JP2001019482A - Glass composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a glass having a high specific Young's modulus. SOLUTION: In the glass composition, ranges of the main components are specified to >=70 wt.% and <=80 wt.% of SiO2, >=3 wt.% and <=15 wt.% of Al2O3, >=3 wt.% and <=12 wt.% of Li2O, >=0.1 wt.% to <=10 wt.% of TiO2, >=1.5 wt.% and <=8 wt.% of ZrO2, >=0.2 wt.% and <=5 wt.% of P2O5, and >=2.1 wt.% and <=5 wt.% of CaO.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a glass composition, particularly a glass composition suitable for crystallized glass. More specifically, it relates to the composition of a crystallized glass magnetic disk.

[0002]

2. Description of the Related Art Conventionally, as a substrate for a magnetic disk,
Aluminum substrates and glass substrates have been put to practical use.
Among them, a glass substrate has received the most attention because of its excellent surface smoothness and mechanical strength. As such a glass substrate, a chemically strengthened glass substrate in which the surface of the glass substrate is strengthened by ion exchange, and a crystallized glass substrate in which a crystal component is precipitated on the substrate to strengthen the bond are known.

[0003]

By the way, the recent demand for the performance of the substrate is becoming stricter day by day.
In particular, there is a demand for an improvement in performance with respect to strength directly related to deflection and warpage during high-speed rotation. This can be represented by the specific elastic modulus (= Young's modulus / specific gravity) of the substrate material, and the higher the numerical value, the more desirable. Further, there is a demand for improvement in productivity while satisfying such requirements.
Therefore, an object of the present invention is to provide a composition with improved specific elastic modulus of glass and higher productivity.

[0004]

Means for Solving the Problems In order to achieve the above object, the invention described in claim 1 provides a composition range of a main component,
SiO ₂ is 70 wt% or more and 80 wt% or less, A
l ₂ O ₃ is and 15 wt% or less at 3 wt% or more, Li ₂
O is 3 wt% or more and 12 wt% or less, TiO ₂ is 0.1 wt% or more and 10 wt% or less, ZrO ₂ is 1.5 wt% or more and 8 wt% or less, and P ₂ O ₅ is 0.1 wt% or less.
2wt% or more and 5wt% or less, CaO is 2.1w
It is characterized by being at least t% and at most 5 wt%.

[0005]

Embodiments of the present invention will be described below. In the glass substrate of the embodiment according to the present invention, the composition range of the main component is such that SiO ₂ is 70 wt% or more and 80 wt% or more.
wt% or less, Al ₂ O ₃ is 3 wt% or more and 15 wt%
Hereinafter, Li ₂ O is at least 3 wt% and at most 12 wt%,
TiO ₂ not less than 0.1 wt% and not more than 10 wt%, Z
rO ₂ is not less than 1.5 wt% and not more than 8 wt%, and P ₂ O ₅
Is 0.2 wt% or more and 5 wt% or less, and CaO
It is characterized by being at least 1 wt% and at most 5 wt%.

[0006] Since SiO ₂ is a glass-forming oxide, if its composition ratio is less than 70 wt%, its melting property deteriorates and 80 w
If it exceeds t%, the glass will be in a stable state, and it will be difficult for crystals to precipitate.

[0007] Al ₂ O ₃ is a glass intermediate oxide, and is a component of aluminum borate-based crystals that are crystal phases precipitated by heat treatment. If the composition ratio is less than 3 wt%, the number of precipitated crystals is small, and strength cannot be obtained. If the composition ratio is more than 15 wt%, the melting temperature becomes high and the glass tends to be devitrified.

[0008] Li ₂ O plays a role as a flux and is a component of lithium disilicate-based crystals. If the composition ratio is less than 3 wt%, the precipitation of lithium disilicate as a crystal phase becomes insufficient. If the composition ratio exceeds 12 wt%, the lithium disilicate in the precipitated crystal phase becomes unstable and crystallization becomes difficult to control. In addition, chemical durability may be reduced and the magnetic film may be affected.
The stability in the washing process is deteriorated.

TiO ₂ is a flux and promotes crystal growth. If the composition ratio is less than 0.1 wt%, the meltability deteriorates, and the crystal growth becomes difficult. If the composition ratio exceeds 10 wt%, crystallization is rapidly promoted, the control of the crystallization state becomes difficult, and the deposited crystals become coarse. , Crystal phase heterogeneity occurs,
A fine and uniform crystal structure cannot be obtained, and a smooth surface required as a disk substrate in polishing cannot be obtained. Further, devitrification tends to occur during melt molding, and productivity is reduced.

ZrO ₂ is a glass-modified oxide and is a crystal nucleating agent for glass. In particular, it is very effective for uniformly depositing a quartz crystal over the entire glass. If the composition ratio is less than 1.5% by weight, it is difficult to form sufficient crystal nuclei, crystal grains are coarsened or crystals are heterogeneously deposited, and a fine and uniform crystal structure cannot be obtained. A smooth surface required as a substrate cannot be obtained. In addition, chemical durability and migration resistance are reduced, which may affect the magnetic film, and the stability in the polishing-cleaning process is deteriorated. Also 8wt%
If the temperature exceeds the above range, the melting temperature will be high, the glass will be easily devitrified, and the melt molding will be difficult. In addition, the precipitated crystal phase changes, making it difficult to obtain desired characteristics.

P ₂ O ₅ is a nucleating agent that functions as a flux and precipitates lithium disilicate-based crystals, and is an important component for uniformly depositing crystals throughout the glass.
If the composition ratio is less than 0.2 wt%, it is difficult to form sufficient crystal nuclei, crystal grains are coarsened or crystals are heterogeneously deposited, and it is difficult to obtain a fine and uniform crystal structure,
In polishing, a smooth surface required as a disk substrate cannot be obtained. Further, the effect as a flux for the hardly-fusible ZrO ₂ component cannot be obtained. If it exceeds 5% by weight, the reactivity with the furnace agent at the time of melting increases, and the devitrification also increases, so that the productivity at the time of melt molding decreases. In addition, the chemical durability may be reduced, which may affect the magnetic film, and the stability in the polishing-cleaning process may be deteriorated.

CaO acts as a flux and has a high melting property and a stable crystal phase. Composition ratio is 2.1wt
%, The meltability is not sufficiently improved. 5wt
%, The glass becomes stable and crystallization is suppressed,
It becomes difficult to obtain the required strength.

Hereinafter, the manufacturing method will be described. Raw materials including the composition of the main components of the finally produced glass substrate are sufficiently mixed at a predetermined ratio, and the mixture is put into a platinum crucible and melted. After melting, it is poured into a mold to form a rough shape. This is annealed to room temperature. Subsequently, the temperature is maintained at the indicated primary heat treatment temperature and primary treatment time (heat treatment), and crystal nucleation is performed. Subsequently, the crystal nucleus is grown while maintaining the temperature at the secondary heat treatment and the secondary treatment time. By cooling this, the desired crystallized glass is obtained.

The glass substrate obtained by the above-described manufacturing method has a SiO ₂ content of 70 wt% or more and 80 wt% or less, an Al ₂ O 3 content of ₃ wt% or more and 15 wt% or less,
i ₂ O is 3 wt% or more and 12 wt% or less, TiO ₂ is 0.1 wt% or more and 10 wt% or less, ZrO ₂ is 1.5 wt% or more and 8 wt% or less, and P ₂ O ₅ is 0.2 wt% or less.
not less than 5 wt% and not more than 5 wt%, and 2.1 wt% of CaO
As described above, it is possible to obtain a very high specific elastic modulus and a high productivity by setting the content to 5 wt% or less.

[0015]

Next, a specific example of the embodiment will be described. Material composition ratio (unit: wt%), melting temperature and melting time, primary heat treatment temperature and primary treatment time, secondary heat treatment temperature and secondary treatment time, main precipitation constituting the glasses of the first to fourth embodiments Table 1 shows the crystal phase, sub-precipitated crystal phase, average crystal grain size, specific gravity, Young's modulus, and specific elastic modulus. Table 2 similarly shows the glasses of the fifth to eighth examples. Table 3 similarly shows the ninth to twelfth examples. Table 4 similarly shows glasses of the thirteenth to sixteenth examples. Table 5 similarly shows glasses of the seventeenth to twentieth examples. Table 6 similarly shows the glass of the 21st example.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

[Table 3]

[0019]

[Table 4]

[0020]

[Table 5]

[0021]

[Table 6]

The glass composition of the first embodiment is as follows: 74.6 wt% of SiO ₂ , 6.5 wt% of Al ₂ O ₃ , 8.5 wt% of Li ₂ O, 0.5 wt% of TiO ₂ , ZrO ₂ 3.
5 wt%, P ₂ O ₅ 1.5 wt%, CaO 2.9 wt
%, K ₂ O is 1.5 wt%, and Sb ₂ O ₃ is 0.5 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1480 ° C., the melting time is 2.5 hours, the primary processing temperature is 585 ° C., the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of the treatment at 700 degrees and the secondary treatment time of 3 hours, the main precipitated crystal phase was lithium disilicate,
A glass substrate was obtained in which the by-precipitated crystal phase was quartz and the specific elastic modulus was 37.6. The above composition has not only a high specific modulus, but also a very high productivity.

The basic composition is Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since K ₂ O serving as a flux is added in addition to CaO, stability during production is improved. However, if the composition ratio is less than 0.1% by weight, sufficient melting property cannot be improved. If the content exceeds 5 wt%, the glass becomes stable, crystallization is suppressed, the chemical durability is reduced, the magnetic film may be affected, and the stability in the polishing-cleaning step is deteriorated.

Further, since Sb ₂ O ₃ serving as a fining agent is added, stability during production is improved. However, if the composition ratio is less than 0.1 wt%, a sufficient fining effect cannot be obtained, and the productivity is reduced. If it exceeds 5 wt%, the crystallization of the glass becomes unstable and the control of the precipitated crystal phase becomes impossible, so that it becomes difficult to obtain the required characteristics.

The glass composition of the second embodiment is such that 76 wt% of SiO ₂ , 7.8 wt% of Al ₂ O _3, and 8.8 wt% of Li ₂ O.
5 wt%, TiO ₂ 0.5 wt%, ZrO ₂ 3.5 w
The composition ratio of t%, P ₂ O ₅ is 1.5 wt%, and CaO is 2.2 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1460 ° C., the melting time is 2.5 hours, the primary processing temperature is 585 ° C., the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of treatment at 690 ° C. and a secondary treatment time of 2.5 hours, a glass substrate having a characteristic that the main precipitated crystal phase was lithium disilicate and the sub-precipitated crystal phase was quartz and the specific elastic modulus was 38.5 was obtained. . The above composition has not only a high specific modulus, but also a very high productivity.

The glass composition of the third embodiment is as follows: 72% by weight of SiO ₂ , 8.5% by weight of Al ₂ O _3, and 8% by weight of Li ₂ O.
t%, TiO ₂ 2 wt%, ZrO ₂ 3 wt%, P ₂ O ₅
Is 2.5 wt% and CaO is 4 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1460 ° C, the melting time is 2.5 hours, the primary processing temperature is 580 ° C, the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of the treatment at 700 ° C. and the secondary treatment time of 3 hours, a glass substrate having a characteristic that the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 38.0 was obtained. The above composition has not only a high specific modulus, but also a very high productivity.

The glass composition of the fourth embodiment is as follows: 72% by weight of SiO ₂ , 7% by weight of Al ₂ O ₃ , and 6.7% by weight of Li ₂ O.
t%, TiO ₂ 0.5 wt%, ZrO ₂ 3.5 wt
%, P ₂ O ₅ at 2.3 wt%, CaO at 4 wt%, K ₂ O
Is a composition ratio of 4 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1480 degrees, the melting time is 2.5 hours, the primary processing temperature is 580 degrees, the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of treatment at 700 ° C. for a secondary treatment time of 3 hours, a glass substrate was obtained in which the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 36.7. The above composition has not only a high specific modulus, but also a very high productivity.

The basic composition is Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since K ₂ O serving as a flux is added in addition to CaO, stability during production is improved. However, if the composition ratio is less than 0.1% by weight, sufficient melting property cannot be improved. If the content exceeds 5 wt%, the glass becomes stable, crystallization is suppressed, the chemical durability is reduced, the magnetic film may be affected, and the stability in the polishing-cleaning step is deteriorated.

The glass composition of the fifth embodiment is as follows: 74 wt% of SiO ₂ , 6 wt% of Al ₂ O ₃ , and 8 wt% of Li ₂ O
%, TiO ₂ 1.5 wt%, ZrO ₂ 5 wt%, P ₂
The composition ratio of O ₅ is 2.5 wt%, CaO is 2.5 wt%, and K ₂ O is 0.5 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1480 ° C., the melting time is 2.5 hours, the primary processing temperature is 580 ° C., the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of treatment at 700 ° C. for a secondary treatment time of 3 hours, a glass substrate was obtained in which the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 36.3. The above composition has not only a high specific modulus, but also a very high productivity.

As the composition, the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since K ₂ O serving as a flux is added in addition to CaO, stability during production is improved. However, if the composition ratio is less than 0.1% by weight, sufficient melting property cannot be improved. If the content exceeds 5 wt%, the glass becomes stable, crystallization is suppressed, the chemical durability is reduced, the magnetic film may be affected, and the stability in the polishing-cleaning step is deteriorated.

The glass composition of the sixth embodiment is as follows: 72% by weight of SiO ₂ , 9% by weight of Al ₂ O _3, and 6.5% of Li ₂ O.
t%, TiO ₂ 0.5 wt%, ZrO ₂ 3.5 wt
%, P ₂ O ₅ at 1.5 wt%, CaO at _4.5 wt%, S
The composition ratio of b ₂ O ₃ is 2.5 wt%.

The raw materials are prepared so as to contain the above composition ratio, and the melting temperature is 1,520 degrees, the melting time is 1.75 hours, the primary processing temperature is 585 degrees, the primary processing time is 5, according to the above-mentioned manufacturing method.
Time, the secondary treatment temperature was 700 ° C., and the secondary treatment time was 3 hours. As a result, the glass substrate whose main precipitated crystal phase was quartz, the secondary precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 34.5 was obtained. was gotten. The above composition has not only a high specific modulus, but also a very high productivity.

As the composition, the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since Sb ₂ O ₃ acting as a fining agent is added in addition to CaO, stability during production is improved. However, if the composition ratio is less than 0.1 wt%, a sufficient fining effect cannot be obtained, and the productivity is reduced. If it exceeds 5 wt%, the crystallization of the glass becomes unstable and the control of the precipitated crystal phase becomes impossible, so that it becomes difficult to obtain the required characteristics.

The glass composition of the seventh embodiment is such that SiO ₂ is 72 wt%, Al ₂ O ₃ is 12 wt%, and Li ₂ O is 6 wt%.
%, TiO ₂ 1 wt%, ZrO ₂ 1.5 wt%, P ₂
O ₅ of 0.5 wt%, 2.2 wt% of CaO, Sb ₂ O ₃
Is a composition ratio of 4.8 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1520 degrees, the melting time is 1.75 hours, the primary processing temperature is 600 degrees, the primary processing time is 4.5 hours, and the secondary processing time is according to the above-mentioned manufacturing method. As a result of treatment at a treatment temperature of 700 ° C. and a secondary treatment time of 3 hours, the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 33.
A glass substrate having a characteristic of 8 was obtained. The above composition has not only a high specific modulus, but also a very high productivity.

The composition is the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since Sb ₂ O ₃ acting as a fining agent is added in addition to CaO, stability during production is improved. However, if the composition ratio is less than 0.1 wt%, a sufficient fining effect cannot be obtained, and the productivity is reduced. If it exceeds 5 wt%, the crystallization of the glass becomes unstable and the control of the precipitated crystal phase becomes impossible, so that it becomes difficult to obtain the required characteristics.

The glass composition of the eighth embodiment is as follows: 78% by weight of SiO ₂ , 6.5% by weight of Al ₂ O _3, and 6% by weight of Li ₂ O.
t%, TiO ₂ 0.5 wt%, ZrO ₂ 2 wt%, P
₂ O ₅ to 1 wt%, 2.5 wt% of CaO, B ₂ O ₃ to 3.
The composition ratio is 5 wt%.

The raw materials are prepared so as to contain the above composition ratio, and the melting temperature is 1460 ° C., the melting time is 2.5 hours, the primary processing temperature is 585 ° C., the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of treatment at 690 ° C. and a secondary treatment time of 2.5 hours, a glass substrate was obtained in which the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 39.2. . The above composition has not only a high specific modulus, but also a very high productivity.

The composition is the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since B ₂ O ₃ serving as a former is added in addition to CaO, the phase separation of the glass is promoted, and the crystal precipitation and growth are promoted. However, if the composition ratio is less than 0.1% by weight, sufficient melting property cannot be improved. If it exceeds 15% by weight, the glass tends to be devitrified and molding becomes difficult, and the crystals become coarse and fine crystals cannot be obtained.

The glass composition of the ninth embodiment was such that SiO ₂ was 73.5 wt%, Al ₂ O ₃ was 6 wt%, and Li ₂ O was 7 w%.
t%, TiO ₂ 1 wt%, ZrO ₂ 2.5 wt%, P
The composition ratio is 0.5 wt% of ₂ O ₅ , 2.5 wt% of CaO, and 7 wt% of B ₂ O ₃ .

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1460 degrees, the melting time is 2.5 hours, the primary processing temperature is 600 degrees, the primary processing time is 4.
As a result of treatment for 5 hours at a secondary treatment temperature of 700 ° C. and a secondary treatment time of 3 hours, a glass having a main precipitated crystal phase of quartz, a sub-precipitated crystal phase of lithium disilicate, and a specific elastic modulus of 39.6 was obtained. A substrate was obtained. The above composition has not only a high specific modulus, but also a very high productivity.

As the composition, the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since B ₂ O ₃ serving as a former is added in addition to CaO, the phase separation of the glass is promoted, and the crystal precipitation and growth are promoted. However, if the composition ratio is less than 0.1% by weight, sufficient melting property cannot be improved. If it exceeds 15% by weight, the glass tends to be devitrified and molding becomes difficult, and the crystals become coarse and fine crystals cannot be obtained.

The glass composition of the tenth embodiment was SiO ₂
75 wt%, Al ₂ O ₃ 6.5 wt%, Li ₂ O 6.5 wt%, TiO ₂ 0.5 wt%, ZrO ₂ 3.
5wt%, 1.3wt% of P ₂ O _5, 2.7wt the CaO
% And MgO at 4 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1480 ° C., the melting time is 2.5 hours, the primary processing temperature is 585 ° C., the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of treatment at 690 ° C. and a secondary treatment time of 2.5 hours, a glass substrate was obtained in which the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 37.7. . The above composition has not only a high specific modulus, but also a very high productivity.

The composition is the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since MgO serving as a flux is added in addition to CaO, granular quartz crystals, which are one of the crystal phases, are aggregated to form crystal particle masses. However, if the composition ratio is less than 0.1 wt%, the working temperature range becomes narrow, and the chemical durability of the glass matrix phase does not improve. If it exceeds 12% by weight, it is difficult to obtain the required strength due to precipitation of another crystal phase.

The glass composition of the eleventh embodiment was SiO ₂
72 wt%, Al ₂ O ₃ 8 wt%, and Li ₂ O 6.5.
wt%, the TiO ₂ 1.2 wt%, a ZrO ₂ 4.2 wt
%, P ₂ O ₅ 2.8 wt%, CaO _4.5 wt%, M
gO has a composition ratio of 0.8 wt%.

The raw materials are prepared so as to contain the above composition ratio, and the melting temperature is 1480 ° C., the melting time is 2.5 hours, the primary processing temperature is 580 ° C., the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of the treatment at 700 ° C. and the secondary treatment time of 3 hours, a glass substrate having a characteristic that the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 36.6 was obtained. The above composition has not only a high specific modulus, but also a very high productivity.

The composition is the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since MgO serving as a flux is added in addition to CaO, granular quartz crystals, which are one of the crystal phases, are aggregated to form crystal particle masses. However, if the composition ratio is less than 0.1 wt%, the working temperature range becomes narrow, and the chemical durability of the glass matrix phase does not improve. If it exceeds 12% by weight, it is difficult to obtain the required strength due to precipitation of another crystal phase.

The glass composition of the twelfth embodiment was SiO ₂
74 wt%, Al ₂ O ₃ 6.5 wt%, Li ₂ O 8.5 wt%, TiO ₂ 0.5 wt%, ZrO ₂ 3.
5wt%, 1.5wt% of P ₂ O _5, 1.5wt the CaO
% And BaO at 2.8 wt%.

The raw materials were prepared so as to contain the above composition ratio, and the melting temperature was 1,520 ° C., the melting time was 1.75 hours, the primary processing temperature was 585 ° C., and the primary processing time was 5, according to the above-mentioned manufacturing method.
Time, the secondary treatment temperature was 700 ° C., and the secondary treatment time was 3 hours. As a result, a glass substrate having a characteristic that the main precipitated crystal phase is lithium disilicate, the sub-precipitated crystal phase is quartz, and the specific elastic modulus is 34.7 is obtained. was gotten. The above composition has not only a high specific modulus, but also a very high productivity.

As the composition, the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since BaO serving as a flux is added in addition to CaO, stability during production is improved. However, if the composition ratio is less than 0.1% by weight, sufficient melting property cannot be improved. If it exceeds 5% by weight, the glass becomes stable, crystallization is suppressed, and it becomes difficult to obtain the required strength.

The glass composition of the thirteenth embodiment was SiO ₂
The 74 wt%, 8 wt% of Al ₂ O _3, the Li ₂ O 8.2
wt%, the TiO ₂ 4 wt%, a ZrO ₂ 1.8 wt%,
0.3 wt% of P ₂ O ₅ , 2.5 wt% of CaO, BaO
Is a composition ratio of 1.2 wt%.

The raw materials were prepared so as to have the above composition ratio, and the melting temperature was 1480 ° C., the melting time was 2.5 hours, the primary processing temperature was 600 ° C., and the primary processing time was 4.
As a result of treatment for 5 hours at a secondary treatment temperature of 700 ° C. and a secondary treatment time of 3 hours, a glass having a main precipitated crystal phase of lithium disilicate, a sub-precipitated crystal phase of quartz, and a specific elastic modulus of 37.2 is obtained. A substrate was obtained. The above composition has not only a high specific modulus, but also a very high productivity.

As the composition, the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since BaO serving as a flux is added in addition to CaO, stability during production is improved. However, if the composition ratio is less than 0.1% by weight, sufficient melting property cannot be improved. If it exceeds 5% by weight, the glass becomes stable, crystallization is suppressed, and it becomes difficult to obtain the required strength.

The glass composition of the fourteenth embodiment was SiO ₂
The 75wt%, Al ₂ O ₃ and 6.5 wt%, the Li ₂ O 8
wt%, the TiO ₂ 0.5 wt%, a ZrO ₂ 3.5 wt
%, P ₂ O ₅ 1.5 wt%, CaO 2.8 wt%, Z
nO has a composition ratio of 2.2 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1480 ° C., the melting time is 2.5 hours, the primary processing temperature is 585 ° C., the primary processing time is 5 hours, and the secondary processing temperature is according to the above-mentioned manufacturing method. As a result of treatment at 690 ° C. and a secondary treatment time of 2.5 hours, a glass substrate was obtained in which the main precipitated crystal phase was quartz, the secondary precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 37.2. . The above composition has not only a high specific modulus, but also a very high productivity.

As the composition, the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Uniform crystal precipitation is assisted because ZnO that acts as a flux is added in addition to CaO. However, when the composition ratio is 0.1
If the amount is less than wt%, sufficient improvement in crystal homogenization cannot be achieved. If it exceeds 5% by weight, the glass becomes stable, crystallization is suppressed, and it becomes difficult to obtain the required strength.

The glass composition of the fifteenth embodiment was SiO ₂
74.5 wt%, Al ₂ O ₃ 7 wt%, Li ₂ O 6.5 wt%, TiO ₂ 1 wt%, ZrO ₂ 3.5 w
t%, P ₂ O ₅ 1 wt%, CaO 2.5 wt%, Zn
O has a composition ratio of 4 wt%.

The raw materials were prepared so as to contain the above composition ratio, and the melting temperature was 1500 ° C., the melting time was 1.75 hours, the primary processing temperature was 585 ° C., and the primary processing time was 5 in accordance with the above-mentioned manufacturing method.
Time, the secondary processing temperature was 700 ° C., and the secondary processing time was 3 hours. As a result, the glass substrate was characterized in that the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 36.1. was gotten. The above composition has not only a high specific modulus, but also a very high productivity.

As the composition, the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Uniform crystal precipitation is assisted because ZnO that acts as a flux is added in addition to CaO. However, when the composition ratio is 0.1
If the amount is less than wt%, sufficient improvement in crystal homogenization cannot be achieved. If it exceeds 5% by weight, the glass becomes stable, crystallization is suppressed, and it becomes difficult to obtain the required strength.

The glass composition of the sixteenth embodiment was SiO ₂
The 74.6wt%, 8wt% of Al ₂ O _3, 8.5wt% of Li ₂ O, the TiO ₂ 0.5 wt%, a ZrO ₂ 3.
5 wt%, P ₂ O ₅ 1.5 wt%, CaO 2.9 wt
% And Nb ₂ O ₅ in a composition ratio of 0.5 wt%.

The raw materials are prepared so as to have the above composition ratio, and the melting temperature is 1480 ° C., the melting time is 2.5 hours, the primary processing temperature is 585 ° C., the primary processing time is 5 hours, and the secondary processing temperature is in accordance with the above-mentioned manufacturing method. As a result of the treatment at 700 degrees and the secondary treatment time of 3 hours, the main precipitated crystal phase was lithium disilicate,
A glass substrate having a crystal having a sub-precipitated crystal phase and a specific elastic modulus of 38.1 was obtained. The above composition has not only a high specific modulus, but also a very high productivity.

The composition is the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since Nb ₂ O ₅ acting as a flux is added in addition to CaO, the nucleating agent substance increases. However, if the composition ratio is less than 0.1 wt%, the rigidity cannot be sufficiently improved. If the content exceeds 5 wt%, crystallization of the glass becomes unstable, the crystal phase to be precipitated cannot be controlled, and it becomes difficult to obtain desired characteristics.

The glass composition of the seventeenth embodiment was SiO ₂
74.8 wt%, Al ₂ O ₃ 6.5 wt%, Li ₂ O
The 7.5 wt%, the TiO ₂ 0.5 wt%, a ZrO ₂ 3.5wt%, 1.5wt% of P ₂ O _5, a CaO 2.7
wt%, a 3 wt% of the composition ratio of the Nb ₂ O _5.

The raw materials are prepared so as to have the above composition ratio, and according to the above-mentioned production method, the melting temperature is 1500 ° C. and the melting time is 2 hours.
Time, primary processing temperature 585 degrees, primary processing time 5 hours, 2
As a result of the treatment at the next treatment temperature of 700 ° C. and the second treatment time of 3 hours, a glass substrate was obtained in which the main precipitated crystal phase was quartz, the sub-precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 35.7. Was. The above composition has not only a high specific modulus, but also a very high productivity.

The composition is the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since Nb ₂ O ₅ acting as a flux is added in addition to CaO, the nucleating agent substance increases. However, if the composition ratio is less than 0.1 wt%, the rigidity cannot be sufficiently improved. If the content exceeds 5 wt%, crystallization of the glass becomes unstable, the crystal phase to be precipitated cannot be controlled, and it becomes difficult to obtain desired characteristics.

The glass composition of the eighteenth embodiment was SiO ₂
74.8 wt%, Al ₂ O ₃ 6.5 wt%, Li ₂ O
The 8.5 wt%, the TiO ₂ 1.5 wt%, a ZrO ₂ 3.5wt%, 1.5wt% of P ₂ O _5, a CaO 2.7
wt% and Ta ₂ O ₅ are 1 wt%.

The raw materials were prepared so as to have the above composition ratio, and according to the above-mentioned production method, the melting temperature was 1500 ° C. and the melting time was 2 hours.
Time, primary processing temperature 585 degrees, primary processing time 5 hours, 2
As a result of the treatment at the next treatment temperature of 700 ° C. and the second treatment time of 3 hours, a glass substrate was obtained in which the main precipitated crystal phase was lithium disilicate, the sub-precipitated crystal phase was quartz, and the specific elastic modulus was 36.2. Was. The above composition has not only a high specific modulus, but also a very high productivity.

As the composition, the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since Ta ₂ O ₅ serving as a flux is added in addition to CaO, the meltability and strength are improved, and the chemical durability of the glass matrix phase is improved. However, when the composition ratio is 0.1
If the amount is less than wt%, the rigidity cannot be sufficiently improved. 5
If the content exceeds wt%, the crystallization of the glass becomes unstable, the control of the precipitated crystal phase becomes impossible, and it becomes difficult to obtain the required characteristics.

The glass composition of the nineteenth embodiment was SiO ₂
The 75 wt%, 6.5 wt% of Al ₂ O _3, 8.5wt% of Li ₂ O, the TiO ₂ 0.5 wt%, a ZrO ₂ 1.
5wt%, 1.5wt% of P ₂ O _5, 2.5wt the CaO
%, Ta ₂ O ₅ is 4 wt%.

The raw materials were prepared so as to have the above composition ratio, and the melting temperature was 1540 ° C., the melting time was 1.75 hours, the primary processing temperature was 585 ° C., and the primary processing time was 5 in accordance with the above-mentioned manufacturing method.
Treatment time was 690 ° C., secondary treatment temperature was 690 ° C., and secondary treatment time was 2.5 hours. As a result, the main precipitated crystal phase was quartz, the secondary precipitated crystal phase was lithium disilicate, and the specific elastic modulus was 32.8.
Thus, a glass substrate having such characteristics was obtained. The above composition has not only a high specific modulus, but also a very high productivity.

The composition is Si, which is a basic composition.
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since Ta ₂ O ₅ serving as a flux is added in addition to CaO, the meltability and strength are improved, and the chemical durability of the glass matrix phase is improved. However, when the composition ratio is 0.1
If the amount is less than wt%, the rigidity cannot be sufficiently improved. 5
If the content exceeds wt%, the crystallization of the glass becomes unstable, the control of the precipitated crystal phase becomes impossible, and it becomes difficult to obtain the required characteristics.

The glass composition of the twentieth embodiment was SiO ₂
75.2 wt%, Al ₂ O ₃ 6.5 wt%, Li ₂ O
The 8.5 wt%, the TiO ₂ 1.7 wt%, a ZrO ₂ 3.5wt%, 1.5wt% of P ₂ O _5, a CaO 2.3
wt% and La ₂ O ₃ in a composition ratio of 0.8 wt%.

The raw materials were prepared so as to contain the above composition ratio, and the melting temperature was 1480 ° C., the melting time was 2.5 hours, the primary processing temperature was 585 ° C., the primary processing time was 5 hours, and the secondary processing temperature was in accordance with the above-mentioned manufacturing method. As a result of treatment at 690 ° C. and a secondary treatment time of 2.5 hours, a glass substrate having a characteristic that the main precipitated crystal phase is lithium disilicate and the sub-precipitated crystal phase is quartz and the specific elastic modulus is 37.1 was obtained. . The above composition has not only a high specific modulus, but also a very high productivity.

The basic composition is Si.
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since La ₂ O ₃ serving as a flux is added in addition to CaO, crystal precipitation is suppressed. However, the composition ratio is 0.1w
If it is less than t%, the rigidity cannot be sufficiently improved. 5w
If the content exceeds t%, crystallization of the glass becomes unstable, the crystal phase to be precipitated cannot be controlled, and it becomes difficult to obtain desired characteristics.

The glass composition of the twenty-first embodiment was SiO ₂
74.6 wt%, Al ₂ O ₃ 6.5 wt%, Li ₂ O
The 8.5 wt%, the TiO ₂ 0.5 wt%, a ZrO ₂ 3.5wt%, 0.7wt% of P ₂ O _5, a CaO 2.2
wt% and La ₂ O ₃ at 3.5 wt%.

The raw materials were prepared so as to contain the above composition ratio, and the melting temperature was 1540 ° C., the melting time was 1.75 hours, the primary processing temperature was 600 ° C., the primary processing time was 4.5 hours, As a result of treatment at a treatment temperature of 700 ° C. and a secondary treatment time of 3 hours, the main precipitated crystal phase was lithium disilicate, the sub-precipitated crystal phase was quartz, and the specific elastic modulus was 34.
A glass substrate having a characteristic of 0 was obtained. The above composition has not only a high specific modulus, but also a very high productivity.

The composition is the basic composition of Si
O ₂ , Al ₂ O ₃ , Li ₂ O, TiO ₂ , ZrO ₂ , P ₂ O ₅ ,
Since La ₂ O ₃ serving as a flux is added in addition to CaO, crystal precipitation is suppressed. However, the composition ratio is 0.1w
If it is less than t%, the rigidity cannot be sufficiently improved. 5w
If the content exceeds t%, crystallization of the glass becomes unstable, the crystal phase to be precipitated cannot be controlled, and it becomes difficult to obtain desired characteristics.

[0084]

According to the present invention, a glass substrate having a specific elastic modulus of 30 or more and high productivity can be obtained.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Hiroshi Yugame 2-3-13 Azuchicho, Chuo-ku, Osaka City Osaka International Building Minolta Co., Ltd. (72) Kazuhiko Ishimaru 2-3-3 Azuchicho, Chuo-ku, Osaka-shi No. 13 Osaka International Building Minolta Co., Ltd. F-term (reference) 4G062 AA11 BB01 BB09 DA07 DB03 DB04 DC01 DD02 DD03 DE01 DF01 EA03 EA04 EB01 EC01 ED01 EE03 EF01 EG01 FA01 FB02 FB03 FC03 FD01 FE01 FF01 GA01 GD01 GE01 HH01 HH03 HH05 HH07 HH09 HH11 HH13 HH15 HH17 HH20 JJ01 JJ03 JJ05 JJ07 JJ10 KK01 KK03 KK05 KK07 KK10 MM27 NN33 QQ02 QQ06 5D006 CB04 CB07 DA03 FA00

Claims (1)

[Claims] The method according to claim 1 The composition range of the main component, SiO ₂ is 70w
and 80 wt% in t% more or less, Al ₂ O ₃ is and 15 wt% or less at 3 wt% or more, Li ₂ O is less and 12 wt% at 3 wt% or more and less 10 wt% in TiO ₂ is more than 0.1 wt%, ZrO ₂ is 1.5 wt% or more and 8 wt% or less, P ₂ O ₅ is 0.2 wt% or more and 5 wt% or less, CaO is 2.1 wt% or more and 5 wt% or less. Glass composition.