Heat regenerating material, regenerator, refrigerator, superconducting magnet, nuclear magnetic resonance imaging apparatus, nuclear magnetic resonance apparatus, cryopump, and magnetic field application type single crystal pulling apparatus
A heat regenerating material particle according to an embodiment includes a plurality of heat regenerating substance particles having a maximum volume specific heat value of 0.3 J/cm 3 ·K or more at a temperature of 20 K or lower, and a binder bonding the heat regenerating substance particles, the binder containing water insoluble resin. The heat regenerating material particle has a particle diameter of 500 μm or less.
1. A regenerator comprising: a plurality of heat regenerating materials, which comprise
a plurality of heat regenerating substance particles having a maximum volume specific heat value of 0.3 J/cm 3 ·K or more at a temperature of 20 K or lower; and
a binder bonding the heat regenerating substance particles, the binder containing water insoluble resin, wherein
the water insoluble resin is a polyvinyl butyral resin,
the heat regenerating material has a particle diameter of 500 μm or less, and the binder has an occupancy ratio of more than 5% by volume in the heat regenerating material.
2. A refrigerator comprising the regenerator according to claim 1 .
3. A superconducting magnet comprising the refrigerator according to claim 2 .
4. A nuclear magnetic resonance imaging apparatus comprising the refrigerator according to claim 2 .
5. A nuclear magnetic resonance apparatus comprising the refrigerator according to claim 2 .
6. A cryopump comprising the refrigerator according to claim 2 .
7. A magnetic field application type single crystal pulling apparatus comprising the refrigerator according to claim 2 .