inside the support substrate can be suppressed, so that the element is less deteriorated. Furthermore, when a large amount of heat is required locally, such as at the four corners of the support substrate and the lead-out portion to the outside, the heating coil winding immediately below that portion is made into a small loop shape, and this small loop The heating capacity can be easily improved by inserting a cylindrical ferrite core therein.

[Brief description of drawings]

FIG. 1 is a principle diagram of a high frequency induction heating method used in the present invention.

FIG. 2 is a conceptual diagram when locally heating the periphery of the substrate, which is the sealing of the planar element of the present invention, and the corners by the high frequency induction heating method.

FIG. 3 is a top view of the high frequency induction heating jig of the planar element sealing device used in the present invention.

FIG. 4 is a schematic side view showing an example of a planar element sealing device used in the present invention.

FIG. 5 is a schematic side view showing an example of a conventional planar element sealing device.

FIG. 6 is a top view of the pressure body.

[Explanation of symbols]

 3 Metal foil 5 High frequency power supply 6 Glass substrate 9 Heating jig 10 Solar cell element 11 Peripheral margin on glass substrate 12 Insulating resin layer 13 Pressurizing device

Claims (7)

[Claims] 1. When a planar element formed in the center of a supporting substrate is sealed with a metal foil, a thin film of a thermoplastic resin is placed between the supporting substrate and the metal foil, and this is subjected to high frequency induction heating. The support substrate and the metal foil are bonded to each other by heating the metal foil only in the peripheral portion of the support substrate to melt the thin film of the thermoplastic resin, and then gradually cooling the resin to cure the resin. And a method for sealing a planar element. 2. The method for sealing a planar element according to claim 1, wherein the winding shape of the heating coil used for the high frequency induction heating is a shape along the outer shape of the support substrate. 3. The method for encapsulating a planar element according to claim 1, wherein windings of a heating coil used for high frequency induction heating are stacked in multiple layers by increasing the number of turns in a direction perpendicular to the metal foil. 4. The method for sealing a planar element according to claim 1, wherein the heating coil winding used for high frequency heating has a small loop formed in a part thereof. 5. The method of encapsulating a planar element according to claim 1, wherein the support substrate is polygonal, and the heating coil winding forms a small loop at a corner portion of the support substrate. 6. The plane according to claim 1, wherein the winding shape of the heating coil used for high-frequency induction heating forms a small loop in the peripheral portion on the support substrate corresponding to the portion where the terminals of the planar element are drawn out. Method for sealing element. 7. The method of sealing a planar element according to claim 4, wherein the small loop is wound around a ferrite core.