TWI279396B - Substrate glass for display device - Google Patents

Abstract

A substrate glass for a flat panel display device, which comprises, in wt%, 63 to 69% of SiO2, 0.5 to 5% of Al2O3, 2 to 7% of Na2O, 8 to 17% of K2O, 10 to 18% of MgO, 0 to 7% of CaO, 0 to 3% of SrO, 0 to 3% of BaO and 0.5 to 7% of ZrO2, and has a distortion spot of 570 DEG C or higher.

Description

1279396 (1) Description of the Invention [Technical Field of the Invention] The present invention relates to a glass composition excellent in heat resistance, light weight, and high strength. In particular, it is suitable for glass substrates that require the same high thermal expansion coefficient and high heat resistance as ordinary soda strontium glass, such as PDP (plasma display panel), EL (electrically excited light), FE (cold hair color display), etc. The glass composition of the substrate for electronic display. [Prior Art] Conventionally, in the field of PDP manufacturing, the substrate glass is used at a normal temperature of ~3 ° C. The coefficient of thermal expansion is 80 to 90 X 1 (T7 / ° C degree, the deformation point is 5 1 0 to 5 2 0 ° C-level sodium-calcium bismuth glass. Sodium-calcium strontium glass is used in many aspects to have a low price and easy to adjust. However, due to the low deformation point, the electrode line pattern placed on the glass substrate is lower than the melting point. When the glass is formed into an insulating coating or the like, and the various heat treatments are applied to the panel, the substrate glass is likely to be deformed by bending or shrinkage. In order to eliminate the above-mentioned discomfort, the soda-lime glass similar to the soda-lime-glass glass has been proposed in recent years. A glass having a thermal expansion coefficient similar to that of sodium calcium strontium glass, a deformation point of more than 550 ° C, or a high deformation point glass exceeding 600 ° C (for example, Patent Documents 1 to 3). These glasses are used in the manufacture of display panels. In the step, the thermal deformation is small, and the integration with other members is also good. Patent Document 1: Japanese Patent No. 273 8 03 6 Patent Document 2: Japanese Patent Laid-Open No. 9-20264 No. 1 Patent Document 1: Japanese Special Opening 9-25 5 3 54 (2) 1279396 [Disclosure of the Invention] [Revelation of the Invention] However, the high-deformation glass of the past has a composition which is slightly specific to the sodium calcium silicate glass, and the density of the high-deformation point glass is higher than that of the sodium calcium strontium. The glass is heavy, and most of them exceed 2.6. This is a problem that the weight of the display device is difficult to be sag due to the weight of the glass substrate. That is, the amount of self-weight (W) of the glass substrate is as shown in the formula (1). Since the glass substrate increases in density (P), the amount of sag is greatly changed when the glass substrate is enlarged, and discomfort such as breakage occurs in the transportation or moving step of the substrate. W = c ( p / E) (L4 / t2) (1) W: maximum sinking amount, L: distance between 2 side supports, t: plate thickness, P: glass density, E: Young's modulus of glass, c: coefficient, due to the high deformation glass that is more than sodium calcium The glass is brittle and has a problem of easy cracking when applied to various treatments. Generally, the crack of the glass is brittle fracture caused by the flaw (crack), and the resistance to the damage is called fracture toughness (KIC). Therefore, it is necessary to improve the above cracking problem. - KIC-high glass. The object of the present invention is to provide a substrate glass having the same linear expansion coefficient as that of soda-lime-germ glass and a low deformation point and KIC high density.

According to the present invention, it can be provided in % by weight, 'containing Si〇2 is 63 to 69, Al2〇3 is 〇·5~5, Na20 is 2 to 7, K20 is 8 to 17, MgO 1279396

The substrate glass for a flat display device having 10 to 18, CaO of 0 to 7, SrO of 0 to 3, BaO of 0 to 3, Zr〇2 of 0.5 to 7, and a deformation point of 570 ° C or more. BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, it is possible to provide a high-deformation point glass having the same degree of expansion coefficient as that of ordinary soda-lime glass, low density, and high KIC resistance, and φ is extremely suitable for PDP, EL and A glass substrate for an electronic display such as FED. The glass according to the present invention is substantially expressed by weight %, and may contain only SiO 2 of 63 to 69, A1203 of 0.5 to 5, Na20 of 2 to 7, K2 〇 of 8 to 17, MgO of 10 to 18, and CaO. A glass composed of 0 to 7, SrO of 0 to 3, BaO of 0 to 3, and Zr02 of 0.5 to 7.

Si02 is a glass main component, and when the weight % is less than 63%, the desired fracture toughness KIC cannot be obtained, and the heat resistance and chemical durability of the glass are deteriorated. On the other hand, when it exceeds 69%, since the high-temperature viscosity of the glass melt becomes high, the glass forming becomes difficult. Further, the coefficient of thermal expansion of the glass is too small, and the integration with other members of the display panel is deteriorated. Therefore, it is 63 to 69%, and is ideally in the range of 64 to 68%. ^ ai2o3 is a necessary component for improving the deformation point and breaking the toughness KIC. When the weight % is less than 0.5%, the deformation point and fracture toughness K1C of the glass become lower, and on the other hand, it exceeds 5 °/. At the time, since the high-temperature viscosity of the glass melt becomes high, the tendency of the transparent disappearance tends to increase the difficulty in forming the glass. Therefore, 〇.5~5 %, ideally 1~4%.

Both Na2◦ and K20 are the melt action of glass melting, and it is indispensable to maintain the linear thermal expansion coefficient of (4) 1279396 moderate glass. Less than 2°/. The effect as a melt is insufficient and the coefficient of linear expansion is too low. When it exceeds 7%, the deformation point is too low. Therefore, 2 to 7%, ideally 3 to 6%. K20 shows the same effect of Na20, and at the same time, it inhibits the movement of alkali ions due to the mixed alkali effect with Na20, which is a necessary component for high glass volume resistivity. When the amount is less than 8%, the effect is not sufficient. When the temperature exceeds 17%, the coefficient of linear expansion is too large, and the deformation point is too low. The content of Κ2〇 may be 14 to 17%, and may be 15 to 17%. When K20 is this content, it is defined as the first glass of the present invention. The relative Κ20 content is 8 to 15%, 8 to 14%, or 10 to 13%. When Κ20 is the content, it is defined as the second glass of the present invention.

MgO is an essential component for increasing the fracture toughness KIC of the glass and increasing the deformation point. When the amount is less than 10%, the effect is not sufficient. On the other hand, when it exceeds 18%, the tendency of transparency disappears, and the formation of glass becomes difficult. Therefore, the range is 1 0~1 8 %, ideally 1 〇 · 5~1 6 %.

CaO is not an essential component, and has a function of lowering the viscosity of the molten glass when the glass is melted, and has a function of raising the deformation point of the glass. Therefore it can contain 7°/. the following. When the hardness exceeds 7%, the hardness of the glass rises and the toughness Kic decreases, and it is preferable to introduce 7% or less.

SrO and BaO are not essential components, and coexistence with CaO has the effect of reducing the high-temperature viscosity of the glass melt to cause transparency to disappear. When the temperature exceeds 3%, the coefficient of thermal expansion of the line is high, and each of them is preferably in the range of 3% or less.

Zr〇2 is an essential component for the effect of improving the chemical stability of the glass and the chemical durability of the glass. The content of Zr〇2 is preferably 0.5 or more. When it is more than 7%, the density (5) rises to 1,279,396 degrees, and it cannot maintain the hope. Therefore, it is in the range of 0.5 to 7%, preferably 1 to 6%. ^ B2〇3 Non-essential component, because it has the effect of reducing the viscosity of molten glass and glass when the glass is melted, it has the effect of reducing the tendency of transparency to disappear, and may contain 5% or less. When the value exceeds 5%, the deformation point is too low, and it is desirable to introduce a range of 5% or less.

Li20 is an optional component that promotes lowering the high temperature viscosity of the glass and #melting of the glass material. However, when the content exceeds 3%, the deformation point is excessively lowered, and it is desirable to introduce a range of 3% or less. The exemplified glass according to the present invention may be composed only of the above-mentioned components, and other components may be contained in a weight % of not more than 3% by weight insofar as the object of the present invention is not impaired. For example, the melting, clarification, and moldability of the glass may include a total amount of S03, Cl, F, and As203 of 1% or less. Further, the color of the glass may contain Fe2〇3, CoO, NiO or the like in a total amount of 1% or less. Further, in order to prevent the PDP from browning the electron beam, it is possible to contain Ti02 and Ce02 each to 1%, and the total amount is 1%. The deformation point is less than 57 (TC, the electrode line pattern is placed on the substrate, and the insulating coating is formed by the low-melting glass. When the panel is manufactured with various heat treatments, the substrate glass is prone to deformation or shrinkage. Further, in the glass of the present invention, the average linear thermal expansion coefficient at 30 ° C to 300 ° C may be 70 X 1 (T7 ° C to 90 X 10 · 7 ° C. When this range is exceeded) The integration with other members constituting the display panel is deteriorated. Further, in the first glass of the present invention, the average linear thermal expansion coefficient at 30 ° C to 300 ° C may be 86 X 10·7 ° C to 90 ° In the range of X ΙΟ·7 t, also -8-(6) 1279396 can be in the range of 87 χ 7 '7 °C to 88 χ l〇·7 °C, and the average linear expansion coefficient is approximately the same in the latter range. Generally, the average linear thermal expansion coefficient of the soda-calcium glass produced by the floating body method is equal. In contrast, the second glass has an average linear thermal expansion coefficient of 70 X 1 at - 30 ° C to 3 ° ° C ( Γ 7 ° C to 85 X 10·7 ° C. Further, in the glass of the present invention, the fracture toughness K! c may be 0.7 Μ P a · m1/2 or more. The fracture toughness KIC is not reached. 0.7 MPa · m1/2 may show the problem of cracking easily in the manufacturing steps of the device. Moreover, the glass of the present invention may have a density of less than 2.6 g / cm 3 . When the density is 2.6 g / cm 3 or more, the ratio is higher than the average The sodium sulphate glass is large, and when the display device is enlarged, an unsuitable situation such as deformation or destruction of the glass substrate due to its own weight occurs. [Embodiment] Hereinafter, the non-limiting examples 1 to 5 and the table shown in Table 1 are shown. The first and second glasses of the present invention are exemplified by the non-® limited examples 1 to 8 shown in Fig. 2. In contrast, the comparative examples 1 to 4 shown in Table 3 are the counterparts 0 of this example (Example 1) ～5, Examples 1 to 8 and Comparative Examples 1 to 4) (Production of glass) will be composed of cerium, alumina, sodium carbonate, sodium sulfate, potassium carbonate, magnesium oxide, calcium carbonate, cesium carbonate, cesium carbonate, and cesium. The raw material prepared by the acid chromium is filled in a platinum pliers pot, and is heated in an electric furnace at 1 500 to 1 600 ° C for about 6 hours to melt (7) 1279396. The mixture is heated and melted to melt the glass with a platinum rod. Homogenization. Next, pour the molten glass into the mold and move it to a temperature of 600~700 °C for slow cooling. The furnace was cooled in the furnace to obtain glasses of the compositions shown in Examples 1 to 5 of Table 1, Examples 1 to 8 of Table 2, and Comparative Examples 1 to 4 of Table 3. The obtained glass sample was bubble-free. Or homogenous matter of the vein. These glasses are measured by the following methods for deformation point (°C), average linear thermal expansion coefficient (1 (T7 / ° C), fracture toughness KIC (MPa · m1/2) and density _ ( g / cm3). The deformation point is measured by the ray bending method based on the provisions of JIS R 3103-2. The linear expansion coefficient was measured by a mechanical analyzer TM A 8 3 1 0 (manufactured by Nippon Scientific Electric Co., Ltd.) at an average linear thermal expansion coefficient of 30 to 300 °C. The destructive system was calculated using a microhardness tester DMH-2 (manufactured by Matsushita Seiki Co., Ltd.) in accordance with the fracture toughness test method (compression press method) of the precision ceramics described in JIS R 1 607. The density is determined by the Achillemethod method using a bubble-free glass (about 5 〇 g). -10- (8) 1279396 Table 1_ Example 1 2 3 4 5

Si 〇 2 66.0 Al2 〇3 1.0 Na20 4.0 K20 15.5 MgO 11.0 CaO SrO BaO Zr 02 2.5 Deformation point 570 Density 2.491 Destructive toughness KIC 0.767 Expansion coefficient 88 64.5 64.5 64.0 63.0 2.0 3.0 3.5 4.0 4.0 4.0 3.5 5.0 15.5 15.5 16.5 14.0 11.5 10.5 10.0 10.0 0.5 0.5 1.0 2.5 2.0 2.0 3.0 573 570 572 570 2.496 2.485 2.483 2.512 0.775 0.797 0.805 0.784 86 86 87 87 -11 - (9) 1279396 Table 2_ Example 123456 78

Si 〇2 AI2 〇3 63.5 64.0 64.0 65.0 65.0 65.0 65.5 68.0 4.5 4.5 4.5 5.0

Na2 0 κ20 14.0 10.5 MgO 10.5 11.5 CaO 0.5 0.5 SrO 0.5 0.5 BaO Zr 02 2.0 3.5 Deformation point 593 606 Density 2.51 2.535 Destructive toughness KIC 0.87 0.838 Expansion coefficient 85 76 2.0 1.0 1.5 3.0 2.0 1.0 6.0 3.0 6.0 4.0 3.5 6.0 8.5 11.0 8.0 11.5 11.5 8.0 15.0 10.5 13.0 11.0 1L0 16.0 0.5 2.0 1.5 1.0 1.0 3.0 0.5 0.5 0.5 1.0 3.5 4.5 3.5 4.0 5.5 1.0 601 606 597 614 624 586 2.563 2.587 2.569 2.537 2.548 2.505 0.834 0.774 0.806 0.819 0.819 0.875 79 72 79 76 71 77 - 12- (10) 1279396 Table 3_________ Comparative Example 1 23 4

Si 〇2 70.9 54.6 55.5 68.9 Ah 〇3 2.0 8.7 6.6 0.9 Na2〇13.6 4.5 5.1 4.6 K2〇0.8 8.2 6.4 4.8 MgO 3.6 2.9 1.2 0.1 CaO 9.1 7.4 2.2 9.7 SrO 9.3 6.7 BaO 9.9 9.0 0.4 Zr O2 3.8 4.7 3.9 Deformation point 507 583 580 582 Density 2.514 2.741 2.843 2.64 Destructive toughness KIC 0.73 0.65 0.67 0.64 Expansion coefficient 87 85 83 75

(Results) The glasses of Examples 1 to 5 in Table 1 and the glasses of Examples 1 to 8 in Table 2 correspond to the first and second glasses of the present invention. Comparative Example 1 is a soda lime bismuth glass. Comparative Examples 2 to 4 are conventional high-deformation point glasses. In the sodium-calcium bismuth glass of Comparative Example 1, the density was less than 2.6, and the fracture toughness Kic was 〇·7 Mpa · m 1/2. The deformation point was significantly lower than that of Comparative Example 2 to 4 (11) Γ279396 glass. On the other hand, the 咼 deformation point glass of Comparative Examples 2 to 4 showed a deformation point of 580 ° C or more, and the density exceeded 2 · 6 and the fracture toughness c did not reach 0 · 7 Μ Pa · m 1 /2. On the other hand, in the glass of Examples 1 to 5 in Table 1 and Tables 1 to 8 in Table 2, the deformation point at a sufficiently high density of 570 ° C or higher was less than 2 · 6 ', and the fracture toughness exceeded 〇. ·75 MPa·m1/2 satisfies 0.7 MPa·m1/2 or more. Therefore, it can be understood that the glass of the present invention has the same linear thermal expansion coefficient as that of the sodium brocade glass, and has the same heat resistance as the high-deformation point glass, low density, and high fracture toughness.

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Claims (1)

1279396 ψ X. Application for Patent Fan Park No. 94 1 1 79 1 2 Patent Application Revision of Chinese Patent Application Scope Amendment of December 8, 1995 1 . A substrate glass for a flat display device, which is characterized by weight %, containing SiO 2 of 63 to 69, Α12〇3 of 0.5 to 5, Na20 of 2 to 7, K2〇 of 8 to 17, and MgO of 10 ～18, CaO is 0 to 7, 31*0 is 〇~3, 8&0 is 0 to 3, 21*02 is 0.5 to 7, and the deformation point is 570 ° C or more, and the fracture toughness KIC is 0.7 MPa. Above m1/2, the density is less than 2·6 g / cm3. 2. The substrate glass for a flat display device according to claim 1, wherein the substrate is substantially expressed by weight %, and is only 63 to 69 for SiO 2 , 0.5 to 5 for Al 2 〇 3, 2 to 7 for Na 2 , and 8 for K 20 . ~17, MgO is 10 to 18, CaO is 〇~7, Si:0 is 0 to 3, BaO is 0 to 3, and Zr02 is 0.5 to 7. 3. The substrate glass for a flat display device according to claim 1 or 2, which is Κ2 Ο 14 4 to 17% by weight. 4. The base glass for a flat display device according to claim 1 or 2, which is Κ2 Ο 8 to 15 weight. /〇. 5. The substrate glass for a flat display device according to claim 1 or 2, wherein the average linear thermal expansion coefficient at 30 ° C to 300 ° C is 70 X iO · 7 / 〇 C 〜 90 X 1 〇 · 7 /. . By. 6. The substrate glass for a flat display device according to item 3 of the patent application, wherein the average linear thermal expansion coefficient at 30 ° C to 300 ° C is 86 X 10·7 1279396 / °C ～9 Ο χ 1 (Γ7 / °C. 7. For the substrate glass for flat panel display device of claim 4, the average linear thermal expansion coefficient at 30 ° C to 300 ° C is 70 χ 10_7 / °C ~ 8 5 χ 1 0 · 7 / °C. -2-