Glass composition, glass paste, sealing package, and organic electroluminescent element

Abstract

To provide a glass composition that is superior in terms of water resistance, has a smaller coefficient of thermal expansion, and has excellent fluidity during melting and width of allowable temperature range during calcination.SOLUTION: Provided is a glass composition that is characterized by containing V2O5 by 25.0 to 40.0%, TeO2 by 25.5 to 30.0%, ZnO by 15.0 to 30.0%, Nb2O5 by 5.5% to 8.0%, Al2O3 by 0 to 5.0%, BaO by 0 to 4.5%, B2O3 by 0 to 6.0%, Bi2O3 by 0 to 0.4%, and ZrO2 by 0 to 4.5% in terms of mol% based on oxides, and being substantially free of alkali metal oxides and PbO.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a glass composition, a glass paste, a sealing package, and an organic electroluminescence device.

Background Art

[0002] Flat panel display devices (FPDs) such as organic EL displays (Organic Electro-Luminescence Displays: OELDs) and plasma display panels (PDPs) have a structure in which a light-emitting element is sealed by a glass package in which a pair of glass substrates are sealed. Further, a liquid crystal display device (LCD) has a structure in which liquid crystal is sealed between a pair of glass substrates. Furthermore, solar cells such as organic thin-film solar cells and dye-sensitized solar cells have a structure in which a solar cell element (photoelectric conversion element) is sealed between a pair of glass substrates.

[0003] Among these, in the case of an organic EL display, since the light-emitting characteristics of the organic EL element are significantly deteriorated by contact with moisture, it is necessary to strictly block the organic EL element from the outside air. Further, since the organic EL element is damaged when exposed to high temperatures, the sealing method is extremely important.

[0004] Therefore, as a sealing method for an organic EL display, a method of using a glass composition as a sealing material and performing sealing by local heating is regarded as promising. Generally, the glass composition is mixed with an organic vehicle and used after being made into a paste. This paste is applied to one glass substrate by screen printing or dispensing, etc., and baked to form a pre-fired layer. Next, the other glass substrate is overlaid, and the glass composition is melted and sealed by local heating using a laser or the like on the pre-fired layer.

[0005] The glass composition used as the sealing material desirably has high water resistance, a thermal expansion coefficient close to that of the material to be sealed, and a wide allowable temperature (process margin) during melting of the glass composition in order to reduce the thermal adverse effect on the organic EL element in laser sealing.

[0006] As such, as glass compositions used as sealing materials, for example, Patent Document 1 describes a TeO2-ZnO-B2O3-based glass composition used for sealing organic EL displays. Also, Patent Document 2 discloses a V2O5-ZnO-TeO2-based glass composition. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Patent No. 6357937 [Patent Document 2] Patent No. 6022070 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] In recent years, organic EL displays have been increasing in screen size. When the screen size increases, the line width of the sealing portion needs to be increased compared to smaller screen sizes. When the line width of the sealing portion is increased, stress due to the difference in thermal expansion between the sealed material and the material to be sealed becomes more likely during laser sealing, which may cause cracks in the sealing layer and the material to be sealed. Therefore, in order to ensure the reliability of the sealed package, the sealing material is required to have a thermal expansion coefficient that is as close as possible to the thermal expansion coefficient of the material to be sealed.

[0009] Furthermore, while conventional sealed packages typically consist of glass substrates sealed together, in recent years there has been a demand for sealed packages that, for example, seal a glass substrate with a metal film deposited on its surface. Even when sealing a substrate with a metal film deposited on its surface, excellent sealing strength is required. Sealing strength can be improved by increasing the fluidity of the sealing material.

[0010] The glass compositions described in Patent Documents 1 and 2 had room for further improvement in terms of water resistance, coefficient of thermal expansion, fluidity during melting, and wide allowable temperature range during firing.

[0011] In view of the above circumstances, the present invention aims to provide a vanadium-based glass composition for use in sealing joints between glass components in flat displays such as organic EL displays and liquid crystal displays by local heating methods such as laser heating, which is superior to conventional glass compositions in terms of water resistance, a smaller coefficient of thermal expansion, fluidity during melting, and a wider allowable temperature range during firing. Furthermore, the present invention aims to provide a sealing material and glass paste containing the glass composition, as well as a sealing package and an organic electroluminescent element having a sealing layer containing the glass composition. [Means for solving the problem]

[0012] The inventors of the present invention have discovered that the above problems can be solved by a glass composition having a glass composition within a specific range, and have completed the present invention. The present invention provides a glass composition, glass paste, sealing package, and organic electroluminescent element having the following configurations. [1] Expressed in mole percent based on oxides, V2O5 at 25.0-40.0% TeO2 at 25.5-30.0% ZnO at 15.0-30.0%, Nb2O5 at 5.5-8.0% Al2O3 at 0-5.0% BaO at 0-4.5% B2O3 at 0-6.0%, Bi2O3 at 0-0.4%, and It contains 0-4.5% ZrO2, A glass composition characterized by being substantially free of alkali metal oxides and PbO. [2] The glass composition according to [1], containing 1.0 to 5.0% of B2O3 in mol% on an oxide basis. [3] The glass composition according to [1] or [2], which contains more than 6.2% of Nb2O5 in mol% on an oxide basis. [4] The glass composition according to any one of [1] to [3], wherein the total content of V2O5, TeO2 and ZnO (V2O5 + TeO2 + ZnO) is 80 to 91% in terms of mol% based on oxides. [5] The glass composition according to any one of [1] to [4], wherein the ratio of the content represented by (V2O5 / TeO2) is 1.0 to 1.6 in terms of mol% based on oxides. [6] The glass composition according to any one of [1] to [5], wherein the total content of Bi2O3, TeO2 and BaO (Bi2O3 + TeO2 + BaO) is 25.5 to 31.0% in terms of mol% based on oxides. [7] The glass composition according to any one of [1] to [6], wherein the total content of Al2O3 and ZrO2 (Al2O3 + ZrO2) is 0 to 7.0% in terms of mol% based on oxides. [8] A glass paste containing the glass composition according to any one of [1] to [7] and an organic vehicle. [9] A sealing package having a first substrate, a second substrate disposed opposite to the first substrate, and a sealing layer disposed between the first substrate and the second substrate for adhering the first substrate and the second substrate, wherein the sealing layer is a sealing package containing the glass composition according to any one of [1] to [7].

[10] A stacked structure including a substrate, an anode, an organic thin film layer, and a cathode stacked on the substrate, a glass member placed on the substrate covering the outer surface side of the stacked structure, and a sealing layer for adhering the substrate and the glass member, wherein the sealing layer is an organic electroluminescence device containing the glass composition according to any one of [1] to [7]. [Effect of the Invention]

[0013] The glass composition of the present invention is more excellent than conventional glass compositions in terms of water resistance, has a smaller thermal expansion coefficient, and is excellent in fluidity during melting and the width of the allowable temperature range during firing. [Brief Description of the Drawings]

[0014] [Figure 1] Figure 1 is a front view showing an embodiment of the sealed package. [Figure 2] Figure 2 is a cross-sectional view taken along line A-A of the sealed package shown in Figure 3. [Figure 3A] Figure 3A is a process diagram showing an embodiment of a method for manufacturing the sealed package. [Figure 3B] Figure 3B is a process diagram showing an embodiment of a method for manufacturing the sealed package. [Figure 3C] Figure 3C is a process diagram showing an embodiment of a method for manufacturing the sealed package. [Figure 3D] Figure 3D is a process diagram showing an embodiment of a method for manufacturing the sealed package. [Figure 4] Figure 4 is a plan view of the first substrate used in manufacturing the sealed package shown in Figure 1. [Figure 5] Figure 5 is a cross-sectional view taken along line B-B of the first substrate shown in Figure 4. [Figure 6] Figure 6 is a plan view of the second substrate used in manufacturing the sealed package shown in Figure 1. [Figure 7] Figure 7 is a cross-sectional view taken along line C-C of the second substrate shown in Figure 6. [Figure 8] Figure 8 is a conceptual diagram of an organic electroluminescence element which is an example of the sealed package.

Embodiments for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described. Note that the present invention is not limited to the embodiments described below. Also, in the following drawings, members and parts having the same function may be denoted by the same reference numerals and may be described, and duplicate descriptions may be omitted or simplified. Further, the embodiments shown in the drawings are schematized for clearly explaining the present invention, and do not necessarily accurately represent the actual size and scale.

[0016] <Glass Composition> The glass composition of this embodiment is characterized by containing, in molar percentages based on oxides, 25.0-40.0% V2O5, 25.5-30.0% TeO2, 15.0-30.0% ZnO, 5.5-8.0% Nb2O5, 0-5.0% Al2O3, 0-4.5% BaO, 0-6.0% B2O3, 0-0.4% Bi2O3, and 0-4.5% ZrO2, and is substantially free of alkali metal oxides and PbO.

[0017] Next, the components of the glass composition of this embodiment will be described. In the following description, unless otherwise specified, the "%" in the content of each component of the glass composition is expressed on an oxide basis, i.e., as a mole percent in terms of oxide. In this specification, the "~" that indicates a numerical range is used to include upper and lower limits.

[0018] If the glass composition used as a sealing material contains alkali metal oxides, the alkali components will diffuse into the sealed material, such as a glass substrate, when the sealing material is exposed to high temperatures during or after sealing, causing the sealed material to deteriorate. Therefore, the glass composition of this embodiment is substantially free of alkali metal oxides. In this specification, "substantially free" means that it is free of alkali metal oxides other than unavoidable impurities, i.e., not intentionally added. Therefore, the glass composition of this embodiment may contain trace amounts of alkali metal oxides as unavoidable impurities. The alkali metal oxide content in the glass composition of this embodiment is preferably 1000 ppm or less, and more preferably 500 ppm or less. In this specification, alkali metal oxides refer to Li2O, Na2O, and K2O. Furthermore, ppm refers to mass ppm.

[0019] Furthermore, in order to reduce the environmental burden, the glass composition of this embodiment is substantially lead-free, i.e., PbO-free. Note that "substantially lead-free" means that the PbO content in the glass composition is 1000 ppm or less.

[0020] V2O5 is a glass-forming oxide that forms the glass network and is essential as a low-softening component. It is also effective as a laser absorption component. On the other hand, if the V2O5 content is too high, the water resistance will decrease, and the glass stability during glass manufacturing may decrease, making the glass more prone to devitrification. Conversely, if the V2O5 content is too low, the glass transition temperature may rise, and the low-temperature sealing properties may deteriorate. Therefore, the V2O5 content should be 25.0 to 40.0%. A V2O5 content of 28.0% or more is preferred, 30.0% or more is more preferred, 32.0% or more is even more preferred, 39.0% or less is preferred, 38.0% or less is more preferred, and 37.0% or less is even more preferred.

[0021] TeO2 is a glass-forming oxide that forms a glass network and is essential as a low-softening component. It also has the function of improving the fluidity and water resistance of the glass composition. On the other hand, if the TeO2 content is too high, the coefficient of thermal expansion increases. If it is too low, the glass transition temperature may rise, potentially worsening the low-temperature sealing properties, and crystallization may occur more easily during sealing firing. Furthermore, the effects of improving fluidity and water resistance cannot be fully obtained. Therefore, the TeO2 content should be set to 25.5 to 30.0%. The TeO2 content is preferably 26.0% or more, preferably 29.0% or less, more preferably 28.0% or less, and even more preferably 27.5% or less.

[0022] ZnO is essential as a component that reduces the coefficient of thermal expansion. On the other hand, if the ZnO content is too high, the stability of the glass may decrease during glass manufacturing, making the glass more prone to devitrification. Conversely, if the content is too low, the coefficient of thermal expansion will be high. Therefore, the ZnO content is 15.0 to 30.0%. The ZnO content is preferably 17.0% or more, more preferably 18.5% or more, even more preferably 20.0% or more, preferably 28.0% or less, more preferably 26.5% or less, and even more preferably 25.0% or less.

[0023] Nb2O5 is essential as a component that reduces the coefficient of thermal expansion and improves water resistance. On the other hand, if the Nb2O5 content is too high, the glass is prone to crystallization during laser firing and sealing, and if it is too low, the coefficient of thermal expansion becomes large, and the effect of improving water resistance is not sufficiently obtained. Therefore, the Nb2O5 content should be set to 5.5 to 8.0%. Generally, when Nb2O5 content is high (for example, 5% or more), the glass tends to crystallize during laser firing and sealing, making it difficult to add large amounts of Nb2O5 in conventional methods. The inventors have found that by sufficiently increasing the proportion of amorphous components such as TeO2, it is possible to obtain a glass composition with excellent water resistance and a low coefficient of thermal expansion, even when containing 5.5% or more Nb2O5, without the glass crystallizing during firing. The Nb2O5 content is preferably more than 6.2%, and more preferably 6.5% or more. Furthermore, in order to avoid crystallization of the glass during laser firing sealing, the Nb2O5 content is 8.0% or less, preferably 7.8% or less, more preferably 7.6% or less, and even more preferably 7.4% or less.

[0024] Although Al2O3 is not essential, it is a component that has the effect of reducing the coefficient of thermal expansion and further improving water resistance, so it is preferable to include it in the glass composition of this embodiment. In this embodiment, the Al2O3 content is 0 to 5.0%. When Al2O3 is included, the Al2O3 content is preferably 0.5% or more, more preferably 1.0% or more, and even more preferably 1.5% or more. Furthermore, in order to maintain the glass transition temperature within an appropriate range and to avoid crystallization of the glass during laser firing and sealing, the Al2O3 content is 5.0% or less, preferably 4.5% or less, more preferably 4.0% or less, and even more preferably 3.5% or less.

[0025] Although BaO is not essential, it is an effective component for stabilizing glass, and therefore it is preferable to include it in the glass composition of this embodiment. In this embodiment, the BaO content is 0 to 4.5%. When BaO is included, the BaO content is preferably 0.5% or more. Furthermore, in order to maintain the glass transition temperature and thermal expansion coefficient within an appropriate range, the BaO content is 4.5% or less, preferably 3.5%, more preferably 2.5% or less, and even more preferably 2.0% or less.

[0026] Although B2O3 is not essential, it is a glass-forming oxide that forms a glass network and improves glass stability, so its inclusion in the glass composition of this embodiment is preferable. In this embodiment, the B2O3 content is 0 to 6.0%. When B2O3 is included, the B2O3 content is preferably 1.0% or more, more preferably 1.5% or more, and even more preferably 2.0% or more. However, if the B2O3 content is too high, the glass becomes unstable and more prone to crystallization during laser firing and sealing. Therefore, to avoid crystallization of the glass due to excessive B2O3 content, the B2O3 content is 6.0% or less, preferably 5.0% or less, more preferably 4.5% or less, and even more preferably 4.0% or less.

[0027] Bi2O3 readily reacts with the glass substrate during sealing and improves adhesive strength by forming a reaction layer; therefore, it is preferable to include it in the glass composition of this embodiment. However, if the Bi2O3 content is too high, the glass may crystallize more easily during laser firing sealing, and the coefficient of thermal expansion may increase. Furthermore, excessive reaction with the glass substrate may incorporate high-melting-point components such as SiO2 from the glass substrate into the glass composition, raising the bonding point and potentially increasing the residual stress of the sealing material after sealing. Therefore, the Bi2O3 content is 0 to 0.4%. Here, the Bi2O3 content is preferably 0.3% or less, more preferably 0.2% or less, even more preferably 0.15% or less, and particularly preferably 0.1% or less. The lower limit of the Bi2O3 content is 0%, meaning that the glass composition of this embodiment may substantially not contain Bi2O3.

[0028] Although ZrO2 is not essential, its inclusion is preferable because it improves chemical stability. In this embodiment, the ZrO2 content is 0 to 4.5%. When ZrO2 is included, the ZrO2 content is preferably 0.5% or more, and more preferably 1.0% or more. Furthermore, in order to maintain the glass transition temperature within an appropriate range and to avoid crystallization of the glass during laser firing and sealing, the ZrO2 content is 4.5% or less, preferably 3.5% or less, more preferably 3.0% or less, and even more preferably 2.5% or less.

[0029] A total content of V2O5, TeO2, and ZnO (V2O5 + TeO2 + ZnO) of 80-91% is preferable because it makes it easier to achieve both water resistance and glass stabilization. For the same reason, (V2O5 + TeO2 + ZnO) of 82% or more is more preferable, 84% or more is even more preferable, 89% or less is more preferable, and 88% or less is even more preferable.

[0030] A ratio of V2O5 to TeO2 content (V2O5 / TeO2) of 1.0 to 1.6 is preferable because it suppresses crystallization during sealing and firing, thus stabilizing the glass. For the same reason, a ratio of 1.1 or higher is more preferable, and a ratio of 1.5 or lower is even more preferable.

[0031] A total content of Bi2O3, TeO2, and BaO (Bi2O3 + TeO2 + BaO) of 25.5 to 31.0% is preferable because it allows the coefficient of thermal expansion to be within an appropriate range. For the same reason, a (Bi2O3 + TeO2 + BaO) content of 26.0% or more is more preferable, and 30.0% or less is even more preferable.

[0032] A total content of Al2O3 and ZrO2 (Al2O3 + ZrO2) of 0 to 7.0% is preferable because it suppresses crystallization of the glass during laser firing and sealing while improving water resistance. For the same reason, (Al2O3 + ZrO2) is more preferably 1.5% or more, even more preferably 2.5% or more, even more preferably 6.0% or less, and even more preferably 5.0% or less.

[0033] While CuO is not essential, it may be included because it has the effect of reducing the coefficient of thermal expansion and improving water resistance. Furthermore, it is also effective as a laser absorption component. Therefore, by including CuO, the amount of pigment added for laser absorption purposes during glass paste production can be reduced, and instead, a larger amount of low-expansion filler can be included, making it possible to produce a glass paste with a lower coefficient of thermal expansion. On the other hand, if the CuO content is high, crystallization is more likely to occur during laser sealing and firing. Therefore, the CuO content is preferably 1.0 to 10.0%. Here, in order to obtain sufficient laser absorption effect, the CuO content is preferably 1.0% or more, more preferably 2.0% or more, and even more preferably 3.0% or more. Also, in order to avoid crystallization of the glass, the CuO content is preferably 10.0% or less, more preferably 8.0% or less, and even more preferably 7.0% or less.

[0034] While Fe2O3 is not essential, it may be included as it is also effective as a laser absorption component. Including Fe2O3 allows for a reduction in the amount of pigment added for laser absorption during glass paste preparation, enabling the inclusion of a higher amount of low-expansion filler, thus producing a glass paste with a lower thermal expansion coefficient. On the other hand, a high Fe2O3 content can lead to glass crystallization during laser firing and sealing, raising the glass's softening point and worsening low-temperature sealing properties. Therefore, the Fe2O3 content is preferably 1.0-7.0%. Here, a Fe2O3 content of 7.0% or less is preferable, 5.0% or less is more preferable, and 2.0% or less is even more preferable. Furthermore, to obtain the laser absorption effect, a Fe2O3 content of 1.0% or more is preferable. However, if CuO is present, the above effects can be obtained even without Fe2O3.

[0035] While MnO2 is not essential, it may be included because it is an effective laser absorption component. Including MnO2 allows for a reduction in the amount of pigment added for laser absorption during glass paste preparation, enabling the inclusion of a higher amount of low-expansion filler, thus producing a glass paste with a lower thermal expansion coefficient. On the other hand, a high MnO2 content can lead to crystallization of the glass during laser firing. Therefore, a MnO2 content of 1.0-7.0% is preferable. Here, a MnO2 content of 7.0% or less is preferable, 5.0% or less is more preferable, and 2.0% or less is even more preferable. Furthermore, to obtain the laser absorption effect, a MnO2 content of 1.0% or more is preferable. However, if CuO or Fe2O3 is present, the above effects can be obtained even without MnO2.

[0036] The glass composition of this embodiment may contain components other than those listed above (hereinafter referred to as "other components") to the extent that they do not impair the purpose of the present invention. The total content of other components is preferably 10.0% or less.

[0037] The glass composition of this embodiment may also contain other components such as SiO2, MgO, CaO, SrO, P2O5, TiO2, CeO2, La2O3, CoO, MoO3, Sb2O3, WO3, GeO2, and Ta2O5. However, if too much P2O5 is included, the water resistance may decrease. Therefore, although P2O5 may be included, the content is preferably 5% or less, and even more preferably substantially absent. In this context, "substantially absent" means that the P2O5 content in the glass composition is 1000 ppm or less.

[0038] (Thermal properties of glass compositions) The glass composition of this embodiment preferably has a glass transition temperature (Tg) of 340°C or lower, as this results in good low-temperature sealing properties. More preferably, Tg is 330°C or lower, and even more preferably 320°C or lower. The lower limit of Tg is not particularly limited, but for example, it is 280°C or higher.

[0039] In this embodiment, the glass composition is preferably such that the fourth inflection point Ts when heated using a thermal analysis device (DTA) is 400°C or lower, as this results in good low-temperature sealing properties. Ts is more preferably 390°C or lower, and even more preferably 380°C or lower. The lower limit of Ts is not particularly limited, but for example, it is 350°C or higher.

[0040] In this embodiment, the glass composition preferably has a crystallization onset temperature Tcs of 470°C or higher when heated using a thermal analysis device (DTA), as this results in good low-temperature sealing properties. More preferably, Tcs is 480°C or higher, and even more preferably 490°C or higher. There is no particular upper limit to Tcs.

[0041] In this embodiment, the glass composition preferably has a crystallization temperature Tcp of 450°C or higher when heated using a thermal analysis device (DTA) because this results in good low-temperature sealing properties. More preferably, Tcp is 470°C or higher, and even more preferably 480°C or higher. There is no particular upper limit to Tcp.

[0042] In this embodiment, the glass composition preferably has a temperature difference (Tcs-Ts) greater than 100°C between the crystallization start temperature and the fourth inflection point. A Tcs-Ts greater than 100°C allows for a wider process margin during glass melting, reducing the thermal impact on the organic EL element during laser firing and sealing. A Tcs-Ts of 110°C or higher is more preferable, and 120°C or higher is even more preferable. There is no particular upper limit to Tcs-Ts.

[0043] The glass transition temperature Tg, the fourth inflection point Ts, the crystallization start temperature Tcs, and the crystallization temperature Tcp are determined using differential thermal analysis (DTA) by taking the first inflection point as Tg, the fourth inflection point as Ts, the start point of the exothermic peak as Tcs, and the exothermic peak temperature as Tcp from a DTA chart measured using a DTA instrument.

[0044] (Method for manufacturing glass composition) The method for manufacturing the glass composition of this embodiment is not particularly limited. For example, it can be manufactured by the method shown below.

[0045] First, a raw material mixture is prepared. The raw materials are not particularly limited as long as they are those used in the manufacture of ordinary oxide-based glass, and oxides, carbonates, etc., can be used. The type and proportion of raw materials are adjusted as appropriate to create a raw material mixture so that the composition of the resulting glass composition falls within the above range.

[0046] Next, the raw material mixture is heated by a known method to obtain a molten product. The heating and melting temperature (melting temperature) is preferably 950 to 1200°C, more preferably 1000°C or higher, and even more preferably 1150°C or lower. The heating and melting time is preferably 30 to 90 minutes.

[0047] Subsequently, the molten material is cooled and solidified to obtain the glass composition of this embodiment. The cooling method is not particularly limited. A roll-out machine or press machine may be used, or rapid cooling by dropping into a cooling liquid may be used. The resulting glass composition is preferably completely amorphous, i.e., has a crystallinity of 0%. However, it may contain crystalline portions as long as it does not impair the effects of the present invention.

[0048] The glass composition of this embodiment obtained in this way may be in any form. For example, it may be in the form of a block, a plate, a thin plate (flake), a powder, etc.

[0049] When using the glass composition of this embodiment as a sealing material, the glass composition is preferably in the form of glass powder. Furthermore, when evaluating the above properties of the glass composition, glass powder is also preferred from the viewpoint of observing its performance as a sealing material.

[0050] (Glass powder) When the glass composition of this embodiment is in the form of glass powder, the particle size of the glass powder can be appropriately selected depending on the application. In the case of sealing materials, which is a typical application of glass powder, the particle size of the glass powder is preferably 0.1 to 100 μm.

[0051] Furthermore, if the particle size of the glass powder is large, it is prone to sedimentation and separation when it is pasteurized and applied or dried, and there is also the problem of an increased thickness of the resulting sealing layer. Therefore, when using glass powder in paste form, the particle size of the glass powder is preferably in the range of 0.1 to 5.0 μm, and more preferably 0.1 to 2.5 μm.

[0052] In this specification, "particle size" refers to the 50% particle size (D) based on volume in the cumulative particle size distribution. 50 This means, specifically, the particle size at which the cumulative amount accounts for 50% of the volume in the cumulative particle size curve of the particle size distribution measured using a laser diffraction / scattering particle size distribution analyzer.

[0053] The glass powder made from the glass composition of this embodiment can be obtained, for example, by grinding the glass composition. Therefore, the particle size of the glass powder can be adjusted by the grinding conditions. Examples of grinding methods include rotary ball mills, vibrating ball mills, planetary mills, jet mills, attritors, media stirring mills (bead mills), jaw crushers, and roll crushers.

[0054] In particular, when processing glass powder to a fine particle size of 5.0 μm or less, wet grinding is recommended. Wet grinding involves grinding the material in a solvent such as water or alcohol using media made of alumina or zirconia, or a bead mill.

[0055] To adjust the particle size of the glass powder, in addition to grinding the glass composition, classification may be performed using a sieve or the like, if necessary.

[0056] Furthermore, when using the glass powder made from the glass composition of this embodiment as a sealing material, the glass powder may be used in its original form, or, depending on the sealing method, it may be used as a sealing material mixed with a low-expansion filler and / or a laser-absorbing material. In addition, from the viewpoint of improving workability, it is preferable to use the glass composition and the sealing material in paste form.

[0057] <Glass paste> The glass paste of this embodiment contains the glass composition of this embodiment described above and an organic vehicle. The glass paste may also contain a low-expansion filler and / or a laser-absorbing substance depending on the sealing method. The organic vehicle, low-expansion filler, and laser-absorbing substance will be described below.

[0058] As an organic vehicle, for example, a solution of a resin, which is a binder component, in a solvent can be used. Specifically, resins such as methylcellulose, ethylcellulose, carboxymethylcellulose, oxyethylcellulose, benzylcellulose, propylcellulose, and nitrocellulose can be dissolved in solvents such as terpineol, texanol, butyl carbitol acetate, and ethyl carbitol acetate, and these can be used as organic vehicles. Furthermore, acrylic resins such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and 2-hydroxyethyl (meth)acrylate can be dissolved in solvents such as methyl ethyl ketone, terpineol, texanol, butyl carbitol acetate, and ethyl carbitol acetate and used as organic vehicles. In this specification, (meth)acrylate means at least one of acrylate and methacrylate. Furthermore, polyalkylene carbonates such as polyethylene carbonate and polypropylene carbonate can be dissolved in solvents such as triethyl acetyl citrate, propylene glycol diacetate, diethyl succinate, ethyl carbitol acetate, triacetin, texanol, dimethyl adipate, ethyl benzoate, and a mixture of propylene glycol monophenyl ether and triethylene glycol dimethyl ether, and these can be used as organic vehicles.

[0059] The ratio of resin to solvent in the organic vehicle is not particularly limited, but it is selected so that the viscosity of the organic vehicle can adjust the viscosity of the glass paste. Specifically, the mass ratio of resin to solvent in the organic vehicle is preferably about 3:97 to 30:70.

[0060] Low-expansion fillers have a lower coefficient of thermal expansion than glass compositions, approximately -15 × 10⁻⁶. -7 ~45×10 -7 It has a thermal expansion coefficient of approximately / °C. Low-expansion fillers are added to reduce the thermal expansion coefficient of the sealing layer.

[0061] The low-expansion filler is not particularly limited, but at least one selected from silica, alumina, zirconia, zirconium silicate, cordierite, zirconium phosphate compounds, soda-lime glass, and borosilicate glass is preferred. Examples of zirconium phosphate compounds include (ZrO)2P2O7, NaZr2(PO4)3, KZr2(PO4)3, and Ca 0.5 Examples include Zr2(PO4)3, NbZr(PO4)3, Zr2(WO3)(PO4)2, and complex compounds thereof.

[0062] The particle size of the low-expansion filler is preferably 0.1 to 5.0 μm, and more preferably 0.1 to 2.0 μm.

[0063] The content of the low-expansion filler is set so that the thermal expansion coefficient of the sealing layer approaches that of the material to be sealed (e.g., a glass substrate). The content of the low-expansion filler is preferably 1 volume% or more, more preferably 5 volume% or more, and even more preferably 10 volume% or more, relative to the total volume of the mixture of the glass composition, the low-expansion filler, and the laser-absorbing material (hereinafter sometimes referred to as the mixed material). On the other hand, if the content of the low-expansion filler is too high, the fluidity of the sealing material when it melts will be poor, so the content of the low-expansion filler is preferably 50 volume% or less, more preferably 45 volume% or less, and even more preferably 40 volume% or less, relative to the volume of the mixed material.

[0064] While not particularly limited, examples of laser-absorbing materials include, in addition to the Cu, Fe, and Mn that constitute CuO, Fe2O3, and MnO2 mentioned above, at least one metal selected from Cr, Ni, Co, etc., or compounds such as oxides containing such metals (inorganic pigments). Furthermore, the laser-absorbing material may also be a pigment other than those mentioned above.

[0065] The particle size of the laser-absorbing material is preferably 0.1 to 5.0 μm, and more preferably 0.1 to 2.0 μm.

[0066] If the content of laser-absorbing material is too low, it may become difficult to sufficiently melt the sealing material by laser irradiation. Therefore, the total content of laser-absorbing material, including other laser-absorbing materials, is preferably 0.1 volume% or more, more preferably 1 volume% or more, and even more preferably 3 volume% or more, relative to the volume of the mixed material. On the other hand, if the content of laser-absorbing material is too high, the fluidity of the sealing material during melting will be poor, thereby reducing the adhesive strength. Therefore, the content of laser-absorbing material is preferably 20 volume% or less, more preferably 18 volume% or less, and even more preferably 15 volume% or less, relative to the volume of the mixed material.

[0067] The ratio of the mixed material to the organic vehicle in the glass paste is adjusted as appropriate according to the desired viscosity of the glass paste. Specifically, a mass ratio of mixed material to organic vehicle of approximately 60:40 to 90:10 is preferred. In addition to the mixed material and organic vehicle, known additives may be added to the glass paste as needed, and only to the extent that they do not contradict the objectives of the present invention.

[0068] The glass paste is prepared by known methods using rotary mixers equipped with stirring blades, roll mills, ball mills, etc.

[0069] <Sealed packaging> Next, we will describe the sealing package to which the glass composition of this embodiment is applied. Figures 1 and 2 are a plan view and a cross-sectional view showing one embodiment of the sealed package. Figures 3A to 3D are process diagrams showing one embodiment of the manufacturing method of the sealed package shown in Figure 3. Figures 4 and 5 are a plan view and a cross-sectional view of the first substrate used in the manufacturing of the sealed package shown in Figures 1 and 2. Figures 6 and 7 are a plan view and a cross-sectional view of the second substrate used in the manufacturing of the sealed package shown in Figures 1 and 2.

[0070] The sealed package 10 constitutes a lighting device (such as OEL lighting) using an FPD such as an OELD, PDP, or LCD, or an organic electroluminescent (OEL) element, or a solar cell such as a dye-sensitized solar cell. In other words, the sealed package 10 includes a first substrate 11, a second substrate 12 positioned opposite the first substrate, and a sealing layer 15 positioned between the first substrate and the second substrate to bond them together. The sealing layer 15 also contains the glass composition of this embodiment described above.

[0071] The first substrate 11 is, for example, an element substrate on which electronic element portions 13 are mainly provided. The second substrate 12 is, for example, a sealing substrate mainly used for sealing. Electronic element portions 13 are provided on the first substrate 11. The first substrate 11 and the second substrate 12 are arranged facing each other and are bonded together by a sealing layer 15 arranged in a frame shape between them.

[0072] Examples of the first substrate 11 and the second substrate 12 include glass substrates and substrates on which a metal film is deposited on the surface. As glass substrates, soda-lime glass substrates and alkali-free glass substrates are used. Examples of soda-lime glass substrates include AS and PD200 (both manufactured by AGC, product names), and chemically strengthened versions thereof. Examples of alkali-free glass substrates include AN100 (manufactured by AGC, product name), EAGLE2000 (manufactured by Corning, product name), EAGLE GX (manufactured by Corning, product name), JADE (manufactured by Corning, product name), #1737 (manufactured by Corning, product name), OA-10 (manufactured by Nippon Electric Glass Co., Ltd., product name), and Tempax (manufactured by Schott, product name). Examples of substrates on which a metal film is deposited include substrates on which a film containing Ti is deposited on the surface of a glass substrate. The material of the substrate is not particularly limited and may be any known material. When the metal film is a multilayer film, it is preferable that the outermost layer contains Ti. The first substrate 11 and the second substrate 12 may be the same substrate, or they may be a combination of different substrates.

[0073] The electronic element section 13 includes, for example, an OEL element in the case of an OELD or OEL lighting, a plasma light-emitting element in the case of a PDP, a liquid crystal display element in the case of an LCD, and a dye-sensitized solar cell element (dye-sensitized photoelectric conversion element) in the case of a solar cell. The electronic element section 13 can be configured with various known structures and is not limited to the structure shown in the figure.

[0074] In the sealed package 10 shown in Figures 1 and 2, the electronic element section 13, such as an OEL element or a plasma light-emitting element, is provided on the first substrate 11. If the electronic element section 13 is a dye-sensitized solar cell element or the like, element films such as wiring films or electrode films are provided on the opposing surfaces of the first substrate 11 and the second substrate 12, although these are not shown.

[0075] When the electronic element section 13 is an OEL element or the like, a gap remains between the first substrate 11 and the second substrate 12. This gap may be left as is, or it may be filled with a transparent resin or the like. The transparent resin may be bonded to the first substrate 11 and the second substrate 12, or it may simply be in contact with them.

[0076] If the electronic element 13 is a dye-sensitized solar cell element or the like, the electronic element 13 is arranged across the entire area between the first substrate 11 and the second substrate 12, although this is not shown in the diagram. Note that the object to be sealed is not limited to the electronic element 13, but may also be a photoelectric converter or the like. Furthermore, the sealing package 10 may be a building material such as double-glazed glass that does not have an electronic element 13.

[0077] Below, as an example of a sealed package, the organic electroluminescent element constituting the OELD will be described in detail with reference to Figure 8. The organic electroluminescent element 210 obtained using the glass composition of this embodiment comprises a substrate 211, a laminated structure 213 having an anode 213a, an organic thin film layer 213b, and a cathode 213c laminated on the substrate 211, a glass member 212 covering the outer surface of the laminated structure 213 and placed on the substrate 211, and a sealing layer 215 adhering the substrate 211 and the glass member 212. The sealing layer 215 also contains the glass composition of this embodiment described above.

[0078] (Method of manufacturing sealed packages) Next, an embodiment of a method for manufacturing a sealed package to which the glass composition of this embodiment described above is applied will be explained. The aforementioned glass paste is used for sealing. The glass paste is applied to the second substrate 12 in a frame-like manner, and then dried to form a coating layer. Application methods include screen printing, gravure printing, and dispensing. Drying is performed to remove the solvent and is usually carried out at a temperature of 120°C or higher for 10 minutes or more. If solvent remains in the coating layer, the binder components may not be sufficiently removed during subsequent calcination.

[0079] The coated layer is subjected to calcination to form a calcined layer 15a (Figures 6 and 7). Calcination is performed by heating the coated layer to a temperature below the glass transition temperature of the glass composition contained in the sealing material to remove the binder component, and then heating it to a temperature above the softening point of the glass composition contained in the sealing material.

[0080] The first substrate 11 is provided with an electronic component section 13 according to the specifications of the sealed package 10 (Figures 4 and 5).

[0081] Next, the second substrate 12, which has a pre-fired layer 15a, and the first substrate 11, which has an electronic element section 13, are stacked so that the pre-fired layer 15a faces each other (Figures 3A and 3B).

[0082] Subsequently, the calcined layer 15a is irradiated with laser light 16 through the second substrate 12 to perform calcination (Figure 3C). The laser light 16 is irradiated while scanning along the frame-shaped calcined layer 15a. By irradiating the entire circumference of the calcined layer 15a with laser light 16, a frame-shaped sealing layer 15 is formed between the first substrate 11 and the second substrate 12. Alternatively, the laser light 16 may be irradiated onto the calcined layer 15a through the first substrate 11.

[0083] The type of laser beam 16 is not particularly limited, and laser beams such as semiconductor lasers, carbon dioxide lasers, excimer lasers, YAG lasers, and HeNe lasers can be used. The irradiation conditions of the laser beam 16 are selected according to the thickness, line width, and cross-sectional area in the thickness direction of the calcined layer 15a. The output of the laser beam 16 is preferably 2 to 150 W. If the output of the laser beam is less than 2 W, the calcined layer 15a may not melt. If the output of the laser beam exceeds 150 W, cracks and the like are more likely to occur in the first substrate 11 and the second substrate 12. The output of the laser beam 16 is more preferably 5 to 120 W.

[0084] In this way, a sealed package 10 is manufactured in which the electronic element portion 13 is hermetically sealed between the first substrate 11 and the second substrate 12 by a sealing layer 15 (Figure 3D).

[0085] The above describes a method of firing by irradiation with laser light 16, but the firing method is not necessarily limited to the method performed by irradiation with laser light 16. Other firing methods can be adopted depending on the heat resistance of the electronic component 13, the configuration of the sealing package 10, etc. For example, if the electronic component 13 has high heat resistance, or if there is no electronic component 13, instead of irradiating with laser light 16, the entire assembly shown in Figure 3B may be placed in a firing furnace such as an electric furnace, and the entire assembly including the pre-fired layer 15a may be heated to form the sealing layer 15.

[0086] Although embodiments of the sealing package of the present invention have been described above with reference to one example, the sealing package of the present invention is not limited to these. The configuration can be appropriately modified as necessary, as long as it does not contradict the spirit of the present invention. [Examples]

[0087] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Examples 1 to 15 are examples. Examples 16 to 37 are comparative examples.

[0088] [Examples 1-37] (Manufacturing of glass compositions) The raw materials were prepared and mixed to achieve the composition shown in molar percentages in the glass composition column of Tables 1 and 2, and then melted in a platinum crucible in an electric furnace at 1000-1100°C for 1 hour. The resulting molten liquid was formed into a sheet using a water-cooled roller, and then dry-milled using a ball mill. The resulting material was then passed through a sieve with a mesh size of 100 to obtain the glass composition. D of this glass composition 50 When measured using a Microtrac particle size distribution analyzer (manufactured by Nikkiso Co., Ltd.), all samples were found to be within the range of 2 to 5 μm.

[0089] Next, the following measurements and evaluations were performed on these glass compositions. In Tables 1 and 2, a "-" in the evaluation column indicates that the sample was not evaluated because no crystallization peak was observed or vitrification did not occur due to DTA.

[0090] (DTA test) A differential thermal analysis (DTA) instrument, TG-DTA8122, manufactured by Rigaku Corporation, was used to perform thermal analysis on the glass composition at a heating rate of 10°C / min. From the resulting DTA chart, the glass transition temperature Tg, the fourth inflection point Ts [°C], the crystallization onset temperature Tcs [°C], and the crystallization temperature Tcp [°C] were determined. The glass transition temperature Tg, fourth inflection point Ts, crystallization onset temperature Tcs, and crystallization temperature Tcp were determined by defining the first inflection point of the DTA chart as Tg, the fourth inflection point as Ts, the start of the exothermic peak as Tcs, and the exothermic peak temperature as Tcp. In addition, as an evaluation of the allowable temperature during firing, the temperature difference (Tcs-Ts) between the crystallization onset temperature and the fourth inflection point was determined, and the results are shown in the table below. A value of (Tcs-Ts) greater than 100°C was considered acceptable.

[0091] (Thermal expansion coefficient (α)) Each glass composition was molded into a rectangular parallelepiped to obtain a fired body for thermal expansion measurement. The obtained fired body for thermal expansion measurement was processed into a cylindrical shape with a diameter of 5 ± 0.5 mm and a length of 2 ± 0.05 cm. The processed fired body for thermal expansion measurement was heated in a RIGAKU ThermoplusEVO2 system TDL8411 at a heating rate of 10°C / min, and the thermal expansion coefficient α (unit: 10) at 50 to 250°C was measured.-7 The thermal expansion coefficient (°C) was calculated. The results are shown in the table below. Items with a thermal expansion coefficient α of less than 91 were considered acceptable.

[0092] (Liquidity assessment) A sample (flow button) with a diameter of 15 mm was prepared by press-molding 4 g of glass composition. The obtained flow button was placed on a glass substrate and fired at 450-460°C for 30 minutes, according to the softening point of each glass composition, to obtain a fired body for fluidity evaluation. Next, the diameter of the obtained fired body for fluidity evaluation was measured at four points by dividing the angle into four equal parts, and the average value of these four diameters was calculated as the FB diameter (unit: mm). Fluidity, gloss, and adhesion were evaluated for each sample according to the following criteria. The results obtained are shown in the table below. Samples with a circle (○) in the fluidity and gloss evaluation were considered to pass. <Liquidity> ○: The FB diameter is 24 mm or larger. ×: The FB diameter is less than 24 mm. <Glossy> ○: The entire surface of the fired body used for fluidity evaluation was glossy. △: A portion of the surface of the fired body used for fluidity evaluation lacked gloss. ×: The entire surface of the fired body used for fluidity evaluation lacked gloss.

[0093] (Water resistance evaluation) Glass flakes from each glass composition were left to stand for 48 hours at a temperature of 121°C and a humidity of 100% RH. The fired specimens after standing were then evaluated for water resistance according to the following criteria. The results are shown in the table below. A circle (〇) was considered a pass. <Criteria for evaluating water resistance> ○: No discoloration was observed on the entire surface of the fired specimen used for water resistance evaluation. △: Discoloration was observed on a portion of the surface of the fired specimen used for water resistance evaluation. ×: The entire surface of the fired specimen used for water resistance evaluation was discolored.

[0094] [Table 1]

[0095] [Table 2]

[0096] The glass compositions of Examples 1 to 15, which are examples, exhibited excellent water resistance, a low coefficient of thermal expansion, and excellent fluidity during melting and a wide allowable temperature range during firing.

[0097] On the other hand, in comparative example 16, the Bi2O3 content was greater than 0.4% and the TeO2 content was less than 25.5%, resulting in a narrower allowable temperature range during firing and inferior fluidity. Furthermore, comparative examples 17-19 had a high coefficient of thermal expansion and inferior water resistance because the Nb2O5 content was less than 5.5%. Furthermore, in comparative example 20, the Bi2O3 content was greater than 0.4%, resulting in a large coefficient of thermal expansion. Furthermore, in the comparative example, Example 21, the Nb2O5 content exceeded 8.0%, resulting in a narrower permissible temperature range during firing, as well as inferior fluidity and water resistance. Furthermore, in comparative example 22, the V2O5 content exceeded 40.0% and the Nb2O5 content was less than 5.5%, resulting in inferior fluidity and water resistance. Furthermore, in the comparative example, Example 23, the TeO2 content was over 30.0%, resulting in a large coefficient of thermal expansion and inferior water resistance. Furthermore, comparative examples 24 and 25 had inferior water resistance because they contained less than 25.5% TeO2 and more than 30.0% ZnO. In example 25, the permissible temperature range during firing was narrow, and the fluidity was also poor. Furthermore, comparative examples 26 and 27 had inferior water resistance because their ZrO2 content exceeded 4.5%. Furthermore, in the comparative example, Example 28, the Bi2O3 content was greater than 0.4%, resulting in a large coefficient of thermal expansion. Furthermore, in comparative example 29, since V2O5 was over 40.0%, ZnO was less than 15.0%, and BaO was over 4.5%, the allowable temperature range during firing was narrow, the coefficient of thermal expansion was large, and the fluidity was poor. Furthermore, in the comparative example, Example 30, the V2O5 content was less than 25.5% and the ZnO content was greater than 30.0%, so vitrification did not occur. Furthermore, in the comparative example, Example 31, the water resistance evaluation was inferior because the ZnO content exceeded 30.0%. Furthermore, in the comparative example, Example 32, the Al2O3 content exceeded 5.0%, resulting in a narrower allowable temperature range during firing and inferior fluidity. Furthermore, in the comparative example, Example 33, the V2O5 content exceeded 40.0%, resulting in a narrower allowable temperature range during firing, a larger coefficient of thermal expansion, and inferior fluidity and water resistance. Furthermore, in comparative examples 34-36, since the Bi2O3 content was greater than 0.4%, example 34 had a narrow allowable temperature range during firing, example 35 had poor water resistance, and example 36 had a large coefficient of thermal expansion and even worse water resistance. Furthermore, in the comparative example, Example 37, the B2O3 content exceeded 6.0%, resulting in inferior water resistance. [Explanation of Symbols]

[0098] 10: Sealed package 11: First circuit board 12: Second circuit board 13: Electronic elements section 15: Sealing layer 15a: Calcined layer 16: Laser light 210: Organic electroluminescent element 211: Circuit board 212: Glass components 213: Laminated Structure 213a:Anode 213b: Organic thin film layer 213c: Cathode 215: Sealing layer

Claims

1. Expressed in mole percent based on oxides, V ２ O ５ 25.0-40.0% TeO ２ 25.5-30.0% 15.0 to 30.0% ZnO, Nb ２ O ５ 5.5-8.0%, Al ２ O ３ を0~5.0%、 BaO at 0-4.5% B ２ O ３ from 0 to 6.0%, Bi ２ O ３ to 0-0.4%, and ZrO ２ It contains 0-4.5% of A glass composition characterized by being substantially free of alkali metal oxides and PbO.

2. In mole percent based on oxides, B ２ O ３ The glass composition according to claim 1, comprising 1.0 to 5.0% of the above.

3. In mole percent based on oxides, Nb ２ O ５ The glass composition according to claim 1 or 2, which contains more than 6.2% of the following.

4. In mole percent based on oxides, V ２ O ５ and TeO ２ and the total amount of ZnO (V ２ O ５ +TeO ２ The glass composition according to claim 1 or 2, wherein the content of (+ZnO) is 80 to 91%.

5. In mole percent based on oxides, (V ２ O ５ / TeO ２ The glass composition according to claim 1 or 2, wherein the ratio of the content represented by ) is 1.0 to 1.

6.

6. In mole percent based on oxides, Bi ２ O ３ and TeO ２ and the total BaO content (Bi ２ O ３ +TeO ２ The glass composition according to claim 1 or 2, wherein the amount of (BaO) is 25.5 to 31.0%.

7. In mole percent based on oxides, Al ２ O ３ and ZrO ２ Total content (Al ２ O ３ +ZrO ２ The glass composition according to claim 1 or 2, wherein the content of ) is 0 to 7.0%.

8. A glass paste containing the glass composition according to claim 1 or 2 and an organic vehicle.

9. A sealing package comprising: a first substrate; a second substrate disposed opposite to the first substrate; and a sealing layer disposed between the first substrate and the second substrate to bond the first substrate and the second substrate, The sealing layer comprises a sealing package containing the glass composition described in claim 1 or 2.

10. The device comprises a substrate, a laminated structure having an anode, an organic thin film layer, and a cathode laminated on the substrate, a glass member covering the outer surface of the laminated structure and placed on the substrate, and a sealing layer adhering the substrate and the glass member. The sealing layer comprises an organic electroluminescent element containing the glass composition described in claim 1 or 2.

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