Vacuum insulating material and device using the same

A vacuum heat insulator comprising:

• inorganic fibers, said inorganic fibers including SiO2 as a main component, Al2O3, CaO, and MgO, a fiber diameter of said inorganic fibers having a peak value of distribution of 1 μm or smaller and 0.1 μm or larger;
• an enveloping member;
• and
• an absorbent,
• wherein a bulk density of said inorganic fibers is 15 Kg/m3 or more and 100 Kg/m3 or less, and a bulk density of said inorganic fibers after an compression is 100 Kg/m3 or more and 300 Kg/m3 or less.

A hot/cold preserving apparatus using vacuum heat insulator for heat insulation, said vacuum heat insulator comprising:

• a laminated core comprising a plurality of sheet-formed inorganic fibers;
• an enveloping member;
• and
• an absorbent,
• wherein said inorganic fibers include 50-65 wt % of SiO2, 10-20 wt % of Al2O3, 10-20 wt % of CaO, and 1-4 wt % of MgO, a fiber diameter of said inorganic fibers is 1 μm or larger and 5 μm or smaller, and a bulk density is 100 Kg/m3 or more and 300 Kg/m3 or less.

An electric apparatus including a vacuum heat insulator, said vacuum heat insulator comprising:

• a core comprising inorganic fibers including a main component of SiO2 and having a peak value of distribution in fiber diameter of 1 μm or smaller and 0.1 μm or larger, a bulk density of said inorganic fibers being 15 Kg/m3 or more and 100 Kg/m3 or less, and a bulk density of said inorganic fibers after an compression being 100 Kg/m3 or more and 300 Kg/m3 or less, and said core not containing a binding material for fixing fiber material;
• an absorbent;
• and
• an enveloping member.