JP2012072040A - Glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide glass which has excellent water resistance, is less liable to crystalize even in sealing or subsequent heat treatment, achieves a low sealing temperature and a desired expansion coefficient, and is suitable for sealing or the like with a Tg of 450°C or lower, without containing oxides of Pb, Ge, Ga, etc., or a halogen component such as fluorine, or without containing oxides of Sn and Cu in large quantities.SOLUTION: The glass contains, indicated by mol% based on oxides, 30-55% PO, 10-40% ZnO, 0.01-30% AlOand 0-30% RO (R is one or more selected from among Li, Na, K and Cs), wherein the ratio of AlO/POindicated by mol% based on oxides is 0.01-1.

Description

  The present invention relates to a glass composition applicable to sealing of various parts such as a solar power generation device, a semiconductor light emitting element, MEMS, an IC ceramic package, a crystal resonator, and an image display device.

The glassy sealing material for sealing, bonding or coating electronic parts and glass parts (hereinafter referred to as “sealing etc.”) is good for maintaining airtightness after sealing etc. Chemical durability is required. In addition, when performing operations such as sealing, the glassy sealing material must be heated to a temperature at which the glassy sealing material sufficiently softens and flows, i.e., the sealing temperature. It is desired that the sealing temperature of the sealing material is lower so as not to damage the circuit of the electronic component, the substrate, and the like due to heat. Furthermore, in order to give a strong adhesive force, the adhesive material has a high adhesive strength between the material constituting the parts to be sealed and the like, and the thermal expansion coefficient (α ) Must be as close as possible. Since sealing parts such as substrates and display panels used for various electronic components often have a smaller coefficient of thermal expansion than general glass, glass as a sealing material is less than general glass. It is required to reduce the thermal expansion coefficient.
Further, recently, due to a request for process design, the heat treatment process for sealing may be performed several times or in multiple stages by changing temperature and time. In this case, the sealing glass may be crystallized (devitrified) in the subsequent heat treatment, which may cause a problem that the sealing is not completely performed. For this reason, it is required that it is difficult to crystallize.

By the way, reducing the thermal expansion coefficient of glass means strengthening the bonding at the atomic level of the glass. If the bonding becomes strong, the sealing temperature of the glass rises, and the sealing of the sealing material described above is increased. This is contrary to lowering the deposition temperature. Therefore, it has been difficult to seal a material having a low thermal expansion coefficient at a low temperature by vitreous sealing material. In order to overcome this difficulty and satisfy the above requirements, various low-temperature softened glasses, that is, glasses having a low glass transition point (Tg) have been developed as sealing materials. In particular, a sealing material using a PbO—B ₂ O ₃ -based low-melting glass has been widely used for sealing a display panel and a CRT panel and a funnel. However, since lead is a component that has an unfavorable impact on the environment, the manufacture of glass containing PbO components and waste treatment require water quality inspection of wastewater, waste separation treatment, etc. Since a high cost is required for the countermeasure, a sealing material containing no lead is desired.

Patent Document 1 discloses P—Sn—O—F-based glass. However, low-melting glass containing a large amount of tin and copper needs to be manufactured in a reducing atmosphere, which increases the manufacturing cost. In addition, since the valence is likely to change during heating, it reacts with surrounding metals and oxygen during the sealing operation, resulting in crystallization and the like, which is a factor that prevents a precise sealing. In particular, it is not suitable for sealing in which heat treatment is performed in multiple stages.
Furthermore, halogen elements such as fluorine are highly volatile and harmful, which is undesirable for the environment. Also at the time of sealing, the physical properties of the sealing material change due to the composition variation due to the volatilization of the halogen element, which causes deterioration and corrosion of surrounding metals.

Contained in the Patent Document 2, as a low melting glass containing no _lead, TeO ₂ -GeO 2 _-B 2 is _{O 3} based glass is disclosed, the glass, TeO ₂ is less than 40% by mole% notation In addition, GeO ₂ and Ga ₂ O ₃ are contained although they are trace components. These components are not suitable for production because of high unit prices.

JP 2001-48574 A JP 2007-96257 A

  The object of the present invention is to have excellent water resistance without containing an oxide such as Pb, Ge or Ga, or a halogen component such as fluorine, or a large amount of an oxide of Sn or Cu. Alternatively, a glass suitable for sealing or the like having a Tg of 450 ° C. or less, which is difficult to crystallize in the subsequent heat treatment, can realize a low sealing temperature and a desired expansion coefficient, and the like.

As a result of intensive studies in view of the above problems, the present inventor has found that a specific amount of R ₂ O component (provided that R is selected from Li, Na, K, and Cs) in the P ₂ O ₃ —ZnO-based composition. A glass that solves the above problems by introducing a ratio of Al ₂ O 3 / P ₂ O ₅ expressed by mol% based on oxides to 0.01 or more and 1 or less. As a result, the present invention has been completed, and its specific configuration is as follows.

(Configuration 1)
In mol% display based on oxide,
30% to 55% of _P 2 _O 5,
10% to 40% ZnO,
Of _{0.01% ~30% Al 2 O 3} ,
0% to 30% R ₂ O (where R is one or more selected from Li, Na, K, Cs)
A glass having a ratio of Al ₂ O ₃ / P ₂ O ₅ expressed by mol% based on an oxide of 0.01 to 1 inclusive.
(Configuration 2)
In mol% display based on oxide,
0-15% SiO ₂ and / or
0% to 30% of _Al 2 _{O 3} and / or,
0-30% B ₂ O ₃ and / or
0-20% MgO and / or
0-20% CaO and / or
0-20% SrO and / or
0-20% BaO and / or
0-30% ZrO ₂ and / or
0-30% TiO ₂
The glass of the structure 1 containing each component of.
(Configuration 3)
In mol% display based on oxide,
0-20% Bi ₂ O ₃ and / or
0-20% TeO ₂ and / or
0-20% CuO and / or
From 0% to 5% of _La 2 _{O 3} and / or,
0% to 5% Y ₂ O ₃ and / or
From 0% to 5% of _Gd 2 _{O 3} and / or,
0% to 10% WO ₃ and / or
0-10% MoO ₃ and / or
0% to 5% Nb ₂ O ₅
The glass of the structure 1 or 2 containing each component of these.
(Configuration 4)
Tg is 450 ° C. or lower, a crystallization temperature is 500 ° C. or higher, and a weight loss ratio after immersion in boiling water for 60 minutes is smaller than 0.60 wt%. Glass.
(Configuration 5)
The glass according to any one of Structures 1 to 4, wherein an average linear thermal expansion coefficient is 150 × 10 ⁻⁷ / ° C. or less at 30 ° C. to 250 ° C.

  According to the present invention, it is possible to solve the above problems without containing an oxide such as Pb, Ge, or Ga, or a halogen component such as fluorine, or without containing a large amount of an oxide of Sn or Cu. In particular, the following effects can be obtained.

  According to the present invention, a glass having a Tg of 450 ° C. or lower can be obtained.

The glass of the present invention has an average linear expansion coefficient at 30 ° C. to 250 ° C. of 150 × 10 ⁻⁷ / ° C. or less, and has a thermal expansion coefficient close to that of carbon steel, stainless steel (SUS410), and hard glass, so an alloy It is suitable for sealing each other or alloy and glass.

  The crystallization temperature of the glass of the present invention is 500 ° C. or higher, and it is difficult to crystallize during sealing or in a subsequent heat treatment step.

  Further, according to the present invention, it is possible to obtain a glass having excellent water resistance and having a weight loss rate of less than 0.60 wt% after being immersed in boiling water for 60 minutes.

  The above test is performed as follows. The glass to be measured is crushed in an iron mortar to a particle size of 425 to 600 μm, and a gram amount 3 to 4 times the specific gravity is collected. Remove the iron powder mixed in the collected glass powder with a magnet, transfer the glass powder into a 50 ml beaker, add methyl alcohol to a total volume of about 30 ml, and stir with a glass rod. Remove. After repeating this washing 5 times, it is filtered with a glass filter (1G filter) using a suction filtration pump. The glass powder in the filter is dried for 60 minutes in a dryer (110 to 120 ° C.) and then allowed to cool in a silica gel desiccator. After accurately weighing the weight of the dried glass sample, place it in a specific gravity bottle and place it in a platinum basket. A platinum basket is placed in a quartz glass round bottom flask containing pure water (pH 6.5-7.5) and treated in a boiling water bath for 60 minutes. After the treatment, the platinum basket is transferred to a beaker containing methyl alcohol and washed. After washing, put in a weighing bottle and dry for 60 minutes in a dryer (110-120 ° C). After drying, the mixture is allowed to cool for 60 minutes with a silica gel desiccator, and then the mass is measured.

It is a measurement result of DTA of Example 5.

The present invention will be described.
In the present specification, “expressed in mol% based on oxide” means that oxides, composite salts, metal fluorides, etc. used as raw materials for the glass constituents of the present invention are all decomposed into an oxide during melting. It is a method of describing each component contained in the glass by the mol% of the generated oxide, assuming that it changes.

The P ₂ O ₅ component is a component that forms a glass skeleton and is an essential component. If the content of the P ₂ O ₅ component is less than 30%, vitrification is difficult, and crystallization becomes easier by heating at the time of sealing. In order to overcome this problem, the content of the P ₂ O ₅ component is preferably 30% or more, more preferably 33% or more, and most preferably 35% or more.
When the content of the P ₂ O ₅ component exceeds 55%, the chemical durability is deteriorated and the viscosity is increased, so that sealing at a low temperature becomes difficult. In order to overcome this problem, the content of the P ₂ O ₅ component is preferably 55%, more preferably 50% or less, and most preferably 43% or less.

The Al ₂ O ₃ component can form a glass skeleton, improves chemical durability, is an effective component for stabilizing glass, and is an essential component. If the ratio of the content of Al ₂ O ₃ and the component to P ₂ O ₅ expressed in mol% on the basis of oxide (hereinafter referred to as “Al ₂ O ₃ / P ₂ O ₅ ratio”) is less than 0.01, the chemical For example, when used in a paste form, the glass component is eluted in the solvent and cannot be sealed. Furthermore, it becomes a factor which reacts with the surrounding substance and deteriorates after sealing. Therefore, in order to overcome this problem, the Al ₂ O ₃ / P ₂ O ₅ ratio is preferably 0.01 or more, more preferably 0.02 or more, and most preferably 0.05 or more.
When the Al ₂ O ₃ / P ₂ O ₅ ratio is more than 1, vitrification becomes difficult and the viscosity becomes remarkably high, Tg (glass transition point) becomes high, and the working temperature at the time of sealing becomes high. The lower the Al ₂ O ₃ / P ₂ O ₅ ratio is, the lower the sealing temperature and the more industrially effective, but at the same time the chemical durability is deteriorated, so it is preferably 1 or less, more preferably 0.5 or less, and most preferably 0.3 or less.

Al ₂ O ₃ viscosity with glass and the content of the component is greater than 30% resulting in devitrification increases. Therefore, in order to overcome this problem, the content of the Al ₂ O ₃ component is preferably 30% or less, more preferably 20% or less, and most preferably 12% or less. On the other hand, when the content of the Al ₂ O ₃ component is less than 0.01%, the glass skeleton becomes unstable, and elution of the glass component and deterioration of chemical durability become remarkable. In order to overcome this problem, the content of the Al ₂ O ₃ component is preferably 0.01% or more, more preferably 1% or more, and most preferably 2.5% or more.

  The ZnO component is a component having an effect of improving meltability and chemical durability, and is an essential component. However, if the content is more than 40%, the glass tends to devitrify. Therefore, the content of the ZnO component is preferably 40% or less, more preferably 37% or less, and most preferably 34% or less. On the other hand, when the content of the ZnO component is less than 10%, it is difficult to vitrify, the viscosity and Tg are increased, and the sealing temperature is increased. Furthermore, when sealing, it crystallizes and it becomes impossible to perform airtight sealing. In order to overcome this problem, the content of the ZnO component is preferably 10% or more, more preferably 20% or more, and most preferably 25% or more.

The R ₂ O component (where R is one or more selected from Li, Na, K, and Cs) is a component that improves meltability and lowers Tg, and can be optionally contained. However, when the total amount of these components is more than 30%, the chemical durability is remarkably deteriorated, and crystallization is easily caused by heat treatment at the time of sealing. Therefore, in order to overcome this problem, the total amount of these components is preferably 30% or less, more preferably 27% or less, and most preferably 25% or less.

Li 2 _O component improves the meltability is a component to lower the Tg, is a component that may be present in any. However, when the content is more than 30%, the chemical durability is remarkably deteriorated, and it is easy to crystallize by heat treatment at the time of sealing. Therefore, in order to overcome this problem, the content is preferably 30% or less, more preferably 25% or less, and most preferably 15% or less.
As described above, the Li ₂ O component is a component that improves the meltability and lowers the Tg, but is a component that easily dissolves and deteriorates the chemical durability. Therefore, it is better to mix with components having a large ion radius such as K and Ba to suppress elution of the Li ₂ O component (mixed alkali effect). Therefore, the ratio of the content of Li ₂ O to the content of K ₂ O or / and BaO, (referred to as “Li ₂ O / (K ₂ O + BaO) ratio}” is preferably 30 or less, more preferably 10 or less. And most preferably 5 or less.

Na 2 _O component improves the meltability is a component to lower the Tg, is a component that may be present in any. However, when the content is more than 30%, the chemical durability is remarkably deteriorated, and it is easy to crystallize by heat treatment at the time of sealing. Therefore, in order to overcome this problem, the content is preferably 30% or less, more preferably 25% or less, and most preferably 15% or less.

K 2 _O component improves the meltability is a component to lower the Tg, is a component that may be present in any. However, when the content is more than 30%, the chemical durability is remarkably deteriorated, and it is easy to crystallize by heat treatment at the time of sealing. Therefore, in order to overcome this problem, the content is preferably 30% or less, more preferably 25% or less, and most preferably 15% or less.

Cs 2 _O component improves the meltability is a component to lower the Tg, is a component that may be present in any. However, when the content is more than 30%, the chemical durability is remarkably deteriorated, and it is easy to crystallize by heat treatment at the time of sealing. Therefore, in order to overcome this problem, the content is preferably 30% or less, more preferably 25% or less, and most preferably 15% or less.

The SiO ₂ component is a component capable of forming a glass skeleton, and is a component that stabilizes the glass and improves the chemical durability. Therefore, it is an optional component, but is preferably contained.
When the content of the SiO ₂ component is more than 15%, the glass is phase-divided to devitrify and increase in viscosity. Therefore, the content of the SiO ₂ component is preferably 15% or less, more preferably 10% or less, and most preferably 6% or less.

The B ₂ O ₃ component is a component that can form a glass skeleton in the same manner as the SiO ₂ component, and can be optionally contained because it has the effect of improving the meltability and stabilizing the glass. However, when the content of this component exceeds 30%, chemical durability is deteriorated and devitrification easily occurs. Therefore, the upper limit of the content of the B ₂ O ₃ component is preferably 30% or less, more preferably 15% or less, and most preferably 6% or less.

The SiO ₂ component and the B ₂ O ₃ component are components that can form a glass skeleton as described above, and are components that can be optionally contained because they are components that stabilize glass and improve chemical durability.
However, when the total content of these components (SiO ₂ + B ₂ O ₃ ) exceeds 30%, phase separation occurs and the glass tends to devitrify. Therefore, the total content of these components is preferably 30% or less, more preferably 15% or less, and most preferably 5% or less.

  The MgO component is a component that stabilizes the glass and improves the meltability, and can be optionally contained. However, when the content is more than 20%, the chemical durability is deteriorated and the glass is easily devitrified. Therefore, the content of the MgO component is preferably 20% or less, more preferably 12% or less, and most preferably 8% or less.

  The CaO component is a component that stabilizes the glass, improves the meltability, and improves the durability, and can be optionally contained. However, when the content is more than 20%, the chemical durability is deteriorated and the glass is easily devitrified. Therefore, the content of the CaO component is preferably 20% or less, more preferably 12% or less, and most preferably 8% or less.

  The SrO component is a component that stabilizes the glass and improves the meltability, and can be optionally contained. However, when the content is more than 20%, the chemical durability is deteriorated and the glass is easily devitrified. Therefore, the content of the SrO component is preferably 20% or less, more preferably 12% or less, and most preferably 8% or less.

  The BaO component is a component that stabilizes the glass and improves the meltability, and can be optionally contained. However, when the content is more than 20%, the chemical durability is deteriorated and the glass is easily devitrified. Therefore, the content of the BaO component is preferably 20% or less, more preferably 12% or less, and most preferably 8% or less.

The TiO ₂ component is a component that improves durability and can be optionally contained. However, if the content is more than 30%, the glass tends to devitrify. Therefore, the content of the TiO ₂ component is preferably 30% or less, more preferably 22% or less, and most preferably 15% or less.

The ZrO ₂ component is a component that improves durability and can be optionally contained. However, if the content is more than 30%, the glass is remarkably easily devitrified. Therefore, the content of the ZrO ₂ component is preferably 30% or less, more preferably 22% or less, and most preferably 10% or less.

The Bi ₂ O ₃ component is a component that stabilizes the glass and improves the meltability, and can be optionally contained. However, when the content is more than 20%, the chemical durability is deteriorated and the glass is easily devitrified. Therefore, the content of the Bi ₂ O ₃ component is preferably 20% or less, more preferably 12% or less, and most preferably 8% or less.

The TeO ₂ component is a component that stabilizes the glass and improves the meltability, and can be optionally contained. However, when the content is more than 20%, the chemical durability is deteriorated and the glass is easily devitrified. Therefore, the content of the TeO ₂ component is preferably 20% or less, more preferably 12% or less, and most preferably 8% or less.

  The CuO component is a component that stabilizes the glass and improves the meltability, and can be optionally contained. However, when the content is more than 20%, the chemical durability is deteriorated and the glass is easily devitrified. Therefore, the content of the CuO component is preferably 20% or less, more preferably 12% or less, and most preferably 8% or less.

The La ₂ O ₃ component is a component that improves durability and can be optionally contained. However, if the content is more than 5%, the glass is remarkably easily devitrified. Therefore, the content of La ₂ O ₃ component is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less.

The Y ₂ O ₃ component is a component that improves durability and can be optionally contained. However, if the content is more than 5%, the glass is remarkably easily devitrified. Therefore, the content of the Y ₂ O ₃ component is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less.

The Gd ₂ O ₃ component is a component that improves durability and can be optionally contained. However, if the content is more than 5%, the glass is remarkably easily devitrified. Therefore, the content of the Gd ₂ O ₃ component is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less.

The WO ₃ component is a component that improves the meltability, and can be optionally contained. However, if the content is more than 10%, the glass is remarkably easily devitrified. Therefore, the content of the WO ₃ component is preferably 10% or less, more preferably 8% or less, and most preferably 5% or less.

The MoO ₃ component is a component that improves the meltability, and can be optionally contained. However, if the content is more than 10%, the glass is remarkably easily devitrified. Therefore, the content of the MoO ₃ component is preferably 10% or less, more preferably 8% or less, and most preferably 5% or less.

The Nb ₂ O ₅ component is a component that improves durability and can be optionally contained. However, if the content is more than 5%, the glass is remarkably easily devitrified. Therefore, the content of the Nb ₂ O ₅ component is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less.

  The SnO component is a component that stabilizes the glass and improves the meltability, and can be optionally contained. However, when the content is more than 20%, the chemical durability is deteriorated and the glass is easily devitrified. Therefore, the SnO component content is preferably 20% or less, more preferably 12% or less, and most preferably 8% or less.

  Glass having a Tg exceeding 450 ° C. has a high sealing temperature and causes damage to electronic components and the like. Therefore, Tg is preferably 450 ° C. or lower, more preferably 420 ° C. or lower, and most preferably 400 ° C. or lower.

  When the crystallization temperature (Tx) is lower than 500 ° C., crystallization occurs during the sealing operation, and airtight sealing cannot be performed. Therefore, Tx is preferably 500 or more, more preferably 550 ° C. or more, and most preferably 600 ° C. or more.

  When the mass loss rate after immersion in boiling water for 60 minutes is 0.60 wt% or more, for example, when it is made into a paste, the glass is eluted and cannot be sealed. Moreover, it deteriorates by reacting with surrounding substances after sealing or reacting with water vapor in the air. Therefore, the amount of mass change after immersion in boiling water for 60 minutes is preferably smaller than 0.60 wt%, more preferably smaller than 0.25 wt%, and most preferably smaller than 0.1 wt%.

When the average linear thermal expansion coefficient exceeds 150 × 10 ⁻⁷ / ° C. at 30 ° C. to 250 ° C., the difference in thermal expansion between the carbon steel and the hard glass becomes large, which is a factor that cannot be broken or hermetically sealed. Therefore, when the average linear thermal expansion coefficient is 30 ° C. to 250 ° C., 150 × 10 ⁻⁷ / ° C. or less is preferable, 140 × 10 ⁻⁷ / ° C. or less is more preferable, and 130 × 10 ⁻⁷ / ° C. or less is most preferable.

  Hereinafter, the glass according to the present invention will be described with specific examples.

[Production of glass]
Silica sand, boric acid, dibasic ammonium phosphate, aluminum oxide, aluminum metaphosphate, lithium carbonate, sodium carbonate, no. 2 so that the glass has a composition ratio shown in Tables 1 and 2 expressed in mol% based on oxide. Sodium monophosphate, potassium carbonate, potassium dihydrogen phosphate, zinc oxide, zinc metaphosphate, magnesium oxide, calcium oxide, strontium carbonate, strontium nitrate, barium carbonate, barium nitrate, barium metaphosphate, titanium oxide, zirconium oxide, dioxide dioxide Glass raw material batches such as tellurium, copper oxide, bismuth oxide, tungsten oxide, tin oxide, lanthanum oxide, iron oxide, yttrium oxide, gadolinium oxide, molybdenum oxide, niobium oxide, arsenous acid, and antimony pentoxide were prepared. The glass raw material batch was filled into an alumina crucible, a quartz crucible, or a platinum crucible, and heated and melted at a temperature of 1000 ° C. to 1400 ° C. for 1 to 4 hours in an electric furnace. The molten glass was molded into a plate shape and slowly cooled.

[Measurement of glass]
For the prepared glass, glass transition point (Tg), crystallization temperature (Tx), average linear thermal expansion coefficient at 30 ° C. to 250 ° C., chemical durability (water resistance and acid resistance) and viscosity of glass are measured. It was. The results are shown in Tables 1-3.

(Glass transition point)
The glass transition point (Tg) and the crystallization temperature (Tx) were measured with a differential thermal analyzer (DTA) at a heating rate of 10 ° C./min. A sample in which a crystallization peak was not clearly observed was marked with “-” and evaluated as a glass that was difficult to crystallize.

(Coefficient of thermal expansion)
According to JOGIS (Japan Optical Glass Industry Association Standard) 16-2003 “Measurement Method of Average Linear Expansion Coefficient of Optical Glass Near Room Temperature”, the temperature range was changed from 30 ° C. to 250 ° C. The coefficient was measured. The measured average linear expansion coefficient (α) values are shown in Tables 1-3.

(Chemical durability)
The chemical durability (water resistance and acid resistance) was measured according to the Japan Optical Glass Industry Association Standard “Method for Measuring Chemical Durability of Optical Glass” JOGIS06-1999.

(Measurement of water resistance)
The glass is crushed in an iron mortar to a particle size of 425 to 600 μm, and a gram amount 3 to 4 times the specific gravity is collected. Remove the iron powder mixed in the collected glass powder with a magnet, transfer the glass powder into a 50 ml beaker, add methyl alcohol to a total volume of about 30 ml, and stir with a glass rod. Remove. After repeating this washing 5 times, it is filtered with a glass filter (1G filter) using a suction filtration pump. The glass powder in the filtration period is dried for 60 minutes in a dryer (110 to 120 ° C.) and then allowed to cool in a silica gel desiccator. After accurately weighing the weight of the dried glass sample, place it in a specific gravity bottle and place it in a platinum basket. The platinum basket was placed in a quartz glass round bottom flask containing pure water (pH 6.5-7.5) and treated in a boiling water bath for 60 minutes. After the treatment, the platinum basket is transferred to a beaker containing methyl alcohol and washed. After washing, put in a weighing bottle and dry for 60 minutes in a dryer (110-120 ° C). After drying, after cooling for 60 minutes with a silica gel desiccator, measure the mass, calculate the weight loss rate (wt%) of the glass sample, and if the weight loss rate (wt%) is less than 0.05, class 1, weight loss Class 2 when the rate is 0.05 to less than 0.10, Class 3 when the rate of weight loss is less than 0.10 to 0.25, Class 4 when the rate of weight loss is less than 0.25 to 0.60, The case where the weight loss rate is 0.60 to less than 1.10 is class 5, and the case where the weight loss rate is 1.10 or more is class 6. The smaller the number of classes, the better the water resistance of the glass. Means that.

(Measurement of acid resistance)
The glass is crushed in an iron mortar to a particle size of 425 to 600 μm, and a gram amount 3 to 4 times the specific gravity is collected. Remove the iron powder mixed in the collected glass powder with a magnet, transfer the glass powder into a 50 ml beaker, add methyl alcohol to a total volume of about 30 ml, and stir with a glass rod. Remove. After repeating this washing 5 times, it is filtered with a glass filter (1G filter) using a suction filtration pump. The glass powder in the filtration period is dried for 60 minutes in a dryer (110 to 120 ° C.) and then allowed to cool in a silica gel desiccator. After accurately weighing the weight of the dried glass sample, place it in a specific gravity bottle and place it in a platinum basket. The platinum basket was placed in a quartz glass round bottom flask containing a 0.01N aqueous nitric acid solution and treated in a boiling liquid bath for 60 minutes. After the treatment, the platinum basket is transferred to a beaker containing methyl alcohol and washed. After washing, put in a weighing bottle and dry for 60 minutes in a dryer (110-120 ° C). After drying, after cooling for 60 minutes with a silica gel desiccator, measure the mass, calculate the weight loss rate (wt%) of the glass sample, class 1 if the weight loss rate (wt%) is less than 0.20 Class 2 when the rate is less than 0.20 to 0.36, Class 3 when the rate of weight loss is less than 0.35 to 0.65, Class 4 when the rate of weight loss is less than 0.65 to 1.20, When the weight loss rate is 1.20 to less than 2.20, it is class 5, and when the weight loss rate is 2.20 or more, it is class 6. The acid resistance of the glass is better as the number of classes is smaller. Means that.

(Measurement of viscosity)
A glass sample of φ7 mm × 7 mmt is obtained using a precision cutting machine and a small-diameter drilling machine. Viscosity measurement was performed at log η = 5 to 9 poise using a glass parallel plate viscometer. The measured temperature when log η = 5 is shown in Tables 1-3.

As shown in Tables 1 to 3, the low-melting glass of Examples of the present invention has a thermal expansion coefficient (α) in the range of 107 to 138 × 10 ⁻⁷ / ° C. in the temperature range of 30 to 250 ° C. Compared with the comparative example shown in Table 3, it is much smaller and has a thermal expansion coefficient similar to or equivalent to the thermal expansion coefficient (about 85 to 107 × 10 ⁻⁷ / ° C.) of stainless steel or hard glass. . Moreover, water resistance is also low with the 1st-4th grade. Therefore, it is suitable for use in sealing electronic parts and the like that have a small coefficient of thermal expansion and are preferably sealed at a low temperature, such as semiconductor light emitting devices and photovoltaic power generation devices.

  Moreover, the DTA measurement result of Example 5 is shown in FIG. From the measurement results, the Tg of this example is recognized as 340 ° C. In the conventional sealing glass, although a crystallization peak appears in the region of 60 ° C. to 150 ° C. high from Tg, no clear crystallization peak was observed in the glass of this example. That is, the glass of the present invention can be said to be a glass that is difficult to crystallize.

  As described above, the glass according to the present invention has a low glass transition point (Tg), can seal electronic parts and the like at low temperatures, is chemically stable, has adhesive strength and chemical durability. The property is excellent. Moreover, since it is not necessary to contain a fluorine component, even if it is used for sealing electronic parts or the like, its quality is not adversely affected, so that the reliability of electronic parts and the like can be improved. Furthermore, since lead is not contained, there is an advantage that no cost is required for environmental measures. In addition to the above-described effects, the glass according to the present invention is a circuit for electronic components that is made of a material having a small thermal expansion coefficient, such as a semiconductor light emitting element and a solar power generation device, at a low temperature while maintaining a low sealing temperature. It is possible to perform sealing and the like without damaging the substrate and the like by heat, and the effect of further increasing the adhesive strength and mechanical strength is also achieved.

Claims (5)

In mol% display based on oxide,
30% to 55% of _P 2 _O 5,
10% to 40% ZnO,
Of _{0.01% ~30% Al 2 O 3} ,
0% to 30% R ₂ O (where R is one or more selected from Li, Na, K, Cs)
A glass having a ratio of Al ₂ O ₃ / P ₂ O ₅ expressed by mol% based on an oxide of 0.01 to 1 inclusive. In mol% display based on oxide,
0-15% SiO ₂ and / or
0% to 30% of _Al 2 _{O 3} and / or,
0-30% B ₂ O ₃ and / or
0-20% MgO and / or
0-20% CaO and / or
0-20% SrO and / or
0-20% BaO and / or
0-30% ZrO ₂ and / or
0-30% TiO ₂
The glass of Claim 1 containing each component of these. In mol% display based on oxide,
0-20% Bi ₂ O ₃ and / or
0-20% TeO ₂ and / or
0-20% CuO and / or
From 0% to 5% of _La 2 _{O 3} and / or,
0% to 5% Y ₂ O ₃ and / or
From 0% to 5% of _Gd 2 _{O 3} and / or,
0% to 10% WO ₃ and / or
0-10% MoO ₃ and / or
0% to 5% Nb ₂ O ₅
The glass of Claim 1 or 2 containing each component of these.   The Tg is 450 ° C. or lower, the crystallization temperature is 500 ° C. or higher, and the weight loss after immersion in boiling water for 60 minutes is less than 0.60 wt%. The glass described. 5. The glass according to claim 1, wherein an average linear thermal expansion coefficient is 150 × 10 ⁻⁷ / ° C. or less at 30 ° C. to 250 ° C. 5.