Sealed package and organic electroluminescence element

Abstract

To provide a seal-and-bonding package superior in impact-resistant strength.SOLUTION: A seal-and-bonding package 10 comprises: a first substrate 11 which is an element substrate on which an electronic device part 13 is mainly provided; a second substrate 12 which is opposed to the first substrate 11 and is a sealing substrate mainly used for sealing; and a seal-and-bonding layer 15 disposed between the first substrate 11 and the second substrate 12 and serving to bonding the first substrate 11 and the second substrate 12. The seal-and-bonding layer 15 comprises a glass composition. The glass transition point of glass making the glass composition is 350°C or below. A reaction layer resulting from the reaction of at least one of the first substrate 11 and the second substrate 12, and the seal-and-bonding layer 15 is 4-25 nm in total thickness.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a sealed package and an organic electroluminescent element. [Background technology]

[0002] Organic Electro-Luminescence (OLED) display Flat panel display devices (FPDs) such as organic light emitting diode (OLED) displays and plasma display panels (PDPs) have a structure in which a light emitting element is sealed in a glass package formed by sealing a pair of glass substrates. Liquid crystal display devices (LCDs) have 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, organic EL displays require strict isolation of organic electroluminescence elements (organic EL elements) from the outside air, as the light-emitting properties of these elements deteriorate significantly when exposed to moisture. Furthermore, organic EL elements are damaged when exposed to high temperatures, so the sealing method is extremely important.

[0004] Therefore, a promising sealing method for organic EL displays is to use glass powder as a sealing material and seal by localized heating. Glass powder is obtained by crushing glass and is generally used as a paste by mixing it with an organic vehicle. This paste is applied to one glass substrate by screen printing or dispensing, and then baked to form a pre-baked layer. Next, the other glass substrate is placed on top of the other, and the pre-baked layer is locally heated using a laser or other method to melt the glass powder and seal the substrate.

[0005] As such, as an example of glass used as a sealing material, Patent Document 1 describes a TeO2-ZnO-B2O3-based glass used to seal organic EL displays. Patent Document 2 also discloses an electronic device that includes a pair of glass substrates and a sealing layer, in which a reaction layer with the sealing layer is generated inside the glass substrate, the maximum depth of which is 30 nm or more from the interface with the sealing layer. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6357937 [Patent Document 2] Patent No. 5692218 Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, organic electroluminescence elements have also been used in display panels for smartphones, wearable devices, etc. As demand for smartphones and wearable devices increases, there is a demand for high strength to withstand strong impacts, such as when these devices are dropped.

[0008] According to the inventors' investigations, it is presumed that the impact resistance is largely determined by the thermal stress accumulated in the sealing layer and the adhesive strength between the substrate and the sealing layer. The thermal stress is mainly accumulated in the sealing layer during the process in which the heated sealing material cools from near the glass transition point to room temperature during sealing. Therefore, if the glass transition point can be lowered to suppress the thermal stress, sealing can be performed at a lower temperature, and the impact resistance will be improved. In addition, the adhesive strength between the substrate and the sealing layer is also important for achieving high impact resistance.

[0009] In contrast, the glass described in Patent Document 1 has a high glass transition point of approximately 350° C. or higher. The glass frit described in Patent Document 2 has a softening point of 420° C., so it is expected that the glass transition point will also be high. Therefore, there is room for improvement in sealing properties at low temperatures.

[0010] The present invention has been made in view of the above, and has an object to provide a sealed package and an organic electroluminescence element that are excellent in impact resistance. [Means for solving the problem]

[0011] The present inventors have discovered that by using glass having a glass transition point of 350°C or less as a sealing layer and by setting the thickness of the reaction layer between the substrate and the sealing layer within an appropriate range, it is possible to achieve sealing properties at low temperatures and high adhesive strength between the substrate and the sealing layer, and have completed the present invention.

[0012] That is, the present invention provides a sealed package and an organic electroluminescent element having the following configurations. [1] A sealed 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 and bonding the first substrate to the second substrate, the sealing layer is made of a glass composition, the glass composition has a glass transition temperature of 350°C or less; a reaction layer is formed by reaction between at least one of the first substrate and the second substrate and the sealing layer, The thickness of the reaction layer is 4 to 25 nm. [2] The sealed package according to [1], wherein the glass contains V2O5 as a main component. [3] The sealed package according to [2], wherein the glass further contains Bi2O3. [4] The sealed package according to any one of [1] to [3], wherein the glass composition further contains at least one of a low expansion filler and a laser absorbing substance. [5] The sealed package according to any one of [1] to [4] above, wherein at least one of the first substrate and the second substrate is a glass substrate. [6] A semiconductor device 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 and bonding the first substrate to the second substrate; the sealing layer is made of a glass composition, the glass composition has a glass transition temperature of 350°C or less; a reaction layer is formed by reaction between at least one of the first substrate and the second substrate and the sealing layer, An organic electroluminescence element, wherein at least one of the reaction layers has a thickness of 4 to 25 nm. [7] The organic electroluminescence element according to [6], wherein the glass contains V2O5 as a main component. [8] The organic electroluminescence device according to [7], wherein the glass further contains Bi2O3. [9] The organic electroluminescence device according to any one of [6] to [8] above, wherein the glass composition further contains at least one of a low expansion filler and a laser absorbing substance.

[10] The organic electroluminescence device according to any one of [6] to [9] above, wherein at least one of the first substrate and the second substrate is a glass substrate. [Effects of the Invention]

[0013] The sealed package and organic electroluminescence element according to the present invention have excellent impact resistance against dropping and the like. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a front view showing one embodiment of a sealed package. [Figure 2] FIG. 2 is a cross-sectional view of the sealed package shown in FIG. 1 taken along line AA. [Figure 3A] FIG. 3A is a process diagram showing one embodiment of a method for manufacturing a sealed package. [Figure 3B] FIG. 3B is a process diagram showing one embodiment of a method for manufacturing a sealed package. [Figure 3C] FIG. 3C is a process diagram showing one embodiment of a method for manufacturing a sealed package. [Figure 3D] FIG. 3D is a process diagram showing one embodiment of a method for manufacturing a sealed package. [Figure 4] FIG. 4 is a plan view of a first substrate used in manufacturing the sealed package shown in FIG. [Figure 5] FIG. 5 is a cross-sectional view of the first substrate taken along line BB shown in FIG. [Figure 6] FIG. 6 is a plan view of a second substrate used in manufacturing the sealed package shown in FIG. [Figure 7] FIG. 7 is a cross-sectional view of the second substrate shown in FIG. 6 taken along line CC. [Figure 8] FIG. 8 is a conceptual diagram of a pre-fired layer obtained by pre-firing a glass powder mixture. [Figure 9] FIG. 9 is a conceptual diagram of a sealing layer obtained by heating a glass powder mixture by laser irradiation or the like. [Figure 10] FIG. 10 is a conceptual diagram of an organic electroluminescence element, which is an example of a sealed package. [Figure 11] FIG. 11 is a plan view of a glass substrate used in manufacturing the sealed package of the embodiment. [Figure 12] FIG. 12 is a cross-sectional view of the glass substrate shown in FIG. 11 taken along line DD. [Figure 13] FIG. 13 is a cross-sectional view showing a sealed package according to an embodiment. [Figure 14] FIG. 14 is a plan view of a sealed package having a support substrate provided on one side. [Figure 15] 15 is a cross-sectional view taken along the line FF of the sealed package provided with the support substrate shown in FIG. [Figure 16] FIG. 16 is a diagram showing a method for measuring the falling ball strength. [Figure 17] FIG. 17 is a graph showing the relationship between the falling ball strength and the thickness of the reaction layer. [Figure 18] FIG. 18 is a schematic plan view of a glass substrate used for measuring the thickness of a reaction layer. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the embodiments described below. Furthermore, in the following drawings, components and parts that perform the same function may be described using the same reference numerals, and duplicated descriptions may be omitted or simplified. Furthermore, the embodiments shown in the drawings are schematic in order to clearly explain the present invention, and do not necessarily accurately represent the actual size or scale.

[0016] <Sealed package> The sealed package according to this embodiment includes a first substrate and a second substrate disposed opposite the first substrate, and a sealing layer between the first and second substrates to bond the substrates together. The sealing layer is made of a glass composition, and the glass transition point of the glass constituting the glass composition is 350°C or lower. A reaction layer formed by reaction between at least one of the first substrate and the second substrate and the sealing layer has a thickness of 4 to 25 nm. In this specification, the term "glass composition" refers to an inorganic mixture containing glass. The glass composition may further contain at least one of a low-expansion filler and a laser-absorbing material in addition to glass, or may consist of glass alone.

[0017] Figures 1 and 2 are a plan view and a cross-sectional view showing one embodiment of a sealed package. Figures 3A to 3D are process diagrams showing one embodiment of a method for manufacturing the sealed package shown in Figure 1. Figures 4 and 5 are a plan view and a cross-sectional view of a first substrate used in manufacturing the sealed package shown in Figures 1 and 2. Figures 6 and 7 are a plan view and a cross-sectional view of a second substrate used in manufacturing the sealed package shown in Figures 1 and 2.

[0018] The sealed package 10 constitutes an FPD such as an OELD, PDP, or LCD, a lighting device (OEL lighting, etc.) using a light emitting element such as an organic electroluminescence (OEL) element, or a solar cell such as a dye-sensitized solar cell. That is, the sealed package 10 has a first substrate 11, a second substrate 12 disposed opposite the first substrate, and a sealing layer 15 disposed between the first substrate 11 and the second substrate 12 to bond the first substrate to the second substrate. The sealing layer 15 is made of a glass composition, and the glass transition point of the glass constituting the glass composition is 350°C or lower.

[0019] The first substrate 11 is, for example, an element substrate on which an electronic element section 13 is mainly provided. The second substrate 12 is, for example, a sealing substrate mainly used for sealing. The first substrate 11 is provided with the electronic element section 13. The first substrate 11 and the second substrate 12 are arranged to face each other and are bonded therebetween by a sealing layer 15 arranged in a frame shape.

[0020] A reaction layer (not shown) formed by reaction between the substrate and the sealing layer is formed between at least one of the first substrate 11 and the second substrate 12 and the sealing layer 15. The reaction layer has a thickness of 4 to 25 nm. The sealing layer and the reaction layer will be described later.

[0021] The first substrate 11 and the second substrate 12 are not particularly limited as long as at least one of them is a substrate capable of forming a reaction layer with the sealing layer, but a glass substrate is preferred because it has excellent laser transparency and can efficiently heat the sealing layer. As the glass substrate, a soda lime glass substrate, an alkali-free glass substrate, or the like is more preferably used. Examples of soda lime glass substrates include AS and PD200 (both trade names manufactured by AGC Corporation) and chemically strengthened versions of these. Examples of alkali-free glass substrates include AN100 (manufactured by AGC, product name), EAGEL2000 (manufactured by Corning Incorporated, product name), EAGEL GX (manufactured by Corning Incorporated, product name), JADE (manufactured by Corning Incorporated, product name), #1737 (manufactured by Corning Incorporated, product name), OA-10 (manufactured by Nippon Electric Glass Co., Ltd., product name), and Tempax (manufactured by Schott Corporation, product name). The first substrate 11 and the second substrate 12 may be the same or different.

[0022] The electronic element unit 13 has, 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, or a dye-sensitized solar cell element, i.e., a dye-sensitized photoelectric conversion element, in the case of a solar cell. The electronic element unit 13 can have any of various known structures and is not limited to the structure shown in the figure.

[0023] 1 and 2, an OEL element, a plasma light-emitting element, or the like is provided on the first substrate 11 as the electronic element section 13. When the electronic element section 13 is a dye-sensitized solar cell element, or the like, element films such as wiring films and electrode films (not shown) are provided on the opposing surfaces of the first substrate 11 and the second substrate 12.

[0024] When the electronic element section 13 is an OEL element or the like, a space remains between the first substrate 11 and the second substrate 12. This space may be left as is, or 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 may simply be in contact with them.

[0025] When the electronic element unit 13 is a dye-sensitized solar cell element or the like, the electronic element unit 13 is disposed over the entire space between the first substrate 11 and the second substrate 12, although this is not shown. The object to be sealed is not limited to the electronic element unit 13, but may be a photoelectric conversion device or the like. The sealed package 10 may also be a building material such as double-glazed glass that does not have the electronic element unit 13.

[0026] [Sealing layer] The sealing layer in this embodiment is made of a glass composition, and the glass transition point of the glass that constitutes the glass composition is 350° C. or less. Hereinafter, this glass may be referred to as “low-melting glass”.

[0027] The glass composition containing the low-melting-point glass allows the formation of a sealing layer at a low temperature, thereby suppressing the thermal stress that accumulates when the heated sealing material cools from near the glass transition point to room temperature during sealing, thereby improving the impact resistance of the resulting sealed package.

[0028] The glass transition point (Tg) of the low-melting glass may be 350°C or lower, and from the viewpoint of obtaining better low-temperature sealing properties, Tg is preferably 340°C or lower, more preferably 330°C or lower. There is no particular limitation on the lower limit of the glass transition point, but 290°C or higher is preferred. By setting the glass transition point to 290°C or higher, when a glass paste is prepared by mixing an organic vehicle containing a resin with the glass composition, it is possible to prevent the glass from softening before the resin is removed, thereby preventing the resin from remaining in the sealing layer. The glass transition point (Tg) of the low-melting glass was measured using a differential thermal analyzer, and the first inflection point was taken as the glass transition point.

[0029] The low-melting glass may be made of one or more types of glass. When the low-melting glass is made of one type of glass, the glass transition point of the glass is required to be within the above range. Even when two or more types of glass are used as materials for constituting the low-melting glass, the glass transition temperature (Tg) of the obtained low-melting glass can be measured using a differential thermal analyzer and estimated from the first inflection point, and it is sufficient that the glass transition temperature is within the above range.

[0030] When two or more types of glass are used as materials for constituting the low-melting glass, the total content of the glass materials having a glass transition point of 350°C or less relative to the total amount of the glass materials for constituting the low-melting glass cannot be uniquely determined depending on the glass transition point of each glass, but is preferably 80% by volume or more, more preferably 85% by volume or more. There is no particular upper limit on the total content, and all of the glass materials may have a glass transition point of 350°C or less, i.e., 100% by volume.

[0031] The composition of the low-melting glass is not particularly limited as long as it has the above-mentioned properties, but it is preferable that the low-melting glass contains V2O5 as a main component. V2O5 is a glass-forming oxide that forms a glass network and is a component that lowers the glass transition temperature. It is also effective as a laser absorption component. In this specification, the term "main component" refers to the component that is contained in the largest amount, expressed in mole percent based on oxide, among the components that constitute the glass. When two or more types of glass are used as materials for constituting the low-melting glass, the composition of the low-melting glass is determined from the composition of each glass, expressed in mole percent based on oxide, and the content ratio (volume %) of each glass. Specifically, the V2O5 content is preferably 10% or more, more preferably 20% or more, even more preferably 25% or more, and even more preferably 30% or more. Furthermore, from the viewpoint of preventing a decrease in water resistance and a decrease in glass stability during glass production that makes the glass more susceptible to devitrification, the V2O5 content is preferably 50% or less, more preferably 45% or less, even more preferably 40% or less, and even more preferably 35% or less.

[0032] The low-melting glass preferably further contains Bi2O3. When a glass substrate is used as the substrate, Bi2O3 easily reacts with the glass substrate during the formation of the sealing layer, forming a reaction layer. This reaction layer improves adhesive strength and provides the sealed package with better impact resistance. Specifically, the Bi2O3 content is preferably 0.5% or more, more preferably 1.0% or more, even more preferably 1.5% or more, and even more preferably 2.0% or more. Furthermore, from the viewpoint of maintaining good low-temperature sealing properties, the Bi2O3 content is preferably 20.0% or less, more preferably 15.0% or less, even more preferably 10.0% or less, and even more preferably 7.0% or less.

[0033] (low melting point glass) An embodiment of the composition of the low-melting-point glass contained in the glass composition that forms the sealing layer is described below. The composition is not limited to the one described below, and is not particularly limited as long as the glass transition point is within the above range and a reaction layer of appropriate thickness can be formed with the substrate. Furthermore, when two or more types of glass are used as materials that form the low-melting-point glass, the composition of each glass, expressed in mole percent based on the oxides, and the composition determined from their content (volume %) (hereinafter referred to as the "average composition") may be as follows:

[0034] The low-melting glass in this embodiment preferably contains substantially no alkali metal oxides and contains, in mole percent on an oxide basis, 10.0 to 50.0% V2O5, 14.5 to 45.0% TeO2, 5.0 to 45.0% ZnO, and 0.5 to 20.0% Bi2O3. In the following explanation of each component, unless otherwise specified, the "%" in the content of each component of the low-melting glass is expressed on an oxide basis, that is, in mole % converted into oxide.

[0035] If the low-melting-point glass contains alkali metal oxides, the alkali components may diffuse into the substrate or other materials to be sealed, possibly causing deterioration of the materials, when the sealing material is exposed to high temperatures during or after sealing. Therefore, it is preferable that the low-melting-point glass be substantially free of alkali metal oxides. Note that "substantially free" means that the glass contains no alkali metal oxides other than unavoidable impurities, i.e., the glass is not intentionally added. Therefore, the low-melting glass may contain a small amount of alkali metal oxide as an unavoidable impurity. The content of alkali metal oxide in the low-melting glass 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, and the content of alkali metal oxides refers to the total content of these. Furthermore, ppm refers to ppm by mass.

[0036] V2O5 is a glass-forming oxide that forms a glass network and acts as a low-softening component, i.e., a component that lowers the glass transition point, and is therefore preferably contained. It is also effective as a laser-absorbing component. Thus, since lowering the glass transition point results in excellent low-temperature sealing properties and high impact resistance, it is preferable to contain V2O5 as the main component. The V2O5 content is preferably 10.0% or more, more preferably 15.0% or more, even more preferably 20.0% or more, and even more preferably 25.0% or more. From the viewpoint of preventing a decrease in water resistance and a decrease in glass stability during glass production, which causes the glass to be more susceptible to devitrification, the V2O5 content is preferably 50.0% or less, more preferably 45.0% or less, even more preferably 40.0% or less, and even more preferably 35.0% or less.

[0037] TeO2 is a glass oxide that forms a glass network and is a low-softening component, so it is preferably contained. From the viewpoints of improving low-temperature sealing properties by lowering the glass transition point and preventing crystallization during firing and sealing, the TeO2 content is preferably 14.5% or more, more preferably 16.0% or more, even more preferably 18.0% or more, and even more preferably 20.0% or more. Furthermore, from the viewpoint of preventing the thermal expansion coefficient from becoming too large, the TeO2 content is preferably 45.0% or less, more preferably 40.0% or less, even more preferably 35.0% or less, and even more preferably 30.0% or less.

[0038] ZnO is preferably contained as a component that reduces the thermal expansion coefficient. The ZnO content is preferably 5.0% or more, more preferably 10.0% or more, even more preferably 15.0% or more, and even more preferably 20.0% or more. On the other hand, from the viewpoint of preventing a decrease in glass stability during glass production and devitrification of the glass, the ZnO content is preferably 45.0% or less, more preferably 40.0% or less, even more preferably 35.0% or less, and even more preferably 30.0% or less.

[0039] Bi2O3 is a component that readily reacts with substrates during sealing and improves adhesive strength by forming a reaction layer. Therefore, Bi2O3 is important for the low-melting-point glass of this embodiment, and it is preferable to include Bi2O3 together with V2O5. By setting the Bi2O3 content at a certain level or higher, the adhesive strength can be sufficiently improved. On the other hand, by setting the Bi2O3 content at a certain level or lower, the glass transition temperature does not become too high, and good low-temperature sealing properties can be maintained. Furthermore, when the substrate is a glass substrate, excessive reaction with the glass substrate can be suppressed, preventing high-melting-point components in the glass substrate, such as SiO2, from being incorporated into the glass composition. As a result, the bonding point does not increase, and the residual stress in the sealing layer after sealing is prevented from increasing.

[0040] When V2O5-TeO2-ZnO-based glass is used as the low-melting glass, the Bi2O3 content, which can improve adhesive strength while maintaining low-temperature sealing properties, is preferably 0.5 to 20.0%. The Bi2O3 content is more preferably 1.0% or more, even more preferably 1.5% or more, even more preferably 2.0% or more, and is more preferably 15.0% or less, even more preferably 10.0% or less, and even more preferably 7.0% or less.

[0041] In a low-melting glass containing V2O5 as a main component and further containing Bi2O3, the ratio of the V2O5 content to the TeO2 content, expressed as V2O5 / TeO2, is preferably 0.5 or more, more preferably 1.0 or more, from the viewpoint of suppressing crystallization during firing and sealing and stabilizing the glass, and is preferably 2.5 or less, more preferably 2.0 or less.

[0042] CuO is a component that has the effect of lowering the thermal expansion coefficient and improving water resistance, so its inclusion is preferable. It is also effective as a laser-absorbing component. By including CuO, the amount of pigment added for the purpose of laser absorption during the preparation of the glass paste for forming the sealing layer can be reduced, and instead, a large amount of low-expansion filler can be added. This allows for a glass paste with a lower thermal expansion coefficient to be obtained. From the above viewpoints, the CuO content is preferably 1.0% or more, more preferably 2.0% or more, and even more preferably 5.0% or more. On the other hand, from the viewpoint of preventing crystallization of the glass during firing and sealing, the CuO content is preferably 10.0% or less, more preferably 8.0% or less, and even more preferably 7.5% or less.

[0043] Since Fe2O3 is also effective as a laser absorption component, it may be included. By including Fe2O3, it is possible to reduce the amount of pigment added for the purpose of laser absorption during glass paste preparation and instead include a large amount of low-expansion filler. This allows for a glass paste with a lower thermal expansion coefficient to be obtained. From the above perspective, the Fe2O3 content is preferably 1.0% or more. However, as long as CuO or MnO is included, the above effects can be achieved even without Fe2O3. On the other hand, from the perspective of preventing crystallization of the glass during firing and sealing and further suppressing a decrease in low-temperature sealing properties due to an increase in the glass transition point, the Fe2O3 content is preferably 7.0% or less, more preferably 5.0% or less, and even more preferably 2.0% or less.

[0044] MnO may be included because it is an effective laser absorbing component. By including MnO, the amount of pigment added for the purpose of laser absorption during glass paste preparation can be reduced, allowing for the inclusion of a large amount of low-expansion filler instead. This allows for a glass paste with a lower thermal expansion coefficient. From the above perspective, the MnO content is preferably 1.0% or more. However, as long as CuO or Fe2O3 is included, the above effects can be achieved even without MnO. On the other hand, from the perspective of preventing crystallization of the glass during firing and sealing, the MnO content is preferably 7.0% or less, more preferably 5.0% or less, and even more preferably 2.0% or less.

[0045] From the viewpoint of obtaining a favorable laser absorption effect, the total content of CuO, Fe2O3, and MnO expressed as (CuO + Fe2O3 + MnO) is preferably 1.0% or more, more preferably 2.0% or more, even more preferably 4.0% or more, and even more preferably 5.0% or more. Furthermore, from the viewpoint of avoiding crystallization of the glass during laser firing and sealing, this total content is preferably 10.0% or less, more preferably 8.0% or less, and even more preferably 7.5% or less.

[0046] CuO, Fe2O3, and MnO are all effective laser-absorbing components. Among these components, it is preferable to include a large amount of CuO in order to balance the effect of low-temperature sealing due to laser absorption and the prevention of glass crystallization. Specifically, the ratio of the CuO content to the total content of CuO, Fe2O3, and MnO, expressed as {CuO / (CuO + Fe2O3 + MnO)}, is preferably 30% or more (0.3 or more), more preferably 50% or more (0.5 or more), and even more preferably 70% or more (0.7 or more). Alternatively, the ratio may be 100%, meaning that only CuO is contained.

[0047] B2O3 is a glass oxide and is a component that forms a glass network and improves glass stability, so it is preferably contained. When B2O3 is contained, its content is preferably 0.5% or more, more preferably 1.0% or more, and even more preferably 1.5% or more. On the other hand, from the viewpoint of avoiding excessive inclusion that makes the glass unstable and prone to crystallization during firing and sealing, the B2O3 content is preferably 10.0% or less, more preferably 7.5% or less, and even more preferably 5.0% or less.

[0048] BaO is an effective component for stabilizing glass, so it may be contained. When contained, the BaO content is preferably 2.0% or more. On the other hand, in order to maintain the glass transition temperature and thermal expansion coefficient within appropriate ranges, the BaO content is preferably 10.0% or less, and more preferably 8.0% or less.

[0049] Al2O3 and Nb2O5 have the effect of lowering the thermal expansion coefficient and improving water resistance, so they may each be contained. When contained, the content of Al2O3 and Nb2O5 is preferably 2.0% or more. On the other hand, in order to maintain the glass transition temperature in an appropriate range, the content of Al2O3 and Nb2O5 is preferably 10.0% or less, and more preferably 8.0% or less, respectively.

[0050] Preferably, the total content of V2O5, TeO2, and ZnO, represented by (V2O5 + TeO2 + ZnO), is 78.0 to 89.0%, and the total content of Al2O3 and Nb2O5, represented by (Al2O3 + Nb2O5), is 5.0 to 11.0%. Within these ranges, it is easy to achieve both water resistance and glass stabilization. For the same reasons, (V2O5 + TeO2 + ZnO) is more preferably 79.0% or more and 88.0% or less. Additionally, (Al2O3 + Nb2O5) is more preferably 6.0% or more and 10.0% or less.

[0051] The low-melting glass may contain components other than the above components (hereinafter referred to as "other components") within the range that does not impair the object of the present invention. The total content of other components is preferably 10.0% or less.

[0052] Other components include CaO, TiO2, ZrO2, CeO2, La2O3, CoO, MoO3, Sb2O3, WO3, GeO2, etc.

[0053] Furthermore, from the viewpoint of reducing the burden on the environment, it is preferable that the low-melting glass contains substantially no lead, ie, no PbO.

[0054] (Method of manufacturing sealing layer) The sealing layer is made of a glass composition, and the glass constituting the glass composition is a low-melting glass. The method for producing the sealing layer is not particularly limited, but it can be produced, for example, by the method shown below.

[0055] First, a raw material mixture is prepared. The raw materials are not particularly limited as long as they are raw materials used in the production of ordinary oxide-based glasses, and oxides, carbonates, etc. can be used. The raw material mixture is prepared by appropriately adjusting the types and proportions of the raw materials so that the composition of the resulting glass falls within the above-mentioned range.

[0056] When the low-melting-point glass material is two or more types of glass with different compositions, the composition of each of the different glasses is not particularly limited, and appropriate types and proportions of raw materials, combinations of glasses, etc. may be selected so that the average composition falls within the above-mentioned range.

[0057] The raw material mixture is heated by a known method to obtain a melt. The temperature for heating and melting (melting temperature) is preferably 1000 to 1200° C., more preferably 1050° C. or higher, and more preferably 1150° C. or lower. The heating and melting time is preferably 30 to 90 minutes.

[0058] The molten material is then cooled and solidified to obtain a glass that will be used as a material for low-melting glass. The cooling method is not particularly limited, but examples of methods that can be used include using a roll-out machine or a press machine, and rapid cooling by dropping the material into a cooling liquid. The resulting glass is preferably completely amorphous, i.e., has a crystallinity of 0%, although it may contain crystallized portions as long as the effects of the present invention are not impaired.

[0059] The glass material obtained above may be in any form. Examples include block, plate, thin plate (flake), powder, etc. Among these, powder is preferred because it is easily melted when used to form a sealing layer, and when the low-melting glass material has two or more different compositions, it is easy to mix them. Furthermore, powder makes it easier to investigate the performance as a sealing material.

[0060] The particle size of the glass powder can be appropriately selected depending on the application, but the particle size of the glass powder is usually about 0.1 to 100 μm. In order to prevent settling and separation when the glass powder is made into a paste and applied or dried to form a sealing layer, and to prevent the resulting sealing layer from becoming too thick, the particle size of the glass powder is preferably 5.0 μm or less, and more preferably 2.5 μm or less. In this specification, the particle size of the powder is the 50% particle size (D 50 Specifically, it means the particle size at which the cumulative amount accounts for 50% by volume on the cumulative particle size curve of the particle size distribution measured using a laser diffraction / scattering particle size distribution analyzer.

[0061] The glass powder can be obtained by, for example, pulverizing the glass obtained above. In this case, the particle size of the powder can be adjusted by the pulverization conditions. In addition to pulverizing the glass, classification using a sieve or the like may be performed as necessary. Examples of the pulverization method include a rotary ball mill, a vibrating ball mill, a planetary mill, a jet mill, an attritor, a media stirring mill (bead mill), a jaw crusher, and a roll crusher.

[0062] In particular, when obtaining fine particles of 5.0 μm or less, it is preferable to use wet milling, which is a method of milling in a solvent such as water or alcohol using a bead mill or media made of alumina or zirconia.

[0063] Next, the glass powder is fired between the first and second substrates to form a sealing layer made of a glass composition composed of low-melting-point glass. When there are two or more types of glass that are the low-melting-point glass material, the powders of these glasses are mixed together to form a glass powder mixture, which is then fired. Pre-firing may be performed before firing.

[0064] The glass powder mixture may be, for example, a V2O5-TeO2-ZnO-based glass as the base component, to which Bi2O3-ZnO-B2O3-based glass is added, thereby obtaining the low-melting glass of this embodiment when a sealing layer is formed. Note that the base component means that the content of the base component relative to the total volume of the glass powder mixture is 50% by volume or more, preferably 70% by volume or more, and preferably 99.9% by volume or less.

[0065] The glass powder may be used as is, but from the viewpoint of improving workability, it is preferable to use it as a paste, i.e., a glass paste. When there are two or more types of glass materials that become low-melting point glass, multiple glass powders may be mixed to form a glass powder mixture and then pasteified, or multiple pastes containing glass powders with different compositions may be prepared and then mixed. The glass paste contains an organic vehicle, but both the solvent and resin are removed during the process of forming the sealing layer. Therefore, no components of the organic vehicle remain in the sealing layer. The glass paste is prepared by a known method using a rotary mixer equipped with stirring blades, a roll mill, a bead mill, or the like.

[0066] The glass composition of the sealing layer preferably contains at least one of a low expansion filler and a laser absorbing substance in addition to glass powder, depending on the sealing method.

[0067] The following describes the case where two or more types of glass are used to form low-melting glass, i.e., the pre-firing and firing of the glass powder mixture. Note that the case where V2O5-TeO2-ZnO-based glass is the base component and Bi2O3-ZnO-B2O3-based glass is the additive component is described here, but the present invention is not limited to this.

[0068] Pre-firing is preferably performed at a temperature about 10 to 50°C higher than the softening point of the V2O5-TeO2-ZnO-based glass, which is the base component. Pre-firing at such a temperature results in a pre-fired layer 100a in which Bi2O3-ZnO-B2O3-based glass 102 is scattered in softened V2O5-TeO2-ZnO-based glass 101, as shown in Fig. 8.

[0069] Next, when the pre-fired layer 100a is heated by laser irradiation or the like to be fired, it is preferable to heat the pre-fired layer 100a to a temperature at which the Bi2O3-ZnO-B2O3-based glass, which is the added component, is sufficiently melted. When fired at such a temperature, the entire layer including the Bi2O3-ZnO-B2O3-based glass 102 is melted, and it is thought that a sealing layer 100 is obtained in which the V2O5-TeO2-ZnO-based glass 101, which is the base component, and the Bi2O3-ZnO-B2O3-based glass 102, which is the added component, are mixed, as shown in Figure 9.

[0070] The sealing layer 100 has a low residual stress after being cooled to room temperature due to the low glass transition temperature of the V2O5-TeO2-ZnO-based glass, which is the base component. Furthermore, the high reactivity of Bi2O3 contained in the additive component results in excellent adhesive strength. Therefore, the sealing layer 100 has excellent impact resistance. In FIG. 9, the V2O5-TeO2-ZnO-based glass 101 portion and the Bi2O3-ZnO-B2O3-based glass 102 portion are clearly separated, but FIG. 9 is a schematic diagram, and the boundary between these portions in the sealing layer 100 is not necessarily clear.

[0071] When the pre-baked layer 100a is heated by laser irradiation or the like to melt the Bi2O3-ZnO-B2O3-based glass 102, these glasses are mixed near the interface between the Bi2O3-ZnO-B2O3-based glass 102 and the V2O5-TeO2-ZnO-based glass 101. Therefore, in the resulting sealing layer, the V2O5-TeO2-ZnO-based glass 101 portion may contain Bi2O3-ZnO-B2O3-based glass, and the Bi2O3-ZnO-B2O3-based glass 102 portion may contain V2O5-TeO2-ZnO-based glass. The above is not limited to the case where the glass powder mixture is pre-baked and fired as powder, but also applies to the case where the glass powder mixture is pre-baked and fired as a glass paste.

[0072] The low-expansion filler has a thermal expansion coefficient lower than that of the low-melting-point glass and is added to reduce the thermal expansion coefficient of the sealing layer. -7 ~45×10 -7 / ℃.

[0073] The low-expansion filler is not particularly limited, but is preferably at least one selected from the group consisting of silica, alumina, zirconia, zirconium silicate, cordierite, zirconium phosphate compounds, soda-lime glass, and borosilicate glass. Examples of zirconium phosphate compounds include (ZrO)2P2O7, NaZr2(PO4)3, KZr2(PO4)3, Ca 0.5 Examples include Zr2(PO4)3, NbZr(PO4)3, Zr2(WO3)(PO4)2, and complex compounds thereof.

[0074] The particle size of the low expansion filler is preferably 0.1 to 5.0 μm, more preferably 0.1 to 2.0 μm.

[0075] The content of the low-expansion filler is set so that the thermal expansion coefficient of the sealing layer approaches that of the substrate to be sealed. The content of the low-expansion filler is preferably 1% by volume or more, more preferably 5% by volume or more, and even more preferably 10% by volume or more, based on the total of the glass powder, low-expansion filler, and laser-absorbing substance. On the other hand, from the viewpoint of ensuring good fluidity when the sealing material is melted, the content of the low-expansion filler is preferably 50% by volume or less, more preferably 45% by volume or less, and even more preferably 40% by volume or less.

[0076] The laser absorbing substance is added for the purpose of absorbing the laser irradiated during sealing, thereby sufficiently melting the sealing material and improving low-temperature sealing properties. The laser absorbing substance is not particularly limited, but examples include Cu, Fe, and Mn that constitute the CuO, Fe2O3, and MnO described above in the glass composition, as well as at least one metal selected from Cr, Ni, Ti, Co, Zn, etc., or a compound such as an oxide containing such a metal, i.e., an inorganic pigment, etc. Furthermore, the laser absorbing substance may also be a pigment other than these.

[0077] The particle size of the laser absorbing substance is preferably 0.1 to 5.0 μm, and more preferably 0.1 to 2.0 μm.

[0078] The total content of the laser absorbing substances, including other laser absorbing substances other than CuO, Fe2O3, and MnO, is preferably 0.1% by volume or more, more preferably 1% by volume or more, and even more preferably 3% by volume or more, based on the total of the glass powder, low-expansion filler, and laser absorbing substance, from the viewpoint of optimally obtaining the effects of the laser absorbing substance. On the other hand, from the viewpoint of ensuring good fluidity when the sealing material is melted and obtaining excellent adhesive strength, the content of the laser absorbing substance is preferably 20% by volume or less, more preferably 18% by volume or less, and even more preferably 15% by volume or less.

[0079] As the organic vehicle, for example, a solvent in which a resin, which is a binder component, is dissolved, is used. Examples of resins that are binder components include methyl cellulose, ethyl cellulose, carboxymethyl cellulose, oxyethyl cellulose, benzyl cellulose, propyl cellulose, nitrocellulose, etc. In this case, examples of solvents that can be used include terpineol, texanol, butyl carbitol acetate, ethyl carbitol acetate, etc.

[0080] The resin binder component may be an acrylic resin containing an acrylic monomer such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, or 2-hydroxyethyl (meth)acrylate. In this case, the solvent may be, for example, methyl ethyl ketone, terpineol, texanol, butyl carbitol acetate, or ethyl carbitol acetate. In this specification, the term "(meth)acrylate" refers to at least one of acrylate and methacrylate.

[0081] Polyalkylene carbonates such as polyethylene carbonate and polypropylene carbonate can also be used as the resin binder component. In this case, examples of solvents that can be used include 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.

[0082] The ratio of the resin to the solvent in the organic vehicle is not particularly limited, but the viscosity of the glass paste can be adjusted to fall within a suitable range by adjusting the viscosity of the organic vehicle. The ratio of resin to solvent in the organic vehicle is preferably resin:solvent=approximately 3:97 to 30:70 (mass ratio).

[0083] The ratio of the total of the glass powder, low-expansion filler, and laser absorbing substance to the organic vehicle in the glass paste is appropriately adjusted depending on the desired viscosity of the glass paste. Specifically, the ratio of the total to the organic vehicle is preferably about 65:35 to 90:10 (mass ratio).

[0084] In addition to the above, other known additives may be added to the glass paste or glass composition as needed, provided that the addition does not interfere with the object of the present invention.

[0085] (reaction layer) The reaction layer is a layer formed by a reaction between the substrate and the sealing layer. Therefore, it is a mixed layer containing multiple elements, including the constituent elements of the substrate and the constituent elements of the sealing layer. The formation of this reaction layer between the substrate and the sealing layer strengthens the adhesion between the substrate and the sealing layer. To obtain the above effects, the thickness of the reaction layer is set to 4 nm or more. The thicker the reaction layer, the higher the adhesive strength and the impact resistance strength. Therefore, the thickness of the reaction layer is preferably 5 nm or more, more preferably 7 nm or more, and even more preferably 10 nm or more.

[0086] The reactive layer may be formed between at least one of the first substrate and the second substrate and the sealing layer, but it is preferable to form it between both the first substrate and the second substrate and the sealing layer, as this will result in higher adhesive strength as a sealed package. When a reactive layer is formed between both substrates, the thickness of either one of the reactive layers may be 4 to 25 nm, and it is more preferable that the thickness of both reactive layers is 4 to 25 nm.

[0087] On the other hand, the thickness of the reaction layer is set to 25 nm or less for the following three reasons. The thickness of the reaction layer varies depending on the temperature at which the sealing layer is formed. To thicken the reaction layer, the sealing temperature must be increased. For example, if the sealing is performed by laser irradiation, the laser output must be increased. However, if the laser output is too high, the wiring and other components located below the sealing layer will be damaged. Therefore, excessive laser output cannot be applied. Therefore, there is an upper limit to the thickness of the reaction layer.

[0088] In addition to the above, if the reaction layer becomes too thick, it will react with the layer located on the opposite side of the substrate from the sealing layer, such as the passivation film or electrodes in the case of a thin-film transistor (TFT), causing excessive bubbles to form, which reduces the strength of the material itself and also reduces impact resistance, so there is an upper limit to the thickness of the reaction layer.

[0089] Furthermore, the thickness of the reaction layer also varies depending on the composition of the glass that makes up the glass composition. For example, in the case of glass containing V2O5 as its main component, the thickness of the reaction layer can be adjusted by changing the Bi2O3 content. Specifically, increasing the Bi2O3 content makes the reaction layer thicker, but if the Bi2O3 content is too high, vitrification becomes difficult or, even if vitrification occurs, it quickly crystallizes. As this narrows the process margin during sealing, it is not practical to thicken the reaction layer by increasing the Bi2O3 content.

[0090] For the above reasons, the thickness of the reaction layer is 25 nm or less, preferably 20 nm or less, and more preferably 16 nm or less.

[0091] The generation of the reaction layer can be confirmed practically by the following method.

[0092] First, a portion of the sealed package is cut out to make it easier to polish, and used as a sample. One of the substrates is polished away from this sample. Note that if the adhesive strength is low and peeling occurs within the sealing layer, the substrate polishing step can be omitted. Next, the sample from which one substrate has been removed is immersed in an etching solution to remove the sealing layer. An acid solution capable of dissolving the constituent elements of the sealing layer is used as the etching solution. For example, if bismuth-based glass is used as the sealing layer, a 30% nitric acid solution or the like is used. Since the reaction layer is a mixed layer of the constituent elements of the substrate and the constituent elements of the sealing layer, the reaction layer is removed at the same time as the sealing layer is removed.

[0093] In this way, a substrate is obtained on which traces of the reaction layer remain as recesses, thereby confirming that a reaction layer has been formed. The surface shape of a substrate having such recesses can be confirmed using a non-contact surface roughness meter, such as a white light interferometer. The specific thickness of the reaction layer is the depth of the recesses, which are traces of the reaction layer, measured using a white light interferometer using the method described in the Examples below.

[0094] <Method of manufacturing sealed package> An example of a method for manufacturing a sealed package according to the present embodiment will be described below, but the sealed package according to the present invention is not limited to this. Furthermore, the configuration of the package can be appropriately changed as needed, provided that it does not deviate from the spirit of the present invention.

[0095] The glass paste obtained above is applied to a second substrate in a frame shape and then dried to form a coating layer. Examples of the application method include printing methods such as screen printing and gravure printing, and dispensing methods. Drying is carried out to remove the solvent contained in the glass paste, and is usually carried out for 10 minutes or more at a temperature of 120°C or higher. If the solvent remains in the coating layer, there is a risk that the resin, which is the binder component added as an organic vehicle, will not be sufficiently removed during the subsequent pre-baking.

[0096] The coating layer is pre-baked to become a pre-baked layer 15a (FIGS. 6 and 7). The pre-baking is performed by heating the coating layer to a temperature equal to or lower than the glass transition point of the low-melting glass contained in the sealing material to remove the resin, which is a binder component, and then heating the coating layer to a temperature equal to or higher than the softening point of the low-melting glass contained in the sealing material.

[0097] Next, the second substrate 12 provided with the pre-fired layer 15a and the first substrate 11 are stacked together with the pre-fired layers 15a facing each other (FIGS. 3A and 3B). An electronic element section 13 is provided on the first substrate 11 according to the specifications of the sealed package 10 (FIGS. 4 and 5).

[0098] Thereafter, the pre-baked layer 15a is irradiated with laser light 16 through the second substrate 12 to perform baking (FIG. 3C). The laser light 16 is irradiated while scanning along the frame-shaped pre-baked layer 15a. By irradiating the entire periphery of the pre-baked layer 15a with the laser light 16, a frame-shaped sealing layer 15 is formed between the first substrate 11 and the second substrate 12. The laser light 16 may also be irradiated onto the pre-baked layer 15a through the first substrate 11.

[0099] The type of laser beam 16 is not particularly limited, and may be a semiconductor laser, a carbon dioxide laser, an excimer laser, a YAG laser, a HeNe laser, etc. The irradiation conditions of the laser beam 16 are selected depending on the thickness, line width, cross-sectional area in the thickness direction, etc. of the pre-baked layer 15a. From the viewpoint of sufficiently melting the pre-baked layer 15a, the output of the laser light 16 is preferably 2 W or more, and more preferably 5 W or more. Moreover, from the viewpoint of suppressing the occurrence of cracks and the like in the first substrate 11 and the second substrate 12, the output of the laser light 16 is preferably 150 W or less, and more preferably 120 W or less.

[0100] In this way, a sealed package 10 is manufactured in which the electronic element section 13 is hermetically sealed between the first substrate 11 and the second substrate 12 by the sealing layer 15 (FIG. 3D).

[0101] Although the method of firing by irradiation with laser light 16 has been described above, the firing method is not necessarily limited to the method of firing by irradiation with laser light 16. As the firing method, other methods can be adopted depending on the heat resistance of the electronic element portion 13, the configuration of the sealed package 10, etc. For example, if the electronic element portion 13 has high heat resistance or if there is no electronic element portion 13, instead of irradiating with laser light 16, the entire assembly as shown in FIG. 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.

[0102] <Organic electroluminescence element> The organic electroluminescence device according to this embodiment includes a first substrate and a second substrate disposed opposite the first substrate, and a sealing layer between the first and second substrates to bond the substrates together. The sealing layer is made of a glass composition, and the glass transition point of the glass composition is 350°C or lower. A reaction layer formed by reaction between at least one of the first substrate and the second substrate and the sealing layer has a thickness of 4 to 25 nm.

[0103] The sealing layer and the reactive layer in the organic electroluminescence element are the same as those described above in the (sealing layer) and (reactive layer) in the <Sealed package>, respectively, and the preferred embodiments are also the same.

[0104] An example of an organic electroluminescent element constituting an OELD will be described below with reference to Fig. 10, but the organic electroluminescent element according to the present invention is not limited to this. Furthermore, the configuration can be appropriately changed as needed within the scope of the present invention.

[0105] An organic electroluminescence element 210 according to this embodiment has a laminated structure 213 laminated on a substrate 211. The laminated structure 213 has, in this order from the substrate 211 side, a cathode 213c, an organic thin film layer 213b, and an anode 213a. The organic electroluminescence element 210 is provided with a glass member 212 placed opposite the substrate 211 so as to cover the outer surface side of the laminated structure 213, and a sealing layer 215 that bonds the substrate 211 and the glass member 212 together. The sealing layer 215 is made of the above-mentioned glass composition, and the glass that constitutes the glass composition has a glass transition point of 350° C. or lower. A reaction layer (not shown) having a thickness of 4 to 25 nm is formed between the sealing layer 215 and at least one of the substrate 211 and the glass member 212. [Example]

[0106] 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 4-1 to 4-6 are examples, and Examples 5-1 to 5-3 are comparative examples. Examples 1-1 to 1-4 and 2-1 to 2-5 are examples of low-melting glass production, and Examples 3-1 to 3-3 are comparative examples.

[0107] [Examples 1-1 to 1-4 and Examples 3-1 to 3-3] (Glass powder manufacturing) Raw materials were prepared and mixed to obtain the compositions shown in mol% in the "Glass Composition" column of Tables 1 and 3, and melted for 1 hour using a platinum crucible in an electric furnace at 1050 to 1150° C. The resulting molten glass was then formed into a thin glass sheet. The thin glass plate was pulverized in a rotary ball mill and classified using a sieve to obtain glass powders of Examples 1-1 to 1-4 and Examples 3-1 to 3-3 having particle sizes of 0.5 to 15 μm.

[0108] [Examples 2-1 to 2-5] (Production of glass powder mixture) The glass powders of Examples 1-2 to 1-4 were mixed in the volume ratios shown in Table 2 to obtain glass powder mixtures of Examples 2-1 to 2-5. The average composition of each glass powder mixture was as shown in Table 2. In Table 2, "Glass 1-2" means the glass powder of Example 1-2, and other similar descriptions have the same meaning.

[0109] The glass transition temperature (Tg) of the obtained glass powder or glass powder mixture of each example was measured as a glass property using a differential thermal analyzer (Rigaku Corporation, ThermoPlus TG8110). The measurement conditions were as follows: in air, using alumina as a reference sample, a heating rate of 10°C / min, and a temperature range of room temperature to 500°C. As mentioned above, the first inflection point was taken as the glass transition temperature. The results obtained are shown in Tables 1 to 3.

[0110] [Table 1]

[0111] [Table 2]

[0112] [Table 3]

[0113] [Examples 4-1 to 4-6 and Examples 5-1 to 5-3] (Glass paste manufacturing) The glass powder or glass powder mixture of each example, a laser-absorbing material (Fe2O3-CuO-MnO), and a low-expansion filler (zirconium phosphate) were blended to the proportions (volume %) shown in Tables 4 and 5 to obtain glass composition powders. Separately, ethyl cellulose (resin) and diethylene glycol mono-2-ethylhexyl ether (solvent) were blended to the proportions (mass %) shown in Table 4 to prepare organic vehicles. The glass composition powder and organic vehicle were then blended in the mass proportions shown in Table 4 and diluted with diethylene glycol mono-2-ethylhexyl ether to obtain a viscosity suitable for screen printing, thereby preparing glass pastes. The particle size of the laser-absorbing material was 0.8 μm, and the particle size of the low-expansion filler was 0.9 μm. In Tables 4 and 5, "Glass 1-1" means the glass powder of Example 1-1, and other similar descriptions have the same meaning.

[0114] (Sealed package production) 11 and 12, the glass paste was applied in a frame shape using a 400-mesh screen to the surface of a glass substrate 32 made of alkali-free glass AN100 (manufactured by AGC, 25 mm × 25 mm × 0.5 mm thick). The substrate was then dried at 120°C for 10 minutes and pre-baked at 420°C to 480°C for 10 minutes to form a pre-baked layer 35a. The pre-baked layer 35a was designed to have a width of approximately 500 μm and a thickness of approximately 4 to 8 μm when used as the sealing layer 35. Thereafter, the glass substrate 31 and the glass substrate 32 provided with the pre-baked layer 35a were overlapped so that the glass substrate 31 and the pre-baked layer 35a were in contact with each other to form an assembly. Furthermore, this assembly was irradiated with a laser beam (semiconductor laser) having a wavelength of 940 nm and a spot diameter of 1.6 mm at a scanning speed of 10 mm / s from the glass substrate 32 side to melt and rapidly solidify the pre-baked layer 35a. As a result, a sealed package 30 was produced in which the glass substrate 32 was bonded to the glass substrate 31 via the sealing layer 35, as shown in FIG. 13 . The laser light output was set to the values ​​shown in Tables 4 and 5, but for Examples 4-3 to 4-6, several outputs were selected and the resulting differences in reaction layer thickness and falling ball strength were examined.

[0115] (Measurement of reaction layer thickness) In the sealed package 30, the thickness of the reaction layer formed by the reaction between the glass substrate 32 and the sealing layer 35 was measured by the following method. The glass substrate 31 was peeled off from the sealed package 30. Next, an etching solution was prepared by diluting a nitric acid aqueous solution (60%) with distilled water at a ratio of 1:1, and the sample from which the glass substrate 31 had been removed was immersed in the etching solution for 48 hours to remove the sealing layer and reaction layer. Next, the sample was washed with distilled water and wiped. Only the glass substrate 32 is obtained by the above process, and if a reaction layer has been formed, the reaction layer will remain on the surface as a recess 36 after formation, as shown in Figure 18. Using a white light interferometer (Zygo New View 6200, manufactured by Zygo Corporation, USA), interference fringes on the side of the glass substrate 32 where the sealing layer had been formed, i.e., the side having the recess 36, were imaged, and the thickness of the reaction layer was obtained based on height information obtained from the interference fringes.

[0116] The specific measurement method was as follows: A 0.5x zoom lens and a 10x objective lens were used. On the main surface of the glass substrate 32 on the side where the reaction layer is formed, i.e., the side that was in contact with the sealing layer, the height of the region where the reaction layer, i.e., the recessed portion 36, is not formed is defined as the glass thickness Ha. On the other hand, the height of the frame-shaped region where the reaction layer, i.e., the recessed portion 36 is formed is defined as the glass thickness Hb. The reaction layer thickness refers to the average value of the difference between Ha and Hb (Ha - Hb) measured at three locations. Here, Ha is the height measured at any location in the region where the recess 36 is not formed within a 1.4 mm range, and the average value is defined as the glass thickness Ha. Hb is a value calculated using the following method. First, the height of the recess in the width direction α is measured with any point in the region where the recess 36 is formed as the center. Next, a moving average is taken at three points for the waveform of the measured height of the recess in the width direction α. ​​In the height waveform for which the moving average is taken, the lowest point of the height, i.e., the point where the recess is deepest, is set as the center, and the height is measured within a range of 1.4 mm in the direction β perpendicular to the width direction of the recess. The average value of the measured heights is defined as the glass thickness Hb. The (Ha-Hb) at the first location is obtained from the Ha and Hb obtained above. The same measurement is repeated at the other two locations, and the average of the (Ha-Hb) values ​​obtained at the three locations is taken as the thickness of the reaction layer. When calculating one location (Ha - Hb), the areas where Ha and Hb are measured are selected to be close to each other, taking into consideration the case where the thickness of the glass substrate before the reaction layer is formed is not uniform.

[0117] (Measurement of falling ball strength) To evaluate the impact resistance, the ball drop strength was measured. As shown in FIGS. 14 and 15, the sealed package 30 was used as a test piece for strength evaluation, and a support substrate 46 measuring 100 mm×100 mm×3.4 mm thick was fixed to one surface of the package with a thermosetting adhesive 43. 16, a weight ball 47 was dropped from the side of the support substrate 46 where the strength evaluation test piece was not bonded toward the area where the strength evaluation test piece was bonded. The mass and drop height 48 of the weight ball 47 were changed, and the drop energy at that time was calculated as the drop ball strength using the following formula. The drop energy was increased, and the maximum drop energy at which the pair of glass substrates 31, 32 of the sealed package 30 did not peel off was measured as the drop ball strength. Note that the above phrase "the pair of glass substrates 31, 32 of the sealed package 30 did not peel off" means that the pair of glass substrates 31, 32 did not peel off in two or more of the three tests. The measurement results of the drop ball strength are shown in Tables 4 and 5. The relationship between the falling ball strength and the thickness of the reaction layer is summarized in Figure 17. Falling ball strength [mJ] = Mass of weight ball [g] × Fall height [m] × Gravitational acceleration [m / s 2 ]

[0118] [Table 4]

[0119] [Table 5]

[0120] In the sealed packages of Examples 4-1 to 4-6, which are working examples, a reaction layer of sufficient thickness was formed, and they exhibited excellent impact resistance. On the other hand, in the sealed packages of Examples 5-1 to 5-3, which are comparative examples, although a low-melting point glass with a glass transition point of 350°C or less was used for the sealing layer, no reaction layer was formed, or even if formed, the reaction layer was thin, resulting in poor impact resistance. [Explanation of symbols]

[0121] 10: Sealed package 11: First substrate 12: Second board 13: Electronic element section 15: Sealing layer 15a: Pre-fired layer 16: Laser light 30: Sealed package 31, 32: Glass substrate 35: Sealing layer 35a: Pre-baked layer 36: Concave part 46: Support substrate 47: Weight ball 48: Fall height 100: Sealing layer 100a: Pre-fired layer 101: V2O5-TeO2-ZnO glass 102: Bi2O3-ZnO-B2O3 glass 210: Organic electroluminescence element 211: Substrate 212: Glass components 213: Laminated structure 213a:Anode 213b: Organic thin film layer 213c: Cathode 215: Sealing layer

Claims

1. A sealed package including 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 and bonding the first substrate to the second substrate, the sealing layer is made of a glass composition, the glass composition has a glass transition temperature of 350°C or less; a reaction layer is formed by reaction between at least one of the first substrate and the second substrate and the sealing layer, The reaction layer has a thickness of 4 to 25 nm, The glass contains V 2 O 5 as a main component, and the content of Bi 2 O 3 is 0.5 to 10%, and the total content of V 2 O 5 , TeO 2 and ZnO is 78.0 to 89.0%, expressed in mole percent on an oxide basis.

2. The sealed package of claim 1 , wherein the glass composition further comprises at least one of a low expansion filler and a laser absorbing material.

3. 3. The sealed package according to claim 1, wherein at least one of the first substrate and the second substrate is a glass substrate.

4. 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 and bonding the first substrate to the second substrate; the sealing layer is made of a glass composition, the glass composition has a glass transition temperature of 350°C or less; a reaction layer is formed by reaction between at least one of the first substrate and the second substrate and the sealing layer, At least one of the reaction layers has a thickness of 4 to 25 nm; The organic electroluminescence element comprises the glass containing V 2 O 5 as a main component, and the content of Bi 2 O 3 is 0.5 to 10%, and the total content of V 2 O 5 , TeO 2 and ZnO is 78.0 to 89.0%, expressed in mole percent on an oxide basis.

5. 5. The organic electroluminescence device according to claim 4, wherein the glass composition further comprises at least one of a low expansion filler and a laser absorbing material.

6. 6. The organic electroluminescence device according to claim 4, wherein at least one of the first substrate and the second substrate is a glass substrate.

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