| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To reduce heat conductivity of a vacuum heat insulating material using glass fiber for a core material. <P>SOLUTION: This vacuum heat insulating material 1 is composed of the core material 2 and a skin material 6. Glass for constituting the glass fiber used for the core material 2 contains SiO<SB>2</SB>, Na<SB>2</SB>O, K<SB>2</SB>O and Al<SB>2</SB>O<SB>3</SB>, and the SiO<SB>2</SB>ratio of a glass composition is set to 45 to 70 wt.%. Since the total of the Na<SB>2</SB>O ratio and the K<SB>2</SB>O ratio of the glass composition is more than the total of the Al<SB>2</SB>O<SB>3</SB>ratio and the MgO ratio, when using glass of this composition, manufacturing cost of the glass fiber can be reduced, and manufacturing cost of the vacuum heat insulating material 1 can be reduced. The vacuum heat insulating material 1 having low heat conductivity can be provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
