CN103151407A - Solar cell rear panel and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of solar cells, in particular to a solar cell rear panel and a preparation method of the solar cell rear panel. The solar cell rear panel and the preparation method of the solar cell rear panel aim at solving the problems that an existing solar cell rear panel is high in production cost and poor in interlayer adhesiveness. The solar cell rear panel comprises a resin sheet basic layer. Chemical pretreatment layers are coated on two surfaces of the basic layer. A bonding layer is coated on each pretreatment layer. A protection layer is coated on each bonding layer. The chemical pretreatment layers are composed of water-solubility polyurethane, water-solubility acrylic ester or modified water-solubility polyester in a solidified mode. The solar cell rear panel is high in binding power between the polyester basic layer and the fluorine material protection layer and low in production cost. The preparation method of the solar cell rear panel is simple in process and easy to operate.

Description

A kind of solar cell backboard and preparation method thereof

Technical field

The present invention relates to technical field of solar batteries, be specifically related to a kind of solar cell backboard (or claiming the solar energy backboard) and preparation method thereof.

Background technology

Solar cell is to be light energy conversion the device of electric energy by photoelectric effect.The advantages such as, spatter property permanent owing to having, flexibility, it is considered to a kind of novel energy of following main development, and in the near future, solar cell can the Substitute For Partial conventional energy resource, becomes the main body of world energy supplies.

Solar cell is a stepped construction normally, is followed successively by from top to bottom clear glass cover plate/sealant ethene-vinyl acetate copolymer (EVA glue)/cell piece/EVA glue/backboard.Whole solar cell is by framing up and form sealing four sides after above-mentioned each material lamination again.The Main Function of its dorsulum is the overall mechanical strength that improves solar panel, intercepts simultaneously water vapor permeable in sealant, to ensure the useful life of cell piece.Therefore, solar cell backboard must have good anti-electrical breakdown, ageing-resistant, weather, the characteristic such as corrosion-resistant.

Solar cell backboard is produced by the multilayer film thermoforming way mostly at present.Take the most frequently used TPT as example, its preparation method is that independently film is hot-forming by the bonding of macromolecule adhesive with three layers of polyvinyl fluoride/PETG/polyvinyl fluorides (being called for short PVF/PET/PVF).Pet layer wherein is as matrix, and main rising insulated and supporting role; Two outer field PVF can play ageing-resistant and corrosion-resistant effect owing to containing fluorin radical on molecular skeleton.In order to obtain the performances such as better barrier, weatherability, can use Kynoar (PVDF) to substitute PVF.

There are the problems such as the high and interlaminar adhesion of material cost is low in the production of Present Domestic solar energy backboard, in backsheet layer, the production of PET basement membrane is mature on the whole, but the production technology difficulty of PVF or PVDF is larger, almost can not autonomous production, basically rely on external import, cause thus the higher defective of backboard membrane material cost.In addition, because fluoropolymer surface can be low, making PET and PVF(or PVDF) bonding strength is inadequate between rete, and easily cause be separated from each other between each layer of backboard membrane and cause the hydraulic performance decline such as barrier, weatherability, corrosion resistance of whole backboard membrane, thereby affect the useful life of battery.Therefore, adopt the multilayer film hot press forming technology, very harsh to the requirement of macromolecule adhesive formula.

The method that solves at present caking property problem between backboard cost and each layer has two kinds, on the one hand, substitutes traditional fluorine film with fluororesin-coated formation fluorine layer, reaches the purpose that reduces costs; On the other hand, carry out corona treatment at fluorine film or polyester base film surface, suitably improve the caking property between two membranes.Publication number is CN101272903, open day is the Chinese invention patent of on 09 24th, 2008, a kind of solar cell backboard that adopts fluorine-containing coat replacement fluorine film is provided, this fluorine-containing coat is to have imported the fluoropolymer that solidifies functional group, in order to improve the caking property between fluorine layer and basic unit or sealant layer.Publication number is CN101515603A, open day is the Chinese invention patent application of on 08 26th, 2009, a kind of solar cell backboard is provided, has provided three kinds of versions: the first is the sheet material one side coating fluorine-containing coat in impermeability, the compound fluorine-contained film in the another side; The second is respectively to be coated with fluorine-containing coat in the sheet material two sides of impermeability; The third is the sheet material one side coating fluorine-containing coat in impermeability, then fluorine-containing coat outside the coating surface coating, be coated with fluorine-containing coat in the sheet material another side at last.The backboard membrane of above structure is partly or entirely replaced the fluorine rete by the coating fluorine-containing coat, thereby reduces to a certain extent material cost, also improves caking property between each layer of backboard membrane from the improvement of fluorine material or adhesive.

Due to the solar cell permanence of service time (need to use out of doors more than 20 years), keep whole battery component to have good barrier, weatherability and corrosion resistance, to guarantee its useful life, the caking property between each layer of backboard membrane is most important.The applicant thinks except fluororesin or adhesive are done improvement, perhaps fluorine film or polyester base film surface carried out being necessary polyester base material is made further improvements outside corona treatment, to improve as far as possible the adhesive property between each layer of backboard membrane.

Summary of the invention

In order to solve production cost height and the poor defective of interlaminar adhesion of existing solar energy backboard, the invention provides a kind of solar cell backboard and preparation method thereof.Cohesive force between the polyester base film of solar cell backboard provided by the invention and fluorine material protection layer is higher, and production cost is lower.Preparation method's technique of solar cell backboard provided by the invention is simple, easy operating.

For achieving the above object, the present invention adopts following technical scheme:

The invention provides a kind of solar cell backboard, described backboard comprises resin sheet basic unit (abbreviation basic unit/basement membrane, or base copolyester/polyester base film); Two surface-coateds of described basic unit have the Chemical Pretreatment layer, are coated with tack coat on described pretreatment layer, are coated with protective layer on described tack coat; Described Chemical Pretreatment layer is formed by soluble polyurethane, water-soluble acrylic ester or modified soluble curable polyester.

It is polyester material that described resin sheet basic unit adopts material, is selected from a kind of in PETG (PET), polybutylene terephthalate (PBT) (PBT), polyethylene naphthalate (PEN) and modification by copolymerization resin thereof.

The thickness of described resin sheet basic unit is 100-250 μ m.

Described polyester material is prepared into membranaceous or laminated structure by stretch processes.

Further, be added with the 5-40%(weight percentage in described resin sheet basic unit) inorganic particle, the particle diameter of described inorganic particle is 0.01-1 μ m.

Described inorganic particle is packing material, is selected from the combination of a kind of in aluminium oxide, aluminum sulfate, calcium carbonate, magnesium carbonate, alumina silicate, magnesium silicate, silicon dioxide or titanium dioxide or at least two kinds.Above-mentioned inorganic filling material be added with weather resistance and the ageing-resistant performance that helps improve basic unit.

Further, described protective layer is the fluorine-containing coat that fluorine resin coating forms.

Described fluorine resin coating is mixed emulsion, comprises fluoropolymer, solvent, curing agent, filler and auxiliary agent.Described fluoropolymer is selected from the combination of a kind of in polyvinyl fluoride, Kynoar, polytetrafluoroethylene, poly(perfluoropropene), chlorotrifluoroethylene-alkyl vinyl ether, vinylidene fluoride resin, Kynoar-tetrafluoroethene-hexafluoro isopropyl olefine resin copolymer or at least two kinds; Described solvent is selected from the combination of a kind of in toluene, ortho-xylene, acetone, butanone, ethyl acetate or butyl acetate or at least two kinds; Described curing agent is selected from the combination of a kind of in divinylbenzene, trimethylol-propane trimethacrylate, triallyl cyanurate, 2-hydroxy-2-methyl-1-phenylacetone or at least two kinds; Described filler is selected from the combination of a kind of in quartz particles, mica particles, titanium dioxide granule or at least two kinds.Described fluorine resin coating directly is coated in the surface of described tack coat, obtains fluorine-containing protective layer after hot curing.

Further, described bonding layer material comprises resin matrix and curing agent.

Described resin matrix can be selected with the polyacrylate system of curing property functional group or polyester system, as poly-hydroxy acrylate, poly-amino acrylates, poly-carboxy acrylic ester, with the polyester of hydroxyl, with the polyester of carboxyl etc., wherein, the polyester with carboxyl or hydroxyl that preferably has better caking property and hydrolytic resistance.Described curing agent can be selected a kind of in epoxy curing agent, isocyanate curing agent or carbodiimides curing agent.

Further, described tack coat is formed by the adhesive curing of bi-component hot setting.

Further, the thickness of described resin sheet basic unit is 100-250 μ m, and the thickness of described protective layer is 20-50 μ m, and the thickness of described tack coat is 2-10 μ m.

On the other hand, the invention provides the preparation method of above-mentioned solar cell backboard, in this preparation method, described Chemical Pretreatment layer chemical material used first is mixed with coating fluid (aqueous solution), then coating fluid is coated substrate surface, moisture in the coating that at last coating fluid is formed is removed, and forms the Chemical Pretreatment layer.

Further, described Chemical Pretreatment layer chemical material used is selected from soluble polyurethane, water-soluble acrylic ester or modified soluble polyester; Described coating fluid comprises following component (described percentage is weight percentage):

Soluble polyurethane, water-soluble acrylic ester or modified soluble polyester 5%-10%

Crosslinking agent 1%-2%

Water 80%-90%

Isopropyl alcohol 4%-8%,

The weight percentage of above-mentioned soluble polyurethane, water-soluble acrylic ester or modified soluble polyester accounts for the percentage of coating fluid total weight for its solid composition.The too low effectiveness that do not reach of above-mentioned content, the too high processing technology that makes is had any problem.

Further, described preparation method comprises the steps:

(1) inorganic particle and polyester material are passed through melting mixing, extruding pelletization, be prepared into the masterbatch that contains 50% inorganic filler;

(2) preparation of resin sheet basic unit: 30% polyester is had the light material, after the 30% anti-stick inorganic filler masterbatch that connects polyester masterbatch and 40% step (1) gained mixes, melt extrude, longitudinal stretching, after being cooled to room temperature, at basement membrane online coating of both sides while coating fluid, coating weight is 5-15g/m², after pre-heating drying, cross directional stretch, thermal finalization is cooled to room temperature, and traction, rolling obtain described resin sheet basic unit;

(3) coating tack coat: a surface-coated bonding layer material of the resin sheet basic unit that makes in step (2), baking is 5-10 minute under 120 ℃, makes tack coat;

(4) preparation of protective layer:

The preparation fluoro-containing coating, described fluoro-containing coating comprises fluorine resin, curing agent, curing accelerator, solvent, titanium dioxide, the UV absorbent,

Fluorine resin is dissolved in solvent, then adds curing agent, titanium dioxide filler, UV absorbent, stirring forms fluorine-containing protection layer for paint;

Then with fluorine-containing protection layer for paint blade coating on tack coat, under 120 ℃ the baking 20-30 minute, make the protective layer that dried thickness is 20-50 μ m;

(5) in kind be coated with tack coat and protective layer on another surface of base copolyester, make described solar cell backboard.

Further, in described step (2), concrete process conditions are as follows:

Polyester there is the light material, after the anti-stick inorganic filler masterbatch that connects polyester masterbatch and step (1) gained mixes, 260-280 ℃ of lower melting, extrude slab, at 60-90 ℃ of lower longitudinal stretching 2.5-3.5 doubly, after being cooled to room temperature, be coated with online simultaneously coating fluid in basement membrane both sides, after 80-100 ℃ of lower pre-heating drying, under 100-120 ℃ laterally stretching 3-4 doubly, 200-230 ℃ of lower thermal finalization 20-30 second.

Further, in described step (4), prepare fluoro-containing coating according to following formula:

Further, the formula of described Chemical Pretreatment layer coating fluid following (described content is weight percentage):

On the other hand, the invention provides a kind of solar cell backboard film, described backboard comprises resin sheet basic unit; Be provided with the Chemical Pretreatment layer on two surfaces of described basic unit, described pretreatment layer is outside equipped with tack coat, and described tack coat is outward protective layer.

Further, the material of described Chemical Pretreatment layer is selected from soluble polyurethane, water-soluble acrylic ester or modified soluble polyester.

Further, described protective layer is fluor resin coating.

Compared with prior art; solar cell backboard provided by the invention; by substrate surface is carried out Chemical Pretreatment, the basic unit two sides are added with can improve the chemical substance of basic unit and protective layer compatibility, obtain and fluororesin and the better basement membrane of adhesive compatibility.The basic unit of solar cell backboard provided by the invention and protective layer bonding are more firm.The present invention makes basic unit and protective layer compound tense do specific (special) requirements to adhesive and fluororesin by the backboard substrate surface is carried out Chemical Pretreatment, can adopt known any one fluororesin and adhesive in the field, only needs to consider that its result of use gets final product.Therefore, solar cell backboard provided by the invention not only has better adhesive property, barrier, weatherability, and has reduced the production technology of Material Cost and solar cell backboard and the difficulty of component design.Preparation method's technique of solar cell backboard provided by the invention is simple, easy operating.

Description of drawings

Fig. 1 is the structural representation of solar cell backboard provided by the invention;

Wherein, 1 is basic unit, and 2 is protective layer, and 3 is tack coat, and 4 is the Chemical Pretreatment layer.

Embodiment

As shown in Figure 1, solar cell backboard provided by the invention comprises resin sheet basic unit 1; Two surface-coateds of described basic unit 1 have Chemical Pretreatment layer 4, are coated with tack coat 3 on described pretreatment layer 4, are coated with protective layer 2 on described tack coat 3.

The preparation method of the described solar cell backboard of following embodiment 1-4 comprises the steps:

(1) described base layer of resin material adopts following formula (described content is weight percentage):

PET has light material 50%

The anti-stick masterbatch 30% that connects of PET

Titanium dioxide 20%

Wherein titanium dioxide first has the light material by melting mixing, extruding pelletization with 20%PET, is prepared into the titanium dioxide weight percentage and is 50% PET masterbatch;

(2) prepare basic unit:

PET masterbatch with step (1) obtains has light material and the 30% anti-stick masterbatch that connects to mix with 30%PET.The anti-stick even masterbatch of described PET contains the silicon dioxide of 0.25%-0.50%.

After above-mentioned polyester raw material section is mixed, 260-280 ℃ of lower melting, extrude slab, 3 times of 60-90 ℃ of lower longitudinal stretchings, be cooled to room temperature; Carry out simultaneously online coating in basement membrane two sides and process, adopt respectively different acrylate as the coating fluid material, coating weight is 5-15g/m²After 80-100 ℃ of lower pre-heating drying, laterally stretch 3.5 times under 100-120 ℃, 200-230 ℃ of 20 seconds of lower thermal finalization, be cooled to room temperature, traction, rolling, obtaining thickness is the PET basement membrane of 100-250 μ m.

(3) preparation tack coat:

A surface of the PET basic unit that makes in step (2) uses the tack coat coating fluid to be coated with, and the approximately thick tack coat 3 of 5 μ m was made in baking in 5-10 minute under 120 ℃;

(4) preparation protective layer:

Described protective layer is fluorine-containing protective finish, adopts following formula (described content is weight percentage):

Fluorine resin is dissolved in solvent, then adds the auxiliary agents such as curing agent, filler, the formation mixed emulsion stirs.

Then with fluorine-containing protection layer for paint blade coating on tack coat 3, baking is 20-30 minute under 120 ℃, makes the protective layer 2 of doing the thick 20-50 of being about μ m.

(5) in kind be coated with tack coat 3 and protective layer 2 on another surface of PET basic unit 1, make solar cell backboard of the present invention.Its structure as shown in Figure 1.

The method of testing of the adhesive property of solar cell backboard provided by the invention, barrier, weatherability is summarized as follows:

(1) caking property test

The gained rear panel compound film is cut into wide 15mm, be about the galley proof of 1m, at galley proof one end, protective layer is peeled away a little.At puller system (for example; the INSTRON universal testing machine that Britain Instron company produces) clamp respectively basic unit and protective layer on; direction stretching with 180 ° of angles makes basic unit and protective layer continue to peel away fully; read shown pulling force data during stretching, namely get power required when peeling off.Peeling force is larger, and the adhesive property of backboard membrane is just better.

(2) permeability test

Barrier characterizes by water vapor transmittance, and with reference to the disclosed method of ISO15106-3 testing standard, the test environment temperature is 35 ± 5 ℃, and relative humidity is 95 ± 5%.

(3) weatherability test

Weatherability characterizes by lamination, puncture voltage and metachromatism.Adopt the disclosed method of solar panel authentication/solar photovoltaic cell panel IEC61215 standard to carry out layering to sample and detect, test condition is: temperature is 85 ℃, and relative humidity is 85%RH, time is 2000 hours, observe sample and have or not layering, without being layered as OK, be layered as NO.Adopt the disclosed method of ASTMF-149 standard to carry out the puncture voltage test to sample.The detection method of metachromatism is: sample is placed in 1KW ultraviolet xenon lamp irradiation 150 hours under 60 ℃, observation has or not variable color, is OK without variable color, and it is NO that variable color is arranged.

Embodiment 1

Prepare solar cell backboard by preceding method, wherein the PET groundwork thickness is 175 μ m, adopts acrylic emulsion as Chemical Pretreatment layer coating material, the formula of coating fluid following (described content is weight percentage):

Above-mentioned coating fluid is 8g/m in the coating weight of substrate surface²The weight percentage of aforesaid propylene yogurt liquid is the percentage that the solid composition of acrylic emulsion accounts for the coating fluid total weight.

Coating tack coat coating fluid on above-mentioned Chemical Pretreatment layer, described tack coat coating fluid formula following (described content is weight percentage):

Press preceding method at the surface-coated fluorine protective layer of tack coat, the dried thickness of fluorine protective layer is 30 μ m.

Gained solar cell backboard (also can be described as composite membrane) performance measurement the results are shown in Table 1.

Embodiment 2

Prepare solar cell backboard by preceding method, wherein the PET groundwork thickness is 200 μ m, adopts acrylic resin as Chemical Pretreatment layer coating material, the formula of coating fluid following (described content is weight percentage):

Above-mentioned coating fluid is 12g/m in the coating weight of substrate surface²The weight percentage of aforesaid propylene yogurt liquid is the percentage that the solid composition of acrylic emulsion accounts for the coating fluid total weight.

Use following tack coat coating fluid formula (described content is weight percentage):

Press preceding method at the surface-coated fluorine protective layer of tack coat, the dried thickness of fluorine protective layer is 28 μ m.

The performance measurement of gained composite membrane the results are shown in Table 1.

Embodiment 3

Prepare solar cell backboard by preceding method, wherein the PET groundwork thickness is 225 μ m, adopts acrylic emulsion as Chemical Pretreatment layer coating material, the formula of coating fluid following (solid part quality percentage composition):

Above-mentioned coating fluid is 10g/m in the coating weight of substrate surface²The weight percentage of aforesaid propylene yogurt liquid is the percentage that the solid composition of acrylic emulsion accounts for the coating fluid total weight.

Use following tack coat formulation for coating material (described content is weight percentage):

Press preceding method at the surface-coated fluorine protective layer of tack coat, the dried thickness of fluorine protective layer is 35 μ m.

The performance measurement of gained composite membrane the results are shown in Table 1.

Embodiment 4

Prepare solar cell backboard by preceding method, wherein the PET groundwork thickness is 250 μ m, adopts the polyurethane acroleic acid emulsion as Chemical Pretreatment layer coating material, the formula of coating fluid following (described content is weight percentage):

Above-mentioned coating fluid is 8g/m in the coating weight of substrate surface²The weight percentage of aforesaid propylene yogurt liquid is the percentage that the solid composition of acrylic emulsion accounts for the coating fluid total weight.

Use following tack coat coating fluid formula (described content is weight percentage):

Press preceding method fluorine protective layer on the surface-coated of tack coat, the dried thickness of fluorine protective layer is 36 μ m.

The performance measurement of gained composite membrane the results are shown in Table 1.

The performance test results of table 1. embodiment 1-4 gained solar cell backboard

Embodiment 5

Prepare solar cell backboard by preceding method, wherein the thickness of PET basic unit is 100 μ m; Described Chemical Pretreatment layer coating fluid used comprises following component (content is weight percentage):

According to the described recipe configuration tack coat of embodiment 1 coating fluid, the thickness of described tack coat is 2 μ m.

The formula of described protective layer is as follows:

The thickness of described protective layer is 20 μ m.

The performance measurement of gained composite membrane the results are shown in Table 2.

Embodiment 6

Prepare solar cell backboard by preceding method, wherein the thickness of PET basic unit is 250 μ m; Described Chemical Pretreatment layer coating fluid used comprises following component (content is weight percentage):

According to the described recipe configuration tack coat of embodiment 2 coating fluid, the thickness of described tack coat is 10 μ m.

The formula of described protective layer is as follows:

The thickness of described protective layer is 50 μ m.

The performance measurement of gained composite membrane the results are shown in Table 2.

Embodiment 7

Prepare solar cell backboard by preceding method, wherein the thickness of PET basic unit is 150 μ m; Described Chemical Pretreatment layer coating fluid used comprises following component (content is weight percentage):

According to the described recipe configuration tack coat of embodiment 3 coating fluid, the thickness of described tack coat is 8 μ m.

The formula of described protective layer is as follows:

The thickness of described protective layer is 35 μ m.

The performance measurement of gained composite membrane the results are shown in Table 2.

Embodiment 8

Prepare solar cell backboard by preceding method, wherein the thickness of PET basic unit is 150 μ m; Described Chemical Pretreatment layer coating fluid used comprises following component (content is weight percentage):

According to the described recipe configuration tack coat of embodiment 4 coating fluid, the thickness of described tack coat is 4 μ m.

The formula of described protective layer is as follows:

The thickness of described protective layer is 40 μ m.

The performance measurement of gained composite membrane the results are shown in Table 2.

The performance test results of table 2. embodiment 5-8 gained solar cell backboard

Comparative Examples 1

For PET relatively basic unit after the surface chemistry coating is processed to caking property institute produce an effect, we have arranged Comparative Examples, namely use without chemically treated PET basic unit and carry out the compound of fluorine protective layer.In Comparative Examples, the formula of PET raw material used, protective layer coating solution, tack coat coating fluid and technique are identical with embodiment 1, and the PET groundwork thickness is 200 μ m, and the fluorine protective layer thickness is 30 μ m.The performance measurement of gained composite membrane the results are shown in Table 3.

Comparative Examples 2

Prepare solar cell backboard by preceding method, wherein the thickness of PET basic unit is 230 μ m; Described Chemical Pretreatment layer coating fluid used comprises following component (content is weight percentage):

According to the described recipe configuration tack coat of embodiment 2 coating fluid, the thickness of described tack coat is 8 μ m.

The formula of described protective layer is as follows:

The thickness of described protective layer is 45 μ m.

In gained composite membrane Chemical Pretreatment layer coating fluid used, soluble polyurethane content is too low, does not reach treatment effect, and film performance is relatively poor, and its measurement result sees Table 3.

Comparative Examples 3

Prepare solar cell backboard by preceding method, wherein the thickness of PET basic unit is 200 μ m; Described Chemical Pretreatment layer coating fluid used comprises following component (content is weight percentage):

According to the described recipe configuration tack coat of embodiment 2 coating fluid, the thickness of described tack coat is 6 μ m.

The formula of described protective layer is as follows:

The thickness of described protective layer is 40 μ m.

Water-soluble acrylic ester too high levels in gained composite membrane Chemical Pretreatment layer coating fluid used, processing difficulties, cost is higher, and the solar cell backboard performance of gained is inhomogeneous, and its measurement result sees Table 3.

Comparative Examples 4

Prepare solar cell backboard by preceding method, wherein the thickness of PET basic unit is 250 μ m; Described Chemical Pretreatment layer coating fluid used comprises following component (content is weight percentage):

According to the described recipe configuration tack coat of embodiment 3 coating fluid, the thickness of described tack coat is 15 μ m.

The formula of described protective layer is as follows:

The thickness of described protective layer is 50 μ m.

Soluble polyurethane content in above-mentioned Chemical Pretreatment layer coating fluid is high, and the thickness of above-mentioned tack coat is large, and in protective layer, fluorine resin content is too low, and the combination property of gained composite membrane is relatively poor, and its performance measurement the results are shown in Table 3.

The performance test results of table 3 Comparative Examples 1-4 gained solar cell backboard

The performance test data of the solar cell backboard that provides from the embodiment of table shown in 1-3 and Comparative Examples can draw; backboard basic unit selects suitable Chemical Pretreatment layer coating fluid formula used; after the surface chemistry preliminary treatment, can effectively strengthen the caking property between basic unit and protective layer.Simultaneously, select suitable component and proportioning, barrier property and the weather resistance of gained composite membrane are better.

As mentioned above, we are illustrated according to aim of the present invention.But the present invention is not limited to above-described embodiment and method, and the practitioner of correlative technology field can carry out different variations and enforcement in the scope of the technology of the present invention license.

Claims (10)

1. a solar cell backboard, is characterized in that, described backboard comprises resin sheet basic unit; Two surface-coateds of described basic unit have the Chemical Pretreatment layer, are coated with tack coat on described pretreatment layer, are coated with protective layer on described tack coat; Described Chemical Pretreatment layer is formed by soluble polyurethane, water-soluble acrylic ester or modified soluble curable polyester.

2. solar cell backboard according to claim 1, is characterized in that, is added with the 5-40%(weight percentage in described resin sheet basic unit) inorganic particle, the particle diameter of described inorganic particle is 0.01-1 μ m.

3. solar cell backboard according to claim 1, is characterized in that, described protective layer is the fluorine-containing coat that fluorine resin coating forms.

4. solar cell backboard according to claim 1, is characterized in that, described bonding layer material comprises resin matrix and curing agent.

5. solar cell backboard according to claim 1, is characterized in that, the thickness of described resin sheet basic unit is 100-250 μ m, and the thickness of described protective layer is 20-50 μ m, and the thickness of described tack coat is 2-10 μ m.

One of according to claim 1 to 5 described solar cell backboard the preparation method, it is characterized in that, described Chemical Pretreatment layer chemical material used first is mixed with coating fluid, then coating fluid is coated substrate surface, moisture in the coating that at last coating fluid is formed is removed, and forms the Chemical Pretreatment layer.

7. the preparation method of solar cell backboard according to claim 6, is characterized in that, described Chemical Pretreatment layer chemical material used is selected from soluble polyurethane, water-soluble acrylic ester or modified soluble polyester; Described coating fluid comprises following component (described percentage is weight percentage):

Soluble polyurethane, water-soluble acrylic ester or modified soluble polyester 5%-10%

Crosslinking agent 1%-2%

Water 80%-90%

Isopropyl alcohol 4%-8%,

The weight percentage of above-mentioned soluble polyurethane, water-soluble acrylic ester or modified soluble polyester accounts for the percentage of coating fluid total weight for its solid composition.

8. the preparation method of solar cell backboard according to claim 6, is characterized in that, described preparation method comprises the steps:

(1) inorganic particle and polyester material are passed through melting mixing, extruding pelletization, be prepared into the masterbatch that contains 50% inorganic filler;

(2) preparation of resin sheet basic unit: 30% polyester is had the light material, after the 30% anti-stick inorganic filler masterbatch that connects polyester masterbatch and 40% step (1) gained mixes, melt extrude, longitudinal stretching, after being cooled to room temperature, at basement membrane online coating of both sides while coating fluid, coating weight is 5-15g/m², after pre-heating drying, cross directional stretch, thermal finalization is cooled to room temperature, and traction, rolling obtain described resin sheet basic unit;

(3) coating tack coat: a surface-coated bonding layer material of the resin sheet basic unit that makes in step (2), baking is 5-10 minute under 120 ℃, makes tack coat;

(4) preparation of protective layer:

The preparation fluoro-containing coating, described fluoro-containing coating comprises fluorine resin, curing agent, curing accelerator, solvent, titanium dioxide, the UV absorbent,

Fluorine resin is dissolved in solvent, then adds curing agent, titanium white powder, UV absorbent, stirring forms fluorine-containing protection layer for paint;

Then with fluorine-containing protection layer for paint blade coating on tack coat, under 120 ℃ the baking 20-30 minute, make the protective layer that dried thickness is 20-50 μ m;

(5) in kind be coated with tack coat and protective layer on another surface of base copolyester, make described solar cell backboard.

9. the preparation method of solar cell backboard according to claim 8, is characterized in that, in described step (2), concrete process conditions are as follows:

Polyester there is the light material, after the anti-stick inorganic filler masterbatch that connects polyester masterbatch and step (1) gained mixes, 260-280 ℃ of lower melting, extrude slab, at 60-90 ℃ of lower longitudinal stretching 2.5-3.5 doubly, after being cooled to room temperature, be coated with online simultaneously coating fluid in basement membrane both sides, after 80-100 ℃ of lower pre-heating drying, under 100-120 ℃ laterally stretching 3-4 doubly, 200-230 ℃ of lower thermal finalization 20-30 second.

10. the preparation method of solar cell backboard according to claim 8, is characterized in that, in described step (4), prepares fluoro-containing coating according to following formula: