JP4208672B2 - Laminated glass and its manufacturing method - Google Patents

Description

  The present invention relates to a method for producing a laminated glass in which a solar cell element (solar cell, photoelectric conversion element) is enclosed, and a laminated glass that can be produced by this production method.

  A solar cell module in which a solar cell element is fixed in a pair of plate-like bodies is known from Patent Document 1, for example. Patent Document 1 discloses a method for manufacturing a solar cell module in which a plurality of solar cell elements are sandwiched between a translucent member such as glass and a back member such as an aluminum foil. As disclosed in this document, a solar cell element is usually installed in a chamber together with a translucent member, a back surface member, and a resin film disposed between the member and the element. The resin film is softened by heating while reducing the pressure, and is sandwiched between the translucent member and the back member.

  Patent Document 2 proposes that a glass fiber nonwoven fabric or an organic resin fiber nonwoven fabric be inserted into a laminate to be a module so that no bubbles remain in the solar cell module.

  Patent Document 3 proposes to insert a base material having an opening into a laminated body that is a solar cell module, for the purpose of preventing the positional deviation of the solar cell element.

  Patent Document 4 proposes to insert a sealing material film having a concavo-convex structure on the surface of a laminated body as a module so that no bubbles remain in the solar cell module.

On the other hand, a laminated glass in which a pair of glass plates is joined with a resin film (intermediate film) such as polyvinyl butyral (PVB) or ethylene-vinyl acetate copolymer (EVA) for use as a window glass for vehicles and buildings. Has been mass-produced. The bonding process with heating for bonding is industrially performed using a heating furnace and an autoclave, or using only a heating furnace.
Japanese Patent Laid-Open No. 10-214987 Japanese Patent Laid-Open No. 11-112007 JP 2001-60709 A JP 2002-134768 A

  When a solar cell element is fixed between a pair of glass plates, photoelectric conversion is performed in a region where the element is disposed, and a light-transmitting module with a photoelectric conversion function that takes in light from other regions can be obtained. However, when the solar cell element is fixed between a pair of glass plates by applying a known bonding method using an air bag or a single chamber, force is concentrated on the solar cell element before the intermediate film is sufficiently softened. Therefore, the solar cell element is frequently cracked due to the generation of the local stress.

  Therefore, in the present invention, a resin member is arranged between the glass plates separately from the two conventionally used resin films.

That is, the present invention provides a laminated glass in which a plurality of solar cell elements, which are arranged so that their light receiving surfaces face in the same direction and at least a part of them are electrically connected in series, are sandwiched between first and second glass plates. A manufacturing method of
In order to arrange the first resin film, the plurality of solar cell elements, and the second resin film in this order on the first glass plate, and to electrically connect the plurality of solar cell elements A resin member made of the same material as that of the resin film is disposed under a conducting wire that spans between a light receiving surface of an adjacent solar cell element and a non-light receiving surface on the opposite side so as not to overlap the solar cell element. Supporting the conductive wire and setting the first resin film thicker than the second resin film,
Disposing the second glass plate on the second resin film,
While the lower surface of the first glass plate is supported by the flat support surface of the support member, the first and second resin films and the resin member are softened by heating, whereby the first and second resin films are softened . A method for producing a laminated glass that integrates the glass plate, the plurality of solar cell elements, the first and second resin films, and the resin member is provided.

  The number and shape of the resin members are not limited.

  According to the present invention, since the resin member relieves local stress applied to the solar cell element, the solar cell element can be fixed in the laminated glass while suppressing cracking.

  Hereinafter, embodiments of the present invention will be described.

  The production method of the present invention can be applied to the production of a solar cell module using one solar cell element, but is arranged such that a plurality of solar cell elements, specifically, the light receiving surfaces face the same direction, and at least The effect is great when applied to the manufacture of solar cell modules using a plurality of solar cell elements, some of which are electrically connected in series. Moreover, the manufacturing method of this invention is applicable regardless of the kind of apparatus used for bonding.

  The conducting wire that spans between the elements for electrical connection of the solar cell elements may be fixed in advance to the two elements to be connected, and the conducting wire that is fixed in advance only to one element is a glass plate. In the bonding step, contact with the other element may be ensured. What is necessary is just to carry out by soldering etc., when conducting wire is previously fixed to an element.

  In any case, the plurality of solar cell elements include a lead drawn from the light-receiving surface or the non-light-receiving surface, and a surface (conductor lead-out surface) from which the lead in the element adjacent to the element from which the lead is drawn is sequentially drawn. It is good to be in a state of being electrically connected in series by connecting to the opposite surface (conductive wire non-drawing surface).

  When the conducting wire drawing surface is a light receiving surface, the conducting wire non-drawing surface is a non-light receiving surface. In consideration of the connecting work of the conducting wire and the quality of the solar cell module, it is preferable that the conducting wire drawing surface is the light receiving surface.

  In the manufacturing process of laminated glass including solar cell elements electrically connected in series, the first resin film is usually disposed below these elements. A part of the conducting wire is interposed between them. In this case, if the thickness of the first resin film is 1.0 mm or more, the cracking of the solar cell element can be further suppressed. The first resin film is preferably thicker than the second resin film. According to these preferable forms, it is possible to reduce the cracking of the element in the vicinity of the conducting wire in contact with the first resin film.

  In the manufacturing method of the present invention, the plurality of elements are arranged in a matrix so that each of the plurality of solar cell elements forms a predetermined number of element columns and element rows, and the plurality of elements constituting the element column are electrically connected. It can also be applied to a form connected in series. In this form, the region between the element columns and the area between the element rows can be used as a light-transmitting area through which light passes. What is necessary is just to ensure the electrical connection of the solar cell element which comprises an element row | line | column with the conducting wire arrange | positioned similarly to the above.

  In this case, a resin member may be disposed in a region between element columns and a region between element rows. The resin member may be arranged in the region so as to cross at least one selected from a plurality of element columns and a plurality of element rows. This is because the placement work can be performed efficiently.

  Further, two or more members may be used as the resin member. For example, the resin member disposed below the conducting wire is used as the first resin member, and the second resin member is used together with the first resin member. It is preferable to further arrange the resin member so that the total thickness of the resin member is larger than the region where only the first resin member is arranged in at least a part of the region where the two resin members are arranged. This is because the stress applied to the end of the element can be relaxed.

  Although the shape of the resin member is not limited as described above, it is preferable to use a strip-shaped resin member particularly when a plurality of elements are arranged in a matrix. Further, a strip-shaped resin member that traverses a plurality of element rows and a strip-shaped resin member that traverses a plurality of element rows in an intersecting region where regions between the element rows and regions between the element rows overlap. You may arrange | position so that it may overlap. According to this arrangement, the resin member in the intersecting region becomes relatively thick, and it is possible to suppress the concentration of force on the element end portion until the resin film and the resin member are fluidized by heating.

  In the manufacturing method of this invention, it is preferable to arrange | position a resin member so that it may not overlap with a solar cell element. Moreover, if the resin member is arranged so that a gap is ensured between the solar cell element and the resin member, there is an effect in suppressing the remaining bubbles after alignment. In particular, when the resin members are arranged so that the gaps are conducted to the end of the laminated glass in a state where the respective members are laminated (before the resin film is softened), it is difficult for bubbles to remain.

  In the production method of the present invention, when at least one selected from the resin film and the resin member is EVA, the cooling time from the highest temperature to room temperature in the bonding step for integration is preferably 30 minutes or less. . In this case, it is preferable that the average temperature increase rate from room temperature to 70 ° C. is 1.5 ° C./min or more in the bonding step for integration.

  In the present invention, any one of the light receiving surface and the non-light receiving surface that are in a front / back relationship in the solar cell element may be used as the lead-out surface, and any of them may be arranged upward in the alignment step. However, if the light receiving surface is arranged upward, the second resin film in contact with the light receiving surface can be kept thin even if the first resin film in contact with the non-light receiving surface is thickened. Can be maintained. As a result, a laminated glass with high power generation efficiency can be manufactured while suppressing cracking of the element.

  In the present invention, the lead wire drawing surface may be arranged either upward or downward. When the light receiving surface is the lead-out surface, from the above viewpoint, the lead-out surface should be facing upward, but the other end of the lead wire with one end drawn from the element in the bonding process of the glass plate is the adjacent element. In the case where contact is made sequentially, it is better to take the lead-out surface of the conductor downward and the non-lead-out surface of the conductor upward from the viewpoint of workability.

  In addition, it is preferable that the difference in the thickness of the two resin films in contact with both surfaces of the element is, for example, 0.2 mm or more after the bonding step (that is, in the state of laminated glass).

  Hereinafter, details of the present invention will be described with reference to the drawings.

  First, the contents of the preliminary experiment will be described. When attempting to fix a plurality of solar cell elements between the glass plates in a state of being separated from each other, there are problems such as element breakage, element displacement and remaining bubbles. Therefore, in this preliminary experiment, a solution that was initially considered optimal for solving these problems, that is, a resin film 53 (with a window 10 and an air vent slit 18 formed by hollowing out portions where a plurality of elements are arranged) An attempt was made to interpose FIG. 1) as a third resin film between two resin films used for bonding element surfaces. This preliminary experiment is based on the disclosure of Patent Document 3.

  The order of lamination of each member was as follows. First, the first resin film is disposed on the lower glass plate. Next, the solar cell elements are arranged in a matrix on the first resin film, and the respective elements are connected in series in the element row direction. Each element has a conductive wire drawn from the peripheral end of the upper surface (light receiving surface in this element) sequentially interposed between the lower surface (non-light receiving surface) of the adjacent element and the first resin film, Connected in series with each other. And the edge part of conducting wire was connected to the external lead-out line. Further, the resin film 53 shown in FIG. 1 is arranged as a third resin film from above the conducting wire so that each element is arranged in the window 10. Finally, a second resin film and an upper glass plate are laminated in this order on this resin film. Here, the lead-out surface is the top surface, but in consideration of workability, the lead-out surface (light-receiving surface) may be disposed on the bottom surface.

  When this laminated body and a conventional laminated body in which the third resin film was not disposed were subjected to a combined test, the arrangement of the third resin film substantially solved the positional deviation of the elements and the remaining bubbles. However, the probability of device cracking could hardly be improved even when the third resin film 53 was disposed.

  When the results of the preliminary experiment were analyzed, element cracks could be classified into the following three patterns (FIG. 2). The first is a crack 41 around the connection portion (tab fixing portion) of the conducting wire (tab wire) 17 drawn from the upper surface of the element 16. The second is a crack 42 that occurs along the conductor 7 in contact with the lower surface of the element 16. The third is a crack 43 that occurs in the vicinity of a corner portion (even angle portion) of the rectangular element 16 in plan view.

  The first crack 41 is generated when the second resin film (upper resin film) 14 and the upper glass plate 15 press the conductor 17 from above between the elements 16 and 26 when viewed from the generation site. (Figure 3). Due to the pressure from above, the conductor 17 is pushed down so as to wind up the element 16, and as a result, the end of the element 16 becomes a lever fulcrum, and stress is applied to the narrow connection portion with the conductor 17 at the peripheral edge of the element upper surface 16a. concentrate.

  As shown in FIG. 3, the end portion of the conducting wire 17 drawn from the upper surface 16 a of the element is formed between the first resin film 12 held on the lower glass plate 11 and the adjacent element 26. Arranged between. The conducting wire 17 is fixed between the first resin film 12 and the lower surface 26b of the element 26 by bonding a glass plate, and connects the elements 16 and 26 via the conductive non-light-receiving surface 26b. The element 26 is further connected to an adjacent element (not shown) via a conducting wire 27 drawn from the upper surface 26a. Similarly, the element 16 is adjacent to the opposite side via a conducting wire 7 in contact with the lower surface 16b. It is connected to an element (not shown). In this way, a plurality of elements... 16, 26.

  The second crack 42 is considered to be directly caused by bending stress generated when the conductor 17 is interposed under the element 26 in view of the fact that the crack is generated along the conductor 27 ( FIG. 4). On the lower glass plate 11 placed on the flat support surface of the support member 30, the element 26 is pressed from the upper side on both sides of the conductive wire 17, so that stress concentrates in the region 55 along both sides of the conductive wire 17. To do.

  The third crack 43 is caused by the stress generated when the glass plate 15 bends slightly in the region where the band-like region between the element columns and the band-like region between the element rows intersect (intersection region 20; FIG. 1). I think that.

  Among the first to third cracks, the first crack 41 was the most frequent. Therefore, when the third resin film 13 is disposed under the conducting wire 17 in order to suppress the first crack (FIG. 5), the occurrence probability of the element crack is drastically reduced. This is presumably because the third resin film 13 supported the conducting wire 17 from the lower side and relaxed the stress concentration at the conducting wire connecting portion of the upper surface 16a. As described above, the first crack is caused by the resin films 12 and 14 used for bonding the element surface between the conductive wire 17 drawn from the upper surface 16a of the element and the resin film 12 in contact with the lower surface 16b of the element. It can suppress by arrange | positioning another resin film 13. FIG.

  The thickness of the resin member is preferably the same as or slightly thicker than the solar cell element. Here, the resin film is used as the resin member disposed under the conducting wire, but there is no particular limitation on the shape or the like as long as stress concentration on the conducting wire connecting portion can be reduced. For example, a resin rod-like body or resin piece The laminate may be used as a resin member.

  Since the first crack is dramatically reduced by the addition of the third resin film 13, it is possible to obtain a sufficiently practical production yield without taking special measures against the second and third cracks. It is. Even if the first crack 41 is suppressed, the second and third cracks 42 and 43 do not increase significantly. However, in order to obtain a higher manufacturing yield, the following countermeasures may be taken for these cracks 42 and 43.

  In order to suppress the second crack 42, the lower resin film (first resin film) 12 may be thickened to increase the “cushion effect” by the resin film. This effect is effective in relieving the bending stress that causes the second crack. In the normal alignment process, it is sufficient that the resin films 12 and 14 have a thickness of about 0.8 mm. However, in order to prevent this kind of crack 42, the thickness of the resin film is preferably 1.0 mm or more. In the range confirmed by the experiment using EVA, when the film thickness is 1.2 mm or more, the second crack 42 is not seen at all. Even in the cooling step after heating, stress is applied to the vicinity of the conductive wire 17, but when the lower resin film 12 is made thicker, the stress accompanying the temperature drop of the resin film can be relaxed.

  It seems that the temperature rise rate of the resin film also affects the generation of the second crack 42. This is because if the fluidity of the resin film can be ensured by the time when the bending stress exceeds the strength of the element, the bending stress is relaxed. This bending stress is relieved if the resin film 12 is plastically deformed to such an extent that a part of the conducting wire 17 disposed under the element is buried in the resin film 12. This level of fluidity can be obtained, for example, by heating to 70 ° C. for EVA. Therefore, when EVA is used as the resin film, the resin film is heated so that the average temperature rise rate of the resin film from room temperature to 70 ° C. is a predetermined value or more, for example, 1.5 ° C./min or more. Is preferred. In particular, since the second crack is considered to have occurred in the temperature range of 50 to 70 ° C. until EVA begins to soften and fluidity is obtained, the average heating rate in this temperature range is at least 1.5. More preferably, the temperature is set to ° C / min, and more preferably 3.0 to 5.0 ° C / min.

  The third crack 43 can be suppressed by increasing the thickness of the third resin film 13 in the intersection region 20 or in the vicinity of the region, or by increasing the temperature increase rate to a predetermined value or more. This is because the stress applied to the corner portion of the element 16 is relaxed during heating and cooling. Specifically, the resin film 13 in this region 20 is preferably thicker than the resin film in other regions. Further, by setting the average temperature rising rate of the resin film from room temperature to 70 ° C. to 1.5 ° C./min or more, the end of the solar cell element is obtained until the resin film or the resin member acquires fluidity. Can be prevented from being concentrated on

  The partial thickening of the resin film in the intersecting region 20 can be easily realized by using a strip-shaped resin film (FIG. 6). The strip-shaped resin film is simply a region between element columns (inter-element column region) composed of elements 16 connected in series with each other by a conductive wire 17 and a row of virtual elements 16 extending in a direction perpendicular to the element columns. What is necessary is just to arrange | position so that each element column and each element row may be traversed along the area | region (element area | region between element rows) between (element row). The strip-shaped resin film 23 arranged along the inter-element region and the strip-shaped resin film 33 arranged along the inter-element region overlap each other in the intersecting region, and become thick locally at the overlapping portion 21.

  Also in the preferred embodiment shown in FIG. 6, the resin film 33 disposed along the element row region is disposed under the conductor 17 connecting the elements 16.

  The element 16 and the third resin films 13, 23, and 33 may be arranged so as not to contact each other, and it is preferable to secure a gap in the entire periphery of the element as shown in FIG. 6. A preferable interval between the element and the third resin film is about 0.5 mm to 5 mm. The gap of this degree functions as an air vent passage that vents the internal air when the resin film is softened, but is eliminated when the temperature of the resin film falls to near room temperature, and the element and the resin film are in close contact with each other. It does not cause the rest.

  In the form shown in FIG. 6, the air vent passages 29 and 39 extend vertically and horizontally along the strip-shaped resin films 23 and 33 (that is, the passages are in contact with the entire periphery of the element), and these passages 29 , 39 are conducted to the end of the laminated glass, so that the internal air can be discharged reliably.

  The larger the glass plate, the more important the air vent passage. About each element, it is good to arrange | position a 3rd resin film so that the air vent passage which conduct | electrically_connects to the edge part of a laminated glass is ensured.

  The strip-shaped resin film may be divided in preference to a more reliable release of the internal air (FIG. 7). FIG. 7 illustrates an example in which the resin film 23 extending along the element array region is divided so that the resin films do not overlap to form a plurality of resin films 23 ′. In this case, in order to suppress the third crack 43, the resin film 23 'is preferably thicker than the resin film 33 that passes under the conductive wire. Further, the resin film 33 may be divided like a resin film 23 '.

  Thus, in order to suppress the 3rd crack 43, in addition to the resin film (1st resin member) for supporting a conducting wire, an additional resin film (2nd resin member) is arranged, and this addition In at least a part of the region where the resin film is disposed, specifically, in a region other than the portion where the first resin member supports the conductive wire, than the region where only the resin film for supporting the conductive wire is disposed. The total thickness (total thickness) of the resin film may be increased. In the form shown in FIG. 6, since the resin films 23 and 33 intersect, the sum of the thicknesses of both resin films is the total thickness of the resin films.

  This total thickness is preferably equal to or greater than the total thickness of the element including the thickness of the conducting wire. For example, when the thickness of the element body is 0.4 mm and the thickness of the conducting wire is 160 μm, the total thickness of the element is about 0 considering that the conducting wire 17 overlaps the light receiving surface 16a and the non-light receiving surface 16b of the device. 72 mm. Therefore, in this case, the total thickness of the resin film is preferably 0.72 mm or more. In order to realize this thickness, the thickness of the strip-shaped resin film is preferably 0.4 to 0.8 mm. In the present specification, the thickness of the resin film is evaluated by the thickness before the alignment step.

The glass plate is not particularly limited, and general-purpose soda lime silica glass may be used. In particular, the glass plate 15 arranged on the light receiving surface side has reduced iron content in order to secure the amount of light transmitted to the element. Glass should be used. Specifically, the total iron amount converted to Fe ₂ O ₃ is preferably 0.2 wt% or less as the coloring component.

  As the resin film, PVB or EVA conventionally used for the production of laminated glass is suitable, but not limited thereto, polyurethane or the like may be used. Note that EVA is suitable for encapsulating solar cell elements because of its high fluidity during softening. In addition, when using EVA, it is not necessary to use an autoclave for bonding of two glass plates. The material of the third resin film (resin member) is not particularly limited, but it is sufficient to use a resin having the same material as that of the resin film used together.

  There is no restriction | limiting also in the external shape of a solar cell element, an internal structure, etc. In this specification, although the form which connects the conducting wire (tab line) pulled out from the upper surface to the lower surface of an element was shown, the form of tab line connection is not restricted to this, You may prepare a connection member separately. Moreover, you may use the element group which connected the several solar cell element previously instead of connecting an element mutually in a matching process. In this case as well, an element group is used in which the conductors drawn from the elements are sequentially electrically connected to the opposite surface of the adjacent elements (non-light-receiving surface if the lead-out surface is a light-receiving surface) with solder or the like. Good.

  For the production of the laminated glass of the present invention, a conventionally used device sealing device (depressurized chamber of single chamber type, airbag type or the like) may be applied. Moreover, you may further apply the autoclave which has been used for manufacture of a laminated glass. When heated to a predetermined temperature in a reduced-pressure atmosphere to soften the resin film and fix the element (temporary bonding), and subsequently heated to a temperature higher than the predetermined temperature in a pressurized atmosphere (main bonding), the first In addition, the space between the second glass plate and the element can be filled with resin to eliminate unfilled portions.

  In order to make the effect of the present invention more reliable, the lower surface of the lower glass plate is preferably supported by a support member 30 as shown in FIG. It is preferable to hold | maintain on a support member in each step. At the stage where the main bonding is completed, the solar cell module may be stored vertically or may be reversed so that its front and back sides are interchanged.

  In the main bonding, a sufficient bonding strength of the laminated glass cannot be obtained unless it is maintained at the maximum temperature range for 20 to 30 minutes. For this reason, it is not appropriate to shorten the holding time in the maximum temperature range, and in order to improve the workability of the bonding process, it is necessary to increase the heating rate and the cooling rate as much as possible. However, if it is too fast, the in-plane temperature difference of the laminated glass increases, adhesion failure occurs, and the laminated glass may be deformed. Therefore, it is preferable to control the heating rate and the cooling rate to 1.5 to 7.0 ° C./min, particularly 3.0 to 5.0 ° C./min. An autoclave is suitable for precise control of the heating rate and cooling rate.

  When EVA is used as a resin film or a resin member, the cooling time in the main bonding greatly affects the characteristics regardless of the presence or absence of temporary bonding. According to experiments, it has been found that EVA becomes cloudy when the time (cooling time) required for cooling from the highest temperature (for example, 150 ° C.) to the room temperature in the main bonding exceeds 30 minutes. This is considered because EVA crystallizes. When at least one selected from the resin film and the resin member is EVA, the cooling time from the highest temperature to the room temperature in the bonding step is preferably 30 minutes or less.

  Hereinafter, the present invention will be described in more detail with reference to examples.

  Soda lime silica glass (dimensions 1400 mm × 2800 mm, thickness 5.0 mm) and EVA interlayer (manufactured by Bridgestone (WG1820, WG1620, WG1420): thickness 0.4 mm, 0.6 mm or 0.8 mm, main bonding temperature 150 ° C.) and a solar battery cell (manufactured by Kyocera Corporation). Here, the main adhesion temperature is a temperature that should be set as the maximum temperature to be performed in the autoclave using the resin film.

  In addition, as soda-lime silica glass, the high transmittance glass of 0.2 wt% or less of the total iron amount arrange | positioned at the light-receiving surface side, and the normal glass arrange | positioned at the non-light-receiving surface side were prepared.

  The solar cell has a rectangular size of 150 mm × 155 mm and a thickness of 0.35 to 0.40 mm, and a pair of conductive wires (tab wires) are led out from the peripheral edge of the light receiving surface. The width and thickness of the tab line are 2 mm and 0.2 mm, respectively. The non-light-receiving surface of the cell is a back electrode made of aluminum, and the electromotive force of the cell can be taken out between the tab wire and the back electrode.

  Furthermore, a strip-shaped EVA film was prepared as the third resin film. This EVA film is obtained by cutting an EVA film having a thickness of 0.4 mm prepared as an EVA intermediate film (first and second resin films) into a strip shape having a width of 10 mm.

  These members were laminated in the order of a lower glass plate, a first EVA intermediate film, a solar battery cell and a strip-like EVA film, a second EVA intermediate film, and an upper glass plate. However, as the first EVA intermediate film, two or three EVA intermediate films were appropriately stacked to obtain a predetermined film thickness. The second EVA intermediate film was made to have a thickness of 0.8 mm by stacking two EVA films having a thickness of 0.4 mm.

  At this time, the solar cells were arranged so that the light receiving surface was the lower surface. In addition, the 4 × 10 matrix is arranged, and for the four columns, the end portions of the tab lines are sequentially interposed between the adjacent cells and the EVA intermediate film, and the cells in this column are connected in series. . An interval of about 15 mm was secured between the four columns and 10 rows of the cell.

  As shown in FIG. 6, the strip-like EVA film and the solar battery cell were arranged so that the EVA film crossing the element row passed under the tab line. An average interval of about 2.5 mm was secured between the strip-shaped EVA film and the cell.

  The laminated body thus obtained was primarily bonded by the single chamber method under the following conditions.

[Primary bonding conditions]
-Average temperature in the chamber: 110 ° C (resin film temperature: 85-95 ° C)
-Chamber pressure: about 98 kPa
-Holding time of the above average temperature: 40 minutes-Rate of temperature increase: about 1.5 ° C / minute After primary adhesion, secondary adhesion was performed using an autoclave under the following conditions.

[Secondary bonding conditions]
・ Set temperature: 150 ℃
・ Set pressure: 490kPa
-Average heating rate to set temperature: 4.0 ° C / min-Holding time for the above set temperature: 30 minutes-Average cooling rate from set temperature to room temperature: 4.0 ° C / min-Cooling time: 30 minutes- Time for a series of heat treatment steps from room temperature to set temperature to room temperature: 90 minutes

  For comparison, a laminated glass was produced in the same manner as described above except that the third resin film (EVA film) was not used (Comparative Example 1). Further, a laminated glass was produced in the same manner as described above except that the third resin film (EVA film) was disposed on the tab line (Comparative Example 2). Further, a laminated glass (Comparative Example 3) produced in the same manner as in Comparative Example 2 is also subject to evaluation, except that an EVA film (see FIG. 1) in which a cell is disposed is used instead of the strip-shaped EVA film. It was. Comparative Example 3 corresponds to the result of the preliminary experiment described above. The EVA film used in Comparative Example 3 was formed by stacking two EVA films having a thickness of 0.4 mm.

  About the some laminated glass obtained in this way, "bubble remaining", "cell shift | offset | difference", and "cell crack" were confirmed visually. In addition, as the “cell deviation”, the movement distance of the cell that is the most shifted from the position before the primary adhesion was evaluated, and the movement distance of 0.5 mm or less was within the allowable range. The results are summarized in Table 1.

(Table 1)
―――――――――――――――――――――――――――――――――――
Lower interlayer film Resin member Laminated glass Thickness Shape Thickness Positional relationship Air bubble remaining Cell shift Cell cracking
―――――――――――――――――――――――――――――――――――
Example 1 0.8 Strip 0.4 Lower 0 Tolerance 0.25
2 1.0 Strip 0.4 Lower 0 Tolerable range 0.11
3 1.2 Strip 0.4 Lower 0 Tolerable range 0.06
―――――――――――――――――――――――――――――――――――
Comparative Example 1 0.8 None − − 10 5mm or more 20
2 0.8 Strip 0.4 Top 0 Tolerance 20
3 0.8 Drilled 0.8 Top 0 Allowable range 20
―――――――――――――――――――――――――――――――――――
With respect to the resin member, “lower (upper)” indicates that the resin member is arranged at “lower (upper)” of the tab line.

  In order to investigate the relationship between the cooling time in the main bonding and the crystallization of EVA, a laminated glass was produced in the same manner as in Example 1 except that only the cooling rate was changed. Specifically, three sheets were produced at an average cooling rate of 7.0 ° C./min (Example 4), and three sheets were produced at an average cooling rate of 3.0 ° C./min (Reference Example). About these laminated glasses, when the part which does not have a solar cell element was cut out and the haze rate of the part was measured, both the laminated glasses of Example 1 and Example 4 were 1.0% on average. The haze ratio of the laminated glass of the reference example was 15.0% on average. Considering the cooling time (40 minutes) in the reference example, it can be seen that the cooling time is preferably 30 minutes or less.

  The laminated glass in which the solar cell element is encapsulated can be expected to be used in various fields such as windows and roofing materials of buildings and vehicles as a translucent member with a photoelectric conversion function having excellent durability.

It is a top view of the resin film used in the preliminary experiment. It is the top view which looked at the solar cell element from the light-receiving surface, and the typical pattern of the cell crack is filled in in order to explain an element (cell) crack. It is sectional drawing for showing arrangement | positioning of the resin film in a preliminary experiment. It is II sectional drawing of FIG. It is sectional drawing for demonstrating the example of arrangement | positioning of the resin member (3rd resin film) in the manufacturing method of this invention. It is a top view for showing the example of arrangement | positioning of the strip-shaped resin film used as a 3rd resin film, and a solar cell element. It is a top view for showing another example of arrangement of the 3rd resin film and a solar cell element.

Explanation of symbols

11, 15 Glass plate 12, 14 First, second resin film 13, 23, 23 ', 33 Third resin film (resin member)
16, 26 Solar cell element (cell)
16a, 26a Light-receiving surface 16b, 26b Non-light-receiving surface 7, 17, 27 Conductor 18 Air vent slit of third resin film 20 Crossing region 21 Overlapping portion of third resin film 29, 39 Air vent passage 30 Support member 41, 42,43 cell crack

Claims (10)

A method for producing a laminated glass in which a plurality of solar cell elements, which are arranged so that their light-receiving surfaces face in the same direction and at least a part of them are electrically connected in series, are sandwiched between first and second glass plates, ,
In order to arrange the first resin film, the plurality of solar cell elements, and the second resin film in this order on the first glass plate, and to electrically connect the plurality of solar cell elements A resin member made of the same material as that of the resin film is disposed under a conducting wire that spans between a light receiving surface of an adjacent solar cell element and a non-light receiving surface on the opposite side so as not to overlap the solar cell element. Supporting the conductive wire and setting the first resin film thicker than the second resin film,
Disposing the second glass plate on the second resin film,
While the lower surface of the first glass plate is supported by the flat support surface of the support member, the first and second resin films and the resin member are softened by heating, whereby the first and second resin films are softened. A method for producing a laminated glass in which the glass plate, the plurality of solar cell elements, the first and second resin films, and the resin member are integrated.   The manufacturing method of the laminated glass of Claim 1 which sets the film thickness of a 1st resin film to 1.0 mm or more.   The plurality of solar cell elements are arranged in a matrix so that each of the plurality of solar cell elements constitutes a predetermined number of element rows and element rows, and the plurality of solar cell elements constituting the element row are electrically connected by conducting wires. The manufacturing method of the laminated glass of Claim 1 which arrange | positions the said resin member under the said conducting wire in the area | region between the said element rows while connecting in series.   A strip-shaped first resin member is arranged as a resin member to be arranged under the conducting wire so as to cross a plurality of element rows in a region between the element rows, and a second resin member is arranged in a region between the element rows. The manufacturing method of the laminated glass of Claim 3 which arrange | positions.   A strip-shaped second resin member is arranged so as to cross the plurality of element rows and to overlap the first resin member in the intersecting region where the region between the element columns and the region between the element rows overlap. The manufacturing method of the laminated glass of Claim 4 to do.   The alignment according to claim 4, wherein a second resin member is disposed so as not to overlap the first resin member in a region between the element rows, and the second resin member is made thicker than the first resin member. Glass manufacturing method.   The manufacturing method of the laminated glass of Claim 1 which arrange | positions the said resin member so that a clearance gap is ensured between a solar cell element and a resin member.   The manufacturing method of the laminated glass of Claim 7 which arrange | positions a resin member so that a clearance gap may conduct | electrically_connect to the edge part of a laminated glass.   The resin film and the resin member are ethylene-vinyl acetate copolymers, and the cooling time from the highest temperature to room temperature in the bonding step for integration is 30 minutes or less. Of manufacturing laminated glass.   The resin film and the resin member are ethylene-vinyl acetate copolymers, and an average temperature increase rate from room temperature to 70 ° C. is 1.5 ° C./min or more in the bonding step for integration. The manufacturing method of the laminated glass in any one of -8.