TW201505195A - Back-contact solar battery module - Google Patents

Abstract

This back-contact solar battery module has a transparent substrate, a transparent sealing material, a solar battery cell, a sealing material, and a circuit-attached back sheet layered in the stated order. The circuit-attached back sheet is formed from a laminated body in which the following are layered: a color insulating layer compounded with a UV-cutting colorant; circuits made of a patterned metal layer, and wiring for connecting the circuits to each other; and the back sheet. The color insulating layer is formed in a non-wiring section on the outer peripheral edge of the circuit-attached back sheet.

Description

Rear contact type solar cell module

The present invention relates to a rear contact type solar cell module. In particular, it relates to a backlight sheet constituting an attached circuit of a solar cell module.

The present application claims priority based on Japanese Patent Application No. 2013-106987, filed on May 21, 2013 in Japan, and Japanese Patent Application No. 2013-123733, filed on Jun. Use its content.

In recent years, the spread of solar power generation using natural energy power generation systems is rapidly progressing. The solar cell module for solar power generation is disposed adjacent to a plurality of solar cells, and electrically connected to each solar cell unit to take out electric power. When the wiring of the solar cell units electrically connected to each other is exposed to the light receiving surface side, the light receiving area is reduced. Therefore, a post-contact type connection structure is adopted in which a connection electrode is formed on the surface opposite to the light-receiving surface of the solar cell, and the connection material is interposed and connected to the circuit piece for wiring the connection electrode. As the connecting material, for example, solder or silver paste or the like is used. The circuit piece for the contact type solar cell module is used to prevent the movement of the connecting material while the connecting material does not enter the adjacent circuit, and at the same time, the insulating layer between the insulating circuits is provided. .

For example, an example of the layer structure of the general after-contact solar cell module 170 is shown in FIGS. 5A to 5E. 5A is a transparent substrate 11 , a transparent encapsulant 12 , a solar cell unit (rear contact unit) 13 , a package material 14 , an insulating layer 110 , a circuit sheet 15 , and a backlight sheet which are sequentially laminated from the light receiving side (surface). The layer structure of the solar cell module 170 of 16. The connection electrode 18 of the back surface of the solar cell unit 13 and the circuit 120 patterned with the metal layer are electrically connected by an adhesive or a silver paste of the connecting material 19 to extract electric power. In the circuit sheet 15, the metal layer and the sheet substrate are bonded to each other with the adhesive layer 112 interposed therebetween, and the metal layer is patterned to form the wiring portion 121 between the connection circuit 120 and the circuit. Further, on the back surface of the circuit board 15, the backlight layer 16 is laminated with the adhesive layer 112 interposed therebetween.

Further, in the fifth drawing, the transparent substrate 21, the transparent package 22, the solar cell unit (back contact unit) 23, the package member 24, the electrically insulating layer 29, and the circuit sheet 25 are sequentially laminated from the light receiving side (surface). The module of the backlight sheet 26 is electrically connected to the connection electrode 27 on the back surface of the solar cell unit 23 by an adhesive or silver paste of the connection material 28, and the circuit 211 patterned by the metal layer. The circuit board 25 is formed by bonding the metal layer and the sheet substrate 214 with the adhesive 221 interposed therebetween, and patterning the metal layer to form the circuit 211. Further, on the back surface of the circuit board 25, the backlight layer 26 is laminated with the adhesive layer 221 interposed therebetween.

Recently, research and development is being carried out to reduce the production cost of the above-mentioned type of solar cell module. For example, as shown in FIG. 5B, a circuit-backed backlight sheet 17 has been developed which integrates the circuit board 15 with the backlight sheet 16. For example, a circuit-backed backlight sheet 17 has been developed which is a polyethylene terephthalate film or polyethylene naphthalate as the backlight sheet 16. On the film, a metal layer such as a copper foil or an aluminum foil is bonded to the intermediate layer, and the metal layer is patterned to form a wiring portion 121 between the circuit 120 and the connection circuit. The insulating layer 110 is formed by removing a portion where the connecting member 19 connects the connection electrode 18 and the circuit 120. Fig. 5C shows a rear contact type solar cell module 180 reinforced by an aluminum frame 124. In order to take out the generated electric power, the plurality of connected solar battery cells 13 are connected to the terminal box 123 outside the solar battery module 180 by connecting the wires 122. The insulating layer 110 is formed by removing a portion where the connecting member 19 connects the connection electrode 18 and the circuit 120.

Further, for example, as shown in FIG. 5E, a circuit-backed backlight sheet 212 in which the circuit board 25 and the backlight sheet 26 are integrated has been developed. For example, a circuit-backed backlight sheet 212 has been developed which is formed on a polyethylene terephthalate film or a polyethylene naphthalate film as the backlight sheet 26 with the adhesive layer 221 interposed therebetween to make copper A metal layer such as a foil or an aluminum foil is bonded to each other to pattern the metal layer to form a circuit 211.

The insulating layers 29 and 110 are formed of a material of a so-called solder resistor, and since the material is expensive, it is a main cause of high production cost of the solar cell module. It is desirable to use as little material as possible. Further, in the formation of the insulating layer, it is necessary to thermally harden or to cure by ultraviolet rays after printing. In particular, thermal hardening typically takes 10 to 60 minutes at 100 to 160 °C. In general, in order to form a thickness of 20 to 30 μm, a method of forming by screen printing and hardening it by heat treatment or ultraviolet irradiation is employed. Since the insulating layer is expensive, the productivity of screen printing is low, and the production cost is high, it has been developed to reduce the amount of solder resist or to omit the solder resist to make the package materials 14, 24 have an insulating function.

Further, since the solder resist is colored, it absorbs ultraviolet rays by the solder resist to prevent embrittlement of the backlight sheet, for example, a polyethylene terephthalate film. Therefore, although the solder resist is omitted and the package material has an insulating function, the production cost can be reduced, and conversely, the problem of embrittlement of the polyethylene terephthalate film occurs.

It is also considered to incorporate a UV-filtering coloring agent in the packaging materials 14, 24, such as a black pigment such as carbon black, a white pigment such as titanium oxide or barium sulfate, but the pigments may be in a packaging material such as ethylene-acetic acid. When the vinyl ester copolymer (EVA) resin moves (migrates), it moves to the transparent sealing material on the light-receiving surface side, thereby hindering light reception and lowering power generation efficiency.

Further, the backlight sheet must have excellent mechanical properties and have various properties such as weather resistance, heat resistance, moisture resistance, and hydrolysis resistance. As such a backlight sheet, it is desirable to have weather resistance for outdoor exposure which can withstand long-term use, that is, durability (about 20 years), and a fluorine-based resin film or a polyethylene terephthalate having weather resistance can be cited. Ester film and the like.

However, although the fluorine-based resin film has weather resistance, there is a problem that the material cost is high. On the other hand, although the price of the polyethylene terephthalate film is relatively low, heat resistance or weather resistance is not sufficient. In particular, the requirement for improving weather resistance is increased.

There is a proposal to impart weather resistance to a polyethylene terephthalate film. For example, there is a proposal to contain an ultraviolet absorber in a polyethylene terephthalate film (Patent Document 1); a proposal to reduce ultraviolet transmittance by using a white polyethylene terephthalate film containing titanium dioxide (patent) Document 2); a proposal to provide a water vapor barrier layer on the surface of a polyethylene terephthalate film containing a UV absorber (Patent Document 3).

However, the ultraviolet absorber containing the polyethylene terephthalate film has a problem that the production cost is high and the adhesion to the metal layer is lowered. Further, the polyethylene terephthalate film containing titanium dioxide also has a problem of high production cost. Further, in the case where a water vapor barrier layer is provided on the surface of the film containing the ultraviolet absorber, there is a concern that the adhesion to the water vapor barrier layer is lowered by the migration of the ultraviolet absorber.

From the above, a rear contact type solar cell module is desired which reduces the production cost and the backlight sheet does not become brittle.

Prior technical literature Patent literature

Patent Document 1 Japanese Patent Laid-Open Publication No. 2009-188105

Patent Document 2 Japanese Patent Laid-Open Publication No. 2006-270025

Patent Document 3 Japanese Patent Laid-Open Publication No. 2006-261189

The present invention has been made in an effort to solve the above problems, and an object of the invention is to provide a rear contact type solar cell module which reduces the material used in the insulating layer, reduces the production cost, and does not embrittle the backlight.

Further, an object of the present invention is to provide a rear contact type solar cell module which is industrially omitted in the structure in which the solder resist is omitted, and the backlight sheet is not embrittled.

A back contact type solar cell module according to a first aspect of the present invention includes a transparent substrate and a transparent sealing material which are sequentially laminated. a solar cell unit, a sealing material, and a backlight sheet with a circuit; the backlight of the circuit is a circuit formed by laminating a colored insulating layer and a patterned metal layer which have been blended with a UV-filtering pigment; The wiring portion between the circuits and the laminate of the backlight sheet are formed; and the colored insulating layer is formed on the non-wiring portion of the peripheral edge of the backlight of the circuit.

In the contact type solar cell module after the first aspect of the present invention, a black pigment containing carbon black or titanium black has been blended in the colored insulating layer, the black being relative to the weight of the colored insulating layer The blending ratio of the pigment may also be from 1 to 4% by weight.

In the contact type solar cell module after the first aspect of the present invention, a white pigment containing titanium oxide or barium sulfate has been blended in the colored insulating layer, the white color relative to the weight of the colored insulating layer The blending ratio of the pigment may also be 5 to 15% by weight.

In the contact type solar cell module after the first aspect of the invention, the backlight sheet may also be formed of a polyethylene terephthalate film.

A rear contact type solar cell module according to a second aspect of the present invention includes a transparent substrate, a transparent sealing material, a solar cell unit, a sealing material, and a backlight sheet with a circuit laminated in sequence; the attached circuit The backlight sheet is formed of a colored adhesive layer in which a metal layer, a pigment having ultraviolet ray-removing pigment has been laminated, and a backlight sheet; and the metal layer is patterned to form an electric circuit.

In the contact type solar cell module after the second aspect of the present invention, a black pigment containing carbon black or titanium black has been blended in the colored adhesive layer, the black color relative to the weight of the colored adhesive layer The blending ratio of the pigment may also be from 1 to 4% by weight.

In the contact type solar cell module after the second aspect of the present invention, a white pigment containing titanium oxide or barium sulfate has been blended in the colored adhesive layer, the white color relative to the weight of the colored adhesive layer The blending ratio of the pigment may also be 5 to 15% by weight.

In the contact type solar cell module after the second aspect of the present invention, the backlight sheet may also be formed of a polyethylene terephthalate film.

According to the contact type solar cell module of the first aspect of the present invention, since the colored insulating layer of the backlight sheet with the circuit is formed on the non-wiring portion at the peripheral edge of the backlight sheet, the backlight sheet can be prevented from being embrittled by the ultraviolet ray. Further, since the insulating resin used for the insulating layer can be reduced, the production cost can be reduced.

According to the first aspect of the present invention, the backlight of the circuit is formed by a circuit in which a colored insulating layer having a pigment having ultraviolet ray-removing pigment, a patterned metal layer, and a wiring portion connecting the circuits are laminated. The laminated body is formed of a laminate of the backlight sheet, and the colored insulating layer is formed of a non-wiring portion on the peripheral edge of the backlight sheet, and the non-wiring portion of the peripheral edge of the backlight sheet can be prevented from being embrittled. In the wiring portion connecting the circuit or the circuit on the backlight sheet, since the metal layer is provided, ultraviolet rays are removed, and embrittlement of the backlight sheet does not occur, and the backlight sheet can be prevented by forming a colored insulating layer on the non-wiring portion of the peripheral edge. Embossed.

Further, since the colored insulating layer is formed only on the non-wiring portion on the peripheral edge of the backlight sheet, the insulating resin used for the insulating layer can be reduced, so that the production cost can be reduced.

Further, according to the first aspect of the present invention, the colored insulating layer has been blended with a black pigment containing carbon black or titanium black, and the blending ratio of the black pigment is 1 to the weight of the colored insulating layer. 4% by weight, it can absorb ultraviolet rays efficiently and filter it out.

Further, according to the first aspect of the present invention, the colored insulating layer has been blended with a white pigment containing titanium oxide or barium sulfate, and the blending ratio of the white pigment is 5 to 5 by weight with respect to the weight of the colored insulating layer. 15% by weight, the ultraviolet rays can be efficiently reflected and filtered.

Further, according to the first aspect of the present invention, since the backlight sheet is made of polyethylene terephthalate, it is a relatively inexpensive material, and the production cost can be reduced.

According to the second aspect of the present invention, since the backlight sheet with the circuit is composed of a laminated body in which a metal layer, a colored adhesive layer having a pigment having ultraviolet absorbing property and a backlight sheet are laminated, the metal layer is patterned. At the same time as the formation of the circuit, a colored adhesive layer is also laminated on the backlight sheet to prevent embrittlement of the backlight sheet.

According to the second aspect of the present invention, a layered body in which a metal layer is laminated and a pigmented back layer having a pigment having ultraviolet absorbing property is mixed with a backlight sheet is formed, and the metal layer is patterned to form an electric circuit. In the formed backlight of the circuit, since the colored adhesive layer is laminated on the backlight, it is possible to impart weather resistance to the backlight and prevent embrittlement.

The pigment having ultraviolet ray absorbing property contained in the colored back layer does not move to the package material, and does not adversely affect the adhesion to the package material.

According to a second aspect of the present invention, the colored adhesive layer is blended with a black pigment comprising carbon black or titanium black, and the black pigment blending ratio is 1 to 4 by weight with respect to the weight of the colored adhesive layer. %, can absorb ultraviolet rays efficiently and filter out.

According to a second aspect of the present invention, the colored adhesive layer is blended with a white pigment comprising titanium oxide or barium sulfate, and the blending ratio of the white pigment is 5 to 15 by weight with respect to the weight of the colored adhesive layer. %, which can reflect the ultraviolet light efficiently and filter it out.

According to the second aspect of the present invention, the backlight sheet is made of polyethylene terephthalate, which is a relatively inexpensive material, and can reduce the productivity cost due to mechanical strength, heat resistance and the like.

1A‧‧‧UV

11, 21‧‧‧ transparent substrate

12, 22‧‧‧ Transparent packaging materials

13, 23‧‧‧ solar battery unit

14, 24‧‧‧Package

15, 25‧‧‧ circuit pieces

16, 26‧‧‧ backlight film

17, 212‧‧‧ Backlit film with circuit

18, 27‧‧‧ connection electrode

19, 28‧‧‧Connecting materials

110, 29‧‧‧Insulation (electrical insulation)

111‧‧‧Colored insulation

210‧‧‧Coloring layer

112‧‧‧Next layer

120, 211‧‧‧ circuits

121‧‧‧Wiring Department

122‧‧‧Wire

123‧‧‧Terminal box

124‧‧‧Aluminum frame

130, 213‧‧‧ pigments

140‧‧‧ peripheral edge

141‧‧‧ Non-wiring department

214‧‧‧Sheet substrate

220‧‧‧metal layer

221‧‧‧Next layer

222‧‧‧Layer

150, 230‧‧‧ contact solar cell module after the invention

160‧‧‧Contact solar cell module (with aluminum frame) after the present invention

170, 240‧‧‧General contact solar battery modules

180‧‧‧General contact solar cell module (with aluminum frame)

Fig. 1A is an explanatory view showing an example of a layer structure of a contact type solar cell module according to the first embodiment of the present invention.

Fig. 1B is an explanatory view showing an example of a layer structure of a contact type solar cell module according to the first embodiment of the present invention.

Fig. 2 is an explanatory view showing an example of a layer structure of a peripheral edge portion of a backlight sheet with a circuit according to the first embodiment of the present invention.

Fig. 3 is an explanatory view showing an example of a layer structure of a contact type solar cell module according to a second embodiment of the present invention.

Fig. 4A is an explanatory view showing an example of a layer structure of a contact type solar cell module according to the second embodiment of the present invention.

Fig. 4B is an explanatory view showing an example of a layer structure of the contact type solar cell module of the present invention.

Fig. 5A is an explanatory view showing an example of a layer structure of a general solar battery module.

Fig. 5B is an explanatory view showing an example of a layer structure of a general solar battery module.

Fig. 5C is an explanatory view showing an example of a layer structure of a general solar battery module.

Fig. 5D is an explanatory view showing an example of a layer structure of a general solar battery module.

Fig. 5E is an explanatory view showing an example of a layer structure of a general solar battery module.

[Formation of the Invention]

Hereinafter, a first embodiment of the present invention will be described.

(First embodiment)

1A and 1B are explanatory views showing an example of a layer structure of a contact type solar cell module according to the first embodiment of the present invention. Fig. 1A is an explanatory view showing an example of a layer structure of the solar battery module 150. The solar cell module 150 is formed of a transparent substrate 11 such as a front glass, a transparent encapsulant 12, a solar cell unit 13, a package material 14, and a backlight 17 with an electrical circuit. The connection electrode 18 of the electron extraction electrode is provided on the back surface of the solar cell unit 13, and the connection material 19 to which the circuit 120 and the connection electrode 18 are connected is formed. The solar battery cells 13 are formed in plural numbers, and the respective circuits 120 are connected by the wiring portion 121.

The connecting material 19 is generally made of a conductive material such as solder or silver paste. The backlight sheet 17 with the circuit is made by interposing the layer 112 in the middle. The laminated metal layer and the laminated body of the backlight sheet 16 are formed, and the metal layer is patterned to form the wiring portion 121 between the connection circuit 120 and the circuit. Further, in addition to the position where the connection electrode 18 is connected to the circuit 120 by the connecting member 19, the sealing material 14 is also interposed and insulated. Further, the transparent encapsulant 12 is also interposed between the transparent substrate 11 and the solar cell unit 13.

In the solar battery module, in the portion where the metal layer such as the wiring portion 121 between the solar battery unit 13 or the circuit 120 and the connection circuit is formed, the ultraviolet ray 1A is easily reflected by the metal layer, and the backlight sheet is less likely to be embrittled. However, in the non-wire portion 141 of the peripheral edge 140 of the backlight sheet, that is, the portion where the metal layer is not formed, embrittlement of the backlight sheet 16 irradiated with the ultraviolet ray 1A is likely to occur. Therefore, by forming the colored insulating layer 111 only on the non-wiring portion 141 of the peripheral edge 140 of the backlight sheet, that is, the portion where the metal layer is not formed, the portion can be prevented from being embrittled, and the entire backlight sheet 16 can be prevented from being embrittled. .

Fig. 1B shows an example of the contact type solar cell module 160 after the state in which the aluminum frame is reinforced. An example of a state in which an aluminum frame 124 treated with an alumite is used to reinforce a solar cell module is shown. The electric power generated is connected to the terminal box 123 on the outer side of the backlight sheet 16 by the wire 122.

For example, in the wiring portion 121 between the circuit 120 or the wiring circuit, the ultraviolet rays 1A are filtered by the metal layer. On the other hand, the non-wiring portion 141 of the peripheral edge 140 of the backlight sheet, that is, the non-wiring portion 141 between the aluminum frame 124 and the wiring portion 121 or the circuit 120 is irradiated with the ultraviolet ray A. Therefore, by forming the colored insulating layer 111 only in the non-wiring portion 141, embrittlement of the backlight sheet can be prevented.

Fig. 2 is an explanatory view showing an example of a layer structure of a peripheral edge portion of a backlight sheet with a circuit. A colored insulating layer 111 is laminated on the non-wiring portion 141 of the peripheral edge 140 of the backlight sheet. Since the colored insulating layer 111 is laminated on the backlight sheet in a state in which the ultraviolet ray-filtered pigment 130 is uniformly dispersed, the embrittlement of the backlight sheet 16 can be prevented.

Further, the present embodiment will be described in detail.

As the transparent substrate 11, it must have the following various functions: good light transmittance; excellent long-term (about 20 years) and excellent weather resistance, less reduction in light transmittance; dust and the like are difficult to adhere; water vapor transmission rate Extremely low. As the material, a film made of an acrylic resin, a polycarbonate resin, a siloxane resin, a fluororesin or the like can be used in addition to glass. Moreover, these thin films can also be used as a composite film.

As a transparent packaging material, it must have the following functions: high transmittance of sunlight; no change in physical properties such as reduced light transmittance; and high insulation, no corrosion of other materials; no air conditions due to impatience Resin cracking, interfacial peeling, etc. caused by changes, etc. For example, a polyvinyl butyral (PVB) resin, a decyl alkane resin, a vinyl chloride resin, a polyurethane, or the like can be used. Ethylene-methyl methacrylate copolymer (EMMA), ethylene-acrylate copolymer (EAA), ionomer, polypropylene resin, etc. can also be used, and ethylene-vinyl acetate copolymer (EVA) resin can be used. . The thickness of the transparent encapsulant is preferably in the range of 100 to 1000 μm. If it is less than 100 μm, the unit will be broken; if it exceeds 1000 μm, it will not be saved.

As the packaging material, ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-propylene can be used. Ethyl ester copolymer (EAA), ionomer, polypropylene resin, polyvinyl butyral (PVB) resin, decane resin, and the like. Further, in order to make the gap between the solar battery cells inconspicuous, a colored film such as white or black is used, or a highly reflective film for re-reflecting light that is not absorbed by the surface of the solar cell to improve power generation efficiency can be used. Or a picture.

As a method of forming the encapsulant, for example, a package material can be formed by extrusion molding a mixed resin in which an ethylene-vinyl acetate copolymer (EVA) resin and other additives are mixed and heat-melted by a T die. For example, a co-extrusion method can also be used to form a film into two layers to form a package. The thickness of the encapsulating material is preferably in the range of 50 μm to 2 mm. Further, as another method, it can be formed into a sheet shape by molding by a calender.

Next, the coloring insulating layer will be described in detail.

The backlight sheet with a circuit is composed of a laminate in which a layer of a metal layer and a backlight sheet are laminated with an adhesive interposed therebetween. The metal layer is patterned to form a circuit and a wiring portion between the circuits, and then a colored insulating layer is laminated on the non-wiring portion of the peripheral edge of the backlight to form a circuit-backed backlight.

The colored insulating layer is required to have high insulation. As the insulating resin forming the colored insulating layer, a thermosetting resin, an ultraviolet curing resin, or the like can be used. As the thermosetting resin, for example, a phenol resin, an epoxy resin, an unsaturated polyester resin, a polyimide resin, a polyester resin, a fluorine resin, a siloxane resin, a polycarbonate resin, or a polyether styrene resin can be used. , polyether phthalimide resin and the like.

When the thermosetting resin is to be dried by heating, if it is heated to exceed the Tg (glass transition temperature) of the backlight sheet, it may shrink or deform due to the heat, and therefore it is necessary to confirm it.

Further, as the ultraviolet curable resin, a radical polymerization type resin such as an acrylate or an unsaturated polyester or a cationic polymerization type such as an epoxy resin can be used.

In the case of ultraviolet irradiation, since the ultraviolet curable resin is used without the heat treatment, the problem of heat shrinkage of the backlight sheet does not occur. Moreover, in comparison with the step of thermal hardening, the step of curing the ultraviolet light has a shorter hardening time and is more economical. Therefore, the productivity of the backlight sheet can be improved by using an ultraviolet curable resin. Further, by forming the ultraviolet curable resin on the non-wiring portion on the peripheral edge of the backlight sheet, the productivity of the backlight sheet can be further improved and the production cost can be reduced.

The colored insulating layer can be formed by forming a colored insulating agent which incorporates at least a pigment having ultraviolet absorbing property into an insulating resin, and coating the colored insulating agent.

As the pigment, various pigments such as inorganic pigments and organic pigments can be used. The black pigment is preferably carbon black or titanium black, and the average particle diameter is preferably from 0.01 to 0.5 μm from the viewpoints of color development, dispersibility, cost, and the like. Further, as the white pigment, titanium oxide or barium sulfate is preferable, and from the viewpoint of color development, the average particle diameter of the titanium oxide is preferably 0.1 to 1.0 μm.

Further, in the case of, for example, a black pigment, the blending amount of the pigment is preferably in the range of 1 to 4% by weight based on the weight of the colored insulating layer. If the blending amount of the black pigment is less than 1% by weight, the purple color may be lacking. The external filter has a long-term exposure to the outside of the house, and there is a case where the backlight is deteriorated or yellowed. Moreover, when the blending amount of the black pigment exceeds 4% by weight, the pigment may be excessively affected, which may adversely affect the curing of the ultraviolet curable resin, or may move to the packaging material to tightly seal the encapsulating material and the colored insulating layer. Reduced stickers.

The case of the white pigment is preferably in the range of 5 to 15% by weight based on the weight of the colored insulating layer. When the blending amount of the white pigment is less than 5% by weight, the ultraviolet filter property may be lacking, and when the film is exposed to the outside for a long period of time, the backlight sheet may be deteriorated or yellowed. Further, when the amount of the white pigment blended exceeds 15% by weight, the amount of the pigment is too large, which may adversely affect the hardening of the ultraviolet curable resin, or may move to the packaging material to make the packaging material adhere to the colored insulating layer. Reduce the embarrassment.

The colored insulating layer can be formed by a conventional method such as gravure printing, screen printing, inkjet printing or the like.

In order to obtain a high insulation level, the thickness of the colored insulating layer is preferably in the range of 5 to 25 μm. Below 5 μm, the insulation becomes insufficient; in the case of more than 25 μm, it is uneconomical because it does not obtain a higher insulation effect.

Next, an example of a method of manufacturing a backlight sheet with a circuit will be described.

The backlight sheet with a circuit is composed of a laminate in which a metal layer and a backlight sheet are bonded together with an adhesive layer interposed therebetween. The metal layer is patterned to form a circuit and a wiring portion connecting the circuits, and a colored insulating layer is further laminated on the non-wiring portion of the peripheral edge of the backlight to form a backlight sheet with a circuit.

As the adhesive for forming the adhesive layer, an adhesive for dry build-up can be used. For example, a two-liquid curing type urethane-based adhesive, a polyester urethane-based adhesive, a polyether urethane-based adhesive, an acrylic adhesive, a polyester adhesive, or the like can be used. A polyamide-based adhesive, an epoxy-based adhesive, or the like.

Examples of the diluent solvent for the adhesive include toluene, xylene, ethyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dimethylformamide, and dimethylacetamide. , methanol, ethanol and water. The coloring adhesive may be either an emulsion type or a solvent type.

The layer is then formed using the above-mentioned adhesive, for example, by a conventional method such as gravure coating, roll coating, blade coating, die coating, or the like. As the thickness of the adhesive layer, a thickness of 5 to 15 μm is preferable, and the bonding strength can be made firm. When the thickness of the layer is less than 5 μm, the strength will be insufficient; if it exceeds 25 μm, the production cost will increase. As a method of bonding, a dry lamination method can also be utilized.

Further, an extrusion lamination method using an extrusion adhesive resin can also be used. Examples of the adhesive resin include low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, ethylene methyl methacrylate copolymer (EMMA), and ethylene-acrylate copolymerization. Resin such as (EAA). The thickness of the layer is then preferably in the range of 15 to 30 μm. The thickness of the layer can then be determined based on the strength of the bond.

As the metal layer, copper foil, aluminum foil, or the like is preferable in terms of conductivity and material cost. As the patterning of the metal layer, etching processing, punching processing, or the like can also be used.

The backlight sheet has formed a circuit and a circuit piece connecting the wiring portions between the circuits. In addition, it must have a function as a back surface protection of the solar cell module. A polyolefin film which can be obtained from polyethylene terephthalate film, polybutylene terephthalate (PBT), polyethylene naphthalate film, polypropylene, polyethylene, etc.; polyphenylene sulfide (PPS) A film or a polyvinylidene fluoride (PVF) or the like is suitably selected. Further, these thin films may be used in a single layer or may be composited. For example, a layer structure of the backlight sheet may be a fluororesin/polyethylene terephthalate film/fluororesin or a polyethylene terephthalate film/fluororesin. When necessary, in order to impart gas barrier properties, that is, water vapor barrier properties, oxygen barrier properties, and the like, a layer for bonding the aluminum foil to the film or a layer of the inorganic oxide may be deposited. Further, from the viewpoint of design, it may be a layer colored into a white sheet or a black sheet.

Next, an example of a method of manufacturing a back contact type solar cell module will be described.

For example, a transparent encapsulant, a solar cell unit, a package material, and a backlight sheet with a circuit can be sequentially laminated on a transparent substrate such as a front glass, and then subjected to a usual forming method in which a pressure-sensitive adhesive layer is heated while being vacuumed. The solar cell module is formed integrally. At this time, the connection electrode of the electron extraction electrode is provided on the back surface of the solar cell, and the connection material is formed by connecting the circuit of the backlight and the connection electrode, and integrally formed. The solar cell units are formed in plural numbers, and the respective circuits are connected by a wiring portion. The wiring portion is connected to the terminal box outside the backlight sheet by a wire.

According to the present embodiment, the contact type solar cell module is formed by the non-wiring portion only at the peripheral edge of the backlight of the attached circuit. The colored insulating layer prevents embrittlement of the backlight. Further, it is possible to reduce the insulating resin used for the insulating layer, and it is possible to reduce the production cost.

Next, the second embodiment will be described in detail.

(Second embodiment)

Fig. 3 is an explanatory view showing an example of a layer structure of a contact type solar cell module according to the present invention. The solar cell module 230 is composed of a transparent substrate 21 such as a front glass, a transparent encapsulant 22, a solar cell unit 23, a package member 24, and a backlight sheet 212 with an electric circuit. On the back surface of the solar cell unit 23, a connection electrode 27 of an electron extraction electrode of a p-pole and an n-pole is provided, and a connection material 28 connecting the circuit 211 and the connection electrode is formed. A conductive material such as solder or silver paste is generally used as the connecting material 28. The circuit-backed backlight sheet 212 is formed by laminating a layer of the metal layer 220 and the backlight sheet 26 with the colored adhesive layer 210 of the pigment having the ultraviolet-filtered pigment interposed therebetween, and the metal layer is patterned to form The laminated body of the circuit 211. Further, in addition to the position where the connection electrode 27 and the circuit 211 are connected by the connecting member 28, the package member 24 is interposed and electrically insulated. Further, the transparent encapsulant 22 is also interposed between the transparent substrate 21 and the solar cell unit 23.

4A and 4B are explanatory views showing an example of a layer structure of a backlight sheet with a circuit. Fig. 4A shows a laminate 222 in which the color-bonding layer 210 of the pigment 213 having been subjected to the ultraviolet ray-filtering is interposed and the metal layer 220 and the backlight sheet 26 are bonded to each other. Further, the state in which the pigment 213 has been uniformly dispersed in the colored back layer 210 is shown. FIG. 4B shows a state in which the metal layer 220 is patterned to form the circuit 211, and the display is attached. The backlight sheet 212 of the circuit. The colored adhesive layer 210 prevents the embrittlement of the backlight sheet 26 by laminating the ultraviolet ray-removing pigment 213 on the backlight sheet 26 in a state of being uniformly dispersed.

This embodiment will be further described in detail.

In the present embodiment, the transparent base material, the transparent sealing material, and the packaging material similar to those of the first embodiment can be used. Further, the encapsulating material may be a thermoplastic resin which is thermally meltable next to the colored layer of the circuit board. Further, in the present embodiment, the package material can be formed by the same method as in the first embodiment.

The backlight sheet with the circuit will be described.

The backlight sheet with a circuit is formed by laminating a layered metal layer and a backlight material with a coloring adhesive having a pigment having ultraviolet-filtering properties interposed therebetween, and patterning the metal layer to form a circuit layer.

The colored adhesive layer can be formed by coating a coloring adhesive containing at least a pigment having a UV filter, an adhesive, and a solvent. Further, the colored adhesive layer can also be formed by extrusion molding a mixed resin in which a pigment having ultraviolet filter property is incorporated into an adhesive resin.

As the pigment having ultraviolet ray repellency, various pigments such as inorganic pigments and organic pigments can be used. From the viewpoint of versatility, price, color development property, or ultraviolet filterability, as the black pigment, carbon black or titanium black is preferable, and the average particle diameter is preferably from the viewpoints of color development, dispersibility, or cost. 0.01 to 0.5 μm. Further, as the white pigment, titanium oxide or barium sulfate is preferable, and from the viewpoint of color development, the average particle diameter of the titanium oxide is preferably 0.1 to 1.0 μm.

Further, in the case of, for example, a black pigment, the blending amount of the pigment is preferably in the range of 1 to 4% by weight based on the weight of the colored adhesive layer. When the blending amount of the black pigment is less than 1% by weight, the ultraviolet filter property may be lacking, and when the film is exposed to the outside for a long period of time, the backlight sheet may be deteriorated or yellowed. Further, in the case where the blending amount of the black pigment exceeds 4% by weight, there is a possibility that the adhesion to the sealing material or the adhesion between the sealing material and the colored adhesive layer is lowered due to the excessive amount of the pigment.

The case of the white pigment is preferably in the range of 5 to 15% by weight based on the weight of the colored back layer. When the blending amount of the white pigment is less than 5% by weight, the ultraviolet ray-removing property may be lacking, and when it is exposed to the outside for a long period of time, the backlight sheet may be deteriorated or yellowed. Further, when the blending amount of the white pigment exceeds 15% by weight, the amount of the pigment is too large, and the adhesion to the sealing material or the adhesion between the sealing material and the colored adhesive layer is lowered.

As the adhesive, an adhesive for dry lamination can be used. For example, a two-liquid curing type urethane-based adhesive, a polyester urethane-based adhesive, a polyether urethane-based adhesive, an acrylic adhesive, a polyester adhesive, or the like may be used. A polyamide-based adhesive, an epoxy-based adhesive, or the like.

Examples of the solvent include toluene, xylene, ethyl acetate, acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dimethylformamide, dimethylacetamide, methanol, and ethanol. And water, etc. The coloring adhesive may be either an emulsion type or a solvent type.

Further, in the colored adhesive layer, if necessary, an ultraviolet absorber, a light stabilizer, or the like can be contained.

The coloring adhesive layer is formed using a coloring adhesive, for example, by a conventional method such as gravure coating, roll coating, blade coating, die coating, or the like. As the thickness of the adhesive layer, a thickness of 5 to 50 μm is preferable. When the thickness of the layer is in the range of 5 to 50 μm, the bonding strength between the metal layer and the backlight sheet can be made strong, and ultraviolet rays can be efficiently filtered. When the thickness of the colored back layer is less than 5 μm, the strength will be insufficient. When the thickness of the colored back layer exceeds 50 μm, there is a problem associated with an increase in cost.

The metal layer and the backlight sheet are bonded together with the above-mentioned colored adhesive layer interposed therebetween. The lamination method can also be a dry lamination method. Further, the bonding method may be an extrusion lamination method in which a pigment having ultraviolet absorbing property is incorporated into an adhesive resin and then extruded. Examples of the adhesive resin include low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, ethylene methyl methacrylate copolymer (EMMA), and ethylene acrylate copolymer ( EAA) and other resins. In this case, by preparing a masterbatch in which a binder resin and a pigment have been blended in advance, the master batch is incorporated into an adhesive resin, and extrusion lamination is carried out to bond them. The thickness of the colored back layer is preferably in the range of 15 to 50 μm. The thickness of the colored back layer can be determined according to the adhesion strength, the coloring density, and the like.

As the metal layer, copper foil, aluminum foil, or the like is preferable in terms of conductivity and material cost. As the patterning of the metal layer, etching processing, punching processing, or the like can be used.

The backlight sheet is required to have a function as a back surface of the solar cell module while forming a substrate of a circuit on its surface. Can be from polyethylene terephthalate film, polybutylene terephthalate (PBT), A polyethylene naphthalate film, a polyolefin film such as polypropylene or polyethylene; a film such as polyphenylene sulfide (PPS) or a polyvinyl fluoride (PVF) is suitably selected. Further, the film may be used in a single layer or as a layer structure of the backlight sheet, and examples thereof include a fluororesin/polyethylene terephthalate film/fluororesin or a polyethylene terephthalate film/fluorine. Resin, etc. When necessary, in order to impart gas barrier properties, that is, water vapor barrier properties, oxygen barrier properties, and the like, a layer in which an aluminum foil is bonded to the film and a layer of the inorganic oxide is vapor-deposited can be used. Further, from the viewpoint of design, it may be a layer colored into a white sheet or a black sheet.

The rear contact type solar cell module can be formed by, for example, a conventional forming method such as a front glass laminated transparent packaging material, a solar cell, a packaging material, a backlight sheet with a circuit, and a vacuum lamination method. It is formed and manufactured.

The contact type solar cell module of the present invention can prevent embrittlement of the backlight sheet even without using solder resist. Therefore, it is possible to reduce the production cost, and it is possible to improve productivity.

Hereinafter, an embodiment of the first embodiment of the present invention will be described.

[Example 1]

A two-liquid-curing urethane-based adhesive was used to bond a 25 μm-thick polyvinyl fluoride (PVF) resin film (trade name, PV 2111, manufactured by Du Pont) to a thickness of 250 μm by a dry lamination method. A polyethylene terephthalate (trade name, S-10, manufactured by Toray Co., Ltd.) was formed to form a laminate.

Next, an electrolytic copper foil having a thickness of 35 μm was bonded to the surface of the above-mentioned polyethylene terephthalate film by a dry lamination method using a two-liquid curing type urethane-based adhesive. Thereafter, the ripening was carried out at 60 ° C for 7 days. The thickness of the subsequent agent was carried out at 12 g/m ² (dry). The polyethylene terephthalate film and the electrolytic copper foil had a bonding strength of 10 N/cm.

In addition, patterning of the electrolytic copper foil is performed by an etching method, and a backlight sheet in which a wiring portion between a circuit composed of a wiring portion and a non-wiring portion and a circuit is formed is formed.

Next, in order to form a colored insulating layer, carbon black is incorporated into an ultraviolet curable resin (trade name, UVR-150GR60, manufactured by Sun Ink Co., Ltd.), and the carbon black is blended with respect to the weight of the colored insulating layer. The coloring insulating agent was formed in such a manner that the ratio became 3% by weight. Using the colored insulating agent, a colored insulating layer is formed on the non-wiring portion of the peripheral edge of the backlight sheet by screen printing, and a backlight sheet with a circuit is formed. Further, the colored insulating layer was cured by ultraviolet treatment at 1000 mj/cm ² . The thickness of the colored insulating layer was 20 μm.

Next, an ethylene-vinyl acetate copolymer (EVA) resin film (without ultraviolet absorber) of a 200 μm package was formed, and a backlight of the above-mentioned circuit was superposed on a portion of the connection electrode and the circuit portion on the back surface of the solar cell. In the sheet, the solar cell unit, the transparent packaging material 400 μm, and the front glass were further sequentially laminated to form a rear contact type solar cell module. In the case of overlapping, the silver paste is applied to the contact portion between the connection electrode and the circuit in advance, and the module is laminated and heated to be bonded. The front glass is made of 3mm thick reinforced sodium. Calcium glass. The transparent encapsulant is an EVA resin film (without UV absorber). In the modular laminate, a vacuum was applied at 130 ° C for 3 minutes and further at 150 ° C for 30 minutes.

Hereinafter, a comparative example of the present invention will be described.

<Comparative Example 1>

A rear contact type solar cell module was produced in the same manner as in Example 1 except that the colored insulating layer of Example 1 was not formed.

<Reference example>

A rear contact type solar cell module was produced in the same manner as in Example 1 except that the colored insulating layer of Example 1 was used to form the entire surface of the backlight. The thickness of the colored insulating layer was 20 μm.

<Evaluation method>

The ultraviolet irradiation test was performed from the glass side of the front side of the fabricated rear contact type solar cell module. As the ultraviolet irradiation condition, light having an illuminance of 60 W was irradiated for 1000 hours at a wavelength of 300 to 400 nm. After the ultraviolet irradiation test, the presence or absence of embrittlement of the polyethylene terephthalate film was confirmed. As an evaluation method, it was evaluated whether the tensile breaking strength and the subsequent strength respectively met the following evaluation criteria.

Tensile breaking strength: at a tensile speed of 300 mm/min, the breaking strength is 3 N/cm or more.

Then the strength: 4N/cm or more

The evaluation results are shown in Table 1.

○: Compliance with the benchmark

×: Not meeting the benchmark

In the backlight of Example 1, the non-wiring portion including the peripheral edge was not observed, and embrittlement of the polyethylene terephthalate film was not observed. In the same manner as in Comparative Example 2, embrittlement was not observed. In Comparative Example 1, embrittlement of the polyethylene terephthalate film was observed in the non-wiring portion of the peripheral edge and the entire backlight sheet. The subsequent adhesion to the colored insulating layer is also reduced. It is understood that by forming a colored insulating layer on the non-wiring portion of the peripheral edge of the backlight of the circuit, the insulating resin used for the insulating layer can be reduced, so that the production cost can be reduced.

Hereinafter, an embodiment of the second embodiment of the present invention will be described.

[Embodiment 2]

A polyvinyl fluoride (PVF) resin film (trade name, PV 2111, manufactured by Du Pont), and thickness of a fluororesin having a thickness of 25 μm is bonded by a dry lamination method using a two-liquid-curing urethane-based adhesive. 250 μm of polyethylene terephthalate decylamine (trade name, S-10, manufactured by Toray Co., Ltd.) to form a laminate.

Next, carbon black of 3% by weight based on the adhesive is blended into a two-liquid curing type urethane-based adhesive to form a coloring adhesive, and the coloring adhesive is used to form a thickness by a dry lamination method. An electrolytic copper foil of 35 μm was attached to the surface of the above-mentioned polyethylene terephthalate film. Thereafter, the ripening was carried out at 60 ° C for 7 days. The thickness of the coloring adhesive was 12 g/m ² (dry). Further, patterning of the electrolytic copper foil was carried out by an etching method to form a backlight sheet with a circuit. At this time, the bonding strength between the polyethylene terephthalate film and the electrolytic copper foil was 10 N/cm.

Next, an ethylene-vinyl acetate copolymer (EVA) resin film (without ultraviolet absorber) of a 200 μm package was formed, and a backlight of the above-mentioned circuit was superposed on a portion of the connection electrode and the circuit portion on the back surface of the solar cell. In the sheet, the solar cell unit, the transparent packaging material 400 μm, and the front glass were further sequentially laminated to form a rear contact type solar cell module. The front glass is made of reinforced soda lime glass with a thickness of 3 mm. The transparent encapsulant is an EVA resin film (without UV absorber).

[Example 3]

Using a color-bonding resin in which 3% by weight of carbon black is incorporated into an ethylene-methyl methacrylate copolymer (EMMA) resin (trade name, Nucrel NC0809, manufactured by Mitsui Du Pont Co., Ltd.), using an extrusion lamination method The polyethylene terephthalate of the laminate of Example 3 and the electrolytic copper foil were 35 μm. The thickness of the colored adhesive resin layer was 40 μm. Further, patterning of the electrolytic copper foil was carried out by a cutting method to form a backlight sheet with a circuit. At this time, the adhesive strength of polyethylene terephthalate and copper foil was 10 N/cm. Thereafter, a post contact solar cell module was produced in the same manner as in the first embodiment.

Hereinafter, a comparative example of the present invention will be described.

<Comparative Example 2>

A backlight sheet with a circuit was produced in the same manner as in Example 2 except that carbon black was not added to the adhesive of the polyethylene terephthalate film bonded to the laminate of Example 2 and the electrodeposited copper foil. The adhesive strength of the polyethylene terephthalate film and the electrolytic copper foil was 11 N/cm. Thereafter, a post-contact solar cell module was produced in the same manner as in Example 2.

<Comparative Example 3>

Except that the carbon black was not incorporated into the ethylene-methyl methacrylate copolymer (EMMA) resin of the laminated polyethylene terephthalate film of the example 3 and the electrolytic copper foil, and Example 3 The backlight sheet with the circuit is also formed. The adhesive strength of the polyethylene terephthalate film and the electrolytic copper foil was 18 N/cm. Thereafter, a post contact solar cell module was produced in the same manner as in Example 3.

<Evaluation method>

The ultraviolet irradiation test was performed from the light-receiving side of the formed rear contact type solar cell module, that is, the front glass side. In the ultraviolet irradiation condition, light having an illuminance of 60 W was irradiated at a wavelength of 300 to 400 nm for 1000 hours. After the ultraviolet irradiation test, the tensile elongation at break was measured as an evaluation of whether or not the backlight sheet, that is, the polyethylene terephthalate film, was embrittled.

<evaluation result>

In the solar cell module to which carbon black was added in Examples 2 and 3, embrittlement of the polyethylene terephthalate film was not observed. However, embrittlement was observed in the solar cell module of carbon black which was not added in Comparative Examples 2 and 3. Further, the solar cell module in which the carbon black is added to the adhesive, bonded by the dry lamination method, or the solar cell module bonded to the adhesive resin by the extrusion lamination method is not observed. Embrittlement. It was found that the embrittlement of the polyethylene terephthalate film, that is, the backlight sheet, can be prevented by providing a colored adhesive layer which has been blended with the ultraviolet-filtering pigment.

1A‧‧‧UV

11‧‧‧Transparent substrate

12‧‧‧Transparent packaging materials

13‧‧‧Solar battery unit

14‧‧‧Package

16‧‧‧Backlight

17‧‧‧Backlit film with circuit

18‧‧‧Connecting electrode

19‧‧‧Connecting materials

111‧‧‧Colored insulation

112‧‧‧Next layer

120‧‧‧ Circuitry

121‧‧‧Wiring Department

140‧‧‧ peripheral edge

141‧‧‧ Non-wiring department

150‧‧‧Contact solar cell module after the invention

Claims (8)

A rear contact type solar cell module, which comprises a transparent substrate, a transparent sealing material, a solar cell unit, a sealing material, and a backlight sheet with a circuit laminated in sequence; the backlight of the circuit is laminated a circuit in which a colored insulating layer having a UV-filtering pigment, a patterned metal layer, and a wiring portion connecting the circuit and a laminated body of the backlight sheet are formed; the colored insulating layer is formed in the attached A non-wired portion of the peripheral edge of the backlight of the circuit. The contact type solar cell module according to claim 1, wherein a black pigment containing carbon black or titanium black is blended in the colored insulating layer, and the black pigment is blended with respect to the weight of the colored insulating layer. The ratio is from 1 to 4% by weight. The contact type solar cell module according to claim 1, wherein a white pigment containing titanium oxide or barium sulfate is blended in the colored insulating layer, and the white pigment is blended with respect to the weight of the colored insulating layer. The ratio is 5 to 15% by weight. A contact type solar cell module according to any one of claims 1 to 3, wherein the backlight sheet is formed of a polyethylene terephthalate film. A rear contact type solar cell module, which comprises a transparent substrate, a transparent sealing material, a solar cell unit, a sealing material, and a backlight sheet with a circuit; The backlight sheet with the circuit is formed of a layered body in which a metal layer is laminated, a pigmented layer having a UV-filtering pigment, and a laminate of a backlight sheet are formed; and the metal layer is patterned to form an electric circuit. The contact type solar cell module after claim 5, wherein a black pigment containing carbon black or titanium black is blended in the colored adhesive layer, and the black pigment is blended with respect to the weight of the colored adhesive layer The ratio is from 1 to 4% by weight. The contact type solar cell module according to claim 5, wherein a white pigment containing titanium oxide or barium sulfate is blended in the colored adhesive layer, and the white pigment is blended with respect to the weight of the colored adhesive layer. The ratio is 5 to 15% by weight. A contact type solar cell module according to any one of claims 5 to 7, wherein the backlight sheet is formed of a polyethylene terephthalate film.