JP2008115057A - Sealant, manufacturing process of glass panel and dye-sensitized solar cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid the occurrence of damages such as cracks and breakage to glass substrates even made of soda lime glass, etc., in the manufacture of glass panels in which pasty sealant comprising glass powder is coated on the glass substrates to form sealing layers, two pieces of the glass substrates are bonded by irradiating the sealing layers with laser beam. <P>SOLUTION: The sealant contains a laser absorbing component comprising not less than one kind of simple element or compound of any of chromium, iron, cobalt, manganese, copper and carbon and a glass component. The difference in coefficient of thermal expansion between the sealant and a material member to be sealed is ≤10×10<SP>-7</SP>/°C. Sealing layer 3 composed of the sealant is formed on sealing positions at least on one of the glass substrates 1. Another glass substrate 2 is laid on top of the substrate. The two glass substrates are bonded by melting the sealing layer by irradiating the sealing layer 3 with laser beam. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sealing material used for sealing a glass substrate and the like, a photoelectric conversion element such as a dye-sensitized solar cell using the sealing material, a liquid crystal display element, an electroluminescence element, an electrochromic element, plasma The present invention relates to a method for producing a glass panel constituting a display element, a double glass panel, and the like, and a dye-sensitized solar cell.

  This type of glass panel is formed by joining two glass substrates at the periphery with a sealing material made of a resin such as an epoxy resin, an ultraviolet curable resin, or an ionomer, and from the outside to the space in the panel. Intrusion of foreign matter, moisture, gas, etc. is prevented, and when fluid such as electrolyte or liquid crystal is sealed in the space, leakage of this fluid to the outside is prevented.

  However, since such a glass panel uses a sealing material made of resin, there is concern about the long-term reliability of sealing performance, and in order to improve this, glass powder made of metal oxide It has been proposed to use as a sealing material. For example, JP 2003-192378 A discloses a sealing material made of glass powder containing boron oxide, vanadium oxide, barium oxide, and zinc oxide. Japanese Patent Application Laid-Open No. 2004-59366 discloses a sealing material made of glass powder containing tin oxide, phosphorus oxide, zinc oxide, silicon oxide, and chlorine.

  In the sealing materials of these prior inventions, this is made into a paste and applied to the peripheral edge of one glass substrate and dried to form a sealing layer. The sealing layer is irradiated with laser light to heat and melt the sealing layer, and the two glass substrates are joined.

Although such a glass sealing material has the advantage of improving the long-term reliability of the sealing performance, when a glass substrate made of soda lime glass having a high coefficient of thermal expansion is used as the glass substrate, laser light is used. After the irradiation, there was a problem that the glass substrate was cracked or damaged.
JP 2003-192378 A JP 2004-59366 A

  Therefore, the problem in the present invention is that a sealing material made of glass powder is applied as a paste to a glass substrate to form a sealing layer, and this sealing layer is irradiated with laser light to join two glass substrates. Then, when manufacturing a glass panel, it is in preventing breakage, such as a crack and a crack, also in the glass substrate which consists of soda-lime glass.

To solve this problem,
The invention according to claim 1 includes a laser-absorbing component made of one or more of chromium, iron, nickel, cobalt, manganese, copper, and carbon, or a glass component and a sealed member made of glass. Is a sealing material having a difference in thermal expansion coefficient of 10 × 10 ⁻⁷ / ° C. or less.

  According to a second aspect of the present invention, after the sealing layer made of the sealing material according to the first aspect is formed on the sealing portion of at least one glass substrate, the other glass substrate is overlaid, and a laser is applied to the sealing layer. A method for producing a glass panel, comprising irradiating light to melt a sealing layer and joining two glass substrates.

  According to a third aspect of the present invention, on the other glass substrate, a transparent conductive film and a dye-supported metal oxide semiconductor layer on the transparent conductive film are formed on one of the glass substrates. A dye-sensitized solar cell produced by the production method according to claim 2, wherein a conductive film is formed on the inner surface.

  According to the present invention, the laser absorption component in the sealing material specifically absorbs the laser light and converts it into heat. For this reason, the irradiated laser light is selectively absorbed by the sealing layer, the sealing layer is efficiently heated and melted, and the members to be sealed can be joined in a short time.

In addition, since the difference in thermal expansion coefficient with the sealing member made of glass is 10 × 10 ⁻⁷ / ° C. or less, the shrinkage amount of the sealing layer and the sealing member during cooling is approximately the same, Cracks and cracks do not occur in a sealed member such as a glass substrate made of soda lime glass.

  Furthermore, a manufacturing process is simplified and production efficiency can be improved by applying the manufacturing method of a glass panel to manufacture of a dye-sensitized solar cell.

[Sealing material]
The sealing material of this invention contains a laser absorption component and a glass component, and the difference of a thermal expansion coefficient with the to-be-sealed member consisting of glass is 10 * 10 < ^-7 > / degrees C or less.
The laser absorbing component is composed of one or two or more of chromium, iron, nickel, cobalt, manganese, copper, and carbon.
As described above, the laser absorbing component has a function of specifically absorbing laser light and converting it into heat.

Specific examples of the laser absorbing component include carbon fiber, carbon black, coke, silicon carbide and the like. In addition, one or more kinds of single metals selected from Fe, Cr, Mn, Ni, Cu, Co, and Mo, or oxides such as iron oxide and nickel oxide, sulfates such as copper sulfate and nickel sulfate, manganese carbonate, and the like Examples thereof include metal salts such as carbonates and chlorides such as cobalt chloride.
Further, the laser absorption component may be melted in a part of the matrix constituting the glass component or segregated in a state where it does not dissolve in the matrix, and is not particularly concerned with the state.
The ratio of the laser absorbing component in the sealing material is 0.01 to 30% in mass ratio. If it is less than 0.01%, the laser light absorption effect is insufficient, and if it exceeds 30%, the sealing performance is exceeded. Decreases.

Examples of the glass component include SiO ₂ —Bi ₂ O ₃ —MO _X , B ₂ O ₃ —Bi ₂ O ₃ —MO _X , SiO ₂ —CaO—Na (K) ₂ O—MO _X , P ₂ O ₅ —MgO—MO _X system (M is one or more metal elements, X is an integer) is used, and basically, SiO ₂ skeleton, B ₂ O ₃ skeleton, P ₂ O ₅ skeleton. In addition, other metal oxides are contained for controlling the melting point and chemical stability.
Alkali metal and alkaline earth metal oxides added to B ₂ O ₃ , P ₂ O ₅ , Bi ₂ O ₃ , and SiO ₂ , which are the main components of each glass system, lower the melting point of the sealing material. .

For example, alumina, titania, zircon, silica, cordierite, mullite, β-eucryptite, spodomen, anorthite, celsian, forsterite can be used to control the thermal expansion coefficient of the glass component in the sealing material. Aluminum titanate or the like is used. And the compounding ratio of these oxide fillers is determined so that the difference between the thermal expansion coefficient of the sealing material and that of the member to be sealed is 10 × 10 ⁻⁷ / ° C. or less.

  Furthermore, the melting temperature of the sealing material is 600 ° C. or lower, preferably 400 to 550 ° C. In order to make the melting temperature within this range, it is possible to appropriately determine the blending amount of alkali metal oxide, alkali metal oxide, and other metal oxides contained in the glass component constituting the sealing material. It becomes.

  The sealing material is manufactured by first mixing a metal simple substance or metal compound powder constituting the laser absorption component and a metal oxide powder constituting the glass component in a predetermined amount ratio, putting the mixture in a crucible, and about 1000 to 1200 ° C. The mixture is heated and melted, and the cooled solidified product is pulverized by a pulverizer and classified to an average particle size of 100 μm or less, preferably 10 μm or less.

The sealing material of the present invention is used as a paste when used. The paste is prepared by adding an organic solvent, a resin, or the like to the powdery sealing material having the average particle diameter and kneading. The organic solvent or resin is preferably one that completely burns at a temperature of 500 to 600 ° C. and does not leave a residue. For example, polyvinyl alcohol, polyethylene glycol, ethyl cellulose, acrylic resin, or the like is used.
The ratio of the sealing material occupying in the paste is better from the thixotropy, and is at least 50% by mass or more.
The viscosity of the paste is a value measured by a rotational viscometer, and the measurement conditions are preferably 20 to 100 Pa · s at 20 ° C. and a rotation speed of 20 rpm.

  Further, examples of the glass constituting the member to be sealed that is bonded or sealed with this sealing material include soda lime glass, quartz glass, borate glass, lead glass, and the like, and are particularly limited to the type and composition of the glass. It is not something. Moreover, the board | substrate which consists of these various glass is used for manufacture of a glass panel.

[Glass panel manufacturing method]
Next, the manufacturing method of the glass panel of this invention is demonstrated.
First, a paste made of the above-described sealing material is applied to the periphery of one or both surfaces of two glass substrates, and dried and temporarily fired to form a sealing layer. The paste is preferably applied by screen printing, but may be applied by other blades, spray application, or the like.

The coating thickness of the paste may be about 50 to 300 μm, and the coating width may be about 1 to 5 mm, but if it is less than 1 mm, the sealing performance may be lowered.
After application of the paste, the glass substrate is heated at a temperature of 600 ° C. or lower, the paste is dried, and temporarily fired to form a sealing layer. When heated at a temperature exceeding 600 ° C., the sealing material melts and flows.

Next, the two glass substrates are overlaid so that the respective sealing layers are inside, and lightly pressed. Load during the ^{pressurization, 1gf / cm 2 ~10000gf / cm} 2, and preferably in the range of ^{10gf / cm 2 ~100gf / cm 2} .
In this pressurized state, the sealing layer is irradiated with laser light to melt the sealing layer and join the two glass substrates.

FIG. 1 schematically shows a bonding method by laser light irradiation. In the figure, reference numeral 1 denotes a first glass substrate, and reference numeral 2 denotes a second glass substrate.
A sealing layer 3 is formed on the sealing portions of the two glass substrates 1 and 2 by applying the paste, drying, and pre-baking.
Then, laser light from a laser light source (not shown) is guided to the laser head 4 and is irradiated from the laser head 4 through the second glass substrate 2 toward the sealing layer 3, thereby the two glass substrates 1. 2 are joined.

  FIG. 2 shows another bonding method. In this example, the entire two substrates 1 and 2 are arranged on the hot flate 5 so that the substrates 1 and 2 can be heated to 100 to 150 ° C. ing. Further, a weight member 6 for pressing the glass substrates 1 and 2 is placed on the second glass substrate 2. The laser beam from the laser head 4 penetrates from above the second glass substrate 2 and is irradiated toward the sealing layer 3.

  FIG. 3 shows another bonding method, in which a paste is further applied to the outside of the sealing layer 3 in FIG. 1, dried and pre-fired, and then the end face of the second glass substrate 2 and the outside of the sealing layer 3. Is coated with the outer sealing layer 31, and laser light is irradiated from the laser head 4 toward the outer sealing layer 31, and the outer sealing layer 31 and the sealing layer 3 are melted to form two glass substrates. 1 and 2 are joined.

Laser light from a carbon dioxide laser, excimer laser, YAG laser, HeNe laser or the like is used as the laser light, and a laser with a short wavelength is preferable from the viewpoints of laser light transmission to a glass plate, focus diameter, and the like. It is desirable to use a YAG laser that is widely used.
As a method of laser beam irradiation, only the sealing layer 3 can be locally heated and bonded by one laser beam, but bonding can also be performed by using two or more laser beams.

  Specifically, several hundred to several thousand μm in width are continuously irradiated around the sealing layer 3 so as not to create a local thermal gradient using the first laser light, and sealed with the second laser light. It joins by heating to the temperature which softens and melts the stop layer 3. At this time, without using the second laser beam, as shown in FIG. 2, the entire glass substrates 1 and 2 are placed on a heating device such as a hot plate 5 and heated to about 150 ° C. The same effect can be obtained by joining by heating to a temperature at which the sealing layer 3 is locally softened and melted by the laser beam 1.

As the laser oscillation mode, it is desirable that the pulse mode suppresses the glass substrate from cracking more than the continuous oscillation mode, and the oscillation frequency is 10 to 10,000 Hz. The laser power is preferably at least 10 W or more.
The scanning speed of the laser beam is not particularly limited, but is preferably 0.01 cm / sec or more from the viewpoint of production.
Also. When the product f × Φ of the laser oscillation frequency f and the laser beam diameter Φ is at least the laser scanning speed V, it is desirable that f × Φ ≧ V, and f × Φ is several times the scanning speed. The assist gas may be flowed so that the laser head 4 is not scratched or soiled when irradiated with laser light, and the type of gas such as air, oxygen, carbon dioxide, nitrogen, etc. is not particularly limited.

The irradiation time of the laser light is sufficient from 0.1 to 60 seconds per 1 cm, and since the sealing layer 3 contains a laser absorbing component, the sealing layer 3 is rapidly melted by a short laser irradiation.
If the sealing layer 3 cools and solidifies, the two glass substrates 1 and 2 will be joined by the sealing layer 3, and a glass panel will be obtained.
The peripheral edge of the glass panel produced in this way is fixed with an adhesive such as acrylic resin, epoxy resin, or urethane resin, and the outer peripheral part is protected with an elastic material such as butyl rubber or silicon rubber. It is desirable to reinforce the peripheral edge with a frame or SUS frame.

[Manufacture of dye-sensitized solar cells]
In the production of such a glass panel, as one glass substrate, a transparent conductive film made of ITO, FTO or the like on its inner surface and a dye-supported metal oxide semiconductor layer such as a titanium oxide film supporting a dye on the transparent conductive film Is used as the other glass substrate, and a glass panel is formed using a conductive film formed on the inner surface of the glass substrate, and then an electrolyte is injected into the voids inside the glass panel. A battery can be manufactured.

As a glass substrate used for a dye-sensitized solar cell, at least one of the two glass substrates is made of a soda lime glass material, and mainly contains oxides of Si, Ca, Na, K, Mg, and Al. In particular, the soda glass contains about 70 to 73% by mass of SiO _2, about 10 to 15% by mass of oxides of Na and K, and about 7 to 12% by mass of CaO. The softening temperature is 720 to 730 ° C., and the linear expansion coefficient is around 85 to 90 × 10 ⁻⁷ / ° C.

  The transparent conductive film is formed by depositing FTO (fluorine-doped tin oxide) and ITO (tin-doped indium oxide) on the glass substrate, and has a sheet resistance of about 10 to 100 Ωcm.

  The semiconductor layer made of titanium oxide may contain Sn and Zn oxides in addition to the anatase type crystal structure titanium oxide, and the titanium oxide may also contain a rutile type crystal structure. The semiconductor layer made of titanium oxide is preferably a porous film in which titanium oxide forms a net structure, preferably a through-type porous body or a porous body in which voids are connected. Is good.

  Examples of the dye to be adsorbed on the porous semiconductor layer made of titanium oxide include ruthenium bipyridine dye, azo dye, quinone dye, quinone imine dye, quinacridone dye, squarylium dye, cyanine dye, merocyanine dye, And triphenylmethane dyes, xanthene dyes, porphyrin dyes, phthalocyanine dyes, berylene dyes, indigo dyes, naphthalocyanine dyes, and the like.

Examples of the method for adsorbing the dye on the semiconductor layer include a method of immersing the semiconductor layer formed on the substrate in a solution in which the dye is dissolved (dye adsorption solution).
The solvent for dissolving the dye may be any solvent that dissolves the dye. Specifically, alcohols such as ethanol, ketones such as acetone, ethers such as diethyl ether and tetrahydrofuran, and nitrogen compounds such as acetonitrile. , Halogenated aliphatic hydrocarbons such as chloroform, aliphatic hydrocarbons such as hexane, aromatic hydrocarbons such as benzene, and esters such as ethyl acetate. Two or more of these solvents can be used in combination.
The concentration of the dye in the solution can be adjusted as appropriate depending on the type of dye and solvent to be used, but it is preferably as high as possible in order to improve the adsorption function. Since an excessively adsorbed layer is formed, a low concentration is preferable, and it may be 3 × 10 ⁻⁴ mol / liter or more.

Examples of the redox couple constituting the electrolyte include redox electrolytes such as an I ₃ ⁻ / I ⁻ system electrolyte and a Br ₃ ⁻ / Br ⁻ system electrolyte. ₃ ^- and, the reductant constituting the redox pair is I ^- / I ^- - _I ³ are based electrolyte is preferably, LiI, NaI, KI, CsI, metal iodide such as CaI _2, and A combination of iodides such as iodine salts of quaternary ammonium compounds such as tetraalkylammonium iodide, pyridinium iodide, imidazolium iodide, and I ₂ can be used.
When an electrolyte made of such an iodine-based redox solution is used in such an electrolytic solution, the positive electrode side is made of platinum or a conductive carbon material, and the catalyst particles are made of platinum or a conductive carbon material. Is preferred

  Solvents constituting the electrolyte include carbonate compounds such as ethylene carbonate and propylene carbonate; heterocyclic compounds such as 3-methyl-2-oxazolidinone; ether compounds such as dioxane and diethyl ether; ethylene glycol dialkyl ether and propylene glycol dialkyl ether , Polyethylene glycol dialkyl ether, polypropylene glycol dialkyl ether, ethylene glycol monoalkyl ether, propylene glycol monoalkyl ether, ethers such as polyethylene glycol monoalkyl ether, polypropylene glycol monoalkyl ether; alcohols such as methanol and ethanol; ethylene glycol, Propylene glycol, polyethylene glycol, poly B propylene glycol, polyhydric alcohols such as glycerin; acetonitrile, glutarodinitrile, methoxy acetonitrile, propionitrile, nitrile compounds such as benzonitrile; dimethyl sulfoxide, and the like aprotic polar substances such as sulfolane.

  The electrolyte concentration may be appropriately set depending on the type of electrolyte and solvent, and is, for example, 0.01 to 1.5 mol / liter, preferably 0.01 to 0.7 mol / liter. As an example of a specific electrolytic solution, lithium iodide is dissolved in acetonitrile so as to have concentrations of 0.06 mol / liter, iodine 0.06 mol / liter, and tertiary butylpyridine 0.3 mol / liter. Can be mentioned.

A specific method for producing a dye-sensitized solar cell is as follows.
A coating film having a thickness of 10 to 50 μm is formed by screen printing using a paste of titanium oxide powder at the center of a glass substrate on which a transparent conductive film has been formed, and this is dried in the atmosphere at 100 to 150 ° C., Bake at 400-550 ° C. for 0.5-2.0 hours.
Thereafter, a paste made of the sealing material is applied to the periphery of the glass substrate by screen printing so as to have a thickness of 50 to 200 μm, dried in the atmosphere at 100 to 150 ° C., and then at 200 to 550 ° C. A sealing layer is formed by baking for 0.5 to 2.0 hours. At this time, a titanium oxide film may be formed at a time by screen printing, and then a paste may be formed in the same manner and fired at the same time.
Thereafter, the dye is adsorbed on the titanium oxide film by dipping in a solution in which the dye is dissolved. After that, if necessary, it is immersed in a non-aqueous solvent to remove excess dye.

A glass substrate with a semiconductor layer made of titanium oxide adsorbed with a dye and a glass substrate with platinum supported on a transparent conductive film are faced and fixed, then the glass substrate is loaded and irradiated with a laser to seal Weld the layers.
After this, the electrolyte solution is introduced from the injection port formed before welding to at least one of the platinum electrode substrate side or the glass substrate on which the semiconductor layer is formed, and the injection port is closed with a mask glass etc. Type solar cell is produced.
The glass substrate on which a semiconductor layer made of titanium oxide adsorbed with a dye was adsorbed at the time of bonding and the glass substrate on which platinum was supported on a transparent conductive film faced each other and temporarily fixed using an organic material such as an ionomer, The glass substrate may be bonded by applying a load and irradiating laser light to melt the sealing layer.

  In the dye adsorption process, a glass substrate holding a titanium oxide electrode film in which a dye is adsorbed to titanium oxide by using a dipping method capable of simultaneously processing a plurality of sheets, reducing costs, and superior in quality control. In the state where the dye was not adsorbed to titanium oxide, the glass substrate was similarly bonded by laser, and the dye solution was injected from the injection port into each bonded glass cell and adsorbed to the titanium oxide film. Further, an electrolytic solution may be injected.

  In the production of this dye-sensitized solar cell, the irradiation part of the laser beam is limited to the peripheral part of the glass substrate, so that the dye-supported metal oxide semiconductor layer is not heated, and the heat deterioration of the supported dye, metal oxidation The peeling of the physical semiconductor layer from the glass substrate is prevented.

Conventionally, the method of heating the entire glass substrate in a state where two glass substrates are overlapped to melt the sealing layer to form a glass panel is employed, and thus the dye is supported after the glass panel is manufactured. There was a need. In this case, a method of injecting and circulating the dye solution into the voids inside the glass panel is performed, but satisfactory circulation of the dye solution is not possible, and it is difficult to sufficiently support the dye.
On the other hand, the above-described method does not cause such inconvenience that the pigment can be supported in the state of the glass substrate.

Specific examples are shown below.
In the joining method shown in FIG. 1, the results of detailed examination of joining conditions are shown below.
The glass substrate used was soda lime glass having a thickness of 3 mm and a 5 cm square made of Central Glass. The thermal expansion coefficient of this glass substrate was 89 × 10 ⁻⁷ / ° C. Two glass plates were used, and a joining test was performed by welding with a YAG laser.

The paste of sealing material, was used Okuno Seiyaku of _{B 2 O 3 -Bi 2 O 3} -ZnO -based low-melting glass paste. The softening point of this material was 430 ° C., and the solvent and resin were scattered by heating at a heating temperature of 400 ° C. for 20 minutes.
The thermal expansion coefficient of the paste was controlled by adding titanium oxide, magnesium oxide, aluminum oxide or the like. At this time, a mixed powder of Cr ₂ O ₃ and Fe ₂ O ₃ having an average particle size of 0.1 μm in an equal ratio as a laser absorbing component is added to the glass paste constantly so as to be 3 weight percent with respect to the glass component. Thereafter, a filler for controlling the coefficient of thermal expansion was added and adjusted. The viscosity of the paste was 95 Pa · s.

This paste was applied to the peripheral edge of the soda lime glass substrate by screen printing so as to have a width of 3 mm and a thickness of 100 μm. After coating, drying at 120 ° C. and calcination for 0.5 hours at 450 ° C. were performed. Then, it fixed so that a glass paste layer might be pinched | interposed between two glass substrates, and the joining test was done.
The laser irradiation intensity was a 35 W pulse mode with a frequency of 200 Hz, and the laser scanning speed was a constant condition of 80 mm / min. The distance from the output optical head of the YAG laser was 40 mm, and the laser beam diameter was fixed at 0.1 mmΦ.
As a result, as shown in Table 1, with respect to the thermal expansion coefficient of the glass substrate, cracks in the bonded glass substrate are reduced when the difference in the thermal expansion coefficient of the glass component in the paste is ± 10 × 10 ⁻⁷ / ° C. I solved.

In the above embodiment, as the laser absorbing component, an example of using a mixture powder of geometric of _Cr 2 _{O 3} and _Fe 2 _{O 3,} carbon black, silicon carbide powder, Fe, Cr, Mn, Ni, Metal powder such as Cu, Co, Mo, or oxide such as Fe ₃ O ₄ , NiO, CuO, Cu ₂ O, Cr ₂ O ₃ , CrO, CoO, Mn ₂ O ₃ , CoFe ₂ O ₄ , MnFe ₂ O ₄ Similar effects were obtained with powders such as powder, CuSO ₄ , NiSO ₄ , CoCl ₂ , and MnCO ₃ .
As a comparative example, it was not possible to heat without using these laser-absorbing components.

In the above example, the laser absorbing component was added to the paste, but the coating film of the ferric oxide was formed on the glass substrate to a thickness of about 0.1 μm by the spray method, and the heat with the glass substrate was formed thereon. A test was performed by changing the paste composition so that the difference in expansion coefficient was ± 10 × 10 ⁻⁷ / ° C., but the same effect was obtained.
At this time, no laser absorbing component was added to the paste. In addition to this ferric oxide, similar effects can be obtained with Fe ₃ O ₄ , NiO, CuO, Cu ₂ O, Cr ₂ O ₃ , CrO, CoO, Mn ₂ O _3, etc. Also, Cu, Ni made by Sumitomo Metal Mining The same effect was confirmed with powder and Fe powder manufactured by Toda Kogyo.

Next, in the above example, when the glass substrates were joined by laser, evaluation was performed by changing only the laser power.
The difference in thermal expansion coefficient of the glass component of the paste is 2 × 10 ⁻⁷ / ° C. with respect to the thermal expansion coefficient of the glass substrate, and Cr ₂ O ₃ is 3 weight percent in solid content as the laser absorption component. Added. Other conditions were the same.
The test results are shown in Table 2 below. From this result, the power applied to the area of 0.1 mmΦ is preferably 20-80 W, and the power density per unit area is preferably 3 × 10 ⁵ to 1 × 10 ⁶ W / cm ^2. I understood.

  Next, evaluation was performed by changing the laser oscillation mode when laser irradiation was performed. At this time, the laser power was fixed at 50 W, and the comparison was made between the continuous oscillation mode and the pulse mode. In the pulse mode, the scanning was performed in the range of 10 Hz to 10 kHz, and the scanning speed was fixed at 50 mm / min. Moreover, the distance from the laser head to the bonded portion of the glass substrate was changed, and the beam diameter was set to 70 μmΦ. As assist gas, air was sprayed from the vicinity of the head toward the substrate side at 10 L / min. As a result, it was found that in the continuous oscillation mode, the glass substrate is easily cracked when fused and bonded. When the pulse mode is set to a low frequency, it becomes a state close to laser spot welding and a dense seal cannot be obtained. Therefore, at least a numerical value Φ × f obtained by multiplying the laser beam diameter Φ by the frequency f is a laser scanning speed (mm / sec). ) Was found to be larger than

When laser irradiation was performed in the bonding method shown in FIG. 2, a test was performed to check the bonding state by applying temperature to the glass substrate with a hot plate.
The difference in thermal expansion coefficient of the glass component of the paste with respect to the thermal expansion coefficient of the glass substrate is 8 × 10 ⁻⁷ / ° C., and Cr ₂ O ₃ is 3 weight percent in solid content as a laser absorption component. Added. The laser power was 50 W, and the power density per unit area was 0.64 × 10 ⁶ W / cm ² . Other conditions were the same. The temperature condition by the hot plate was in the range of room temperature to 300 ° C.
The test results are shown in Table 3 below. As a result, it was found that there is an effect of reducing cracks during joining when the temperature rises.

Next, a test was performed to confirm the bonding state by applying a load to the glass substrate when laser irradiation was performed. To thermal expansion of the glass substrate, the difference in thermal expansion coefficient of the glass component of the laser absorbing sealing glass paste to 2 × 10 -7 ^/ ℃, 3 weight in solid content Cr ₂ O ₃ as a laser absorbing material It added so that it might become a percentage. The laser power was 80 W, and the power density per unit area was 1 × 10 ⁶ W / cm ² . Other conditions were the same.
The loading conditions, so as to apply a predetermined load by a prism over a glass substrate as shown in FIG. 3, and the per unit area 1 gf / cm ² and a load range of 100 gf / cm ^2.
The test results are shown in Table 4 below. As a result, it was found that when there is a load, the bonding strength is improved. In particular, it was remarkably improved by setting it to 20 gf / cm ² or more. When evaluated as the pressure applied to the wiring at this time, it was found that 83 gf / cm ² or more is preferable.

Next, a dye-sensitized solar cell was prototyped and evaluated.
Soda lime glass having a thickness of 3 mm and 5 cm square was used as the soda lime glass plate used in the cell. The thermal expansion coefficient of this glass plate was 88 × 10 ⁻⁷ / ° C. An ITO transparent conductive film having a thickness of 1 μm was formed on this soda lime glass plate by spraying, and baked at 450 ° C. for 1 hour in the air. One glass substrate on which this transparent conductive film was formed was formed into a Pt film having a thickness of 30 nm by a sputtering method, and holes with a diameter of 1 mmΦ were formed at two opposite ends in a diagonal direction by a drill.

  Another glass substrate with a transparent conductive film formed thereon was coated with a paste of titanium oxide P25 (Degussa, trade name: “P25”) with a thickness of 30 μm by screen printing. At this time, printing was performed so that a portion of 5 mm from the peripheral edge of the glass plate was not attached with the titanium oxide paste. The paste of titanium oxide P25 used was terpione added with 70% by weight as a solid concentration. The paste was applied to the peripheral edge portion by screen printing so that the thickness was 100 μm from the end to a portion of 3 mm.

The paste obtained by the thermal expansion coefficient 84 × ^{10 -7} / ℃ by adding 1% by weight of NiO into _P 2 _O 5 -SnO-based manufactured by Toyo Glass _{P 2 O} 5 _-WO 3 -ZrO 2 filler Was used.
Next, the glass substrate coated with the titanium oxide film was dried at 120 ° C. in the atmosphere and baked at 500 ° C. for 1 hour. Thereafter, a ruthenium complex dye: ruthenium 535 (SOLARAONIX product name: ruthenium 535) was immersed in an ethanol solution having a concentration of 5 × 10 ⁻⁴ mol / liter and held for 8 hours. Excess dye was removed by immersion in absolute ethanol and dried at 100 ° C.

Using this glass plate adsorbed with the dye, another glass plate on which a platinum film was formed was faced and a sealing layer made of paste was sandwiched between the two glass plates.
A load of 50 gf / cm ² was applied to the ^two glass plates, and irradiation was performed at 1 × 10 6 W / cm ² as a laser power density in a unit area. At this time, a YAG laser was used as the laser at a pulse mode of 100 Hz, and the scanning speed was 80 mm / min.

Acetonitrile electrolyte solution to produce the cells were dissolved LiI and I ₂ were placed from the inlet, and injected to be uniform throughout the cell. The photoelectric conversion characteristics of this sample were examined.
As a comparative example, a 60 μm ionomer (spacer S (trade name: “Hi-Millan” manufactured by Mitsui DuPont Polychemicals)) fused without using a laser and fused at 120 ° C. is used. It was.
Short-circuit current density (Jsc), open-circuit voltage (Voc), fill factor (FF), and energy conversion efficiency (η (%)) of the cell prepared by the method of the present invention and the dye-sensitized solar cell of the comparative example Was measured.

In addition, the energy conversion efficiency ((eta) (%)) of a dye-sensitized solar cell is represented by following formula (1). Here, in the following formula (1), Po is the incident light intensity [mWcm ⁻² ], Voc is the open circuit voltage [V], Jsc is the short circuit current density [mA · cm ⁻² ], F.V. F. Indicates a fill factor.
η = 100 × (Voc × Jsc × FF) / Po (1)

The battery characteristic evaluation test was performed using a solar simulator (trade name: “YSS-100A type” manufactured by Yamashita Denso Co., Ltd.) and the irradiation condition of pseudo-sunlight from a xenon lamp light source through an AM filter (AM1.5) was 100 mW. / Cm ² (so-called “1Sun” irradiation condition). The results of photoelectric conversion efficiency are shown in Table 5.

  Next, using these two samples, they were placed in a constant temperature bath at 85 ° C. and held for one week. As a result, in the sample sealed with ionomer, the electrolyte solution leaked to the outside and was depleted, but in the sample fixed with the laser-absorbing sealing glass paste of the present invention, no change was observed in appearance.

Next, as a dye-sensitized solar battery cell, evaluation was performed by making a prototype with a joining form as shown in FIG. 4 by joining with an ionomer and a laser.
As the soda lime glass plates 1 and 2 used in the cell, soda lime glass having a thickness of 3 mm and 5 cm square was used. The thermal expansion coefficient of this glass plate was 89 × 10 ⁻⁷ / ° C. An ITO transparent conductive film having a thickness of 10 μm was formed on this soda lime glass plate by screen printing, and baked at 450 ° C. for 1 hour in the air. One glass substrate 2 on which the transparent conductive film was formed was formed into a Pt film with a thickness of 300 nm by a sputtering method, and holes with a diameter of 1 mmΦ were formed at four corner positions by a drill.

  On the glass substrate 1 on which another transparent conductive film was formed, a titanium oxide P25 paste was applied thereon to a thickness of 20 μm by screen printing. At this time, printing was performed so that the titanium oxide paste was not attached to a portion 6 mm from the peripheral edge of the glass plate. The paste of titanium oxide P25 used was terpione added with 70% by weight as a solid concentration. The paste was applied to the peripheral edge portion by screen printing so that the thickness was 100 μm from the end to a portion of 3 mm.

As a paste, 1 weight percent of CuO is added to the SiO ₂ —CaO—Na (K) ₂ O system, and the softening point is changed depending on the amount of Na ₂ O added, and the coefficient of thermal expansion is increased depending on the amount of Al ₂ O ₃ filler added. 84 × 10 ⁻⁷ / ° C. was used. Next, the glass substrate coated with the titanium oxide paste was dried at 120 ° C. in the air and baked at 500 ° C. for 1 hour. By this firing, the paste is temporarily fired, and the sealing layer 3 and the titanium oxide paste are fired to form the semiconductor layer 8.
Thereafter, the ruthenium complex dye ruthenium 535 (SOLARAONIX product name: ruthenium 535) was immersed in a solution having a concentration of 5 × 10 ⁻⁴ mol / liter and held for 8 hours. Excess dye was removed by immersion in absolute ethanol and dried at 100 ° C.

An ionomer seal 7 having a thickness of 60 μm and a width of 3 mm is placed inside 3 mm from the outside on the glass substrate on which Pt is formed by sputtering with these two glass plates, and the outside sealing layer 3 is sandwiched between them. And a load of 100 gf / cm ² was applied. In this state, heat fusion was performed at 120 ° C. with an ionomer. Subsequently, by applying a load of 50 gf / cm ² on the glass plate of the two, as the laser power density on a unit area, were irradiated with ^{1 × 10 6 W / cm 2} . At this time, the YAG laser was used as the laser at a pulse mode of 300 Hz, and the scanning speed was 80 mm / min.

Acetonitrile electrolyte solution 9 to produce the cells were dissolved LiI and I ₂ put from the inlet, and injected to be uniform throughout the cell. The photoelectric conversion characteristics of this sample were examined. As a comparative example, a material fused at 120 ° C. so as to have the same shape using a 60 μm ionomer without using the above laser was used.
The results of photoelectric conversion efficiency are shown in Table 6 below.

  Using these two samples, they were placed in a constant temperature bath at 85 ° C. and held for one week. As a result, in the sample sealed with ionomer, the electrolyte leaked to the outside and was depleted, but in the sample fixed with the ionomer and the laser-absorbing sealing glass paste of the present invention, no change in appearance was seen. It was.

It is a schematic block diagram which shows the 1st example of the manufacturing method of this invention. It is a schematic block diagram which shows the 2nd example of the manufacturing method of this invention. It is a schematic block diagram which shows the 3rd example of the manufacturing method of this invention. It is a schematic block diagram of the dye-sensitized solar cell created with the manufacturing method of this invention.

Explanation of symbols

1 ·· First glass substrate 2 ·· Second glass substrate 3 ·· Sealing layer 31 ·· Outside sealing layer 4 ·· Laser head 5 ·· Hot plate 6 ·· Weight Element

Claims (3)

The difference in thermal expansion coefficient between the laser-absorbing component consisting of one or more of chromium, iron, nickel, cobalt, manganese, copper, and carbon and a glass component, and a sealed member made of glass is 10 Sealing material that is × 10 ⁻⁷ / ° C. or lower.   A sealing layer made of the sealing material according to claim 1 is formed on a sealing portion of at least one glass substrate, the other glass substrate is overlaid, and the sealing layer is irradiated with laser light to seal the sealing layer. A method for producing a glass panel, comprising melting two pieces and joining two glass substrates. On one of the glass substrates, a transparent conductive film and a dye-supported metal oxide semiconductor layer on the transparent conductive film are formed on the inner surface.
A dye-sensitized solar cell produced by the production method according to claim 2, wherein the other glass substrate has a conductive film formed on the inner surface thereof.

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