KR20100110577A - Adhesive sheet composition for solar battery, adhesive sheet and solar battery using the same - Google Patents

Abstract

PURPOSE: An adhesive sheet composition for a solar battery, an adhesive sheet for the solar battery, and the solar battery using thereof are provided to secure the high light quantity and light transmittance. CONSTITUTION: An adhesive sheet composition for a solar battery contains an ethylene copolymer and organic peroxide. The organic peroxide is selected from the group consisting of dialkyl peroxide organic peroxide, alkylperoxyesters, and peroxyketone. The weight ratio of the ethylene copolymer and the organic peroxide is 10:50~50:10.

Description

Adhesive sheet composition for solar cell, adhesive sheet for solar cell and solar cell using same {adhesive sheet composition for solar battery, adhesive sheet and solar battery using the same}

The present invention relates to a solar cell adhesive sheet composition having a high transmittance and excellent light increase, a solar cell adhesive sheet and a solar cell using the same.

As environmental problems increase in recent years, hydro power, wind power, and solar power have come into the spotlight as clean energy. Among them, solar power generation using solar energy is growing in recent years as an energy source that is clean and useful for preventing global warming.

As a representative of this photovoltaic power generation, a solar cell using semiconductors such as monocrystalline silicon, polycrystalline silicon, amorphous silicon and the like can be given. A solar cell is a practical use of the principle of emitting electrons when sunlight is irradiated to a semiconductor.

Solar cells are generally manufactured by protecting a solar cell element such as silicon, gallium arsenide, copper-indium-selenide with an upper transparent protective member and a lower substrate protective member, and fixing the solar cell element and the protective members with an adhesive sheet.

Currently, adhesive sheets are manufactured using ethylene copolymers and organic peroxides in order to increase the power generation efficiency of solar cell devices. However, such an adhesive sheet has a problem of lowering transmittance and lowering power generation efficiency.

In order to increase the power generation efficiency, it is very important to increase the amount of light incident on the solar cell. However, the adhesive sheet applied to the conventional solar cell is difficult to secure sufficient light amount required to generate power from the incident light, thereby reducing the power generation efficiency of the solar cell element. There is a problem.

Therefore, in order to improve the power generation efficiency of the solar cell, the adhesive sheet applied to the solar cell is required to have a high transmittance and an excellent amount of incident light.

Accordingly, an object of the present invention is to provide an adhesive sheet composition for a solar cell which can not only be excellent in transmittance but also can secure a high light quantity, and can improve power generation efficiency during solar cell production.

Still another object of the present invention is to provide an adhesive sheet for a solar cell, which can continuously secure an excellent amount of incident light while having high transmittance, thereby increasing power generation efficiency.

Another object of the present invention is to provide a solar cell having excellent power generation efficiency.

In order to achieve the above object of the present invention, in the present invention,

In the adhesive sheet composition for solar cells containing an ethylene copolymer resin and an organic peroxide,

The organic peroxide may be a dialkyl peroxide organic peroxide (A) and at least one organic peroxide (B) selected from alkyl peroxy esters and peroxy ketones in a weight ratio of (A) / (B) 10/50 to 50 / It is a mixed organic peroxide mixed by the ratio of 10,

It provides at least one light diffusing agent at 0.0001 to 1 part by weight based on 100 parts by weight of the ethylene copolymer, to provide an adhesive sheet composition for a solar cell.

In order to achieve another object of the present invention, the present invention provides an adhesive sheet for a solar cell, characterized in that manufactured using the adhesive sheet composition.

For still another object of the present invention, the present invention includes a solar cell device, an upper protective material located above the solar cell device, and a lower protective material located below the solar cell device, and between the solar cell device and the protective material. At least one of the solar cells provides an adhesive sheet according to the present invention.

The adhesive sheet manufactured by the adhesive sheet composition for solar cells according to the present invention maintains a high amount of incident light without decreasing transmittance, and thus, the solar cell manufactured by using the solar cell manufactured by using the adhesive sheet composition may increase power generation efficiency.

Hereinafter, the present invention will be described in more detail, but for the purpose of describing the present invention, it is not intended to limit the scope of the present invention.

A solar cell adhesive sheet composition according to the present invention is a mixture obtained by mixing an ethylene copolymer resin with at least one organic peroxide (B) selected from a dialkyl peroxide organic peroxide (A), an alkyl peroxy ester and a peroxy ketone. Organic peroxide and a light diffusing agent.

The adhesive sheet composition for solar cells which consists of the said ethylene copolymer, an organic peroxide, and a light diffusing agent may further contain at least 1 sort (s) of additive chosen from a crosslinking adjuvant, a silane coupling agent, and a ultraviolet absorber.

Ethylene copolymer

In the adhesive sheet composition for solar cells according to the present invention, the ethylene copolymer may be used in an amount of 20 to 40 wt%, preferably 25 to 35 wt%, in consideration of transparency, flexibility, and impregnation of organic peroxides. . In addition, the ethylene copolymer uses a melt flow rate of 0.1 to 100 g / 10 min, preferably 0.5 to 50 g / 10 min at 190 ° C. and 2160 kg load in consideration of moldability and mechanical properties.

Specific examples of suitable ethylene copolymers include ethylene vinyl ester copolymers such as ethylene vinyl acetate copolymer, ethylene methyl acrylate copolymer, ethyl ethylene acrylate copolymer, ethylene methyl methacrylate copolymer, and ethylene isobutyl acrylate copolymer. Ethylene-unsaturated carboxylic acid copolymers such as ethylene-unsaturated carboxylic acid ester copolymers such as ethylene-acrylic acid n-butyl copolymers, ethylene-acrylic acid copolymers, ethylene-methacrylic acid copolymers, and ethylene-acrylic acid isobutyl-methacrylic acid copolymers And the ionomer etc. can be illustrated as a representative example. Among these, in consideration of the suitability to the required physical properties of the adhesive sheet composition for solar cells such as moldability, transparency, flexibility, adhesion, and light resistance, and impregnation of organic peroxides, it is preferable to use an ethylene-vinyl acetate copolymer. desirable.

Examples of commercially available ethylene-vinyl acetate copolymers include MA-10 (32 wt% vinyl acetate content and 40 g / 10 min melt flow rate) of TPC, PV 1650 (33 wt% vinyl acetate content, melt flow) from DuPont Rate is 31g / 10min) PV 1400 (32% vinyl acetate content, 43g / 10min melt flowrate) PV 1410 (32% vinyl acetate content, 43g / 10min melt flowrate) It is possible.

It is preferable that the said ethylene copolymer is contained 96-99.5 weight part with respect to 100 weight part of adhesive sheets compositions for solar cells. If the ethylene copolymer is more than 99.5 parts by weight there is a problem that the curing is not, when less than 96 parts by weight there is a problem that the adhesive strength is inferior.

Organic peroxide

The organic peroxide in the adhesive sheet for solar cells according to the present invention is a mixed organic peroxide obtained by mixing a dialkyl peroxide organic peroxide (A) with at least one organic peroxide (B) selected from alkyl peroxy esters and peroxy ketones. do.

The dialkyl peroxide organic peroxide (A) may be used an organic peroxide having a half-life temperature of 130 to 160 ° C, preferably 135 to 150 ° C.

As said dialkyl peroxide (A), dicumyl peroxide (135 degreeC), 1, 3-bis (2-t- butyl peroxy isopropyl) hexane (137 degreeC), 2, 5- dimethyl- 2, 5-bis (Tertiary butyl peroxy) hexane (140 ° C.), t-butyl cumyl peroxide (142 ° C.), di-t-butyl peroxide (149 ° C.) and the like can be used.

At least one organic peroxide (B) selected from the alkyl peroxy ester and the peroxy ketone may be an organic peroxide having a half-life temperature of 100 to 130 ° C. for 1 hour.

The alkyl peroxy ester and peroxy ketone are t-butyl peroxy isobutylate (102 ° C.), t-butyl peroxy maleic acid (110 ° C.), t-butyl peroxy isopropyl carbonate (119 ° C.), t-butyl Peroxy 2-ethylhexyl carbonate (121 ° C), 2,5-dimethyl-2,5-bis (benzoylperoxy) hexane (118 ° C), t-butylperoxy acetate (123 ° C), t-butylperoxy Alkyl peroxy esters, such as benzoate (125 degreeC), 1,1-bis (t-butylperoxy) 3,3,5-trimethyl cyclohexane (112 degreeC), 1,1-bis (t-butylperoxy ) Cyclohexane (112 ° C.), 1,1-bis (t-amylperoxy) cyclohexane (112 ° C.), 2,2-bis (t-butylperoxy) butane (119 ° C.) and the like may be used. .

The use ratio of the said organic peroxide (A) and (B) used by this invention is (A) / (B) of 10 / 50-50 / 10 in weight ratio. The organic peroxide (A) has a problem in the stability of a sheet manufacturing process that the use ratio is less than 10 with respect to (B), and when the use ratio exceeds 50, there exists a problem that the fall of the transmittance | permeability resulting from yellowing becomes severe. In addition, the organic peroxide (B) may cause problems in stability of the sheet manufacturing process and sheet stretching when the use ratio exceeds 50 for (A), and when the use ratio is less than 10, suppression of a decrease in transmittance due to the occurrence of yellowing It does not work. Therefore, it is preferable to mix and use organic peroxides (A) and (B) within the said range.

Moreover, the usage-amount of the mixed organic peroxide which mixed organic peroxide (A) and (B) can use 0.2-2 weight part with respect to 100 weight part of ethylene copolymers, Preferably 0.5-1.6 weight part can be used. If the amount of the mixed organic peroxide is less than 0.2 parts by weight, there is a problem in that the ethylene copolymer cannot be sufficiently crosslinked. If the amount of the mixed organic peroxide is more than 2 parts by weight, the crosslinking rate may be increased, but a decrease in transmittance due to yellowing may be prevented. There is no problem.

Light diffusing agent

In the adhesive sheet composition for a solar cell according to the present invention, a light diffusing agent may be generally used, and at least one light diffusing agent selected from organic particles and inorganic particles may be used alone or in combination.

For example, the light diffusing agent may use crosslinked or uncrosslinked fine particles of an organic material selected from silicon, acrylic, styrene, methyl methacrylate and styrene copolymers, polycarbonates, and olefins, or silica or talc. Fine particles of an inorganic material selected from calcium carbonate, barium sulfate, titanium dioxide (TiO ₂ ), and the like may be used. Especially, it is preferable to use acryl-type microparticles | fine-particles as said light-diffusion agent.

According to the present invention, the light diffusing agent may be included in an amount of 0.0001 to 1 part by weight, and more preferably 0.01 to 0.5 part by weight, based on 100 parts by weight of the ethylene copolymer. When the light diffusing agent is less than 0.0001 parts by weight, an increase in incident light amount may not be obtained, and when the content is greater than 1 part by weight, the transmittance of light and the amount of incident light may be deteriorated.

In this case, it is preferable to use a light diffusing agent having a refractive index of 1.1 to 1.8. If the refractive index is less than 1.1, the amount of incident light cannot be increased. If the refractive index is more than 1.8, the visible light transmittance is less than 92%.

In addition, the light diffusing agent preferably uses an average particle diameter in the range of 0.1 ~ 50㎛ to increase the amount of incident light without lowering the visible light transmittance to less than 92%, the average in consideration of dispersibility It is more preferable to use the particle diameter whose range is 2-30 micrometers. remind If the average particle diameter of the light diffusing agent is less than 0.1 μm, the amount of incident light cannot be increased. If the average particle diameter of the light diffusing agent is more than 50 μm, the transmittance is less than 92%.

Various additives

The adhesive sheet composition for solar cells according to the present invention may contain various other additives as necessary. Such additives may be exemplified by crosslinking agents, silane coupling agents, ultraviolet absorbers and light stabilizers.

The silane coupling agent may improve the adhesion with the low iron tempered glass and the back sheet when manufacturing the solar cell after the sheet production with the adhesive sheet composition for solar cells according to the present invention.

-아미노프로필트리메톡시실란, N-(β-아미노에틸)--아미노프로필메틸디메톡시실란, -아미노프로필트리에톡시실란, -글리시독시프로필트리메톡시실란, -메타아크릴록시프로필트리메톡시실란 등을 예시할 수 있다.Examples of the silane coupling agent include compounds having a hydrolyzable group such as an alkoxy group together with a ball saturation group such as a vinyl group, an acryloxy group or a methacrylic group, an amino group, an epoxy group and the like. As the silane coupling agent, specifically N- (β-aminoethyl)-

-Aminopropyltrimethoxysilane, N- (β-aminoethyl) -aminopropylmethyldimethoxysilane, -aminopropyltriethoxysilane, -glycidoxypropyltrimethoxysilane, -methacryloxypropyltrimeth Oxysilane, etc. can be illustrated.

It is suitable to mix | blend the said silane coupling agent about 0.1-2 weight part with respect to 100 weight part of ethylene copolymers. When blended outside the above range, there is a problem that the effect of the adhesive strength is lowered.

The ultraviolet absorber is effective in blocking ultraviolet rays and inhibiting the decomposition of the adhesive sheet for solar cells by ultraviolet rays. As said ultraviolet absorber, various types, such as a benzophenone type, a benzotriazole type, a triazine type, and a salicylic acid ester type, are mentioned. Commercially available UV absorbers include TINUVIN 328, TINUVIN 1577 FF, TINUVIN 120, and Cimasorb 81 from Ciba, Sumitosorb Chemical, Sumisorb 130, Sumisorb 350, Sumisorb 110, Seesorb 102 from Ciprocasei, seesorb 707, seesorb 101 may be used.

It is suitable to mix | blend the said ultraviolet absorber about 0.1-2 weight part with respect to 100 weight part of ethylene copolymers. If the ultraviolet absorber is added in less than 0.1 parts by weight, there is no UV blocking effect, when added in excess of 2 parts by weight causes a problem of yellowing.

The crosslinking aid is effective for promoting the crosslinking reaction to increase the degree of crosslinking of the ethylene copolymer, and specific examples thereof include polyunsaturated compounds such as polyallyl compounds and poly (meth) acryloxy compounds. More specifically, the crosslinking aid is polyallyl compound such as triallyl isocyanurate, triallyl cyanurate, diallyl phthalate, diallyl fumarate, diallyl maleate, ethylene glycol diacrylate, ethylene glycol dimethacryl And poly (meth) acryloxy compounds such as trimethylolpropane trimethacrylate, dinynebenzene and the like.

It is effective to mix | blend the said crosslinking adjuvant in the ratio of about 0.5-5 weight part with respect to 100 weight part of ethylene copolymers. If the crosslinking aid is added in less than 0.5 parts by weight, there is no effect of promoting crosslinking, and when added in excess of 5 parts by weight, there is a problem of yellowing.

The light stabilizer may be added to those commonly used in the art within the usual addition range.

In the present invention, there is provided an adhesive sheet for solar cells manufactured using the composition described above.

The adhesive sheet for solar cells which concerns on this invention can be manufactured by the well-known sheet shaping | molding method using a T-die extruder, a calendar molding machine, etc. For example, an organic peroxide, a light diffusing agent and a silane coupling agent, a crosslinking aid, a UV absorber, a light stabilizer, etc., added to the ethylene copolymer as necessary, are previously dry blended and supplied to the hopper of the T-die extruder to form a sheet. It can obtain by extrusion molding.

The adhesive sheet manufactured in this way can ensure an excellent amount of incident light while having a visible light transmittance of 92% or more. In addition, the adhesive sheet has a 1000 hour heat test (85 ° C.) ΔYI value of 2 or less during a reliability test of a solar cell, a 1000 hour moisture test (85 ° C. 90% RH) of ΔYI value of 2 or less, and a weather test of 500 hours (UV harshness) Test) ΔYI -1.5 or less, and shrinkage upon curing is 2% or less.

The present invention provides a solar cell comprising the adhesive sheet.

The solar cell according to the present invention includes a solar cell element, an upper protective material positioned above the solar cell element, and a lower protective material positioned below the solar cell element, wherein the solar cell includes at least one of the solar cell element and the protective material. The solar cell adhesive sheet according to the present invention is included.

The solar cell having the above structure can be manufactured by attaching the solar cell element, the upper protective material and the lower protective material to the adhesive sheet at a temperature at which the adhesive sheet melts without substantially decomposing the organic peroxide. For example, the solar cell is temporarily bonded to the adhesive sheet according to the present invention between the solar cell element and the low iron tempered glass as the upper protective material and between the solar cell element and the back sheet as the lower protective material, and then heated up (100 to 180 ° C.). If sufficient adhesion | attachment and crosslinking of an adhesive sheet are advanced, it can manufacture.

Hereinafter, the present invention will be described in more detail by the following examples and comparative examples, but the following examples are only some specific examples of the present invention, and are not intended to limit or limit the protection scope of the present invention.

≪ Example 1 >

0.2 weight of 2,5-dimethyl-2,5 di (t-butylperoxy) hexane (Alchema Luphenox 101) as an organic peroxide (A) to 100 parts by weight of ethylene / vinyl acetate copolymer (TPC MA-10) 0.6 parts by weight of t-butylperoxy-2ethylethylhexylcarbonate (Alchema TBEC) (A / B = 0.333) as the organic peroxide (B), and 0.01% by weight Sumitomo XC1A (refractive index 1.49 average particle diameter: 30 µm) as the light diffusing agent. 0.5 parts by weight of Shin-Etsu Co., Ltd. KBM 503 as a silane coupling agent, 0.35 parts by weight of Sumitomo Chemical Co., Ltd. as a UV absorber, and 0.15 parts by weight of Shivasa Tinuvin 770 as a UV stabilizer were impregnated with a mixer at 25 ° C. for 1 hour. (Screw diameter 40mm, L / D = 26), the adhesive sheet of 0.5 mm was produced at the processing temperature of 85 degreeC.

<Example 2>

An adhesive sheet was prepared in the same manner as in Example 1 except that 0.02 parts by weight of Sumitomo XC1A (refractive index 1.49 average particle diameter: 30 μm) was used in Example 1 above.

<Example 3>

An adhesive sheet was prepared in the same manner as in Example 1 except that 0.1 part by weight of Sumitomo XC1A (refractive index: 1.49 average particle diameter: 30 μm) was used as the light diffusing agent in Example 1.

<Example 4>

An adhesive sheet was prepared in the same manner as in Example 1, except that 0.01 parts by weight of Kolon Diasphere S-30P (refractive index: 1.57 average particle diameter: 30 μm) was used instead of Sumitomo XC1A in Example 1 above.

<Example 5>

An adhesive sheet was prepared in the same manner as in Example 1, except that 0.02 parts by weight of Kolon Diasphere S-30P (refractive index 1.57 average particle diameter: 30 μm) was used instead of Sumitomo XC1A in Example 1 above.

<Example 6>

An adhesive sheet was prepared in the same manner as in Example 1, except that 0.01 parts by weight of Dongyang Silicon DSP1820 (refractive index 1.4 average particle diameter: 2 μm) was used instead of Sumitomo XC1A in Example 1.

Comparative Example 1

0.2 parts by weight of Alkema Lufenox 101 with an organic peroxide (A) and 100 parts by weight of ethylene / vinyl acetate copolymer (TPC MA-10) and 0.6 parts by weight of Alkema Rufenox TBEC with an organic peroxide (B) 0.333 parts by weight of silane coupling agent, Shin-Etsu Co., Ltd. KBM 503 0.5 parts by weight, UV absorber by Sumitomo Chemical sumisorb 130 0.35 parts by weight, UV stabilizer by Tinuvin 770DF 0.15 parts by impregnation at 25 ℃, 1 hour in a mixer (Screw diameter 40mm, L / D = 26), the adhesive sheet of 0.5 mm was produced at the processing temperature of 85 degreeC.

Comparative Example 2

An adhesive sheet was produced in the same manner as in Comparative Example 1 except that 0.2 part by weight of Alchema luphenox 101 and 0.8 part by weight of Alchema TBEC (A / B = 0.25) were used as the organic peroxide (A).

Experimental Example

Using the adhesive sheets prepared in Examples 1 to 6, Comparative Examples 1 and 2, the physical properties were measured as follows, and the results are shown in Table 1.

1. Transmittance Measurement

A 0.5 mm adhesive sheet was prepared between low iron reinforced glass and melt-bonded at 150 ° C. for 20 minutes using a vacuum bonding machine. The transmittance was measured using a magnetic spectrophotometer (UV 2450 manufactured by SHIMADZU Corporation) in accordance with JIS K7105.

2. Intensity Measurement

Insert 0.5mm adhesive sheet prepared between the low iron reinforced glass and melt-bond with 150 ℃ for 20 minutes using a vacuum bonding machine, and use the angle photometer (NIPPON DENSHOKU GC 5000L) at 0, 30, and 60 degrees Luminance was measured.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Transmittance (%) Visible light 93 93 93 93 93 93 93 93 magnitude 0 degrees 98632 92462 90076 93435 99526 96921 87997 87684 30 degrees 98947 96475 82252 89664 91862 91640 74117 74342 60 degrees 80794 83109 80895 64230 77524 73408 57978 57862

As shown in Table 1, in the case of the embodiment including the light diffusing agent according to the present invention, it can be confirmed that the transmittance is the same level and excellent light compared to the comparative examples without the light diffusing agent.

Claims (7)

In the adhesive sheet composition for solar cells containing an ethylene copolymer and an organic peroxide, The organic peroxide may be a dialkyl peroxide organic peroxide (A), at least one organic peroxide (B) selected from alkyl peroxy esters and peroxy ketones in a weight ratio of (A) / (B) 10/50 to 50 It is mixed organic peroxide mixed by making ratio of / 10, The adhesive sheet composition for solar cells which further contains at least 1 type of light diffusing agent (C) at 0.0001-1 weight part with respect to 100 weight part of said ethylene copolymers. The adhesive sheet composition of claim 1, wherein the adhesive sheet composition for solar cells has a visible light transmittance of 92% or more upon curing. The refractive index of the said light diffusing agent is 1.1-1.8, The adhesive sheet composition for solar cells of Claim 1 characterized by the above-mentioned. The adhesive sheet composition for solar cells according to claim 1, wherein an average particle diameter of the light diffusing agent is 0.1 um to 50 um. The adhesive sheet composition for solar cells according to claim 1, wherein the organic peroxide is contained in an amount of 0.2 to 2 parts by weight based on 100 parts by weight of the ethylene copolymer. The adhesive sheet for solar cells manufactured using the adhesive sheet composition for solar cells of any one of Claims 1-5. A solar cell element, an upper protective material located on top of said solar cell element, and a lower protective material located on a substrate of said solar cell element, wherein at least one of said solar cell element and said protective material is an adhesive sheet for solar cells of claim 6 Solar cell comprising a.