阅读说明：本技术 导电性结晶化玻璃 (Conductive crystallized glass ) 是由 丹野义刚 松本奈绪美 于 2020-10-29 设计创作，主要内容包括：本发明的课题在于,提供一种具有导电性的结晶化玻璃、以及该结晶化玻璃的制造方法。本发明的结晶化玻璃含有Ti～(4+)作为玻璃成分,且具有室温下的体积电阻率为1.0×10～9Ω·cm以下的部分。(The present invention addresses the problem of providing a crystallized glass having electrical conductivity, and a method for producing the crystallized glass. The crystallized glass of the present invention contains Ti 4+ As a glass component and having a volume resistivity of 1.0X 10 at room temperature 9 The portion of Ω · cm or less.)

1. A crystallized glass containing Ti⁴⁺As a component of the glass, a glass,

the crystallized glass has a volume resistivity of 1.0X 10 at room temperature⁹The portion of Ω · cm or less.

2. A crystallized glass containing Ti⁴⁺As a component of the glass, a glass,

the crystallized glass has a surface resistivity of 1.0X 10 at room temperature⁹The fraction below Ω/□.

3. A crystallized glass containing anatase type TiO₂。

Technical Field

The present invention relates to a crystallized glass having conductivity, and a method for producing the crystallized glass.

Disclosure of Invention

Problems to be solved by the invention

The present invention aims to provide a crystallized glass having conductivity and a method for producing the crystallized glass.

Means for solving the problems

The gist of the present invention is as follows.

(1) A crystallized glass containing Ti⁴⁺As a component of the glass, a glass,

the crystallized glass has a volume resistivity of 1.0X 10 at room temperature⁹The portion of Ω · cm or less.

(2) A crystallized glass containing Ti⁴⁺As a component of the glass, a glass,

the crystallized glass has a surface resistivity of 1.0X 10 at room temperature⁹Omega/□ or lessAnd (4) partial.

(3) A crystallized glass containing anatase type TiO₂。

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, there can be provided a crystallized glass having conductivity and a method for producing the crystallized glass.

Drawings

FIG. 1 is a photograph of a crystallized glass sample obtained in example 5.

FIG. 2 is a photograph of a crystallized glass sample subjected to hydrogen reduction treatment obtained in example 5.

Fig. 3 is a photograph of a glass sample having a circuit formed on the surface thereof obtained in example 7.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail.

Embodiment 1

The glass of embodiment 1 contains Ti⁴⁺As a glass component. Ti⁴⁺The lower limit of the content of (b) is preferably 0.1 cation%, and more preferably 1 cation% and 3 cation% in the following order. In addition, Ti⁴⁺The upper limit of the content of (b) is preferably 45 cation%, and more preferably 42 cation% and 40 cation% in the following order.

Here, in the present specification, the cation% means a molar percentage in which the total content of all the cation components is 100%. The anionic component is only oxygen O.

By mixing Ti⁴⁺The content of (b) is within the above range, and a desired conductivity can be obtained in the crystallized glass after heat treatment in a reducing atmosphere described later.

The glass of embodiment 1 has a volume resistivity of 1.0X 10 at room temperature⁹The portion of Ω · cm or less. The region having the volume resistivity at room temperature in the above range may be a part of the glass or the entire region.

The glass of embodiment 1 is crystallized glass. The crystallized region may be a part of the glass or the entire glass. The crystallization also includes formation of crystal nuclei.

In the glass of embodiment 1, the crystallinity of the crystallized region may be 5% or more, and further may be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, or 80% or more.

As a glass material applicable to the glass of embodiment 1, there is no particular limitation, and for example, a glass having a composition disclosed in WO2017/006998 can be cited. The glass is crystallized by heat treatment according to a known method.

The glass of embodiment 1 is obtained by performing a heat treatment in a reducing atmosphere. By performing the heat treatment in the reducing atmosphere, the resistivity of the glass can be greatly reduced, and the conductivity can be ensured. In addition, the glass is colored black by heat treatment in a reducing atmosphere.

The reducing atmosphere may contain a gas having reducing ability. Examples of the gas having a reducing ability include hydrogen. Therefore, a hydrogen-containing gas is preferably used as the reducing atmosphere. The hydrogen concentration in the hydrogen-containing gas can be adjusted as appropriate. For example, a foaming gas containing hydrogen may be used. The foaming gas is a mixed gas containing hydrogen and nitrogen, and usually contains about 3 to 5 vol% of hydrogen. As the reducing atmosphere, a hydrogen-containing gas having a hydrogen concentration of 3 vol% or less may be used.

In the heat treatment in the reducing atmosphere, the heating is performed at 100 ℃ or higher and at a liquid phase temperature or lower. The heat treatment time can be appropriately adjusted depending on the degree of coloring to be achieved, desired conductivity, and the like.

The heat treatment in the reducing atmosphere may be performed when the glass is crystallized. That is, when the amorphous glass is crystallized by the heat treatment, the crystallization treatment may be performed in a reducing atmosphere, and the crystallization treatment and the heat treatment in the reducing atmosphere may be performed at the same time. The heat treatment in the reducing atmosphere may be performed after the glass is crystallized.

Embodiment 2

The glass of embodiment 2 contains Ti⁴⁺As a glass component. Ti⁴⁺The lower limit of the content of (b) is preferably 0.1 cation%, and more preferably 1 cation% and 3 cation% in the following order. In addition, Ti⁴⁺The upper limit of the content of (b) is preferably 45 cation%, and more preferably 42 cation% and 40 cation% in the following order.

By mixing Ti⁴⁺The content of (b) is within the above range, and a desired conductivity can be obtained in the crystallized glass after heat treatment in a reducing atmosphere described later.

The glass of embodiment 2 has a surface resistivity of 1.0 × 10 at room temperature⁹The fraction below Ω/□. The region having the surface resistivity at room temperature in the above range may be a part of the glass or the entire region.

The glass of embodiment 2 is crystallized glass. The crystallized region may be a part of the glass or the entire glass. The crystallization also includes formation of crystal nuclei.

The preferred crystallinity of the glass of embodiment 2 is the same as that of embodiment 1. The glass of embodiment 2 can be obtained by the same method as embodiment 1, and the heat treatment in the reducing atmosphere is applied as in embodiment 1.

Embodiment 3

The glass of embodiment 3 contains anatase type TiO₂. By containing anatase type TiO₂The resistivity can be reduced and the conductivity can be ensured.

The glass of embodiment 3 is crystallized glass. The crystallized region may be a part of the glass or the entire glass. The crystallization also includes formation of crystal nuclei.

In the glass of embodiment 3, the crystallinity of the crystallized region may be 5% or more, and further may be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, or 80% or more.

The glass of embodiment 3 is obtained by the same method as embodiment 1. In addition, heat treatment in a reducing atmosphere is applied as in embodiment 1.

Examples

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1

(example 1-1)

Glass samples having glass compositions shown in table a were produced by the following methods, and various evaluations were performed.

[ Table A ]

	P5+	B3+	Li+	Na+	K+	Ti4+	Nb5+	W6+	Total up to
										Cation%	34.9	0.0	0.5	0.0	7.9	30.1	22.1	4.5	100.0

The content of each cationic component in table a is the content (mole percentage) of each cationic component relative to the total amount of all cationic components, and is cationic% (mole), and the anionic component is only oxygen O.

[ production of glass ]

Orthophosphoric acid, metaphosphate, oxide, hydroxide, carbonate, and nitrate corresponding to the constituent components of the glass were prepared as raw materials, and the raw materials were weighed and blended so that the glass compositions of the obtained glasses became the compositions shown in table a, and the raw materials were sufficiently mixed. The obtained blended raw materials (batch raw materials) are put into a platinum crucible and heated at 1300 to 1450 ℃ for 2 to 3 hours to prepare molten glass. The molten glass is stirred for homogenization and, after fining, is cast into a mold preheated to an appropriate temperature. The glass after casting was subjected to a heat treatment at around the glass transition temperature Tg for about 1 hour and naturally cooled to room temperature in a furnace, thereby obtaining an amorphous glass sample I.

[ confirmation of glass composition ]

With respect to the obtained amorphous glass sample I, the contents of glass components were measured by inductively coupled plasma emission spectrometry (ICP-AES), and it was confirmed that the compositions were in accordance with those shown in table a.

[ glass transition temperature Tg ]

For the obtained amorphous glass sample I, the glass transition temperature Tg was measured. The Tg was measured at a temperature rise rate of 10 ℃ per minute using a differential scanning calorimetry analyzer (DSC8270) manufactured by Rigaku corporation, and was 658 ℃.

[ specific gravity ]

The specific gravity of the amorphous glass sample I thus obtained was measured by the archimedes method, and the results are shown in table 1.

[ average Linear thermal expansion coefficient ]

The obtained amorphous glass sample I was measured for its average linear thermal expansion coefficient at 100 to 300 ℃. The average linear expansion coefficient was measured according to the specification of JOGIS 08-2003. The sample was prepared into a round bar having a length of 20 mm. + -. 0.5mm and a diameter of 5 mm. + -. 0.5mm, and heated so as to be raised at a constant rate of 4 ℃ per minute in a state where a load of 98mN was applied to the sample, and the temperature and the elongation of the sample were measured. The results are shown in Table 1.

[ bending Strength (bending Strength) ]

For the obtained amorphous glass sample I, a glass composition was prepared by JIS R1601: the bending strength (bending strength) was measured by the 3-point bending test method defined in 2008. The measurement sample was set to 40mm × 10mm × 1mm in size, and the distance between the supporting points was set to 30 mm. The number of the detected objects was set to 5 or more, and the average value, the maximum value, and the minimum value of the obtained values are shown in table 1.

[ volume resistivity ]

The amorphous glass sample I thus obtained was measured for volume resistivity. A measuring device: the measurement conditions were as follows, Hiresta-UX MCP-800 manufactured by Mitsubishi Chemical Analytech corporation: the measurement was performed at a voltage of 500V using a volume resistance mode and a surface resistance mode. Volume resistivity of about 2.2X 10¹⁴Ω·cm。

(examples 1 to 2)

The amorphous glass sample I obtained in example 1-1 was subjected to a heat treatment (hydrogen reduction treatment) at 630 ℃ for 30 hours in a reducing atmosphere using a hydrogen-containing gas, to obtain an amorphous glass sample after the hydrogen reduction treatment.

For the reduction by hydrogenThe volume resistivity of the treated amorphous glass sample was measured in the same manner as in example 1-1, and was about 1.7X 10⁸Ω·cm。

(examples 1 to 3)

The amorphous glass sample I obtained in example 1-1 was held at 700 ℃ for 6 hours and then held at 850 ℃ for 3 hours (crystallization treatment), thereby obtaining a crystallized glass sample II.

The specific gravity, the average linear thermal expansion coefficient, and the bending strength of the crystallized glass sample II were measured in the same manner as in example 1-1, and the results are shown in table 1.

The volume resistivity of the crystallized glass sample II was measured in the same manner as in example 1-1 and was about 6.7X 10¹⁰Ω·cm。

(examples 1 to 4)

The crystallized glass sample II obtained in examples 1 to 3 was subjected to a heat treatment (hydrogen reduction treatment) at 580 ℃ for 60 hours in a reducing atmosphere using a hydrogen-containing gas, to obtain a crystallized glass sample III subjected to the hydrogen reduction treatment.

The specific gravity, the average linear thermal expansion coefficient, and the bending strength of the crystallized glass sample III subjected to the hydrogen reduction treatment were measured in the same manner as in example 1-1, and the results are shown in table 1.

The crystallized glass sample III which had been subjected to the hydrogen reduction treatment had a volume resistivity of about 3.8X 10 as measured in the same manner as in example 1-1⁴Ω·cm。

[ Table 1]

Example 2

(example 2-1)

The crystallized glass sample II obtained in examples 1 to 3 was identified by X-ray diffraction method. As a result, it was confirmed that the crystallized glass sample II containedWith anatase type titanium oxide TiO₂。

The results of calculating the crystallinity of the crystallized glass sample II obtained in examples 1 to 3 are shown in Table 2. The amorphous glass sample I obtained in example 1-1 was used as a standard sample.

(example 2-2)

The crystallized glass sample III obtained in example 1-4 and subjected to hydrogen reduction treatment was identified by X-ray diffraction method in the same manner as in example 2-1. As a result, it was confirmed that anatase type titanium oxide TiO was contained in crystallized glass sample III which had been subjected to hydrogen reduction treatment₂. It was also confirmed that crystallized glass sample III which had been subjected to hydrogen reduction treatment also contained crystals containing at least Nb (niobium), P (phosphorus), and O (oxygen). The crystallinity was calculated in the same manner as in example 2-1. The results are shown in Table 2.

[ Table 2]

The crystallinity of the corresponding phase 1 is calculated according to the following formula.

(degree of crystallinity X_cScattering intensity of amorphous part of unknown substance I'_aScattering intensity I of 100% amorphous sample_a100)

X_c＝{1－[(ΣI’_a)/(ΣI_a100)]}×100

Example 3

The crystallized glass samples II obtained in examples 1 to 3 and the crystallized glass samples III obtained in examples 1 to 4 and subjected to hydrogen reduction treatment were analyzed by X-ray diffraction to obtain diffraction patterns. The amorphous glass sample I obtained in example 1-1 was used as a standard sample.

From the diffraction pattern obtained by the X-ray diffraction analysis, it was confirmed that the position of the crystallization peak was not changed between the crystallized glass sample III and the crystallized glass sample II which had been subjected to the hydrogen reduction treatment.

Example 4

(example 4-1)

The amorphous glass sample I obtained in example 1-1 was held at 650 ℃ for 24 hours and then at 800 ℃ for 12 hours (crystallization treatment), thereby obtaining a crystallized glass sample IV having a crystallinity of 100%. The crystallized glass sample IV having 100% crystallinity obtained was identified by X-ray diffraction method in the same manner as in example 2-1. As a result, it was confirmed that the crystallized glass sample IV having a crystallinity of 100% contained anatase type titanium oxide TiO₂. It was confirmed that crystallized glass sample IV having a crystallinity of 100% also contained crystals containing at least Nb (niobium), P (phosphorus), and O (oxygen). The crystallinity was calculated in the same manner as in example 2-1. The results are shown in Table 3.

(example 4-2)

The crystallized glass sample II obtained in example 1-3 was identified by X-ray diffraction method in the same manner as in example 4-1. As a result, it was confirmed that TiO anatase titanium oxide was contained in the crystallized glass sample II₂. It was also confirmed that crystallized glass sample II further contained crystals containing at least Nb (niobium), P (phosphorus), and O (oxygen). The crystallinity was calculated in the same manner as in example 4-1. The results are shown in Table 3.

(examples 4 to 3)

The crystallized glass sample III obtained in example 1-4 and subjected to hydrogen reduction treatment was identified by X-ray diffraction method in the same manner as in example 4-1. As a result, it was confirmed that anatase type titanium oxide TiO was contained in crystallized glass sample III which had been subjected to hydrogen reduction treatment₂. It was also confirmed that crystallized glass sample III which had been subjected to hydrogen reduction treatment also contained crystals containing at least Nb (niobium), P (phosphorus), and O (oxygen). The crystallinity was calculated in the same manner as in example 4-1. The results are shown in Table 3.

[ Table 3]

Example 5

Glass samples having glass compositions shown in table B were produced by the following methods, and various evaluations were performed.

[ Table B ]

	P5+	Li+	K+	Mg2+	Ca2+	Ti4+	Nb5+	W6+	Total up to
										Cation%	34.9	0	16.4	4.0	4.0	30.1	6.08	4.5	100

Note that the content of each cationic component in table B is the content (mole percentage) of each cationic component relative to the total amount of all cationic components, and is cationic% (mole). The anionic component is only oxygen O.

[ production of glass ]

Orthophosphoric acid, metaphosphate, oxide, hydroxide, carbonate, and nitrate corresponding to the constituent components of the glass were prepared as raw materials, and the raw materials were weighed and blended so that the glass compositions of the obtained glasses became the compositions shown in table B, and the raw materials were sufficiently mixed. The obtained blended raw materials (batch raw materials) are put into a platinum crucible and heated at 1300 to 1450 ℃ for 2 to 3 hours to prepare molten glass. The molten glass is stirred for homogenization and, after fining, is cast into a mold preheated to an appropriate temperature. The glass after casting was subjected to a heat treatment at around the glass transition temperature Tg for about 1 hour, and naturally cooled to room temperature in a furnace, thereby obtaining an amorphous glass sample.

[ confirmation of glass composition ]

The contents of the glass components in the obtained amorphous glass samples were measured by inductively coupled plasma emission spectrometry (ICP-AES), and it was confirmed that the compositions were consistent with those shown in table B.

[ glass transition temperature Tg ]

The glass transition temperature Tg of the obtained amorphous glass sample was measured. The temperature was measured at a temperature increase rate of 10 ℃ per minute using a differential scanning calorimetry analyzer (DSC8270) manufactured by Rigaku corporation, and the Tg was 653 ℃.

[ volume resistivity, surface resistivity ]

The amorphous glass sample obtained was measured for volume resistivity and surface resistivity. A measuring device: Hiresta-UX MCP-800 manufactured by Mitsubishi Chemical Analytich, measurement conditions: the measurement was performed at a voltage of 500V using a volume resistance mode and a surface resistance mode. The results are shown in table 4 (amorphous glass samples are indicated as "untreated" in the column of crystallization treatment conditions).

[ crystallization ]

The obtained amorphous glass sample was crystallized. As shown in Table 4, the amorphous glass sample was heated to 650 ℃ and then to 700 to 800 ℃ at a temperature rise rate of 3 ℃/hr, to obtain a crystallized glass sample. The photograph of the crystallized glass sample thus obtained is shown in FIG. 1. The numbering in fig. 1 corresponds to the numbering in table 4.

The volume resistivity and surface resistivity of the crystallized glass samples were measured, and the results are shown in table 4 (shown in the column before the hydrogen reduction treatment). The volume resistivity of the crystallized glass sample was 10 irrespective of the temperature rise rate during the crystallization treatment¹⁰In the order of Ω · cm.

[ Hydrogen reduction treatment ]

The crystallized glass sample thus obtained was subjected to a heat treatment (hydrogen reduction treatment) at 610 ℃ for 2 hours in a reducing atmosphere using a hydrogen-containing gas, to obtain a crystallized glass sample subjected to hydrogen reduction treatment. Fig. 2 shows a photograph of the crystallized glass sample subjected to the hydrogen reduction treatment.

The volume resistivity and surface resistivity of the crystallized glass sample subjected to the hydrogen reduction treatment were measured, and the results are shown in table 4 (shown in the column after the hydrogen reduction treatment).

According to table 4, the volume resistivity of the crystallized glass sample subjected to the hydrogen reduction treatment was significantly lower than that of the crystallized glass sample before the hydrogen reduction treatment.

From this result, it is understood that the volume resistivity can be controlled by changing the production conditions of the crystallized glass.

The crystallized glass sample No.3 in table 4 (crystallization treatment condition 650 ℃→ 700 ℃ (3 ℃/hr)) was transparent to the naked eye, and had no porosity (i.e., porosity) that was likely to occur during crystallization. The crystallized glass after being made porous is likely to generate dust by friction. Therefore, the crystallized glass sample of No.3 which is not made porous is preferable because it is less likely to generate dust. Further, since the crystallized glass sample of No.3 had residual glass, it was excellent in processability at the time of machining such as polishing property, similarly to the amorphous glass.

[ Table 4]

Example 6

Samples made of oxide glasses having glass compositions (cation%) shown in table C were produced by the following methods, and various evaluations were performed.

[ Table C ]

	P5+	Ba2+	Na+	K+	Bi3+	Ti4+	Nb5+	W6+	Total up to
										Cation%	27.0	4.4	2.4	1.0	25.4	9.9	18.6	11.3	100.0

The content of each cationic component in table C is the content (molar percentage) of each cationic component relative to the total amount of all cationic components, and is cationic% (mol). The anionic component is only oxygen O.

[ production of glass ]

Orthophosphoric acid, metaphosphate, oxide, hydroxide, carbonate, and nitrate corresponding to the constituent components of the glass were prepared as raw materials, and the raw materials were weighed and blended so that the glass compositions of the obtained glasses would be the compositions shown in table C, and the raw materials were thoroughly mixed. The obtained raw materials (batch materials) are put into a platinum crucible and heated at 1050 to 1250 ℃ for 2 to 3 hours to prepare molten glass. The molten glass is stirred for homogenization and, after fining, is cast into a mold preheated to an appropriate temperature. The glass after casting was subjected to a heat treatment at around the glass transition temperature Tg for about 1 hour, and naturally cooled to room temperature in a furnace, thereby obtaining an amorphous glass sample.

[ confirmation of glass composition ]

The contents of the glass components in the obtained amorphous glass samples were measured by inductively coupled plasma emission spectrometry (ICP-AES), and it was confirmed that the compositions were consistent with those shown in table C.

[ glass transition temperature Tg ]

The glass transition temperature Tg of the obtained amorphous glass sample was measured. The Tg was measured at a temperature increase rate of 10 ℃ per minute using a differential scanning calorimetry analyzer (DSC8270) manufactured by Rigaku corporation, and was 561 ℃.

[ volume resistivity, surface resistivity ]

The amorphous glass sample obtained was measured for volume resistivity and surface resistivity. A measuring device: Hiresta-UX MCP-800 manufactured by Mitsubishi Chemical Analytich, measurement conditions: the measurement was performed at a voltage of 500V using a volume resistance mode and a surface resistance mode.

[ crystallization ]

The obtained amorphous glass sample was crystallized to obtain a crystallized glass sample.

Volume resistivity was measured for the crystallized glass samples.

[ Hydrogen reduction treatment ]

The crystallized glass obtained was subjected to a heat treatment (hydrogen reduction treatment) at 430 ℃ for 4 hours in a reducing atmosphere using a hydrogen-containing gas, to obtain a crystallized glass sample subjected to the hydrogen reduction treatment.

The crystallized glass sample subjected to the hydrogen reduction treatment was measured for volume resistivity. It was confirmed that the volume resistivity of the crystallized glass sample subjected to the hydrogen reduction treatment was significantly reduced as compared with the volume resistivity of the amorphous glass sample and the crystallized glass sample not subjected to the hydrogen reduction treatment.

The crystallized glass sample subjected to hydrogen reduction treatment obtained in example 6 was blackened only on the surface of the sample. On the other hand, the crystallized glass sample III obtained in examples 1 to 4, which had the glass composition shown in Table A and had been subjected to hydrogen reduction treatment, was blackened even inside the sample.

In the glass sample of example 6, unlike examples 1 to 4, it contained Bi₂O₃As a glass component, therefore, only the surface of the sampleAnd (4) blackening.

Thus, Bi can be contained₂O₃As the glass component, only the surface of the glass or the crystallized glass is blackened by the hydrogen reduction treatment. Thus, for example, Bi may be excluded₂O₃In the glass composition of Table A, Bi is introduced₂O₃As a glass component, the surface of amorphous glass or crystallized glass is selectively blackened by hydrogen reduction treatment.

The volume resistivity of the amorphous glass and the crystallized glass blackened by the hydrogen reduction treatment is significantly lower than that before the blackening by the hydrogen reduction treatment.

However, if Bi₂O₃If the content of (b) is increased, there is a possibility that the decrease in volume resistivity due to hydrogen reduction treatment is hindered. Therefore, Bi was determined in consideration of the balance between the selective blackening (low resistance) of the sample surface and the volume resistivity of the blackened portion₂O₃The content of (A) is as follows.

From this fact, it was found that by selectively blackening the amorphous glass or the crystallized glass by the hydrogen reduction treatment, a portion having a low volume resistivity can be selectively formed in the amorphous glass or the crystallized glass. For example, by patterning a portion having a low volume resistivity, a part or the whole of a circuit can be formed of amorphous glass or crystallized glass.

Example 7

The amorphous glass i obtained in example 1-1 was held at 620 ℃ for 200 hours, and then held at 750 ℃ for 99 hours (crystallization treatment), thereby obtaining a crystallized glass. The Pt-Pd film was formed in a pattern on the surface of the crystallized glass obtained. The crystallized glass on which the Pt — Pd film was formed was subjected to a heat treatment (hydrogen reduction treatment) at 350 ℃ for 4 hours while flowing a hydrogen-containing gas (3 vol% hydrogen and 97 vol% nitrogen). After the hydrogen reduction treatment, the Pt — Pd film was removed from the surface of the crystallized glass. As shown in fig. 3, a crystallized glass was obtained which was colored in a pattern (black). The portions (for example, portions a to F in fig. 3) from which the Pt — Pd film was removed were colored more deeply than the other portions (for example, portions G in fig. 3).

The crystallized glass of FIG. 3 was measured for the resistance value of each part with a tester. The results are shown in Table 5.

[ Table 5]

Measurement interval	Resistance value
		Between AB	0.7×106Ω
Between AC	0.9×106Ω
		Between AD	2.2×106Ω
Between AE	12×106Ω
		Between AF	18×106Ω
Between AG	Over range

As is clear from table 5, the resistance values of the more deeply colored (black) portions (between AB, between AC, between AD, between AE, and between AF in fig. 3) are lower than the resistance values of the non-colored portions (between AG in fig. 3). The resistance value also changes depending on the thickness of the line in the deeper colored (blackened) portion, and the resistance value can be changed by changing the volume of the deeper colored (blackened) portion.

The Pt — Pd film described above is a catalyst film having a catalytic action. As the catalyst film, a film containing Ni, Pd, Pt, Au, and an alloy thereof may also be used. By forming a catalyst film in a pattern on the surface of the crystallized glass and performing hydrogen reduction treatment, the reaction easily proceeds in a portion in contact with the catalyst film of the crystallized glass, and the portion is more deeply colored. The resistance of the more deeply colored portions is less than the resistance of the uncolored portions.

Therefore, for example, a low-resistance portion is selectively formed in the crystallized glass, and thus the glass can be used as a circuit. The thickness of the portion of the glass having a low electric resistance may be adjusted by the glass composition and the hydrogen reduction treatment conditions.