摘要:
A glass substrate of the present invention for magnetic recording media having high heat resistance and easy chemical strengthening ability at once has not been obtained, which is a glass composition essentially comprising 60 to 70 wt % SiO2, 5 to 20 wt % Al2O3, 0 to 1 wt % Li2O, 3 to 18 wt % Na2O, 0 to 9 wt % K2O, 0 to 10 wt % MgO, 1 to 15 wt % CaO, 0 to 4.5 wt % SrO, 0 to 1 wt % BaO, 0 to 1 wt % TiO2 and 0 to 1 wt % ZrO2, wherein the sum of Li2O, Na2O and K2O is from 5 to 25 wt %, and the sum of MgO, CaO, SrO and BaO is from 5 to 20 wt %.
摘要:
A glass substrate for an information recording medium has an acid resistance represented by an etching rate of at most 45 nm/min. upon contact with a hydrofluoric acid having a temperature of 50° C. and a concentration of 0.1 weight %. The glass substrate has a recording surface having an average surface roughness Ra smaller than 0.3 nm.
摘要:
A glass composition is disclosed which has a high modulus of elasticity (Young's modulus) and a high rigidity (modulus of elasticity/specific gravity) and is capable of being effectively inhibited from bending or vibrating. Also disclosed is process for producing the glass composition. The glass composition comprises, in terms of mol %, 40 to 65% SiO2, 5 to 25% Al2O3, 2 to 20% Li2O, 0 to 9% Na2O, 0 to 10% TiO2, 0 to 10% ZrO2, 0 to 25% MgO, 0 to 25% CaO, and 0 to 10% SrO, provided that the content of RO (RO=MgO+CaO+SrO) is from 2 to 40% and the sum of (Li2O)/2 and Na2O is from 1 to 10 mol %, said glass composition further containing, as clarifiers, from 0.01 to 5 mol % SnO2 and up to 0.1 mol % sulfur (S) in terms of the amount of SO3.
摘要:
A glass composition is disclosed which has a high modulus of elasticity (Young's modulus) and a high rigidity (modulus of elasticity/specific gravity) and is capable of being effectively inhibited from bending or vibrating. Also disclosed is a substrate for information recording media, which comprises the glass composition. The glass composition comprises the following components in terms of mol %: 50 to 64% SiO2, 6 to 18% Al2O3, 7 to 15% Li2O, 3 to 12% Na2O, 0 to 2% K2O, 0 to 10% TiO2, 0 to 4% ZrO2, 0 to 6% MgO, 0 to 9% CaO, and 0 to 6% SrO, provided that the content of RO (RO=MgO+CaO+SrO) is from 2 to 15%.
摘要:
A glass substrate of the present invention for magnetic recording media having high heat resistance and easy chemical strengthening ability at once has not been obtained, which is a glass composition essentially comprising 60 to 70 wt % SiO2, 5 to 20 wt % Al2O3, 0 to 1 wt % Li2O, 3 to 18 wt % Na2O, 0 to 9 wt % K2O, 0 to 10 wt % MgO, 1 to 15 wt % CaO, 0 to 4.5 wt % SrO, 0 to 1 wt % BaO, 0 to 1 wt % TiO2 and 0 to 1 wt % ZrO2, wherein the sum of Li2O, Na2O and K2O is from 5 to 25 wt %, and the sum of MgO, CaO, SrO and BaO is from 5 to 20 wt %.
摘要翻译:本发明的用于磁记录介质的具有高耐热性并且容易化学强化能力的本发明的玻璃基板尚未得到,它是基本上包含60至70重量%的SiO 2,5 至20重量%的Al 2 O 3 3,0至1重量%的Li 2 O 3,3至18重量%的Na 2, ,0〜9重量%的K 2 O,0〜10重量%的MgO,1〜15重量%的CaO,0〜4.5重量%的SrO,0〜1重量%的BaO,0 至1重量%的TiO 2和0至1重量%的ZrO 2,其中Li 2 O 2,Na 2, O 2和K 2 O 5为5〜25重量%,MgO,CaO,SrO和BaO的总和为5〜20重量%。
摘要:
A glass substrate of the present invention for magnetic recording media having high heat resistance and easy chemical strengthening ability at once has not been obtained, which is a glass composition essentially comprising 60 to 70 wt % SiO2, 5 to 20 wt % Al2O3, 0 to 1 wt % Li2O, 3 to 18 wt % Na2O, 0 to 9 wt % K2O, 0 to 10 wt % MgO, 1 to 15 wt % CaO, 0 to 4.5 wt % SrO, 0 to 1 wt % BaO, 0 to 1 wt % TiO2 and 0 to 1 wt % ZrO2, wherein the sum of Li2O, Na2O and K2O is from 5 to 25 wt %, and the sum of MgO, CaO, SrO and BaO is from 5 to 20 wt %.
摘要翻译:本发明的用于磁记录介质的具有高耐热性并且容易化学强化能力的本发明的玻璃基板尚未得到,它是基本上包含60至70重量%的SiO 2,5 至20重量%的Al 2 O 3 3,0至1重量%的Li 2 O 3,3至18重量%的Na 2, ,0〜9重量%的K 2 O,0〜10重量%的MgO,1〜15重量%的CaO,0〜4.5重量%的SrO,0〜1重量%的BaO,0 至1重量%的TiO 2和0至1重量%的ZrO 2,其中Li 2 O 2,Na 2, O 2和K 2 O 5为5〜25重量%,MgO,CaO,SrO和BaO的总和为5〜20重量%。
摘要:
A glass composition is disclosed which has a high modulus of elasticity (Young's modulus) and a high rigidity (modulus of elasticity/specific gravity) and is capable of being effectively inhibited from bending or vibrating. Also disclosed is a substrate for information recording media, which comprises the glass composition. The glass composition comprises the following components in terms of mol %: 40 to 60% SiO2, 8 to 25% Al2O3, 2 to 20% Li2O, 0 to 5% Na2O; provided that the content of R2O (R2O=Li2O+Na2O) is from 2 to 20%, 0 to 10% TiO2, 0 to 10% ZrO2, 5 to 25% MgO, 0 to 25% CaO and 0 to 6% SrO, provided that the content of RO (RO=MgO+CaO+SrO) is from more than 15 to 40%.
摘要:
A glass composition having a high Young's modulus and a low density is disclosed which can be mass-produced by a continuous process and easily made to have high surface smoothness. Also disclosed are a substrate including the glass composition and reduced in bending and resonance even upon high-speed rotation, a recording medium usable at a lower flying height, and an information recording device having a higher recording capacity and a shorter access time. The glass composition includes, in terms of mol %, 40 to 55% silicon dioxide (SiO2), 0.5 to 6% aluminum oxide (Al2O3), 2 to 20% lithium oxide (Li2O), 0 to 10% sodium monoxide ((Na2O), 2 to 30% R2O (R2O=Li2O+Na2O), 5 to 25% magnesium oxide (MgO), 0 to 25% calcium oxide (CaO), 0 to 10% strontium oxide (SrO), 10 to 40% RO (RO=MgO+CaO+SrO), 0 to 10% titanium dioxide (TiO2), and 0 to 5% zirconium oxide (ZrO2).
摘要:
A glass composition is disclosed which has a high modulus elasticity (Young's modulus) and a high rigidity (modulus of elasticity/specific gravity) and is capable of being effectively inhibited from bending or vibrating. Also disclosed is a process for producing the glass composition. The glass composition comprises, in terms of mol %, 40 to 65% SiO2, 5 to 25% Al2O3, 2 to 20% Li2O, 0 to 9% Na2O, 0 to 10% TiO2, 0 to 10% ZrO2, 0 to 25% MgO, 0 to 25% CaO, and 0 to 10% SrO, provided that the content of RO (RO=MgO+CaO+SrO) is from 2 to 40% and the sum of (Li2O)/2 and Na2O is from 1 to 10 mol %, said glass composition further containing, as clarifiers, from 0.01 to 5 mol % SnO2 and up to 0.1 mol % sulfur (S) in terms of the amount of SO3.