JP2011057477A - Sealing material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the airtightness and reliability of an organic EL display, etc. while preventing the thermal deteriorations of active elements, etc. by originating a sealing material having good light absorption characteristics and good thermal stability. <P>SOLUTION: The sealing material includes 70-99.9 vol.% of the total amount of glass powder and fireproof filler powder and furthermore 0.1-20 vol.% of transition metal oxide powder in the sealing material containing the glass powder and fireproof filler powder. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a sealing material, and more particularly to a sealing material suitable for sealing with a laser beam or the like.

  Organic EL displays are attracting attention as next-generation flat display panels. Since the organic EL display can be driven by a DC voltage, the driving circuit can be simplified, and there are advantages such as a liquid crystal display that is not dependent on the viewing angle, bright due to self-emission, and has a high response speed. Currently, organic EL displays are mainly used in small portable devices such as mobile phones, but in the future, application to ultra-thin televisions is expected.

  The organic EL display is composed of two glass substrates, a negative electrode such as metal, an organic light emitting layer, a positive electrode such as ITO, and an adhesive material. The organic EL display is mainly driven by disposing an active element such as a thin film transistor (TFT) in each pixel in the same manner as a liquid crystal display. In this case, non-alkali glass is used as a glass substrate. Is done.

  Conventionally, an organic resin such as an epoxy resin having a low temperature curing property or an ultraviolet curable resin has been used as an adhesive material. However, since the organic resin cannot completely block gas intrusion, it is difficult to maintain the airtightness inside the organic EL display. For this reason, when an organic resin is used, the display characteristics of the organic EL display deteriorate over time. Moreover, although organic resin has the advantage which can adhere | attach glass substrates at low temperature, it has the fault that water resistance is low. For this reason, when an organic resin is used, the problem that the reliability of an organic electroluminescent display falls by long-term use also arises. In addition, organic EL devices, such as organic EL illumination, are equipped with the same structure, and have the same technical subject.

US Pat. No. 6,416,375 JP 2006-315902 A

  The sealing material containing glass powder can maintain the airtightness inside the organic EL display over a long period of time, and is excellent in water resistance. Therefore, when the sealing material containing glass powder is used instead of the organic resin, the above problem can be solved.

  However, since the sealing material generally has a softening point of glass powder of 300 ° C. or higher, it is difficult to apply it to an organic EL display. The reason is that in order to seal the glass substrates together, it is necessary to put the entire organic EL display in an electric furnace or the like and heat-treat at a temperature equal to or higher than the softening point of the glass powder. This is because the layer is thermally deteriorated.

  In view of such circumstances, in recent years, methods for sealing organic EL displays by irradiating sealing materials with irradiation light such as laser light have been studied. When laser light or the like is used, only the portion to be sealed can be locally heated, so that the glass substrates can be sealed together while preventing thermal degradation of the active element or the like. For example, Patent Documents 1 and 2 describe that a sealing material is irradiated with laser light to seal a front glass substrate and a back glass substrate of a field emission display.

  However, Patent Documents 1 and 2 do not describe a material configuration suitable for local heating by laser light or the like, and cannot find guidelines for material development. In addition, in order to enhance the light absorption characteristics of the sealing material, a method of adding a light absorbing component to the glass composition of the glass powder is also under investigation, but considering the component balance of the glass composition, the amount of light absorbing component added Is limited, and it may be difficult to sufficiently enhance the light absorption characteristics of the sealing material. Furthermore, depending on the glass composition system, when a light absorbing component is added in the glass composition, the component balance of the glass composition is impaired, the thermal stability of the glass is lowered, and the sealing process may not be performed properly. .

  Therefore, the present invention creates a sealing material that has good light absorption characteristics and good thermal stability, thereby preventing thermal degradation of active elements and the like, while preventing air deterioration of organic EL displays and the like. Increasing reliability is a technical issue.

  As a result of diligent efforts, the present inventors have found that the above technical problem can be solved by adding a predetermined amount of transition metal oxide powder to the sealing material, and propose the present invention. That is, the sealing material of the present invention is a sealing material containing glass powder and refractory filler powder, and contains glass powder and refractory filler powder in a total amount of 70 to 99.9% by volume, and further transition metal oxidation It contains 0.1 to 20% by volume of powdered product.

  The sealing material of this invention contains 70-99.9 volume% of glass powder and a refractory filler powder in a total amount. In this way, the airtightness inside the organic EL display can be maintained. Note that the sealing material of the present invention does not completely exclude the embodiment that does not contain the refractory filler powder, but as described later, for the purpose of reducing the thermal expansion coefficient and improving the mechanical strength, the refractory filler is used. It is preferable to contain a powder.

  As a result of intensive investigations, the present inventors have significantly improved the light absorption characteristics of the sealing material without significantly reducing the thermal stability of the glass if a transition metal oxide powder is added to the sealing material. I found out that I can do it. That is, the sealing material of this invention contains 0.1-20 volume% of transition metal oxide powder as an essential component. When transition metal oxide powder is added to the sealing material, light energy such as laser light can be efficiently converted into thermal energy, so only the part to be sealed can be locally heated, resulting in active elements, etc. The glass substrates can be sealed with each other while preventing thermal degradation. Addition of the transition metal oxide powder increases the degree of freedom in designing the composition of the glass powder, and as a result, it is easy to increase the thermal stability of the glass. On the other hand, the sealing material of the present invention regulates the content of the transition metal oxide powder to 20% by volume or less. If it does in this way, the situation where glass devitrifies at the time of glaze baking or irradiation can be prevented.

  Secondly, the sealing material of the present invention is characterized in that the transition metal oxide powder is CuO. Since CuO has excellent light absorption characteristics among transition metal oxides, it can efficiently convert light energy such as laser light into heat energy.

Third, the sealing material of the present invention, the transition metal oxide average particle diameter D ₅₀ of the powder is characterized in that it is 5μm or less. Here, the “average particle diameter D ₅₀ ” represents a particle diameter in which the accumulated amount is 50% cumulative from the smaller particle in the volume-based cumulative particle size distribution curve measured by the laser diffraction method.

Fourth, the sealing material of the present invention is characterized in that the maximum particle diameter D _max of the transition metal oxide powder is 30 μm or less. Here, the “maximum particle diameter D _max ” represents a particle diameter in which the accumulated amount is 99% cumulative from the smaller particle in the volume-based cumulative particle size distribution curve measured by the laser diffraction method.

Fifth, in the sealing material of the present invention, the glass powder is Bi ₂ O ₃ —B ₂ O ₃ glass, Bi ₂ O ₃ —SiO ₂ glass, ZnO—B ₂ O ₃ —SiO ₂ glass, It is either V ₂ O ₅ —P ₂ O ₅ glass or SnO—P ₂ O ₅ glass.

  Sixth, the sealing material of the present invention is characterized in that the glass powder contains 0.1 mol% or more of a transition metal oxide as a glass composition. By doing so, since the laser beam or the like is also absorbed by the glass, the light absorption characteristics of the sealing material are improved.

  Seventh, the sealing material of the present invention is characterized in that the content of the refractory filler powder is 0.1 to 75% by volume. In this way, the thermal expansion coefficient of the sealing material can be easily matched with the thermal expansion coefficient of the object to be sealed, and the mechanical strength of the sealed portion is improved.

  Eighth, the sealing material of the present invention is a kind in which the refractory filler powder is selected from cordierite, willemite, alumina, zirconium tungstate phosphate, zirconium tungstate, zirconium phosphate, zircon, zirconia, and tin oxide. Or it is characterized by being 2 or more types.

Ninth, the sealing material of the present invention has an average particle diameter D ₅₀ of the refractory filler powder and less than 15 [mu] m.

Tenth, the sealing material of the present invention is characterized in that the maximum particle diameter _Dmax of the refractory filler powder is 30 μm or less.

  Eleventh, the sealing material of the present invention is characterized by being used for sealing with irradiation light. In this way, the sealing material can be locally heated, and thermal deterioration of a member having low heat resistance (for example, an active element, an organic light emitting layer, an organic dye, etc.) can be prevented.

Twelfth, the sealing material of the present invention is characterized in that the irradiation light is laser light. Various laser beams can be used as the laser beam. In particular, a semiconductor laser, a YAG laser, a CO ₂ laser, an excimer laser, an infrared laser, and the like are preferable in terms of easy handling. In addition, in order to make a sealing material absorb a laser beam exactly, the emission center wavelength of a laser beam is 500-1600 nm, Especially 750-1300 nm is preferable.

  Thirteenth, the sealing material of the present invention is characterized in that the irradiation light is infrared light. In this way, the sealing material can be locally heated over a wide range, and as a result, the production efficiency of the organic EL device and the like is improved.

Fourteenth, the sealing material of the present invention has a thermal expansion coefficient of 75 × 10 ⁻⁷ / ° C. or less. Here, the “thermal expansion coefficient” refers to a value measured with a push rod type thermal expansion coefficient measurement (TMA) apparatus, and the measurement temperature range is 30 to 300 ° C.

  15thly, the sealing material of this invention is characterized by not containing PbO substantially. Here, “substantially does not contain PbO” refers to a case where the content of PbO in the sealing material is 1000 ppm or less. In this way, environmental demands in recent years can be satisfied.

  Sixteenth, the sealing material of the present invention is used for sealing organic EL devices or solar cells.

  In the sealing material of the present invention, the total content of the glass powder and the refractory filler powder is 70 to 99.9% by volume, 80 to 99.9% by volume, 90 to 99.5% by volume, particularly 95. -99 volume% is preferable. When the total content of the glass powder and the refractory filler powder is less than 70% by volume, it is difficult to ensure airtightness of the organic EL display or the like. On the other hand, if the total content of the glass powder and the refractory filler powder is more than 99.9% by volume, the content of the transition metal oxide powder is reduced, so that the light absorption characteristics of the sealing material are lowered, and the laser It becomes difficult to convert light energy such as light into heat energy.

  In the sealing material of the present invention, the content of the transition metal oxide powder is 0.1 to 20% by volume, preferably 0.5 to 10% by volume, more preferably 1 to 5% by volume. When the content of the transition metal oxide powder is less than 0.1% by volume, the light absorption property of the sealing material is lowered, and it becomes difficult to convert light energy such as laser light into heat energy. On the other hand, when the content of the transition metal oxide powder is more than 20% by volume, the thermal stability of the sealing material is lowered, and the fluidity of the sealing material is also lowered. As a result, the sealing strength is lowered. It becomes easy.

In addition, various transition metal oxides (for example, CuO, Fe ₂ O ₃ , NiO, V ₂ O ₅ , CoO, TiO ₂ , MoO ₃ , MnO _2, etc.) can be used as the transition metal oxide powder. Among these, CuO is particularly preferable. CuO easily diffuses into the glass as Cu ²⁺ at the time of glaze firing or irradiation, and furthermore, since absorption in the infrared region is large, light energy such as laser light can be efficiently converted into heat energy.

In the sealing material of the present invention, the transition metal oxide average particle diameter _{D 50} of the powder 5μm or less, 0.01 to 5 [mu] m, 0.5 to 4 .mu.m, particularly 1~3μm is preferred. A transition metal oxide average particle diameter D ₅₀ of the powder 0.01μm smaller, when glaze firing or during irradiation, the transition metal oxide powder is easily dissolved into a glass, the thermal stability of the sealing material tends to decrease Become. Meanwhile, a possibility that the transition metal oxide average particle diameter D ₅₀ of the powder and 5μm greater than it is difficult to uniformly disperse the transition metal oxide powder in the sealing material, locally sealing failure occurs There is.

In the sealing material of the present invention, the maximum particle diameter _Dmax of the transition metal oxide powder is preferably 30 μm or less, 20 μm or less, particularly preferably 10 μm or less. When the maximum particle diameter D _max of the transition metal oxide powder is 30 μm or less, the sealing thickness is easily reduced. In this case, even if the difference in the thermal expansion coefficient between the glass substrate and the sealing material is large, the glass substrate and Cracks and the like are less likely to occur at the sealing site. On the other hand, when the maximum particle diameter _Dmax of the transition metal oxide powder is larger than 30 μm, a part of the transition metal oxide powder is easily exposed on the glaze surface, so that it is difficult to make the gap between the glass substrates uniform.

Various glasses can be used as the glass powder. In particular, Bi ₂ O ₃ —B ₂ O ₃ glass, Bi ₂ O ₃ —SiO ₂ glass, ZnO—B ₂ O ₃ —SiO ₂ glass, V ₂ O ₅ —P ₂ O ₅ glass, SnO— P ₂ O ₅ -based glass is preferable because it has low melting point characteristics and good thermal stability. Here, “to glass” includes an explicit component as an essential component, and the total content of the explicit component is 30 mol% or more, preferably 40 mol% or more, more preferably 50 mol% or more. Refers to the case.

Bi ₂ O ₃ -B ₂ O ₃ based glass, a glass composition, in _{mol%, Bi 2 O 3 15~50%} , B 2 O 3 15~50%, ZnO 0~45% ( preferably 1 to 40 %) Is preferable. In this way, it is possible to achieve both a low melting point characteristic and thermal stability at a high level. In particular, in order to improve thermal stability, it is preferable to add 0.1 mol% or more of BaO in the glass composition.

Bi ₂ O ₃ —SiO ₂ -based glass preferably contains 15% to 50% Bi ₂ O ₃ , 10% to 35% B ₂ O _{3, and} 0.5% to ₃₀ % SiO ₂ as a glass composition. . In this way, thermal stability, low melting point characteristics and water resistance can be achieved at a high level.

The ZnO—B ₂ O ₃ —SiO ₂ -based glass preferably contains, as a glass composition, mol%, SiO ₂ 20 to 50%, B ₂ O ₃ 15 to 35%, and ZnO 1 to 45%. In this way, thermal stability and low expansion characteristics can be achieved at a high level. In particular, in order to lower the melting point, it is preferable to add 0.1 mol% or more of an alkali metal oxide (Li ₂ O, Na ₂ O, K ₂ O) in the glass composition.

V ₂ O ₅ -P ₂ O ₅ based glass, a glass composition, in _{mol%, V 2 O 5 25~55%} , preferably contains _P 2 O 5 _15~45%. In this way, both thermal stability and low melting point characteristics can be achieved at a high level. _{Incidentally, V 2 O 5 -P 2 O} 5 based _glass, since V 2 _{O 5} has a light absorbing property, it is possible to increase the light absorption properties of the sealing material.

The SnO—P ₂ O ₅ -based glass preferably contains SnO 35 to 70% and P ₂ O ₅ 18 to 50% (preferably 20 to 30%) as a glass composition in mol%. In this way, both thermal stability and low melting point characteristics can be achieved at a high level. In addition, in order to improve thermal stability, it is preferable to add ZnO 1 mol% or more in a glass composition.

In each glass system, in addition to the above components, it is preferable to add a transition metal oxide in the glass composition in an amount of 0.1 mol% or more, 0.1 to 10 mol%, particularly 0.5 to 5 mol%. If a transition metal oxide is added to the glass composition, conversion to thermal energy can be promoted upon irradiation with laser light or the like. The transition metal oxide is preferably CuO, Fe ₂ O ₃ , NiO, V ₂ O ₅ , CoO, TiO ₂ , MoO ₃ , MnO ₂ or the like. These transition metal oxides have good light absorption characteristics and can enhance the thermal stability of the glass.

  As described above, it is preferable that the sealing material of the present invention does not substantially contain PbO from the environmental viewpoint.

In the sealing material of the present invention, the content of the refractory filler powder is preferably 0.1 to 75% by volume, 20 to 70% by volume, 25 to 65% by volume, 30 to 60% by volume, particularly 35 to 55% by volume. .
If the refractory filler powder is added, the thermal expansion coefficient of the sealing material can be easily matched with the thermal expansion coefficient of the object to be sealed, and it is possible to prevent a situation in which an undue stress remains in the sealed portion. Moreover, if a refractory filler powder is added, the mechanical strength of the sealing part can be increased. However, if the content of the refractory filler powder is more than 75% by volume, the content of the glass powder as the flux is relatively reduced, so that the fluidity of the sealing material is lowered and the sealing strength is lowered. It becomes easy. In particular, when the material to be sealed is alkali-free glass, the content of the refractory filler powder is preferably 40% by volume or more, particularly 50% by volume or more. If it does in this way, it will become easy to match the thermal expansion coefficient of sealing material with thermal expansion coefficients, such as an alkali free glass.

  In the sealing material of the present invention, the refractory filler powder is one or more selected from cordierite, willemite, alumina, zirconium tungstate phosphate, zirconium tungstate, zirconium phosphate, zircon, zirconia, tin oxide. Is preferred. These refractory filler powders have high mechanical strength and good compatibility with glass powders in addition to a low coefficient of thermal expansion. In addition to the above refractory filler powder, refractory filler powder such as quartz glass and β-eucryptite should be added to adjust the coefficient of thermal expansion, adjust fluidity and improve mechanical strength. Can do.

In the sealing material of the present invention, the average particle diameter D50 of the glass powder is preferably less than 15 μm, 0.5 to 10 μm, and particularly preferably 1 to ₅ μm. When the average particle diameter D ₅₀ of the glass powder is smaller than 15 [mu] m, the softening point of the glass powder is lowered, with increases flowability of the sealing material, it tends to narrow the sealing thickness, in this case, the glass substrate and the sealing Even if the difference in the thermal expansion coefficients of the adhesive materials is large, cracks and the like are unlikely to occur in the glass substrate and the sealing part.

In the sealing material of the present invention, the maximum particle diameter _Dmax of the glass powder is preferably 30 μm or less, 20 μm or less, and particularly preferably 10 μm or less. When the maximum particle diameter _Dmax of the glass powder is 30 μm or less, the softening point of the glass powder is lowered, the fluidity of the sealing material is increased, and the sealing thickness is easily narrowed. Even if the difference in the thermal expansion coefficients of the adhesive materials is large, cracks and the like are unlikely to occur in the glass substrate and the sealing part.

In the sealing material of the present invention, the average particle diameter D50 of the refractory filler powder is preferably less than 15 μm, 0.5 to 10 μm, and particularly preferably 1 to ₅ μm. When the average particle diameter D ₅₀ of the refractory filler powder is less than 15 μm, the sealing thickness can be reduced. In this case, even if the difference in thermal expansion coefficient between the glass substrate and the sealing material is large, the glass substrate and Cracks and the like are less likely to occur at the sealing site. On the other hand, when the average particle diameter D ₅₀ of the refractory filler powder is 15μm or more, sealing portion becomes thick, it becomes difficult to thin the organic EL display or the like. Incidentally, the refractory filler powder effects (e.g., effect of reducing the thermal expansion coefficient of the sealing material) in order to accurately receive the average particle diameter D ₅₀ of the refractory filler powder is preferably at least 0.5 [mu] m.

In the sealing material of the present invention, the maximum particle diameter _Dmax of the refractory filler powder is preferably 30 μm or less, 20 μm or less, and particularly preferably 10 μm or less. When the maximum particle diameter _Dmax of the refractory filler powder is 30 μm or less, the sealing thickness can be reduced. In this case, even if the difference in thermal expansion coefficient between the glass substrate and the sealing material is large, the glass substrate and Cracks and the like are less likely to occur at the sealing site. On the other hand, when the maximum particle diameter _Dmax of the refractory filler powder is larger than 30 μm, a part of the refractory filler powder is easily exposed from the glaze surface, so that it is difficult to make the gap between the glass substrates uniform.

In the sealing material of the present invention, the thermal expansion coefficient is preferably 75 × 10 ⁻⁷ / ° C. or less, 65 × 10 ⁻⁷ / ° C. or less, 55 × 10 ⁻⁷ / ° C. or less, and particularly preferably 50 × 10 ⁻⁷ / ° C. or less. . When the thermal expansion coefficient of the sealing material is lowered, if the thermal expansion coefficient of the object to be sealed is low, the stress remaining in the object to be sealed or the sealing part can be reduced. And it becomes easy to prevent the situation where airtightness, such as an organic EL display, is impaired. In particular, when the material to be sealed is alkali-free glass (thermal expansion coefficient: about 38 × 10 ⁻⁷ / ° C.), the thermal expansion coefficient of the sealing material is preferably 10 to 55 × 10 ⁻⁷ / ° C.

  In the sealing material of the present invention, the softening point is preferably 550 ° C. or lower, 500 ° C. or lower, particularly 465 ° C. or lower. When the softening point is higher than 550 ° C., the glass powder tends to be difficult to soften even when irradiated with laser light or the like. In order to increase the sealing strength, the output of laser light or the like must be increased. Production efficiency of an EL display or the like tends to decrease. The lower limit of the softening point is not particularly limited, but considering the thermal stability of the glass powder, the softening point is preferably 350 ° C. or higher, particularly 385 ° C. or higher. Here, the “softening point” refers to a value measured with a differential thermal analyzer (DTA), the measurement is performed in air, and the rate of temperature rise is 10 ° C.

  The sealing material of the present invention may further contain up to 10% by volume of glass fiber, glass beads, silica beads, resin beads and the like as spacers in order to make the sealing thickness uniform.

  The sealing material of the present invention may be used as it is in powder form, but it becomes easy to handle when it is uniformly kneaded with a vehicle and processed into a paste. The vehicle mainly includes a solvent and a resin binder, and the resin binder is added for the purpose of adjusting the viscosity of the paste. Moreover, surfactant, a thickener, etc. can also be added as needed. The produced paste is usually applied to a glass substrate or the like using an applicator such as a dispenser or a screen printer, and then subjected to a binder removal step.

  As the resin binder, acrylic acid ester (acrylic resin), ethyl cellulose, polyethylene glycol derivative, nitrocellulose, polymethylstyrene, polyethylene carbonate, methacrylic acid ester and the like can be used.

  As the solvent, N, N′-dimethylformamide (DMF), α-terpineol, higher alcohol, γ-butyllactone (γ-BL), tetralin, butyl carbitol acetate, ethyl acetate, isoamyl acetate, diethylene glycol monoethyl ether, Diethylene glycol monoethyl ether acetate, benzyl alcohol, toluene, 3-methoxy-3-methylbutanol, triethylene glycol monomethyl ether, triethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, triethylene glycol Propylene glycol monobutyl ether, propylene carbonate, dimethyl sulfoxide (DMSO), N-me -2-pyrrolidone and the like can be used. In particular, α-terpineol is preferable because it has high viscosity and good solubility in a resin binder and the like.

  The sealing material of the present invention is preferably used for sealing an organic EL device. The reason is that since the organic EL device includes a member having poor heat resistance and water resistance, it is highly necessary to perform a sealing treatment with irradiation light. In particular, there is a great need for organic EL displays and organic EL lighting.

The sealing material of the present invention is preferably used for sealing solar cells, and more preferably used for sealing dye-sensitized solar cells. Dye-sensitized solar cells developed by Gretcher et al. Are expected as next-generation solar cells. The dye-sensitized solar cell includes a transparent electrode substrate on which a transparent conductive film is formed, and a porous oxide semiconductor electrode composed of a porous oxide semiconductor layer (mainly a TiO ₂ layer) formed on the transparent electrode substrate, An organic dye such as a Ru dye adsorbed on the porous oxide semiconductor electrode, an iodine electrolyte containing iodine, a counter electrode substrate on which a catalyst film and a transparent conductive film are formed, and the like. When the sealing material of the present invention is used in a dye-sensitized solar cell, gas intrusion can be completely blocked, so that a situation in which iodine electrolyte leaks from the solar cell can be prevented while preventing deterioration of battery characteristics. Can do. In addition, when the sealing material of the present invention is used for a dye-sensitized solar cell, it can be used for sealing treatment with irradiation light, so that the transparent electrode substrate can be used after preventing thermal deterioration of components such as organic dyes. And the counter electrode substrate can be sealed.

  Hereinafter, the present invention will be described in detail based on examples.

  Table 1 shows an example (sample No. 1 to 3) and a comparative example (sample No. 4) of the present invention.

Each sample shown in Table 1 was prepared as follows. First, a glass batch in which raw materials such as various oxides and carbonates were prepared so as to have the glass composition in the table was prepared, and the glass batch was put in a platinum crucible and melted at 1100 ° C. for 1 hour. Next, the molten glass was formed into a thin piece with a water-cooled roller. Finally, after grinding the flaky glass ball mill, and air classification, the average particle diameter _{D 50} of 2.5 [mu] m, maximum particle diameter _{D max} to obtain each glass powder of 20 [mu] m.

CuO was used as the transition metal oxide powder. CuO has an average particle diameter _{D 50} of 3.0 [mu] m, maximum particle diameter _{D max} was prepared so as to 20 [mu] m.

Cordierite was used as the refractory filler powder. Cordierite, an average particle diameter _{D 50} of 2.5 [mu] m, maximum particle diameter _{D max} was prepared so as to 20 [mu] m.

  As shown in the table, the glass powder, the refractory filler powder and the transition metal oxide powder were mixed, and the sample no. 1-4 were produced. Sample No. About 1-4, the glass transition point, the softening point, the thermal expansion coefficient, and the possibility of joining were evaluated.

  The glass transition point and softening point were measured with a DTA apparatus. The measurement was performed in the atmosphere at a temperature rising rate of 10 ° C./min, and the measurement was started from room temperature.

  The thermal expansion coefficient was measured with a TMA apparatus. The measurement temperature range was 30 to 300 ° C. In addition, the measurement sample used what each sample sintered precisely.

  The possibility of joining was evaluated as follows. First, each sample and an ethylcellulose-based vehicle were kneaded and prepared so as to have a viscosity of about 150 Pa · s, and then kneaded uniformly with a three-roll mill to form a paste. This paste was printed and applied to the center of a strip-shaped glass substrate so that the line width was 0.8 mm × length 4 mm × thickness 20 μm, and then dried at 120 ° C. for 30 minutes in a drying oven. Next, baking was performed for 120 minutes at the softening point shown in the table, and the resin component contained in the vehicle was debindered to obtain a glaze film. During firing, the temperature raising / lowering rate was 10 ° C./min. Subsequently, after accurately overlapping a glass substrate on which the glaze film having the same shape is not formed on the obtained glaze film, a wavelength of 808 nm is formed along the glaze film from the glass substrate side on which the glaze film is not formed. A semiconductor laser (output: 10 W, scanning speed: 5 mm / s) was irradiated. The case where the sealing material was softened and flowed by the laser beam and both the glass substrates were bonded was evaluated as “possible”, and the case where the sealing material was not softened and flowd and the both glass substrates were not bonded was evaluated as “not possible”.

  As is clear from Table 1, sample No. Since 1-3 contained the transition metal oxide powder, both glass substrates could be joined by laser light. On the other hand, sample No. Since No. 4 did not contain a transition metal oxide, the laser beam could not be properly absorbed, and both glass substrates could not be bonded by the laser beam.

Claims (16)

In a sealing material containing glass powder and refractory filler powder,
The glass powder and the refractory filler powder are contained in a total amount of 70 to 99.9% by volume,
Furthermore, 0.1-20 volume% of transition metal oxide powder is contained, The sealing material characterized by the above-mentioned.   The sealing material according to claim 1, wherein the transition metal oxide powder is CuO. Sealing material according to claim 1 or 2, transition metal oxide average particle diameter D ₅₀ of the powder is characterized in that it is 5μm or less. The sealing material according to claim 1, wherein the transition metal oxide powder has a maximum particle size D _max of 30 μm or less. The glass powder is Bi ₂ O ₃ —B ₂ O ₃ glass, Bi ₂ O ₃ —SiO ₂ glass, ZnO—B ₂ O ₃ —SiO ₂ glass, V ₂ O ₅ —P ₂ O ₅ glass, The sealing material according to claim 1, wherein the sealing material is any one of SnO—P ₂ O ₅ glass.   The sealing material according to claim 1, wherein the glass powder contains a transition metal oxide in an amount of 0.1 mol% or more as a glass composition.   The sealing material according to any one of claims 1 to 6, wherein the content of the refractory filler powder is 0.1 to 75% by volume.   The refractory filler powder is one or more selected from cordierite, willemite, alumina, zirconium tungstate phosphate, zirconium tungstate, zirconium phosphate, zircon, zirconia, and tin oxide. Item 8. The sealing material according to any one of Items 1 to 7. The sealing material according to claim 1, wherein an average particle diameter D ₅₀ of the refractory filler powder is less than 15 μm. The sealing material according to any one of claims 1 to 9, wherein the maximum particle diameter _Dmax of the refractory filler powder is 30 µm or less.   It is used for sealing by irradiation light, The sealing material in any one of Claims 1-10 characterized by the above-mentioned.   The sealing material according to claim 11, wherein the irradiation light is a laser beam.   The sealing material according to claim 11, wherein the irradiation light is infrared light. The sealing material according to claim 1, wherein the thermal expansion coefficient is 75 × 10 ⁻⁷ / ° C. or less.   The sealing material according to any one of claims 1 to 14, which does not substantially contain PbO.   The sealing material according to claim 1, which is used for sealing an organic EL device or a solar cell.