PHOSPHATE GLASS AND LIGHT-EMITTING DEVICE USING SAME

The present invention relates to phosphate glass and a light emitting device in which the phosphate glass is used.

High-intensity light emitting elements such as light emitting diodes (LEDs) have been actively developed in recent years. In a general method of using a light emitting diode as a light emitting element, the light emitting diode is combined with a material with which the light emitting diode is coated to form a device.

As such a coating material, an organic polymer, a silicon resin, or the like is generally used, but from the viewpoints of light resistance, gas permeability, heat resistance, and chemical durability, oxide glass that is easy to mold is the most suitable.

However, ordinary oxide glass is produced with a melting method in which an oxide raw material powder is once heated to 1,000° C. or higher and cooled in order to obtain a uniform melt. Such a high temperature far exceeds the heat-resistant temperature of a light emitting element, and therefore such a high-temperature melting method cannot be used.

Meanwhile, oxide glass having a characteristic of softening at a low temperature is referred to as low melting point glass. Low melting point glass is mainly used for coating and sealing in electronic components, and therefore the working temperature of low melting point glass is approximately 600° C. or lower. However, low melting point glass in which lead is used is conventionally difficult to use as a coating material due to regulation in accordance with Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS).

Therefore, low melting point glass having a composition designed to substitute lead with a plurality of other elements is actively developed by industry-academic-government. Among the developed glass, one alternative candidate is low melting point glass containing bismuth, vanadium, and the like, and this glass has both excellent chemical durability and a low melting point (Patent Documents 1 and 2).

However, in many cases, such glass is colored and is difficult to use as low melting point glass for optical applications as described above.

Therefore, development of inorganic oxide glass having both transparency in a near-ultraviolet to visible region and a softening characteristic at a low temperature is earnestly desired by the industry.

As one composition for such optical applications at low temperatures, oxide glass containing 50 mol % or more of zinc is known (Non-Patent Document 1). Such a composition is known as a lead-free low-melting point frit, and has permeability depending on the composition even in an ultraviolet region. However, the lead-free low-melting point frit is to be manufactured through a plurality of steps, such as a step of adjusting the particle size of a frit produced by melting glass, and the glass is essentially to be melted once at a temperature close to 1,000° C.

Examples of a production method that enables production at a low temperature include a sol-gel method in which a solution is used. However, even in this method, heating to 500° C. or higher is generally to be performed in order to obtain an oxide material.

As an oxide material that can be produced at a low temperature, a glass thin film containing ZnO is known (Patent Document 3, Non-Patent Document 2). Patent Document 3 describes that an amorphous glass thin film containing three components of SnO—ZnO—P₂O₅can be formed into a film in the order of micrometer at a low temperature of about 400° C. in a single step by controlling the composition.

A method is also known in which bulk low melting point glass is produced using a zinc compound and phosphoric acid as starting raw materials (Patent Document 4). This glass contains 55 to 90 mol % of P₂O₅and 10 to 45 mol % of ZnO in terms of mole percentage based on oxides, and can be produced at 500° C.

• Patent document 1: Japanese Patent Laid-open Publication No. 2009-221048
• Patent document 2: Japanese Patent Laid-open Publication No. 2019-038722
• Patent document 3: Japanese Patent Laid-open Publication No. 2012-160697
• Patent document 4: Japanese Patent Laid-open Publication No. 2017-049526

• Non-Patent Document 1: Morena, Journal of Non-Crystalline Solids, 2000, vol. 263-264, p. 382
• Non-Patent Document 2: Masai et al., Scientific Reports, 2015, vol. 5, p. 11224
• Non-Patent Document 3: C. A. ANGELL, Journal of Non-Crystalline Solids, 1988, vol. 102, p. 205-221

However, the glass described in Patent Document 4 has low durability against water, and has a problem of being easily dissolved in water when immersed in water. Patent Document 4 describes that the physical property can be adjusted by adding 0.1 to 5 mol % of another component with respect to two components of P₂O₅and ZnO, but improvement in the durability has not been confirmed.

Therefore, according to an embodiment of the present invention, a phosphate glass is provided that has a low melting point and has excellent water resistance while maintaining a glass structure.

Furthermore, according to an embodiment of the present invention, a light emitting device is provided that includes phosphate glass having a low melting point and having excellent water resistance while maintaining a glass structure.

(Configuration 1)

According to an embodiment of the present invention, the phosphate glass includes, in terms of mole percentage based on oxides, 55 to 65 [mol %] of P₂O₅, 10 to 27 [mol %] of ZnO, 0.5 to 7 [mol %] of R₂O₃being at least one of Al₂O₃, Ga₂O₃, or Y₂O₃, 0.5 to 3.5 [mol %] of a lanthanoid oxide L₂O₃being at least one of La₂O₃, Ce₂O₃, Pr₂O₃, Nd₂O₃, Pm₂O₃, Sm₂O₃, Eu₂O₃, Gd₂O₃, Tb₂O₃, Dy₂O₃, Ho₂O₃, Er₂O₃, Tm₂O₃, Yb₂O₃, or Lu₂O₃, and 4 to 15 [mol %] of X₂O being at least one of Li₂O, Na₂O, K₂O, Rb₂O, Cs₂O, or Fr₂O, and the phosphate glass has a glass transition temperature of lower than 490° C.

(Configuration 2)

In the configuration 1, the total content of the P₂O₅and the ZnO is 68 to 85 [mol %], and the total content of the R₂O₃and the L₂O₃is 1 to 10 [mol %].

(Configuration 3)

In the configuration 1 or 2, the glass transition temperature is 240° C. or lower.

(Configuration 4)

In the configuration 3, the content of the Al₂O₃is 1 to 5 [mol %].

(Configuration 5)

In the configuration 3 or 4, the phosphate glass further includes 0.001 to 10.0 [mol %] of SnO.

(Configuration 6)

In the configuration 1 or 2, the glass transition temperature is higher than 240° C.

(Configuration 7)

In any one of the configurations 1 to 6, the phosphate glass further includes 5 to 12 [mol %] of QO being at least one of BaO, SrO, CaO, or MgO.

(Configuration 8)

In any one of the configurations 1 to 7, the phosphate glass further includes 0.1 to 9 [mol %] of SiO₂.

(Configuration 9)

According to an embodiment of the present invention, the light emitting device includes a light emitting element and a coating material. The light emitting element is coated with the coating material. The coating material includes the phosphate glass in any one of the configurations 1 to 8.

A phosphate glass can be obtained that has a low melting point and has excellent water resistance while maintaining a glass structure.

The phosphate glass PGS according to an embodiment of the present invention includes, in terms of mole percentage based on oxides, 55 to 65 [mol %] of P₂O₅, 10 to 27 [mol %] of ZnO, 0.5 to 7 [mol %] of R₂O₃being at least one of Al₂O₃, Ga₂O₃, or Y₂O₃, 0.5 to 3.5 [mol %] of a lanthanoid oxide L₂O₃being at least one of La₂O₃, Ce₂O₃, Pr₂O₃, Nd₂O₃, Pm₂O₃, Sm₂O₃, Eu₂O₃, Gd₂O₃, Tb₂O₃, Dy₂O₃, Ho₂O₃, Er₂O₃, Tm₂O₃, Yb₂O₃, or Lu₂O₃, and 4 to 15 [mol %] of X₂O being at least one of Li₂O, Na₂O, K₂O, Rb₂O, Cs₂O, or Fr₂O, and the phosphate glass PGS has a glass transition temperature Tg of lower than 490° C.

The P₂O₅and the ZnO are components that form a network of glass (components that stabilize glass). The R₂O₃and the L₂O₃are components that increase the durability against water (water resistance) and the glass transition temperature Tg. The P₂O₅and the X₂O are components that decrease the water resistance and the glass transition temperature Tg.

The phosphate glass PGS may have a glass transition temperature Tg of 240° C. or lower. The phosphate glass PGS may have a glass transition temperature Tg of higher than 240° C. and lower than 400° C.

The phosphate glass PGS is characterized in that the glass is stabilized by 55 to 65 [mol %] of P₂O₅and 10 to 27 [mol %] of ZnO, and that the water resistance is improved by 0.5 to 7 [mol %] of R₂O₃and 0.5 to 3.5 [mol %] of L₂O₃. That is, the phosphate glass PGS achieves stabilization of the glass and improvement in the water resistance by a balance between the total content of P₂O₅and ZnO and the total content of R₂O₃and L₂O₃.

In an embodiment of the present invention, the water resistance of the phosphate glass PGS is evaluated with any one method of the following (1) and (2).

(1) The water resistance is evaluated using a measurement result of the mass loss rate ΔW of the phosphate glass immersed in water having a pH of 7 (room temperature) for 360 minutes.

(2) The water resistance is evaluated using a measurement result of the mass loss rate ΔW of the phosphate glass immersed in water having a pH of 7 (70° C.) for 180 minutes.

In both the methods (1) and (2), a smaller value of the loss rate ΔW indicates more excellent water resistance. In the case of evaluating the water resistance with the method (1), the water resistance is determined to be excellent when the loss rate ΔW is smaller than 30 [%], and in the case of evaluating the water resistance with the method (2), the water resistance is determined to be excellent when the loss rate ΔW is smaller than 0.6 [%].

From the viewpoint of the loss rate ΔW, the phosphate glass PGS more preferably includes 55.8 to 63.0 [mol %] of P₂O₅, 1.0 to 7.0 [mol %] of R₂O₃, and 1.0 to 3.5 [mol %] of L₂O₃, and still more preferably includes 1.0 to 6.1 [mol %] of R₂O₃and 1.0 to 3.0 [mol %] of L₂O₃. From the viewpoint of the glass transition temperature Tg, the phosphate glass PGS more preferably includes 0.7 to 4.9 [mol %] of R₂O₃, and still more preferably includes 0.7 to 3.5 [mol %] of R₂O₃and 0.7 to 3.0 [mol %] of L₂O₃. In consideration of both the loss rate ΔW and the glass transition temperature Tg, the phosphate glass PGS more preferably includes 55.8 to 63.0 [mol %] of P₂O₅, 1.0 to 4.9 [mol %] of R₂O₃, and 1.0 to 3.5 [mol %] of L₂O₃, and still more preferably includes 1.0 to 3.5 [mol %] of R₂O₃and 1.0 to 3.0 [mol %] of L₂O₃.

The phosphate glass PGS may further include, in addition to P₂O₅, ZnO, R₂O₃, L₂O₃, and X₂O, 0.001 to 10.0 [mol %] of SnO in terms of mole percentage based on oxides. If the phosphate glass PGS includes 0.001 to 10.0 [mol %] of SnO, the wavelength λ_TRof the light at the transmission end in the ultraviolet region can be controlled according to the content of SnO while the glass network structure is maintained. More specifically, the wavelength λ_TRof the light at the transmission end shifts to the long wavelength side in the ultraviolet region as the content of SnO increases, and shifts to the short wavelength side in the ultraviolet region as the content of SnO decreases.

The phosphate glass PGS may include, in addition to P₂O₅, ZnO, R₂O₃, L₂O₃, and X₂O, 5 to 12 [mol %] of QO being at least one of BaO, SrO, CaO, or MgO in terms of mole percentage based on oxides. Similarly to X₂O, QO is classified as a network modifier in oxide glass, but has a smaller effect of decreasing the glass transition temperature Tg and the water resistance than X₂O.

Furthermore, the phosphate glass PGS may include, in addition to P₂O₅, ZnO, R₂O₃, L₂O₃, and X₂O, 0.1 to 9 [mol %] of SiO₂in terms of mole percentage based on oxides. If the phosphate glass PGS includes SiO₂as a component, the phosphate glass PGS achieving both stabilization of the glass and the water resistance can be manufactured even when the manufacturing process has an atmosphere including SiO₂.

Lanthanoid elements that can be used in an embodiment of the present invention are lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

FIG. 1 is a process chart showing a method for manufacturing the phosphate glass PGS. At the start of manufacturing the phosphate glass PGS with reference to FIG. 1, raw materials (any one of H₃PO₄, (NH₄)H₂PO₄, and (NH₄)₂HPO₄and any one of ZnO, R(OH)₃being at least one of Al(OH)₃, Ga(OH)₃, or Y(OH)₃, L₂O₃, and an alkali metal phosphate being at least one of LiPO₃, Li₃PO₄, LiH₂PO₄, Li₂HPO₄, NaPO₃, Na₃PO₄, NaH₂PO₄, Na₂HPO₄, KPO₃, K₃PO₄, KH₂PO₄, K₂HPO₄, RbPO₃, Rb₃PO₄, RbH₂PO₄, Rb₂HPO₄, CsPO₃, Cs₃PO₄, CsH₂PO₄, Cs₂HPO₄, FrPO₃, Fr₃PO₄, FrH₂PO₄, or Fr₂HPO₄) are weighed so that the content of each of P₂O₅, ZnO, R₂O₃being at least one of Al₂O₃, Ga₂O₃, or Y₂O₃, L₂O₃being at least one of La₂O₃, Ce₂O₃, Pr₂O₃, Nd₂O₃, Pm₂O₃, Sm₂O₃, Eu₂O₃, Gd₂O₃, Tb₂O₃, Dy₂O₃, Ho₂O₃, Er₂O₃, Tm₂O₃, Yb₂O₃, or Lu₂O₃, and X₂O being at least one of Li₂O, Na₂O, K₂O, Rb₂O, Cs₂O, or Fr₂O is a predetermined content in terms of mole percentage based on oxides (step S1).

Then, the weighed raw materials (any one of H₃PO₄, (NH₄)H₂PO₄, and (NH₄)₂HPO₄and any one of ZnO, R(OH)₃, L₂O₃, and an alkali metal phosphate) are mixed to produce a mixture (step S2).

In the case of using H₃PO₄as a raw material (“YES” in the step S3), the mixture is heated at 200° C. for a predetermined time (20 to 60 minutes) in the air to produce a precursor liquid (step S4).

In the case of using no H₃PO₄as a raw material (“NO” in the step S3), or after the step S4, the precursor liquid is heat-treated at 400° C. for a predetermined time (10 to 60 minutes) (step S5). Then, the precursor liquid is placed in an electric furnace and heated at 500° C. for a predetermined time (10 to 30 minutes and preferably 10 to 20 minutes) to melt the mixture (step S6), and then the mixture is naturally cooled (step S7). In the case of melting the mixture at 800° C., the precursor liquid is placed in an electric furnace and heated at 800° C. for a predetermined time (10 to 30 minutes and preferably 10 to 20 minutes) to melt the mixture (step S6), and then the mixture is naturally cooled (step S7). In the case of melting the mixture at a temperature between 500° C. and 800° C. in the step S6, either the melting method at 500° C. or the melting method at 800° C. described above is used. As a result, the phosphate glass PGS is manufactured. In the case of using a vacuum electric furnace in the step S6, the pressure in the vacuum electric furnace is, for example, 1 kPa to 40 kPa.

As described above, the phosphate glass PGS according to an embodiment of the present invention is manufactured by melting the raw materials at a temperature of 500° C. to 800° C.

In a melt-quenching method as a conventional glass manufacturing method, raw materials are melted at a temperature of 1,000° C. or higher, but in an embodiment of the present invention, the raw materials are melted at a temperature of 500° C. to 800° C. Therefore, in the manufacturing method in an embodiment of the present invention, the temperature is lower than in a conventional glass manufacturing method, and energy used during synthesis can be suppressed. As a result, the environmental load can be reduced.

FIG. 2 is a schematic view of the light emitting device according to an embodiment of the present invention. As can be seen with reference to FIG. 2, a light emitting device 10 according to an embodiment of the present invention includes a light emitting element 1 and a coating material 2. The light emitting element 1 is a light emitting element having a light emission wavelength in the ultraviolet region, and is, for example, an LED.

The coating material 2 is disposed on the light emitting element 1 in contact with the light emitting surface of the light emitting element 1. The coating material 2 includes the phosphate glass PGS.

Hereinafter, the phosphate glass PGS will be described in detail with reference to Examples. Note that the sum of the numerical values of mole percentage may not be 100 [mol %] because the values are significant figures.

Each of 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O was weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 59.6 [mol %], 20.7 [mol %], 2.6 [mol %], 1.0 [mol %], 7.8 [mol %], and 8.3 [mol %], respectively, in terms of mole percentage based on oxides.

Then, the weighed raw materials were mixed, and the resulting mixture was heated at 200° C. for 30 minutes in the air to obtain a precursor liquid. Next, the precursor liquid was heated at 400° C. for 20 minutes, then the heated precursor liquid was put into a vacuum electric furnace of model number KDF-75 Plus manufactured by DENKEN-HIGHDENTAL Co., Ltd., the pressure in the vacuum electric furnace was set to 40 kPa, and the precursor liquid was heated at 500° C. for 15 minutes and then naturally cooled to produce phosphate glass PGS-1 in Example 1.

Phosphate glass PGS-2 in Example 2 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 62.1 [mol %], 22.6 [mol %], 2.8 [mol %], 1.1 [mol %], 5.7 [mol %], and 5.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-3 in Example 3 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 59.8 [mol %], 21.7 [mol %], 3.3 [mol %], 1.1 [mol %], 5.4 [mol %], and 8.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-4 in Example 4 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 64.9 [mol %], 10.8 [mol %], 2.7 [mol %], 2.2 [mol %], 10.8 [mol %], and 8.6 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-5 in Example 5 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 59.5 [mol %], 21.6 [mol %], 2.7 [mol %], 2.2 [mol %], 5.4 [mol %], and 8.6 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-6 in Example 6 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 56.1 [mol %], 25.4 [mol %], 2.6 [mol %], 2.6 [mol %], 5.1 [mol %], and 8.2 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-7 in Example 7 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 61.0 [mol %], 16.7 [mol %], 2.8 [mol %], 2.8 [mol %], 5.6 [mol %], and 11.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-8 in Example 8 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-9 in Example 9 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 58.5 [mol %], 14.6 [mol %], 4.9 [mol %], 2.4 [mol %], 9.8 [mol %], and 9.8 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-10 in Example 10 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, Lu₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Lu₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 2.0 [mol %], 1.5 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-11 in Example 11 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 1.5 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-12 in Example 12 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.5 [mol %], 0.5 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-13 in Example 13 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], 9.3 [mol %], and 0.001 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-14 in Example 14 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], 9.3 [mol %], and 0.010 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-15 in Example 15 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 62.7 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], 9.3 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-16 in Example 16 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 62.1 [mol %], 17.3 [mol %], 2.9 [mol %], 2.9 [mol %], 4.6 [mol %], 9.2 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-17 in Example 17 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 57.1 [mol %], 15.8 [mol %], 2.6 [mol %], 2.6 [mol %], 4.3 [mol %], 8.5 [mol %], and 9.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-18 in Example 18 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 1.4 [mol %], 2.9 [mol %], 1.5 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-19 in Example 19 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, Lu₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 2.0 [mol %], 1.0 [mol %], 2.0 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-20 in Example 20 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, Lu₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, Ga₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 1.5 [mol %], 1.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-21 in Example 21 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Lu₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Lu₂O₃, Ga₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-22 in Example 22 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Lu₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Lu₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 3.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-23 in Example 23 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, Lu₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 1.5 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-24 in Example 24 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-25 in Example 25 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, La₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 3.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-26 in Example 26 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 2.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-27 in Example 27 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Lu₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Lu₂O₃, Ga₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 2.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-28 in Example 28 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ca(H₂PO₄)₂.H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and CaO were 62.1 [mol %], 22.6 [mol %], 2.8 [mol %], 1.1 [mol %], 5.7 [mol %], and 5.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-28-2 in Example 28-2 was produced in the same manner as in Example 1 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, and SrO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and SrO were 62.1 [mol %], 22.6 [mol %], 2.8 [mol %], 1.1 [mol %], 5.7 [mol %], and 5.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-29 in Example 29 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, and KPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, and K₂O were 59.0 [mol %], 20.0 [mol %], 3.5 [mol %], 3.0 [mol %], and 14.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-30 in Example 30 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, and LiPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, and Li₂O were 62.5 [mol %], 21.5 [mol %], 1.5 [mol %], 2.5 [mol %], and 12.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-31 in Example 31 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, and NaPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, and Na₂O were 62.5 [mol %], 21.5 [mol %], 1.5 [mol %], 2.5 [mol %], and 12.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-32 in Example 32 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, NaPO₃, and KPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Na₂O, and K₂O were 62.0 [mol %], 21.0 [mol %], 2.0 [mol %], 3.0 [mol %], 6.0 [mol %], and 6.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-33 in Example 33 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, Lu₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-34 in Example 34 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 58.5 [mol %], 22.0 [mol %], 2.9 [mol %], 2.2 [mol %], 5.5 [mol %], 8.8 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-35 in Example 35 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 62.1 [mol %], 17.2 [mol %], 2.9 [mol %], 2.9 [mol %], 4.6 [mol %], 9.2 [mol %], and 1.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-36 in Example 36 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and SiO₂were 59.0 [mol %], 20.0 [mol %], 1.0 [mol %], 3.0 [mol %], 14.5 [mol %], and 2.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-37 in Example 37 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 57.0 [mol %], 12.5 [mol %], 1.0 [mol %], 1.0 [mol %], 11.5 [mol %], 10.0 [mol %], and 7.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-38 in Example 38 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 56.7 [mol %], 11.7 [mol %], 0.7 [mol %], 0.7 [mol %], 11.9 [mol %], 9.8 [mol %], and 8.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-39 in Example 39 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 2.0 [mol %], 3.0 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-40 in Example 40 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, and BaO were 61.0 [mol %], 20.5 [mol %], 1.5 [mol %], 2.0 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-41 in Example 41 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, La₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 3.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-42 in Example 42 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Lu₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Lu₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], and 10.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-43 in Example 43 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 2.0 [mol %], 2.0 [mol %], 7.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-44 in Example 44 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, LiPO₃, NaPO₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Li₂O, Na₂O, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 1.5 [mol %], 1.0 [mol %], 1.0 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-45 in Example 45 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, and Ca(H₂PO₄)₂.H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and CaO were 60.0 [mol %], 20.0 [mol %], 2.0 [mol %], 2.0 [mol %], 8.0 [mol %], and 8.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-46 in Example 46 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-47 in Example 47 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, and MgO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and MgO were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 3.0 [mol %], 9.0 [mol %], and 6.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-48 in Example 48 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, and KPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, and K₂O were 62.5 [mol %], 22.0 [mol %], 1.5 [mol %], 2.0 [mol %], 2.0 [mol %], and 10.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-49 in Example 49 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 2.5 [mol %], 1.0 [mol %], 7.0 [mol %], and 8.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-50 in Example 50 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 2.5 [mol %], 6.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-51 in Example 51 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and SiO₂were 62.5 [mol %], 21.0 [mol %], 2.0 [mol %], 3.0 [mol %], 10.0 [mol %], and 1.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-52 in Example 52 was produced in the same manner as in Example 1 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, and KPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, and K₂O were 63.0 [mol %], 22.0 [mol %], 2.0 [mol %], 3.0 [mol %], and 10.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-53 in Example 53 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, Lu₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, K₂O, and BaO were 61.0 [mol %], 20.0 [mol %], 2.0 [mol %], 3.0 [mol %], 6.0 [mol %], and 8.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-54 in Example 54 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Cu₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and CU₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-55 in Example 55 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Ag₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and Ag₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-56 in Example 56 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and MnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and MnO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-57 in Example 57 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Cu₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and CU₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.9 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-58 in Example 58 was produced in the same manner as in Example 1 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Ag₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and Ag₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.9 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-59 in Example 59 was produced in the same manner as in Example 1 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and MnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and MnO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.9 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-60 in Example 60 was produced in the same manner as in Example 1 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-1 in Comparative Example 1 was produced in the same manner as in Example 1 except that 85% H₃PO₄and ZnO were weighed so that the contents of P₂O₅and ZnO were 50.0 [mol %] and 50.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-2 in Comparative Example 2 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, and BaO were 60.0 [mol %], 30.0 [mol %], and 10.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-3 in Comparative Example 3 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, K₂O, and BaO were 59.1 [mol %], 27.3 [mol %], 4.5 [mol %], and 9.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-4 in Comparative Example 4 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, K₂O, and BaO were 57.9 [mol %], 26.3 [mol %], 5.3 [mol %], and 10.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-5 in Comparative Example 5 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, and BaO were 58.8 [mol %], 29.4 [mol %], and 11.8 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-6 in Comparative Example 6 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, K₂O, and BaO were 59.5 [mol %], 21.6 [mol %], 2.7 [mol %], 5.4 [mol %], and 10.8 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-7 in Comparative Example 7 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, K₂O, and BaO were 62.9 [mol %], 22.9 [mol %], 2.9 [mol %], 5.6 [mol %], and 5.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-8 in Comparative Example 8 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, K₂O, and BaO were 61.1 [mol %], 22.2 [mol %], 5.6 [mol %], 5.5 [mol %], and 5.6 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-9 in Comparative Example 9 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, K₂O, and BaO were 62.9 [mol %], 22.9 [mol %], 2.9 [mol %], 5.6 [mol %], and 5.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-10 in Comparative Example 10 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, K₂O, and BaO were 59.1 [mol %], 21.5 [mol %], 5.4 [mol %], 5.4 [mol %], and 8.6 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-11 in Comparative Example 11 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, K₂O, and BaO were 58.7 [mol %], 20.4 [mol %], 5.1 [mol %], 7.7 [mol %], and 8.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-12 in Comparative Example 12 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 62.8 [mol %], 5.8 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], 9.3 [mol %], and 11.6 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-13 in Comparative Example 13 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 53.5 [mol %], 14.9 [mol %], 2.5 [mol %], 2.5 [mol %], 4.0 [mol %], 7.8 [mol %], and 14.8 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-14 in Comparative Example 14 was produced in the same manner as in Example 1 except that 85% H₃PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 59.3 [mol %], 5.5 [mol %], 2.7 [mol %], 2.7 [mol %], 4.5 [mol %], 8.8 [mol %], and 16.5 [mol %], respectively, in terms of mole percentage based on oxides.

In Examples 1 to 60 and Comparative Examples 1 to 14, phosphate glass was produced through melting at a temperature of 500° C.

Each of (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O was weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 58.5 [mol %], 22.1 [mol %], 2.9 [mol %], 2.2 [mol %], 5.5 [mol %], and 8.8 [mol %], respectively, in terms of mole percentage based on oxides.

Then, the weighed raw materials were mixed, and the resulting mixture was heated at 400° C. for 20 minutes in the air. Next, the heated precursor was put into a high-speed heating electric furnace of model number SH manufactured by MOTOYAMA, heated at 800° C. for 15 minutes, and then naturally cooled to produce phosphate glass PGS-61 in Example 61.

Phosphate glass PGS-62 in Example 62 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 57.1 [mol %], 21.0 [mol %], 2.4 [mol %], 2.4 [mol %], 9.5 [mol %], and 7.6 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-63 in Example 63 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 57.6 [mol %], 13.1 [mol %], 6.1 [mol %], 3.0 [mol %], 10.1 [mol %], and 10.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-64 in Example 64 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 58.5 [mol %], 14.6 [mol %], 4.9 [mol %], 2.4 [mol %], 9.8 [mol %], and 9.8 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-65 in Example 65 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-66 in Example 66 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 56.1 [mol %], 25.5 [mol %], 2.55 [mol %], 2.55 [mol %], 5.1 [mol %], and 8.2 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-67 in Example 67 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 55.8 [mol %], 24.3 [mol %], 2.4 [mol %], 2.4 [mol %], 7.3 [mol %], and 7.8 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-68 in Example 68 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 59.6 [mol %], 20.7 [mol %], 2.6 [mol %], 1.0 [mol %], 7.8 [mol %], and 8.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-69 in Example 69 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 59.6 [mol %], 21.6 [mol %], 2.7 [mol %], 2.2 [mol %], 5.4 [mol %], and 8.6 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-70 in Example 70 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 62.5 [mol %], 21.7 [mol %], 2.7 [mol %], 2.2 [mol %], 5.5 [mol %], and 5.4 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-71 in Example 71 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, Lu₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Lu₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 2.0 [mol %], 1.5 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-72 in Example 72 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 1.5 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-73 in Example 73 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.5 [mol %], 0.5 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-74 in Example 74 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, and BaO were 62.5 [mol %], 21.7 [mol %], 2.2 [mol %], 2.7 [mol %], 5.5 [mol %], and 5.4 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-75 in Example 75 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, Lu₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 2.0 [mol %], 1.0 [mol %], 2.0 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-76 in Example 76 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, Lu₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, Ga₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 1.5 [mol %], 1.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-77 in Example 77 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, Lu₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 1.5 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-78 in Example 78 was produced in the same manner as in Example 61 except that (NH₄)₂HPO₄, ZnO, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, La₂O₃, K₂O, BaO, and Y₂O₃were 62.5 [mol %], 21.7 [mol %], 2.2 [mol %], 5.5 [mol %], 5.4 [mol %], and 2.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-79 in Example 79 was produced in the same manner as in Example 61 except that (NH₄)₂HPO₄, ZnO, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, La₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 3.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-80 in Example 80 was produced in the same manner as in Example 61 except that (NH₄)₂HPO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 2.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-81 in Example 81 was produced in the same manner as in Example 61 except that (NH₄)₂HPO₄, ZnO, Lu₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Lu₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 3.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-82 in Example 82 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Lu₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Lu₂O₃, Ga₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-83 in Example 83 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Lu₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, Lu₂O₃, Ga₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 2.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-84 in Example 84 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 2.9 [mol %], 2.9 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-85 in Example 85 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, LiPO₃, NaPO₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Li₂O, Na₂O, K₂O, and BaO were 62.5 [mol %], 21.8 [mol %], 2.7 [mol %], 2.2 [mol %], 1.8 [mol %], 1.8 [mol %], 1.8 [mol %], and 5.4 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-86 in Example 86 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, LiPO₃, NaPO₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Li₂O, Na₂O, K₂O, and BaO were 60.2 [mol %], 20.9 [mol %], 2.6 [mol %], 2.6 [mol %], 1.8 [mol %], 1.8 [mol %], 1.8 [mol %], and 8.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-87 in Example 87 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, and LiPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, and Li₂O were 62.5 [mol %], 21.5 [mol %], 1.5 [mol %], 2.5 [mol %], and 12.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-88 in Example 88 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, and NaPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, and Na₂O were 62.5 [mol %], 21.5 [mol %], 1.5 [mol %], 2.5 [mol %], and 12.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-89 in Example 89 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, NaPO₃, and KPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Na₂O, and K₂O were 62.0 [mol %], 21.0 [mol %], 2.0 [mol %], 3.0 [mol %], 6.0 [mol %], and 6.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-90 in Example 90 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ca(H₂PO₄)₂.H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and CaO were 62.1 [mol %], 22.6 [mol %], 2.8 [mol %], 1.1 [mol %], 5.7 [mol %], and 5.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-90-2 in Example 90-2 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, and SrO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and SrO were 62.1 [mol %], 22.6 [mol %], 2.8 [mol %], 1.1 [mol %], 5.7 [mol %], and 5.7 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-91 in Example 91 was produced in the same manner as in Example 61 except that (NH₄)₂HPO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 57.1 [mol %], 15.8 [mol %], 2.6 [mol %], 2.6 [mol %], 4.3 [mol %], 8.5 [mol %], and 9.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-92 in Example 92 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and MgO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and MgO were 59.0 [mol %], 20.0 [mol %], 1.0 [mol %], 3.0 [mol %], 14.0 [mol %], and 3.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-93 in Example 93 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, and KPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, and K₂O were 59.0 [mol %], 20.0 [mol %], 3.5 [mol %], 3.0 [mol %], and 14.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-94 in Example 94 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, and BaO were 62.8 [mol %], 17.4 [mol %], 1.4 [mol %], 2.9 [mol %], 1.5 [mol %], 4.7 [mol %], and 9.3 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-95 in Example 95 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 58.5 [mol %], 22.0 [mol %], 2.9 [mol %], 2.2 [mol %], 5.5 [mol %], 8.8 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-96 in Example 96 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 62.1 [mol %], 17.2 [mol %], 2.9 [mol %], 2.9 [mol %], 4.6 [mol %], 9.2 [mol %], and 1.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-97 in Example 97 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and SiO₂were 59.0 [mol %], 20.0 [mol %], 1.0 [mol %], 3.0 [mol %], 14.5 [mol %], and 2.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-98 in Example 98 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 57.5 [mol %], 13.5 [mol %], 2.0 [mol %], 2.0 [mol %], 10.0 [mol %], 10.0 [mol %], and 5.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-99 in Example 99 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 57.0 [mol %], 12.5 [mol %], 1.0 [mol %], 1.0 [mol %], 11.5 [mol %], 10.0 [mol %], and 7.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-100 in Example 100 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 56.7 [mol %], 11.7 [mol %], 0.7 [mol %], 0.7 [mol %], 11.9 [mol %], 9.8 [mol %], and 8.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-101 in Example 101 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 2.0 [mol %], 3.0 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-102 in Example 102 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, and BaO were 61.0 [mol %], 20.5 [mol %], 1.5 [mol %], 2.0 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-103 in Example 103 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Y₂O₃were weighed so that the contents of P₂O₅, ZnO, La₂O₃, K₂O, BaO, and Y₂O₃were 60.0 [mol %], 20.0 [mol %], 3.0 [mol %], 6.0 [mol %], 9.0 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-104 in Example 104 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Lu₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Lu₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], and 10.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-105 in Example 105 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, La₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 2.0 [mol %], 2.0 [mol %], 7.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-106 in Example 106 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, LiPO₃, NaPO₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Li₂O, Na₂O, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 1.5 [mol %], 1.0 [mol %], 1.0 [mol %], 6.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-107 in Example 107 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, and Ca(H₂PO₄)₂.H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and CaO were 60.0 [mol %], 20.0 [mol %], 2.0 [mol %], 2.0 [mol %], 8.0 [mol %], and 8.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-108 in Example 108 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SnO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-109 in Example 109 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, and MgO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and MgO were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 3.0 [mol %], 9.0 [mol %], and 6.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-110 in Example 110 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, and KPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, and K₂O were 62.5 [mol %], 22.0 [mol %], 1.5 [mol %], 2.0 [mol %], 2.0 [mol %], and 10.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-111 in Example 111 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 2.5 [mol %], 1.0 [mol %], 7.0 [mol %], and 8.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-112 in Example 112 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, Ba(OH)₂.8H₂O, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, BaO, and SiO₂were 60.0 [mol %], 20.0 [mol %], 1.5 [mol %], 2.5 [mol %], 6.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-113 in Example 113 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, KPO₃, and SiO₂were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and SiO₂were 62.5 [mol %], 21.0 [mol %], 2.0 [mol %], 3.0 [mol %], 10.0 [mol %], and 1.5 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-114 in Example 114 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, and KPO₃were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, and K₂O were 63.0 [mol %], 22.0 [mol %], 2.0 [mol %], 3.0 [mol %], and 10.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-115 in Example 115 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, Lu₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, Lu₂O₃, K₂O, and BaO were 61.0 [mol %], 20.0 [mol %], 2.0 [mol %], 3.0 [mol %], 6.0 [mol %], and 8.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-116 in Example 116 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Cu₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and CU₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-117 in Example 117 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Ag₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and Ag₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-118 in Example 118 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and MnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and MnO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 1.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-119 in Example 119 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Cu₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and CU₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.9 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-120 in Example 120 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Ag₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and Ag₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.9 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-121 in Example 121 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and MnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and MnO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 1.9 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.1 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-122 in Example 122 was produced in the same manner as in Example 61 except that 85% H₃PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, and BaO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], and 9.0 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-123 in Example 123 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Cu₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and CU₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.01 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-124 in Example 124 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and Ag₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and Ag₂O were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.01 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-125 in Example 125 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, KPO₃, Ba(OH)₂.8H₂O, and MnO were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Ga₂O₃, K₂O, BaO, and MnO were 60.0 [mol %], 20.0 [mol %], 1.0 [mol %], 1.0 [mol %], 2.0 [mol %], 7.0 [mol %], 9.0 [mol %], and 0.01 [mol %], respectively, in terms of mole percentage based on oxides.

Phosphate glass PGS-Comp-15 in Comparative Example 15 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, K₂O, and BaO were 65.7 [mol %], 23.5 [mol %], 2.9 [mol %], 3.0 [mol %], and 4.9 [mol %], respectively, in terms of mole percentage based on oxides.

An attempt was made to produce phosphate glass in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 69.2 [mol %], 4.4 [mol %], 3.5 [mol %], 1.8 [mol %], 18.5 [mol %], and 2.6 [mol %], respectively, in terms of mole percentage based on oxides, but no phosphate glass was obtained.

Phosphate glass PGS-Comp-17 in Comparative Example 17 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, K₂O, and BaO were 59.0 [mol %], 21.9 [mol %], 0.9 [mol %], 13.6 [mol %], and 4.6 [mol %], respectively, in terms of mole percentage based on oxides.

An attempt was made to produce phosphate glass in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 75.5 [mol %], 9.8 [mol %], 4.9 [mol %], 2.0 [mol %], 2.9 [mol %], and 4.9 [mol %], respectively, in terms of mole percentage based on oxides, but no phosphate glass was obtained.

An attempt was made to produce phosphate glass in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, and Al(OH)₃were weighed so that the contents of P₂O₅, ZnO, and Al₂O₃were 62.5 [mol %], 32.0 [mol %], and 5.5 [mol %], respectively, in terms of mole percentage based on oxides, but no phosphate glass was obtained.

Phosphate glass PGS-Comp-20 in Comparative Example 20 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, Lu₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, Lu₂O₃, K₂O, and BaO were 65.0 [mol %], 24.0 [mol %], 2.0 [mol %], 0.5 [mol %], 0.5 [mol %], 2.5 [mol %], and 5.5 [mol %], respectively, in terms of mole percentage based on oxides.

An attempt was made to produce phosphate glass in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, K₂O, and BaO were 63.4 [mol %], 24.3 [mol %], 5.4 [mol %], 4.9 [mol %], and 2.0 [mol %], respectively, in terms of mole percentage based on oxides, but no phosphate glass was obtained.

Phosphate glass PGS-Comp-22 in Comparative Example 22 was produced in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, K₂O, and BaO were 59.5 [mol %], 21.6 [mol %], 2.7 [mol %], 5.4 [mol %], and 10.8 [mol %], respectively, in terms of mole percentage based on oxides.

An attempt was made to produce phosphate glass in the same manner as in Example 61 except that (NH₄)H₂PO₄, ZnO, Al(OH)₃, La₂O₃, KPO₃, and Ba(OH)₂.8H₂O were weighed so that the contents of P₂O₅, ZnO, Al₂O₃, La₂O₃, K₂O, and BaO were 54.0 [mol %], 18.4 [mol %], 3.1 [mol %], 9.8 [mol %], 4.9 [mol %], and 9.8 [mol %], respectively, in terms of mole percentage based on oxides, but no phosphate glass was obtained.

In Examples 61 to 125 and Comparative Examples 15, 17, 20, and 22, phosphate glass was produced through melting at a temperature of 800° C.

The X-ray diffraction of phosphate glass was measured using an X-ray diffractometer of model number RINT2100 manufactured by Rigaku Corporation.

In addition, the glass transition temperature Tg of the phosphate glass was measured using a differential thermal analyzer of model number Thermo plus EVO2 manufactured by Rigaku Corporation.

Furthermore, the light transmission spectrum of the phosphate glass was measured using an ultraviolet-visible near-infrared spectrophotometer of model number UV4150 manufactured by Hitachi High-Tech Corporation.

Furthermore, the fluorescence spectrum of the phosphate glass was measured using a fluorescence spectrophotometer of model number F-7000 manufactured by Hitachi High-Tech Corporation.

Furthermore, the water resistance of the phosphate glass produced through melting at a temperature of 500° C. was evaluated with the above-described method (1). In addition, the water resistance of the phosphate glass produced through melting at a temperature of 800° C. was evaluated with the above-described method (2).

Table 1 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-1 to PGS-7 in Examples 1 to 7. Table 2 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-8 to PGS-14 in Examples 8 to 14. Table 3 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-15 to PGS-20 in Examples 15 to 20. Table 4 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-21 to PGS-26 in Examples 21 to 26.

Table 5 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-27 to PGS-32 in Examples 27 to 32. Table 6 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-33 to PGS-38 in Examples 33 to 38. Table 7 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-39 to PGS-44 in Examples 39 to 44. Table 8 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-45 to PGS-50 in Examples 45 to 50. Table 9 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-51 to PGS-56 in Examples 51 to 56. Table 10 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-57 to PGS-60 in Examples 57 to 60.

Table 11 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-Comp-1 to PGS-Comp-5 in Comparative Examples 1 to 5. Table 12 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-Comp-6 to PGS-Comp-10 in Comparative Examples 6 to 10. Table 13 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-Comp-11 to PGS-Comp-14 in Comparative Examples 11 to 14.

Table 14 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-61 to PGS-67 in Examples 61 to 67. Table 15 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-68 to PGS-74 in Examples 68 to 74. Table 16 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-75 to PGS-81 in Examples 75 to 81. Table 17 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-82 to PGS-87 in Examples 82 to 87. Table 18 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-88 to PGS-93 in Examples 88 to 93. Table 19 shows the contents of the components, the water resistance, and the glass transition temperature of the phosphate glass PGS-94 to PGS-100 in Examples 94 to 100.