CN103442880B - The manufacture method of solar cell sealing sheet material - Google Patents

Abstract

The present invention is the manufacture method of solar cell sealing sheet material, described manufacture method carries out following operation successively: operation (a): by by heating, the resin combination of melting is shaped to sheet, then cool, thus obtain the operation of operation sheet; Operation (b): at least one surface heating of the operation sheet that will be obtained by above-mentioned operation (a) 22 ~ 55 seconds, adds at this operation hankering making the temperature on this surface to reach the temperature of more than the fusing point of the resin combination forming this surface portion; Operation (c): making in above-mentioned operation (b) by the temperature that heated the surface of operation sheet is particular range, then to this surface pressing dandy roll, in the operation of this surface formation embossed shapes.By the present invention, can low cost and to manufacture heat shrink efficiently little, and be formed with the solar cell sealing sheet material of embossed shapes clearly.

Description

The manufacture method of solar cell sealing sheet material

Technical field

The present invention relates to the manufacture method of solar cell sealing sheet material.Particularly, relate to that to be suitable for manufacturing heat shrink little, and surface is formed with the manufacture method of the sheet of the solar cell sealing sheet material of projection clearly.

Background technology

In recent years, from the viewpoint of effective utilization of resource, the preventing of environmental pollution, solar cell sunshine being directly changed into electric energy receives publicity, and has thus carried out various exploitation.Solar cell is generally configured to be between the sensitive surface guard member of representative and the back-protective part being called as backboard with glass substrate, with solar cell sealing sheet material (hereinafter referred to as seal stock) sealed solar energy battery unit.

As solar module, the crystallization silicon type solar cell generally following manufacture of main flow.First, laminated glass substrate, seal stock, solar battery cell (silicon generating element), seal stock and backboard successively.Sealing sheet material is generally made up of vinyl-vinyl acetate copolymer (hereinafter referred to as EVA).Then by vacuum lamination, this laminated body is heated under vacuo, seal stock heating and melting is carried out crosslinking curing.Like this, the bubble-freely bonding solar module of each member of formation is manufactured.

In the manufacture of such solar module, if the contraction during heating of seal stock is large, then due to this contraction distortion, silicon generating element is damaged sometimes, or the position of unit is sometimes moved.Therefore, for seal stock, require that contraction during heating is little.In addition in recent years, in order to effectively utilize silicon metal resource, reduce cost for universal solar module, about the lower thickness to 100 of silicon generating element μm, and then become and be easy to damaged.Therefore, the requirement making the heat shrink of seal stock reduce is strong further.Therefore, have studied the various methods of the heat shrink rate reducing seal stock.(such as, patent document 1).

In addition, except above-mentioned to except requirement when manufacturing, for solar module, in order to Long-Time Service after fabrication, its reliability is extremely important.As the representative undesirable condition occurred in the solar module of Long-Time Service, the reduction of generated energy of have the bad orders such as the stripping between solar battery cell and seal stock, expansion, accompanying therewith.The reason of these undesirable condition phenomenons may not be clear and definite, but be studied from the raw material aspect forming seal stock.Such as, have studied adjustment form the viscosity of the EVA of seal stock method (patent document 2), add the method (patent document 3) etc. of silane coupler to improve the adhesive strength of solar battery cell and seal stock.

In addition, various research has also been carried out from the configuration aspects of seal stock.In order to the expansion etc. preventing Long-Time Service adjoint, each member of formation of the inside modules after just manufacturing is important so that bubble-free state is bonding as far as possible.Therefore, in order to be easy to the object of leadage air when vacuum lamination, attempt forming various projection, the depressions such as embossed shapes on the surface of seal stock.In addition, these projections, depression cause the objects such as solar battery cell is damaged, the operability of raising seal stock to be formed to prevent sometimes due to pressing pressure during lamination.About pattern of indentations, detailed protocol (patent document 4,5) is proposed to its shape, degree of depth etc.

As described above, when manufacturing seal stock, while the heat shrink reducing seal stock, forming embossed shapes clearly on the surface of seal stock become important.As the method proposed up to now, when disclosing the sheet that casting uses the extruder such as double screw extruder to extrude from T-shaped die head, on sheet, form embossed shapes mouth mould is immediately below, then carry out the method (patent document 6) of the annealing in process reducing heat shrink as required.

Prior art document

Patent document

Patent document 1: Japanese Unexamined Patent Publication 2000-084996 publication

Patent document 2: Japanese Unexamined Patent Publication 2002-170971 publication

Patent document 3: Japanese Unexamined Patent Publication 2000-183382 publication

Patent document 4: Japanese Unexamined Patent Publication 2006-134970 publication

Patent document 5: Japanese Unexamined Patent Publication 2002-185027 publication

Patent document 6: Japanese Unexamined Patent Publication 2010-100032 publication

Summary of the invention

Invent problem to be solved

The manufacture method of patent document 6 is, after the surface formation embossed shapes of the sheet (hereinafter referred to as operation sheet) in manufacturing process, carries out annealing in process to this operation sheet.Therefore, if heated fully by operation sheet to make the heat shrink of seal stock reduce, be then formed in the embossed shapes collapse on the surface of operation sheet by this heating.If the contrary heating in order to keep embossed shapes to relax operation sheet, then annealing in process becomes insufficient.Like this, in the manufacture method of patent document 6, the reduction having heat shrink concurrently is very difficult with forming embossed shapes lucidly.

In addition, as the method for the heat shrink of reduction seal stock, generally speaking, as patent document 1 is also disclosed, employ when resin molding is carried with the conveyer with multiple roller, make the peripheral speed of the roller of entrance side faster than the peripheral speed of the roller of outlet side, and make operation sheet shrink the method reducing heat shrink.But in the method, owing to being stretched by sheet in annealing in process, therefore the removing of heat shrink is insufficient, need the implemented for long periods annealing in process at 1 ~ 2 minute.

In addition, the situation that the seal stock be made up of EVA contains crosslinking agent is many, and the forming temperature of operation sheet becomes low temperature, therefore a large amount of residual overstrain on operation sheet.And this overstrain is often uneven at the width of the operation sheet of wide cut.If the operation sheet of such state is carried out annealing in process as described above, then the flatness that sheet occurs is impaired, and thickness becomes uneven, or the undesirable condition such as operation sheet is tortuous in annealing in process.In addition, by the multiple roller clamping pressurization of the operation sheet of such state, it is very difficult for implementing embossing processing etc. continuously.

Therefore, the object of the invention is, provide and while the heat shrink fully reducing seal stock, and the manufacture method of embossed shapes clearly can be formed on the surface of seal stock.

For solving the method for problem

In order to solve above-mentioned problem, the feature of the manufacture method of solar cell sealing sheet material of the present invention is, carries out following operation (a), operation (b) and operation (c) successively.

Operation (a): by the resin combination of melting is shaped to sheet by heating, then cool, thus obtain the operation of operation sheet

Operation (b): at least one surface heating of the operation sheet that will be obtained by above-mentioned operation (a) 22 ~ 55 seconds, adds at this operation hankering making the temperature on this surface to reach the temperature of more than the fusing point of the resin combination forming this surface portion

Operation (c): will be (fusing point-10 DEG C of the resin combination of above-mentioned formation surface portion) ~ (fusing point+20 DEG C of the resin combination of above-mentioned formation surface portion) by the temperature on the surface of warmed-up operation sheet in above-mentioned operation (b), then to this surface pressing dandy roll, the operation of embossed shapes is formed on this surface

The effect of invention

According to the present invention, can low cost and to manufacture heat shrink efficiently little, and be formed with the solar cell sealing sheet material of embossed shapes clearly.

Accompanying drawing explanation

Fig. 1 is the generalized schematic of an example of the manufacture method showing solar cell sealing sheet material of the present invention.

Fig. 2 is the generalized schematic of an example of the manufacture method of the solar cell sealing sheet material shown in the past.

Fig. 3 illustrates to be determined at the figure that one side forms the method for the height of the projection of bossed solar cell sealing sheet material.

Fig. 4 illustrates to be determined at the figure that two sides forms the method for the height of the projection of bossed solar cell sealing sheet material.

Fig. 5 is the figure of the length D on the base of display projection.

Detailed description of the invention

[manufacture method of solar cell sealing sheet material]

The manufacture method of solar cell sealing sheet material of the present invention carries out following operation (a), operation (b) and operation (c) successively.

Operation (a): by the resin combination of melting is shaped to sheet by heating, then cool, thus obtain the operation of operation sheet.

Operation (b): at least one surface heating of the operation sheet that will be obtained by above-mentioned operation (a) 22 ~ 55 seconds, adds at this operation hankering making the temperature on this surface to reach the temperature of more than the fusing point of the resin combination forming this surface portion.

Operation (c): making in above-mentioned operation (b) by the temperature on the surface of warmed-up operation sheet is (fusing point-10 DEG C of the resin combination of above-mentioned formation surface portion) ~ (fusing point+20 DEG C of the resin combination of above-mentioned formation surface portion), then to this surface pressing dandy roll, the operation of embossed shapes is formed on this surface.

Below, for the manufacture method of solar cell sealing sheet material of the present invention, be described with reference to accompanying drawing.Fig. 1 is the generalized schematic of the embodiment of one of display manufacture method of the present invention.

[operation (a): film making process]

First, operation (a) is described.Operation (a) is, material resin is shaped to sheet, is cooled and obtains the operation of operation sheet.Below, operation (a) is called film making process.

In film making process in Fig. 1, be provided with at high temperature by material resin and additive fusing and mixing extruder 11, reduce resin pressure change and make the gear pump 31 of the thickness stabilisation of sheet, be extruded into the die head 12 of sheet by by mixing molten resin, the operation sheet cooling curing of the high temperature be extruded be shaped to polishing roll 13a, 13b and 13c of the operation sheet of solid.

As extruder 11, single screw extrusion machine, double screw extruder can be used.When using double screw extruder, be preferred from the viewpoint of the mixing property etc. of productivity, resin and additive.When using single screw extrusion machine, owing to being full of by resin in extruder, therefore the pressure change of the die portion of extruder front end is smaller, does not thus need necessarily to arrange weigh feeder such as gear pump 31 grade.When using double screw extruder, owing to not being in the state be filled in extruder, therefore preferred the weigh feeders such as gear pump 31 are set between extruder and die head.

Put into material resin in extruder 11 and additive can drop in advance with the mixture that mixer, mixer etc. mix, also can separately drop into.In addition, the midway side direction feed additive from extruder can be used, or if the additive of liquid then carries out the method etc. of adding with injection pump etc.

Although temperature when carrying out mixing by material resin with additive and the kind of resin used, viscosity are relevant, be preferably the scope of (fusing point of material resin+10 DEG C) ~ (fusing point of material resin+60 DEG C).In addition, so-called fusing point in the present invention, is measure in (DSC) at means of differential scanning calorimetry, has carried out endothermic peak temperature when heating up with 10 DEG C/min.When the EVA sheet generally used as seal stock, in order to make EVA be cross-linked, often contain organic peroxide as additive.Therefore, should be noted that and do not make organic peroxide decomposes and carry out mixing as far as possible.Therefore, as resin temperature, when such as fusing point is the EVA of about 70 DEG C, preferably carry out mixing the scope of 80 ~ 130 DEG C.Be more preferably the scope of 100 ~ 120 DEG C.If be less than 80 DEG C, then mixing property becomes insufficient, has the possibility of the uniformly dispersed reduction of additive.Consequently, the possibility of the degraded appearance of seal stock is had.If more than 130 DEG C, then when coordinating organic peroxide, organic peroxide can decompose, and the quality of seal stock is unstable, and continuous production also reduces sometimes in addition.

In addition, in the operation of Fig. 1, as the method for film making process sheet, be provided with extruder, but also can use shaping etc. the known distinct methods undertaken by stack.

By extruder 11 grade material resin and additive melted and carried out mixing molten resin, use die head 12 and be extruded as sheet.As die head 12, T-shaped die head, circular mode can be used first-class.Flat die head, owing to becoming the wide shape of width according to the sheet width that will extrude, if be therefore installed on extruder, becomes T-shaped, is therefore generically and collectively referred to as T-shaped die head.In addition, for T-shaped die head, in the difference such as width holdup time, flow velocity of die head, the problem such as in uneven thickness of width when being therefore easy to heating process sheet in the problem such as thickness deviation, operation (b) occurs.In order to address these problems, also preferably use cylindric circular die.Circular die is, for resin extruded one-tenth is cylindric, cut it thus be shaped to the die head of the cylindrical shape of sheet, the physical property of the width of sheet is easy to become more even.

In addition, when using T-shaped die head, multiple extruder also can be used to be extruded by different resin combinations, making operation sheet be that lamination is formed by coextrusion methods such as feed block mode, multimode head modes.Form by forming such lamination, each layer can separating necessary function, can reduce costs by regulating additive capacity as seal stock.

Use operation sheet polishing roll 13a, 13b, 13c of extruding of die head 12 and be formed as sheet.Polishing roll be for molten resin pair of rolls clamping pressurization is carried out simultaneously the thickness of sheet and prima facie figuration, the operation piece conveying device that is made up of multiple roller.The each roller formed possess be adjusted to be suitable for the cooling of molten resin, the temperature of plastic property mechanism, adjust the mechanism of gap between each roller and moulding pressure.In addition, as required, preferably by flowing through the water transfer of cooling water isothermal to prevent the adhesion of operation sheet, mouldability is improved.The temperature of cooling water is preferably adjusted to the scope of 0 ~ 30 DEG C.Be positioned at the polishing roll 13a of side, most upstream in polishing roll according to the composition of used resin, the resin of high temperature is easy to the surface being adhered to roller sometimes, therefore preferably at surface winding silicon rubber etc., release property is improved.In addition in order to make transporting improve, the 13b of the opposed roll of the polishing roll 13a being positioned at side, most upstream is also preferably made to be the metallic roll of the configuration of surface with sand planar.About the surface roughness of sand planar, 10 the mean roughness Rz defined in JISB0601-1994 are preferably the scope of about 2 ~ 10 μm.At the surface of polishing roll 13a winding silicon rubber etc., and when making the 13b of opposed roll be the metallic roll of the configuration of surface with sand planar, the thickness of the silicon rubber on the surface of polishing roll 13a is preferably 3 ~ 10mm, is more preferably 4 ~ 8mm.If the thickness of silicon rubber is less than 3mm, then the transfer printing of the pattern of sand planar becomes insufficient, sometimes for carrying operation sheet that free roll of operation sheet etc. adheres.If the thickness of silicon rubber is more than 10mm, then in the heat of rubber surface accumulation of heat from molten resin, resin of therefore sometimes adhering on roller.

[operation (b): annealing in process operation]

Next operation (b) is described.The object of operation (b) is, the overstrain that in removing film making process, shaping operation sheet has, makes the heat shrink of operation sheet reduce.For operation (b), the heater 16 can enumerated with being arranged in annealing furnace 15 heats, while by the method for operation sheet etc. on multiple conveying roller 17.Below, operation (b) is called annealing operation.

For the heater 16 of heating process sheet, as long as can heating process sheet, be not particularly limited, the known methods such as ceramic heater, stainless steel heater, sheath heater can be used.Particularly by the mode of infrared heating sheet owing to can heat equably on the thickness direction of sheet, be therefore preferred.In addition, the heating undertaken by the heating agent such as hot blast, steam, the method etc. contacted with warmed-up roller can also preferably be used.These heating means can be used alone, and also can combine some methods and use.

For carrying the conveying roller 17 of operation sheet, in order to carry by warmed-up operation sheet, preferred release property is excellent.Therefore, can be used in by compounds such as embossing processing, thermal spray metal, metal oxides and establish the roller irregular metallic roll being coated with the fluororesin such as polytetrafluoroethylene (PTFE), fluorinated ethylene propylene copolymer, perfluoroalkoxyalkane on surface.Or the surperficial circumvolution that can be used in metallic roll has carried out the paper, film etc. of the coating process of release property and the roller obtained.The imparting means of these release properties there is no need to be particularly limited to, and can use known method.As the degree of the release property of these rollers, preferably by the method for JISZ0237-2009 defined, be the material of below 5N/mm to the peel strength of ニ チ バ Application Co., Ltd. cellophane adhesive tape.In addition, about the conveying roller 17 in stove, can control the situation of its speed individually according to the contraction of operation sheet owing to efficiently can remove heat shrink, be therefore preferred.

Heater 16 and conveying roller 17, be arranged in annealing furnace 15, and when making to try one's best few with the contact of extraneous air, the temperature stabilization in stove, the heat treatment of operation sheet is stablized, and is therefore preferred.In addition, in order to make the object of the homogeneous temperature ground stabilisation in stove, will be one of preferred configuration in warm-air supply to stove.

In addition as required, preferably a pair roller 14 is located at the upstream of annealing furnace 15.By arranging roll 14, can block the impact of annealing in process operation on film making process, be therefore preferred.Specifically, contraction during heating process sheet can be prevented the impact of film making process, or make the supply stabilisation of operation sheet of annealing operation.

In addition, preferably between the outlet and dandy roll 20 of annealing furnace 15, be provided with sheet in advance and take out roller 18.Sheet taking-up roller 18 undertakes the effect from annealing furnace 15 removal process sheet.If do not have sheet to take out roller 18, then deform near operation sheet between the roller of outlet side and embossing working roll 20 is stretched in the roller 17 sometimes in annealing furnace.In addition, during annealing in process, the heat shrink of operation sheet exists uneven at the width of operation sheet and produces fold etc. sometimes, and therefore in order to remove this fold, sheet takes out roller 18 and is also preferably Stretching rollers (bow action roller).In addition preferably sheet takes out roller 18 and give release property in advance in the same manner as the conveying roller 17 in stove.

In addition, sheet takes out roller 18, if its surface temperature is too low, be then sometimes cooled to the operation sheet of dandy roll supply, the transferability of embossed shapes reduces.On the contrary, if surface temperature is too high, then operation sheet is adhered to sheet and takes out roller 18 sometimes, and the conveying of operation sheet becomes difficulty.Therefore, the surface temperature of sheet taking-up roller 18 preferably adjusts the scope that temperature is 20 ~ 80 DEG C in advance.Preferably be set to or its following surface temperature equal with the temperature of the operation sheet that annealing furnace exports further in advance.As chankings takes out the surface temperature of roller 18 higher than the surface temperature from annealing furnace operation sheet out, then operation sheet is adhered to roller sometimes.

In order to prevent the temperature of operation sheet from reducing, annealing furnace 15 is preferably as far as possible short with the distance of dandy roll 20.Therefore, many heel pieces also can be set and take out roller 18, but be preferred time less, preferably at the most less than 3, be more preferably 1 or 2.

When annealing in process operation and ensuing operation (c) being carried out continuously, preferably control the surface temperature from annealing furnace 15 operation sheet out and the surface temperature being imported into the operation sheet in dandy roll operation (c).Therefore, in order to hold the surface temperature of operation sheet exactly, and measure the exit portion of annealing furnace 15 and be about to the surface temperature of the operation sheet before carrying out embossing processing, thus non-contact infrared thermometer 33 is preferably set.In addition, preferably multiple contactless thermometer is also set in annealing furnace 15, measures the surface temperature of operation sheet.

In annealing in process operation, carry out heating until make the maximum temperature at least one surface of operation sheet become the temperature of more than the fusing point of the resin combination forming this surface portion.To the surface of this warmed-up side, in ensuing operation (c), implement embossing processing.Here, so-called " forming the resin combination of surface portion ", when operation sheet is single-layer sheet, is the resin combination forming this operation sheet, when operation sheet be lamination have a laminated sheet of multiple layers, be the resin combination of the layer on the surface forming warmed-up side.Even if implement the annealing in process making maximum temperature be only to be less than the temperature of the fusing point of resin combination such, the effect reducing heat shrink rate is also insufficient, or needs process for a long time.In addition, the maximum temperature on surface is preferably in the temperature range of (forming the fusing point+5 DEG C of the resin combination of the surface portion of warmed-up side) ~ (forming the fusing point+35 DEG C of the resin combination of the surface portion of warmed-up side).If the temperature in annealing in process is too high, then operation sheet is adhered to conveying roller sometimes, or flatness reduces, or in ensuing operation (c), produces fold as reason.Such as, when the operation sheet be made up of the EVA resin of fusing point 71 DEG C, the surface in annealing in process operation be up to the scope that temperature is preferably 76 ~ 106 DEG C.

The time of heating process sheet, namely operation sheet is trapped in the time in annealing furnace is in the scope of 22 ~ 55 seconds.This heat time is, for the operation sheet be cooled by polishing roll 13, make the surface temperature of operation sheet reach more than the melting temperature required time with in the total reaching the time of carrying out the annealing in process for reducing heat shrink after more than melting temperature.If the heat time is less than 22 seconds, then the removing of heat shrink becomes insufficient.Even if the heat time heated more than 55 seconds, effect also can be saturated, is only that the length of annealing furnace is ineffectually elongated.The lower limit of heat time is preferably more than 22 seconds, is more preferably more than 25 seconds.As long as the upper limit of heat time can remove heat shrink fully, the preferred short time, be preferably less than 45 seconds, be more preferably less than 40 seconds.

[operation (c): embossing manufacturing procedure]

Next operation (c) is described.Operation (c) is, implements embossing processing to the operation sheet being become the condition of high temperature by the heating in annealing operation, forms the operation of embossed shapes on operation sheet surface.In operation (c), be provided with the dandy roll 20 for forming embossed shapes on operation sheet, embossing opposed roll 19 and chill roll 21.After, this operation (c) is called embossing manufacturing procedure.

On the surface of dandy roll 20, apply with the embossed shapes that operation sheet will be formed the engraving having overturn this embossed shapes accordingly.The embossed shapes that operation sheet is formed is randomly shaped, geometry pattern etc., as long as determine as required.But, if the formation of embossed shapes is insufficient, then operation sheet transporting, be easy to stick together when being rolled into web-like, or not easily leadage air when making solar module, has the possibility becoming the reason producing bubble in module.Hemispherical, the cone-shaped such as pyrometric cone, quadrangular pyramid, hexagonal cone, circular cone can be adopted to the pattern of the engraving that the surface of dandy roll applies, make their top be flat trapezoidal shape.In addition, these shapes can be the pattern of mixing existence.Wherein, hemispherical and/or corner taper is preferably.Here " hemispherical and corner taper ", the hemispherical engraving mixing the pattern existed with corner taper is referred to.From when seal stock is to the pushing of solar battery cell, be not vulnerable to concentrated load, and can consider scatteredload aspect equably, preferably hemispherical.In addition, not easily occur from the uneven of reverberation of seal stock, the aspect that has excellent surface quality is considered, is preferably corner taper.And, in order to show these features that is hemispherical and corner taper, being also preferably mixing and having pattern that is hemispherical and corner taper.Deposited in case, as long as respective ratio is according to more needing which kind of feature and arbitrary decision hemispherical mixing with corner taper.It is all particularly preferably hemispheric pattern.

When the engraving on dandy roll surface is excessively dark, add the large pressing pressure of man-hour requirement at embossing, equipment becomes large-scale.Therefore, although the degree of depth of the engraving of dandy roll is relevant with the thickness of operation sheet, be preferably in the scope of 65 ~ 350 μm.In addition, the degree of depth of the engraving of so-called dandy roll, represent the distance on the surface (not implementing the part of carving) from the center of dandy roll to dandy roll with from the center of dandy roll to the difference of the distance of the deepest part of the recess carved (part of paddy).The degree of depth of this engraving, according to JISB0601 (2001), is represented by the maximum height Pz (μm) using surface roughness measurement machine to measure.

The depression of the degree of depth 1 ~ 20 μm is preferably applied further on the surface of dandy roll.By adopting the dandy roll being applied with so small depression to carry out embossing processing, small projection can be formed on the surface of sheet.Consequently, the sliding of sheet improves, and is easy to operation, the light scattering due to small projection in addition, and the white of sheet improves, and the inspection of therefore adhering to foreign matter etc. becomes easy.Small depression like this by after applying engraving to dandy roll surface, can be implemented known blasting treatment etc. and is easily formed.The degree of depth of small depression can add the particle size in man-hour according to sandblasting, pressure condition adjusts.

The embossing opposed roll 19 opposed with dandy roll, in order to improve the engraving on dandy roll surface to the transferability of operation sheet, and is preferably used in the roller that circumvolution in metallic roll has rubber.About the kind of rubber, be silicon rubber, nitrile rubber, neoprene etc., be not particularly limited, being preferably according to the A type hardness tester of JISK6253-2006 is the rubber of the scope of 65 ~ 85 °.Lower than 65 °, more than 85 °, then the transferability of embossed shapes reduces sometimes.In these rubber, silicon rubber is most preferred, because it is good with the release property being at high temperature easy to the operation sheet of adhering.

In embossing manufacturing procedure, make the operation sheet being supplied to dandy roll by annealing in process operation, the temperature on warmed-up surface is in the temperature range of (fusing point-10 DEG C forming the resin combination on this surface) ~ (forming the fusing point+20 DEG C of the resin combination on this surface).If be less than (fusing point of resin combination-10 DEG C), then the transferability of embossed shapes reduces.If exceeded (fusing point of resin combination+20 DEG C), then the temperature of the operation sheet in annealing operation is too high, is easy to fold etc. occurs in annealing operation.Such as, when the EVA resin that the layer of face side is 71 DEG C by fusing point is formed, the surface temperature that embossing adds man-hour is in the scope of 61 ~ 91 DEG C.

In addition, about the press pressure of dandy roll 20, the linear pressure that operation sheet is subject to is preferably the scope of 150 ~ 500N/cm.Be more preferably the scope of 200 ~ 450N/cm.If linear pressure is less than 150N/cm, then the transferability of embossed shapes reduces sometimes.If add the linear pressure more than 500N/cm, then need to make equipment enlarging, in this case, the life-span of opposed rubber rollers can reduce.

In prior art shown in Fig. 2, the press pressure of dandy roll 13b ', although high, linear pressure about 100N/cm is sufficient.Infer this is because, from the temperature of the resin that T-shaped die head is extruded, when being the EVA resin of 71 DEG C when such as using fusing point, mostly be the scope of 100 ~ 120 DEG C, owing to being the condition of high temperature, therefore for the transfer printing of embossed shapes, linear pressure about 100N/cm is sufficient.On the other hand, in manufacture method of the present invention, in the temperature range of (fusing point of resin combination-10 DEG C) ~ (fusing point of resin combination+20 DEG C), carry out embossing processing as mentioned above.Like this, if embossing adds the surface temperature step-down of the operation sheet in man-hour, then not easily transfer printing embossed shapes, therefore preferably improves the press pressure that embossing machining needs.That is, linear pressure is preferably made to be more than 150N/cm.In addition, linear pressure alleged in the present invention is the value pressing loading of roller obtained divided by the face length of roller.

In addition, in the embossing processing like this under relatively low temperature, in order to improve the transferability of embossed shapes, operation sheet is preferably made to embrace in dandy roll 20.Specifically, be preferably the scope of 30 ~ 270 ° to the attached angle of embracing of dandy roll.If only give shallow embossing, then embrace attached angle and can be less than 30 °, in order to give the embossing of shape deeply and clearly, preferably making to embrace attached angle is more than 30 °.In addition, embrace attached angle can be calculated by the length of circular arc of part and the ratio of the circumference of dandy roll that contact operation sheet 32 on dandy roll 20 simply.Such as, when to embrace an attached angle be 90 °, refer to the circumference with dandy roll 1/4 the suitable part contact operation sheet of length.

The surface temperature of the dandy roll 20 in this embossing manufacturing procedure is preferably (fusing point-20 DEG C forming the resin combination of the surface portion of the side of transfer printing embossed shapes) below.If the temperature of dandy roll is low, then the release property of operation sheet improves, and operation sheet is not easily wound on roller.Consequently, load when peeling off operation sheet from dandy roll is alleviated, and can obtain the better solar cell sealing sheet material of quality.

By operation sheet after the dandy roll demoulding, by chill roll 21 refrigerating work procedure sheet, the surface temperature of operation sheet is made promptly to be reduced near room temperature.

For by masking in this wise, annealing in process and remove heat shrink, and define the operation sheet 32 of embossed shapes, defect inspection, be desired width by the size adjusting of operation sheet after, by wound into rolls such as up-coilers, or cut into the section of desired length, and for the manufacture of solar module.

[solar cell sealing sheet material]

Next solar cell sealing sheet material is described.Seal stock is preferably the individual bumps that surface has height 60 ~ 300 μm.By having the projection of independently height more than 60 μm on the surface of seal stock, thus can manufacture solar module time vacuum lamination time, air residual between seal stock and solar battery cell is removed efficiently from multiple directions, suppresses the generation of bubble.In addition, seal stock can be made to disperse the pushing force of solar battery cell, suppress the generation that unit breaks.If the shape on seal stock surface is not individual bumps, but continuous print groove shape, then becoming insufficient perpendicular to degassed on the direction of groove, residual air becomes bubble.In addition, if the height of projection is less than 300 μm, then concentrated suppressed to the loading at top of projection during vacuum lamination, can prevent solar battery cell from breaking.Here, so-called " individual bumps ", be when being conceived to the bottom surface of projection, the length D on base described later is the projection of the scope of 70 ~ 6000 μm.

In addition, individual bumps is preferably, and is being clamped by seal stock flat board, and the pressure that through-thickness gives 50kPa carries out compressing and making bowing, when the top of projection expands with the dull and stereotyped region contacted, derive from 2 interregional gaps of guaranteeing 20 ~ 800 μm of 2 adjacent protrusions.

Individual bumps is preferably, and the height (T) of projection is 0.05 ~ 0.80 with the ratio (T/D) of the base length (D) of projection, is more preferably 0.15 ~ 0.80.If T/D ratio is less than 0.05, then the resiliency of seal stock becomes insufficient sometimes.If T/D ratio is more than 0.80, then projection produces the concentrated load at top, and generating unit breaks sometimes.The height T of projection measures as follows.First, illustrate a bossed situation of tool.The face of the bossed side of seal stock is set to A face, the face of unpolarized side is set to B face.As shown in Figure 3, the summit of the projection from A face is set to Tmax to the distance in B face, the distance from the unpolarized part in A face to B face is set to Tmin.The difference of this Tmax and Tmin is the height T of projection.The bossed situation of following explanation two side tool.Seal stock face is set to A face, another face is set to B face.As shown in Figure 4, the summit of the projection from A face is set to TAmax to the distance of the unpolarized part in B face, the summit of the projection from B face is set to TBmax to the distance of the unpolarized part in A face, the distance of the unpolarized part from the unpolarized part in A face to B face is set to Tmin.The difference of this TAmax and Tmin is the height TA of the projection in A face, and the difference of TBmax and Tmin is the height TB of the projection in B face.The length on the base of so-called projection is the outer circumference diameter D of the projection shown in Fig. 5.In addition, when the shape of the bottom surface of projection is the polygonal such as triangle, hexagon, ellipse, the length on the base of projection is the minimum true diameter of a circle of the shape comprising bottom surface.About above-mentioned Tmax, Tmin, D, can be measured by the observation of the sheet adopting stereomicroscope to carry out.

The height T of preferred projection is 60 ~ 300 μm as mentioned above.When the height T of projection is 60 μm, the length of the base D of projection is preferably 75 ~ 1200 μm, is more preferably 75 ~ 400 μm.When the height T of projection is 300 μm, the length of the base D of projection is preferably 375 ~ 6000 μm, is more preferably 375 ~ 2000 μm.

The number of individual bumps is preferably every 1cm ²the one-sided area of sheet is 40 ~ 2300.Be more preferably 40 ~ 1100.If individual bumps is less than 40/cm ², then sometimes generating unit break, bubble.If more than 2300/cm ², then above-mentioned T/D is than increasing, and due to the concentrated load to projecting tip, generating unit breaks sometimes.

The heat shrink rate of sheet flow direction that seal stock is preferably when to place 1 minute in the warm water of 80 DEG C is less than 30%.Be more preferably less than 25%.Here, " being placed in warm water ", little at the proportion of seal stock, when seal stock swims in the surface of warm water, be that seal stock is not sunk in warm water from upper pushing, place under the state that this is floating.On the other hand, great at the ratio of seal stock, when sinking in warm water under seal stock, be seal stock is not being supported from below, and place under the state of this sinking.In addition, so-called " sheet flow direction " is the direction of the operation sheet flowing in the manufacturing process of seal stock.In general vacuum lamination operation in the manufacture of solar module, during to seal stock fully melting, sheet pressurization is not vacuumized under state without load, carry out the melting of seal stock and degassed.Now, because the high temperature exposure at about 80 DEG C is in state without load, therefore there is the contraction of seal stock in seal stock, the breaking of result generating unit, misplaces.The present inventors are conceived to the breaking of unit, misplace and be studied, found that, when operation sheet being placed 1 minute under the state without load reproduced in vacuum lamination, the heat shrink rate as chankings flow direction is less than 30%, then can suppress breaking of unit further.The so-called state reproduced in this vacuum lamination is in the warm water of 80 °, place the state of operation sheet.In addition, the heat shrink rate in the direction orthogonal with the flow direction of sheet, than flow direction pettiness, is not particularly limited, but is preferably less than 5%.

The shape of individual bumps preferably hemispherical, the cone-shaped such as pyrometric cone, quadrangular pyramid, hexagonal cone, circular cone, make their top be flat trapezoidal shape.In addition, can for mixing the state having these shape for lugs.Wherein, hemispherical and/or corner taper is preferably.Here so-called " hemispherical and corner taper ", refer to that hemispheric projection mixes with the projection of corner taper the surface configuration existed.When pushing to solar battery cell, from not easily applying concentrated load to solar battery cell, and loading aspect can be disperseed equably to consider, preferably hemispherical.In addition, from the uneven of reverberation not easily occurs, the aspect that has excellent surface quality is considered, also preferred corner taper.And, in order to show these features that is hemispherical and corner taper, also preferably make hemispherically to mix with corner taper the shape existed.Deposit in case, as long as respective ratio at random determines according to more needing which kind of feature making hemispherical to mix with corner taper.It is all particularly preferably hemispheric pattern.

Seal stock of the present invention preferably has the projection of height 1 ~ 15 μm further in the face with individual bumps.By having so small projection, the sliding of sheet improves, and becomes and is easy to operation.In addition, the light scattering due to small projection, the white of sheet improves, and the inspection of therefore adhering to foreign matter etc. becomes easy.

Small projection like this can be realized by the manufacture method of the present invention implementing embossing processing after annealing operation.After implementing embossing processing, implemented in the method in the past of annealing in process by heating, sometimes highly for the large projection of several more than 10 μm also remains in sheet after a heating treatment, but highly for the small projection of about several μm disappears along with heat treatment.

In addition, the height of small projection is measure the numerical value obtained as follows.For the surface of sheet, according to JISB0601 (2001), use known laser microscope, such as Co., Ltd. キ ー エ Application ス laser microscope VK-X100 etc. take with multiplying power 400 sheet surface.In the roughness curve of the image of gained, Rz value when reaching cutoff 0.080mm is set to the height of small projection.

In the application, as the index of the resiliency evaluated for the seal stock that suppresses the unit of solar cell to break, adopt the resilience stress of sheet when bossed for the tool of a seal stock through-thickness being compressed 100 μm.The relation of the unit disruptiveness of solar cell and the resiliency of seal stock is conducted in-depth research, found that, the resilience stress broken of unit can be suppressed to be preferably below 70kPa.In addition, above-mentioned resilience stress obtains as follows: it is less than 5 μm that use has compression displacement, compression load is the compression test device of the resolving power of below 100Pa, measure flat pressurization terminal with the pressing speed of 0.02mm/s, to the tool of seal stock bossed through-thickness pressurize 100 μm time the resilience stress (kPa) of sheet, thus to obtain.If the resilience stress of seal stock is below 70kPa, then by make tool bossed mode contacted with solar battery cell carry out lamination, carries out vacuum lamination, thus breaking of solar battery cell can be suppressed.In addition, seal stock with the shape in the face of tool bossed opposition side, to be not particularly limited, but the adhesion etc. preventing seal stock when manufacturing from the viewpoint of solar module, preferably there is the small projection of height about 2 ~ 10 μm.

The thickness of seal stock is preferably 50 ~ 1500 μm.Be more preferably 100 ~ 1000 μm, be particularly preferably 200 ~ 800 μm.If be less than 50 μm, then the resiliency of solar cell sealing sheet material lacks sometimes, or has problems from the viewpoint of operability.If in addition more than 1500 μm, then the reduction of productive reduction, adaptation becomes problem sometimes.In addition, about the thickness of seal stock, under the one side only at seal stock forms bossed situation, it is the distance from the summit of projection to the face with tool bossed opposition side.Under the two sides of seal stock forms bossed situation, it is the distance on the summit of the projection from the summit of the projection in a face to opposing face.

Like this, in order to the surface at seal stock forms individual bumps exactly, or the heat shrink rate of seal stock is suppressed in specific scope, manufacture seal stock preferably by manufacture method of the present invention.

[forming the raw material of solar cell sealing sheet material]

Next the resin combination forming seal stock is described.In addition, the resin combination preferably at least forming the surface portion forming bossed side meets the composition etc. of the resin combination of following explanation.Certainly, the whole resin combination more preferably forming operation sheet meets the composition etc. of the resin combination of following explanation.

The resin combination forming seal stock preferably comprises polyolefin-based resins.As polyolefin-based resins, homo-polypropylene can be enumerated, with propylene be principal component with the polypropylene-based resin such as copolymer, ene-propylene-butene terpolymer of other monomer, low density polyethylene (LDPE), ultra-low density polyethylene, straight-chain low density polyethylene (LDPE), medium density polyethylene, high density polyethylene (HDPE), with ethene be principal component with polyethylene-based resin, the polyolefin thermoplastic elastomer (TPE)s etc. such as the copolymer of other monomer.As with ethene be principal component with the copolymer of other monomer, ethene-alpha-olefin copolymer, ethene-unsaturated monomer copolymer can be enumerated.As alpha-olefin, alpha-olefin can enumerate ethene, propylene, 1-butylene, isobutene, 1-amylene, 2-methyl-1-butene alkene, 3-methyl-1-butene, 1-hexene, 1-heptane, 1-octene, 1-nonene, 1-decene etc.As unsaturated monomer, vinyl acetate, acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate or vinyl alcohol etc. can be enumerated.In addition to these polyolefin-based resins, silane compound, carboxylic acid, glycidyl compound etc. is used to carry out a small amount of copolymerization as required or modification is one of preferred form.

In these polyolefin-based resins, from as the important transparency of solar cell sealing material, consider with the viewpoint such as the cementability of solar battery cell, the resin etc. preferably use vinyl-vinyl acetate copolymer, ethylene-methyl methacrylate methyl ester copolymer, obtaining the unsaturated silane compound modification of low density polyethylene (LDPE) olefinic.When using vinyl-vinyl acetate copolymer, ethylene-methyl acrylate copolymer, the content of copolymer composition is preferably the scope of 15 ~ 40 quality %.

In addition, the resin combination forming seal stock preferably comprises organic peroxide.Decompose as long as organic peroxide is the temperature more than 100 DEG C and produces the organic peroxide of free radical, then any organic peroxide can use, as long as consider temperature when manufacturing solar cell sealing sheet material, the storage stability etc. of heating binding temperature when making solar module and crosslinking agent itself carries out selecting.Particularly, the decomposition temperature of 10 hours preferred half-life is the organic peroxide of more than 70 DEG C.As the example of such organic peroxide, 1,1-bis-(tertiary hexyl peroxidating) cyclohexane can be enumerated, normal-butyl 4,4-bis--(tert-butyl hydroperoxide) valerate, 2,5-dimethyl-2,5-bis-(tert-butyl hydroperoxide) hexane, two-tert-butyl peroxide, two-tertiary hexyl peroxide, 2,5-dimethyl-2,5-bis-(tert-butyl hydroperoxide) hexin-3, disuccinic acid peroxide, two (4-tert-butylcyclohexyl) peroxy dicarbonate, 1,1,3,3-tetramethyl butyl peroxidating-2 ethyl hexanoic acid ester, tertiary hexyl peroxidating-2 ethyl hexanoic acid ester, tert-butyl hydroperoxide-2 ethyl hexanoic acid ester, tertiary hexyl isopropyl peroxide monocarbonate, two (4-tert-butylcyclohexyl) peroxy dicarbonate, tert-butyl hydroperoxide-3,5,5-tri-methyl hexanoic acid ester, tert-butyl hydroperoxide laurate, tert-butyl hydroperoxide-2-ethylhexyl monocarbonate, tert-butyl hydroperoxide-2 ethyl hexanoic acid ester, tert-butyl hydroperoxide isobutyrate, tert-butyl hydroperoxide acetic acid esters, the different pelargonate of tert-butyl hydroperoxide, t-amyl peroxy-2 ethyl hexanoic acid ester, t-amyl peroxy caprylic acid ester, the different pelargonate of t-amyl peroxy, t-amyl peroxy-2-ethylhexyl carbonate, two-t-amyl peroxy compound, 1,1-bis-(tert-butyl hydroperoxide) cyclohexane, ethyl 3,3-bis-(tert-butyl hydroperoxide) butyrate, 1,1-bis-(t-amyl peroxy) cyclohexane etc.These organic peroxides can combinationally use more than two kinds.The content of these organic peroxides is preferably 0.1 ~ 5 mass parts relative to polyolefin-based resins 100 mass parts.Be more preferably 0.1 ~ 3 mass parts, be particularly preferably 0.2 ~ 2 mass parts.If the content of organic peroxide is less than 0.1 mass parts, then polyolefin-based resins sometimes can not be made to be cross-linked.Even if contain more than 5 mass parts, except this containing effective low except, undecomposed organic peroxide remains in seal stock, has the possibility of reason becoming deterioration year in year out.

The resin combination forming seal stock can comprise crosslinking coagent, silane series coupling agent, light stabilizer, ultra-violet absorber, antioxidant etc. further.

Crosslinking coagent is the multi-functional monomer in molecule with multiple unsaturated bond, being and the decomposition by organic peroxide and the living radical compound that produces reacts, using to make polyolefin-based resins evenly and efficiently crosslinked.As the example of these crosslinking coagents, isocyanuric acid triallyl ester can be enumerated, cyanuric acid alkatriene propyl diester, trimethylolpropane tris (methyl) acrylate, pentaerythrite three (methyl) acrylate, three ［ (methyl) acryloyl-oxyethyl ］ isocyanuric acid ester, dihydroxy methylpropane four (methyl) acrylate, pentaerythrite four (methyl) acrylate, pentaerythrite ethyoxyl four (methyl) acrylate, dipentaerythritol five (methyl) acrylate, dipentaerythritol six (methyl) acrylate, divinylbenzene etc.These crosslinking coagents can individually use, and also can two or more also use.In addition, in the present invention, " (methyl) acrylate " refers to " acrylate or methacrylate ".

In these crosslinking coagents, be particularly preferably isocyanuric acid triallyl ester, trimethylolpropane tris (methyl) acrylate.Content when adding these crosslinking coagents is, is preferably 0 ~ 5 mass parts relative to polyolefin-based resins 100 mass parts.Be more preferably 0.1 ~ 3 mass parts, be particularly preferably 0.3 ~ 3 mass parts.Even if contain more than 5 mass parts, the raising of effect is also very little, becomes cost increase factor.

Silane series coupling agent preferably uses to improve the cementability of the various component such as solar cell sealing sheet material and solar battery cell, backboard, glass.Content when adding silane series coupling agent is, relative to polyolefin-based resins 100 mass parts, is preferably the scope of 0.05 ~ 2 mass parts.If be less than 0.05 mass parts, then containing effective low.Even if contain more than 2 mass parts, the raising effect of cementability is also low.As silane series coupling agent, be not particularly limited, the alkoxysilane compound containing trialkylsilyl group in molecular structure being such as selected from least a kind of functional group had in methacryloxy, acryloxy, epoxy radicals, sulfydryl, urea groups, NCO, amino, hydroxyl can be enumerated.As its concrete example, γ-methacryloyloxypropyl methyl dimethoxysilane can be enumerated, γ-methacryloxypropyl trimethoxy silane, γ-methacryloyloxypropyl methyl diethoxy silane, the alkoxysilane compound containing trialkylsilyl group in molecular structure containing methacryloxy such as γ-methacryloxypropyl trimethoxy silane, the alkoxysilane compound containing trialkylsilyl group in molecular structure containing acryloxy such as γ-acryloxypropyl trimethoxy silane, γ-glycidoxypropyltrime,hoxysilane, γ-glycidoxypropyl group triethoxysilane, the alkoxysilane compound containing trialkylsilyl group in molecular structure containing epoxy radicals such as β-(3,4-epoxycyclohexyl) ethyl trimethoxy silane, γ mercaptopropyitrimethoxy silane, the alkoxysilane compound containing trialkylsilyl group in molecular structure containing sulfydryl such as γ-Mercaptopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, the alkoxysilane compound containing trialkylsilyl group in molecular structure containing urea groups such as γ-ureido-propyl trimethoxy silane, γ-NCO propyl-triethoxysilicane, γ-NCO propyl trimethoxy silicane, the alkoxysilane compound containing trialkylsilyl group in molecular structure containing NCO such as γ-NCO hydroxypropyl methyl dimethoxysilane, γ-(2-amino-ethyl) amino propyl methyl dimethoxysilane, γ-(2-amino-ethyl) TSL 8330, gamma-amino propyl trimethoxy silicanes etc. are containing amino alkoxysilane compound containing trialkylsilyl group in molecular structure, γ-hydroxypropyl trimethoxy silane, the alkoxysilane compound containing trialkylsilyl group in molecular structure etc. containing hydroxyl such as γ-hydroxypropyl triethoxysilane.Wherein, from the viewpoint of the compatibility with polyolefin-based resins, be preferably the alkoxysilane compound containing trialkylsilyl group in molecular structure containing methacryloxy, more preferably γ-methacryloxypropyl trimethoxy silane.

The resin combination forming seal stock preferably comprises ultra-violet absorber further.Ultra-violet absorber absorbs the harmful UV rays irradiated in light, is transformed into harmless heat energy in molecule, prevents the material of the spike exciting the light deterioration caused in macromolecule.As ultra-violet absorber, known material can be used.Can use such as, benzophenone series, BTA system, triazine system, salicylic acid system, cyanoacrylate system etc.1 kind in them can be used, also can two or more combinationally use.

As benzophenone series ultra-violet absorber, can enumerate such as, 2, 2 '-dihydroxy-4, 4 '-two (hydroxymethyl) benzophenone, 2, 2 '-dihydroxy-4, 4 '-two (2-hydroxyethyl) benzophenone, 2, 2 '-dihydroxy-3, 3 '-dimethoxy-5, 5 '-two (hydroxymethyl) benzophenone, 2, 2 '-dihydroxy-3, 3 '-dimethoxy-5, 5 '-two (2-hydroxyethyl) benzophenone, 2, 2 '-dihydroxy-3, 3 '-two (hydroxymethyl)-5, 5 '-dimethoxy-benzophenone, 2, 2 '-dihydroxy-3, 3 '-two (2-hydroxyethyl)-5, 5 '-dimethoxy-benzophenone, 2, 2-dihydroxy-4, 4-dimethoxy-benzophenone etc.

As BTA system ultra-violet absorber, can enumerate such as, 2-(2 '-hydroxyl-5 '-(hydroxymethyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-5 '-(2-hydroxyethyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-5 '-(3-hydroxypropyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-3 '-methyl-5 '-(hydroxymethyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-3 '-methyl-5 '-(2-hydroxyethyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-3 '-methyl-5 '-(3-hydroxypropyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-3 '-the tert-butyl group-5 '-(hydroxymethyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-3 '-the tert-butyl group-5 '-(2-hydroxyethyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-3 '-tertiary octyl group-5 '-(hydroxymethyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-3 '-tertiary octyl group-5 '-(2-hydroxyethyl) phenyl)-2H-BTA, 2-(2 '-hydroxyl-3 '-tertiary octyl group-5 '-(3-hydroxypropyl) phenyl)-2H-BTA etc., or 2, 2 '-di-2-ethylhexylphosphine oxide (6-(2H-BTA-2-base)-4-(hydroxymethyl) phenol), 2, 2 '-di-2-ethylhexylphosphine oxide (6-(2H-BTA-2-base)-4-(2-hydroxyethyl) phenol), 2, 2 '-di-2-ethylhexylphosphine oxide (6-(2H-BTA-2-base)-4-(3-hydroxypropyl) phenol), 2, 2 '-di-2-ethylhexylphosphine oxide (6-(2H-BTA-2-base)-4-(4-hydroxybutyl) phenol), 3, 3-{ 2, 2 '-bis-(6-(2H-BTA-2-base)-1-hydroxyl-4-(2-hydroxyethyl) phenyl) } propane, 2, 2-{ 2, 2 '-bis-(6-(2H-BTA-2-base)-1-hydroxyl-4-(2-hydroxyethyl) phenyl) } butane, 2, 2 '-oxygen base two (6-(2H-BTA-2-base)-4-(2-hydroxyethyl) phenol), 2, 2 '-bis-(6-(2H-BTA-2-base)-4-(2-hydroxyethyl) phenol) amine etc.

As triazine system ultra-violet absorber, can enumerate such as, 2-(2-hydroxy-4-hydroxymethyl yhnethylphenyl)-4, 6-diphenyl-s-triazine, 2-(2-hydroxy-4-hydroxymethyl yhnethylphenyl)-4, 6-two (2, 4-3,5-dimethylphenyl)-s-triazine, 2-(2-hydroxyl-4-(2-hydroxyethyl) phenyl)-4, 6-diphenyl-s-triazine, 2-(2-hydroxyl-4-(2-hydroxyethyl) phenyl)-4, 6-two (2, 4-3,5-dimethylphenyl)-s-triazine, 2-(2-hydroxyl-4-(2-hydroxyl-oxethyl) phenyl)-4, 6-diphenyl-s-triazine, 2-(2-hydroxyl-4-(2-hydroxyl-oxethyl) phenyl)-4, 6-two (2, 4-3,5-dimethylphenyl)-s-triazine, 2-(2-hydroxyl-4-(3-hydroxy propyloxy group) phenyl)-4, 6-diphenyl-s-triazine, 2-(2-hydroxyl-4-(3-hydroxy propyloxy group) phenyl)-4, 6-two (2, 4-3,5-dimethylphenyl)-s-triazine, 2-(2-hydroxyl-4-(4-hydroxybutyl) phenyl)-4, 6-diphenyl-s-triazine, 2-(2-hydroxyl-4-(4-hydroxybutyl) phenyl)-4, 6-two (2, 4-3,5-dimethylphenyl)-s-triazine, 2-(2-hydroxyl-4-(4-hydroxybutoxy) phenyl)-4, 6-diphenyl-s-triazine, 2-(2-hydroxyl-4-(4-hydroxybutoxy) phenyl)-4, 6-two (2, 4-3,5-dimethylphenyl)-s-triazine, 2-(2-hydroxy-4-hydroxymethyl yhnethylphenyl)-4, two (2-hydroxy-4-methyl the phenyl)-s-triazine of 6-, 2-(2-hydroxyl-4-(2-hydroxyethyl) phenyl)-4, two (2-hydroxy-4-methyl the phenyl)-s-triazine of 6-, 2-(2-hydroxyl-4-(2-hydroxyl-oxethyl) phenyl)-4, two (2-hydroxy-4-methyl the phenyl)-s-triazine of 6-, 2-(2-hydroxyl-4-(3-hydroxypropyl) phenyl)-4, two (2-hydroxy-4-methyl the phenyl)-s-triazine of 6-, 2-(2-hydroxyl-4-(3-hydroxy propyloxy group) phenyl)-4, two (2-hydroxy-4-methyl phenyl)-s-triazine of 6-etc.

As salicylic acid system ultra-violet absorber, phenyl salicytate can be enumerated, to tert-butylphenyl salicylate acid esters, OPS p octylphenyl salicylate etc.

As cyanoacrylate system ultra-violet absorber, 2-ethylhexyl-2-cyano group-3,3 '-diphenylacrylate ester, ethyl-2-cyano group-3,3 '-diphenylacrylate ester etc. can be enumerated.

In these ultra-violet absorbers, painted from the viewpoint of ultraviolet radiation absorption effect and ultra-violet absorber itself, most preferably is the ultra-violet absorber of benzophenone series.

When adding above-mentioned ultra-violet absorber, relative to polyolefin-based resins 100 mass parts, be preferably 0.05 ~ 3 mass parts.Be more preferably 0.05 ~ 2.0 mass parts.If content is less than 0.05 mass parts, then containing effective low, if more than 3 mass parts, then tend to painted.

The resin combination forming seal stock preferably comprises light stabilizer further.Light stabilizer is, supplements the free radical kind harmful to polymer, does not produce the material of new free radical.As light stabilizer, preferably use hindered amine system light stabilizer.

As hindered amine system light stabilizer, decanedioic acid two (2 can be enumerated, 2, 6, 6-tetramethyl-1 (octyl group oxygen base)-4-piperidyl) ester, by 1, the mixture that the reaction product 70 quality % of 1-dimethyl ethyl hydroperoxides and octane and polypropylene 30 quality % is formed, two (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) ［ ［ 3, 5-two (1, 1-dimethyl ethyl)-4-hydroxy phenyl ］ methyl ］ butylmalonic acid ester, two (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) sebacate and methyl isophthalic acid, 2, 2, 6, 6-pentamethyl-4-piperidinyl sebacate mixture, two (2, 2, 6, 6-tetramethyl-4-piperidyl) sebacate, four (2, 2, 6, 6-tetramethyl-4-piperidyl)-1, 2, 3, 4-butane tetracarboxylic acid esters, four (1, 2, 2, 6, 6-pentamethyl-4-piperidyl)-1, 2, 3, 4-butane tetracarboxylic acid esters, 2, 2, 6, 6-tetramethyl-4-piperidyl-1, 2, 3, 4-butane tetracarboxylic acid esters and tridecyl-1, 2, 3, the mixture of 4-butane tetracarboxylic acid esters, 1, 2, 2, 6, 6-pentamethyl-4-piperidyl-1, 2, 3, 4-butane tetracarboxylic acid esters and tridecyl-1, 2, 3, the mixture of 4-butane tetracarboxylic acid esters, poly-［ { 6-(1, 1, 3, 3-tetramethyl butyl) amino-1, 3, 5-triazine-2, 4-bis-base } { (2, 2, 6, 6-tetramethyl-4-piperidyl) imino group } hexa-methylene { (2, 2, 6, 6-tetramethyl-4-piperidyl) imino group }, dimethyl succinate and 4-hydroxyl-2, 2, 6, the polymer of 6-tetramethyl-1-piperidine ethanol, N, N ', N ' ', N ' ' '-four-(4, 6-pair-(butyl-(N-methyl-2, 2, 6, 6-tetramethyl piperidine-4-base) amino)-triazine-2-base)-4, 7-diaza decane-1, 10-diamines and above-mentioned dimethyl succinate and 4-hydroxyl-2, 2, 6, the mixture of the polymer of 6-tetramethyl-1-piperidine ethanol, dibutylamine 1, 3, 5-triazine N, N '-bis-(2, 2, 6, 6-tetramethyl-4-piperidyl-1, 6-hexamethylene diamine and N-(2, 2, 6, 6-tetramethyl-4-piperidyl) condensation polymer etc. of butylamine.Above-mentioned hindered amine system light stabilizer can be used alone one, also can more than two kinds used in combination.

Wherein, as hindered amine system light stabilizer, preferably use two (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl isophthalic acid, 2,2,6, the mixture of 6-pentamethyl-4-piperidinyl sebacate and methyl-4-piperidinyl sebacate, two (2,2,6,6-tetramethyl-4-piperidyl) sebacate.In addition, hindered amine system light stabilizer preferably uses fusing point to be the hindered amine system light stabilizer of more than 60 DEG C.

Content when adding hindered amine system light stabilizer is preferably 0.05 ~ 3.0 mass parts relative to polyolefin-based resins 100 mass parts.Be more preferably 0.05 ~ 1.0 mass parts.If content is less than 0.05 mass parts, then stabilization effect is insufficient, even if contain more than 3.0 mass parts, also can become factor that is painted, cost increase.

In addition, in the scope not encumbering effect of the present invention, as known additive, antioxidant, fire retardant, flame retardant, plasticizer, lubricant, colouring agent etc. can be contained as required.

[solar module]

The formation of solar module is containing sensitive surface guard member, back-protective part, is configured between this sensitive surface protective agent and back-protective part and is sealed with the layer of solar battery cell by seal stock.As seal stock used herein, the seal stock obtained by manufacture method of the present invention can be used, also can use the above-mentioned seal stock on surface with individual bumps.

The seal stock obtained by manufacture method of the present invention, by little for the heat shrink during integration of the material laminate of above-mentioned formation.Therefore, residual stress during shaping between solar battery cell and seal stock, between sensitive surface guard member and seal stock, between back-protective part and seal stock is little, becomes the solar module of long-term excellent in te pins of durability.

In addition, the above-mentioned seal stock on surface with individual bumps, owing to can make the pushing force to solar battery cell during the integration of the material laminate of above-mentioned formation to be disperseed, the residual stress therefore between solar battery cell and seal stock can reduce.In addition, also not entrapped air pockets in seal.Therefore, the solar module of long-term excellent in te pins of durability is become.

Embodiment

Below show the determination method used in the present embodiment.As long as no specializing, measuring n number is 5, adopts mean value.

(1) thickness of sheet

For the seal stock molded, measure the thickness of arbitrary 20 at width, obtain average thickness.Analyzer employs ミ Star ト ヨ society's calibrator (547-301 type).About the thickness of seal stock, under the one side only at seal stock forms bossed situation, measure the distance from the summit of projection to the face with tool bossed opposition side.Under the two sides of seal stock forms bossed situation, measure the distance on the summit of the projection from the summit of the projection in a face to opposing face.

(2) rising height

In the direction (width) at a right angle with the moving direction (hreinafter referred to as MD direction) of sheet when manufacturing, cut off seal stock in the mode at the top by projection.The thickness direction cross section stereomicroscope of the seal stock cut off is observed at whole width of sheet.

In a bossed situation of tool of seal stock, the face of the bossed side of seal stock is set to A face, the face of unpolarized side is set to B face.As shown in Figure 3, the summit of the projection from A face is set to Tmax to the distance in B face, the distance from the unpolarized part in A face to B face is set to Tmin.Then, the height T of projection is calculated by formula (i).

·T(μm)＝Tmax－Tmin···(i)

In the bossed situation of two sides tool of seal stock, seal stock face is set to A face, another face is set to B face.As shown in Figure 4, the summit of the projection from A face is set to TAmax to the distance of the unpolarized part in B face, the summit of the projection from B face is set to TBmax to the distance of the unpolarized part in A face, the distance of the unpolarized part from the unpolarized part in A face to B face is set to Tmin.Then, calculated the height TA of the projection in A face by formula (ii), calculated the height TB of the projection in B face by formula (iii).

·TA(μm)＝TAmax－Tmin···(ii)

·TB(μm)＝TBmax－Tmin···(iii)。

(3) depth of pattern of dandy roll

For the surface of dandy roll, according to JISB0601 (2001), measure under the condition determination of datum length 20mm, loading 0.75mN, finding speed 0.3mm/s.Measure and use the small-sized roughness tester SJ401 of ミ Star ト ヨ society's system, the diamond stylus of use 60 °, circular cone, front end radius of curvature 2 μm measures.This measured value is set to the depth of pattern Pz value (μm) of dandy roll.

(4) embossing transferring rate

The value that the rising height T (μm) (or rising height TA (μm) or rising height TB (μm)) measured in above-mentioned (2) obtains divided by the depth of pattern Pz of the dandy roll measured in above-mentioned (3) is set to embossing transferring rate.

Embossing transferring rate (%)=T/Pz × 100.

(5) heat shrink rate

Cut out while be the test film of plane square shape of 120mm from seal stock.On this test film, TD direction central portion during fabrication, vacates the interval of 100mm and draws the straight line (5cm) in two parallel TD directions.And, at position (each 5 places) marking by each straight line 6 decile.

Next, by test film be heated in the warm water of 80 DEG C place 60 seconds.Little at the proportion of seal stock, when seal stock swims in warm water surface, place under the state that this is floating.Great at the ratio of seal stock, when seal stock sinks in warm water, place under the state of this sinking.After 60 seconds, test film is taken out from warm water, flood 10 seconds in the normal-temperature water of 20 DEG C and after cooling, remove the moisture on sheet surface.

The interval A (mm) of opposed each mark done by measuring from each mark of 5 done by the straight line of drawing at test film to another straight line with vernier, calculates heat shrink rate based on following formula, obtains the mean value at 5 places.

Heat shrink rate (%)=(100-A)/100 × 100.

(6) melt flow rate (MFR) of the resin combination of seal stock is formed

For resin combination, according to JISK7210 (1999) " melt mass flow rate (MFR) of plastics-thermoplastic and the test method of melt volume-flow rate (MVR) ", measure under the experimental condition of temperature 190 DEG C, load 2.16kg.

(7) the base length (D) of projection

Bossed for the tool of sheet is observed with stereomicroscope, measures base length (D).When the shape of the bottom surface of projection is the polygonal such as triangle, hexagon, ellipse, measure the minimum true diameter of a circle comprising above-mentioned shape.

(8) unit disruptiveness

2 are cut out while be the test film of the plane square shape of 180mm from seal stock.At the upper soldering interconnector (thickness 280 μm, width 2mm) of many crystalline solar cells unit (3 busbars, size 156mm is square, thickness 200 μm), make the solar battery cell with interconnector.Prepare glass plate (size 180mm is square, thickness 3mm) and polyester solar cell backboard (size 180mm is square, thickness 240 μm).Lamination seal stock, solar battery cell, seal stock, backboard successively on a glass.Now, bossed of the tool of seal stock and solar battery cell carry out lamination contiguously.For this laminated body, temperature 145 DEG C, vacuumize 30 seconds, compacting 1 minute, pressure carries out vacuum lamination under keeping the condition of 10 minutes, makes solar module.For the solar module of gained, by solar cell EL image testing device, shooting luminescent image, determination unit breaks the length (mm) of total crackle in portion.This test is repeated 3 times, obtains the mean value of total crack length.

(9) bubble number

By the bubble number in the solar module of making in visual counting above-mentioned (8).Obtain the mean value of 3 tests.

(10) resilience stress

Cut out while be the test film of plane square shape of 120mm from seal stock.Then, use カ ト ー テ ッ Network society compression test KESFB-3, from bossed of the tool of test film, by the flat pressurization terminal of diameter 16mm with speed 20 μm/second to seal stock pressurization, measure through-thickness pressurize 100 μm time the resilience stress (kPa) of sheet.This test is repeated 3 times, obtains the mean value of resilience stress.

(embodiment 1)

According to the manufacture method shown in Fig. 1, make solar cell sealing sheet material

Operation (a): film making process

Double screw extruder is used as extruder 11, will containing EVA (vinyl acetate content: 28 quality %, melt flow rate (MFR): 15g/10 minute, fusing point: 71 DEG C) 100 mass parts, tert-butyl hydroperoxide-2-ethylhexyl monocarbonate (1 hr half-life temperature: 119 DEG C) 0.7 mass parts, isocyanuric acid triallyl ester 0.3 mass parts, γ-methacryloxypropyl trimethoxy silane 0.2 mass parts, ESCALOL 567 0.3 mass parts, two (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) resin combination of sebacate 0.1 mass parts is supplied to the extruder 11 that is set as 80 DEG C and carries out melting mixing.Resin combination after mixing is extruded from the T-shaped die head 12 being held in 105 DEG C be connected with extruder 11.The die lip width of T-shaped die head used in addition is 1300mm, and die lip gap is 0.8mm.

By the resin combination extruded like this by being held in polishing roll 13a, 13b, 13c of 20 DEG C and cooling curing, make sheet.In addition, from the temperature of the operation sheet in the moment that T-shaped die head is discharged be 107 DEG C.In addition the width of operation sheet is now 1150mm, and thickness is 450 μm, and transporting velocity is 10m/ minute.

Operation (b): annealing in process operation

Next, annealing in process is implemented under the condition described in table 1.

About heating, use ceramic heater 16, conveying roller 17 uses with the distance between centers of roller as the interval that 200mm is such arranges diameter 150mm and is coated with the conveying roller of the metallic roll of " teflon (registration mark) " on surface.Annealing furnace 15 employs the annealing furnace of heat-insulating material that to have reeled on the housing of SUS.In addition, from entrance bottom and the outlet bottom of annealing furnace 15, hot blast is blown into wind speed 1m/sec.

Operation (c): embossing manufacturing procedure

According to the condition described in table 1, implement embossing continuously with annealing in process and process.

Embossing processing is following to be implemented: by the operation sheet transferred out from annealing furnace by depth of pattern be 120 μm dandy roll 20 and be wound with thickness 10mm hardness 75 ° silicon rubber embossing opposed roll 19 between.

Evaluate heat shrink rate and the embossing transferring rate of the solar cell sealing sheet material of gained.Show the result in table 1.As shown in table 1, obtain heat shrink rate very little, and clearly transferred with the solar cell sealing sheet material of pattern of indentations.

(embodiment 2)

The temperature of the hot blast in operation (b) is set to 87 DEG C, heter temperature is set to 320 DEG C, the holdup time in stove is set to 29 seconds, in addition, by making seal stock with embodiment 1 same procedure.Because the surface temperature of operation sheet reduces, therefore heat shrink rate becomes large a little, in addition embossing transferring rate step-down a little, but it is very little to obtain heat shrink rate similarly to Example 1, and clearly transferred with the solar cell sealing sheet material of pattern of indentations.

(embodiment 3)

The temperature of the hot blast in operation (b) is set to 80 DEG C, heter temperature is set to 300 DEG C, the holdup time in stove is set to 30 seconds, linear pressure is set to 450N/cm, in addition, by making seal stock with embodiment 1 same procedure.Because the surface temperature of operation sheet reduces further, therefore heat shrink rate becomes large a little, in addition embossing transferring rate step-down a little, but it is very little to obtain heat shrink rate similarly to Example 1, and clearly transferred with the solar cell sealing sheet material of pattern of indentations.

(embodiment 4)

Linear pressure in operation (c) is set to 200N/cm, in addition, by making seal stock with embodiment 3 same procedure.Embossing transferring rate step-down a little, but obtain similarly to Example 3 clearly transferred with the solar cell sealing sheet material of pattern of indentations.

(embodiment 5)

Hot blast temperature in operation (b) is set to 110 DEG C, the holdup time in stove is set to 27 seconds, the linear pressure in operation (c) is set to 200N/cm, in addition, make sheet by method similarly to Example 1.The surface temperature of operation sheet raises, and therefore obtains heat shrink rate very little, embossing transferring rate also solar cell sealing sheet material clearly.

(embodiment 6)

By in operation (c) to dandy roll embrace an attached angle be set to 45 °, in addition, by making seal stock with embodiment 5 same procedure.Diminish owing to embracing an attached angle, thus embossing transferring rate is some diminishes, but for having the sheet of good outward appearance.

(embodiment 7)

The transporting velocity of the operation sheet in operation (b) is set to 7m/min, hot blast temperature is set to 110 DEG C, heter temperature is set to 300 DEG C, holdup time in stove is set to 39 seconds, linear pressure in operation (c) is set to 120N/cm, in addition, seal stock is made by method similarly to Example 1.The heat time of operation sheet is elongated, and surface temperature uprises, and therefore can make heat shrink rate and significantly reduce, even if the sheet of the low also embossed shapes clearly of linear pressure.

(comparative example 1 ~ 5)

Condition shown in application table 2, in addition, makes solar cell sealing sheet material by method similarly to Example 1.

(comparative example 6,7)

After just extruding from T-shaped die head, implement embossing processing by the manufacture method in the past shown in Fig. 2, then carry out annealing in process.Annealing in process device is device similarly to Example 1, and the tight dandy roll 13b ' below of T-shaped die head uses depth of pattern to be the roller of 120 μm.

[table 1]

[table 2]

(result)

As shown in table 1, the solar cell sealing sheet material be made up of embodiment 1 ~ 7, heat shrink rate is little, and embossing transferring rate is high, lucidly transferred with embossed shapes.

Use these solar cell sealing sheet materials, make solar module by known method, result is when module is made, and unit misplaces, or unit breaks, or bubble is mixed into such undesirable condition and does not occur.

In comparative example 1, because the sheet temperature of temperature during annealing in process, dandy roll 20 entrance is all low, be therefore that heat shrink rate is also large, the sheet that embossing transferring rate is also low.In comparative example 3, owing to expanding the interval between annealing furnace outlet and dandy roll entrance, therefore the temperature of sheet reduces, and embossing transferring rate reduces.In comparative example 4, because the sheet surface temperature in annealing furnace is low, therefore can not fully reduce heat shrink rate.

In comparative example 2, on dandy roll, circumvolution operation sheet, can not obtain sample.

In comparative example 5, because the annealing in process time is short, the heat shrink of solar cell sealing sheet material therefore fully can not be reduced.

In comparative example 6,7, owing to giving embossed shapes with polishing roll, therefore embossed shapes is unclear, if but heat shrink will be made to reduce, then embossed shapes collapse, if will keep embossed shapes, then can not reduce heat shrink.

(embodiment 8)

Operation (a): film making process

Will containing EVA (vinyl acetate content: 28 quality %, melt flow rate (MFR): 15g/10 minute (190 DEG C), fusing point: 71 DEG C) 100 mass parts, tert-butyl hydroperoxide-2-ethylhexyl monocarbonate (1 hr half-life temperature: 119 DEG C) 0.7 mass parts, isocyanuric acid triallyl ester 0.3 mass parts, γ-methacryloxypropyl trimethoxy silane 0.2 mass parts, ESCALOL 567 0.3 mass parts, two (1, 2, 2, 6, 6-pentamethyl-4-piperidyl) resin combination of sebacate 0.1 mass parts is supplied to the double screw extruder melting mixing that are set as 80 DEG C.Resin combination after mixing is extruded from the T-shaped die head being held in 105 DEG C be connected with double screw extruder.The die lip width of T-shaped die head is 1300mm in addition, and die lip gap is 0.8mm.

By this EVA sheet by being held in the polishing roll of 20 DEG C and cooling curing.In addition, the sheet temperature in moment that EVA sheet is discharged from T-shaped die head is 107 DEG C.In addition sheet width is now 1150mm, and the thickness of sheet is 450 μm, and sheet transporting velocity is 10m/ minute.Next, annealing in process, embossing processing is implemented continuously.

Operation (b): annealing in process operation

Annealing in process is carried out as follows: arrange ceramic heater surface temperature being set as 350 DEG C, for the interval that 250mm is such with the distance between centers of roller diameter 150mm be set and be coated with the metallic roll of " teflon (registration mark) " on surface, passing through in the annealing furnace that the housing of SUS is wound with heat-insulating material.In addition, from entrance bottom and the outlet bottom of stove, hot blast is blown into wind speed 1m/sec.

Operation (c): embossing manufacturing procedure

Embossing processing is following to be implemented: by the sheet taken out from annealing furnace, with 450/cm ²have that depth of pattern is 180 μm, diameter 460 μm and the dandy roll of the depiction of the matrix of semi-spherical shape and be wound with thickness 10mm hardness 75 ° silicon rubber opposed roll between pass through.

In addition, above-mentioned manufacturing condition is as follows in detail.

The sheet surface temperature of annealing furnace entrance: 23 DEG C

Hot blast temperature: 93 DEG C

The maximum temperature on the sheet surface in annealing furnace: 90 DEG C

The sheet surface temperature of annealing furnace outlet: 90 DEG C

The sheet holdup time in annealing furnace: 28 seconds

The sheet speed that annealing furnace 15 exports: 9.6m/min

The sheet surface temperature of dandy roll entrance: 78 DEG C

Dandy roll temperature: 15 DEG C

The linear pressure of dandy roll: 350N/cm

Armful attached angle to dandy roll: 120 °.

Evaluate unit disruptiveness, bubble number during heat shrink rate and resilience stress, the modular manufacture of the seal stock of gained.Show the result in table 3.As shown in table 3, be that sheet heat shrink rate is little, the seal stock that unit during modular manufacture breaks, bubble is few.

(embodiment 9)

Dandy roll in operation (c) is changed to 450/cm ²having depth of pattern is 120 μm, diameter 460 μm and the dandy roll of the depiction of the matrix of semi-spherical shape, in addition, makes seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 3, is that sheet heat shrink rate is little, the seal stock that unit during modular manufacture breaks, bubble is few.

(embodiment 10)

Dandy roll in operation (c) is changed to 450/cm ²having depth of pattern is 300 μm, diameter 460 μm and the dandy roll of the depiction of the matrix of semi-spherical shape, in addition, makes seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 3, is that sheet heat shrink rate is little, the seal stock that unit during modular manufacture breaks, bubble is few.

(embodiment 11)

Dandy roll in operation (c) is changed to 980/cm ²having depth of pattern is 300 μm, diameter 330 μm and the dandy roll of the depiction of the matrix of semi-spherical shape, in addition, makes seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 3, is that sheet heat shrink rate is little, the seal stock that unit during modular manufacture breaks, bubble is few.

(embodiment 12)

Dandy roll in operation (c) is changed to 840/cm ²having depth of pattern is 180 μm, outer circumference diameter 460 μm and the dandy roll of the depiction of the matrix of quadrangle cone shape, in addition, makes seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 3, some generations although unit during modular manufacture breaks, and is the seal stock that sheet heat shrink rate is little, bubble is few.

(embodiment 13)

Do not implement annealing in process, by infrared heater, sheet surface temperature is heated to 90 DEG C, implement embossing processing, in addition, make seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 3, although the heat shrink rate of sheet is large, unit during modular manufacture breaks some generations, is the seal stock that bubble is few.

(embodiment 14)

EVA resin is changed to the EVA resin of melt flow rate (MFR) 10g/10 minute, in addition, make seal stock by method similarly to Example 8.The seal stock of gained is as shown in table 3, some generations although unit during modular manufacture breaks, and is the seal stock that sheet heat shrink rate is little, bubble is few.

(embodiment 15)

Dandy roll in operation (c) is changed to 45/cm ²having depth of pattern is 180 μm, outer circumference diameter 2000 μm and the dandy roll of the depiction of the matrix of quadrangle cone shape, in addition, makes seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 3, although sheet heat shrink rate is little, unit during modular manufacture breaks some generations, is the seal stock that bubble is few.

(reference example 1)

Unreal line processing of exerting pressure, in addition, is made by method similarly to Example 8 and implements until the seal stock of annealing in process, for evaluation.

The seal stock of gained is as shown in table 4, although the heat shrink rate of sheet is little, for unit during modular manufacture breaks, and a large amount of seal stock producing bubble.

(reference example 2)

Dandy roll in operation (c) is changed to depth of pattern and be 180 μm and the dandy roll in the direction of rotation of roller with the depiction of the groove (groove width 460 μm) of continuous print semi-circular shape, in addition, seal stock is made by method similarly to Example 8.

The seal stock of gained is as shown in table 4, although sheet heat shrink rate is little, unit during modular manufacture breaks few, is the seal stock that bubble is many.

(reference example 3)

Dandy roll in operation (c) is changed to 450/cm ²having depth of pattern is 50 μm, diameter 460 μm and the dandy roll of the depiction of the matrix of semi-spherical shape, in addition, makes seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 4, although sheet heat shrink rate is little, is the seal stock that unit breaks, bubble is many during modular manufacture.

(reference example 4)

Dandy roll in operation (c) is changed to 4500/cm ²having depth of pattern is 180 μm, diameter 150 μm and the dandy roll of the depiction of the matrix of semi-spherical shape, in addition, makes seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 4, although sheet heat shrink rate is little, bubble is few, the seal stock more than unit when being modular manufacture breaks.

(reference example 5)

Dandy roll in operation (c) is changed to 7/cm ²having depth of pattern is 180 μm, diameter 3800 μm and the dandy roll of the depiction of the matrix of semi-spherical shape, in addition, makes seal stock by method similarly to Example 8.

The seal stock of gained is as shown in table 4, although sheet heat shrink rate is little, is the seal stock that unit during modular manufacture breaks and bubble is many.

[table 3]

[table 4]

Industry utilizability

The present invention can be suitable for the manufacture method of solar cell sealing sheet material very much.Particularly, owing to reducing heat shrink, there is pattern of indentations clearly, the position skew of unit when therefore can prevent modular manufacture, the bubble in module to be mixed into, the productivity of module can be improved significantly.

The explanation of symbol

1 operation sheet

11 double screw extruders

12 die heads

13a polishing roll (surface is without Carving Machining)

13b polishing roll (surface is without engraving)

13b ' dandy roll (there is Carving Machining on surface)

13c polishing roll (surface is without Carving Machining)

14 rolls

15 annealing furnaces

16 heaters

17 conveying rollers

18 are taken out roller

19 embossing opposed roll

20 dandy rolls

21 chill rolls

31 gear pumps

32 throughput directions

33 non-contact infrared thermometers.

Claims (11)

1. a manufacture method for solar cell sealing sheet material, carries out following operation (a), operation (b) and operation (c) successively,

Operation (a): by the resin combination of melting is shaped to sheet by heating, then cool, thus obtain the operation of operation sheet;

Operation (b): at least one surface heating of the operation sheet that will be obtained by described operation (a) 22 ~ 55 seconds, adds at this operation hankering making the temperature on this surface to reach the temperature of more than the fusing point of the resin combination forming this surface portion;

Operation (c): making in described operation (b) by the temperature on the surface of warmed-up operation sheet is (fusing point-10 DEG C of the resin combination of described formation surface portion) ~ (fusing point+20 DEG C of the resin combination of described formation surface portion), then to this surface pressing dandy roll, the operation of embossed shapes is formed on this surface.

2. the manufacture method of solar cell sealing sheet material according to claim 1, in described operation (c), when pressing described operation sheet surperficial with described dandy roll, the linear pressure that this surface is subject to is 150 ~ 500N/cm.

3. the manufacture method of solar cell sealing sheet material according to claim 1 and 2, in described operation (c), when pressing described operation sheet surperficial with described dandy roll, make the surface temperature of this dandy roll be (fusing point-20 DEG C of the resin combination of described formation surface portion) below.

4. the manufacture method of solar cell sealing sheet material according to claim 1 and 2, in described operation (a), single screw extrusion machine or double screw extruder is used to be extruded from die head by the resin combination of the melting by described heating and be shaped to sheet.

5. the manufacture method of solar cell sealing sheet material according to claim 1 and 2, the resin combination of described formation surface portion comprises polyolefin-based resins and organic peroxide.

6. a solar cell sealing sheet material is the solar cell sealing sheet material obtained by the manufacture method described in any one of Claims 1 to 5,

The resin combination of described formation surface portion comprises polyolefin-based resins,

Every square centimeter, the surface being formed with described embossed shapes has the individual bumps of 40 ~ 2300 height 60 ~ 300 μm, and the height T of this individual bumps is 0.05 ~ 0.80 with the ratio T/D of base length D.

7. solar cell sealing sheet material according to claim 6, when described solar cell sealing sheet material being placed in the warm water of 80 DEG C 1 minute, the heat shrink rate of the sheet flow direction of sealing sheet material is less than 30%, and described flow direction is the direction of the operation sheet flowing in the manufacturing process of seal stock.

8. the solar cell sealing sheet material according to claim 6 or 7, the shape of described individual bumps is hemispherical and/or corner taper.

9. the solar cell sealing sheet material according to claim 6 or 7, when the face with described projection of described solar cell sealing sheet material is compressed 100 μm along the thickness direction of sealing sheet material, the resilience stress of sheet is below 70kPa.

10. the solar cell sealing sheet material according to claim 6 or 7, bossed of the tool of described solar cell sealing sheet material has the projection of height 1 ~ 15 μm further.

11. 1 kinds of solar modules, consist of: containing sensitive surface guard member, back-protective part and to be configured between this sensitive surface guard member and back-protective part and to be sealed with the layer of solar battery cell by the solar cell sealing sheet material described in any one of claim 6 ~ 10.