摘要:
Disclosed are a glass substrate for an information recording medium, having excellent scratch resistance and a light weight and having high fracture toughness, the glass substrate having a fragility index value, measured in water, of 12 μm−1/2 or less or having a fragility index value, measured in an atmosphere having a dew point of −5° C. or lower, of 7 μm−1/2 or less, or the glass substrate comprising, by mol %, 40 to 75% of SiO2, 2 to 45% of B2O3 and/or Al2O3 and 0 to 40% of R′2O in which R′ is at least one member selected from the group consisting of Li, Na and K), wherein the total content of SiO2, B2O3, Al2O3 and R′2O is at least 90 mol %, and a magnetic information recording medium comprising a magnetic recording layer formed on the glass substrate.
摘要翻译:公开了一种用于信息记录介质的玻璃基板,具有优异的耐擦伤性和重量轻并且具有高断裂韧性,玻璃基板在水中测得的脆性指数值为12μm-1/2或更小,或具有 在露点为-5℃以下的气氛中测定的7μm-1/2以下的脆性指数值,或摩尔%为40〜75%的SiO 2的玻璃基板,2〜 45%的B 2 O 3和/或Al 2 O 3和0〜40%的R'2O,其中R'为选自Li,Na和K中的至少一种),其中SiO 2,B 2 O 3,Al 2 O 3和 R'2O为90摩尔%以上,磁性信息记录媒体包含形成在玻璃基板上的磁记录层。
摘要:
Disclosed are a glass substrate for an information recording medium, having excellent scratch resistance and a light weight and having high fracture toughness, the glass substrate having a fragility index value, measured in water, of 12 μm−1/2 or less or having a fragility index value, measured in an atmosphere having a dew point of −5° C. or lower, of 7 μm−1/2 or less, or the glass substrate comprising, by mol %, 40 to 75% of SiO2, 2 to 45% of B2O3 and/or Al2O3 and 0 to 40% of R′2O in which R′ is at least one member selected from the group consisting of Li, Na and K), wherein the total content of SiO2, B2O3, Al2O3 and R′2O is at least 90 mol %, and a magnetic information recording medium comprising a magnetic recording layer formed on the glass substrate.
摘要翻译:公开了一种用于信息记录介质的玻璃基板,具有优异的耐擦伤性和重量轻并且具有高断裂韧性,玻璃基板在水中测得的脆性指数值为12μm-1/2或更小,或具有 在露点为-5℃以下的气氛中测定的7μm-1/2以下的脆性指数值,或摩尔%为40〜75%的SiO 2的玻璃基板,2〜 45%的B 2 O 3和/或Al 2 O 3和0〜40%的R'2O,其中R'为选自Li,Na和K中的至少一种),其中SiO 2,B 2 O 3,Al 2 O 3和 R'2O为90摩尔%以上,磁性信息记录媒体包含形成在玻璃基板上的磁记录层。
摘要:
A substrate for an information recording medium, which has high heat resistance and high acid resistance and is formed of a glass having a glass transition temperature (Tg) of 600° C. or higher and having an etching rate of 0.1 μm/minute or less with regard to a hydrosilicofluoric acid aqueous solution that is maintained at a temperature of 45° C. and has a hydrosilicofluoric acid concentration of 1.72% by weight, and an information recording medium having an information recording layer formed on the above substrate.
摘要:
A low-dispersion optical glass suitable for producing a quality preform from a molten glass and suitable for precision press-molding, which is a fluorophosphate glass containing, as essential cationic components, P5+, Al3+, at least two members selected from Mg2+, Ca2+, Sr2+ and Ba2+ as divalent cationic components (R2+) and Li+ and containing, by cationic %, 10 to 45% of P5+, 5 to 30% of Al3+, 0 to 20% of Mg2+, 0 to 25% of Ca2+, 0 to 30% of Sr2+, 0 to 33% of Ba2+, 1 to 30% of Li+, 0 to 10% of Na+, 0 to 10% of K+, 0 to 5% of Y3+, and 0 to 15% of B3+, the molar ratio of the content of F− to the total content of F− and O2−, F−/(F−+O2−) being 0.25 to 0.85, the optical glass having a refractive index (Nd) of 1.40 to 1.58 and an Abbe's number (νd) of 67 to 90.
摘要:
A glass for use in chemical reinforcement for use in a substrate of an information recording medium, having a composition comprising, denoted as mol %: SiO247 to 70% Al2O31 to 10% (where the total of SiO2 and Al2O3 is 57 to 80%) CaO2 to 25% BaO1 to 15% Na2O1 to 10% K2O0 to 15% (where the total of Na2O and K2O is 3 to 16%) ZrO21 to 12% MgO0 to 10% SrO0 to 15% (where the ratio of the content of CaO to the total of MgO, CaO, SrO, and BaO is greater than or equal to 0.5) ZnO0 to 10% (where the total of MgO, CaO, SrO, BaO, and ZnO is 3 to 30%) TiO20 to 10% and the total content of the above-stated components is greater than or equal to 95%. A glass for use in chemical reinforcement for use in the substrate of an information recording medium employed in a perpendicular magnetic recording system, in which the glass exhibits the glass transition temperature is greater than or equal to 600° C. A substrate for use in an information recording medium consisting of the above glass and being chemically reinforced. A substrate for an information recording medium consisting of a chemically reinforced glass having a glass transition temperature of greater than or equal to 600° C. and exhibiting a bending strength following heating for two hours at 570° C. of greater than or equal to 15 kgf/mm2. An information recording medium comprising an information recording layer on the above substrate for an information recording medium. The present invention provides glass having both high thermal resistance and high strength, a substrate for use in information recording media comprised of this glass, and an information recording medium employing such a substrate.
摘要:
Disclosed are a glass substrate for an information recording medium, having excellent scratch resistance and a light weight and having high fracture toughness, the glass substrate having a fragility index value, measured in water, of 12 μm−1/2 or less or having a fragility index value, measured in an atmosphere having a dew point of −5° C. or lower, of 7 μm−1/2 or less, or the glass substrate comprising, by mol %, 40 to 75% of SiO2, 2 to 45% of B2O3 and/or Al2O3 and 0 to 40% of R′2O in which R′ is at least one member selected from the group consisting of Li, Na and K), wherein the total content of SiO2, B2O3, Al2O3 and R′2O is at least 90 mol %, and a magnetic information recording medium comprising a magnetic recording layer formed on the glass substrate.
摘要翻译:公开了一种用于信息记录介质的玻璃基板,具有优异的耐擦伤性和重量轻并且具有高断裂韧性,玻璃基板在水中测得的脆性指数值为12μm-1/2或更小,或具有 在露点为-5℃以下的气氛中测定的7μm-1/2以下的脆性指数值,或摩尔%为40〜75%的SiO 2的玻璃基板,2〜 45%的B 2 O 3和/或Al 2 O 3和0〜40%的R'2O,其中R'为选自Li,Na和K中的至少一种),其中SiO 2,B 2 O 3,Al 2 O 3和 R'2O为90摩尔%以上,磁性信息记录媒体包含形成在玻璃基板上的磁记录层。
摘要:
A low-dispersion optical glass suitable for producing a quality preform from a molten glass and suitable for precision press-molding, which is a fluorophosphate glass containing, as essential cationic components, P5+, Al3+, at least two members selected from Mg2+, Ca2+, Sr2+ and Ba2+ as divalent cationic components (R2+) and Li+ and containing, by cationic %, 10 to 45% of P5+, 5 to 30% of Al3+, 0 to 20% of Mg2+, 0 to 25% of Ca2+, 0 to 30% of Sr2+, 0 to 33% of Ba2+, 1 to 30% of Li+, 0 to 10% of Na+, 0 to 10% of K+, 0 to 5% of Y3+, and 0 to 15% of B3+, the molar ratio of the content of F− to the total content of F− and O2−, F−/(F−+O2−), being 0.25 to 0.85, the optical glass having a refractive index (Nd) of 1.40 to 1.58 and an Abbe's number (νd) of 67 to 90.
摘要:
A process for producing a precision press-molding preform having a predetermined weight from a molten glass, wherein the molten glass is shaped into a glass gob and the above glass gob is etched to remove a surface layer of the glass gob to produce the precision press-molding preform formed of an optical glass having said weight, and further wherein said surface layer has a thickness of 0.5 μm or more.
摘要:
According to one aspect of the present invention, provided is glass for use in substrate for information recording medium, which comprises, denoted as molar percentages, a total of 70 to 85 percent of SiO2 and Al2O3, where SiO2 content is equal to or greater than 50 percent and Al2O3 content is equal to or greater than 3 percent; a total of equal to or greater than 10 percent of Li2O, Na2O and K2O; a total of 1 to 6 percent of CaO and MgO, where CaO content is greater than MgO content; a total of greater than 0 percent but equal to or lower than 4 percent of ZrO2, HfO2, Nb2O5, Ta2O5, La2O3Y2O3 and TiO2; with the molar ratio of the total content of Li2O, Na2O and K2O to the total content of SiO2, Al2O3, ZrO2, HfO2, Nb2O5, Ta2O5, La2O3, Y2O3 and TiO2((Li2O+Na2O+K2O)/(SiO2+Al2O3+ZrO2+HfO2+Nb2O5+Ta2O5+La2O3+Y2O3+TiO2)) being equal to or less than 0.28. Further provided are the substrate for information recording medium, information recording medium and their manufacturing methods according to the present invention.
摘要翻译:根据本发明的一个方面,提供了一种用于信息记录介质的基板的玻璃,其包括以摩尔百分数表示的总和为70〜85%的SiO 2和Al 2 O 3,其中SiO 2含量等于或大于 50%,Al2O3含量等于或大于3%; 总计等于或大于10%的Li2O,Na2O和K2O; CaO和MgO的总量为1〜6%,其中CaO含量大于MgO含量; 总共大于0%但等于或低于ZrO2,HfO2,Nb2O5,Ta2O5,La2O3Y2O3和TiO2的4%; 其中Li2O,Na2O和K2O的总含量与SiO2,Al2O3,ZrO2,HfO2,Nb2O5,Ta2O5,La2O3,Y2O3和TiO2((Li2O + Na2O + K2O)/(SiO2 + Al2O3 + ZrO 2 + HfO 2 + Nb 2 O 5 + Ta 2 O 5 + La 2 O 3 + Y 2 O 3 + TiO 2))等于或小于0.28。 还提供了根据本发明的用于信息记录介质的基板,信息记录介质及其制造方法。
摘要:
Provided is an optically uniform and high-quality optical glass that is free from the occurrence of striae when a precision press-molding preform is produced therefrom, and that is a fluorine-containing glass having a refractive index nd(1) wherein the refractive index nd(1) and a refractive index nd(2) are substantially equivalent to each other, said refractive index nd(2) being a refractive index of the fluorine-containing glass after the fluorine-containing glass is re-melted in a nitrogen atmosphere at 900° C. for 1 hour, cooled to its glass transition temperature and then cooled to 25° C. at a temperature decrease rate of 30° C./hour.