KR20080047624A - Process for melting glass and glass - Google Patents

Abstract

[PROBLEMS] To provide a process for melting glass which enables long-period and repeated melting of SnO-P2O5 glasses, which glasses are liable to corrode a melting vessel made of platinum, and which little causes the deterioration of glass with constituents of a melting vessel even if the constituents thereof penetrate into molten glass in the melting step; and glass. [MEANS FOR SOLVING PROBLEMS] A process for melting glass by melting a glass raw material batch in a melting vessel, characterized in that the melting vessel is one made of zirconium or a zirconium alloy.

Description

Glass melting method and glass {PROCESS FOR MELTING GLASS AND GLASS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melting method of glass and glass, and in particular, sealing of electronic components such as various ceramic packages and magnetic heads, sealing of various display devices, partitions of plasma display panels (PDPs), and metal doubles of thermos. A glass melting method and glass suitable for sealing a container and various optical glasses.

Encapsulation materials used in electronic components such as ceramic packages, magnetic heads, and display devices can be sealed at low temperatures so as not to adversely affect devices such as ICs and quartz crystal oscillators, and their thermal expansion coefficients must match those of the encapsulated materials. Required.

So far, various types of composite materials obtained by adding a refractory filler to PbO-B ₂ O ₃ -based glass or these glasses have been proposed as sealing materials satisfying these characteristics (see Patent Document 1, for example).

However, from the environmental point of view, it has recently been required to remove lead, which is an environmental load substance, from glass, and SnO-P ₂ O ₅ -based glass has been proposed as an alternative material for PbO-B ₂ O ₃ -based glass (for example, a patent document) 2, 3).

By the way, usually PbO-B ₂ O ₃ based glass is produced by melting a glass raw material in-flight for the excellent heat resistance and corrosion resistant platinum melt. In general, since the PbO-B ₂ O ₃ -based glass has a low melting temperature, the amount of erosion of the platinum melting vessel after melting is small, so that problems such as breakage of the melting vessel do not occur.

On the other hand, since SnO-P ₂ O ₅ -based glass is likely to erode the platinum melting vessel at the time of melting and may cause cracks in the platinum melting vessel, there is a problem that the platinum melting vessel cannot be used for a long time. have. In addition, platinum is a very expensive metal, so replacing the platinum melting vessel in a short time will result in an increase in melting cost.

From these circumstances, as described in Patent Documents 4 to 6, an expensive silica (quartz) melting container is used for melting the SnO-P ₂ O ₅ -based glass.

Patent Document 1: Japanese Patent Application Laid-Open No. 2-229738

Patent Document 2: Japanese Patent Application Laid-Open No. 11-292564

Patent Document 3: Japanese Patent Application Laid-Open No. 2001-48579

Patent Document 4: Japanese Patent No. 2628007

Patent Document 5: Japanese Patent Application Laid-Open No. 7-25567

Patent Document 6: Japanese Patent Application Laid-Open No. 9-235136

Since the silica expansion container described in patent documents 4-6 has a small thermal expansion coefficient, it is hard to match the glass and thermal expansion coefficient which remain | survives in a silica melting container after flowing out molten glass. If the coefficient of thermal expansion of both is inconsistent, the melting vessel made of silica tends to crack due to the difference in coefficient of thermal expansion, and the molten vessel cannot be used for a long time.

It is also contemplated to use an Inconel-based metal melting vessel having heat resistance as the melting vessel. However, since the Inconel-based metal contains Cr in the metal, a large amount of Cr is eluted in the glass at the time of melting to color the glass, and there is a problem that the eluted Cr destabilizes the glass.

Thus, the technical problem of the present invention is that it is possible to repeatedly melt a SnO-P ₂ O ₅ -based glass or the like, which tends to corrode the molten platinum container, over a long period of time, and at the time of melting, the components of the molten container elute into the molten glass. Even if it does, the elution component provides the glass melting method and glass which do not deteriorate glass.

The inventors of the present invention wherein in order to solve the technical problem, if, as a result, the melt vessel of repeating various experiments using a melting vessel made of zirconium or zirconium alloy, may be melted and the like corrosive SnO-P ₂ O ₅ based glass melting The present invention proposes that the eluting component does not deteriorate the glass even when the container is difficult to erode and the molten container is hardly broken, and the components of the molten container are eluted into the glass at the time of melting. That is, the melting method of the glass of this invention is a melting method of the glass which melts the combined glass raw material in a melting container, The melting container is characterized by being made of zirconium or a zirconium alloy.

Secondly, the melting method of the glass of the present invention is characterized by melting in an inert atmosphere or in a reducing atmosphere. Here, "inert atmosphere" refers to a vacuum environment (100 Torr or less), rare gas atmospheres such as N ₂ , Ar, and He, and "reducing atmosphere" means oxygen concentration of 10 vol% or less at normal pressure, and hydrogen or hydrocarbons. It refers to the atmosphere in which the reducing gas was injected.

Thirdly, the glass melting method of the present invention is characterized in that the glass contains 20 to 70 mol% of SnO as the glass composition.

Fourthly, the melting method of the glass of the present invention is characterized in that the glass contains 20 to 70% of SnO, 10 to 50% of P ₂ O ₅ , and 0 to 30% of B ₂ O ₃ as the glass composition.

Fifthly, the glass melting method of the present invention is characterized in that the zirconium has a purity of 97% by mass or more and contains one or two or more selected from the group of Hf, Fe and Cr as impurities.

Sixthly, the melting method of the glass of the present invention is characterized in that the zirconium alloy is a zirconium alloy containing zirconium and one or two or more selected from the group of Sn, Fe, Cr and Ni.

Seventhly, the melting method of the glass of the present invention is characterized in that the zirconium alloy is any one of a zirconium iron alloy, a zirconium copper alloy, and a zirconium aluminum alloy.

8thly, the glass of this invention is manufactured by the melting method of the said glass, It is characterized by the above-mentioned.

To claim 9, the glass of the present invention is characterized in that it contains ZrO ₂ in a 100 ~ 3000ppm by weight in terms of a glass composition.

10thly, the glass of the present invention contains 20 to 70% SnO, 10 to 50% P ₂ O ₅ , 0 to 30% B ₂ O _{5 in} mol% as the glass composition, and 100 to 100 ZrO ₂ in terms of mass. It is characterized by containing 3000ppm.

Eleventh, the glass of the present invention is used for sealing an electronic component or a display device.

The glass melting method of the present invention can repeatedly melt a SnO-P ₂ O ₅ -based glass or the like, which tends to corrode the melting vessel, over a long period of time, and at the time of melting, even if the components of the melting vessel are eluted into the glass, It is difficult to deteriorate.

Since the glass melting method of this invention uses zirconium and a zirconium alloy as a melting container, the heat resistance and corrosion resistance of a melting container can be ensured. The molten container made of zirconium or zirconium alloy does not deform at the melting temperature of the glass (for example, 70 to 100 ° C.) and hardly corrodes the molten container even when the highly corrosive SnO-P ₂ O ₅ based glass is melted. Has an advantage.

In addition, a molten container made of zirconium or a zirconium alloy has a property of being difficult to devitrify glass in addition to being difficult to powder, even if zirconium or the like is eluted with glass at the time of melting. Moreover, when eluting zirconium etc. actively with glass at the time of melting, the effect mentioned later can also be acquired.

Moreover, since zirconium and a zirconium alloy have outstanding malleability and workability, it is possible to manufacture melt containers of various shapes. In addition, zirconium and zirconium alloys are cheaper than platinum, and furthermore, the melting cost can be reduced.

In the melting method of the glass of this invention, it is preferable to melt in inert atmosphere or reducing atmosphere. In the melting temperature range (for example, 700 to 1000 ° C.), when the zirconium or zirconium alloy is left in the air, the surface of the zirconium or zirconium alloy is oxidized, and the toughness thereof is easily damaged. In particular, the tendency becomes remarkable when melting temperature is 900 degreeC or more. As a result, the molten vessel is likely to be stress fractured when subjected to thermal shock or during cooling of the molten vessel. When molten in an inert atmosphere or in a reducing atmosphere, zirconium and zirconium alloys are less likely to be oxidized, and thus the molten container is less likely to be broken, and the above situation can be effectively avoided.

In addition, the melting method of the glass of the present invention does not exclude the form of melting in the air. However, melting in an inert atmosphere or a reducing atmosphere can increase the service life of the melting vessel in addition to the above advantages, thereby reducing the melting cost. It may be.

In the case of SnO-containing glass, in particular, SnO-P ₂ O ₅ -based glass, melting in an inert atmosphere or in a reducing atmosphere is more preferable because an advantage of preventing oxidation of SnO can be obtained. In addition, in SnO-P ₂ O ₅ -based glass, when SnO in the glass composition is oxidized, the flowability of the glass is impaired at the time of firing. Here, if the content of SnO is less than 20%, the advantage of using a molten container made of zirconium or zirconium alloy is insufficient. On the contrary, if the content of SnO is more than 70%, the glass is liable to devitrify during melting and the Production efficiency is impaired. Therefore, content of SnO is in mol%, Preferably it is 20 to 70%, More preferably, it is 20 to 65%, More preferably, it is 30 to 60%.

In the melting method of the glass of the present invention, the zirconium has a purity of 97% by mass or more, preferably 99% by mass or more, and includes, for example, one or two or more selected from the group consisting of Hf, Fe, and Cr as impurities. Can be. It is preferable that Hf, Fe and Cr have a mass% display of 3% or less of Hf and 0.2% or less of Fe + Cr. If the zirconium has a purity of less than 97% by mass, the impurity component may be eluted at the time of melting, and the glass may be deteriorated.

In the glass melting method of the present invention, the zirconium alloy is a zircaloy (ASTM R6080 equivalent or ASTM R60804 equivalent) or zirconium iron alloy formed by adding one or two or more selected from the group of Sn, Fe, Cr, and Ni. , Zirconium copper alloy and zirconium aluminum alloy are preferable. These zirconium alloys are excellent in corrosion resistance, heat resistance and workability, and can be suitably used as a melting vessel.

As for zircaloy, the addition amount of Sn, Fe, Cr, and Ni is preferable to be 1.0-2.0% of Sn, 0.05-0.3% of Fe, 0.05-0.2% of Cr, and 0.02-0.1% of Ni by mass% display. The addition of these ingredients can prevent excessive corrosion.

In the melting method of the glass of this invention, 1-5 mm is preferable and, as for the thickness of a melting container, 2-3 mm are more preferable. In this way, cracking of a molten container can be prevented without impairing the workability of a molten container.

In the glass melting method of the present invention, in the vacuum atmosphere, the melting temperature is preferably 800 to 1400 ° C. In the case of inert atmosphere, melting temperature of 800-1100 degreeC is suitable. Moreover, when melting temperature is set to 800-1000 degreeC, glass can be melted suitably. When the melting temperature is high, the valence of Sn tends to change from divalent to tetravalent, that is, SnO is easily oxidized, and when the melting temperature is low, undissolved components of the glass raw material tend to remain after melting.

In the melting method of the glass of the present invention, by eluting zirconium from zirconium or a zirconium alloy, the ZrO ₂ content in the glass composition is 100 to 3000 ppm (preferably 200 to 2000 ppm, more preferably 300 to 1000 ppm) in terms of mass. It is desirable to. In this way, the weather resistance and moisture resistance of glass can be improved, without adversely affecting glass characteristics, such as devitrification resistance. In particular, in the case of SnO-P ₂ O ₅ -based glass, when the zirconium is eluted from the zirconium or the zirconium alloy, this eluting component acts as a reducing agent to suppress the oxidization of SnO in the glass composition. When the content of ZrO ₂ is less than 100ppm, it is difficult to improve the weather resistance or moisture resistance of the glass. When the content of ZrO ₂ is more than 3000 ppm, the softening point of the glass rises, making it difficult to seal at low temperature.

In addition, facilities directly contacting molten glass such as stirring vanes and gas pipes are usually manufactured using platinum. Therefore, if these facilities are also manufactured using zirconium or a zirconium alloy, the advantage which the said melting container has can be acquired.

Glass produced by the melt process of glass of the present invention it is preferred because of its low melting point characteristic, SnO-P ₂ O ₅ based glass is. In addition, SnO-P ₂ O ₅ type glass preferably has an _{SnO 20 ~ 70%, P 2} O 5 10 ~ 50%, B 2 O 3 0 ~ 30% in mol% as the glass composition.

The reason for limiting the glass composition of the SnO-P ₂ O ₅ based glass as described above is shown below.

SnO is a component for low melting point of glass. When the content of SnO is less than 30%, the viscosity of the glass becomes high, the sintering temperature becomes excessively high, and sealing cannot be performed at low temperature. When the content of SnO exceeds 70%, it becomes difficult to vitrify. Particularly, when the amount of SnO is large, the glass is easily devitrified at the time of firing. Therefore, when devitrification of the glass is not allowed at the time of firing, the content of SnO is preferably 60% or less. Moreover, when content of SnO is made into 40% or more, since the fluidity | liquidity of glass can be improved and airtight reliability, such as an electronic component, can be secured, it is more preferable.

P ₂ O ₅ is a glass-forming oxide and a component that stabilizes the glass, and the content thereof is 10 to 50%, preferably 15 to 45%, more preferably 20 to 35%. When the content of P ₂ O ₅ is less than 10%, the stability of glass becomes insufficient. When the content of P ₂ O ₅ is more than 50% of the moisture resistance of the glass deteriorates.

B ₂ O ₃ is an essential component, but is a glass-forming component, can be stabilized by the glass contained in the glass composition. The content of B ₂ O ₃ is 0 to 30%, preferably 2 to 15%. The content of B ₂ O ₃ is more than 30%, it is difficult to sealing at a low temperature to increase the viscosity of the glass.

In addition, SnO-P ₂ O _5- based glass according to the present invention in addition to the above components as a glass composition ZnO 0-20%, MgO 0-20%, Al ₂ O ₃ 0-10%, SiO ₂ 0-15% , La ₂ O ₃ 0-10%, R ₂ O (R ₂ O can be contained 0 to 20% of the total amount of Li ₂ O, Na ₂ O, K ₂ O and / or Cs ₂ O). The reason which limited these components to the said range is demonstrated below.

ZnO is not an essential component, but is a mesh-modified oxide, and it is preferable to contain 4% or more because of its large effect of stabilizing glass. However, when content of ZnO exceeds 20%, devitrification will tend to arise on the glass surface at the time of baking. In addition, when a sealing process is a long time (for example, 1 hour or more), since devitrification tends to occur on the glass surface specifically, in the sealing process of a PDP, it is necessary to stabilize glass more. In such a case, the content of ZnO may be 5 to 15%.

MgO is a mesh-modified oxide and has the effect of stabilizing glass. When MgO exceeds 20%, devitrification easily occurs on the glass surface during firing. It is preferable that content of MgO is 0 to 5%.

Al ₂ O ₃ is an intermediate oxide. Al ₂ O ₃ is not an essential component, but is preferably contained because it has the effect of stabilizing the glass and also has the effect of lowering the coefficient of thermal expansion. However, if it exceeds 10%, the softening temperature rises and the fluidity of the glass during firing is inhibited. In addition, when the stability, the thermal expansion coefficient, the fluidity, and the like of the glass are considered, the content of Al ₂ O ₃ is more preferably 1 to 5%.

SiO ₂ is a glass forming oxide. SiO ₂ is an essential component, but it is preferably contained because the effect of suppressing devitrification. On the other hand, if the content exceeds 15%, the softening temperature increases, and the fluidity during firing is significantly deteriorated. When considering the fluidity such as a low-melting material, the content of SiO ₂ is preferably from 0 to 10%.

Although R ₂ O is not an essential component, the sealing strength with the to-be-sealed object can be improved by containing at least 1 sort (s) of R ₂ O components in glass composition by 0.1% or more. However, when the content of R ₂ O exceeds 20%, the glass is liable to devitrification on sintering. Furthermore, when the fluidity of a substantial or full of glass at the time of firing is required, it is preferable that the content of R ₂ O to 10% or less.

In addition, the SnO-P ₂ O ₅ -based glass according to the present invention may be added with various components in addition to the above components as the glass composition. For example, for the purpose of stabilizing the glass, a total amount of WO ₃ , MoO ₃ , Nb ₂ O ₅ , TiO ₂ , CuO, MnO, R'O (R'O is the total amount of MgO, CaO, SrO and / or BaO), etc. 0 to 35%, preferably 0 to 25%. Moreover, when the total amount of these components exceeds 35%, the balance of glass composition will be lost, On the contrary, glass will become unstable and it will be easy to devitrify at the time of shaping of glass. It may also be contained in order to improve the weather resistance or moisture resistance of the glass, In ₂ O ₃ or the like.

Content of the said stabilizing component and the reason for limitation are demonstrated below.

The content of WO ₃ and Mo0 ₃ is preferably 0 to 20%, particularly 0 to 10%. If these components exceed 20%, the viscosity of glass will become high easily and it will become impossible to seal at low temperature.

The content of Nb ₂ O ₅ and TiO ₂ is preferably 0 to 15%, particularly 0 to 10%. When these components exceed 15%, the devitrification tendency of glass will become large easily.

As for content of CuO and MnO, 0-10%, respectively, especially 0-5% are preferable. When these components exceed 10%, glass will become unstable easily.

It is preferable that content of R'O is 0 to 15% in total amount, especially 0 to 5%. If R'O exceeds 15%, the glass is likely to become unstable.

In ₂ O ₃ can be used for the purpose of obtaining high weather resistance and moisture resistance. The content of In ₂ O ₃ is preferably 0 to 5%. Since the content of In ₂ O ₃ is more than 5%, In ₂ O ₃ raw material is expensive, resulting in an increase in the material cost of the glass.

From the environmental point of view, it is preferable not to substantially contain PbO in the glass composition. Here, "it does not contain PbO substantially" refers to the case where content of PbO in glass composition is 100 ppm or less.

The glass of the present invention contains 20 to 70% SnO, P ₂ O ₅ 1O to 50%, and B ₂ O ₃ 0 to 30% in mol% as the glass composition. Further, in the glass of the present invention, in terms of mass, it is particularly preferred to be preferred, and containing 300 ~ 1000ppm than that is preferred, and containing 200 ~ 100 ~ 3000ppm 2000ppm contained the ZrO ₂ in the glass composition. In this way, the weather resistance and moisture resistance of glass can be improved. When the content of ZrO ₂ is less than 1OOppm it is difficult to improve the weather resistance of the glass and moisture resistance. When the content of ZrO ₂ is more than 3000ppm, it is difficult to sealing at low temperatures. As described above, ZrO ₂ can be introduced into the glass composition by melting using a zirconium melting vessel or the like.

The glass of this invention can be manufactured suitably by the melting method of the said glass. SnO-P ₂ O ₅ based glass obtained by the melting method of the glass, or SnO-P ₂ O ₅ based glass having the glass composition has a glass transition point of 270 ~ 380 ℃, temperature range of about 400 ~ 60 ℃ It is a glass of low melting | fusing point which shows the favorable fluidity at. In addition, these SnO-P ₂ O ₅ based glass has a thermal expansion coefficient of about 90 ~ 150 × 10 ^-7 / ℃ in the temperature range of 30 ~ 250 ℃.

SnO-P ₂ O ₅ -based glass having such characteristics can be used as a sealing material alone as a glass powder, when the substance to be sealed and the coefficient of thermal expansion are suitable.

On the other hand, when the encapsulated material and the coefficient of thermal expansion do not match, for example, alumina (7Ox10 ^-7 / 占 폚), high strain point glass (85x10 ^-7 / 占 폚), and soda plate glass (9Ox10 ^-7 / 占 폚) when the sealing or the like is subjected to a refractory filler powder in a SnO-P ₂ O ₅ based glass powder may be a composite material. It is important to design the thermal expansion coefficient of the composite material as low as 5 ~ 30 × 10 ^-7 / ℃ for the encapsulated material. In this way, the stress applied to the sealing layer can be placed on the compression (compression) side to prevent the breaking of the sealing layer. In this case, it is good to prepare so that it may become 45 to 95 volume% of glass powder, and 5 to 55 volume% of fire-resistant filler powder.

In particular, when sealing a fluorescent display tube (VFD), a field emission display (FED), a PDP, and a cathode ray tube (CRT), it is desirable to adjust the thermal expansion coefficient of the sealing material to be about 60 to 100 × 10 ^-7 / ° C. desirable.

As a refractory filler, various refractory filler powders, such as a willemite type ceramic, (beta) -eucryptite, a zinc titanate type ceramic, cordierite, a tin oxide solid solution, a zircon type ceramic, a mullite, quartz glass, and alumina, may be added. In addition to the adjustment of the coefficient of thermal expansion, a refractory filler powder may be added, for example, in order to improve mechanical strength. In addition, from the environmental point of view, the refractory filler powder is preferably substantially free of PbO.

Example

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail based on an Example.

Tables 1 and 2 show Examples (Nos. 1 to 9) of the present invention, and Table 3 shows Comparative Examples (Nos. 10 to 12).

Glass raw materials were manufactured by combining various oxides, carbonate raw materials, and the like so as to form the glass in the table. This glass raw material was thrown into the melting container shown in the table, and it melt | dissolved in the melting atmosphere of the table at the melting temperature in the table for 2 hours.

Subsequently, the molten glass in the molten container flowed out between a pair of rotary rollers, and the film sample was produced, quenching a molten glass with a rotary roller. The formed film-like glass was ground by a ball mill, and then passed through a sieve having a mesh size of 105 µm to obtain a glass powder having an average particle diameter of about 10 µm. Moreover, the molten glass in a melting container was made to flow out into the carbon mold, and the plate-shaped glass sample was produced.

The glass transition point was determined by differential thermal analysis (DTA), and the coefficient of thermal expansion was determined by a push-type thermal expansion measurement (TMA) device.

Flow diameter was evaluated by the following flow-button test. First, the formed film-like glass was ground by a ball mill, and then passed through a sieve having a mesh size of 105 µm to obtain a glass powder having an average particle diameter of about 10 µm. Next, the powder of the mass corresponded to the true specific gravity of the obtained glass powder was weighed, this was pressed into the button shape of (phi) 20mm using the metal mold | die, and the button-shaped powder compact was obtained. Subsequently, after loading this powder compact on the window glass, it baked in the atmosphere of the table | surface. As baking conditions, after heating up at the rate of 10 degree-C / min at 450 degreeC which is a baking temperature, it hold | maintained at 450 degreeC for 10 minutes, and then it cooled down to room temperature at 10 degree-C / min. Finally, the diameter of the button after firing was measured by digital caliper. It is preferable that the diameter of this button is 20 mm or more when using it for sealing materials.

After the flow of the molten glass out of the molten container, the melted container was left to stand at room temperature, and visually determined whether or not cracks occurred in the molten container. The case where there was no crack was made into "(circle)" and the case where there was a crack was made into "x".

"Content of ZrO ₂ in glass" was measured by fluorescence X-ray analysis. In addition, the numerical value in a table | surface is a numerical value of mass conversion.

As apparent from Tables 1 and 2, Examples No. 1 to 9 had no damage to the melting vessel, the flow diameter in the flow button test was also 20 mm or more, and the obtained glass characteristics were also good. Further, the content of ZrO ₂ is also 700 ~ 1900ppm.

On the other hand, as is apparent from Table 3, in Comparative Examples No. 10 and 12, cracks occurred in the molten container, and in Comparative Example No. 11, the molten glass was strongly colored green, and the powder glass was also devitrified, so that the flow diameter was 18 mm. The glass properties were impaired because it did not flow into the furnace.

As described above, the glass melting method and the glass of the present invention include sealing of electronic components such as various ceramic packages, magnetic heads, sealing of various display devices, barrier ribs of PDP, sealing of metal double containers of thermos, and various optical glasses. Suitable for

Claims (11)

In the melting method of the glass which melts the combined glass raw material in a melting container: And the melting vessel is made of zirconium or zirconium alloy. The melting method of glass according to claim 1, wherein the glass is melted in an inert atmosphere or in a reducing atmosphere. The glass melting method according to claim 1 or 2, wherein the glass contains 20 to 70% of SnO in mol% as a glass composition. The glass composition according to any one of claims 1 to 3, wherein the glass contains 20 to 70% SnO, 10 to 50% P ₂ O ₅ , and 0 to 30% B ₂ O _{3 in} mol%. Melting method of glass to be used. The glass according to any one of claims 1 to 4, wherein the zirconium has a purity of 97% by mass or more, and contains one or two or more selected from the group of Hf, Fe, and Cr as impurities. Melting method. The glass according to any one of claims 1 to 4, wherein the zirconium alloy is a zirconium alloy containing zirconium and one or two or more selected from the group of Sn, Fe, Cr, and Ni. Melting method. The method for melting glass according to any one of claims 1 to 4, wherein the zirconium alloy is any one of zirconium iron alloy, zirconium copper alloy and zirconium aluminum alloy. It is produced by the melting method of the glass in any one of Claims 1-7, The glass characterized by the above-mentioned. The glass according to claim 8, wherein the glass contains 100 to 3000 ppm of ZrO ₂ in terms of mass as a glass composition. Glass composition comprising 20% to 70% SnO, 10% to 50% P ₂ O ₅ , 0% to 30% B ₂ O ₃ , and 100% to 3000ppm ZrO ₂ in terms of mass. . The glass according to any one of claims 8 to 10, which is used for sealing an electronic component or a display device.