JP6927258B2 - Lead-free low melting point glass composition and lead-free glass composite material containing it, lead-free glass paste and sealing structure - Google Patents

Description

The present invention relates to a lead-free low melting point glass composition, a lead-free glass composite material containing the same, a lead-free glass paste, and a sealing structure.

For vacuum-insulated double glazing panels, plasma display panels, organic EL display panels, display panels such as fluorescent display tubes, and electrical and electronic components such as crystal transducers, IC ceramic packages, and semiconductor sensors, which are applied to window glass, etc. , A low melting point glass composition and a glass composite material containing particles of low thermal expansion ceramics and glass beads are used for sealing and bonding. This glass composite is often used in the form of a glass paste. The glass paste is applied to the base material by a screen printing method, a dispenser method, or the like, dried, and then fired to seal or bond the glass paste. At the time of sealing or bonding, the low melting point glass composition softens and flows to adhere to or adhere to the sealed member or the bonded member.

As the low melting point glass composition, a PbO-B ₂ O ₃ system low melting point glass composition containing a very large amount of lead oxide has been widely applied. This PbO-B ₂ O ₃ system low melting point glass composition has a low softening point of 350 to 400 ° C., exhibits good softening fluidity at 400 to 450 ° C., and has relatively high chemical stability. ing.

However, in recent years, the trend of green procurement and green design has intensified worldwide, and safer materials have been required. For example, in Europe, the European Union (EU) Directive (RoHS Directive) on restrictions on the use of specified hazardous substances in electronic and electrical equipment came into effect on July 1, 2006. In the RoHS Directive, lead, mercury, cadmium and hexavalent chromium are designated as prohibited substances. Therefore, the above-mentioned PbO-B ₂ O ₃ system low melting point glass composition is practically difficult to use.

Therefore, the development of a new low melting point glass composition containing no lead is underway.

Patent Document 1 contains vanadium oxide, tellurium oxide, iron oxide and phosphorus oxide, and in terms of oxide, V ₂ O ₅ + TeO ₂ + Fe ₂ O ₃ + P ₂ O ₅ ≥ 90, and V ₂ O ₅ > TeO. _{Low melting point glass having a relationship of 2} > Fe ₂ O ₃ > P ₂ O ₅ (in the two equations, the unit is "mass%") is disclosed. This low melting point glass has a softening point of 410 ° C. or lower and a thermal expansion coefficient of 100 × ^10-7 / ° C. or lower, and has excellent moisture resistance.

Japanese Patent No. 5733279

Vacuum-insulated double glazing panels and the like applied to window glass and the like are required to have an airtight sealing portion and an adhesive portion having extremely high reliability. For example, in an unsaturated high-speed accelerated life test (HAST: Highly Accelerated Stress Test) with a temperature of 120 ° C., a humidity of 85%, and a pressure of 2 atm, erosion of the sealing part and the adhesive part, leakage and peeling due to the erosion, etc. occur. You need to avoid it.

The lead-free low melting point glass composition disclosed in Patent Document 1 and the lead-free glass composite material containing the same are attractive materials having excellent durability in the above-mentioned HAST. However, on the other hand, soda lime (SiO _2- Na ₂ O-CaO system) glass base material, borosilicate (SiO _2- B ₂ O _3- Na ₂ O system) glass base material, quartz (SiO ₂ ) glass base. Insufficient adhesion and adhesion to sealed and bonded members such as materials, silicon (Si) base materials, alumina (Al ₂ O ₃ ) base materials, and silicon nitride (Si ₃ N _{4) base materials.} Therefore, there is a problem that it is easily peeled off from the interface of these members.

An object of the present invention is to improve adhesiveness and adhesion in a lead-free low melting point glass composition of _{V 2} O _5- TeO _2- Fe ₂ O _3- P ₂ O _{5 system.}

The lead-free low melting point glass composition of the present invention contains vanadium oxide, tellurium oxide, iron oxide, phosphorus oxide and lithium oxide, and satisfies the following two relational expressions (1) and (2) in terms of oxide.

[V ₂ O ₅ ] + [Te _{O 2} ] + [Fe ₂ O ₃ ] + [P ₂ O ₅ ] + [Li ₂ O] ≧ 90… (1)
[V ₂ O ₅ ] ≧ [Te _{O 2} ] ＞ [Fe ₂ O ₃ ] ≧ [P ₂ O ₅ ] ≧ [Li ₂ O]… (2)
(In the formula, [X] represents the content of component X, and its unit is "mol%". The same shall apply hereinafter.)

According to the present invention, in a V ₂ O _5- TeO _2- Fe ₂ O _3- P ₂ O ₅ series lead-free low melting point glass composition, adhesiveness and adhesion can be improved.

It is a graph which shows the result of the typical differential thermal analysis (DTA) peculiar to glass. It is a graph which shows the typical thermal expansion curve of a lead-free glass composition. It is a schematic plan view which shows the sealing structure of Example 1. FIG. FIG. 3A is a cross-sectional view taken along the line AA of FIG. 3A. It is a figure which shows a part of the manufacturing process of the sealing structure of Example 1. It is a figure which shows a part of the manufacturing process of the sealing structure of Example 1. It is a schematic plan view which shows the vacuum insulation multi-layer glass panel of Example 3. FIG. 6A is a cross-sectional view taken along the line AA of FIG. 6A. It is a schematic plan view which shows a part of the manufacturing method of the vacuum insulation double glazing panel of Example 3. FIG. FIG. 7A is a cross-sectional view taken along the line AA of FIG. 7A. It is a schematic plan view which shows a part of the manufacturing method of the vacuum insulation double glazing panel of Example 3. FIG. 8A is a cross-sectional view taken along the line AA of FIG. 8A. It is schematic cross-sectional view which shows a part of the manufacturing process of the vacuum insulation double glazing panel of Example 3. FIG. It is a sealing temperature profile in the manufacturing process of the vacuum insulation double glazing panel of Example 3. It is a schematic plan view which shows the OLED display of Example 4. FIG. 11A is a cross-sectional view taken along the line AA of FIG. 11A. It is a schematic plan view which shows a part of the manufacturing process of the OLED display of Example 4. 12A is a cross-sectional view taken along the line AA of FIG. 12A. It is a schematic plan view which shows a part of the OLED display manufacturing process of Example 4. 13A is a cross-sectional view taken along the line AA of FIG. 13A. It is a schematic cross-sectional view which shows a part of the manufacturing method of the OLED display of Example 4. It is a schematic cross-sectional view which shows the manufacturing method of the crystal oscillator package of Example 5. It is a schematic cross-sectional view which shows the crystal oscillator package of Example 5.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the embodiments taken up here, and can be appropriately combined and improved without changing the gist.

(Glass composition)
In the glass composition, in general, the lower the characteristic temperature such as the transition point, the yield point, and the softening point, the better the softening fluidity at the low temperature. On the other hand, if the characteristic temperature is lowered too much, the crystallization tendency becomes large and it becomes easy to crystallize at the time of heating and firing. This crystallization is a factor that reduces the softening fluidity at low temperatures. Further, the lower the characteristic temperature of glass, the lower the chemical stability such as moisture resistance, water resistance, acid resistance, alkali resistance, and salt water resistance. Furthermore, the impact on the environmental load tends to increase. For example, in the conventional PbO-B ₂ O ₃ system low melting point glass composition, the higher the harmful PbO content, the lower the characteristic temperature can be, but the crystallization tendency is large and the chemical stability is lowered, and further. The impact on the environmental load will also increase.

The present inventor has substantially yet lead-free low-melting-point glass composition containing no lead, has a conventional PbO-B ₂ O ₃ -based low melting glass composition and equal or better softening fluidity (equivalent The lead-free low melting point glass composition, which has the following softening points), has good adhesiveness and adhesion, and has good chemical stability such as moisture resistance, was intensively studied. As a result, the present inventor has determined that the above requirements are simultaneously satisfied by adding lithium in _{the V 2} O _5- TeO _2- Fe ₂ O _3- P ₂ O _{5 series lead-free low melting point glass composition.} The heading, the present invention was completed.

Specifically, the lead-free low melting point glass composition according to the present invention contains vanadium oxide, tellurium oxide, iron oxide, phosphorus oxide and lithium oxide as main components, and the content of these main components is converted into oxides. , Satisfies the following two relational expressions (1) and (2).

[V ₂ O ₅ ] + [Te _{O 2} ] + [Fe ₂ O ₃ ] + [P ₂ O ₅ ] + [Li ₂ O] ≧ 90… (1)
[V ₂ O ₅ ] ≧ [Te _{O 2} ] ＞ [Fe ₂ O ₃ ] ≧ [P ₂ O ₅ ] ≧ [Li ₂ O]… (2)
Here, in the above inequality, the content of oxide X is expressed as [X] (the same applies hereinafter). The unit is "mol%" (the same shall apply hereinafter). “Mole%” is calculated by converting the content of each component contained in the glass composition into an oxide as a ratio to the entire glass composition.

Here, "lead-free" in the present invention means that the lead (Pb) content is 1000 ppm or less, which is an allowable range in the RoHS Directive.

_{The functions of the main components V 2} O ₅ , TeO ₂ , Fe ₂ O ₃ , P ₂ O ₅ and Li ₂ O in the lead-free low melting point glass composition of the present invention will be described below.

The glass structure of the lead-free low melting point glass composition containing V ₂ O ₅ , TeO ₂ , Fe ₂ O ₃ , P ₂ O ₅ and Li ₂ O as main components has a layered structure consisting of _{V 2} O ₅ and Te _{O 2.} It is considered that _{Fe 2} O ₃ , P ₂ O ₅ and Li ₂ O are present between the layers. It is considered that TeO _{2 in the} layer and Fe ₂ O ₃ , P ₂ O ₅ and Li ₂ O between the layers are bound to _{V 2} O _{5 forming a layered structure.}

TeO ₂ is a vitrifying component for vitrification, and glass cannot be formed unless _{TeO 2 is contained.} Further, TeO ₂ is also a component that improves softening fluidity at a low temperature, that is, a component that lowers a characteristic temperature such as a softening point. When _{the content of TeO 2} is small, it is difficult to reduce the crystallization tendency, and good softening fluidity at a low temperature cannot be obtained.

On the other hand, if the content of _{TeO 2 is larger than the content of V 2} O ₅ , the coefficient of thermal expansion may become too large, or the chemical stability such as moisture resistance may decrease. Therefore, the content of _{TeO 2} needs to be equal to or less than the content of _{V 2} O _5.

Fe ₂ O ₃ contributes to improvement of chemical stability such as moisture resistance and reduction of coefficient of thermal expansion. However, when the content of _{Fe 2} O _{3 is equal to or higher than the content of Te O 2} , problems such as a significant increase in the crystallization tendency and a significant increase in the characteristic temperature such as a softening point occur. Therefore, the content of _{Fe 2} O ₃ needs to be less than the content of _{Te O 2.}

P ₂ O ₅ is _{also a vitrifying component of V 2} O ₅ and greatly contributes to the reduction of crystallization tendency. It also has the effect of reducing the coefficient of low expansion. However, if the content of _{P 2} O _{5 is larger than the content of Fe 2} O ₃ , there arises a problem that the chemical stability such as moisture resistance is significantly lowered. Therefore, the content of _{P 2} O ₅ needs to be in a range not exceeding the content of _{Fe 2} O _3.

Li ₂ O greatly contributes to obtaining strong adhesiveness and adhesiveness to the member to be sealed and the member to be adhered. In the glass structure, it ^{exists in the state of Li + , and when the Li +} is diffused to the sealed member or the bonded member at the time of sealing or bonding, excellent adhesiveness and adhesion can be obtained. Conceivable. Further, although it depends on the member to be sealed and the member to be adhered, the effect of Li ₂ O can be obtained even if it is contained in a very small amount. However, if _{the content is larger than the content of P 2} O ₅ , there is a problem that the chemical stability such as moisture resistance is lowered. Therefore, the content of _{Li 2} O needs to be equal to or less than the content of _{P 2} O _5.

Furthermore, further research will be conducted on the relationship between _{the components (V 2} O ₅ , TeO ₂ ) existing in the layer of the layered structure and the components (Fe ₂ O ₃ , P ₂ O ₅ , Li _{2 O) existing between the layers.} As a result, it was found that it is preferable to satisfy the following relational expression (3).

[TeO ₂ ] ≧ [Fe ₂ O ₃ ] + [P ₂ O ₅ ] + [Li ₂ O] ≧ 1/2 [V ₂ O ₅ ]… (3)
Note that 1/2 [V ₂ O ₅ ] means 1/2 × [V ₂ O ₅ ], that is, half the value of _{[V 2} O _5].

In the above _{V 2 O 5 -TeO 2 -Fe 2} O 3 -P 2 O 5 -Li 2 O system lead-free low-melting-point glass composition, the preferred composition range of TeO ₂ and Li ₂ O is, the content of TeO ₂ Is 30 mol% or more and 40 mol% or less, and _{the content of Li 2} O is 0.1 mol% or more and 10 mol% or less.

Further, the preferable composition range of _{V 2} O ₅ , Fe ₂ O ₃ and P ₂ O _{5 is that the content of V 2} O ₅ is 33 mol% or more and 42 mol% or less, and _{the content of Fe 2} O ₃ is 7 mol%. 16 mol% or more and P ₂ O ₅ is 6 mol% or more and 15 mol% or less.

Furthermore, the _{V 2 O 5 -TeO 2 -Fe 2} O 3 -P 2 O 5 -Li 2 O system lead-free low-melting-point glass composition, as an additional component, an alkali metal oxide other than lithium oxide, an alkaline earth metal It is desirable to contain any one or more of oxides, zinc oxide, molybdenum oxide and tungsten oxide. The content (mol%) of these additional components is Ln ₂ O + RnO + ZnO + MoO ₃ + WO ₃ ≤ 10.

The above can be summarized as follows.

It is desirable that the lead-free low melting point glass composition satisfies the following two relational expressions (4) and (5).

30 ≤ [TeO ₂ ] ≤ 40 ... (4)
0.1 ≤ [Li ₂ O] ≤ 10 ... (5)
It is desirable that the lead-free low melting point glass composition satisfies the following three relational expressions (6) to (8).

33 ≤ [V ₂ O ₅ ] ≤ 42… (6)
7 ≤ [Fe ₂ O ₃ ] ≤ 16… (7)
6 ≤ [P ₂ O ₅ ] ≤ 15… (8)
The lead-free low melting point glass composition further contains any one or more of alkali metal oxides other than lithium oxide, alkaline earth metal oxides, zinc oxide, molybdenum oxide and tungsten oxide, and has the following relational expression (9). It is desirable to meet.

[Ln ₂ O] + [RnO] + [ZnO] + [MoO ₃ ] + [WO ₃ ] ≤ 10… (9)
Here, in the above inequality, Ln represents an alkali metal element other than Li, and Rn represents an alkaline earth metal element.

It is desirable that the lead-free low melting point glass composition has a density of 3.6 g / cm ³ or more and 4.0 g / cm ³ or less, and a second endothermic peak temperature of 400 ° C. or less by differential thermal analysis.

As will be described in detail in the explanation of FIG. 1 in the latter part, the present inventor compares the results of differential thermal analysis (DTA) with the temperature based on the definition by viscosity for the transition point, yield point and softening point of the glass. It was confirmed that the second endothermic peak temperature by DTA was substantially equal to the softening point measured as the temperature corresponding to the viscosity. Therefore, in the present specification, the second endothermic peak temperature by DTA is defined as _{"softening point T s".}

Here, the characteristic temperature of the glass in the present invention will be described. In the present invention, the characteristic temperature was measured by DTA.

Generally, as the DTA of glass, glass particles having a particle size of about several tens of μm are used, and high-purity alumina (α-Al ₂ O ₃ ) particles are used as a standard sample, and the temperature is raised to 5 ° C./min in the atmosphere. Measure at speed.

FIG. 1 is an example of a typical DTA curve peculiar to glass. The horizontal axis represents the temperature of the standard sample, and the vertical axis represents the temperature difference (potential difference) between the glass sample to be measured and the standard sample.

In the figure, when heating the glass above the heating rate, the heat absorption starting from the transition point T _g, reaches the yield point M _g corresponding to a first endothermic peak temperature. Then, the temperature difference becomes small once, and then the temperature difference becomes large again to reach the _{softening point T s corresponding to the second endothermic peak temperature.}

When further heated _{, heat generation starts from the crystallization temperature T cry} and reaches the heat generation peak. This exothermic peak is due to crystallization, and the temperature at which the exotherm starts is called the _{crystallization temperature T cry.} Although not shown, the temperature corresponding to the exothermic peak is referred to as the crystallization peak temperature _Tcry-p . Transition The T _g is the starting temperature of the first endothermic peak, the yield point M _g is a first endothermic peak temperature. Each characteristic temperature is usually obtained by the tangential method.

Strictly speaking, the transition point T _g, yield point M _g and a softening point T _s is defined by the viscosity of the glass. The T _g ¹⁰ 13.3 poise, _{M g} is ¹⁰ 11.0 poise, the _{T s} is the temperature corresponding to ¹⁰ 7.65 poise.

The crystallization tendency is _{determined from the difference (absolute value) between the softening point T s} and the crystallization temperature T _cry, and the height of the exothermic peak due to crystallization, that is, the calorific value thereof.

First, if the difference (absolute value) between the softening point T _s and the crystallization temperature T _cry is large, even if the glass reaches a temperature exceeding the _{softening point T s} , the glass is softened and flowed in a temperature range that does not reach _{T cry.} It becomes easy. Further, if the calorific value at the time of crystallization is small, when the temperature _{reaches T cry} by heating at a constant heating rate, it is unlikely that an uncontrollable temperature rise due to the heat generation will occur, so that the progress of crystallization Can be suppressed.

_Therefore, it can be said the increase in the high temperature i.e. _T cry -T _s of _{T cry,} a decrease of the crystallization calorific value as indicating glass difficult to crystallize. That is, if glass that is determined to have a small crystallization tendency is used, it becomes easy to form a desired sealing portion or the like.

The firing temperature when sealing or bonding various parts using a conventional leaded low melting point glass composition is the type, content and particle size of the ceramic particles and glass beads contained, and the rate of temperature rise. Although it is affected by firing conditions such as atmosphere and pressure, it is usually set to be about 40 ° C. higher than the _{softening point T s.} At this firing temperature, the leaded low melting point glass composition has good softening fluidity without crystallization.

Lead-free low-melting-point glass composition of the present invention, compared with the conventional leaded low melting glass composition, transition point T _g, the characteristic temperature of the yield point M _g and a softening point T _s is the same or less, moreover viscosity gradient big. Therefore, good softening fluidity can be obtained at a temperature higher than the softening point T _{s by about 30 ° C.} That is, the lead-free low melting point glass composition of the present invention has a softening point T _s of 400 ° C. or lower and can be fired at 430 ° C. or lower. As a result, the impact on the environmental load is reduced, the thermal damage of the sealed structure is reduced (higher functionality), productivity is improved (tact reduction), and the reliability of the sealed part and the bonded part is improved. Can be improved.

(Lead-free glass composite material and lead-free glass paste)
The lead-free glass composite material includes the lead-free low melting point glass composition of the present invention, ceramic particles and glass beads.

Hereinafter, lead-free glass composite materials containing ceramic particles and glass beads will be described. The glass beads refer to glass particles having an average particle size of 50 μm or more.

The lead-free glass composite material containing ceramic particles and glass beads preferably contains 40% by volume or more and less than 100% by volume of a lead-free low melting point glass composition, and more than 0% by volume and 60% by volume or less of ceramics. By setting the lead-free low melting point glass composition to 40% by volume or more or the ceramics to 60% by volume or less, the lead-free low melting point glass composition can maintain good softening fluidity, and highly reliable sealing and adhesion can be achieved. It will be possible.

From the viewpoint of suppressing crystallization, ceramics include zirconium tungstate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) ₂ ), quartz glass (SiO ₂ ), and borosilicate glass (SiO _2- B ₂ O ₃ system). ), soda lime glass _{(SiO 2} -Na ₂ O-CaO-based), beta-eucryptite _{(Li 2 O · Al 2 O} 3 · 2SiO 2), cordierite _{(2MgO · 2Al 2 O 3 ·} 5SiO 2), zirconium silicate (ZrSiO _4), alumina _{(Al 2 O} 3), mullite _{(3Al 2 O 3 · 2SiO 2} ), and preferably contains any of the niobium oxide _(Nb 2 _{O 5).} In particular, ceramics effective for low thermal expansion of lead-free glass composite materials are _{either zirconium tungrate phosphate (Zr 2} (WO ₄ ) (PO ₄ ) ₂ ) or quartz glass (SiO ₂ ). The preferable content thereof is 30% by volume or more and 60% by volume or less.

Examples of the glass beads include soda lime glass (SiO _2- Na ₂ O-CaO glass), borosilicate glass (SiO _2- B ₂ O _3- Na ₂ O glass), quartz glass (SiO ₂ ) and the like. Can be used.

The lead-free glass paste contains a lead-free glass composite material containing a lead-free low melting point glass composition, a binder, and a solvent. It is preferable to use polypropylene carbonate as the binder and dihydrotermineto or carbitol acetate as the solvent. By combining the binder and the solvent as described above, it is possible to suppress the crystallization of the lead-free low melting point glass composition and reduce the bubbles remaining after heating and firing. Further, if necessary, a viscosity modifier, a wetting agent, or the like can be added to adjust the stability and coatability of the lead-free glass paste.

(Sealing structure)
Lead-free glass composite materials and lead-free glass pastes are used in vacuum-insulated double glazing panels, plasma display panels, organic EL display panels, display panels such as vacuum fluorescent displays, crystal transducers, IC packages, etc., which are applied to window glass and the like. It is suitably used for sealing and adhering package devices such as MEMS.

The sealing structure of the present invention is formed by using a lead-free glass composite material, and includes a sealing portion forming at least a part of an internal space separated from the outside and a boundary between the outside and the outside. Here, the content of the lead-free low melting point glass composition contained in the lead-free glass composite material is preferably 40% by volume or more.

Hereinafter, the present invention will be described in detail based on specific examples. However, the present invention is not limited to the examples taken up here, and includes variations thereof.

In Example 1, a V ₂ O _5- TeO _2- Fe ₂ O _3- P ₂ O ₅ series lead-free glass composition was prepared, and the effect of the glass composition on the glass properties was examined.

(Preparation of lead-free glass composition)
Table 1 shows the compositions of the lead-free glass compositions A-01 to A-69 of Examples. A-01 to A-69 are _{lead-free glass compositions containing V 2} O ₅ , TeO ₂ , Fe ₂ O ₃ , P ₂ O ₅ and Li ₂ O as main components and essential components.

Table 2 shows the compositions of B-01 to B-07 of Comparative Examples.

These compositions are the proportions blended when making the glass.

As the starting materials of the main component, purity Shinko Chemical Industry 99% or more, Ltd. of _V 2 _{O 5} and TeO _2, and Co. Kojundo Chemical Laboratory Co. of _{Fe 2 O 3, P 2 O} 5 , Li ₂ CO ₃ , Na ₂ CO ₃ , K ₂ CO ₃ , MgO, CaCO ₂ , SrCO ₃ , BaCO ₃ , ZnO, MoO ₃ and WO ₃ powders were used.

Each starting material powder was weighed, blended, mixed, and put into a platinum crucible so as to have a total of about 200 g. A platinum crucible containing the raw material mixed powder was placed in a glass melting furnace and heated to 900 to 950 ° C. at a heating rate of about 10 ° C./min. In order to make the composition of the melt in the platinum crucible uniform, the mixture was held for 1 hour while stirring with an alumina rod. After that, the platinum crucible was taken out from the glass melting furnace, and the melt was poured into a stainless steel mold that had been preheated to about 150 ° C., and A-01 to A-69 of Example and B-01 to B-07 of Comparative Example were poured. Were prepared respectively.

(Measurement of density)
The prepared lead-free glass compositions A-01 to A-69 and B-01 to B-07 were roughly pulverized with a stamp mill and then pulverized with a jet mill to an under 45 μm. Using the glass powder, the density of each glass was measured by a pycnometer method in helium gas.

(Measurement of characteristic temperature)
Using the same glass powder used for the density measurement, DTA was performed at a heating rate of 5 ° C./min in the atmosphere. As a result, a DTA curve similar to that in FIG. 1 was obtained. The macro cell type was used for DTA. Transition point of the obtained DTA curve from the lead-free glass composition T _g, was measured sag M _g and a softening point T _s.

(Measurement of coefficient of thermal expansion)
Heating the Pb-free glass composition A-01~A-69 and B-01 to B-07 prepared in the temperature range of transition point _{T g} ~ sag _{M g} by DTA, remove residual thermal strains by slow cooling Then, it was processed into a square pillar of 4 × 4 × 20 mm. Using this, the thermal expansion curve of each lead-free glass composition was measured with a thermal expansion meter at a heating rate of 5 ° C./min in the atmosphere. A cylindrical quartz glass having a diameter of 5 × 20 mm was used as a standard sample.

FIG. 2 is a graph showing a thermal expansion curve of a typical lead-free glass composition. The amount of elongation on the vertical axis in the figure is a value obtained by subtracting the amount of elongation of quartz glass, which is a standard sample.

As shown in this figure, the lead-free glass composition elongates with heating, and remarkable elongation begins at _{the transition temperature TG.} This transition temperature _TG substantially coincides with the transition point T _{g obtained from DTA.}

Further heating reaches the _{deformation temperature AT. Above AT} , it apparently shrinks due to thermal deformation of the lead-free glass composition.

The coefficient of thermal expansion of glass is generally measured from the gradient in the temperature range _{from room temperature to less than TG.} Therefore, for both the lead-free glass compositions of Examples A-01 to A-69 and Comparative Examples B-01 to B-07, the coefficient of thermal expansion was calculated from the gradient in the temperature range of 30 to 250 ° C.

(Evaluation of chemical stability (moisture resistance))
The chemical stability of the prepared lead-free glass compositions A-01 to A-69 and B-01 to B-07 is an unsaturated high-speed accelerated life test (HAST:) at a temperature of 120 ° C., a humidity of 85%, and a pressure of 2 atm. It was evaluated by the moisture resistance according to Highly Accelerated Pressure Test).

The evaluation sample was carried out by HAST for 48 hours using the same prismatic glass used for the thermal expansion measurement, and the degree of corrosion of each lead-free glass composition was observed. When almost no corrosion was observed, it was judged as "○", and when corrosion was clearly observed, it was judged as "×".

Note that transition point _{T g} is _{313 ℃, 84PbO-13B 2 O} 3 yield point _{M g} is 332 ° C. and a softening point _{T s} is a conventional leaded glass composition is 386 ℃ -2SiO ₂ -1Al 2 O ₃ When (% by mass) HAST was carried out in the same manner, corrosion was observed, and the moisture resistance was unacceptable "x".
(Evaluation of softening fluidity and adhesiveness)
The softening fluidity and adhesiveness of the prepared lead-free glass compositions A-01 to A-69 and B-01 to B-07 are the button flow of the powder compact prepared using the same glass powder used for the density measurement. Evaluated in the test.

The powder compact was molded into a cylindrical shape having a diameter of 12 mm and a height of about 3 mm under the condition of ^{500 kg / cm 2} using a mold and a hand press. A powder compact placed on a soda lime (SiO _2- Na ₂ O-CaO system) glass substrate is introduced into an electric furnace, and the temperature rises from room temperature to 30 _{from the softening point T s at a temperature rise rate of 10 ° C./min in the air.} The mixture was heated to a temperature as high as about ° C., held for 30 minutes, and then cooled in a furnace to evaluate the softening fluidity, adhesiveness, and crystallization state.

Regarding the softening fluidity, if the powder compact is satisfactorily softened and fluidized, the result is "○". If it was sufficient, it was judged as rejected "x".

Regarding the adhesiveness, if the powder compact is softened and flows and adheres to and adheres to the soda lime glass substrate, it passes "○", and even if it softens and flows, the interface is easily peeled off from the soda lime glass substrate. In some cases or when the softening flow was insufficient due to crystallization and the glass substrate was easily peeled off from the soda lime glass substrate, the result was judged as "x".

Note that transition point _{T g} is 313 ° C., yield point _{M g} is 332 ° C., a softening point _{T s} is a conventional leaded glass composition is _{386 ℃ 84PbO-13B 2 O 3} -2SiO 2 -1Al 2 O 3 When the same button flow test was carried out at (mass%) at 430 ° C., both the softening fluidity and the adhesiveness were acceptable. However, cracks were observed due to the large difference in thermal expansion from the soda lime glass substrate. The occurrence of this crack can be counteracted by mixing low thermal expansion ceramic particles such as lead titanate into the powder of the leaded glass composition.

(Preparation and evaluation of sealed structure)
A sealed structure was prepared using a lead-free glass composite material containing the lead-free glass compositions shown in Tables 1 and 2 and low thermal expansion ceramic particles. Then, HAST was carried out for 48 hours using this sealing structure. The conditions for HAST were a temperature of 120 ° C., a humidity of 85%, and a pressure of 2 atm in the same manner as described above. Further, for the sealed structure in which no abnormality was observed after HAST, a immersion test was carried out for 30 minutes with a powerful ultrasonic cleaner.

FIG. 3A is a plan view of the sealing structure.

As shown in FIG. 3A, in the sealing structure, the glass composite material 5 is installed on the peripheral edge of a 50 mm × 50 mm glass substrate 1 having a thickness of 3 mm. A spacer 6 is arranged inside the glass composite material 5.

FIG. 3B is a cross-sectional view taken along the line AA of FIG. 3A.

As shown in FIG. 3B, the sealing structure uses a glass substrate 2 having the same dimensions as the glass substrate 1. A glass composite material 5 and a spacer 6 are sandwiched between the two glass substrates 1 and 2. As a result, the internal space 7 is formed. The glass composite material 5 contains a lead-free glass composition 3 and low thermal expansion ceramic particles 4. For the glass substrates 1 and 2, soda lime glass (SiO _2- Na ₂ O-CaO-based glass) having a ^{coefficient of thermal expansion of 88 × 10 -7 / ° C. was used.}

The heating temperature at the time of sealing, was 30 ° C. about a temperature higher than the T _S of the Pb-free glass composition 3.

FIG. 4 is a diagram showing a part of a manufacturing process of the sealed structure.

FIG. 4 shows a coating / firing process.

The glass composite material paste 8 prepared by mixing the particles of the lead-free glass composition 3, the low thermal expansion ceramic particles 4, the binder, and the solvent was applied to the outer peripheral portion of the glass substrate 1 by the dispenser method. The dried at 0.99 ° C., then heated at a heating rate of about 5 ° C. / minute in air to a temperature range of transition point T _{g ~} yield point M _g of Pb-free glass composition 3, was held for 30 minutes. Then, the glass composite material 5 was formed on the outer peripheral portion of the glass substrate 1 by further heating to a temperature higher than the _{softening point T s} by about 30 ° C. at the same rate of temperature rise and holding for 30 minutes for firing.

As the particles of the lead-free glass composition 3, a glass powder under 45 μm, which was also used for measuring the density and the characteristic temperature, was used. As the low thermal expansion ceramic particles 4, zirconium tungate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) ₂ ) having an average particle size of about 15 μm was used. The density of this ceramic is 3.8 g / cm ³ , and the coefficient of thermal expansion is −38 × ^10-7 / ° C. The blending ratio of the lead-free glass composition 3 and the low thermal expansion ceramic particles 4 was adjusted so that the ^{coefficient of thermal expansion was about 70 × 10 -7 / ° C.} This is to take into consideration the coefficient of thermal expansion of the glass substrates 1 and 2, that is, soda lime glass to be used, and to prevent tensile stress from being applied to the glass composite material 5 of the sealing portion as much as possible.

In order to minimize the number of air bubbles remaining in the glass composite material 5 of the sealing portion, polypropylene carbonate was used as the binder and dihydrotermineto or carbitol acetate was used as the solvent. Although various binders and solvents were also examined, it was the best combination with few residual bubbles for the lead-free glass composition of the present invention and the lead-free glass composite material containing the same.

The glass composite material paste 8 was prepared so that the solid content of the particles of the lead-free glass composition 3 and the low thermal expansion ceramic particles 4 was 80 to 85% by mass.

FIG. 5 is a diagram showing a part of a manufacturing process of the sealed structure.

FIG. 5 shows a sealing step performed after the coating / firing step of FIG.

As shown in FIG. 5, four cylindrical spacers 6 having a diameter of 500 μm × 200 μm are installed on the other glass substrate 2, and the glass substrates 1 on which the glass composite material 5 is formed are aligned so as to face each other, and the four heat-resistant clips 9 Was attached to the four sides of the glass substrates 1 and 2. Then, the lead-free glass composition 3 is heated to a temperature about 20 ° C. higher than _{the softening point T s} at a heating rate of about 5 ° C./min in the air, and held for 30 minutes to seal the glass to prepare a sealed structure. bottom. The internal space 7 of the produced sealed structure is in a slightly decompressed state due to the contraction of air.

HAST (temperature 120 ° C.-humidity 85% -pressure 2 atm) of the prepared sealing structure was carried out for 48 hours, and the moisture resistance, which is one of the reliability of the sealing portion, was evaluated.

If even a part of the sealing portion was peeled off and leaked, it was judged as a failure "x", and if it did not leak without peeling, it was judged as a pass "○".

In the case of a leak, moisture enters the inside of the sealing structure, so that it can be easily determined. The sealed structure that passed HAST was subjected to a 30-minute immersion test by a strong ultrasonic cleaning test, and the adhesiveness, which is one of the reliability of the sealed portion, was evaluated in the same manner as described above.

Similar to the above moisture resistance, if a part of the sealing part is peeled or cracked and leaks, it fails "x", and if it does not leak without peeling or cracking, it passes "○". It was judged. As for this adhesiveness evaluation method, if a leak occurs, moisture enters the inside of the sealing structure, so that it can be easily determined.

Table 3 shows the density, characteristic temperature, coefficient of thermal expansion, moisture resistance, softening fluidity and adhesiveness of Examples A-01 to A-69.

Table 4 shows the density, characteristic temperature, coefficient of thermal expansion, moisture resistance, softening fluidity, and adhesiveness of Comparative Examples B-01 to B-07.

In addition, Tables 5 to 7 show the evaluation results (moisture resistance, adhesiveness) of the sealed structure prepared by using the lead-free glass composite material containing the lead-free glass compositions of Tables 1 and 2 and the low thermal expansion ceramic particles. It is shown.

Table 5 shows Examples A-01 to A-40.

Table 6 shows Examples A-41 to A-69.

Table 7 shows Comparative Examples B-01 to B-07.

As shown in Table 2, Comparative Examples B-01 to B-06 are _{V 2} O _5- TeO _2- Fe ₂ O _3- P ₂ O ₅ series lead-free glass compositions containing no _{Li 2 O, and are Comparative Examples.} B-07 is a _{V 2} O _5- TeO _2- BaO-WO _3- P ₂ O ₅ series lead-free glass composition containing no _{Fe 2} O ₃ and Li _{2 O.}

As shown in Table 4, all of the glass compositions of Comparative Examples showed good softening fluidity, and all were judged to be acceptable “◯”.

Regarding the moisture resistance by HAST, Comparative Examples B-01 to B-04 were good and evaluated as "○", but Comparative Examples B-05 to B-07 were rejected because corrosion was observed. Was judged. _{Therefore, V 2} O _5- TeO _2- Fe _{2 which contains Fe 2} O ₃ which is effective for improving chemical stability such as moisture resistance and whose content is larger than _{that of P 2} O ₅ It _{can be seen that the O 3-} P ₂ O ₅ series lead-free glass compositions (B-01 to B-04) have excellent moisture resistance. When _{the content of Fe 2} O _{3 and} the content of P ₂ O ₅ are reversed, V ₂ O _5- TeO _2- Fe ₂ O _3- P ₂ O ₅ series lead-free glass compositions (B-05 and B-06) Even so, it can be seen that the moisture resistance due to HAST is poor.

In addition, the _{V 2} O _5- TeO _2- BaO-WO _3- P ₂ O ₅ lead-free glass composition (B-07) containing no _{Fe 2} O ₃ is more corroded than B-05 or B-06. The moisture resistance was even lower.

Regarding the adhesiveness to the soda lime glass substrate, all of the comparative examples were easily peeled off from the soda lime glass substrate, so all of them were judged to be rejected “x”.

Further, as shown in Table 7, a lead-free glass composite material containing the lead-free glass compositions of Comparative Examples B-01 to B-04 and zirconium tungrate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) ₂ ) is used. The sealed structure was airtightly sealed, and no leak was observed even in the moisture resistance of HAST, and the result was judged as “◯”. However, regarding the adhesiveness by the ultrasonic cleaning test, a leak was observed, and the result was judged as "x".

The sealing structure using the lead-free glass composite material containing the lead-free glass composition of Comparative Examples B-05 to B-07 and zirconium tungrate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) _{2) is airtight.} However, a leak was observed in the moisture resistance of HAST, and the result was judged as "x". Adhesiveness was not evaluated because leaks were found in the moisture resistance evaluation.

In contrast, Example A-01~A-69 shown in Tables 5 and 6, comprises a Li ₂ O, and, _V 2 over the content of content _P 2 _{O 5} of _Fe 2 _{O 3} O _{It was a 5-} TeO _2- Fe ₂ O _3- P ₂ O ₅ system lead-free glass composition, and all the glass compositions were excellent in moisture resistance, softening fluidity, and adhesiveness.

Further, a sealing structure using a lead-free glass composite material containing these lead-free glass compositions (A-01 to A-69) and zirconium tungrate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) _2). In the case, all the sealing structures of the examples were airtightly sealed, and in the subsequent evaluation of the moisture resistance by HAST and the adhesiveness by ultrasonic cleaning, there was no leakage, and both the moisture resistance and the adhesiveness were both. Passed "○" was judged.

From the above, Examples A-01 to A-69 contain vanadium oxide, tellurium oxide, iron oxide, phosphorus oxide and lithium oxide as main components, and the desirable content of the main components is the above relational expression (1). It can be seen that ~ (9) is satisfied.

Further, it can be seen that the densities of Examples A-01 to A-69 are 3.6 g / cm ³ or more and 4.0 g / cm ³ or less, and the softening point by differential thermal analysis is 400 ° C. or less.

Further, the lead-free glass compositions of Examples A-01 to A-69 are suitable for producing lead-free glass composite materials and lead-free glass pastes by combining with low thermal expansion ceramic particles, and the sealing produced using these is suitable. It turns out that it is suitable for the structure.

In the following examples, lead-free glass composite materials and lead-free glass pastes containing the lead-free glass composition of the present invention, and sealing structures and electrical and electronic components to which they are applied will be described in more detail.

In Example 2, a lead-free glass composite material containing a lead-free glass composition and ceramic particles or glass beads is used, and in the same manner as in Example 1, metal substrates of the same type, ceramic substrates, glass substrates, and semiconductors are used. A sealing structure was produced by sealing the outer peripheral portions of the substrates. HAST of the prepared sealed structure was carried out for 48 hours, and then an ultrasonic cleaning test was carried out for 30 minutes to evaluate the reliability of the sealed portion.

Examples of the lead-free glass composition include Examples A-06, A-12, A-14, A-25, A-33, A-41-A-43, A-53, A-62 and A shown in Table 1. 16 types of -65 to A-69 and Comparative Example B-01 shown in Table 2 were used.

Table 8 shows 10 kinds of materials (C-01 to C-10) used as ceramic particles or glass beads. The table also shows the density, coefficient of thermal expansion, and average particle size of these materials.

The metal substrate is a 50 mm x 50 mm stainless steel (SUS304) substrate with a thickness of 3 mm, the ceramic substrate is a 50 mm x 50 mm alumina (Al ₂ O ₃ ) substrate with a thickness of 1.5 mm, and the glass substrate is thick. A 50 mm × 50 mm borosilicate glass (SiO _2- B ₂ O _3- Na ₂ O-based glass) substrate having a diameter of 2 mm and a silicon substrate having a thickness of 1 mm were used as the semiconductor substrate. The coefficient of thermal expansion of each substrate is 178 × ^{10-7 / ° C for the SUS304 substrate, 81 × 10-7} / ° C for the alumina substrate, ^{58 × 10-7} / ° C for the borosilicate glass substrate, and 28 for the silicon substrate. It was × ^10-7 / ° C.

In producing the sealing structure for evaluation, first, a glass paste containing particles of the lead-free glass composition, ceramic particles or glass beads, a binder, and a solvent is produced, and the same as in Example 1. Then, it was applied to the outer peripheral portion of each substrate, dried, and fired. Then, a spacer was installed, and the base materials were combined and heated to seal the mixture.

(Making lead-free glass paste)
A lead-free glass paste was prepared in the same manner as in Example 1 except that the blending ratio of the particles of the lead-free glass composition and the particles of ceramics or glass beads was changed. The blending ratio of the particles of the lead-free glass composition and the particles of ceramics or glass beads is 100: 0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60 and 30 in% by volume. : 70 types were used. The content of the solid content (total of the lead-free glass composition and the ceramics) in the lead-free glass paste was about 80% by mass.

(Preparation and evaluation of sealed structure)
A sealed structure was prepared in the same manner as in Example 1, HAST was carried out for 48 hours, and then an ultrasonic cleaning test was carried out for 30 minutes to evaluate the reliability of the sealed portion.

After the test, the mixture was dried at 80 ° C. to break the sealing structure, and when no water remained inside, it was judged as “◯”, and when water remained, it was judged as rejected “x”.

The sealing temperature of the sealing structure was determined by the lead-free glass composition contained in the lead-free glass composite material. Similar to Example 1, the pre-baking was performed at a temperature about 30 ° C. higher than the _{softening point T s} , and the sealing was performed at a temperature about 20 ° C. higher than the _{softening point T s.} In producing the sealed structure, the types and contents of the lead-free glass composition and ceramics in the lead-free glass paste were selected in consideration of the coefficient of thermal expansion of each substrate.

Tables 9 to 12 show the HAST evaluation results of the sealed structure in each substrate.

Table 9 is a sealing structure between stainless steel (SUS304) substrates, Table 10 is a sealing structure between alumina (Al ₂ O ₃ ) substrates, and Table 11 is a borosilicate glass (SiO _2- B ₂ O ₃ −). Na ₂ O-based glass) encapsulation structures between substrates, Table 12 shows the evaluation results of encapsulation structures between silicon (Si) substrates.

In the sealing structure between stainless steel (SUS304) substrates, as shown in Table 9, C-03, C-04 and C-07 to C-10 (Table 8) are used as ceramics, and the blending ratio is 0 to 0. Examples A-14, A-53, A-65 and A-69 and Comparative Example B-01 were used as a 20% by volume lead-free glass composition, and the blending ratio thereof was examined in the range of 100 to 80% by volume.

In the sealing structure of the embodiment, a highly reliable sealing portion can be obtained without peeling and moisture invading under all conditions, and in all the examples, stainless steel (SUS304). ) It was found that the adhesive strength and adhesion to the substrate were high. However, in the sealing structure of the comparative example, peeling from the sealing interface occurred under any of the compounding conditions, and a highly reliable sealing portion could not be obtained.

In the sealing structure between alumina (Al ₂ O ₃ ) substrates, as shown in Table 10, C-01, C-02 and C-06 (Table 8) are used as ceramics, and the mixing ratio is 20 to 40 volumes. %, Examples A-06, A-12, A-25, A-33, A-41, A-43, A-66 and A-67 and Comparative Example B-01 were used as lead-free glass compositions thereof. The blending ratio was examined in the range of 80 to 60% by volume.

In the sealing structure of the examples, a highly reliable sealing portion can be obtained without peeling and without moisture entering the inside under all conditions, and in all the examples, alumina (Al _{2) can be obtained.} O ₃ ) It was found that the adhesive strength and adhesion to the substrate were high. However, in the sealing structure of the comparative example, although it did not peel off from the sealing interface under any of the compounding conditions, water intrusion was observed inside and a highly reliable sealing portion could not be obtained. rice field.

In the sealing structure between borosilicate glass (SiO _2- B ₂ O _3- Na ₂ O-based glass) substrates, as shown in Table 11, C-01, C-02 and C-05 (Table 8) are used as ceramics. ), The blending ratio thereof is 30 to 50% by volume, and the lead-free glass composition is compared with Examples A-06, A-12, A-33, A-42, A-62, A-68 and A-69. Using Example B-01, the blending ratio was examined in the range of 70 to 50% by volume.

In the sealing structure of the examples, a highly reliable sealing portion can be obtained without peeling and without moisture entering the inside under all conditions, and the borosilicate glass in all the examples. (SiO _2- B ₂ O _3- Na ₂ O-based glass) It was found that the adhesive strength and adhesion to the substrate were high. However, in the sealing structure of the comparative example, although it did not peel off from the sealing interface under any of the compounding conditions, water intrusion was observed inside and a highly reliable sealing portion could not be obtained. rice field.

In the sealing structure between silicon (Si) substrates, as shown in Table 12, C-01 and C-05 (Table 8) are used as ceramics, and the blending ratio is 50 to 70% by volume as a lead-free glass composition. Examples A-12, A-14, A-25, A-42, A-53, A-62 and A-66 to A-69 and Comparative Example B-01 are used, and the blending ratio thereof is 50 to 30 volumes. It was examined in the range of%.

In the sealing structure of the example, when the blending ratio of the lead-free glass composition and the ceramics is 50:50 and 40:60, the sealing is highly reliable without peeling and without moisture entering the inside. A stop was obtained, and the adhesive strength and adhesion to the silicon (Si) substrate were high. However, when the compounding ratio was 30:70, although the sealing interface was not peeled off, water intrusion was observed inside. It is probable that this is because the blending ratio of the lead-free glass composition was too small with respect to the blending ratio of the ceramics, so that good adhesiveness and adhesion could not be obtained. In the sealing structure of the comparative example, peeling from the sealing interface occurred under any of the compounding conditions, and a highly reliable sealing portion could not be obtained.

Based on the above, by using a lead-free glass composite material containing 40 to less than 100% by volume of the lead-free glass composition of the examples and 0 to 60% by volume of ceramic particles and glass beads, various substrates can be airtightly sealed at low temperature or at low temperature. It turned out that it can be bonded.

In this example, as the lead-free glass composition, Examples A-06, A-12, A-14, A-25, A-33, A-41-A-43, A-53, A shown in Table 1 are used. Although 16 types of −62 and A-65 to A-69 and Comparative Example B-01 shown in Table 2 have been described as representatives, it goes without saying that the same performance can be exhibited with respect to the lead-free glass compositions of other examples. stomach. When the lead-free glass composite material or its lead-free glass paste contains ceramic particles or glass beads, zirconium tungstate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) ₂ ), quartz glass (SiO ₂ ). , borosilicate glass _(SiO 2 _-B 2 _{O 3} system), soda lime glass _{(Si 2} -Na ₂ O-CaO-based), beta-eucryptite _{(Li 2 O · Al 2 O} 3 · 2SiO 2), cordierite _{(2MgO · 2Al 2 O 3 ·} 5SiO 2), zirconium silicate (ZrSiO _4), alumina _{(Al 2 O} 3), for mullite _{(3Al 2 O 3 · 2SiO 2} ) and niobium oxide _(Nb 2 _{O 5)} Although explained, the present invention is not limited to these.

In Example 3, a vacuum-insulated double glazing panel manufactured as one of the representative examples of the sealing structure by using two soda lime glass substrates and a glass composite material will be described.

FIG. 6A is a schematic plan view showing the produced vacuum-insulated double glazing panel.

As shown in this figure, the vacuum-insulated double glazing panel has a sealing portion 12 on the peripheral edge of the soda lime glass substrate 10. A plurality of spacers 13 are two-dimensionally arranged at equal intervals. An exhaust hole 14 is formed inside the sealing portion 12. A cap 15 is attached to the exhaust hole 14.

FIG. 6B is an enlarged view of the AA cross section in the vicinity of the sealing portion.

As shown in this figure, the vacuum-insulated double glazing panel has a structure in which a sealing portion 12 and a spacer 13 are sandwiched between two soda lime glass substrates 10 and 11. As a result, the space portion 16 is formed. The space portion 16 is in a vacuum state by exhausting air from the exhaust hole 14 using a vacuum pump (not shown).

The spacer 13 is installed between the soda lime glass substrates 10 and 11 to secure a space 16 in a vacuum state. In order to obtain the space portion 16 having a vacuum state, the space portion 16 is exhausted from the exhaust hole 14 formed in the soda lime glass substrate 11 in advance by using a vacuum pump. After exhausting, the cap 15 is attached to maintain the degree of vacuum of the space 16.

When applied as a window glass for building materials or a window glass for vehicles, it is desirable to use a vacuum-insulated double glazing panel in which a heat ray reflecting film 17 is formed on the inner surface of a soda lime glass substrate 10 by a vapor deposition method or the like.

The sealing portion 12 is made of the lead-free glass composite material of the example.

This vacuum-insulated double glazing panel can be applied to window glass for building materials, window glass for vehicles, doors of commercial refrigerators and freezers, and the like. The lead-free glass composite material of the example used for the sealing portion 12 contains the lead-free glass composition of the example, and has a coefficient of thermal expansion in order to match the coefficient of thermal expansion with the soda lime glass substrates 10 and 11. Small ceramic particles and glass beads are mixed.

Further, the soda lime glass substrates 10 and 11 have low thermal conductivity, and if the size is further increased, it is difficult to uniformly heat or cool the soda lime glass substrates, and the soda lime glass substrates 10 and 11 may be damaged by rapid heating or rapid cooling. Cooling needs to be done gradually. In order to produce a vacuum-insulated double glazing panel with good yield and efficiency, sealing at a low temperature is effective.

(Making lead-free glass paste)
A predetermined amount of particles of the lead-free glass composition, ceramic particles and glass beads, a binder, and a solvent were mixed and mixed to prepare a lead-free glass paste.

The particles of the lead-free glass composition have an A-24 particle size under 45 μm, and the ceramic particles and glass beads have an average particle size of about 15 μm C-01 (zincite tungsten phosphate particles) and an average particle size. C-02 (quartz glass beads) having a particle size of about 75 μm was used. In addition, polypropylene carbonate was used as the binder and carbitol acetate was used as the solvent.

The blending ratio of the particles of the lead-free glass composition A-59, the ceramic particles C-01 and the glass beads C-02 is 70:25: 5 in volume%, and the solid content (A-59, C-01 and C) thereof. A glass paste for sealing was prepared so that the content (total of -02) was about 80% by mass. In addition, a glass paste containing only particles having a solid content of A-59 was also prepared for fixing the spacer 13.

(Making a vacuum-insulated double glazing panel)
A method for manufacturing the vacuum-insulated double glazing panel of this embodiment will be described.

FIG. 7A is a schematic plan view showing a part of the method for manufacturing the vacuum-insulated double glazing panel shown in FIGS. 6A and 6B.

FIG. 7A shows a state in which the sealing glass paste 112 and the plurality of spacers 13 are formed on the soda lime glass substrate 11. The size of the soda lime glass substrate 11 is 900 × 600 × 3 mm. An exhaust hole 14 is formed in the soda lime glass substrate 11.

The sealing glass paste 112 was applied to the outer peripheral portion of the soda lime glass substrate 11 by the dispenser method. The spacer 13 was attached to the inside of the sealing glass paste 112 with the spacer fixing glass paste. Then, after drying at 150 ° C. in the air, the mixture was heated to 400 ° C. at a heating rate of 2 to 3 ° C./min in the air, held for 30 minutes, and temporarily fixed.

FIG. 7B shows a cross section taken along the line AA shown in FIG. 7A.

As shown in FIG. 7B, the height of the temporarily fixed sealing glass paste 112 is higher than that of the temporarily fixed spacer 13. This is important for airtight sealing.

The spacer 13 is a columnar stainless steel having a diameter of 500 μm and a height of 190 μm. The spacer 13 was fixed to the surface of the soda lime glass substrate 11 with the lead-free glass composition A-59. This is because the distance between the soda lime glass substrate 10 and the other soda lime glass substrate, that is, the thickness of the space portion is set to about 200 μm.

FIG. 8A is a schematic plan view showing a part of the method for manufacturing the vacuum insulated double glazing panel shown in FIGS. 6A and 6B.

FIG. 8A shows the soda lime glass substrate 10 constituting the vacuum-insulated double glazing panel of FIG. 6B. A heat ray reflecting film 17 was formed on the soda lime glass substrate 10.

FIG. 8B is a cross-sectional view taken along the line AA of FIG. 8A.

As shown in FIG. 8B, the heat ray reflecting film 17 was formed on one side of the soda lime glass substrate 10.

FIG. 9 shows a vacuum exhaust sealing step which is a part of the method for manufacturing the vacuum insulated double glazing panel shown in FIGS. 6A and 6B.

In FIG. 9, the soda lime glass substrates 10 and 11 were opposed to each other, aligned, and fixed with a plurality of heat-resistant clips (not shown). Then, it was heated and sealed while being evacuated from the exhaust hole 14. As a result, the soda lime glass substrate 10 was brought into close contact with the sealing glass paste 112, and the sealing portion and the space portion 16 were formed. A cap 15 was attached to the exhaust hole 14 after exhausting to maintain the degree of vacuum of the space portion 16.

FIG. 10 shows the temperature profile in the vacuum exhaust sealing step of FIG.

As shown in FIG. 10, the lead-free glass composition is _{heated to a temperature near the softening point T s} , here 370 ° C. near _{T s of} A-59, at a heating rate of 2 to 3 ° C./min in the atmosphere for 30 minutes. Retained. At this stage, the sealing glass paste 112 and the spacer 13 of FIG. 9 were crushed, and the two air-cooled reinforced soda lime glass substrates 10 and 11 were brought into close contact with each other. After that, while exhausting the inside of the panel with a vacuum pump, the temperature is about 20 ° C. higher than _{the softening point T s} of the lead-free glass composition at a heating rate of 2 to 3 ° C./min, here 20 ° C. higher than _{the T s of A-59.} It was heated to 395 ° C. and held for 30 minutes for sealing.

In this example, 10 vacuum-insulated double glazing panels were produced.

(Evaluation result of the produced vacuum-insulated double glazing panel)
The appearance of 10 vacuum-insulated double glazing panels produced in this example was inspected. As a result, no cracks or cracks were observed, and there was no problem in appearance. Further, the intervals between the soda lime glass substrates 10 and 11 were substantially uniform in thickness (about 200 μm) due to the plurality of spacers 13 installed inside the panel. That is, a vacuum-insulated double glazing panel having a predetermined space 16 was obtained.

Furthermore, from the helium leak test, it was confirmed that the inside of the panel was in a vacuum state and the outer periphery of the panel was hermetically sealed. The heat insulating property was also evaluated, and it was confirmed that a low thermal transmission rate (0.7 to 0.9 W / m ² · K) was achieved.

In order to confirm the reliability of the sealing portion 12, HAST of three manufactured vacuum-insulated double glazing panels was carried out for 48 hours. It was confirmed that the inside of the panels was maintained in a vacuum state without water entering the inside of all three panels. In addition, a temperature cycle test of −50 ° C. to + 100 ° C. was carried out 1500 times for another three vacuum-insulated double glazing panels. In this test as well, the inside of all three panels was kept in a vacuum state. From these facts, it was found that in the vacuum-insulated double glazing panel to which the glass composite material of the example and the glass paste thereof was applied, a sealing portion having high heat insulating properties and high reliability could be obtained.

Based on the above, the lead-free glass composite material containing the lead-free glass composition of Examples and the lead-free glass paste thereof can be effectively applied to the sealing portion of the vacuum-insulated double glazing panel, and the sealing structure is excellent in both heat insulating properties and reliability. It was confirmed that we can provide.

In this embodiment, as one of the representative examples of the sealing structure, a display in which a large number of organic light emitting diodes (OLEDs) are built in between two borosilicate glass substrates was produced.

FIG. 11A shows an example of an OLED display.

As shown in this figure, a sealing portion 12 containing the lead-free glass composite material of the embodiment is formed on the outer peripheral portion of the borosilicate glass substrate 18 constituting the OLED display. An organic light emitting diode 20 is provided inside the sealing portion 12.

FIG. 11B shows a cross section taken along the line AA of FIG. 11A.

As shown in FIG. 11B, a sealing portion 12 and an organic light emitting diode 20 are formed between the two borosilicate glass substrates 18 and 19.

(Making lead-free glass paste)
A predetermined amount of particles of the lead-free glass composition of Examples, particles of ceramics, a binder, and a solvent were mixed and mixed to prepare a glass paste.

A-31 having an average particle size of about 2 μm was used for the particles of the lead-free glass composition, and C-01 (zirconium tungate phosphate particles) having an average particle size of about 3 μm was used for the ceramic particles. In addition, polypropylene carbonate was used as the binder and carbitol acetate was used as the solvent. _{Iron tungstate (FeWO 4} ) was mixed in the ceramic particles C-01 so that the red semiconductor laser could be efficiently absorbed and heat was easily generated. The mixing ratio of A-31 and C-01 is 50:50 by volume, and low-temperature sealing is performed so that the content of the solid content (total of A-31 and C-01) is about 80% by mass. A lead-free glass paste for use was prepared.

(Manufacturing of OLED display)
The manufacturing method of the OLED display of this example is shown in FIGS. 12A-14.

FIG. 12A shows one substrate of the OLED display.

As shown in this figure, a lead-free glass paste was applied to the outer peripheral portion of the borosilicate glass substrate 18 by a screen printing method. Then, this was dried in the air at 150 ° C., heated to 400 ° C. at a heating rate of 5 ° C./min in the air, and held for 30 minutes. As a result, the sealing glass paste 112 was formed on the outer peripheral portion of the borosilicate glass substrate 18.

FIG. 12B is a cross-sectional view taken along the line AA of FIG. 12A.

The sealing glass paste 112 had a line width of about 2 mm and a firing film thickness of about 15 μm.

FIG. 13A shows the other substrate of the OLED display.

FIG. 13B is a cross-sectional view taken along the line AA of FIG. 13A.

As shown in these figures, the organic light emitting diode 20 was formed on the borosilicate glass substrate 19. Although not shown, the organic light emitting diode 20 is an aggregate of a large number of elements corresponding to the number of pixels.

FIG. 14 shows a sealing process that is a part of a method for manufacturing an organic light emitting diode.

As shown in this figure, the borosilicate glass substrate 18 on which the sealing glass paste 112 is formed and the borosilicate glass substrate 19 on which the organic light emitting diode 20 is formed are arranged so as to face each other, and the borosilicate glass substrate is placed in a vacuum. The laser 21 was irradiated from the outside of 18 toward the sealing glass paste 112. For the laser 21, a red semiconductor laser having a wavelength of 805 nm was used so that the laser wavelength was efficiently absorbed by the lead-free glass composition and the particles of the low thermal expansion ceramics in the lead-free glass composite material of the example to generate heat.

The laser 21 moves on the outer peripheral portion at a speed of 10 mm / sec, and the outer peripheral portions of the borosilicate glass substrates 18 and 19 are joined with a sealing glass paste 112 to prepare an OLED display.

In this example, five OLED displays were produced. The reason for using the laser for sealing is to prevent thermal damage to the OLED.

(Evaluation result of the manufactured OLED display)
First, a lighting test of the produced OLED display was performed. As a result, it was confirmed that the light was turned on without any problem. In addition, the adhesion and adhesiveness of the sealing portion were also good.

Next, HAST of this OLED display was carried out for 48 hours, and a lighting test was carried out in the same manner. For comparison, an OLED display sealed only with resin was also included. The line width of this resin seal was about 5 mm, and the thickness was about 15 μm.

The resin-sealed OLED display suffered significant deterioration. This is because moisture and oxygen enter the inside of the OLED display from the resin sealing portion, and the OLED deteriorates.

On the other hand, the OLED display of the example did not show any deterioration, and good test results were obtained. This is a result suggesting that good airtightness is maintained. Furthermore, as a result of evaluating the adhesion and adhesiveness of the sealed portion after HAST, no significant decrease as in the case of sealing with resin was observed, which was almost the same as before the test.

From the above, it is possible to effectively apply the lead-free glass composite material containing the lead-free glass composition of Examples and the lead-free glass paste thereof to the sealing portion of the OLED, and to provide a sealing structure excellent in high functionality including reliability. confirmed.

In this example, a crystal oscillator package was produced as one of the representative examples of the sealed structure.

(Making lead-free glass paste)
The particles of the lead-free glass composition, the particles of the ceramics, the binder, and the solvent were mixed and mixed to prepare a lead-free glass paste for forming a sealing portion. The particles of the lead-free glass composition are A-36 having an average particle size of about 3 μm, and the ceramic particles are C-01 (zirconium tungate phosphate particles) having an average particle size of about 15 μm as shown in Table 8, and a binder. Polypropylene carbonate was used as the solvent, and carbitol acetate was used as the solvent. The mixing ratio of A-36 and C-01 is 70:30 by volume, and the content of the solid content (total of A-36 and C-01) is about 80% by mass, so that it is lead-free. A glass paste was prepared.

(Making a crystal oscillator package)
FIG. 15 shows a cross section of the manufactured crystal oscillator package.

In this figure, the crystal oscillator package has a crystal oscillator 25 installed on the surface of a ceramic substrate 23 having wiring 22 via a conductive joint portion 24. The wiring 22 and the conductive joint portion 24 are electrically connected. As a result, the crystal unit 25 is electrically connected to the outside. The ceramic cap 26 is for protecting the crystal oscillator 25, and is airtightly adhered to the outer peripheral portion of the ceramic substrate 23 by the sealing portion 12.

In this example, the lead-free glass paste of the example was used for the sealing portion 12. As the ceramic substrate 23 and the ceramic cap 26, _{those made of alumina (α-Al 2} O ₃ ) were used.

A method for manufacturing a crystal oscillator package will be described.

FIG. 16 shows a method for manufacturing a crystal unit package.

First, the ceramic substrate 23 on which the wiring 22 is formed is manufactured (A). Next, the conductive joint portion 24 is formed on the wiring 22 (B). A crystal oscillator 25 is arranged in the conductive joint portion 24, and the crystal oscillator 25 and the conductive joint portion 24 are electrically connected by heating in a vacuum (C).

On the other hand, the ceramic cap 26 is prepared (D). Then, a lead-free glass paste containing the particles of the lead-free glass composition and the particles of the ceramics is applied to the outer peripheral portion of the ceramic cap 26, dried, heated in the air, and the lead-free glass composition in the lead-free glass composite material is heated. The sealing glass paste 112 is formed by softening and flowing (E).

In this example, the lead-free glass paste was applied by a screen printing method and dried in the air at about 150 ° C. This was heated to 370 ° C. in the air at a heating rate of 10 ° C./min and held for 30 minutes to form a sealing glass paste 112 on the outer peripheral portion of the ceramic cap 26.

The ceramic substrate 23 having the crystal transducer 25 and the conductive joint portion 24 produced in step C and the ceramic cap 26 (E) having the sealing glass paste 112 are combined and placed in an inert gas atmosphere or in a vacuum. By heating and applying a slight load 27, the lead-free glass composition in the sealing glass paste 112 is softened and flowed again (F).

As a result, the crystal unit package shown in FIG. 16 is obtained.

At the time of heating in the step F, care must be taken so that the conductive joint portion 24 does not peel off from the crystal oscillator 25 and the wiring 22. For that purpose, it is effective to make _{the softening point T s} of the lead-free glass composition in the sealing glass paste 112 as low as possible.

In this embodiment, the ceramic cap 26 on which the sealing glass paste 112 was formed was aligned with the ceramic substrate 23 to which the crystal oscillator 25 was connected as shown in step F, and placed on a dedicated fixed jig to apply a load. This was heated to 370 ° C. in a vacuum at a heating rate of 10 ° C./min and held for 15 minutes to seal the space formed between the ceramic cap 26 and the ceramic substrate 23.

In this example, 24 crystal oscillator packages were produced.

(Evaluation result of the manufactured crystal unit package)
First, a visual inspection of 18 crystal oscillator packages produced in this example was performed with a stereomicroscope. As a result, there was almost no deviation of the ceramic cap 26 at the time of sealing, and no devitrification, cracks, cracks, etc. due to crystallization were observed in the sealing portion 12, and no problem in appearance was observed.

Next, whether or not the conductive joint portion 24 inside the sealed ceramic cap 26 is electrically connected to the crystal oscillator 25 and the wiring 22 is determined by a continuity test from the wiring 22 on the outside of the ceramic substrate 23. It was confirmed that the crystal oscillator works in all the manufactured crystal oscillator packages. In addition, a helium leak test was carried out on the five crystal oscillator packages produced, and it was confirmed that the inside of the package was in a vacuum state and that the outer peripheral portion was airtightly sealed by the sealing portion 12.

In order to confirm the reliability of the sealing portion 12, HAST was carried out for 48 hours on the five crystal oscillator packages produced. After that, a helium leak test was carried out, and it was confirmed that the airtightness and adhesion of the sealing portion 12 were maintained in all the crystal oscillator packages subjected to HAST.

Based on the above, by applying the lead-free glass composite material containing the lead-free glass composition of Examples and the particles of ceramics and the lead-free glass paste thereof to the sealing portion, a crystal oscillator package having a small environmental load and high reliability. Was found to be obtained.

As described above, the vacuum insulated double glazing panel, the OLED display, and the crystal oscillator package have been described as typical examples of the sealing structure, but the present invention is not limited thereto, and various sealing structures are used. Applicable to.

1, 2: Glass substrate, 3: Lead-free glass composition, 4: Low thermal expansion ceramic particles, 5: Glass composite material, 6: Spacer, 7: Internal space, 8: Glass composite material paste, 9: Heat-resistant clip, 10, 11: Soda lime glass substrate, 12: Sealing part, 13: Spacer, 14: Exhaust hole, 15: Cap, 16: Space part, 17: Heat ray reflecting film, 18, 19: Borosilicate glass substrate, 20: Organic light emission Diode, 21: Laser, 22: Wiring, 23: Ceramic substrate, 24: Conductive junction, 25: Crystal transducer, 26: Ceramic cap, 27: Load.

Claims (13)

Contains vanadium oxide, tellurium oxide, iron oxide, phosphorus oxide and lithium oxide,
A lead-free low melting point glass composition that satisfies the following three relational expressions (1) to (3) in terms of oxide.
[V ₂ O ₅ ] + [Te _{O 2} ] + [Fe ₂ O ₃ ] + [P ₂ O ₅ ] + [Li ₂ O] ≧ 90… (1)
[V ₂ O ₅ ] ≧ [Te _{O 2} ] ＞ [Fe ₂ O ₃ ] ≧ [P ₂ O ₅ ] ≧ [Li ₂ O]… (2)
[TeO ₂ ] ≧ [Fe ₂ O ₃ ] + [P ₂ O ₅ ] + [Li ₂ O] ≧ 1/2 [V ₂ O ₅ ]… (3)
(In the formula, [X] represents the content of component X, and its unit is "mol%". The same shall apply hereinafter.) Contains vanadium oxide, tellurium oxide, iron oxide, phosphorus oxide and lithium oxide,
A lead-free low melting point glass composition satisfying the following four relational expressions (1), (2), (4) and (5) in terms of oxide.
[V ₂ O ₅ ] + [Te _{O 2} ] + [Fe ₂ O ₃ ] + [P ₂ O ₅ ] + [Li ₂ O] ≧ 90… (1)
[V ₂ O ₅ ] ≧ [Te _{O 2} ] ＞ [Fe ₂ O ₃ ] ≧ [P ₂ O ₅ ] ≧ [Li ₂ O]… (2)
30 ≤ [TeO ₂ ] ≤ 40 ... (4)
0.1 ≤ [Li ₂ O] ≤ 10 ... (5) Contains vanadium oxide, tellurium oxide, iron oxide, phosphorus oxide and lithium oxide,
A lead-free low melting point glass composition satisfying the following five relational expressions (1), (2) and (6) to (8) in terms of oxide.
[V ₂ O ₅ ] + [Te _{O 2} ] + [Fe ₂ O ₃ ] + [P ₂ O ₅ ] + [Li ₂ O] ≧ 90… (1)
[V ₂ O ₅ ] ≧ [Te _{O 2} ] ＞ [Fe ₂ O ₃ ] ≧ [P ₂ O ₅ ] ≧ [Li ₂ O]… (2)
33 ≤ [V ₂ O ₅ ] ≤ 42… (6)
7 ≤ [Fe ₂ O ₃ ] ≤ 16… (7)
6 ≤ [P ₂ O ₅ ] ≤ 15… (8) It further contains any one or more of alkali metal oxides other than lithium oxide, alkaline earth metal oxides, zinc oxide, molybdenum oxide and tungsten oxide.
The lead-free low melting point glass composition according to any one of claims 1 to 3 , which satisfies the following relational expression (9).
[Ln ₂ O] + [RnO] + [ZnO] + [MoO ₃ ] + [WO ₃ ] ≤ 10… (9)
(In the formula, Ln: alkali metal element other than Li, Rn: alkaline earth metal element) The density is 3.6 g / cm ³ or more and 4.0 g / cm ³ or less.
The lead-free low melting point glass composition according to any one of claims 1 to 4 , wherein the second endothermic peak temperature by differential thermal analysis is 400 ° C. or lower. The lead-free low melting point glass composition according to any one of claims 1 to 5.
Lead-free glass composites, including ceramic particles or glass beads. The content of the lead-free low melting point glass composition is 40% by volume or more and less than 100% by volume.
The lead-free glass composite material according to claim 6 , wherein the content of the ceramics is more than 0% by volume and 60% by volume or less. The ceramics include zirconium tungstate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) ₂ ), quartz glass (SiO ₂ ), borosilicate glass (SiO _2- B ₂ O ₃ series), and soda lime glass (Si). ₂ -Na ₂ O-CaO-based), beta-eucryptite _{(Li 2 O · Al 2 O} 3 · 2SiO 2), cordierite _{(2MgO · 2Al 2 O 3 ·} 5SiO 2), zirconium silicate (ZrSiO ₄₎ , alumina _{(Al 2 O} 3), mullite _{(3Al 2 O 3 · 2SiO 2} ) and any one or more of niobium oxide _(Nb 2 _{O 5),} lead-free glass composite material according to claim 6 or 7 .. The ceramics contain any one or more of zirconium tungate phosphate (Zr ₂ (WO ₄ ) (PO ₄ ) ₂ ) and quartz glass (SiO _2).
The lead-free glass composite material according to any one of claims 6 to 8 , wherein the content of the ceramics is 30% by volume or more and 60% by volume or less. A lead-free glass paste containing the lead-free glass composite material according to any one of claims 6 to 9, a binder, and a solvent. The binder contains polypropylene carbonate and contains
The lead-free glass paste according to claim 10 , wherein the solvent contains dihydrotermineto or carbitol acetate. A sealing structure comprising the lead-free glass composite material according to any one of claims 6 to 9 , and comprising a sealing portion forming at least a part of an internal space separated from the outside and the boundary between the outside and the outside. body. The sealing structure according to claim 12 , which is a vacuum-insulated double glazing panel, display panel or package device.

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